// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2007 Oracle. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ctree.h" #include "disk-io.h" #include "transaction.h" #include "btrfs_inode.h" #include "print-tree.h" #include "ordered-data.h" #include "xattr.h" #include "tree-log.h" #include "volumes.h" #include "compression.h" #include "locking.h" #include "free-space-cache.h" #include "inode-map.h" #include "backref.h" #include "props.h" #include "qgroup.h" #include "dedupe.h" struct btrfs_iget_args { struct btrfs_key *location; struct btrfs_root *root; }; struct btrfs_dio_data { u64 reserve; u64 unsubmitted_oe_range_start; u64 unsubmitted_oe_range_end; int overwrite; }; static const struct inode_operations btrfs_dir_inode_operations; static const struct inode_operations btrfs_symlink_inode_operations; static const struct inode_operations btrfs_dir_ro_inode_operations; static const struct inode_operations btrfs_special_inode_operations; static const struct inode_operations btrfs_file_inode_operations; static const struct address_space_operations btrfs_aops; static const struct file_operations btrfs_dir_file_operations; static const struct extent_io_ops btrfs_extent_io_ops; static struct kmem_cache *btrfs_inode_cachep; struct kmem_cache *btrfs_trans_handle_cachep; struct kmem_cache *btrfs_path_cachep; struct kmem_cache *btrfs_free_space_cachep; #define S_SHIFT 12 static const unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = { [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE, [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR, [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV, [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV, [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO, [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK, [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK, }; static int btrfs_setsize(struct inode *inode, struct iattr *attr); static int btrfs_truncate(struct inode *inode, bool skip_writeback); static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent); static noinline int cow_file_range(struct inode *inode, struct page *locked_page, u64 start, u64 end, u64 delalloc_end, int *page_started, unsigned long *nr_written, int unlock, struct btrfs_dedupe_hash *hash); static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len, u64 orig_start, u64 block_start, u64 block_len, u64 orig_block_len, u64 ram_bytes, int compress_type, int type); static void __endio_write_update_ordered(struct inode *inode, const u64 offset, const u64 bytes, const bool uptodate); /* * Cleanup all submitted ordered extents in specified range to handle errors * from the btrfs_run_delalloc_range() callback. * * NOTE: caller must ensure that when an error happens, it can not call * extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING * and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata * to be released, which we want to happen only when finishing the ordered * extent (btrfs_finish_ordered_io()). */ static inline void btrfs_cleanup_ordered_extents(struct inode *inode, struct page *locked_page, u64 offset, u64 bytes) { unsigned long index = offset >> PAGE_SHIFT; unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT; u64 page_start = page_offset(locked_page); u64 page_end = page_start + PAGE_SIZE - 1; struct page *page; while (index <= end_index) { page = find_get_page(inode->i_mapping, index); index++; if (!page) continue; ClearPagePrivate2(page); put_page(page); } /* * In case this page belongs to the delalloc range being instantiated * then skip it, since the first page of a range is going to be * properly cleaned up by the caller of run_delalloc_range */ if (page_start >= offset && page_end <= (offset + bytes - 1)) { offset += PAGE_SIZE; bytes -= PAGE_SIZE; } return __endio_write_update_ordered(inode, offset, bytes, false); } static int btrfs_dirty_inode(struct inode *inode); #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS void btrfs_test_inode_set_ops(struct inode *inode) { BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; } #endif static int btrfs_init_inode_security(struct btrfs_trans_handle *trans, struct inode *inode, struct inode *dir, const struct qstr *qstr) { int err; err = btrfs_init_acl(trans, inode, dir); if (!err) err = btrfs_xattr_security_init(trans, inode, dir, qstr); return err; } /* * this does all the hard work for inserting an inline extent into * the btree. The caller should have done a btrfs_drop_extents so that * no overlapping inline items exist in the btree */ static int insert_inline_extent(struct btrfs_trans_handle *trans, struct btrfs_path *path, int extent_inserted, struct btrfs_root *root, struct inode *inode, u64 start, size_t size, size_t compressed_size, int compress_type, struct page **compressed_pages) { struct extent_buffer *leaf; struct page *page = NULL; char *kaddr; unsigned long ptr; struct btrfs_file_extent_item *ei; int ret; size_t cur_size = size; unsigned long offset; if (compressed_size && compressed_pages) cur_size = compressed_size; inode_add_bytes(inode, size); if (!extent_inserted) { struct btrfs_key key; size_t datasize; key.objectid = btrfs_ino(BTRFS_I(inode)); key.offset = start; key.type = BTRFS_EXTENT_DATA_KEY; datasize = btrfs_file_extent_calc_inline_size(cur_size); path->leave_spinning = 1; ret = btrfs_insert_empty_item(trans, root, path, &key, datasize); if (ret) goto fail; } leaf = path->nodes[0]; ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, ei, trans->transid); btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); btrfs_set_file_extent_encryption(leaf, ei, 0); btrfs_set_file_extent_other_encoding(leaf, ei, 0); btrfs_set_file_extent_ram_bytes(leaf, ei, size); ptr = btrfs_file_extent_inline_start(ei); if (compress_type != BTRFS_COMPRESS_NONE) { struct page *cpage; int i = 0; while (compressed_size > 0) { cpage = compressed_pages[i]; cur_size = min_t(unsigned long, compressed_size, PAGE_SIZE); kaddr = kmap_atomic(cpage); write_extent_buffer(leaf, kaddr, ptr, cur_size); kunmap_atomic(kaddr); i++; ptr += cur_size; compressed_size -= cur_size; } btrfs_set_file_extent_compression(leaf, ei, compress_type); } else { page = find_get_page(inode->i_mapping, start >> PAGE_SHIFT); btrfs_set_file_extent_compression(leaf, ei, 0); kaddr = kmap_atomic(page); offset = offset_in_page(start); write_extent_buffer(leaf, kaddr + offset, ptr, size); kunmap_atomic(kaddr); put_page(page); } btrfs_mark_buffer_dirty(leaf); btrfs_release_path(path); /* * we're an inline extent, so nobody can * extend the file past i_size without locking * a page we already have locked. * * We must do any isize and inode updates * before we unlock the pages. Otherwise we * could end up racing with unlink. */ BTRFS_I(inode)->disk_i_size = inode->i_size; ret = btrfs_update_inode(trans, root, inode); fail: return ret; } /* * conditionally insert an inline extent into the file. This * does the checks required to make sure the data is small enough * to fit as an inline extent. */ static noinline int cow_file_range_inline(struct inode *inode, u64 start, u64 end, size_t compressed_size, int compress_type, struct page **compressed_pages) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_trans_handle *trans; u64 isize = i_size_read(inode); u64 actual_end = min(end + 1, isize); u64 inline_len = actual_end - start; u64 aligned_end = ALIGN(end, fs_info->sectorsize); u64 data_len = inline_len; int ret; struct btrfs_path *path; int extent_inserted = 0; u32 extent_item_size; if (compressed_size) data_len = compressed_size; if (start > 0 || actual_end > fs_info->sectorsize || data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) || (!compressed_size && (actual_end & (fs_info->sectorsize - 1)) == 0) || end + 1 < isize || data_len > fs_info->max_inline) { return 1; } path = btrfs_alloc_path(); if (!path) return -ENOMEM; trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } trans->block_rsv = &BTRFS_I(inode)->block_rsv; if (compressed_size && compressed_pages) extent_item_size = btrfs_file_extent_calc_inline_size( compressed_size); else extent_item_size = btrfs_file_extent_calc_inline_size( inline_len); ret = __btrfs_drop_extents(trans, root, inode, path, start, aligned_end, NULL, 1, 1, extent_item_size, &extent_inserted); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } if (isize > actual_end) inline_len = min_t(u64, isize, actual_end); ret = insert_inline_extent(trans, path, extent_inserted, root, inode, start, inline_len, compressed_size, compress_type, compressed_pages); if (ret && ret != -ENOSPC) { btrfs_abort_transaction(trans, ret); goto out; } else if (ret == -ENOSPC) { ret = 1; goto out; } set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); btrfs_drop_extent_cache(BTRFS_I(inode), start, aligned_end - 1, 0); out: /* * Don't forget to free the reserved space, as for inlined extent * it won't count as data extent, free them directly here. * And at reserve time, it's always aligned to page size, so * just free one page here. */ btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE); btrfs_free_path(path); btrfs_end_transaction(trans); return ret; } struct async_extent { u64 start; u64 ram_size; u64 compressed_size; struct page **pages; unsigned long nr_pages; int compress_type; struct list_head list; }; struct async_cow { struct inode *inode; struct btrfs_fs_info *fs_info; struct page *locked_page; u64 start; u64 end; unsigned int write_flags; struct list_head extents; struct btrfs_work work; }; static noinline int add_async_extent(struct async_cow *cow, u64 start, u64 ram_size, u64 compressed_size, struct page **pages, unsigned long nr_pages, int compress_type) { struct async_extent *async_extent; async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); BUG_ON(!async_extent); /* -ENOMEM */ async_extent->start = start; async_extent->ram_size = ram_size; async_extent->compressed_size = compressed_size; async_extent->pages = pages; async_extent->nr_pages = nr_pages; async_extent->compress_type = compress_type; list_add_tail(&async_extent->list, &cow->extents); return 0; } static inline int inode_need_compress(struct inode *inode, u64 start, u64 end) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); /* force compress */ if (btrfs_test_opt(fs_info, FORCE_COMPRESS)) return 1; /* defrag ioctl */ if (BTRFS_I(inode)->defrag_compress) return 1; /* bad compression ratios */ if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) return 0; if (btrfs_test_opt(fs_info, COMPRESS) || BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS || BTRFS_I(inode)->prop_compress) return btrfs_compress_heuristic(inode, start, end); return 0; } static inline void inode_should_defrag(struct btrfs_inode *inode, u64 start, u64 end, u64 num_bytes, u64 small_write) { /* If this is a small write inside eof, kick off a defrag */ if (num_bytes < small_write && (start > 0 || end + 1 < inode->disk_i_size)) btrfs_add_inode_defrag(NULL, inode); } /* * we create compressed extents in two phases. The first * phase compresses a range of pages that have already been * locked (both pages and state bits are locked). * * This is done inside an ordered work queue, and the compression * is spread across many cpus. The actual IO submission is step * two, and the ordered work queue takes care of making sure that * happens in the same order things were put onto the queue by * writepages and friends. * * If this code finds it can't get good compression, it puts an * entry onto the work queue to write the uncompressed bytes. This * makes sure that both compressed inodes and uncompressed inodes * are written in the same order that the flusher thread sent them * down. */ static noinline void compress_file_range(struct inode *inode, struct page *locked_page, u64 start, u64 end, struct async_cow *async_cow, int *num_added) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); u64 blocksize = fs_info->sectorsize; u64 actual_end; u64 isize = i_size_read(inode); int ret = 0; struct page **pages = NULL; unsigned long nr_pages; unsigned long total_compressed = 0; unsigned long total_in = 0; int i; int will_compress; int compress_type = fs_info->compress_type; int redirty = 0; inode_should_defrag(BTRFS_I(inode), start, end, end - start + 1, SZ_16K); actual_end = min_t(u64, isize, end + 1); again: will_compress = 0; nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1; BUILD_BUG_ON((BTRFS_MAX_COMPRESSED % PAGE_SIZE) != 0); nr_pages = min_t(unsigned long, nr_pages, BTRFS_MAX_COMPRESSED / PAGE_SIZE); /* * we don't want to send crud past the end of i_size through * compression, that's just a waste of CPU time. So, if the * end of the file is before the start of our current * requested range of bytes, we bail out to the uncompressed * cleanup code that can deal with all of this. * * It isn't really the fastest way to fix things, but this is a * very uncommon corner. */ if (actual_end <= start) goto cleanup_and_bail_uncompressed; total_compressed = actual_end - start; /* * skip compression for a small file range(<=blocksize) that * isn't an inline extent, since it doesn't save disk space at all. */ if (total_compressed <= blocksize && (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) goto cleanup_and_bail_uncompressed; total_compressed = min_t(unsigned long, total_compressed, BTRFS_MAX_UNCOMPRESSED); total_in = 0; ret = 0; /* * we do compression for mount -o compress and when the * inode has not been flagged as nocompress. This flag can * change at any time if we discover bad compression ratios. */ if (inode_need_compress(inode, start, end)) { WARN_ON(pages); pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); if (!pages) { /* just bail out to the uncompressed code */ nr_pages = 0; goto cont; } if (BTRFS_I(inode)->defrag_compress) compress_type = BTRFS_I(inode)->defrag_compress; else if (BTRFS_I(inode)->prop_compress) compress_type = BTRFS_I(inode)->prop_compress; /* * we need to call clear_page_dirty_for_io on each * page in the range. Otherwise applications with the file * mmap'd can wander in and change the page contents while * we are compressing them. * * If the compression fails for any reason, we set the pages * dirty again later on. * * Note that the remaining part is redirtied, the start pointer * has moved, the end is the original one. */ if (!redirty) { extent_range_clear_dirty_for_io(inode, start, end); redirty = 1; } /* Compression level is applied here and only here */ ret = btrfs_compress_pages( compress_type | (fs_info->compress_level << 4), inode->i_mapping, start, pages, &nr_pages, &total_in, &total_compressed); if (!ret) { unsigned long offset = offset_in_page(total_compressed); struct page *page = pages[nr_pages - 1]; char *kaddr; /* zero the tail end of the last page, we might be * sending it down to disk */ if (offset) { kaddr = kmap_atomic(page); memset(kaddr + offset, 0, PAGE_SIZE - offset); kunmap_atomic(kaddr); } will_compress = 1; } } cont: if (start == 0) { /* lets try to make an inline extent */ if (ret || total_in < actual_end) { /* we didn't compress the entire range, try * to make an uncompressed inline extent. */ ret = cow_file_range_inline(inode, start, end, 0, BTRFS_COMPRESS_NONE, NULL); } else { /* try making a compressed inline extent */ ret = cow_file_range_inline(inode, start, end, total_compressed, compress_type, pages); } if (ret <= 0) { unsigned long clear_flags = EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING; unsigned long page_error_op; page_error_op = ret < 0 ? PAGE_SET_ERROR : 0; /* * inline extent creation worked or returned error, * we don't need to create any more async work items. * Unlock and free up our temp pages. * * We use DO_ACCOUNTING here because we need the * delalloc_release_metadata to be done _after_ we drop * our outstanding extent for clearing delalloc for this * range. */ extent_clear_unlock_delalloc(inode, start, end, end, NULL, clear_flags, PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | page_error_op | PAGE_END_WRITEBACK); goto free_pages_out; } } if (will_compress) { /* * we aren't doing an inline extent round the compressed size * up to a block size boundary so the allocator does sane * things */ total_compressed = ALIGN(total_compressed, blocksize); /* * one last check to make sure the compression is really a * win, compare the page count read with the blocks on disk, * compression must free at least one sector size */ total_in = ALIGN(total_in, PAGE_SIZE); if (total_compressed + blocksize <= total_in) { *num_added += 1; /* * The async work queues will take care of doing actual * allocation on disk for these compressed pages, and * will submit them to the elevator. */ add_async_extent(async_cow, start, total_in, total_compressed, pages, nr_pages, compress_type); if (start + total_in < end) { start += total_in; pages = NULL; cond_resched(); goto again; } return; } } if (pages) { /* * the compression code ran but failed to make things smaller, * free any pages it allocated and our page pointer array */ for (i = 0; i < nr_pages; i++) { WARN_ON(pages[i]->mapping); put_page(pages[i]); } kfree(pages); pages = NULL; total_compressed = 0; nr_pages = 0; /* flag the file so we don't compress in the future */ if (!btrfs_test_opt(fs_info, FORCE_COMPRESS) && !(BTRFS_I(inode)->prop_compress)) { BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; } } cleanup_and_bail_uncompressed: /* * No compression, but we still need to write the pages in the file * we've been given so far. redirty the locked page if it corresponds * to our extent and set things up for the async work queue to run * cow_file_range to do the normal delalloc dance. */ if (page_offset(locked_page) >= start && page_offset(locked_page) <= end) __set_page_dirty_nobuffers(locked_page); /* unlocked later on in the async handlers */ if (redirty) extent_range_redirty_for_io(inode, start, end); add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0, BTRFS_COMPRESS_NONE); *num_added += 1; return; free_pages_out: for (i = 0; i < nr_pages; i++) { WARN_ON(pages[i]->mapping); put_page(pages[i]); } kfree(pages); } static void free_async_extent_pages(struct async_extent *async_extent) { int i; if (!async_extent->pages) return; for (i = 0; i < async_extent->nr_pages; i++) { WARN_ON(async_extent->pages[i]->mapping); put_page(async_extent->pages[i]); } kfree(async_extent->pages); async_extent->nr_pages = 0; async_extent->pages = NULL; } /* * phase two of compressed writeback. This is the ordered portion * of the code, which only gets called in the order the work was * queued. We walk all the async extents created by compress_file_range * and send them down to the disk. */ static noinline void submit_compressed_extents(struct inode *inode, struct async_cow *async_cow) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct async_extent *async_extent; u64 alloc_hint = 0; struct btrfs_key ins; struct extent_map *em; struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_io_tree *io_tree; int ret = 0; again: while (!list_empty(&async_cow->extents)) { async_extent = list_entry(async_cow->extents.next, struct async_extent, list); list_del(&async_extent->list); io_tree = &BTRFS_I(inode)->io_tree; retry: /* did the compression code fall back to uncompressed IO? */ if (!async_extent->pages) { int page_started = 0; unsigned long nr_written = 0; lock_extent(io_tree, async_extent->start, async_extent->start + async_extent->ram_size - 1); /* allocate blocks */ ret = cow_file_range(inode, async_cow->locked_page, async_extent->start, async_extent->start + async_extent->ram_size - 1, async_extent->start + async_extent->ram_size - 1, &page_started, &nr_written, 0, NULL); /* JDM XXX */ /* * if page_started, cow_file_range inserted an * inline extent and took care of all the unlocking * and IO for us. Otherwise, we need to submit * all those pages down to the drive. */ if (!page_started && !ret) extent_write_locked_range(inode, async_extent->start, async_extent->start + async_extent->ram_size - 1, WB_SYNC_ALL); else if (ret) unlock_page(async_cow->locked_page); kfree(async_extent); cond_resched(); continue; } lock_extent(io_tree, async_extent->start, async_extent->start + async_extent->ram_size - 1); ret = btrfs_reserve_extent(root, async_extent->ram_size, async_extent->compressed_size, async_extent->compressed_size, 0, alloc_hint, &ins, 1, 1); if (ret) { free_async_extent_pages(async_extent); if (ret == -ENOSPC) { unlock_extent(io_tree, async_extent->start, async_extent->start + async_extent->ram_size - 1); /* * we need to redirty the pages if we decide to * fallback to uncompressed IO, otherwise we * will not submit these pages down to lower * layers. */ extent_range_redirty_for_io(inode, async_extent->start, async_extent->start + async_extent->ram_size - 1); goto retry; } goto out_free; } /* * here we're doing allocation and writeback of the * compressed pages */ em = create_io_em(inode, async_extent->start, async_extent->ram_size, /* len */ async_extent->start, /* orig_start */ ins.objectid, /* block_start */ ins.offset, /* block_len */ ins.offset, /* orig_block_len */ async_extent->ram_size, /* ram_bytes */ async_extent->compress_type, BTRFS_ORDERED_COMPRESSED); if (IS_ERR(em)) /* ret value is not necessary due to void function */ goto out_free_reserve; free_extent_map(em); ret = btrfs_add_ordered_extent_compress(inode, async_extent->start, ins.objectid, async_extent->ram_size, ins.offset, BTRFS_ORDERED_COMPRESSED, async_extent->compress_type); if (ret) { btrfs_drop_extent_cache(BTRFS_I(inode), async_extent->start, async_extent->start + async_extent->ram_size - 1, 0); goto out_free_reserve; } btrfs_dec_block_group_reservations(fs_info, ins.objectid); /* * clear dirty, set writeback and unlock the pages. */ extent_clear_unlock_delalloc(inode, async_extent->start, async_extent->start + async_extent->ram_size - 1, async_extent->start + async_extent->ram_size - 1, NULL, EXTENT_LOCKED | EXTENT_DELALLOC, PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK); if (btrfs_submit_compressed_write(inode, async_extent->start, async_extent->ram_size, ins.objectid, ins.offset, async_extent->pages, async_extent->nr_pages, async_cow->write_flags)) { struct page *p = async_extent->pages[0]; const u64 start = async_extent->start; const u64 end = start + async_extent->ram_size - 1; p->mapping = inode->i_mapping; btrfs_writepage_endio_finish_ordered(p, start, end, 0); p->mapping = NULL; extent_clear_unlock_delalloc(inode, start, end, end, NULL, 0, PAGE_END_WRITEBACK | PAGE_SET_ERROR); free_async_extent_pages(async_extent); } alloc_hint = ins.objectid + ins.offset; kfree(async_extent); cond_resched(); } return; out_free_reserve: btrfs_dec_block_group_reservations(fs_info, ins.objectid); btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); out_free: extent_clear_unlock_delalloc(inode, async_extent->start, async_extent->start + async_extent->ram_size - 1, async_extent->start + async_extent->ram_size - 1, NULL, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK | PAGE_SET_ERROR); free_async_extent_pages(async_extent); kfree(async_extent); goto again; } static u64 get_extent_allocation_hint(struct inode *inode, u64 start, u64 num_bytes) { struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; struct extent_map *em; u64 alloc_hint = 0; read_lock(&em_tree->lock); em = search_extent_mapping(em_tree, start, num_bytes); if (em) { /* * if block start isn't an actual block number then find the * first block in this inode and use that as a hint. If that * block is also bogus then just don't worry about it. */ if (em->block_start >= EXTENT_MAP_LAST_BYTE) { free_extent_map(em); em = search_extent_mapping(em_tree, 0, 0); if (em && em->block_start < EXTENT_MAP_LAST_BYTE) alloc_hint = em->block_start; if (em) free_extent_map(em); } else { alloc_hint = em->block_start; free_extent_map(em); } } read_unlock(&em_tree->lock); return alloc_hint; } /* * when extent_io.c finds a delayed allocation range in the file, * the call backs end up in this code. The basic idea is to * allocate extents on disk for the range, and create ordered data structs * in ram to track those extents. * * locked_page is the page that writepage had locked already. We use * it to make sure we don't do extra locks or unlocks. * * *page_started is set to one if we unlock locked_page and do everything * required to start IO on it. It may be clean and already done with * IO when we return. */ static noinline int cow_file_range(struct inode *inode, struct page *locked_page, u64 start, u64 end, u64 delalloc_end, int *page_started, unsigned long *nr_written, int unlock, struct btrfs_dedupe_hash *hash) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; u64 alloc_hint = 0; u64 num_bytes; unsigned long ram_size; u64 cur_alloc_size = 0; u64 blocksize = fs_info->sectorsize; struct btrfs_key ins; struct extent_map *em; unsigned clear_bits; unsigned long page_ops; bool extent_reserved = false; int ret = 0; if (btrfs_is_free_space_inode(BTRFS_I(inode))) { WARN_ON_ONCE(1); ret = -EINVAL; goto out_unlock; } num_bytes = ALIGN(end - start + 1, blocksize); num_bytes = max(blocksize, num_bytes); ASSERT(num_bytes <= btrfs_super_total_bytes(fs_info->super_copy)); inode_should_defrag(BTRFS_I(inode), start, end, num_bytes, SZ_64K); if (start == 0) { /* lets try to make an inline extent */ ret = cow_file_range_inline(inode, start, end, 0, BTRFS_COMPRESS_NONE, NULL); if (ret == 0) { /* * We use DO_ACCOUNTING here because we need the * delalloc_release_metadata to be run _after_ we drop * our outstanding extent for clearing delalloc for this * range. */ extent_clear_unlock_delalloc(inode, start, end, delalloc_end, NULL, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK); *nr_written = *nr_written + (end - start + PAGE_SIZE) / PAGE_SIZE; *page_started = 1; goto out; } else if (ret < 0) { goto out_unlock; } } alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); btrfs_drop_extent_cache(BTRFS_I(inode), start, start + num_bytes - 1, 0); while (num_bytes > 0) { cur_alloc_size = num_bytes; ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size, fs_info->sectorsize, 0, alloc_hint, &ins, 1, 1); if (ret < 0) goto out_unlock; cur_alloc_size = ins.offset; extent_reserved = true; ram_size = ins.offset; em = create_io_em(inode, start, ins.offset, /* len */ start, /* orig_start */ ins.objectid, /* block_start */ ins.offset, /* block_len */ ins.offset, /* orig_block_len */ ram_size, /* ram_bytes */ BTRFS_COMPRESS_NONE, /* compress_type */ BTRFS_ORDERED_REGULAR /* type */); if (IS_ERR(em)) { ret = PTR_ERR(em); goto out_reserve; } free_extent_map(em); ret = btrfs_add_ordered_extent(inode, start, ins.objectid, ram_size, cur_alloc_size, 0); if (ret) goto out_drop_extent_cache; if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) { ret = btrfs_reloc_clone_csums(inode, start, cur_alloc_size); /* * Only drop cache here, and process as normal. * * We must not allow extent_clear_unlock_delalloc() * at out_unlock label to free meta of this ordered * extent, as its meta should be freed by * btrfs_finish_ordered_io(). * * So we must continue until @start is increased to * skip current ordered extent. */ if (ret) btrfs_drop_extent_cache(BTRFS_I(inode), start, start + ram_size - 1, 0); } btrfs_dec_block_group_reservations(fs_info, ins.objectid); /* we're not doing compressed IO, don't unlock the first * page (which the caller expects to stay locked), don't * clear any dirty bits and don't set any writeback bits * * Do set the Private2 bit so we know this page was properly * setup for writepage */ page_ops = unlock ? PAGE_UNLOCK : 0; page_ops |= PAGE_SET_PRIVATE2; extent_clear_unlock_delalloc(inode, start, start + ram_size - 1, delalloc_end, locked_page, EXTENT_LOCKED | EXTENT_DELALLOC, page_ops); if (num_bytes < cur_alloc_size) num_bytes = 0; else num_bytes -= cur_alloc_size; alloc_hint = ins.objectid + ins.offset; start += cur_alloc_size; extent_reserved = false; /* * btrfs_reloc_clone_csums() error, since start is increased * extent_clear_unlock_delalloc() at out_unlock label won't * free metadata of current ordered extent, we're OK to exit. */ if (ret) goto out_unlock; } out: return ret; out_drop_extent_cache: btrfs_drop_extent_cache(BTRFS_I(inode), start, start + ram_size - 1, 0); out_reserve: btrfs_dec_block_group_reservations(fs_info, ins.objectid); btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); out_unlock: clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV; page_ops = PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK; /* * If we reserved an extent for our delalloc range (or a subrange) and * failed to create the respective ordered extent, then it means that * when we reserved the extent we decremented the extent's size from * the data space_info's bytes_may_use counter and incremented the * space_info's bytes_reserved counter by the same amount. We must make * sure extent_clear_unlock_delalloc() does not try to decrement again * the data space_info's bytes_may_use counter, therefore we do not pass * it the flag EXTENT_CLEAR_DATA_RESV. */ if (extent_reserved) { extent_clear_unlock_delalloc(inode, start, start + cur_alloc_size, start + cur_alloc_size, locked_page, clear_bits, page_ops); start += cur_alloc_size; if (start >= end) goto out; } extent_clear_unlock_delalloc(inode, start, end, delalloc_end, locked_page, clear_bits | EXTENT_CLEAR_DATA_RESV, page_ops); goto out; } /* * work queue call back to started compression on a file and pages */ static noinline void async_cow_start(struct btrfs_work *work) { struct async_cow *async_cow; int num_added = 0; async_cow = container_of(work, struct async_cow, work); compress_file_range(async_cow->inode, async_cow->locked_page, async_cow->start, async_cow->end, async_cow, &num_added); if (num_added == 0) { btrfs_add_delayed_iput(async_cow->inode); async_cow->inode = NULL; } } /* * work queue call back to submit previously compressed pages */ static noinline void async_cow_submit(struct btrfs_work *work) { struct btrfs_fs_info *fs_info; struct async_cow *async_cow; unsigned long nr_pages; async_cow = container_of(work, struct async_cow, work); fs_info = async_cow->fs_info; nr_pages = (async_cow->end - async_cow->start + PAGE_SIZE) >> PAGE_SHIFT; /* atomic_sub_return implies a barrier */ if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) < 5 * SZ_1M) cond_wake_up_nomb(&fs_info->async_submit_wait); if (async_cow->inode) submit_compressed_extents(async_cow->inode, async_cow); } static noinline void async_cow_free(struct btrfs_work *work) { struct async_cow *async_cow; async_cow = container_of(work, struct async_cow, work); if (async_cow->inode) btrfs_add_delayed_iput(async_cow->inode); kfree(async_cow); } static int cow_file_range_async(struct inode *inode, struct page *locked_page, u64 start, u64 end, int *page_started, unsigned long *nr_written, unsigned int write_flags) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct async_cow *async_cow; unsigned long nr_pages; u64 cur_end; clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED, 1, 0, NULL); while (start < end) { async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS); BUG_ON(!async_cow); /* -ENOMEM */ async_cow->inode = igrab(inode); async_cow->fs_info = fs_info; async_cow->locked_page = locked_page; async_cow->start = start; async_cow->write_flags = write_flags; if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS && !btrfs_test_opt(fs_info, FORCE_COMPRESS)) cur_end = end; else cur_end = min(end, start + SZ_512K - 1); async_cow->end = cur_end; INIT_LIST_HEAD(&async_cow->extents); btrfs_init_work(&async_cow->work, btrfs_delalloc_helper, async_cow_start, async_cow_submit, async_cow_free); nr_pages = (cur_end - start + PAGE_SIZE) >> PAGE_SHIFT; atomic_add(nr_pages, &fs_info->async_delalloc_pages); btrfs_queue_work(fs_info->delalloc_workers, &async_cow->work); *nr_written += nr_pages; start = cur_end + 1; } *page_started = 1; return 0; } static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info, u64 bytenr, u64 num_bytes) { int ret; struct btrfs_ordered_sum *sums; LIST_HEAD(list); ret = btrfs_lookup_csums_range(fs_info->csum_root, bytenr, bytenr + num_bytes - 1, &list, 0); if (ret == 0 && list_empty(&list)) return 0; while (!list_empty(&list)) { sums = list_entry(list.next, struct btrfs_ordered_sum, list); list_del(&sums->list); kfree(sums); } if (ret < 0) return ret; return 1; } /* * when nowcow writeback call back. This checks for snapshots or COW copies * of the extents that exist in the file, and COWs the file as required. * * If no cow copies or snapshots exist, we write directly to the existing * blocks on disk */ static noinline int run_delalloc_nocow(struct inode *inode, struct page *locked_page, u64 start, u64 end, int *page_started, int force, unsigned long *nr_written) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_buffer *leaf; struct btrfs_path *path; struct btrfs_file_extent_item *fi; struct btrfs_key found_key; struct extent_map *em; u64 cow_start; u64 cur_offset; u64 extent_end; u64 extent_offset; u64 disk_bytenr; u64 num_bytes; u64 disk_num_bytes; u64 ram_bytes; int extent_type; int ret; int type; int nocow; int check_prev = 1; bool nolock; u64 ino = btrfs_ino(BTRFS_I(inode)); path = btrfs_alloc_path(); if (!path) { extent_clear_unlock_delalloc(inode, start, end, end, locked_page, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK); return -ENOMEM; } nolock = btrfs_is_free_space_inode(BTRFS_I(inode)); cow_start = (u64)-1; cur_offset = start; while (1) { ret = btrfs_lookup_file_extent(NULL, root, path, ino, cur_offset, 0); if (ret < 0) goto error; if (ret > 0 && path->slots[0] > 0 && check_prev) { leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); if (found_key.objectid == ino && found_key.type == BTRFS_EXTENT_DATA_KEY) path->slots[0]--; } check_prev = 0; next_slot: leaf = path->nodes[0]; if (path->slots[0] >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) { if (cow_start != (u64)-1) cur_offset = cow_start; goto error; } if (ret > 0) break; leaf = path->nodes[0]; } nocow = 0; disk_bytenr = 0; num_bytes = 0; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); if (found_key.objectid > ino) break; if (WARN_ON_ONCE(found_key.objectid < ino) || found_key.type < BTRFS_EXTENT_DATA_KEY) { path->slots[0]++; goto next_slot; } if (found_key.type > BTRFS_EXTENT_DATA_KEY || found_key.offset > end) break; if (found_key.offset > cur_offset) { extent_end = found_key.offset; extent_type = 0; goto out_check; } fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); extent_type = btrfs_file_extent_type(leaf, fi); ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); if (extent_type == BTRFS_FILE_EXTENT_REG || extent_type == BTRFS_FILE_EXTENT_PREALLOC) { disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); extent_offset = btrfs_file_extent_offset(leaf, fi); extent_end = found_key.offset + btrfs_file_extent_num_bytes(leaf, fi); disk_num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); if (extent_end <= start) { path->slots[0]++; goto next_slot; } if (disk_bytenr == 0) goto out_check; if (btrfs_file_extent_compression(leaf, fi) || btrfs_file_extent_encryption(leaf, fi) || btrfs_file_extent_other_encoding(leaf, fi)) goto out_check; /* * Do the same check as in btrfs_cross_ref_exist but * without the unnecessary search. */ if (!nolock && btrfs_file_extent_generation(leaf, fi) <= btrfs_root_last_snapshot(&root->root_item)) goto out_check; if (extent_type == BTRFS_FILE_EXTENT_REG && !force) goto out_check; if (btrfs_extent_readonly(fs_info, disk_bytenr)) goto out_check; ret = btrfs_cross_ref_exist(root, ino, found_key.offset - extent_offset, disk_bytenr); if (ret) { /* * ret could be -EIO if the above fails to read * metadata. */ if (ret < 0) { if (cow_start != (u64)-1) cur_offset = cow_start; goto error; } WARN_ON_ONCE(nolock); goto out_check; } disk_bytenr += extent_offset; disk_bytenr += cur_offset - found_key.offset; num_bytes = min(end + 1, extent_end) - cur_offset; /* * if there are pending snapshots for this root, * we fall into common COW way. */ if (!nolock && atomic_read(&root->snapshot_force_cow)) goto out_check; /* * force cow if csum exists in the range. * this ensure that csum for a given extent are * either valid or do not exist. */ ret = csum_exist_in_range(fs_info, disk_bytenr, num_bytes); if (ret) { /* * ret could be -EIO if the above fails to read * metadata. */ if (ret < 0) { if (cow_start != (u64)-1) cur_offset = cow_start; goto error; } WARN_ON_ONCE(nolock); goto out_check; } if (!btrfs_inc_nocow_writers(fs_info, disk_bytenr)) goto out_check; nocow = 1; } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { extent_end = found_key.offset + btrfs_file_extent_ram_bytes(leaf, fi); extent_end = ALIGN(extent_end, fs_info->sectorsize); } else { BUG_ON(1); } out_check: if (extent_end <= start) { path->slots[0]++; if (nocow) btrfs_dec_nocow_writers(fs_info, disk_bytenr); goto next_slot; } if (!nocow) { if (cow_start == (u64)-1) cow_start = cur_offset; cur_offset = extent_end; if (cur_offset > end) break; path->slots[0]++; goto next_slot; } btrfs_release_path(path); if (cow_start != (u64)-1) { ret = cow_file_range(inode, locked_page, cow_start, found_key.offset - 1, end, page_started, nr_written, 1, NULL); if (ret) { if (nocow) btrfs_dec_nocow_writers(fs_info, disk_bytenr); goto error; } cow_start = (u64)-1; } if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { u64 orig_start = found_key.offset - extent_offset; em = create_io_em(inode, cur_offset, num_bytes, orig_start, disk_bytenr, /* block_start */ num_bytes, /* block_len */ disk_num_bytes, /* orig_block_len */ ram_bytes, BTRFS_COMPRESS_NONE, BTRFS_ORDERED_PREALLOC); if (IS_ERR(em)) { if (nocow) btrfs_dec_nocow_writers(fs_info, disk_bytenr); ret = PTR_ERR(em); goto error; } free_extent_map(em); } if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { type = BTRFS_ORDERED_PREALLOC; } else { type = BTRFS_ORDERED_NOCOW; } ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr, num_bytes, num_bytes, type); if (nocow) btrfs_dec_nocow_writers(fs_info, disk_bytenr); BUG_ON(ret); /* -ENOMEM */ if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) /* * Error handled later, as we must prevent * extent_clear_unlock_delalloc() in error handler * from freeing metadata of created ordered extent. */ ret = btrfs_reloc_clone_csums(inode, cur_offset, num_bytes); extent_clear_unlock_delalloc(inode, cur_offset, cur_offset + num_bytes - 1, end, locked_page, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_CLEAR_DATA_RESV, PAGE_UNLOCK | PAGE_SET_PRIVATE2); cur_offset = extent_end; /* * btrfs_reloc_clone_csums() error, now we're OK to call error * handler, as metadata for created ordered extent will only * be freed by btrfs_finish_ordered_io(). */ if (ret) goto error; if (cur_offset > end) break; } btrfs_release_path(path); if (cur_offset <= end && cow_start == (u64)-1) cow_start = cur_offset; if (cow_start != (u64)-1) { cur_offset = end; ret = cow_file_range(inode, locked_page, cow_start, end, end, page_started, nr_written, 1, NULL); if (ret) goto error; } error: if (ret && cur_offset < end) extent_clear_unlock_delalloc(inode, cur_offset, end, end, locked_page, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK); btrfs_free_path(path); return ret; } static inline int need_force_cow(struct inode *inode, u64 start, u64 end) { if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && !(BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)) return 0; /* * @defrag_bytes is a hint value, no spinlock held here, * if is not zero, it means the file is defragging. * Force cow if given extent needs to be defragged. */ if (BTRFS_I(inode)->defrag_bytes && test_range_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_DEFRAG, 0, NULL)) return 1; return 0; } /* * Function to process delayed allocation (create CoW) for ranges which are * being touched for the first time. */ int btrfs_run_delalloc_range(void *private_data, struct page *locked_page, u64 start, u64 end, int *page_started, unsigned long *nr_written, struct writeback_control *wbc) { struct inode *inode = private_data; int ret; int force_cow = need_force_cow(inode, start, end); unsigned int write_flags = wbc_to_write_flags(wbc); if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW && !force_cow) { ret = run_delalloc_nocow(inode, locked_page, start, end, page_started, 1, nr_written); } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC && !force_cow) { ret = run_delalloc_nocow(inode, locked_page, start, end, page_started, 0, nr_written); } else if (!inode_need_compress(inode, start, end)) { ret = cow_file_range(inode, locked_page, start, end, end, page_started, nr_written, 1, NULL); } else { set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &BTRFS_I(inode)->runtime_flags); ret = cow_file_range_async(inode, locked_page, start, end, page_started, nr_written, write_flags); } if (ret) btrfs_cleanup_ordered_extents(inode, locked_page, start, end - start + 1); return ret; } void btrfs_split_delalloc_extent(struct inode *inode, struct extent_state *orig, u64 split) { u64 size; /* not delalloc, ignore it */ if (!(orig->state & EXTENT_DELALLOC)) return; size = orig->end - orig->start + 1; if (size > BTRFS_MAX_EXTENT_SIZE) { u32 num_extents; u64 new_size; /* * See the explanation in btrfs_merge_delalloc_extent, the same * applies here, just in reverse. */ new_size = orig->end - split + 1; num_extents = count_max_extents(new_size); new_size = split - orig->start; num_extents += count_max_extents(new_size); if (count_max_extents(size) >= num_extents) return; } spin_lock(&BTRFS_I(inode)->lock); btrfs_mod_outstanding_extents(BTRFS_I(inode), 1); spin_unlock(&BTRFS_I(inode)->lock); } /* * Handle merged delayed allocation extents so we can keep track of new extents * that are just merged onto old extents, such as when we are doing sequential * writes, so we can properly account for the metadata space we'll need. */ void btrfs_merge_delalloc_extent(struct inode *inode, struct extent_state *new, struct extent_state *other) { u64 new_size, old_size; u32 num_extents; /* not delalloc, ignore it */ if (!(other->state & EXTENT_DELALLOC)) return; if (new->start > other->start) new_size = new->end - other->start + 1; else new_size = other->end - new->start + 1; /* we're not bigger than the max, unreserve the space and go */ if (new_size <= BTRFS_MAX_EXTENT_SIZE) { spin_lock(&BTRFS_I(inode)->lock); btrfs_mod_outstanding_extents(BTRFS_I(inode), -1); spin_unlock(&BTRFS_I(inode)->lock); return; } /* * We have to add up either side to figure out how many extents were * accounted for before we merged into one big extent. If the number of * extents we accounted for is <= the amount we need for the new range * then we can return, otherwise drop. Think of it like this * * [ 4k][MAX_SIZE] * * So we've grown the extent by a MAX_SIZE extent, this would mean we * need 2 outstanding extents, on one side we have 1 and the other side * we have 1 so they are == and we can return. But in this case * * [MAX_SIZE+4k][MAX_SIZE+4k] * * Each range on their own accounts for 2 extents, but merged together * they are only 3 extents worth of accounting, so we need to drop in * this case. */ old_size = other->end - other->start + 1; num_extents = count_max_extents(old_size); old_size = new->end - new->start + 1; num_extents += count_max_extents(old_size); if (count_max_extents(new_size) >= num_extents) return; spin_lock(&BTRFS_I(inode)->lock); btrfs_mod_outstanding_extents(BTRFS_I(inode), -1); spin_unlock(&BTRFS_I(inode)->lock); } static void btrfs_add_delalloc_inodes(struct btrfs_root *root, struct inode *inode) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); spin_lock(&root->delalloc_lock); if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) { list_add_tail(&BTRFS_I(inode)->delalloc_inodes, &root->delalloc_inodes); set_bit(BTRFS_INODE_IN_DELALLOC_LIST, &BTRFS_I(inode)->runtime_flags); root->nr_delalloc_inodes++; if (root->nr_delalloc_inodes == 1) { spin_lock(&fs_info->delalloc_root_lock); BUG_ON(!list_empty(&root->delalloc_root)); list_add_tail(&root->delalloc_root, &fs_info->delalloc_roots); spin_unlock(&fs_info->delalloc_root_lock); } } spin_unlock(&root->delalloc_lock); } void __btrfs_del_delalloc_inode(struct btrfs_root *root, struct btrfs_inode *inode) { struct btrfs_fs_info *fs_info = root->fs_info; if (!list_empty(&inode->delalloc_inodes)) { list_del_init(&inode->delalloc_inodes); clear_bit(BTRFS_INODE_IN_DELALLOC_LIST, &inode->runtime_flags); root->nr_delalloc_inodes--; if (!root->nr_delalloc_inodes) { ASSERT(list_empty(&root->delalloc_inodes)); spin_lock(&fs_info->delalloc_root_lock); BUG_ON(list_empty(&root->delalloc_root)); list_del_init(&root->delalloc_root); spin_unlock(&fs_info->delalloc_root_lock); } } } static void btrfs_del_delalloc_inode(struct btrfs_root *root, struct btrfs_inode *inode) { spin_lock(&root->delalloc_lock); __btrfs_del_delalloc_inode(root, inode); spin_unlock(&root->delalloc_lock); } /* * Properly track delayed allocation bytes in the inode and to maintain the * list of inodes that have pending delalloc work to be done. */ void btrfs_set_delalloc_extent(struct inode *inode, struct extent_state *state, unsigned *bits) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC)) WARN_ON(1); /* * set_bit and clear bit hooks normally require _irqsave/restore * but in this case, we are only testing for the DELALLOC * bit, which is only set or cleared with irqs on */ if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { struct btrfs_root *root = BTRFS_I(inode)->root; u64 len = state->end + 1 - state->start; u32 num_extents = count_max_extents(len); bool do_list = !btrfs_is_free_space_inode(BTRFS_I(inode)); spin_lock(&BTRFS_I(inode)->lock); btrfs_mod_outstanding_extents(BTRFS_I(inode), num_extents); spin_unlock(&BTRFS_I(inode)->lock); /* For sanity tests */ if (btrfs_is_testing(fs_info)) return; percpu_counter_add_batch(&fs_info->delalloc_bytes, len, fs_info->delalloc_batch); spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->delalloc_bytes += len; if (*bits & EXTENT_DEFRAG) BTRFS_I(inode)->defrag_bytes += len; if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST, &BTRFS_I(inode)->runtime_flags)) btrfs_add_delalloc_inodes(root, inode); spin_unlock(&BTRFS_I(inode)->lock); } if (!(state->state & EXTENT_DELALLOC_NEW) && (*bits & EXTENT_DELALLOC_NEW)) { spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->new_delalloc_bytes += state->end + 1 - state->start; spin_unlock(&BTRFS_I(inode)->lock); } } /* * Once a range is no longer delalloc this function ensures that proper * accounting happens. */ void btrfs_clear_delalloc_extent(struct inode *vfs_inode, struct extent_state *state, unsigned *bits) { struct btrfs_inode *inode = BTRFS_I(vfs_inode); struct btrfs_fs_info *fs_info = btrfs_sb(vfs_inode->i_sb); u64 len = state->end + 1 - state->start; u32 num_extents = count_max_extents(len); if ((state->state & EXTENT_DEFRAG) && (*bits & EXTENT_DEFRAG)) { spin_lock(&inode->lock); inode->defrag_bytes -= len; spin_unlock(&inode->lock); } /* * set_bit and clear bit hooks normally require _irqsave/restore * but in this case, we are only testing for the DELALLOC * bit, which is only set or cleared with irqs on */ if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { struct btrfs_root *root = inode->root; bool do_list = !btrfs_is_free_space_inode(inode); spin_lock(&inode->lock); btrfs_mod_outstanding_extents(inode, -num_extents); spin_unlock(&inode->lock); /* * We don't reserve metadata space for space cache inodes so we * don't need to call delalloc_release_metadata if there is an * error. */ if (*bits & EXTENT_CLEAR_META_RESV && root != fs_info->tree_root) btrfs_delalloc_release_metadata(inode, len, false); /* For sanity tests. */ if (btrfs_is_testing(fs_info)) return; if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID && do_list && !(state->state & EXTENT_NORESERVE) && (*bits & EXTENT_CLEAR_DATA_RESV)) btrfs_free_reserved_data_space_noquota( &inode->vfs_inode, state->start, len); percpu_counter_add_batch(&fs_info->delalloc_bytes, -len, fs_info->delalloc_batch); spin_lock(&inode->lock); inode->delalloc_bytes -= len; if (do_list && inode->delalloc_bytes == 0 && test_bit(BTRFS_INODE_IN_DELALLOC_LIST, &inode->runtime_flags)) btrfs_del_delalloc_inode(root, inode); spin_unlock(&inode->lock); } if ((state->state & EXTENT_DELALLOC_NEW) && (*bits & EXTENT_DELALLOC_NEW)) { spin_lock(&inode->lock); ASSERT(inode->new_delalloc_bytes >= len); inode->new_delalloc_bytes -= len; spin_unlock(&inode->lock); } } /* * btrfs_bio_fits_in_stripe - Checks whether the size of the given bio will fit * in a chunk's stripe. This function ensures that bios do not span a * stripe/chunk * * @page - The page we are about to add to the bio * @size - size we want to add to the bio * @bio - bio we want to ensure is smaller than a stripe * @bio_flags - flags of the bio * * return 1 if page cannot be added to the bio * return 0 if page can be added to the bio * return error otherwise */ int btrfs_bio_fits_in_stripe(struct page *page, size_t size, struct bio *bio, unsigned long bio_flags) { struct inode *inode = page->mapping->host; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); u64 logical = (u64)bio->bi_iter.bi_sector << 9; u64 length = 0; u64 map_length; int ret; if (bio_flags & EXTENT_BIO_COMPRESSED) return 0; length = bio->bi_iter.bi_size; map_length = length; ret = btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length, NULL, 0); if (ret < 0) return ret; if (map_length < length + size) return 1; return 0; } /* * in order to insert checksums into the metadata in large chunks, * we wait until bio submission time. All the pages in the bio are * checksummed and sums are attached onto the ordered extent record. * * At IO completion time the cums attached on the ordered extent record * are inserted into the btree */ static blk_status_t btrfs_submit_bio_start(void *private_data, struct bio *bio, u64 bio_offset) { struct inode *inode = private_data; blk_status_t ret = 0; ret = btrfs_csum_one_bio(inode, bio, 0, 0); BUG_ON(ret); /* -ENOMEM */ return 0; } /* * extent_io.c submission hook. This does the right thing for csum calculation * on write, or reading the csums from the tree before a read. * * Rules about async/sync submit, * a) read: sync submit * * b) write without checksum: sync submit * * c) write with checksum: * c-1) if bio is issued by fsync: sync submit * (sync_writers != 0) * * c-2) if root is reloc root: sync submit * (only in case of buffered IO) * * c-3) otherwise: async submit */ static blk_status_t btrfs_submit_bio_hook(void *private_data, struct bio *bio, int mirror_num, unsigned long bio_flags, u64 bio_offset) { struct inode *inode = private_data; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; enum btrfs_wq_endio_type metadata = BTRFS_WQ_ENDIO_DATA; blk_status_t ret = 0; int skip_sum; int async = !atomic_read(&BTRFS_I(inode)->sync_writers); skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; if (btrfs_is_free_space_inode(BTRFS_I(inode))) metadata = BTRFS_WQ_ENDIO_FREE_SPACE; if (bio_op(bio) != REQ_OP_WRITE) { ret = btrfs_bio_wq_end_io(fs_info, bio, metadata); if (ret) goto out; if (bio_flags & EXTENT_BIO_COMPRESSED) { ret = btrfs_submit_compressed_read(inode, bio, mirror_num, bio_flags); goto out; } else if (!skip_sum) { ret = btrfs_lookup_bio_sums(inode, bio, NULL); if (ret) goto out; } goto mapit; } else if (async && !skip_sum) { /* csum items have already been cloned */ if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) goto mapit; /* we're doing a write, do the async checksumming */ ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, bio_flags, bio_offset, inode, btrfs_submit_bio_start); goto out; } else if (!skip_sum) { ret = btrfs_csum_one_bio(inode, bio, 0, 0); if (ret) goto out; } mapit: ret = btrfs_map_bio(fs_info, bio, mirror_num, 0); out: if (ret) { bio->bi_status = ret; bio_endio(bio); } return ret; } /* * given a list of ordered sums record them in the inode. This happens * at IO completion time based on sums calculated at bio submission time. */ static noinline int add_pending_csums(struct btrfs_trans_handle *trans, struct inode *inode, struct list_head *list) { struct btrfs_ordered_sum *sum; int ret; list_for_each_entry(sum, list, list) { trans->adding_csums = true; ret = btrfs_csum_file_blocks(trans, BTRFS_I(inode)->root->fs_info->csum_root, sum); trans->adding_csums = false; if (ret) return ret; } return 0; } int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end, unsigned int extra_bits, struct extent_state **cached_state, int dedupe) { WARN_ON(PAGE_ALIGNED(end)); return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end, extra_bits, cached_state); } /* see btrfs_writepage_start_hook for details on why this is required */ struct btrfs_writepage_fixup { struct page *page; struct btrfs_work work; }; static void btrfs_writepage_fixup_worker(struct btrfs_work *work) { struct btrfs_writepage_fixup *fixup; struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; struct extent_changeset *data_reserved = NULL; struct page *page; struct inode *inode; u64 page_start; u64 page_end; int ret; fixup = container_of(work, struct btrfs_writepage_fixup, work); page = fixup->page; again: lock_page(page); if (!page->mapping || !PageDirty(page) || !PageChecked(page)) { ClearPageChecked(page); goto out_page; } inode = page->mapping->host; page_start = page_offset(page); page_end = page_offset(page) + PAGE_SIZE - 1; lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, &cached_state); /* already ordered? We're done */ if (PagePrivate2(page)) goto out; ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start, PAGE_SIZE); if (ordered) { unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, &cached_state); unlock_page(page); btrfs_start_ordered_extent(inode, ordered, 1); btrfs_put_ordered_extent(ordered); goto again; } ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start, PAGE_SIZE); if (ret) { mapping_set_error(page->mapping, ret); end_extent_writepage(page, ret, page_start, page_end); ClearPageChecked(page); goto out; } ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0, &cached_state, 0); if (ret) { mapping_set_error(page->mapping, ret); end_extent_writepage(page, ret, page_start, page_end); ClearPageChecked(page); goto out; } ClearPageChecked(page); set_page_dirty(page); btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, false); out: unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, &cached_state); out_page: unlock_page(page); put_page(page); kfree(fixup); extent_changeset_free(data_reserved); } /* * There are a few paths in the higher layers of the kernel that directly * set the page dirty bit without asking the filesystem if it is a * good idea. This causes problems because we want to make sure COW * properly happens and the data=ordered rules are followed. * * In our case any range that doesn't have the ORDERED bit set * hasn't been properly setup for IO. We kick off an async process * to fix it up. The async helper will wait for ordered extents, set * the delalloc bit and make it safe to write the page. */ int btrfs_writepage_cow_fixup(struct page *page, u64 start, u64 end) { struct inode *inode = page->mapping->host; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_writepage_fixup *fixup; /* this page is properly in the ordered list */ if (TestClearPagePrivate2(page)) return 0; if (PageChecked(page)) return -EAGAIN; fixup = kzalloc(sizeof(*fixup), GFP_NOFS); if (!fixup) return -EAGAIN; SetPageChecked(page); get_page(page); btrfs_init_work(&fixup->work, btrfs_fixup_helper, btrfs_writepage_fixup_worker, NULL, NULL); fixup->page = page; btrfs_queue_work(fs_info->fixup_workers, &fixup->work); return -EBUSY; } static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, struct inode *inode, u64 file_pos, u64 disk_bytenr, u64 disk_num_bytes, u64 num_bytes, u64 ram_bytes, u8 compression, u8 encryption, u16 other_encoding, int extent_type) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_file_extent_item *fi; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key ins; u64 qg_released; int extent_inserted = 0; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; /* * we may be replacing one extent in the tree with another. * The new extent is pinned in the extent map, and we don't want * to drop it from the cache until it is completely in the btree. * * So, tell btrfs_drop_extents to leave this extent in the cache. * the caller is expected to unpin it and allow it to be merged * with the others. */ ret = __btrfs_drop_extents(trans, root, inode, path, file_pos, file_pos + num_bytes, NULL, 0, 1, sizeof(*fi), &extent_inserted); if (ret) goto out; if (!extent_inserted) { ins.objectid = btrfs_ino(BTRFS_I(inode)); ins.offset = file_pos; ins.type = BTRFS_EXTENT_DATA_KEY; path->leave_spinning = 1; ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi)); if (ret) goto out; } leaf = path->nodes[0]; fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_type(leaf, fi, extent_type); btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr); btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes); btrfs_set_file_extent_offset(leaf, fi, 0); btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes); btrfs_set_file_extent_compression(leaf, fi, compression); btrfs_set_file_extent_encryption(leaf, fi, encryption); btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding); btrfs_mark_buffer_dirty(leaf); btrfs_release_path(path); inode_add_bytes(inode, num_bytes); ins.objectid = disk_bytenr; ins.offset = disk_num_bytes; ins.type = BTRFS_EXTENT_ITEM_KEY; /* * Release the reserved range from inode dirty range map, as it is * already moved into delayed_ref_head */ ret = btrfs_qgroup_release_data(inode, file_pos, ram_bytes); if (ret < 0) goto out; qg_released = ret; ret = btrfs_alloc_reserved_file_extent(trans, root, btrfs_ino(BTRFS_I(inode)), file_pos, qg_released, &ins); out: btrfs_free_path(path); return ret; } /* snapshot-aware defrag */ struct sa_defrag_extent_backref { struct rb_node node; struct old_sa_defrag_extent *old; u64 root_id; u64 inum; u64 file_pos; u64 extent_offset; u64 num_bytes; u64 generation; }; struct old_sa_defrag_extent { struct list_head list; struct new_sa_defrag_extent *new; u64 extent_offset; u64 bytenr; u64 offset; u64 len; int count; }; struct new_sa_defrag_extent { struct rb_root root; struct list_head head; struct btrfs_path *path; struct inode *inode; u64 file_pos; u64 len; u64 bytenr; u64 disk_len; u8 compress_type; }; static int backref_comp(struct sa_defrag_extent_backref *b1, struct sa_defrag_extent_backref *b2) { if (b1->root_id < b2->root_id) return -1; else if (b1->root_id > b2->root_id) return 1; if (b1->inum < b2->inum) return -1; else if (b1->inum > b2->inum) return 1; if (b1->file_pos < b2->file_pos) return -1; else if (b1->file_pos > b2->file_pos) return 1; /* * [------------------------------] ===> (a range of space) * |<--->| |<---->| =============> (fs/file tree A) * |<---------------------------->| ===> (fs/file tree B) * * A range of space can refer to two file extents in one tree while * refer to only one file extent in another tree. * * So we may process a disk offset more than one time(two extents in A) * and locate at the same extent(one extent in B), then insert two same * backrefs(both refer to the extent in B). */ return 0; } static void backref_insert(struct rb_root *root, struct sa_defrag_extent_backref *backref) { struct rb_node **p = &root->rb_node; struct rb_node *parent = NULL; struct sa_defrag_extent_backref *entry; int ret; while (*p) { parent = *p; entry = rb_entry(parent, struct sa_defrag_extent_backref, node); ret = backref_comp(backref, entry); if (ret < 0) p = &(*p)->rb_left; else p = &(*p)->rb_right; } rb_link_node(&backref->node, parent, p); rb_insert_color(&backref->node, root); } /* * Note the backref might has changed, and in this case we just return 0. */ static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id, void *ctx) { struct btrfs_file_extent_item *extent; struct old_sa_defrag_extent *old = ctx; struct new_sa_defrag_extent *new = old->new; struct btrfs_path *path = new->path; struct btrfs_key key; struct btrfs_root *root; struct sa_defrag_extent_backref *backref; struct extent_buffer *leaf; struct inode *inode = new->inode; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); int slot; int ret; u64 extent_offset; u64 num_bytes; if (BTRFS_I(inode)->root->root_key.objectid == root_id && inum == btrfs_ino(BTRFS_I(inode))) return 0; key.objectid = root_id; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = (u64)-1; root = btrfs_read_fs_root_no_name(fs_info, &key); if (IS_ERR(root)) { if (PTR_ERR(root) == -ENOENT) return 0; WARN_ON(1); btrfs_debug(fs_info, "inum=%llu, offset=%llu, root_id=%llu", inum, offset, root_id); return PTR_ERR(root); } key.objectid = inum; key.type = BTRFS_EXTENT_DATA_KEY; if (offset > (u64)-1 << 32) key.offset = 0; else key.offset = offset; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (WARN_ON(ret < 0)) return ret; ret = 0; while (1) { cond_resched(); leaf = path->nodes[0]; slot = path->slots[0]; if (slot >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) { goto out; } else if (ret > 0) { ret = 0; goto out; } continue; } path->slots[0]++; btrfs_item_key_to_cpu(leaf, &key, slot); if (key.objectid > inum) goto out; if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY) continue; extent = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr) continue; /* * 'offset' refers to the exact key.offset, * NOT the 'offset' field in btrfs_extent_data_ref, ie. * (key.offset - extent_offset). */ if (key.offset != offset) continue; extent_offset = btrfs_file_extent_offset(leaf, extent); num_bytes = btrfs_file_extent_num_bytes(leaf, extent); if (extent_offset >= old->extent_offset + old->offset + old->len || extent_offset + num_bytes <= old->extent_offset + old->offset) continue; break; } backref = kmalloc(sizeof(*backref), GFP_NOFS); if (!backref) { ret = -ENOENT; goto out; } backref->root_id = root_id; backref->inum = inum; backref->file_pos = offset; backref->num_bytes = num_bytes; backref->extent_offset = extent_offset; backref->generation = btrfs_file_extent_generation(leaf, extent); backref->old = old; backref_insert(&new->root, backref); old->count++; out: btrfs_release_path(path); WARN_ON(ret); return ret; } static noinline bool record_extent_backrefs(struct btrfs_path *path, struct new_sa_defrag_extent *new) { struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); struct old_sa_defrag_extent *old, *tmp; int ret; new->path = path; list_for_each_entry_safe(old, tmp, &new->head, list) { ret = iterate_inodes_from_logical(old->bytenr + old->extent_offset, fs_info, path, record_one_backref, old, false); if (ret < 0 && ret != -ENOENT) return false; /* no backref to be processed for this extent */ if (!old->count) { list_del(&old->list); kfree(old); } } if (list_empty(&new->head)) return false; return true; } static int relink_is_mergable(struct extent_buffer *leaf, struct btrfs_file_extent_item *fi, struct new_sa_defrag_extent *new) { if (btrfs_file_extent_disk_bytenr(leaf, fi) != new->bytenr) return 0; if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG) return 0; if (btrfs_file_extent_compression(leaf, fi) != new->compress_type) return 0; if (btrfs_file_extent_encryption(leaf, fi) || btrfs_file_extent_other_encoding(leaf, fi)) return 0; return 1; } /* * Note the backref might has changed, and in this case we just return 0. */ static noinline int relink_extent_backref(struct btrfs_path *path, struct sa_defrag_extent_backref *prev, struct sa_defrag_extent_backref *backref) { struct btrfs_file_extent_item *extent; struct btrfs_file_extent_item *item; struct btrfs_ordered_extent *ordered; struct btrfs_trans_handle *trans; struct btrfs_root *root; struct btrfs_key key; struct extent_buffer *leaf; struct old_sa_defrag_extent *old = backref->old; struct new_sa_defrag_extent *new = old->new; struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); struct inode *inode; struct extent_state *cached = NULL; int ret = 0; u64 start; u64 len; u64 lock_start; u64 lock_end; bool merge = false; int index; if (prev && prev->root_id == backref->root_id && prev->inum == backref->inum && prev->file_pos + prev->num_bytes == backref->file_pos) merge = true; /* step 1: get root */ key.objectid = backref->root_id; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = (u64)-1; index = srcu_read_lock(&fs_info->subvol_srcu); root = btrfs_read_fs_root_no_name(fs_info, &key); if (IS_ERR(root)) { srcu_read_unlock(&fs_info->subvol_srcu, index); if (PTR_ERR(root) == -ENOENT) return 0; return PTR_ERR(root); } if (btrfs_root_readonly(root)) { srcu_read_unlock(&fs_info->subvol_srcu, index); return 0; } /* step 2: get inode */ key.objectid = backref->inum; key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; inode = btrfs_iget(fs_info->sb, &key, root, NULL); if (IS_ERR(inode)) { srcu_read_unlock(&fs_info->subvol_srcu, index); return 0; } srcu_read_unlock(&fs_info->subvol_srcu, index); /* step 3: relink backref */ lock_start = backref->file_pos; lock_end = backref->file_pos + backref->num_bytes - 1; lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end, &cached); ordered = btrfs_lookup_first_ordered_extent(inode, lock_end); if (ordered) { btrfs_put_ordered_extent(ordered); goto out_unlock; } trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_unlock; } key.objectid = backref->inum; key.type = BTRFS_EXTENT_DATA_KEY; key.offset = backref->file_pos; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) { goto out_free_path; } else if (ret > 0) { ret = 0; goto out_free_path; } extent = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_file_extent_item); if (btrfs_file_extent_generation(path->nodes[0], extent) != backref->generation) goto out_free_path; btrfs_release_path(path); start = backref->file_pos; if (backref->extent_offset < old->extent_offset + old->offset) start += old->extent_offset + old->offset - backref->extent_offset; len = min(backref->extent_offset + backref->num_bytes, old->extent_offset + old->offset + old->len); len -= max(backref->extent_offset, old->extent_offset + old->offset); ret = btrfs_drop_extents(trans, root, inode, start, start + len, 1); if (ret) goto out_free_path; again: key.objectid = btrfs_ino(BTRFS_I(inode)); key.type = BTRFS_EXTENT_DATA_KEY; key.offset = start; path->leave_spinning = 1; if (merge) { struct btrfs_file_extent_item *fi; u64 extent_len; struct btrfs_key found_key; ret = btrfs_search_slot(trans, root, &key, path, 0, 1); if (ret < 0) goto out_free_path; path->slots[0]--; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); extent_len = btrfs_file_extent_num_bytes(leaf, fi); if (extent_len + found_key.offset == start && relink_is_mergable(leaf, fi, new)) { btrfs_set_file_extent_num_bytes(leaf, fi, extent_len + len); btrfs_mark_buffer_dirty(leaf); inode_add_bytes(inode, len); ret = 1; goto out_free_path; } else { merge = false; btrfs_release_path(path); goto again; } } ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*extent)); if (ret) { btrfs_abort_transaction(trans, ret); goto out_free_path; } leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr); btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len); btrfs_set_file_extent_offset(leaf, item, start - new->file_pos); btrfs_set_file_extent_num_bytes(leaf, item, len); btrfs_set_file_extent_ram_bytes(leaf, item, new->len); btrfs_set_file_extent_generation(leaf, item, trans->transid); btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG); btrfs_set_file_extent_compression(leaf, item, new->compress_type); btrfs_set_file_extent_encryption(leaf, item, 0); btrfs_set_file_extent_other_encoding(leaf, item, 0); btrfs_mark_buffer_dirty(leaf); inode_add_bytes(inode, len); btrfs_release_path(path); ret = btrfs_inc_extent_ref(trans, root, new->bytenr, new->disk_len, 0, backref->root_id, backref->inum, new->file_pos); /* start - extent_offset */ if (ret) { btrfs_abort_transaction(trans, ret); goto out_free_path; } ret = 1; out_free_path: btrfs_release_path(path); path->leave_spinning = 0; btrfs_end_transaction(trans); out_unlock: unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end, &cached); iput(inode); return ret; } static void free_sa_defrag_extent(struct new_sa_defrag_extent *new) { struct old_sa_defrag_extent *old, *tmp; if (!new) return; list_for_each_entry_safe(old, tmp, &new->head, list) { kfree(old); } kfree(new); } static void relink_file_extents(struct new_sa_defrag_extent *new) { struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); struct btrfs_path *path; struct sa_defrag_extent_backref *backref; struct sa_defrag_extent_backref *prev = NULL; struct rb_node *node; int ret; path = btrfs_alloc_path(); if (!path) return; if (!record_extent_backrefs(path, new)) { btrfs_free_path(path); goto out; } btrfs_release_path(path); while (1) { node = rb_first(&new->root); if (!node) break; rb_erase(node, &new->root); backref = rb_entry(node, struct sa_defrag_extent_backref, node); ret = relink_extent_backref(path, prev, backref); WARN_ON(ret < 0); kfree(prev); if (ret == 1) prev = backref; else prev = NULL; cond_resched(); } kfree(prev); btrfs_free_path(path); out: free_sa_defrag_extent(new); atomic_dec(&fs_info->defrag_running); wake_up(&fs_info->transaction_wait); } static struct new_sa_defrag_extent * record_old_file_extents(struct inode *inode, struct btrfs_ordered_extent *ordered) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_path *path; struct btrfs_key key; struct old_sa_defrag_extent *old; struct new_sa_defrag_extent *new; int ret; new = kmalloc(sizeof(*new), GFP_NOFS); if (!new) return NULL; new->inode = inode; new->file_pos = ordered->file_offset; new->len = ordered->len; new->bytenr = ordered->start; new->disk_len = ordered->disk_len; new->compress_type = ordered->compress_type; new->root = RB_ROOT; INIT_LIST_HEAD(&new->head); path = btrfs_alloc_path(); if (!path) goto out_kfree; key.objectid = btrfs_ino(BTRFS_I(inode)); key.type = BTRFS_EXTENT_DATA_KEY; key.offset = new->file_pos; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out_free_path; if (ret > 0 && path->slots[0] > 0) path->slots[0]--; /* find out all the old extents for the file range */ while (1) { struct btrfs_file_extent_item *extent; struct extent_buffer *l; int slot; u64 num_bytes; u64 offset; u64 end; u64 disk_bytenr; u64 extent_offset; l = path->nodes[0]; slot = path->slots[0]; if (slot >= btrfs_header_nritems(l)) { ret = btrfs_next_leaf(root, path); if (ret < 0) goto out_free_path; else if (ret > 0) break; continue; } btrfs_item_key_to_cpu(l, &key, slot); if (key.objectid != btrfs_ino(BTRFS_I(inode))) break; if (key.type != BTRFS_EXTENT_DATA_KEY) break; if (key.offset >= new->file_pos + new->len) break; extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item); num_bytes = btrfs_file_extent_num_bytes(l, extent); if (key.offset + num_bytes < new->file_pos) goto next; disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent); if (!disk_bytenr) goto next; extent_offset = btrfs_file_extent_offset(l, extent); old = kmalloc(sizeof(*old), GFP_NOFS); if (!old) goto out_free_path; offset = max(new->file_pos, key.offset); end = min(new->file_pos + new->len, key.offset + num_bytes); old->bytenr = disk_bytenr; old->extent_offset = extent_offset; old->offset = offset - key.offset; old->len = end - offset; old->new = new; old->count = 0; list_add_tail(&old->list, &new->head); next: path->slots[0]++; cond_resched(); } btrfs_free_path(path); atomic_inc(&fs_info->defrag_running); return new; out_free_path: btrfs_free_path(path); out_kfree: free_sa_defrag_extent(new); return NULL; } static void btrfs_release_delalloc_bytes(struct btrfs_fs_info *fs_info, u64 start, u64 len) { struct btrfs_block_group_cache *cache; cache = btrfs_lookup_block_group(fs_info, start); ASSERT(cache); spin_lock(&cache->lock); cache->delalloc_bytes -= len; spin_unlock(&cache->lock); btrfs_put_block_group(cache); } /* as ordered data IO finishes, this gets called so we can finish * an ordered extent if the range of bytes in the file it covers are * fully written. */ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent) { struct inode *inode = ordered_extent->inode; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans = NULL; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_state *cached_state = NULL; struct new_sa_defrag_extent *new = NULL; int compress_type = 0; int ret = 0; u64 logical_len = ordered_extent->len; bool nolock; bool truncated = false; bool range_locked = false; bool clear_new_delalloc_bytes = false; bool clear_reserved_extent = true; if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags) && !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags)) clear_new_delalloc_bytes = true; nolock = btrfs_is_free_space_inode(BTRFS_I(inode)); if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) { ret = -EIO; goto out; } btrfs_free_io_failure_record(BTRFS_I(inode), ordered_extent->file_offset, ordered_extent->file_offset + ordered_extent->len - 1); if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) { truncated = true; logical_len = ordered_extent->truncated_len; /* Truncated the entire extent, don't bother adding */ if (!logical_len) goto out; } if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */ /* * For mwrite(mmap + memset to write) case, we still reserve * space for NOCOW range. * As NOCOW won't cause a new delayed ref, just free the space */ btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset, ordered_extent->len); btrfs_ordered_update_i_size(inode, 0, ordered_extent); if (nolock) trans = btrfs_join_transaction_nolock(root); else trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; goto out; } trans->block_rsv = &BTRFS_I(inode)->block_rsv; ret = btrfs_update_inode_fallback(trans, root, inode); if (ret) /* -ENOMEM or corruption */ btrfs_abort_transaction(trans, ret); goto out; } range_locked = true; lock_extent_bits(io_tree, ordered_extent->file_offset, ordered_extent->file_offset + ordered_extent->len - 1, &cached_state); ret = test_range_bit(io_tree, ordered_extent->file_offset, ordered_extent->file_offset + ordered_extent->len - 1, EXTENT_DEFRAG, 0, cached_state); if (ret) { u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item); if (0 && last_snapshot >= BTRFS_I(inode)->generation) /* the inode is shared */ new = record_old_file_extents(inode, ordered_extent); clear_extent_bit(io_tree, ordered_extent->file_offset, ordered_extent->file_offset + ordered_extent->len - 1, EXTENT_DEFRAG, 0, 0, &cached_state); } if (nolock) trans = btrfs_join_transaction_nolock(root); else trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; goto out; } trans->block_rsv = &BTRFS_I(inode)->block_rsv; if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) compress_type = ordered_extent->compress_type; if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { BUG_ON(compress_type); btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset, ordered_extent->len); ret = btrfs_mark_extent_written(trans, BTRFS_I(inode), ordered_extent->file_offset, ordered_extent->file_offset + logical_len); } else { BUG_ON(root == fs_info->tree_root); ret = insert_reserved_file_extent(trans, inode, ordered_extent->file_offset, ordered_extent->start, ordered_extent->disk_len, logical_len, logical_len, compress_type, 0, 0, BTRFS_FILE_EXTENT_REG); if (!ret) { clear_reserved_extent = false; btrfs_release_delalloc_bytes(fs_info, ordered_extent->start, ordered_extent->disk_len); } } unpin_extent_cache(&BTRFS_I(inode)->extent_tree, ordered_extent->file_offset, ordered_extent->len, trans->transid); if (ret < 0) { btrfs_abort_transaction(trans, ret); goto out; } ret = add_pending_csums(trans, inode, &ordered_extent->list); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } btrfs_ordered_update_i_size(inode, 0, ordered_extent); ret = btrfs_update_inode_fallback(trans, root, inode); if (ret) { /* -ENOMEM or corruption */ btrfs_abort_transaction(trans, ret); goto out; } ret = 0; out: if (range_locked || clear_new_delalloc_bytes) { unsigned int clear_bits = 0; if (range_locked) clear_bits |= EXTENT_LOCKED; if (clear_new_delalloc_bytes) clear_bits |= EXTENT_DELALLOC_NEW; clear_extent_bit(&BTRFS_I(inode)->io_tree, ordered_extent->file_offset, ordered_extent->file_offset + ordered_extent->len - 1, clear_bits, (clear_bits & EXTENT_LOCKED) ? 1 : 0, 0, &cached_state); } if (trans) btrfs_end_transaction(trans); if (ret || truncated) { u64 start, end; if (truncated) start = ordered_extent->file_offset + logical_len; else start = ordered_extent->file_offset; end = ordered_extent->file_offset + ordered_extent->len - 1; clear_extent_uptodate(io_tree, start, end, NULL); /* Drop the cache for the part of the extent we didn't write. */ btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0); /* * If the ordered extent had an IOERR or something else went * wrong we need to return the space for this ordered extent * back to the allocator. We only free the extent in the * truncated case if we didn't write out the extent at all. * * If we made it past insert_reserved_file_extent before we * errored out then we don't need to do this as the accounting * has already been done. */ if ((ret || !logical_len) && clear_reserved_extent && !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) btrfs_free_reserved_extent(fs_info, ordered_extent->start, ordered_extent->disk_len, 1); } /* * This needs to be done to make sure anybody waiting knows we are done * updating everything for this ordered extent. */ btrfs_remove_ordered_extent(inode, ordered_extent); /* for snapshot-aware defrag */ if (new) { if (ret) { free_sa_defrag_extent(new); atomic_dec(&fs_info->defrag_running); } else { relink_file_extents(new); } } /* once for us */ btrfs_put_ordered_extent(ordered_extent); /* once for the tree */ btrfs_put_ordered_extent(ordered_extent); return ret; } static void finish_ordered_fn(struct btrfs_work *work) { struct btrfs_ordered_extent *ordered_extent; ordered_extent = container_of(work, struct btrfs_ordered_extent, work); btrfs_finish_ordered_io(ordered_extent); } void btrfs_writepage_endio_finish_ordered(struct page *page, u64 start, u64 end, int uptodate) { struct inode *inode = page->mapping->host; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_ordered_extent *ordered_extent = NULL; struct btrfs_workqueue *wq; btrfs_work_func_t func; trace_btrfs_writepage_end_io_hook(page, start, end, uptodate); ClearPagePrivate2(page); if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start, end - start + 1, uptodate)) return; if (btrfs_is_free_space_inode(BTRFS_I(inode))) { wq = fs_info->endio_freespace_worker; func = btrfs_freespace_write_helper; } else { wq = fs_info->endio_write_workers; func = btrfs_endio_write_helper; } btrfs_init_work(&ordered_extent->work, func, finish_ordered_fn, NULL, NULL); btrfs_queue_work(wq, &ordered_extent->work); } static int __readpage_endio_check(struct inode *inode, struct btrfs_io_bio *io_bio, int icsum, struct page *page, int pgoff, u64 start, size_t len) { char *kaddr; u32 csum_expected; u32 csum = ~(u32)0; csum_expected = *(((u32 *)io_bio->csum) + icsum); kaddr = kmap_atomic(page); csum = btrfs_csum_data(kaddr + pgoff, csum, len); btrfs_csum_final(csum, (u8 *)&csum); if (csum != csum_expected) goto zeroit; kunmap_atomic(kaddr); return 0; zeroit: btrfs_print_data_csum_error(BTRFS_I(inode), start, csum, csum_expected, io_bio->mirror_num); memset(kaddr + pgoff, 1, len); flush_dcache_page(page); kunmap_atomic(kaddr); return -EIO; } /* * when reads are done, we need to check csums to verify the data is correct * if there's a match, we allow the bio to finish. If not, the code in * extent_io.c will try to find good copies for us. */ static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio, u64 phy_offset, struct page *page, u64 start, u64 end, int mirror) { size_t offset = start - page_offset(page); struct inode *inode = page->mapping->host; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_root *root = BTRFS_I(inode)->root; if (PageChecked(page)) { ClearPageChecked(page); return 0; } if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) return 0; if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID && test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) { clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM); return 0; } phy_offset >>= inode->i_sb->s_blocksize_bits; return __readpage_endio_check(inode, io_bio, phy_offset, page, offset, start, (size_t)(end - start + 1)); } /* * btrfs_add_delayed_iput - perform a delayed iput on @inode * * @inode: The inode we want to perform iput on * * This function uses the generic vfs_inode::i_count to track whether we should * just decrement it (in case it's > 1) or if this is the last iput then link * the inode to the delayed iput machinery. Delayed iputs are processed at * transaction commit time/superblock commit/cleaner kthread. */ void btrfs_add_delayed_iput(struct inode *inode) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_inode *binode = BTRFS_I(inode); if (atomic_add_unless(&inode->i_count, -1, 1)) return; spin_lock(&fs_info->delayed_iput_lock); ASSERT(list_empty(&binode->delayed_iput)); list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs); spin_unlock(&fs_info->delayed_iput_lock); } void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info) { spin_lock(&fs_info->delayed_iput_lock); while (!list_empty(&fs_info->delayed_iputs)) { struct btrfs_inode *inode; inode = list_first_entry(&fs_info->delayed_iputs, struct btrfs_inode, delayed_iput); list_del_init(&inode->delayed_iput); spin_unlock(&fs_info->delayed_iput_lock); iput(&inode->vfs_inode); spin_lock(&fs_info->delayed_iput_lock); } spin_unlock(&fs_info->delayed_iput_lock); } /* * This creates an orphan entry for the given inode in case something goes wrong * in the middle of an unlink. */ int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct btrfs_inode *inode) { int ret; ret = btrfs_insert_orphan_item(trans, inode->root, btrfs_ino(inode)); if (ret && ret != -EEXIST) { btrfs_abort_transaction(trans, ret); return ret; } return 0; } /* * We have done the delete so we can go ahead and remove the orphan item for * this particular inode. */ static int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct btrfs_inode *inode) { return btrfs_del_orphan_item(trans, inode->root, btrfs_ino(inode)); } /* * this cleans up any orphans that may be left on the list from the last use * of this root. */ int btrfs_orphan_cleanup(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key, found_key; struct btrfs_trans_handle *trans; struct inode *inode; u64 last_objectid = 0; int ret = 0, nr_unlink = 0; if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED)) return 0; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } path->reada = READA_BACK; key.objectid = BTRFS_ORPHAN_OBJECTID; key.type = BTRFS_ORPHAN_ITEM_KEY; key.offset = (u64)-1; while (1) { ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; /* * if ret == 0 means we found what we were searching for, which * is weird, but possible, so only screw with path if we didn't * find the key and see if we have stuff that matches */ if (ret > 0) { ret = 0; if (path->slots[0] == 0) break; path->slots[0]--; } /* pull out the item */ leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); /* make sure the item matches what we want */ if (found_key.objectid != BTRFS_ORPHAN_OBJECTID) break; if (found_key.type != BTRFS_ORPHAN_ITEM_KEY) break; /* release the path since we're done with it */ btrfs_release_path(path); /* * this is where we are basically btrfs_lookup, without the * crossing root thing. we store the inode number in the * offset of the orphan item. */ if (found_key.offset == last_objectid) { btrfs_err(fs_info, "Error removing orphan entry, stopping orphan cleanup"); ret = -EINVAL; goto out; } last_objectid = found_key.offset; found_key.objectid = found_key.offset; found_key.type = BTRFS_INODE_ITEM_KEY; found_key.offset = 0; inode = btrfs_iget(fs_info->sb, &found_key, root, NULL); ret = PTR_ERR_OR_ZERO(inode); if (ret && ret != -ENOENT) goto out; if (ret == -ENOENT && root == fs_info->tree_root) { struct btrfs_root *dead_root; struct btrfs_fs_info *fs_info = root->fs_info; int is_dead_root = 0; /* * this is an orphan in the tree root. Currently these * could come from 2 sources: * a) a snapshot deletion in progress * b) a free space cache inode * We need to distinguish those two, as the snapshot * orphan must not get deleted. * find_dead_roots already ran before us, so if this * is a snapshot deletion, we should find the root * in the dead_roots list */ spin_lock(&fs_info->trans_lock); list_for_each_entry(dead_root, &fs_info->dead_roots, root_list) { if (dead_root->root_key.objectid == found_key.objectid) { is_dead_root = 1; break; } } spin_unlock(&fs_info->trans_lock); if (is_dead_root) { /* prevent this orphan from being found again */ key.offset = found_key.objectid - 1; continue; } } /* * If we have an inode with links, there are a couple of * possibilities. Old kernels (before v3.12) used to create an * orphan item for truncate indicating that there were possibly * extent items past i_size that needed to be deleted. In v3.12, * truncate was changed to update i_size in sync with the extent * items, but the (useless) orphan item was still created. Since * v4.18, we don't create the orphan item for truncate at all. * * So, this item could mean that we need to do a truncate, but * only if this filesystem was last used on a pre-v3.12 kernel * and was not cleanly unmounted. The odds of that are quite * slim, and it's a pain to do the truncate now, so just delete * the orphan item. * * It's also possible that this orphan item was supposed to be * deleted but wasn't. The inode number may have been reused, * but either way, we can delete the orphan item. */ if (ret == -ENOENT || inode->i_nlink) { if (!ret) iput(inode); trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } btrfs_debug(fs_info, "auto deleting %Lu", found_key.objectid); ret = btrfs_del_orphan_item(trans, root, found_key.objectid); btrfs_end_transaction(trans); if (ret) goto out; continue; } nr_unlink++; /* this will do delete_inode and everything for us */ iput(inode); } /* release the path since we're done with it */ btrfs_release_path(path); root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE; if (test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)) { trans = btrfs_join_transaction(root); if (!IS_ERR(trans)) btrfs_end_transaction(trans); } if (nr_unlink) btrfs_debug(fs_info, "unlinked %d orphans", nr_unlink); out: if (ret) btrfs_err(fs_info, "could not do orphan cleanup %d", ret); btrfs_free_path(path); return ret; } /* * very simple check to peek ahead in the leaf looking for xattrs. If we * don't find any xattrs, we know there can't be any acls. * * slot is the slot the inode is in, objectid is the objectid of the inode */ static noinline int acls_after_inode_item(struct extent_buffer *leaf, int slot, u64 objectid, int *first_xattr_slot) { u32 nritems = btrfs_header_nritems(leaf); struct btrfs_key found_key; static u64 xattr_access = 0; static u64 xattr_default = 0; int scanned = 0; if (!xattr_access) { xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS, strlen(XATTR_NAME_POSIX_ACL_ACCESS)); xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT, strlen(XATTR_NAME_POSIX_ACL_DEFAULT)); } slot++; *first_xattr_slot = -1; while (slot < nritems) { btrfs_item_key_to_cpu(leaf, &found_key, slot); /* we found a different objectid, there must not be acls */ if (found_key.objectid != objectid) return 0; /* we found an xattr, assume we've got an acl */ if (found_key.type == BTRFS_XATTR_ITEM_KEY) { if (*first_xattr_slot == -1) *first_xattr_slot = slot; if (found_key.offset == xattr_access || found_key.offset == xattr_default) return 1; } /* * we found a key greater than an xattr key, there can't * be any acls later on */ if (found_key.type > BTRFS_XATTR_ITEM_KEY) return 0; slot++; scanned++; /* * it goes inode, inode backrefs, xattrs, extents, * so if there are a ton of hard links to an inode there can * be a lot of backrefs. Don't waste time searching too hard, * this is just an optimization */ if (scanned >= 8) break; } /* we hit the end of the leaf before we found an xattr or * something larger than an xattr. We have to assume the inode * has acls */ if (*first_xattr_slot == -1) *first_xattr_slot = slot; return 1; } /* * read an inode from the btree into the in-memory inode */ static int btrfs_read_locked_inode(struct inode *inode, struct btrfs_path *in_path) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_path *path = in_path; struct extent_buffer *leaf; struct btrfs_inode_item *inode_item; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_key location; unsigned long ptr; int maybe_acls; u32 rdev; int ret; bool filled = false; int first_xattr_slot; ret = btrfs_fill_inode(inode, &rdev); if (!ret) filled = true; if (!path) { path = btrfs_alloc_path(); if (!path) return -ENOMEM; } memcpy(&location, &BTRFS_I(inode)->location, sizeof(location)); ret = btrfs_lookup_inode(NULL, root, path, &location, 0); if (ret) { if (path != in_path) btrfs_free_path(path); return ret; } leaf = path->nodes[0]; if (filled) goto cache_index; inode_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); inode->i_mode = btrfs_inode_mode(leaf, inode_item); set_nlink(inode, btrfs_inode_nlink(leaf, inode_item)); i_uid_write(inode, btrfs_inode_uid(leaf, inode_item)); i_gid_write(inode, btrfs_inode_gid(leaf, inode_item)); btrfs_i_size_write(BTRFS_I(inode), btrfs_inode_size(leaf, inode_item)); inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->atime); inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->atime); inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->mtime); inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->mtime); inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->ctime); inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->ctime); BTRFS_I(inode)->i_otime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->otime); BTRFS_I(inode)->i_otime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->otime); inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item)); BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item); BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item); inode_set_iversion_queried(inode, btrfs_inode_sequence(leaf, inode_item)); inode->i_generation = BTRFS_I(inode)->generation; inode->i_rdev = 0; rdev = btrfs_inode_rdev(leaf, inode_item); BTRFS_I(inode)->index_cnt = (u64)-1; BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item); cache_index: /* * If we were modified in the current generation and evicted from memory * and then re-read we need to do a full sync since we don't have any * idea about which extents were modified before we were evicted from * cache. * * This is required for both inode re-read from disk and delayed inode * in delayed_nodes_tree. */ if (BTRFS_I(inode)->last_trans == fs_info->generation) set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); /* * We don't persist the id of the transaction where an unlink operation * against the inode was last made. So here we assume the inode might * have been evicted, and therefore the exact value of last_unlink_trans * lost, and set it to last_trans to avoid metadata inconsistencies * between the inode and its parent if the inode is fsync'ed and the log * replayed. For example, in the scenario: * * touch mydir/foo * ln mydir/foo mydir/bar * sync * unlink mydir/bar * echo 2 > /proc/sys/vm/drop_caches # evicts inode * xfs_io -c fsync mydir/foo * * mount fs, triggers fsync log replay * * We must make sure that when we fsync our inode foo we also log its * parent inode, otherwise after log replay the parent still has the * dentry with the "bar" name but our inode foo has a link count of 1 * and doesn't have an inode ref with the name "bar" anymore. * * Setting last_unlink_trans to last_trans is a pessimistic approach, * but it guarantees correctness at the expense of occasional full * transaction commits on fsync if our inode is a directory, or if our * inode is not a directory, logging its parent unnecessarily. */ BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans; /* * Similar reasoning for last_link_trans, needs to be set otherwise * for a case like the following: * * mkdir A * touch foo * ln foo A/bar * echo 2 > /proc/sys/vm/drop_caches * fsync foo * * * Would result in link bar and directory A not existing after the power * failure. */ BTRFS_I(inode)->last_link_trans = BTRFS_I(inode)->last_trans; path->slots[0]++; if (inode->i_nlink != 1 || path->slots[0] >= btrfs_header_nritems(leaf)) goto cache_acl; btrfs_item_key_to_cpu(leaf, &location, path->slots[0]); if (location.objectid != btrfs_ino(BTRFS_I(inode))) goto cache_acl; ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); if (location.type == BTRFS_INODE_REF_KEY) { struct btrfs_inode_ref *ref; ref = (struct btrfs_inode_ref *)ptr; BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref); } else if (location.type == BTRFS_INODE_EXTREF_KEY) { struct btrfs_inode_extref *extref; extref = (struct btrfs_inode_extref *)ptr; BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf, extref); } cache_acl: /* * try to precache a NULL acl entry for files that don't have * any xattrs or acls */ maybe_acls = acls_after_inode_item(leaf, path->slots[0], btrfs_ino(BTRFS_I(inode)), &first_xattr_slot); if (first_xattr_slot != -1) { path->slots[0] = first_xattr_slot; ret = btrfs_load_inode_props(inode, path); if (ret) btrfs_err(fs_info, "error loading props for ino %llu (root %llu): %d", btrfs_ino(BTRFS_I(inode)), root->root_key.objectid, ret); } if (path != in_path) btrfs_free_path(path); if (!maybe_acls) cache_no_acl(inode); switch (inode->i_mode & S_IFMT) { case S_IFREG: inode->i_mapping->a_ops = &btrfs_aops; BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; break; case S_IFDIR: inode->i_fop = &btrfs_dir_file_operations; inode->i_op = &btrfs_dir_inode_operations; break; case S_IFLNK: inode->i_op = &btrfs_symlink_inode_operations; inode_nohighmem(inode); inode->i_mapping->a_ops = &btrfs_aops; break; default: inode->i_op = &btrfs_special_inode_operations; init_special_inode(inode, inode->i_mode, rdev); break; } btrfs_sync_inode_flags_to_i_flags(inode); return 0; } /* * given a leaf and an inode, copy the inode fields into the leaf */ static void fill_inode_item(struct btrfs_trans_handle *trans, struct extent_buffer *leaf, struct btrfs_inode_item *item, struct inode *inode) { struct btrfs_map_token token; btrfs_init_map_token(&token); btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token); btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token); btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size, &token); btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token); btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token); btrfs_set_token_timespec_sec(leaf, &item->atime, inode->i_atime.tv_sec, &token); btrfs_set_token_timespec_nsec(leaf, &item->atime, inode->i_atime.tv_nsec, &token); btrfs_set_token_timespec_sec(leaf, &item->mtime, inode->i_mtime.tv_sec, &token); btrfs_set_token_timespec_nsec(leaf, &item->mtime, inode->i_mtime.tv_nsec, &token); btrfs_set_token_timespec_sec(leaf, &item->ctime, inode->i_ctime.tv_sec, &token); btrfs_set_token_timespec_nsec(leaf, &item->ctime, inode->i_ctime.tv_nsec, &token); btrfs_set_token_timespec_sec(leaf, &item->otime, BTRFS_I(inode)->i_otime.tv_sec, &token); btrfs_set_token_timespec_nsec(leaf, &item->otime, BTRFS_I(inode)->i_otime.tv_nsec, &token); btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode), &token); btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation, &token); btrfs_set_token_inode_sequence(leaf, item, inode_peek_iversion(inode), &token); btrfs_set_token_inode_transid(leaf, item, trans->transid, &token); btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token); btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token); btrfs_set_token_inode_block_group(leaf, item, 0, &token); } /* * copy everything in the in-memory inode into the btree. */ static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode) { struct btrfs_inode_item *inode_item; struct btrfs_path *path; struct extent_buffer *leaf; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->leave_spinning = 1; ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location, 1); if (ret) { if (ret > 0) ret = -ENOENT; goto failed; } leaf = path->nodes[0]; inode_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); fill_inode_item(trans, leaf, inode_item, inode); btrfs_mark_buffer_dirty(leaf); btrfs_set_inode_last_trans(trans, inode); ret = 0; failed: btrfs_free_path(path); return ret; } /* * copy everything in the in-memory inode into the btree. */ noinline int btrfs_update_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode) { struct btrfs_fs_info *fs_info = root->fs_info; int ret; /* * If the inode is a free space inode, we can deadlock during commit * if we put it into the delayed code. * * The data relocation inode should also be directly updated * without delay */ if (!btrfs_is_free_space_inode(BTRFS_I(inode)) && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID && !test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) { btrfs_update_root_times(trans, root); ret = btrfs_delayed_update_inode(trans, root, inode); if (!ret) btrfs_set_inode_last_trans(trans, inode); return ret; } return btrfs_update_inode_item(trans, root, inode); } noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode) { int ret; ret = btrfs_update_inode(trans, root, inode); if (ret == -ENOSPC) return btrfs_update_inode_item(trans, root, inode); return ret; } /* * unlink helper that gets used here in inode.c and in the tree logging * recovery code. It remove a link in a directory with a given name, and * also drops the back refs in the inode to the directory */ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_inode *dir, struct btrfs_inode *inode, const char *name, int name_len) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_path *path; int ret = 0; struct extent_buffer *leaf; struct btrfs_dir_item *di; struct btrfs_key key; u64 index; u64 ino = btrfs_ino(inode); u64 dir_ino = btrfs_ino(dir); path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } path->leave_spinning = 1; di = btrfs_lookup_dir_item(trans, root, path, dir_ino, name, name_len, -1); if (IS_ERR_OR_NULL(di)) { ret = di ? PTR_ERR(di) : -ENOENT; goto err; } leaf = path->nodes[0]; btrfs_dir_item_key_to_cpu(leaf, di, &key); ret = btrfs_delete_one_dir_name(trans, root, path, di); if (ret) goto err; btrfs_release_path(path); /* * If we don't have dir index, we have to get it by looking up * the inode ref, since we get the inode ref, remove it directly, * it is unnecessary to do delayed deletion. * * But if we have dir index, needn't search inode ref to get it. * Since the inode ref is close to the inode item, it is better * that we delay to delete it, and just do this deletion when * we update the inode item. */ if (inode->dir_index) { ret = btrfs_delayed_delete_inode_ref(inode); if (!ret) { index = inode->dir_index; goto skip_backref; } } ret = btrfs_del_inode_ref(trans, root, name, name_len, ino, dir_ino, &index); if (ret) { btrfs_info(fs_info, "failed to delete reference to %.*s, inode %llu parent %llu", name_len, name, ino, dir_ino); btrfs_abort_transaction(trans, ret); goto err; } skip_backref: ret = btrfs_delete_delayed_dir_index(trans, dir, index); if (ret) { btrfs_abort_transaction(trans, ret); goto err; } ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, inode, dir_ino); if (ret != 0 && ret != -ENOENT) { btrfs_abort_transaction(trans, ret); goto err; } ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, dir, index); if (ret == -ENOENT) ret = 0; else if (ret) btrfs_abort_transaction(trans, ret); err: btrfs_free_path(path); if (ret) goto out; btrfs_i_size_write(dir, dir->vfs_inode.i_size - name_len * 2); inode_inc_iversion(&inode->vfs_inode); inode_inc_iversion(&dir->vfs_inode); inode->vfs_inode.i_ctime = dir->vfs_inode.i_mtime = dir->vfs_inode.i_ctime = current_time(&inode->vfs_inode); ret = btrfs_update_inode(trans, root, &dir->vfs_inode); out: return ret; } int btrfs_unlink_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_inode *dir, struct btrfs_inode *inode, const char *name, int name_len) { int ret; ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len); if (!ret) { drop_nlink(&inode->vfs_inode); ret = btrfs_update_inode(trans, root, &inode->vfs_inode); } return ret; } /* * helper to start transaction for unlink and rmdir. * * unlink and rmdir are special in btrfs, they do not always free space, so * if we cannot make our reservations the normal way try and see if there is * plenty of slack room in the global reserve to migrate, otherwise we cannot * allow the unlink to occur. */ static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir) { struct btrfs_root *root = BTRFS_I(dir)->root; /* * 1 for the possible orphan item * 1 for the dir item * 1 for the dir index * 1 for the inode ref * 1 for the inode */ return btrfs_start_transaction_fallback_global_rsv(root, 5, 5); } static int btrfs_unlink(struct inode *dir, struct dentry *dentry) { struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_trans_handle *trans; struct inode *inode = d_inode(dentry); int ret; trans = __unlink_start_trans(dir); if (IS_ERR(trans)) return PTR_ERR(trans); btrfs_record_unlink_dir(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)), 0); ret = btrfs_unlink_inode(trans, root, BTRFS_I(dir), BTRFS_I(d_inode(dentry)), dentry->d_name.name, dentry->d_name.len); if (ret) goto out; if (inode->i_nlink == 0) { ret = btrfs_orphan_add(trans, BTRFS_I(inode)); if (ret) goto out; } out: btrfs_end_transaction(trans); btrfs_btree_balance_dirty(root->fs_info); return ret; } static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, struct inode *dir, u64 objectid, const char *name, int name_len) { struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_dir_item *di; struct btrfs_key key; u64 index; int ret; u64 dir_ino = btrfs_ino(BTRFS_I(dir)); path = btrfs_alloc_path(); if (!path) return -ENOMEM; di = btrfs_lookup_dir_item(trans, root, path, dir_ino, name, name_len, -1); if (IS_ERR_OR_NULL(di)) { ret = di ? PTR_ERR(di) : -ENOENT; goto out; } leaf = path->nodes[0]; btrfs_dir_item_key_to_cpu(leaf, di, &key); WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); ret = btrfs_delete_one_dir_name(trans, root, path, di); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } btrfs_release_path(path); ret = btrfs_del_root_ref(trans, objectid, root->root_key.objectid, dir_ino, &index, name, name_len); if (ret < 0) { if (ret != -ENOENT) { btrfs_abort_transaction(trans, ret); goto out; } di = btrfs_search_dir_index_item(root, path, dir_ino, name, name_len); if (IS_ERR_OR_NULL(di)) { if (!di) ret = -ENOENT; else ret = PTR_ERR(di); btrfs_abort_transaction(trans, ret); goto out; } leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); index = key.offset; } btrfs_release_path(path); ret = btrfs_delete_delayed_dir_index(trans, BTRFS_I(dir), index); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } btrfs_i_size_write(BTRFS_I(dir), dir->i_size - name_len * 2); inode_inc_iversion(dir); dir->i_mtime = dir->i_ctime = current_time(dir); ret = btrfs_update_inode_fallback(trans, root, dir); if (ret) btrfs_abort_transaction(trans, ret); out: btrfs_free_path(path); return ret; } /* * Helper to check if the subvolume references other subvolumes or if it's * default. */ static noinline int may_destroy_subvol(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_path *path; struct btrfs_dir_item *di; struct btrfs_key key; u64 dir_id; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; /* Make sure this root isn't set as the default subvol */ dir_id = btrfs_super_root_dir(fs_info->super_copy); di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path, dir_id, "default", 7, 0); if (di && !IS_ERR(di)) { btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key); if (key.objectid == root->root_key.objectid) { ret = -EPERM; btrfs_err(fs_info, "deleting default subvolume %llu is not allowed", key.objectid); goto out; } btrfs_release_path(path); } key.objectid = root->root_key.objectid; key.type = BTRFS_ROOT_REF_KEY; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); if (ret < 0) goto out; BUG_ON(ret == 0); ret = 0; if (path->slots[0] > 0) { path->slots[0]--; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); if (key.objectid == root->root_key.objectid && key.type == BTRFS_ROOT_REF_KEY) ret = -ENOTEMPTY; } out: btrfs_free_path(path); return ret; } /* Delete all dentries for inodes belonging to the root */ static void btrfs_prune_dentries(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; struct rb_node *node; struct rb_node *prev; struct btrfs_inode *entry; struct inode *inode; u64 objectid = 0; if (!test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) WARN_ON(btrfs_root_refs(&root->root_item) != 0); spin_lock(&root->inode_lock); again: node = root->inode_tree.rb_node; prev = NULL; while (node) { prev = node; entry = rb_entry(node, struct btrfs_inode, rb_node); if (objectid < btrfs_ino(entry)) node = node->rb_left; else if (objectid > btrfs_ino(entry)) node = node->rb_right; else break; } if (!node) { while (prev) { entry = rb_entry(prev, struct btrfs_inode, rb_node); if (objectid <= btrfs_ino(entry)) { node = prev; break; } prev = rb_next(prev); } } while (node) { entry = rb_entry(node, struct btrfs_inode, rb_node); objectid = btrfs_ino(entry) + 1; inode = igrab(&entry->vfs_inode); if (inode) { spin_unlock(&root->inode_lock); if (atomic_read(&inode->i_count) > 1) d_prune_aliases(inode); /* * btrfs_drop_inode will have it removed from the inode * cache when its usage count hits zero. */ iput(inode); cond_resched(); spin_lock(&root->inode_lock); goto again; } if (cond_resched_lock(&root->inode_lock)) goto again; node = rb_next(node); } spin_unlock(&root->inode_lock); } int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry) { struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb); struct btrfs_root *root = BTRFS_I(dir)->root; struct inode *inode = d_inode(dentry); struct btrfs_root *dest = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; struct btrfs_block_rsv block_rsv; u64 root_flags; int ret; int err; /* * Don't allow to delete a subvolume with send in progress. This is * inside the inode lock so the error handling that has to drop the bit * again is not run concurrently. */ spin_lock(&dest->root_item_lock); if (dest->send_in_progress) { spin_unlock(&dest->root_item_lock); btrfs_warn(fs_info, "attempt to delete subvolume %llu during send", dest->root_key.objectid); return -EPERM; } root_flags = btrfs_root_flags(&dest->root_item); btrfs_set_root_flags(&dest->root_item, root_flags | BTRFS_ROOT_SUBVOL_DEAD); spin_unlock(&dest->root_item_lock); down_write(&fs_info->subvol_sem); err = may_destroy_subvol(dest); if (err) goto out_up_write; btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); /* * One for dir inode, * two for dir entries, * two for root ref/backref. */ err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 5, true); if (err) goto out_up_write; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { err = PTR_ERR(trans); goto out_release; } trans->block_rsv = &block_rsv; trans->bytes_reserved = block_rsv.size; btrfs_record_snapshot_destroy(trans, BTRFS_I(dir)); ret = btrfs_unlink_subvol(trans, dir, dest->root_key.objectid, dentry->d_name.name, dentry->d_name.len); if (ret) { err = ret; btrfs_abort_transaction(trans, ret); goto out_end_trans; } btrfs_record_root_in_trans(trans, dest); memset(&dest->root_item.drop_progress, 0, sizeof(dest->root_item.drop_progress)); dest->root_item.drop_level = 0; btrfs_set_root_refs(&dest->root_item, 0); if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) { ret = btrfs_insert_orphan_item(trans, fs_info->tree_root, dest->root_key.objectid); if (ret) { btrfs_abort_transaction(trans, ret); err = ret; goto out_end_trans; } } ret = btrfs_uuid_tree_remove(trans, dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL, dest->root_key.objectid); if (ret && ret != -ENOENT) { btrfs_abort_transaction(trans, ret); err = ret; goto out_end_trans; } if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) { ret = btrfs_uuid_tree_remove(trans, dest->root_item.received_uuid, BTRFS_UUID_KEY_RECEIVED_SUBVOL, dest->root_key.objectid); if (ret && ret != -ENOENT) { btrfs_abort_transaction(trans, ret); err = ret; goto out_end_trans; } } out_end_trans: trans->block_rsv = NULL; trans->bytes_reserved = 0; ret = btrfs_end_transaction(trans); if (ret && !err) err = ret; inode->i_flags |= S_DEAD; out_release: btrfs_subvolume_release_metadata(fs_info, &block_rsv); out_up_write: up_write(&fs_info->subvol_sem); if (err) { spin_lock(&dest->root_item_lock); root_flags = btrfs_root_flags(&dest->root_item); btrfs_set_root_flags(&dest->root_item, root_flags & ~BTRFS_ROOT_SUBVOL_DEAD); spin_unlock(&dest->root_item_lock); } else { d_invalidate(dentry); btrfs_prune_dentries(dest); ASSERT(dest->send_in_progress == 0); /* the last ref */ if (dest->ino_cache_inode) { iput(dest->ino_cache_inode); dest->ino_cache_inode = NULL; } } return err; } static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) { struct inode *inode = d_inode(dentry); int err = 0; struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_trans_handle *trans; u64 last_unlink_trans; if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) return -ENOTEMPTY; if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID) return btrfs_delete_subvolume(dir, dentry); trans = __unlink_start_trans(dir); if (IS_ERR(trans)) return PTR_ERR(trans); if (unlikely(btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { err = btrfs_unlink_subvol(trans, dir, BTRFS_I(inode)->location.objectid, dentry->d_name.name, dentry->d_name.len); goto out; } err = btrfs_orphan_add(trans, BTRFS_I(inode)); if (err) goto out; last_unlink_trans = BTRFS_I(inode)->last_unlink_trans; /* now the directory is empty */ err = btrfs_unlink_inode(trans, root, BTRFS_I(dir), BTRFS_I(d_inode(dentry)), dentry->d_name.name, dentry->d_name.len); if (!err) { btrfs_i_size_write(BTRFS_I(inode), 0); /* * Propagate the last_unlink_trans value of the deleted dir to * its parent directory. This is to prevent an unrecoverable * log tree in the case we do something like this: * 1) create dir foo * 2) create snapshot under dir foo * 3) delete the snapshot * 4) rmdir foo * 5) mkdir foo * 6) fsync foo or some file inside foo */ if (last_unlink_trans >= trans->transid) BTRFS_I(dir)->last_unlink_trans = last_unlink_trans; } out: btrfs_end_transaction(trans); btrfs_btree_balance_dirty(root->fs_info); return err; } /* * Return this if we need to call truncate_block for the last bit of the * truncate. */ #define NEED_TRUNCATE_BLOCK 1 /* * this can truncate away extent items, csum items and directory items. * It starts at a high offset and removes keys until it can't find * any higher than new_size * * csum items that cross the new i_size are truncated to the new size * as well. * * min_type is the minimum key type to truncate down to. If set to 0, this * will kill all the items on this inode, including the INODE_ITEM_KEY. */ int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 new_size, u32 min_type) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_file_extent_item *fi; struct btrfs_key key; struct btrfs_key found_key; u64 extent_start = 0; u64 extent_num_bytes = 0; u64 extent_offset = 0; u64 item_end = 0; u64 last_size = new_size; u32 found_type = (u8)-1; int found_extent; int del_item; int pending_del_nr = 0; int pending_del_slot = 0; int extent_type = -1; int ret; u64 ino = btrfs_ino(BTRFS_I(inode)); u64 bytes_deleted = 0; bool be_nice = false; bool should_throttle = false; BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY); /* * for non-free space inodes and ref cows, we want to back off from * time to time */ if (!btrfs_is_free_space_inode(BTRFS_I(inode)) && test_bit(BTRFS_ROOT_REF_COWS, &root->state)) be_nice = true; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = READA_BACK; /* * We want to drop from the next block forward in case this new size is * not block aligned since we will be keeping the last block of the * extent just the way it is. */ if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || root == fs_info->tree_root) btrfs_drop_extent_cache(BTRFS_I(inode), ALIGN(new_size, fs_info->sectorsize), (u64)-1, 0); /* * This function is also used to drop the items in the log tree before * we relog the inode, so if root != BTRFS_I(inode)->root, it means * it is used to drop the logged items. So we shouldn't kill the delayed * items. */ if (min_type == 0 && root == BTRFS_I(inode)->root) btrfs_kill_delayed_inode_items(BTRFS_I(inode)); key.objectid = ino; key.offset = (u64)-1; key.type = (u8)-1; search_again: /* * with a 16K leaf size and 128MB extents, you can actually queue * up a huge file in a single leaf. Most of the time that * bytes_deleted is > 0, it will be huge by the time we get here */ if (be_nice && bytes_deleted > SZ_32M && btrfs_should_end_transaction(trans)) { ret = -EAGAIN; goto out; } path->leave_spinning = 1; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0) { ret = 0; /* there are no items in the tree for us to truncate, we're * done */ if (path->slots[0] == 0) goto out; path->slots[0]--; } while (1) { fi = NULL; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); found_type = found_key.type; if (found_key.objectid != ino) break; if (found_type < min_type) break; item_end = found_key.offset; if (found_type == BTRFS_EXTENT_DATA_KEY) { fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); extent_type = btrfs_file_extent_type(leaf, fi); if (extent_type != BTRFS_FILE_EXTENT_INLINE) { item_end += btrfs_file_extent_num_bytes(leaf, fi); trace_btrfs_truncate_show_fi_regular( BTRFS_I(inode), leaf, fi, found_key.offset); } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { item_end += btrfs_file_extent_ram_bytes(leaf, fi); trace_btrfs_truncate_show_fi_inline( BTRFS_I(inode), leaf, fi, path->slots[0], found_key.offset); } item_end--; } if (found_type > min_type) { del_item = 1; } else { if (item_end < new_size) break; if (found_key.offset >= new_size) del_item = 1; else del_item = 0; } found_extent = 0; /* FIXME, shrink the extent if the ref count is only 1 */ if (found_type != BTRFS_EXTENT_DATA_KEY) goto delete; if (extent_type != BTRFS_FILE_EXTENT_INLINE) { u64 num_dec; extent_start = btrfs_file_extent_disk_bytenr(leaf, fi); if (!del_item) { u64 orig_num_bytes = btrfs_file_extent_num_bytes(leaf, fi); extent_num_bytes = ALIGN(new_size - found_key.offset, fs_info->sectorsize); btrfs_set_file_extent_num_bytes(leaf, fi, extent_num_bytes); num_dec = (orig_num_bytes - extent_num_bytes); if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) && extent_start != 0) inode_sub_bytes(inode, num_dec); btrfs_mark_buffer_dirty(leaf); } else { extent_num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); extent_offset = found_key.offset - btrfs_file_extent_offset(leaf, fi); /* FIXME blocksize != 4096 */ num_dec = btrfs_file_extent_num_bytes(leaf, fi); if (extent_start != 0) { found_extent = 1; if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) inode_sub_bytes(inode, num_dec); } } } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { /* * we can't truncate inline items that have had * special encodings */ if (!del_item && btrfs_file_extent_encryption(leaf, fi) == 0 && btrfs_file_extent_other_encoding(leaf, fi) == 0 && btrfs_file_extent_compression(leaf, fi) == 0) { u32 size = (u32)(new_size - found_key.offset); btrfs_set_file_extent_ram_bytes(leaf, fi, size); size = btrfs_file_extent_calc_inline_size(size); btrfs_truncate_item(root->fs_info, path, size, 1); } else if (!del_item) { /* * We have to bail so the last_size is set to * just before this extent. */ ret = NEED_TRUNCATE_BLOCK; break; } if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) inode_sub_bytes(inode, item_end + 1 - new_size); } delete: if (del_item) last_size = found_key.offset; else last_size = new_size; if (del_item) { if (!pending_del_nr) { /* no pending yet, add ourselves */ pending_del_slot = path->slots[0]; pending_del_nr = 1; } else if (pending_del_nr && path->slots[0] + 1 == pending_del_slot) { /* hop on the pending chunk */ pending_del_nr++; pending_del_slot = path->slots[0]; } else { BUG(); } } else { break; } should_throttle = false; if (found_extent && (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || root == fs_info->tree_root)) { btrfs_set_path_blocking(path); bytes_deleted += extent_num_bytes; ret = btrfs_free_extent(trans, root, extent_start, extent_num_bytes, 0, btrfs_header_owner(leaf), ino, extent_offset); if (ret) { btrfs_abort_transaction(trans, ret); break; } if (be_nice) { if (btrfs_should_throttle_delayed_refs(trans)) should_throttle = true; } } if (found_type == BTRFS_INODE_ITEM_KEY) break; if (path->slots[0] == 0 || path->slots[0] != pending_del_slot || should_throttle) { if (pending_del_nr) { ret = btrfs_del_items(trans, root, path, pending_del_slot, pending_del_nr); if (ret) { btrfs_abort_transaction(trans, ret); break; } pending_del_nr = 0; } btrfs_release_path(path); /* * We can generate a lot of delayed refs, so we need to * throttle every once and a while and make sure we're * adding enough space to keep up with the work we are * generating. Since we hold a transaction here we * can't flush, and we don't want to FLUSH_LIMIT because * we could have generated too many delayed refs to * actually allocate, so just bail if we're short and * let the normal reservation dance happen higher up. */ if (should_throttle) { ret = btrfs_delayed_refs_rsv_refill(fs_info, BTRFS_RESERVE_NO_FLUSH); if (ret) { ret = -EAGAIN; break; } } goto search_again; } else { path->slots[0]--; } } out: if (ret >= 0 && pending_del_nr) { int err; err = btrfs_del_items(trans, root, path, pending_del_slot, pending_del_nr); if (err) { btrfs_abort_transaction(trans, err); ret = err; } } if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { ASSERT(last_size >= new_size); if (!ret && last_size > new_size) last_size = new_size; btrfs_ordered_update_i_size(inode, last_size, NULL); } btrfs_free_path(path); return ret; } /* * btrfs_truncate_block - read, zero a chunk and write a block * @inode - inode that we're zeroing * @from - the offset to start zeroing * @len - the length to zero, 0 to zero the entire range respective to the * offset * @front - zero up to the offset instead of from the offset on * * This will find the block for the "from" offset and cow the block and zero the * part we want to zero. This is used with truncate and hole punching. */ int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len, int front) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct address_space *mapping = inode->i_mapping; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; struct extent_changeset *data_reserved = NULL; char *kaddr; u32 blocksize = fs_info->sectorsize; pgoff_t index = from >> PAGE_SHIFT; unsigned offset = from & (blocksize - 1); struct page *page; gfp_t mask = btrfs_alloc_write_mask(mapping); int ret = 0; u64 block_start; u64 block_end; if (IS_ALIGNED(offset, blocksize) && (!len || IS_ALIGNED(len, blocksize))) goto out; block_start = round_down(from, blocksize); block_end = block_start + blocksize - 1; ret = btrfs_delalloc_reserve_space(inode, &data_reserved, block_start, blocksize); if (ret) goto out; again: page = find_or_create_page(mapping, index, mask); if (!page) { btrfs_delalloc_release_space(inode, data_reserved, block_start, blocksize, true); btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, true); ret = -ENOMEM; goto out; } if (!PageUptodate(page)) { ret = btrfs_readpage(NULL, page); lock_page(page); if (page->mapping != mapping) { unlock_page(page); put_page(page); goto again; } if (!PageUptodate(page)) { ret = -EIO; goto out_unlock; } } wait_on_page_writeback(page); lock_extent_bits(io_tree, block_start, block_end, &cached_state); set_page_extent_mapped(page); ordered = btrfs_lookup_ordered_extent(inode, block_start); if (ordered) { unlock_extent_cached(io_tree, block_start, block_end, &cached_state); unlock_page(page); put_page(page); btrfs_start_ordered_extent(inode, ordered, 1); btrfs_put_ordered_extent(ordered); goto again; } clear_extent_bit(&BTRFS_I(inode)->io_tree, block_start, block_end, EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, &cached_state); ret = btrfs_set_extent_delalloc(inode, block_start, block_end, 0, &cached_state, 0); if (ret) { unlock_extent_cached(io_tree, block_start, block_end, &cached_state); goto out_unlock; } if (offset != blocksize) { if (!len) len = blocksize - offset; kaddr = kmap(page); if (front) memset(kaddr + (block_start - page_offset(page)), 0, offset); else memset(kaddr + (block_start - page_offset(page)) + offset, 0, len); flush_dcache_page(page); kunmap(page); } ClearPageChecked(page); set_page_dirty(page); unlock_extent_cached(io_tree, block_start, block_end, &cached_state); out_unlock: if (ret) btrfs_delalloc_release_space(inode, data_reserved, block_start, blocksize, true); btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, (ret != 0)); unlock_page(page); put_page(page); out: extent_changeset_free(data_reserved); return ret; } static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode, u64 offset, u64 len) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_trans_handle *trans; int ret; /* * Still need to make sure the inode looks like it's been updated so * that any holes get logged if we fsync. */ if (btrfs_fs_incompat(fs_info, NO_HOLES)) { BTRFS_I(inode)->last_trans = fs_info->generation; BTRFS_I(inode)->last_sub_trans = root->log_transid; BTRFS_I(inode)->last_log_commit = root->last_log_commit; return 0; } /* * 1 - for the one we're dropping * 1 - for the one we're adding * 1 - for updating the inode. */ trans = btrfs_start_transaction(root, 3); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1); if (ret) { btrfs_abort_transaction(trans, ret); btrfs_end_transaction(trans); return ret; } ret = btrfs_insert_file_extent(trans, root, btrfs_ino(BTRFS_I(inode)), offset, 0, 0, len, 0, len, 0, 0, 0); if (ret) btrfs_abort_transaction(trans, ret); else btrfs_update_inode(trans, root, inode); btrfs_end_transaction(trans); return ret; } /* * This function puts in dummy file extents for the area we're creating a hole * for. So if we are truncating this file to a larger size we need to insert * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for * the range between oldsize and size */ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_map *em = NULL; struct extent_state *cached_state = NULL; struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; u64 hole_start = ALIGN(oldsize, fs_info->sectorsize); u64 block_end = ALIGN(size, fs_info->sectorsize); u64 last_byte; u64 cur_offset; u64 hole_size; int err = 0; /* * If our size started in the middle of a block we need to zero out the * rest of the block before we expand the i_size, otherwise we could * expose stale data. */ err = btrfs_truncate_block(inode, oldsize, 0, 0); if (err) return err; if (size <= hole_start) return 0; while (1) { struct btrfs_ordered_extent *ordered; lock_extent_bits(io_tree, hole_start, block_end - 1, &cached_state); ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), hole_start, block_end - hole_start); if (!ordered) break; unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state); btrfs_start_ordered_extent(inode, ordered, 1); btrfs_put_ordered_extent(ordered); } cur_offset = hole_start; while (1) { em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset, block_end - cur_offset, 0); if (IS_ERR(em)) { err = PTR_ERR(em); em = NULL; break; } last_byte = min(extent_map_end(em), block_end); last_byte = ALIGN(last_byte, fs_info->sectorsize); if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) { struct extent_map *hole_em; hole_size = last_byte - cur_offset; err = maybe_insert_hole(root, inode, cur_offset, hole_size); if (err) break; btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, cur_offset + hole_size - 1, 0); hole_em = alloc_extent_map(); if (!hole_em) { set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); goto next; } hole_em->start = cur_offset; hole_em->len = hole_size; hole_em->orig_start = cur_offset; hole_em->block_start = EXTENT_MAP_HOLE; hole_em->block_len = 0; hole_em->orig_block_len = 0; hole_em->ram_bytes = hole_size; hole_em->bdev = fs_info->fs_devices->latest_bdev; hole_em->compress_type = BTRFS_COMPRESS_NONE; hole_em->generation = fs_info->generation; while (1) { write_lock(&em_tree->lock); err = add_extent_mapping(em_tree, hole_em, 1); write_unlock(&em_tree->lock); if (err != -EEXIST) break; btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, cur_offset + hole_size - 1, 0); } free_extent_map(hole_em); } next: free_extent_map(em); em = NULL; cur_offset = last_byte; if (cur_offset >= block_end) break; } free_extent_map(em); unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state); return err; } static int btrfs_setsize(struct inode *inode, struct iattr *attr) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; loff_t oldsize = i_size_read(inode); loff_t newsize = attr->ia_size; int mask = attr->ia_valid; int ret; /* * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a * special case where we need to update the times despite not having * these flags set. For all other operations the VFS set these flags * explicitly if it wants a timestamp update. */ if (newsize != oldsize) { inode_inc_iversion(inode); if (!(mask & (ATTR_CTIME | ATTR_MTIME))) inode->i_ctime = inode->i_mtime = current_time(inode); } if (newsize > oldsize) { /* * Don't do an expanding truncate while snapshotting is ongoing. * This is to ensure the snapshot captures a fully consistent * state of this file - if the snapshot captures this expanding * truncation, it must capture all writes that happened before * this truncation. */ btrfs_wait_for_snapshot_creation(root); ret = btrfs_cont_expand(inode, oldsize, newsize); if (ret) { btrfs_end_write_no_snapshotting(root); return ret; } trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { btrfs_end_write_no_snapshotting(root); return PTR_ERR(trans); } i_size_write(inode, newsize); btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL); pagecache_isize_extended(inode, oldsize, newsize); ret = btrfs_update_inode(trans, root, inode); btrfs_end_write_no_snapshotting(root); btrfs_end_transaction(trans); } else { /* * We're truncating a file that used to have good data down to * zero. Make sure it gets into the ordered flush list so that * any new writes get down to disk quickly. */ if (newsize == 0) set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE, &BTRFS_I(inode)->runtime_flags); truncate_setsize(inode, newsize); /* Disable nonlocked read DIO to avoid the endless truncate */ btrfs_inode_block_unlocked_dio(BTRFS_I(inode)); inode_dio_wait(inode); btrfs_inode_resume_unlocked_dio(BTRFS_I(inode)); ret = btrfs_truncate(inode, newsize == oldsize); if (ret && inode->i_nlink) { int err; /* * Truncate failed, so fix up the in-memory size. We * adjusted disk_i_size down as we removed extents, so * wait for disk_i_size to be stable and then update the * in-memory size to match. */ err = btrfs_wait_ordered_range(inode, 0, (u64)-1); if (err) return err; i_size_write(inode, BTRFS_I(inode)->disk_i_size); } } return ret; } static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) { struct inode *inode = d_inode(dentry); struct btrfs_root *root = BTRFS_I(inode)->root; int err; if (btrfs_root_readonly(root)) return -EROFS; err = setattr_prepare(dentry, attr); if (err) return err; if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) { err = btrfs_setsize(inode, attr); if (err) return err; } if (attr->ia_valid) { setattr_copy(inode, attr); inode_inc_iversion(inode); err = btrfs_dirty_inode(inode); if (!err && attr->ia_valid & ATTR_MODE) err = posix_acl_chmod(inode, inode->i_mode); } return err; } /* * While truncating the inode pages during eviction, we get the VFS calling * btrfs_invalidatepage() against each page of the inode. This is slow because * the calls to btrfs_invalidatepage() result in a huge amount of calls to * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting * extent_state structures over and over, wasting lots of time. * * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all * those expensive operations on a per page basis and do only the ordered io * finishing, while we release here the extent_map and extent_state structures, * without the excessive merging and splitting. */ static void evict_inode_truncate_pages(struct inode *inode) { struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree; struct rb_node *node; ASSERT(inode->i_state & I_FREEING); truncate_inode_pages_final(&inode->i_data); write_lock(&map_tree->lock); while (!RB_EMPTY_ROOT(&map_tree->map.rb_root)) { struct extent_map *em; node = rb_first_cached(&map_tree->map); em = rb_entry(node, struct extent_map, rb_node); clear_bit(EXTENT_FLAG_PINNED, &em->flags); clear_bit(EXTENT_FLAG_LOGGING, &em->flags); remove_extent_mapping(map_tree, em); free_extent_map(em); if (need_resched()) { write_unlock(&map_tree->lock); cond_resched(); write_lock(&map_tree->lock); } } write_unlock(&map_tree->lock); /* * Keep looping until we have no more ranges in the io tree. * We can have ongoing bios started by readpages (called from readahead) * that have their endio callback (extent_io.c:end_bio_extent_readpage) * still in progress (unlocked the pages in the bio but did not yet * unlocked the ranges in the io tree). Therefore this means some * ranges can still be locked and eviction started because before * submitting those bios, which are executed by a separate task (work * queue kthread), inode references (inode->i_count) were not taken * (which would be dropped in the end io callback of each bio). * Therefore here we effectively end up waiting for those bios and * anyone else holding locked ranges without having bumped the inode's * reference count - if we don't do it, when they access the inode's * io_tree to unlock a range it may be too late, leading to an * use-after-free issue. */ spin_lock(&io_tree->lock); while (!RB_EMPTY_ROOT(&io_tree->state)) { struct extent_state *state; struct extent_state *cached_state = NULL; u64 start; u64 end; unsigned state_flags; node = rb_first(&io_tree->state); state = rb_entry(node, struct extent_state, rb_node); start = state->start; end = state->end; state_flags = state->state; spin_unlock(&io_tree->lock); lock_extent_bits(io_tree, start, end, &cached_state); /* * If still has DELALLOC flag, the extent didn't reach disk, * and its reserved space won't be freed by delayed_ref. * So we need to free its reserved space here. * (Refer to comment in btrfs_invalidatepage, case 2) * * Note, end is the bytenr of last byte, so we need + 1 here. */ if (state_flags & EXTENT_DELALLOC) btrfs_qgroup_free_data(inode, NULL, start, end - start + 1); clear_extent_bit(io_tree, start, end, EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1, &cached_state); cond_resched(); spin_lock(&io_tree->lock); } spin_unlock(&io_tree->lock); } static struct btrfs_trans_handle *evict_refill_and_join(struct btrfs_root *root, struct btrfs_block_rsv *rsv) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; int failures = 0; for (;;) { struct btrfs_trans_handle *trans; int ret; ret = btrfs_block_rsv_refill(root, rsv, rsv->size, BTRFS_RESERVE_FLUSH_LIMIT); if (ret && ++failures > 2) { btrfs_warn(fs_info, "could not allocate space for a delete; will truncate on mount"); return ERR_PTR(-ENOSPC); } trans = btrfs_join_transaction(root); if (IS_ERR(trans) || !ret) return trans; /* * Try to steal from the global reserve if there is space for * it. */ if (!btrfs_check_space_for_delayed_refs(fs_info) && !btrfs_block_rsv_migrate(global_rsv, rsv, rsv->size, 0)) return trans; /* If not, commit and try again. */ ret = btrfs_commit_transaction(trans); if (ret) return ERR_PTR(ret); } } void btrfs_evict_inode(struct inode *inode) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_block_rsv *rsv; int ret; trace_btrfs_inode_evict(inode); if (!root) { clear_inode(inode); return; } evict_inode_truncate_pages(inode); if (inode->i_nlink && ((btrfs_root_refs(&root->root_item) != 0 && root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) || btrfs_is_free_space_inode(BTRFS_I(inode)))) goto no_delete; if (is_bad_inode(inode)) goto no_delete; btrfs_free_io_failure_record(BTRFS_I(inode), 0, (u64)-1); if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) goto no_delete; if (inode->i_nlink > 0) { BUG_ON(btrfs_root_refs(&root->root_item) != 0 && root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID); goto no_delete; } ret = btrfs_commit_inode_delayed_inode(BTRFS_I(inode)); if (ret) goto no_delete; rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP); if (!rsv) goto no_delete; rsv->size = btrfs_calc_trunc_metadata_size(fs_info, 1); rsv->failfast = 1; btrfs_i_size_write(BTRFS_I(inode), 0); while (1) { trans = evict_refill_and_join(root, rsv); if (IS_ERR(trans)) goto free_rsv; trans->block_rsv = rsv; ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0); trans->block_rsv = &fs_info->trans_block_rsv; btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); if (ret && ret != -ENOSPC && ret != -EAGAIN) goto free_rsv; else if (!ret) break; } /* * Errors here aren't a big deal, it just means we leave orphan items in * the tree. They will be cleaned up on the next mount. If the inode * number gets reused, cleanup deletes the orphan item without doing * anything, and unlink reuses the existing orphan item. * * If it turns out that we are dropping too many of these, we might want * to add a mechanism for retrying these after a commit. */ trans = evict_refill_and_join(root, rsv); if (!IS_ERR(trans)) { trans->block_rsv = rsv; btrfs_orphan_del(trans, BTRFS_I(inode)); trans->block_rsv = &fs_info->trans_block_rsv; btrfs_end_transaction(trans); } if (!(root == fs_info->tree_root || root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)) btrfs_return_ino(root, btrfs_ino(BTRFS_I(inode))); free_rsv: btrfs_free_block_rsv(fs_info, rsv); no_delete: /* * If we didn't successfully delete, the orphan item will still be in * the tree and we'll retry on the next mount. Again, we might also want * to retry these periodically in the future. */ btrfs_remove_delayed_node(BTRFS_I(inode)); clear_inode(inode); } /* * this returns the key found in the dir entry in the location pointer. * If no dir entries were found, returns -ENOENT. * If found a corrupted location in dir entry, returns -EUCLEAN. */ static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry, struct btrfs_key *location) { const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; struct btrfs_dir_item *di; struct btrfs_path *path; struct btrfs_root *root = BTRFS_I(dir)->root; int ret = 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(BTRFS_I(dir)), name, namelen, 0); if (IS_ERR_OR_NULL(di)) { ret = di ? PTR_ERR(di) : -ENOENT; goto out; } btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); if (location->type != BTRFS_INODE_ITEM_KEY && location->type != BTRFS_ROOT_ITEM_KEY) { ret = -EUCLEAN; btrfs_warn(root->fs_info, "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))", __func__, name, btrfs_ino(BTRFS_I(dir)), location->objectid, location->type, location->offset); } out: btrfs_free_path(path); return ret; } /* * when we hit a tree root in a directory, the btrfs part of the inode * needs to be changed to reflect the root directory of the tree root. This * is kind of like crossing a mount point. */ static int fixup_tree_root_location(struct btrfs_fs_info *fs_info, struct inode *dir, struct dentry *dentry, struct btrfs_key *location, struct btrfs_root **sub_root) { struct btrfs_path *path; struct btrfs_root *new_root; struct btrfs_root_ref *ref; struct extent_buffer *leaf; struct btrfs_key key; int ret; int err = 0; path = btrfs_alloc_path(); if (!path) { err = -ENOMEM; goto out; } err = -ENOENT; key.objectid = BTRFS_I(dir)->root->root_key.objectid; key.type = BTRFS_ROOT_REF_KEY; key.offset = location->objectid; ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); if (ret) { if (ret < 0) err = ret; goto out; } leaf = path->nodes[0]; ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(BTRFS_I(dir)) || btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len) goto out; ret = memcmp_extent_buffer(leaf, dentry->d_name.name, (unsigned long)(ref + 1), dentry->d_name.len); if (ret) goto out; btrfs_release_path(path); new_root = btrfs_read_fs_root_no_name(fs_info, location); if (IS_ERR(new_root)) { err = PTR_ERR(new_root); goto out; } *sub_root = new_root; location->objectid = btrfs_root_dirid(&new_root->root_item); location->type = BTRFS_INODE_ITEM_KEY; location->offset = 0; err = 0; out: btrfs_free_path(path); return err; } static void inode_tree_add(struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_inode *entry; struct rb_node **p; struct rb_node *parent; struct rb_node *new = &BTRFS_I(inode)->rb_node; u64 ino = btrfs_ino(BTRFS_I(inode)); if (inode_unhashed(inode)) return; parent = NULL; spin_lock(&root->inode_lock); p = &root->inode_tree.rb_node; while (*p) { parent = *p; entry = rb_entry(parent, struct btrfs_inode, rb_node); if (ino < btrfs_ino(entry)) p = &parent->rb_left; else if (ino > btrfs_ino(entry)) p = &parent->rb_right; else { WARN_ON(!(entry->vfs_inode.i_state & (I_WILL_FREE | I_FREEING))); rb_replace_node(parent, new, &root->inode_tree); RB_CLEAR_NODE(parent); spin_unlock(&root->inode_lock); return; } } rb_link_node(new, parent, p); rb_insert_color(new, &root->inode_tree); spin_unlock(&root->inode_lock); } static void inode_tree_del(struct inode *inode) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; int empty = 0; spin_lock(&root->inode_lock); if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree); RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); empty = RB_EMPTY_ROOT(&root->inode_tree); } spin_unlock(&root->inode_lock); if (empty && btrfs_root_refs(&root->root_item) == 0) { synchronize_srcu(&fs_info->subvol_srcu); spin_lock(&root->inode_lock); empty = RB_EMPTY_ROOT(&root->inode_tree); spin_unlock(&root->inode_lock); if (empty) btrfs_add_dead_root(root); } } static int btrfs_init_locked_inode(struct inode *inode, void *p) { struct btrfs_iget_args *args = p; inode->i_ino = args->location->objectid; memcpy(&BTRFS_I(inode)->location, args->location, sizeof(*args->location)); BTRFS_I(inode)->root = args->root; return 0; } static int btrfs_find_actor(struct inode *inode, void *opaque) { struct btrfs_iget_args *args = opaque; return args->location->objectid == BTRFS_I(inode)->location.objectid && args->root == BTRFS_I(inode)->root; } static struct inode *btrfs_iget_locked(struct super_block *s, struct btrfs_key *location, struct btrfs_root *root) { struct inode *inode; struct btrfs_iget_args args; unsigned long hashval = btrfs_inode_hash(location->objectid, root); args.location = location; args.root = root; inode = iget5_locked(s, hashval, btrfs_find_actor, btrfs_init_locked_inode, (void *)&args); return inode; } /* Get an inode object given its location and corresponding root. * Returns in *is_new if the inode was read from disk */ struct inode *btrfs_iget_path(struct super_block *s, struct btrfs_key *location, struct btrfs_root *root, int *new, struct btrfs_path *path) { struct inode *inode; inode = btrfs_iget_locked(s, location, root); if (!inode) return ERR_PTR(-ENOMEM); if (inode->i_state & I_NEW) { int ret; ret = btrfs_read_locked_inode(inode, path); if (!ret) { inode_tree_add(inode); unlock_new_inode(inode); if (new) *new = 1; } else { iget_failed(inode); /* * ret > 0 can come from btrfs_search_slot called by * btrfs_read_locked_inode, this means the inode item * was not found. */ if (ret > 0) ret = -ENOENT; inode = ERR_PTR(ret); } } return inode; } struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, struct btrfs_root *root, int *new) { return btrfs_iget_path(s, location, root, new, NULL); } static struct inode *new_simple_dir(struct super_block *s, struct btrfs_key *key, struct btrfs_root *root) { struct inode *inode = new_inode(s); if (!inode) return ERR_PTR(-ENOMEM); BTRFS_I(inode)->root = root; memcpy(&BTRFS_I(inode)->location, key, sizeof(*key)); set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags); inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID; inode->i_op = &btrfs_dir_ro_inode_operations; inode->i_opflags &= ~IOP_XATTR; inode->i_fop = &simple_dir_operations; inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO; inode->i_mtime = current_time(inode); inode->i_atime = inode->i_mtime; inode->i_ctime = inode->i_mtime; BTRFS_I(inode)->i_otime = inode->i_mtime; return inode; } struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) { struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); struct inode *inode; struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_root *sub_root = root; struct btrfs_key location; int index; int ret = 0; if (dentry->d_name.len > BTRFS_NAME_LEN) return ERR_PTR(-ENAMETOOLONG); ret = btrfs_inode_by_name(dir, dentry, &location); if (ret < 0) return ERR_PTR(ret); if (location.type == BTRFS_INODE_ITEM_KEY) { inode = btrfs_iget(dir->i_sb, &location, root, NULL); return inode; } index = srcu_read_lock(&fs_info->subvol_srcu); ret = fixup_tree_root_location(fs_info, dir, dentry, &location, &sub_root); if (ret < 0) { if (ret != -ENOENT) inode = ERR_PTR(ret); else inode = new_simple_dir(dir->i_sb, &location, sub_root); } else { inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL); } srcu_read_unlock(&fs_info->subvol_srcu, index); if (!IS_ERR(inode) && root != sub_root) { down_read(&fs_info->cleanup_work_sem); if (!sb_rdonly(inode->i_sb)) ret = btrfs_orphan_cleanup(sub_root); up_read(&fs_info->cleanup_work_sem); if (ret) { iput(inode); inode = ERR_PTR(ret); } } return inode; } static int btrfs_dentry_delete(const struct dentry *dentry) { struct btrfs_root *root; struct inode *inode = d_inode(dentry); if (!inode && !IS_ROOT(dentry)) inode = d_inode(dentry->d_parent); if (inode) { root = BTRFS_I(inode)->root; if (btrfs_root_refs(&root->root_item) == 0) return 1; if (btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) return 1; } return 0; } static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { struct inode *inode = btrfs_lookup_dentry(dir, dentry); if (inode == ERR_PTR(-ENOENT)) inode = NULL; return d_splice_alias(inode, dentry); } unsigned char btrfs_filetype_table[] = { DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK }; /* * All this infrastructure exists because dir_emit can fault, and we are holding * the tree lock when doing readdir. For now just allocate a buffer and copy * our information into that, and then dir_emit from the buffer. This is * similar to what NFS does, only we don't keep the buffer around in pagecache * because I'm afraid I'll mess that up. Long term we need to make filldir do * copy_to_user_inatomic so we don't have to worry about page faulting under the * tree lock. */ static int btrfs_opendir(struct inode *inode, struct file *file) { struct btrfs_file_private *private; private = kzalloc(sizeof(struct btrfs_file_private), GFP_KERNEL); if (!private) return -ENOMEM; private->filldir_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); if (!private->filldir_buf) { kfree(private); return -ENOMEM; } file->private_data = private; return 0; } struct dir_entry { u64 ino; u64 offset; unsigned type; int name_len; }; static int btrfs_filldir(void *addr, int entries, struct dir_context *ctx) { while (entries--) { struct dir_entry *entry = addr; char *name = (char *)(entry + 1); ctx->pos = get_unaligned(&entry->offset); if (!dir_emit(ctx, name, get_unaligned(&entry->name_len), get_unaligned(&entry->ino), get_unaligned(&entry->type))) return 1; addr += sizeof(struct dir_entry) + get_unaligned(&entry->name_len); ctx->pos++; } return 0; } static int btrfs_real_readdir(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_file_private *private = file->private_data; struct btrfs_dir_item *di; struct btrfs_key key; struct btrfs_key found_key; struct btrfs_path *path; void *addr; struct list_head ins_list; struct list_head del_list; int ret; struct extent_buffer *leaf; int slot; char *name_ptr; int name_len; int entries = 0; int total_len = 0; bool put = false; struct btrfs_key location; if (!dir_emit_dots(file, ctx)) return 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; addr = private->filldir_buf; path->reada = READA_FORWARD; INIT_LIST_HEAD(&ins_list); INIT_LIST_HEAD(&del_list); put = btrfs_readdir_get_delayed_items(inode, &ins_list, &del_list); again: key.type = BTRFS_DIR_INDEX_KEY; key.offset = ctx->pos; key.objectid = btrfs_ino(BTRFS_I(inode)); ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto err; while (1) { struct dir_entry *entry; leaf = path->nodes[0]; slot = path->slots[0]; if (slot >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) goto err; else if (ret > 0) break; continue; } btrfs_item_key_to_cpu(leaf, &found_key, slot); if (found_key.objectid != key.objectid) break; if (found_key.type != BTRFS_DIR_INDEX_KEY) break; if (found_key.offset < ctx->pos) goto next; if (btrfs_should_delete_dir_index(&del_list, found_key.offset)) goto next; di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); name_len = btrfs_dir_name_len(leaf, di); if ((total_len + sizeof(struct dir_entry) + name_len) >= PAGE_SIZE) { btrfs_release_path(path); ret = btrfs_filldir(private->filldir_buf, entries, ctx); if (ret) goto nopos; addr = private->filldir_buf; entries = 0; total_len = 0; goto again; } entry = addr; put_unaligned(name_len, &entry->name_len); name_ptr = (char *)(entry + 1); read_extent_buffer(leaf, name_ptr, (unsigned long)(di + 1), name_len); put_unaligned(btrfs_filetype_table[btrfs_dir_type(leaf, di)], &entry->type); btrfs_dir_item_key_to_cpu(leaf, di, &location); put_unaligned(location.objectid, &entry->ino); put_unaligned(found_key.offset, &entry->offset); entries++; addr += sizeof(struct dir_entry) + name_len; total_len += sizeof(struct dir_entry) + name_len; next: path->slots[0]++; } btrfs_release_path(path); ret = btrfs_filldir(private->filldir_buf, entries, ctx); if (ret) goto nopos; ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list); if (ret) goto nopos; /* * Stop new entries from being returned after we return the last * entry. * * New directory entries are assigned a strictly increasing * offset. This means that new entries created during readdir * are *guaranteed* to be seen in the future by that readdir. * This has broken buggy programs which operate on names as * they're returned by readdir. Until we re-use freed offsets * we have this hack to stop new entries from being returned * under the assumption that they'll never reach this huge * offset. * * This is being careful not to overflow 32bit loff_t unless the * last entry requires it because doing so has broken 32bit apps * in the past. */ if (ctx->pos >= INT_MAX) ctx->pos = LLONG_MAX; else ctx->pos = INT_MAX; nopos: ret = 0; err: if (put) btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list); btrfs_free_path(path); return ret; } /* * This is somewhat expensive, updating the tree every time the * inode changes. But, it is most likely to find the inode in cache. * FIXME, needs more benchmarking...there are no reasons other than performance * to keep or drop this code. */ static int btrfs_dirty_inode(struct inode *inode) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; int ret; if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags)) return 0; trans = btrfs_join_transaction(root); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_update_inode(trans, root, inode); if (ret && ret == -ENOSPC) { /* whoops, lets try again with the full transaction */ btrfs_end_transaction(trans); trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_update_inode(trans, root, inode); } btrfs_end_transaction(trans); if (BTRFS_I(inode)->delayed_node) btrfs_balance_delayed_items(fs_info); return ret; } /* * This is a copy of file_update_time. We need this so we can return error on * ENOSPC for updating the inode in the case of file write and mmap writes. */ static int btrfs_update_time(struct inode *inode, struct timespec64 *now, int flags) { struct btrfs_root *root = BTRFS_I(inode)->root; bool dirty = flags & ~S_VERSION; if (btrfs_root_readonly(root)) return -EROFS; if (flags & S_VERSION) dirty |= inode_maybe_inc_iversion(inode, dirty); if (flags & S_CTIME) inode->i_ctime = *now; if (flags & S_MTIME) inode->i_mtime = *now; if (flags & S_ATIME) inode->i_atime = *now; return dirty ? btrfs_dirty_inode(inode) : 0; } /* * find the highest existing sequence number in a directory * and then set the in-memory index_cnt variable to reflect * free sequence numbers */ static int btrfs_set_inode_index_count(struct btrfs_inode *inode) { struct btrfs_root *root = inode->root; struct btrfs_key key, found_key; struct btrfs_path *path; struct extent_buffer *leaf; int ret; key.objectid = btrfs_ino(inode); key.type = BTRFS_DIR_INDEX_KEY; key.offset = (u64)-1; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; /* FIXME: we should be able to handle this */ if (ret == 0) goto out; ret = 0; /* * MAGIC NUMBER EXPLANATION: * since we search a directory based on f_pos we have to start at 2 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody * else has to start at 2 */ if (path->slots[0] == 0) { inode->index_cnt = 2; goto out; } path->slots[0]--; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); if (found_key.objectid != btrfs_ino(inode) || found_key.type != BTRFS_DIR_INDEX_KEY) { inode->index_cnt = 2; goto out; } inode->index_cnt = found_key.offset + 1; out: btrfs_free_path(path); return ret; } /* * helper to find a free sequence number in a given directory. This current * code is very simple, later versions will do smarter things in the btree */ int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index) { int ret = 0; if (dir->index_cnt == (u64)-1) { ret = btrfs_inode_delayed_dir_index_count(dir); if (ret) { ret = btrfs_set_inode_index_count(dir); if (ret) return ret; } } *index = dir->index_cnt; dir->index_cnt++; return ret; } static int btrfs_insert_inode_locked(struct inode *inode) { struct btrfs_iget_args args; args.location = &BTRFS_I(inode)->location; args.root = BTRFS_I(inode)->root; return insert_inode_locked4(inode, btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root), btrfs_find_actor, &args); } /* * Inherit flags from the parent inode. * * Currently only the compression flags and the cow flags are inherited. */ static void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) { unsigned int flags; if (!dir) return; flags = BTRFS_I(dir)->flags; if (flags & BTRFS_INODE_NOCOMPRESS) { BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS; BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; } else if (flags & BTRFS_INODE_COMPRESS) { BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS; BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS; } if (flags & BTRFS_INODE_NODATACOW) { BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; if (S_ISREG(inode->i_mode)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; } btrfs_sync_inode_flags_to_i_flags(inode); } static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *dir, const char *name, int name_len, u64 ref_objectid, u64 objectid, umode_t mode, u64 *index) { struct btrfs_fs_info *fs_info = root->fs_info; struct inode *inode; struct btrfs_inode_item *inode_item; struct btrfs_key *location; struct btrfs_path *path; struct btrfs_inode_ref *ref; struct btrfs_key key[2]; u32 sizes[2]; int nitems = name ? 2 : 1; unsigned long ptr; int ret; path = btrfs_alloc_path(); if (!path) return ERR_PTR(-ENOMEM); inode = new_inode(fs_info->sb); if (!inode) { btrfs_free_path(path); return ERR_PTR(-ENOMEM); } /* * O_TMPFILE, set link count to 0, so that after this point, * we fill in an inode item with the correct link count. */ if (!name) set_nlink(inode, 0); /* * we have to initialize this early, so we can reclaim the inode * number if we fail afterwards in this function. */ inode->i_ino = objectid; if (dir && name) { trace_btrfs_inode_request(dir); ret = btrfs_set_inode_index(BTRFS_I(dir), index); if (ret) { btrfs_free_path(path); iput(inode); return ERR_PTR(ret); } } else if (dir) { *index = 0; } /* * index_cnt is ignored for everything but a dir, * btrfs_set_inode_index_count has an explanation for the magic * number */ BTRFS_I(inode)->index_cnt = 2; BTRFS_I(inode)->dir_index = *index; BTRFS_I(inode)->root = root; BTRFS_I(inode)->generation = trans->transid; inode->i_generation = BTRFS_I(inode)->generation; /* * We could have gotten an inode number from somebody who was fsynced * and then removed in this same transaction, so let's just set full * sync since it will be a full sync anyway and this will blow away the * old info in the log. */ set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); key[0].objectid = objectid; key[0].type = BTRFS_INODE_ITEM_KEY; key[0].offset = 0; sizes[0] = sizeof(struct btrfs_inode_item); if (name) { /* * Start new inodes with an inode_ref. This is slightly more * efficient for small numbers of hard links since they will * be packed into one item. Extended refs will kick in if we * add more hard links than can fit in the ref item. */ key[1].objectid = objectid; key[1].type = BTRFS_INODE_REF_KEY; key[1].offset = ref_objectid; sizes[1] = name_len + sizeof(*ref); } location = &BTRFS_I(inode)->location; location->objectid = objectid; location->offset = 0; location->type = BTRFS_INODE_ITEM_KEY; ret = btrfs_insert_inode_locked(inode); if (ret < 0) { iput(inode); goto fail; } path->leave_spinning = 1; ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems); if (ret != 0) goto fail_unlock; inode_init_owner(inode, dir, mode); inode_set_bytes(inode, 0); inode->i_mtime = current_time(inode); inode->i_atime = inode->i_mtime; inode->i_ctime = inode->i_mtime; BTRFS_I(inode)->i_otime = inode->i_mtime; inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_inode_item); memzero_extent_buffer(path->nodes[0], (unsigned long)inode_item, sizeof(*inode_item)); fill_inode_item(trans, path->nodes[0], inode_item, inode); if (name) { ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, struct btrfs_inode_ref); btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len); btrfs_set_inode_ref_index(path->nodes[0], ref, *index); ptr = (unsigned long)(ref + 1); write_extent_buffer(path->nodes[0], name, ptr, name_len); } btrfs_mark_buffer_dirty(path->nodes[0]); btrfs_free_path(path); btrfs_inherit_iflags(inode, dir); if (S_ISREG(mode)) { if (btrfs_test_opt(fs_info, NODATASUM)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; if (btrfs_test_opt(fs_info, NODATACOW)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW | BTRFS_INODE_NODATASUM; } inode_tree_add(inode); trace_btrfs_inode_new(inode); btrfs_set_inode_last_trans(trans, inode); btrfs_update_root_times(trans, root); ret = btrfs_inode_inherit_props(trans, inode, dir); if (ret) btrfs_err(fs_info, "error inheriting props for ino %llu (root %llu): %d", btrfs_ino(BTRFS_I(inode)), root->root_key.objectid, ret); return inode; fail_unlock: discard_new_inode(inode); fail: if (dir && name) BTRFS_I(dir)->index_cnt--; btrfs_free_path(path); return ERR_PTR(ret); } static inline u8 btrfs_inode_type(struct inode *inode) { return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT]; } /* * utility function to add 'inode' into 'parent_inode' with * a give name and a given sequence number. * if 'add_backref' is true, also insert a backref from the * inode to the parent directory. */ int btrfs_add_link(struct btrfs_trans_handle *trans, struct btrfs_inode *parent_inode, struct btrfs_inode *inode, const char *name, int name_len, int add_backref, u64 index) { int ret = 0; struct btrfs_key key; struct btrfs_root *root = parent_inode->root; u64 ino = btrfs_ino(inode); u64 parent_ino = btrfs_ino(parent_inode); if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { memcpy(&key, &inode->root->root_key, sizeof(key)); } else { key.objectid = ino; key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; } if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { ret = btrfs_add_root_ref(trans, key.objectid, root->root_key.objectid, parent_ino, index, name, name_len); } else if (add_backref) { ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino, parent_ino, index); } /* Nothing to clean up yet */ if (ret) return ret; ret = btrfs_insert_dir_item(trans, name, name_len, parent_inode, &key, btrfs_inode_type(&inode->vfs_inode), index); if (ret == -EEXIST || ret == -EOVERFLOW) goto fail_dir_item; else if (ret) { btrfs_abort_transaction(trans, ret); return ret; } btrfs_i_size_write(parent_inode, parent_inode->vfs_inode.i_size + name_len * 2); inode_inc_iversion(&parent_inode->vfs_inode); parent_inode->vfs_inode.i_mtime = parent_inode->vfs_inode.i_ctime = current_time(&parent_inode->vfs_inode); ret = btrfs_update_inode(trans, root, &parent_inode->vfs_inode); if (ret) btrfs_abort_transaction(trans, ret); return ret; fail_dir_item: if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { u64 local_index; int err; err = btrfs_del_root_ref(trans, key.objectid, root->root_key.objectid, parent_ino, &local_index, name, name_len); if (err) btrfs_abort_transaction(trans, err); } else if (add_backref) { u64 local_index; int err; err = btrfs_del_inode_ref(trans, root, name, name_len, ino, parent_ino, &local_index); if (err) btrfs_abort_transaction(trans, err); } /* Return the original error code */ return ret; } static int btrfs_add_nondir(struct btrfs_trans_handle *trans, struct btrfs_inode *dir, struct dentry *dentry, struct btrfs_inode *inode, int backref, u64 index) { int err = btrfs_add_link(trans, dir, inode, dentry->d_name.name, dentry->d_name.len, backref, index); if (err > 0) err = -EEXIST; return err; } static int btrfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev) { struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(dir)->root; struct inode *inode = NULL; int err; u64 objectid; u64 index = 0; /* * 2 for inode item and ref * 2 for dir items * 1 for xattr if selinux is on */ trans = btrfs_start_transaction(root, 5); if (IS_ERR(trans)) return PTR_ERR(trans); err = btrfs_find_free_ino(root, &objectid); if (err) goto out_unlock; inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, mode, &index); if (IS_ERR(inode)) { err = PTR_ERR(inode); inode = NULL; goto out_unlock; } /* * If the active LSM wants to access the inode during * d_instantiate it needs these. Smack checks to see * if the filesystem supports xattrs by looking at the * ops vector. */ inode->i_op = &btrfs_special_inode_operations; init_special_inode(inode, inode->i_mode, rdev); err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); if (err) goto out_unlock; err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 0, index); if (err) goto out_unlock; btrfs_update_inode(trans, root, inode); d_instantiate_new(dentry, inode); out_unlock: btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); if (err && inode) { inode_dec_link_count(inode); discard_new_inode(inode); } return err; } static int btrfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) { struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(dir)->root; struct inode *inode = NULL; int err; u64 objectid; u64 index = 0; /* * 2 for inode item and ref * 2 for dir items * 1 for xattr if selinux is on */ trans = btrfs_start_transaction(root, 5); if (IS_ERR(trans)) return PTR_ERR(trans); err = btrfs_find_free_ino(root, &objectid); if (err) goto out_unlock; inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, mode, &index); if (IS_ERR(inode)) { err = PTR_ERR(inode); inode = NULL; goto out_unlock; } /* * If the active LSM wants to access the inode during * d_instantiate it needs these. Smack checks to see * if the filesystem supports xattrs by looking at the * ops vector. */ inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; inode->i_mapping->a_ops = &btrfs_aops; err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); if (err) goto out_unlock; err = btrfs_update_inode(trans, root, inode); if (err) goto out_unlock; err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 0, index); if (err) goto out_unlock; BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; d_instantiate_new(dentry, inode); out_unlock: btrfs_end_transaction(trans); if (err && inode) { inode_dec_link_count(inode); discard_new_inode(inode); } btrfs_btree_balance_dirty(fs_info); return err; } static int btrfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) { struct btrfs_trans_handle *trans = NULL; struct btrfs_root *root = BTRFS_I(dir)->root; struct inode *inode = d_inode(old_dentry); struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); u64 index; int err; int drop_inode = 0; /* do not allow sys_link's with other subvols of the same device */ if (root->root_key.objectid != BTRFS_I(inode)->root->root_key.objectid) return -EXDEV; if (inode->i_nlink >= BTRFS_LINK_MAX) return -EMLINK; err = btrfs_set_inode_index(BTRFS_I(dir), &index); if (err) goto fail; /* * 2 items for inode and inode ref * 2 items for dir items * 1 item for parent inode * 1 item for orphan item deletion if O_TMPFILE */ trans = btrfs_start_transaction(root, inode->i_nlink ? 5 : 6); if (IS_ERR(trans)) { err = PTR_ERR(trans); trans = NULL; goto fail; } /* There are several dir indexes for this inode, clear the cache. */ BTRFS_I(inode)->dir_index = 0ULL; inc_nlink(inode); inode_inc_iversion(inode); inode->i_ctime = current_time(inode); ihold(inode); set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags); err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 1, index); if (err) { drop_inode = 1; } else { struct dentry *parent = dentry->d_parent; int ret; err = btrfs_update_inode(trans, root, inode); if (err) goto fail; if (inode->i_nlink == 1) { /* * If new hard link count is 1, it's a file created * with open(2) O_TMPFILE flag. */ err = btrfs_orphan_del(trans, BTRFS_I(inode)); if (err) goto fail; } BTRFS_I(inode)->last_link_trans = trans->transid; d_instantiate(dentry, inode); ret = btrfs_log_new_name(trans, BTRFS_I(inode), NULL, parent, true, NULL); if (ret == BTRFS_NEED_TRANS_COMMIT) { err = btrfs_commit_transaction(trans); trans = NULL; } } fail: if (trans) btrfs_end_transaction(trans); if (drop_inode) { inode_dec_link_count(inode); iput(inode); } btrfs_btree_balance_dirty(fs_info); return err; } static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); struct inode *inode = NULL; struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(dir)->root; int err = 0; u64 objectid = 0; u64 index = 0; /* * 2 items for inode and ref * 2 items for dir items * 1 for xattr if selinux is on */ trans = btrfs_start_transaction(root, 5); if (IS_ERR(trans)) return PTR_ERR(trans); err = btrfs_find_free_ino(root, &objectid); if (err) goto out_fail; inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, S_IFDIR | mode, &index); if (IS_ERR(inode)) { err = PTR_ERR(inode); inode = NULL; goto out_fail; } /* these must be set before we unlock the inode */ inode->i_op = &btrfs_dir_inode_operations; inode->i_fop = &btrfs_dir_file_operations; err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); if (err) goto out_fail; btrfs_i_size_write(BTRFS_I(inode), 0); err = btrfs_update_inode(trans, root, inode); if (err) goto out_fail; err = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), dentry->d_name.name, dentry->d_name.len, 0, index); if (err) goto out_fail; d_instantiate_new(dentry, inode); out_fail: btrfs_end_transaction(trans); if (err && inode) { inode_dec_link_count(inode); discard_new_inode(inode); } btrfs_btree_balance_dirty(fs_info); return err; } static noinline int uncompress_inline(struct btrfs_path *path, struct page *page, size_t pg_offset, u64 extent_offset, struct btrfs_file_extent_item *item) { int ret; struct extent_buffer *leaf = path->nodes[0]; char *tmp; size_t max_size; unsigned long inline_size; unsigned long ptr; int compress_type; WARN_ON(pg_offset != 0); compress_type = btrfs_file_extent_compression(leaf, item); max_size = btrfs_file_extent_ram_bytes(leaf, item); inline_size = btrfs_file_extent_inline_item_len(leaf, btrfs_item_nr(path->slots[0])); tmp = kmalloc(inline_size, GFP_NOFS); if (!tmp) return -ENOMEM; ptr = btrfs_file_extent_inline_start(item); read_extent_buffer(leaf, tmp, ptr, inline_size); max_size = min_t(unsigned long, PAGE_SIZE, max_size); ret = btrfs_decompress(compress_type, tmp, page, extent_offset, inline_size, max_size); /* * decompression code contains a memset to fill in any space between the end * of the uncompressed data and the end of max_size in case the decompressed * data ends up shorter than ram_bytes. That doesn't cover the hole between * the end of an inline extent and the beginning of the next block, so we * cover that region here. */ if (max_size + pg_offset < PAGE_SIZE) { char *map = kmap(page); memset(map + pg_offset + max_size, 0, PAGE_SIZE - max_size - pg_offset); kunmap(page); } kfree(tmp); return ret; } /* * a bit scary, this does extent mapping from logical file offset to the disk. * the ugly parts come from merging extents from the disk with the in-ram * representation. This gets more complex because of the data=ordered code, * where the in-ram extents might be locked pending data=ordered completion. * * This also copies inline extents directly into the page. */ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode, struct page *page, size_t pg_offset, u64 start, u64 len, int create) { struct btrfs_fs_info *fs_info = inode->root->fs_info; int ret; int err = 0; u64 extent_start = 0; u64 extent_end = 0; u64 objectid = btrfs_ino(inode); u32 found_type; struct btrfs_path *path = NULL; struct btrfs_root *root = inode->root; struct btrfs_file_extent_item *item; struct extent_buffer *leaf; struct btrfs_key found_key; struct extent_map *em = NULL; struct extent_map_tree *em_tree = &inode->extent_tree; struct extent_io_tree *io_tree = &inode->io_tree; const bool new_inline = !page || create; read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, start, len); if (em) em->bdev = fs_info->fs_devices->latest_bdev; read_unlock(&em_tree->lock); if (em) { if (em->start > start || em->start + em->len <= start) free_extent_map(em); else if (em->block_start == EXTENT_MAP_INLINE && page) free_extent_map(em); else goto out; } em = alloc_extent_map(); if (!em) { err = -ENOMEM; goto out; } em->bdev = fs_info->fs_devices->latest_bdev; em->start = EXTENT_MAP_HOLE; em->orig_start = EXTENT_MAP_HOLE; em->len = (u64)-1; em->block_len = (u64)-1; path = btrfs_alloc_path(); if (!path) { err = -ENOMEM; goto out; } /* Chances are we'll be called again, so go ahead and do readahead */ path->reada = READA_FORWARD; /* * Unless we're going to uncompress the inline extent, no sleep would * happen. */ path->leave_spinning = 1; ret = btrfs_lookup_file_extent(NULL, root, path, objectid, start, 0); if (ret < 0) { err = ret; goto out; } if (ret != 0) { if (path->slots[0] == 0) goto not_found; path->slots[0]--; } leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); /* are we inside the extent that was found? */ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); found_type = found_key.type; if (found_key.objectid != objectid || found_type != BTRFS_EXTENT_DATA_KEY) { /* * If we backup past the first extent we want to move forward * and see if there is an extent in front of us, otherwise we'll * say there is a hole for our whole search range which can * cause problems. */ extent_end = start; goto next; } found_type = btrfs_file_extent_type(leaf, item); extent_start = found_key.offset; if (found_type == BTRFS_FILE_EXTENT_REG || found_type == BTRFS_FILE_EXTENT_PREALLOC) { extent_end = extent_start + btrfs_file_extent_num_bytes(leaf, item); trace_btrfs_get_extent_show_fi_regular(inode, leaf, item, extent_start); } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { size_t size; size = btrfs_file_extent_ram_bytes(leaf, item); extent_end = ALIGN(extent_start + size, fs_info->sectorsize); trace_btrfs_get_extent_show_fi_inline(inode, leaf, item, path->slots[0], extent_start); } next: if (start >= extent_end) { path->slots[0]++; if (path->slots[0] >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) { err = ret; goto out; } if (ret > 0) goto not_found; leaf = path->nodes[0]; } btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); if (found_key.objectid != objectid || found_key.type != BTRFS_EXTENT_DATA_KEY) goto not_found; if (start + len <= found_key.offset) goto not_found; if (start > found_key.offset) goto next; em->start = start; em->orig_start = start; em->len = found_key.offset - start; goto not_found_em; } btrfs_extent_item_to_extent_map(inode, path, item, new_inline, em); if (found_type == BTRFS_FILE_EXTENT_REG || found_type == BTRFS_FILE_EXTENT_PREALLOC) { goto insert; } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { unsigned long ptr; char *map; size_t size; size_t extent_offset; size_t copy_size; if (new_inline) goto out; size = btrfs_file_extent_ram_bytes(leaf, item); extent_offset = page_offset(page) + pg_offset - extent_start; copy_size = min_t(u64, PAGE_SIZE - pg_offset, size - extent_offset); em->start = extent_start + extent_offset; em->len = ALIGN(copy_size, fs_info->sectorsize); em->orig_block_len = em->len; em->orig_start = em->start; ptr = btrfs_file_extent_inline_start(item) + extent_offset; btrfs_set_path_blocking(path); if (!PageUptodate(page)) { if (btrfs_file_extent_compression(leaf, item) != BTRFS_COMPRESS_NONE) { ret = uncompress_inline(path, page, pg_offset, extent_offset, item); if (ret) { err = ret; goto out; } } else { map = kmap(page); read_extent_buffer(leaf, map + pg_offset, ptr, copy_size); if (pg_offset + copy_size < PAGE_SIZE) { memset(map + pg_offset + copy_size, 0, PAGE_SIZE - pg_offset - copy_size); } kunmap(page); } flush_dcache_page(page); } set_extent_uptodate(io_tree, em->start, extent_map_end(em) - 1, NULL, GFP_NOFS); goto insert; } not_found: em->start = start; em->orig_start = start; em->len = len; not_found_em: em->block_start = EXTENT_MAP_HOLE; insert: btrfs_release_path(path); if (em->start > start || extent_map_end(em) <= start) { btrfs_err(fs_info, "bad extent! em: [%llu %llu] passed [%llu %llu]", em->start, em->len, start, len); err = -EIO; goto out; } err = 0; write_lock(&em_tree->lock); err = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len); write_unlock(&em_tree->lock); out: btrfs_free_path(path); trace_btrfs_get_extent(root, inode, em); if (err) { free_extent_map(em); return ERR_PTR(err); } BUG_ON(!em); /* Error is always set */ return em; } struct extent_map *btrfs_get_extent_fiemap(struct btrfs_inode *inode, struct page *page, size_t pg_offset, u64 start, u64 len, int create) { struct extent_map *em; struct extent_map *hole_em = NULL; u64 range_start = start; u64 end; u64 found; u64 found_end; int err = 0; em = btrfs_get_extent(inode, page, pg_offset, start, len, create); if (IS_ERR(em)) return em; /* * If our em maps to: * - a hole or * - a pre-alloc extent, * there might actually be delalloc bytes behind it. */ if (em->block_start != EXTENT_MAP_HOLE && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) return em; else hole_em = em; /* check to see if we've wrapped (len == -1 or similar) */ end = start + len; if (end < start) end = (u64)-1; else end -= 1; em = NULL; /* ok, we didn't find anything, lets look for delalloc */ found = count_range_bits(&inode->io_tree, &range_start, end, len, EXTENT_DELALLOC, 1); found_end = range_start + found; if (found_end < range_start) found_end = (u64)-1; /* * we didn't find anything useful, return * the original results from get_extent() */ if (range_start > end || found_end <= start) { em = hole_em; hole_em = NULL; goto out; } /* adjust the range_start to make sure it doesn't * go backwards from the start they passed in */ range_start = max(start, range_start); found = found_end - range_start; if (found > 0) { u64 hole_start = start; u64 hole_len = len; em = alloc_extent_map(); if (!em) { err = -ENOMEM; goto out; } /* * when btrfs_get_extent can't find anything it * returns one huge hole * * make sure what it found really fits our range, and * adjust to make sure it is based on the start from * the caller */ if (hole_em) { u64 calc_end = extent_map_end(hole_em); if (calc_end <= start || (hole_em->start > end)) { free_extent_map(hole_em); hole_em = NULL; } else { hole_start = max(hole_em->start, start); hole_len = calc_end - hole_start; } } em->bdev = NULL; if (hole_em && range_start > hole_start) { /* our hole starts before our delalloc, so we * have to return just the parts of the hole * that go until the delalloc starts */ em->len = min(hole_len, range_start - hole_start); em->start = hole_start; em->orig_start = hole_start; /* * don't adjust block start at all, * it is fixed at EXTENT_MAP_HOLE */ em->block_start = hole_em->block_start; em->block_len = hole_len; if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags)) set_bit(EXTENT_FLAG_PREALLOC, &em->flags); } else { em->start = range_start; em->len = found; em->orig_start = range_start; em->block_start = EXTENT_MAP_DELALLOC; em->block_len = found; } } else { return hole_em; } out: free_extent_map(hole_em); if (err) { free_extent_map(em); return ERR_PTR(err); } return em; } static struct extent_map *btrfs_create_dio_extent(struct inode *inode, const u64 start, const u64 len, const u64 orig_start, const u64 block_start, const u64 block_len, const u64 orig_block_len, const u64 ram_bytes, const int type) { struct extent_map *em = NULL; int ret; if (type != BTRFS_ORDERED_NOCOW) { em = create_io_em(inode, start, len, orig_start, block_start, block_len, orig_block_len, ram_bytes, BTRFS_COMPRESS_NONE, /* compress_type */ type); if (IS_ERR(em)) goto out; } ret = btrfs_add_ordered_extent_dio(inode, start, block_start, len, block_len, type); if (ret) { if (em) { free_extent_map(em); btrfs_drop_extent_cache(BTRFS_I(inode), start, start + len - 1, 0); } em = ERR_PTR(ret); } out: return em; } static struct extent_map *btrfs_new_extent_direct(struct inode *inode, u64 start, u64 len) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_map *em; struct btrfs_key ins; u64 alloc_hint; int ret; alloc_hint = get_extent_allocation_hint(inode, start, len); ret = btrfs_reserve_extent(root, len, len, fs_info->sectorsize, 0, alloc_hint, &ins, 1, 1); if (ret) return ERR_PTR(ret); em = btrfs_create_dio_extent(inode, start, ins.offset, start, ins.objectid, ins.offset, ins.offset, ins.offset, BTRFS_ORDERED_REGULAR); btrfs_dec_block_group_reservations(fs_info, ins.objectid); if (IS_ERR(em)) btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); return em; } /* * returns 1 when the nocow is safe, < 1 on error, 0 if the * block must be cow'd */ noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len, u64 *orig_start, u64 *orig_block_len, u64 *ram_bytes) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_path *path; int ret; struct extent_buffer *leaf; struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_file_extent_item *fi; struct btrfs_key key; u64 disk_bytenr; u64 backref_offset; u64 extent_end; u64 num_bytes; int slot; int found_type; bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW); path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(BTRFS_I(inode)), offset, 0); if (ret < 0) goto out; slot = path->slots[0]; if (ret == 1) { if (slot == 0) { /* can't find the item, must cow */ ret = 0; goto out; } slot--; } ret = 0; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, slot); if (key.objectid != btrfs_ino(BTRFS_I(inode)) || key.type != BTRFS_EXTENT_DATA_KEY) { /* not our file or wrong item type, must cow */ goto out; } if (key.offset > offset) { /* Wrong offset, must cow */ goto out; } fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); found_type = btrfs_file_extent_type(leaf, fi); if (found_type != BTRFS_FILE_EXTENT_REG && found_type != BTRFS_FILE_EXTENT_PREALLOC) { /* not a regular extent, must cow */ goto out; } if (!nocow && found_type == BTRFS_FILE_EXTENT_REG) goto out; extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); if (extent_end <= offset) goto out; disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); if (disk_bytenr == 0) goto out; if (btrfs_file_extent_compression(leaf, fi) || btrfs_file_extent_encryption(leaf, fi) || btrfs_file_extent_other_encoding(leaf, fi)) goto out; /* * Do the same check as in btrfs_cross_ref_exist but without the * unnecessary search. */ if (btrfs_file_extent_generation(leaf, fi) <= btrfs_root_last_snapshot(&root->root_item)) goto out; backref_offset = btrfs_file_extent_offset(leaf, fi); if (orig_start) { *orig_start = key.offset - backref_offset; *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi); *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); } if (btrfs_extent_readonly(fs_info, disk_bytenr)) goto out; num_bytes = min(offset + *len, extent_end) - offset; if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) { u64 range_end; range_end = round_up(offset + num_bytes, root->fs_info->sectorsize) - 1; ret = test_range_bit(io_tree, offset, range_end, EXTENT_DELALLOC, 0, NULL); if (ret) { ret = -EAGAIN; goto out; } } btrfs_release_path(path); /* * look for other files referencing this extent, if we * find any we must cow */ ret = btrfs_cross_ref_exist(root, btrfs_ino(BTRFS_I(inode)), key.offset - backref_offset, disk_bytenr); if (ret) { ret = 0; goto out; } /* * adjust disk_bytenr and num_bytes to cover just the bytes * in this extent we are about to write. If there * are any csums in that range we have to cow in order * to keep the csums correct */ disk_bytenr += backref_offset; disk_bytenr += offset - key.offset; if (csum_exist_in_range(fs_info, disk_bytenr, num_bytes)) goto out; /* * all of the above have passed, it is safe to overwrite this extent * without cow */ *len = num_bytes; ret = 1; out: btrfs_free_path(path); return ret; } static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend, struct extent_state **cached_state, int writing) { struct btrfs_ordered_extent *ordered; int ret = 0; while (1) { lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, cached_state); /* * We're concerned with the entire range that we're going to be * doing DIO to, so we need to make sure there's no ordered * extents in this range. */ ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), lockstart, lockend - lockstart + 1); /* * We need to make sure there are no buffered pages in this * range either, we could have raced between the invalidate in * generic_file_direct_write and locking the extent. The * invalidate needs to happen so that reads after a write do not * get stale data. */ if (!ordered && (!writing || !filemap_range_has_page(inode->i_mapping, lockstart, lockend))) break; unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, cached_state); if (ordered) { /* * If we are doing a DIO read and the ordered extent we * found is for a buffered write, we can not wait for it * to complete and retry, because if we do so we can * deadlock with concurrent buffered writes on page * locks. This happens only if our DIO read covers more * than one extent map, if at this point has already * created an ordered extent for a previous extent map * and locked its range in the inode's io tree, and a * concurrent write against that previous extent map's * range and this range started (we unlock the ranges * in the io tree only when the bios complete and * buffered writes always lock pages before attempting * to lock range in the io tree). */ if (writing || test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) btrfs_start_ordered_extent(inode, ordered, 1); else ret = -ENOTBLK; btrfs_put_ordered_extent(ordered); } else { /* * We could trigger writeback for this range (and wait * for it to complete) and then invalidate the pages for * this range (through invalidate_inode_pages2_range()), * but that can lead us to a deadlock with a concurrent * call to readpages() (a buffered read or a defrag call * triggered a readahead) on a page lock due to an * ordered dio extent we created before but did not have * yet a corresponding bio submitted (whence it can not * complete), which makes readpages() wait for that * ordered extent to complete while holding a lock on * that page. */ ret = -ENOTBLK; } if (ret) break; cond_resched(); } return ret; } /* The callers of this must take lock_extent() */ static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len, u64 orig_start, u64 block_start, u64 block_len, u64 orig_block_len, u64 ram_bytes, int compress_type, int type) { struct extent_map_tree *em_tree; struct extent_map *em; struct btrfs_root *root = BTRFS_I(inode)->root; int ret; ASSERT(type == BTRFS_ORDERED_PREALLOC || type == BTRFS_ORDERED_COMPRESSED || type == BTRFS_ORDERED_NOCOW || type == BTRFS_ORDERED_REGULAR); em_tree = &BTRFS_I(inode)->extent_tree; em = alloc_extent_map(); if (!em) return ERR_PTR(-ENOMEM); em->start = start; em->orig_start = orig_start; em->len = len; em->block_len = block_len; em->block_start = block_start; em->bdev = root->fs_info->fs_devices->latest_bdev; em->orig_block_len = orig_block_len; em->ram_bytes = ram_bytes; em->generation = -1; set_bit(EXTENT_FLAG_PINNED, &em->flags); if (type == BTRFS_ORDERED_PREALLOC) { set_bit(EXTENT_FLAG_FILLING, &em->flags); } else if (type == BTRFS_ORDERED_COMPRESSED) { set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); em->compress_type = compress_type; } do { btrfs_drop_extent_cache(BTRFS_I(inode), em->start, em->start + em->len - 1, 0); write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em, 1); write_unlock(&em_tree->lock); /* * The caller has taken lock_extent(), who could race with us * to add em? */ } while (ret == -EEXIST); if (ret) { free_extent_map(em); return ERR_PTR(ret); } /* em got 2 refs now, callers needs to do free_extent_map once. */ return em; } static int btrfs_get_blocks_direct_read(struct extent_map *em, struct buffer_head *bh_result, struct inode *inode, u64 start, u64 len) { if (em->block_start == EXTENT_MAP_HOLE || test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) return -ENOENT; len = min(len, em->len - (start - em->start)); bh_result->b_blocknr = (em->block_start + (start - em->start)) >> inode->i_blkbits; bh_result->b_size = len; bh_result->b_bdev = em->bdev; set_buffer_mapped(bh_result); return 0; } static int btrfs_get_blocks_direct_write(struct extent_map **map, struct buffer_head *bh_result, struct inode *inode, struct btrfs_dio_data *dio_data, u64 start, u64 len) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct extent_map *em = *map; int ret = 0; /* * We don't allocate a new extent in the following cases * * 1) The inode is marked as NODATACOW. In this case we'll just use the * existing extent. * 2) The extent is marked as PREALLOC. We're good to go here and can * just use the extent. * */ if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) || ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && em->block_start != EXTENT_MAP_HOLE)) { int type; u64 block_start, orig_start, orig_block_len, ram_bytes; if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) type = BTRFS_ORDERED_PREALLOC; else type = BTRFS_ORDERED_NOCOW; len = min(len, em->len - (start - em->start)); block_start = em->block_start + (start - em->start); if (can_nocow_extent(inode, start, &len, &orig_start, &orig_block_len, &ram_bytes) == 1 && btrfs_inc_nocow_writers(fs_info, block_start)) { struct extent_map *em2; em2 = btrfs_create_dio_extent(inode, start, len, orig_start, block_start, len, orig_block_len, ram_bytes, type); btrfs_dec_nocow_writers(fs_info, block_start); if (type == BTRFS_ORDERED_PREALLOC) { free_extent_map(em); *map = em = em2; } if (em2 && IS_ERR(em2)) { ret = PTR_ERR(em2); goto out; } /* * For inode marked NODATACOW or extent marked PREALLOC, * use the existing or preallocated extent, so does not * need to adjust btrfs_space_info's bytes_may_use. */ btrfs_free_reserved_data_space_noquota(inode, start, len); goto skip_cow; } } /* this will cow the extent */ len = bh_result->b_size; free_extent_map(em); *map = em = btrfs_new_extent_direct(inode, start, len); if (IS_ERR(em)) { ret = PTR_ERR(em); goto out; } len = min(len, em->len - (start - em->start)); skip_cow: bh_result->b_blocknr = (em->block_start + (start - em->start)) >> inode->i_blkbits; bh_result->b_size = len; bh_result->b_bdev = em->bdev; set_buffer_mapped(bh_result); if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) set_buffer_new(bh_result); /* * Need to update the i_size under the extent lock so buffered * readers will get the updated i_size when we unlock. */ if (!dio_data->overwrite && start + len > i_size_read(inode)) i_size_write(inode, start + len); WARN_ON(dio_data->reserve < len); dio_data->reserve -= len; dio_data->unsubmitted_oe_range_end = start + len; current->journal_info = dio_data; out: return ret; } static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct extent_map *em; struct extent_state *cached_state = NULL; struct btrfs_dio_data *dio_data = NULL; u64 start = iblock << inode->i_blkbits; u64 lockstart, lockend; u64 len = bh_result->b_size; int unlock_bits = EXTENT_LOCKED; int ret = 0; if (create) unlock_bits |= EXTENT_DIRTY; else len = min_t(u64, len, fs_info->sectorsize); lockstart = start; lockend = start + len - 1; if (current->journal_info) { /* * Need to pull our outstanding extents and set journal_info to NULL so * that anything that needs to check if there's a transaction doesn't get * confused. */ dio_data = current->journal_info; current->journal_info = NULL; } /* * If this errors out it's because we couldn't invalidate pagecache for * this range and we need to fallback to buffered. */ if (lock_extent_direct(inode, lockstart, lockend, &cached_state, create)) { ret = -ENOTBLK; goto err; } em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0); if (IS_ERR(em)) { ret = PTR_ERR(em); goto unlock_err; } /* * Ok for INLINE and COMPRESSED extents we need to fallback on buffered * io. INLINE is special, and we could probably kludge it in here, but * it's still buffered so for safety lets just fall back to the generic * buffered path. * * For COMPRESSED we _have_ to read the entire extent in so we can * decompress it, so there will be buffering required no matter what we * do, so go ahead and fallback to buffered. * * We return -ENOTBLK because that's what makes DIO go ahead and go back * to buffered IO. Don't blame me, this is the price we pay for using * the generic code. */ if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) || em->block_start == EXTENT_MAP_INLINE) { free_extent_map(em); ret = -ENOTBLK; goto unlock_err; } if (create) { ret = btrfs_get_blocks_direct_write(&em, bh_result, inode, dio_data, start, len); if (ret < 0) goto unlock_err; /* clear and unlock the entire range */ clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, unlock_bits, 1, 0, &cached_state); } else { ret = btrfs_get_blocks_direct_read(em, bh_result, inode, start, len); /* Can be negative only if we read from a hole */ if (ret < 0) { ret = 0; free_extent_map(em); goto unlock_err; } /* * We need to unlock only the end area that we aren't using. * The rest is going to be unlocked by the endio routine. */ lockstart = start + bh_result->b_size; if (lockstart < lockend) { clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, unlock_bits, 1, 0, &cached_state); } else { free_extent_state(cached_state); } } free_extent_map(em); return 0; unlock_err: clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, unlock_bits, 1, 0, &cached_state); err: if (dio_data) current->journal_info = dio_data; return ret; } static inline blk_status_t submit_dio_repair_bio(struct inode *inode, struct bio *bio, int mirror_num) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); blk_status_t ret; BUG_ON(bio_op(bio) == REQ_OP_WRITE); ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DIO_REPAIR); if (ret) return ret; ret = btrfs_map_bio(fs_info, bio, mirror_num, 0); return ret; } static int btrfs_check_dio_repairable(struct inode *inode, struct bio *failed_bio, struct io_failure_record *failrec, int failed_mirror) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); int num_copies; num_copies = btrfs_num_copies(fs_info, failrec->logical, failrec->len); if (num_copies == 1) { /* * we only have a single copy of the data, so don't bother with * all the retry and error correction code that follows. no * matter what the error is, it is very likely to persist. */ btrfs_debug(fs_info, "Check DIO Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d", num_copies, failrec->this_mirror, failed_mirror); return 0; } failrec->failed_mirror = failed_mirror; failrec->this_mirror++; if (failrec->this_mirror == failed_mirror) failrec->this_mirror++; if (failrec->this_mirror > num_copies) { btrfs_debug(fs_info, "Check DIO Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d", num_copies, failrec->this_mirror, failed_mirror); return 0; } return 1; } static blk_status_t dio_read_error(struct inode *inode, struct bio *failed_bio, struct page *page, unsigned int pgoff, u64 start, u64 end, int failed_mirror, bio_end_io_t *repair_endio, void *repair_arg) { struct io_failure_record *failrec; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree; struct bio *bio; int isector; unsigned int read_mode = 0; int segs; int ret; blk_status_t status; struct bio_vec bvec; BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE); ret = btrfs_get_io_failure_record(inode, start, end, &failrec); if (ret) return errno_to_blk_status(ret); ret = btrfs_check_dio_repairable(inode, failed_bio, failrec, failed_mirror); if (!ret) { free_io_failure(failure_tree, io_tree, failrec); return BLK_STS_IOERR; } segs = bio_segments(failed_bio); bio_get_first_bvec(failed_bio, &bvec); if (segs > 1 || (bvec.bv_len > btrfs_inode_sectorsize(inode))) read_mode |= REQ_FAILFAST_DEV; isector = start - btrfs_io_bio(failed_bio)->logical; isector >>= inode->i_sb->s_blocksize_bits; bio = btrfs_create_repair_bio(inode, failed_bio, failrec, page, pgoff, isector, repair_endio, repair_arg); bio->bi_opf = REQ_OP_READ | read_mode; btrfs_debug(BTRFS_I(inode)->root->fs_info, "repair DIO read error: submitting new dio read[%#x] to this_mirror=%d, in_validation=%d", read_mode, failrec->this_mirror, failrec->in_validation); status = submit_dio_repair_bio(inode, bio, failrec->this_mirror); if (status) { free_io_failure(failure_tree, io_tree, failrec); bio_put(bio); } return status; } struct btrfs_retry_complete { struct completion done; struct inode *inode; u64 start; int uptodate; }; static void btrfs_retry_endio_nocsum(struct bio *bio) { struct btrfs_retry_complete *done = bio->bi_private; struct inode *inode = done->inode; struct bio_vec *bvec; struct extent_io_tree *io_tree, *failure_tree; int i; if (bio->bi_status) goto end; ASSERT(bio->bi_vcnt == 1); io_tree = &BTRFS_I(inode)->io_tree; failure_tree = &BTRFS_I(inode)->io_failure_tree; ASSERT(bio_first_bvec_all(bio)->bv_len == btrfs_inode_sectorsize(inode)); done->uptodate = 1; ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, i) clean_io_failure(BTRFS_I(inode)->root->fs_info, failure_tree, io_tree, done->start, bvec->bv_page, btrfs_ino(BTRFS_I(inode)), 0); end: complete(&done->done); bio_put(bio); } static blk_status_t __btrfs_correct_data_nocsum(struct inode *inode, struct btrfs_io_bio *io_bio) { struct btrfs_fs_info *fs_info; struct bio_vec bvec; struct bvec_iter iter; struct btrfs_retry_complete done; u64 start; unsigned int pgoff; u32 sectorsize; int nr_sectors; blk_status_t ret; blk_status_t err = BLK_STS_OK; fs_info = BTRFS_I(inode)->root->fs_info; sectorsize = fs_info->sectorsize; start = io_bio->logical; done.inode = inode; io_bio->bio.bi_iter = io_bio->iter; bio_for_each_segment(bvec, &io_bio->bio, iter) { nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len); pgoff = bvec.bv_offset; next_block_or_try_again: done.uptodate = 0; done.start = start; init_completion(&done.done); ret = dio_read_error(inode, &io_bio->bio, bvec.bv_page, pgoff, start, start + sectorsize - 1, io_bio->mirror_num, btrfs_retry_endio_nocsum, &done); if (ret) { err = ret; goto next; } wait_for_completion_io(&done.done); if (!done.uptodate) { /* We might have another mirror, so try again */ goto next_block_or_try_again; } next: start += sectorsize; nr_sectors--; if (nr_sectors) { pgoff += sectorsize; ASSERT(pgoff < PAGE_SIZE); goto next_block_or_try_again; } } return err; } static void btrfs_retry_endio(struct bio *bio) { struct btrfs_retry_complete *done = bio->bi_private; struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); struct extent_io_tree *io_tree, *failure_tree; struct inode *inode = done->inode; struct bio_vec *bvec; int uptodate; int ret; int i; if (bio->bi_status) goto end; uptodate = 1; ASSERT(bio->bi_vcnt == 1); ASSERT(bio_first_bvec_all(bio)->bv_len == btrfs_inode_sectorsize(done->inode)); io_tree = &BTRFS_I(inode)->io_tree; failure_tree = &BTRFS_I(inode)->io_failure_tree; ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, i) { ret = __readpage_endio_check(inode, io_bio, i, bvec->bv_page, bvec->bv_offset, done->start, bvec->bv_len); if (!ret) clean_io_failure(BTRFS_I(inode)->root->fs_info, failure_tree, io_tree, done->start, bvec->bv_page, btrfs_ino(BTRFS_I(inode)), bvec->bv_offset); else uptodate = 0; } done->uptodate = uptodate; end: complete(&done->done); bio_put(bio); } static blk_status_t __btrfs_subio_endio_read(struct inode *inode, struct btrfs_io_bio *io_bio, blk_status_t err) { struct btrfs_fs_info *fs_info; struct bio_vec bvec; struct bvec_iter iter; struct btrfs_retry_complete done; u64 start; u64 offset = 0; u32 sectorsize; int nr_sectors; unsigned int pgoff; int csum_pos; bool uptodate = (err == 0); int ret; blk_status_t status; fs_info = BTRFS_I(inode)->root->fs_info; sectorsize = fs_info->sectorsize; err = BLK_STS_OK; start = io_bio->logical; done.inode = inode; io_bio->bio.bi_iter = io_bio->iter; bio_for_each_segment(bvec, &io_bio->bio, iter) { nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len); pgoff = bvec.bv_offset; next_block: if (uptodate) { csum_pos = BTRFS_BYTES_TO_BLKS(fs_info, offset); ret = __readpage_endio_check(inode, io_bio, csum_pos, bvec.bv_page, pgoff, start, sectorsize); if (likely(!ret)) goto next; } try_again: done.uptodate = 0; done.start = start; init_completion(&done.done); status = dio_read_error(inode, &io_bio->bio, bvec.bv_page, pgoff, start, start + sectorsize - 1, io_bio->mirror_num, btrfs_retry_endio, &done); if (status) { err = status; goto next; } wait_for_completion_io(&done.done); if (!done.uptodate) { /* We might have another mirror, so try again */ goto try_again; } next: offset += sectorsize; start += sectorsize; ASSERT(nr_sectors); nr_sectors--; if (nr_sectors) { pgoff += sectorsize; ASSERT(pgoff < PAGE_SIZE); goto next_block; } } return err; } static blk_status_t btrfs_subio_endio_read(struct inode *inode, struct btrfs_io_bio *io_bio, blk_status_t err) { bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; if (skip_csum) { if (unlikely(err)) return __btrfs_correct_data_nocsum(inode, io_bio); else return BLK_STS_OK; } else { return __btrfs_subio_endio_read(inode, io_bio, err); } } static void btrfs_endio_direct_read(struct bio *bio) { struct btrfs_dio_private *dip = bio->bi_private; struct inode *inode = dip->inode; struct bio *dio_bio; struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); blk_status_t err = bio->bi_status; if (dip->flags & BTRFS_DIO_ORIG_BIO_SUBMITTED) err = btrfs_subio_endio_read(inode, io_bio, err); unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset, dip->logical_offset + dip->bytes - 1); dio_bio = dip->dio_bio; kfree(dip); dio_bio->bi_status = err; dio_end_io(dio_bio); btrfs_io_bio_free_csum(io_bio); bio_put(bio); } static void __endio_write_update_ordered(struct inode *inode, const u64 offset, const u64 bytes, const bool uptodate) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_ordered_extent *ordered = NULL; struct btrfs_workqueue *wq; btrfs_work_func_t func; u64 ordered_offset = offset; u64 ordered_bytes = bytes; u64 last_offset; if (btrfs_is_free_space_inode(BTRFS_I(inode))) { wq = fs_info->endio_freespace_worker; func = btrfs_freespace_write_helper; } else { wq = fs_info->endio_write_workers; func = btrfs_endio_write_helper; } while (ordered_offset < offset + bytes) { last_offset = ordered_offset; if (btrfs_dec_test_first_ordered_pending(inode, &ordered, &ordered_offset, ordered_bytes, uptodate)) { btrfs_init_work(&ordered->work, func, finish_ordered_fn, NULL, NULL); btrfs_queue_work(wq, &ordered->work); } /* * If btrfs_dec_test_ordered_pending does not find any ordered * extent in the range, we can exit. */ if (ordered_offset == last_offset) return; /* * Our bio might span multiple ordered extents. In this case * we keep going until we have accounted the whole dio. */ if (ordered_offset < offset + bytes) { ordered_bytes = offset + bytes - ordered_offset; ordered = NULL; } } } static void btrfs_endio_direct_write(struct bio *bio) { struct btrfs_dio_private *dip = bio->bi_private; struct bio *dio_bio = dip->dio_bio; __endio_write_update_ordered(dip->inode, dip->logical_offset, dip->bytes, !bio->bi_status); kfree(dip); dio_bio->bi_status = bio->bi_status; dio_end_io(dio_bio); bio_put(bio); } static blk_status_t btrfs_submit_bio_start_direct_io(void *private_data, struct bio *bio, u64 offset) { struct inode *inode = private_data; blk_status_t ret; ret = btrfs_csum_one_bio(inode, bio, offset, 1); BUG_ON(ret); /* -ENOMEM */ return 0; } static void btrfs_end_dio_bio(struct bio *bio) { struct btrfs_dio_private *dip = bio->bi_private; blk_status_t err = bio->bi_status; if (err) btrfs_warn(BTRFS_I(dip->inode)->root->fs_info, "direct IO failed ino %llu rw %d,%u sector %#Lx len %u err no %d", btrfs_ino(BTRFS_I(dip->inode)), bio_op(bio), bio->bi_opf, (unsigned long long)bio->bi_iter.bi_sector, bio->bi_iter.bi_size, err); if (dip->subio_endio) err = dip->subio_endio(dip->inode, btrfs_io_bio(bio), err); if (err) { /* * We want to perceive the errors flag being set before * decrementing the reference count. We don't need a barrier * since atomic operations with a return value are fully * ordered as per atomic_t.txt */ dip->errors = 1; } /* if there are more bios still pending for this dio, just exit */ if (!atomic_dec_and_test(&dip->pending_bios)) goto out; if (dip->errors) { bio_io_error(dip->orig_bio); } else { dip->dio_bio->bi_status = BLK_STS_OK; bio_endio(dip->orig_bio); } out: bio_put(bio); } static inline blk_status_t btrfs_lookup_and_bind_dio_csum(struct inode *inode, struct btrfs_dio_private *dip, struct bio *bio, u64 file_offset) { struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); struct btrfs_io_bio *orig_io_bio = btrfs_io_bio(dip->orig_bio); blk_status_t ret; /* * We load all the csum data we need when we submit * the first bio to reduce the csum tree search and * contention. */ if (dip->logical_offset == file_offset) { ret = btrfs_lookup_bio_sums_dio(inode, dip->orig_bio, file_offset); if (ret) return ret; } if (bio == dip->orig_bio) return 0; file_offset -= dip->logical_offset; file_offset >>= inode->i_sb->s_blocksize_bits; io_bio->csum = (u8 *)(((u32 *)orig_io_bio->csum) + file_offset); return 0; } static inline blk_status_t btrfs_submit_dio_bio(struct bio *bio, struct inode *inode, u64 file_offset, int async_submit) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_dio_private *dip = bio->bi_private; bool write = bio_op(bio) == REQ_OP_WRITE; blk_status_t ret; /* Check btrfs_submit_bio_hook() for rules about async submit. */ if (async_submit) async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers); if (!write) { ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA); if (ret) goto err; } if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) goto map; if (write && async_submit) { ret = btrfs_wq_submit_bio(fs_info, bio, 0, 0, file_offset, inode, btrfs_submit_bio_start_direct_io); goto err; } else if (write) { /* * If we aren't doing async submit, calculate the csum of the * bio now. */ ret = btrfs_csum_one_bio(inode, bio, file_offset, 1); if (ret) goto err; } else { ret = btrfs_lookup_and_bind_dio_csum(inode, dip, bio, file_offset); if (ret) goto err; } map: ret = btrfs_map_bio(fs_info, bio, 0, 0); err: return ret; } static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip) { struct inode *inode = dip->inode; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct bio *bio; struct bio *orig_bio = dip->orig_bio; u64 start_sector = orig_bio->bi_iter.bi_sector; u64 file_offset = dip->logical_offset; u64 map_length; int async_submit = 0; u64 submit_len; int clone_offset = 0; int clone_len; int ret; blk_status_t status; map_length = orig_bio->bi_iter.bi_size; submit_len = map_length; ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), start_sector << 9, &map_length, NULL, 0); if (ret) return -EIO; if (map_length >= submit_len) { bio = orig_bio; dip->flags |= BTRFS_DIO_ORIG_BIO_SUBMITTED; goto submit; } /* async crcs make it difficult to collect full stripe writes. */ if (btrfs_data_alloc_profile(fs_info) & BTRFS_BLOCK_GROUP_RAID56_MASK) async_submit = 0; else async_submit = 1; /* bio split */ ASSERT(map_length <= INT_MAX); atomic_inc(&dip->pending_bios); do { clone_len = min_t(int, submit_len, map_length); /* * This will never fail as it's passing GPF_NOFS and * the allocation is backed by btrfs_bioset. */ bio = btrfs_bio_clone_partial(orig_bio, clone_offset, clone_len); bio->bi_private = dip; bio->bi_end_io = btrfs_end_dio_bio; btrfs_io_bio(bio)->logical = file_offset; ASSERT(submit_len >= clone_len); submit_len -= clone_len; if (submit_len == 0) break; /* * Increase the count before we submit the bio so we know * the end IO handler won't happen before we increase the * count. Otherwise, the dip might get freed before we're * done setting it up. */ atomic_inc(&dip->pending_bios); status = btrfs_submit_dio_bio(bio, inode, file_offset, async_submit); if (status) { bio_put(bio); atomic_dec(&dip->pending_bios); goto out_err; } clone_offset += clone_len; start_sector += clone_len >> 9; file_offset += clone_len; map_length = submit_len; ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), start_sector << 9, &map_length, NULL, 0); if (ret) goto out_err; } while (submit_len > 0); submit: status = btrfs_submit_dio_bio(bio, inode, file_offset, async_submit); if (!status) return 0; bio_put(bio); out_err: dip->errors = 1; /* * Before atomic variable goto zero, we must make sure dip->errors is * perceived to be set. This ordering is ensured by the fact that an * atomic operations with a return value are fully ordered as per * atomic_t.txt */ if (atomic_dec_and_test(&dip->pending_bios)) bio_io_error(dip->orig_bio); /* bio_end_io() will handle error, so we needn't return it */ return 0; } static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode, loff_t file_offset) { struct btrfs_dio_private *dip = NULL; struct bio *bio = NULL; struct btrfs_io_bio *io_bio; bool write = (bio_op(dio_bio) == REQ_OP_WRITE); int ret = 0; bio = btrfs_bio_clone(dio_bio); dip = kzalloc(sizeof(*dip), GFP_NOFS); if (!dip) { ret = -ENOMEM; goto free_ordered; } dip->private = dio_bio->bi_private; dip->inode = inode; dip->logical_offset = file_offset; dip->bytes = dio_bio->bi_iter.bi_size; dip->disk_bytenr = (u64)dio_bio->bi_iter.bi_sector << 9; bio->bi_private = dip; dip->orig_bio = bio; dip->dio_bio = dio_bio; atomic_set(&dip->pending_bios, 0); io_bio = btrfs_io_bio(bio); io_bio->logical = file_offset; if (write) { bio->bi_end_io = btrfs_endio_direct_write; } else { bio->bi_end_io = btrfs_endio_direct_read; dip->subio_endio = btrfs_subio_endio_read; } /* * Reset the range for unsubmitted ordered extents (to a 0 length range) * even if we fail to submit a bio, because in such case we do the * corresponding error handling below and it must not be done a second * time by btrfs_direct_IO(). */ if (write) { struct btrfs_dio_data *dio_data = current->journal_info; dio_data->unsubmitted_oe_range_end = dip->logical_offset + dip->bytes; dio_data->unsubmitted_oe_range_start = dio_data->unsubmitted_oe_range_end; } ret = btrfs_submit_direct_hook(dip); if (!ret) return; btrfs_io_bio_free_csum(io_bio); free_ordered: /* * If we arrived here it means either we failed to submit the dip * or we either failed to clone the dio_bio or failed to allocate the * dip. If we cloned the dio_bio and allocated the dip, we can just * call bio_endio against our io_bio so that we get proper resource * cleanup if we fail to submit the dip, otherwise, we must do the * same as btrfs_endio_direct_[write|read] because we can't call these * callbacks - they require an allocated dip and a clone of dio_bio. */ if (bio && dip) { bio_io_error(bio); /* * The end io callbacks free our dip, do the final put on bio * and all the cleanup and final put for dio_bio (through * dio_end_io()). */ dip = NULL; bio = NULL; } else { if (write) __endio_write_update_ordered(inode, file_offset, dio_bio->bi_iter.bi_size, false); else unlock_extent(&BTRFS_I(inode)->io_tree, file_offset, file_offset + dio_bio->bi_iter.bi_size - 1); dio_bio->bi_status = BLK_STS_IOERR; /* * Releases and cleans up our dio_bio, no need to bio_put() * nor bio_endio()/bio_io_error() against dio_bio. */ dio_end_io(dio_bio); } if (bio) bio_put(bio); kfree(dip); } static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info, const struct iov_iter *iter, loff_t offset) { int seg; int i; unsigned int blocksize_mask = fs_info->sectorsize - 1; ssize_t retval = -EINVAL; if (offset & blocksize_mask) goto out; if (iov_iter_alignment(iter) & blocksize_mask) goto out; /* If this is a write we don't need to check anymore */ if (iov_iter_rw(iter) != READ || !iter_is_iovec(iter)) return 0; /* * Check to make sure we don't have duplicate iov_base's in this * iovec, if so return EINVAL, otherwise we'll get csum errors * when reading back. */ for (seg = 0; seg < iter->nr_segs; seg++) { for (i = seg + 1; i < iter->nr_segs; i++) { if (iter->iov[seg].iov_base == iter->iov[i].iov_base) goto out; } } retval = 0; out: return retval; } static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) { struct file *file = iocb->ki_filp; struct inode *inode = file->f_mapping->host; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_dio_data dio_data = { 0 }; struct extent_changeset *data_reserved = NULL; loff_t offset = iocb->ki_pos; size_t count = 0; int flags = 0; bool wakeup = true; bool relock = false; ssize_t ret; if (check_direct_IO(fs_info, iter, offset)) return 0; inode_dio_begin(inode); /* * The generic stuff only does filemap_write_and_wait_range, which * isn't enough if we've written compressed pages to this area, so * we need to flush the dirty pages again to make absolutely sure * that any outstanding dirty pages are on disk. */ count = iov_iter_count(iter); if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &BTRFS_I(inode)->runtime_flags)) filemap_fdatawrite_range(inode->i_mapping, offset, offset + count - 1); if (iov_iter_rw(iter) == WRITE) { /* * If the write DIO is beyond the EOF, we need update * the isize, but it is protected by i_mutex. So we can * not unlock the i_mutex at this case. */ if (offset + count <= inode->i_size) { dio_data.overwrite = 1; inode_unlock(inode); relock = true; } else if (iocb->ki_flags & IOCB_NOWAIT) { ret = -EAGAIN; goto out; } ret = btrfs_delalloc_reserve_space(inode, &data_reserved, offset, count); if (ret) goto out; /* * We need to know how many extents we reserved so that we can * do the accounting properly if we go over the number we * originally calculated. Abuse current->journal_info for this. */ dio_data.reserve = round_up(count, fs_info->sectorsize); dio_data.unsubmitted_oe_range_start = (u64)offset; dio_data.unsubmitted_oe_range_end = (u64)offset; current->journal_info = &dio_data; down_read(&BTRFS_I(inode)->dio_sem); } else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK, &BTRFS_I(inode)->runtime_flags)) { inode_dio_end(inode); flags = DIO_LOCKING | DIO_SKIP_HOLES; wakeup = false; } ret = __blockdev_direct_IO(iocb, inode, fs_info->fs_devices->latest_bdev, iter, btrfs_get_blocks_direct, NULL, btrfs_submit_direct, flags); if (iov_iter_rw(iter) == WRITE) { up_read(&BTRFS_I(inode)->dio_sem); current->journal_info = NULL; if (ret < 0 && ret != -EIOCBQUEUED) { if (dio_data.reserve) btrfs_delalloc_release_space(inode, data_reserved, offset, dio_data.reserve, true); /* * On error we might have left some ordered extents * without submitting corresponding bios for them, so * cleanup them up to avoid other tasks getting them * and waiting for them to complete forever. */ if (dio_data.unsubmitted_oe_range_start < dio_data.unsubmitted_oe_range_end) __endio_write_update_ordered(inode, dio_data.unsubmitted_oe_range_start, dio_data.unsubmitted_oe_range_end - dio_data.unsubmitted_oe_range_start, false); } else if (ret >= 0 && (size_t)ret < count) btrfs_delalloc_release_space(inode, data_reserved, offset, count - (size_t)ret, true); btrfs_delalloc_release_extents(BTRFS_I(inode), count, false); } out: if (wakeup) inode_dio_end(inode); if (relock) inode_lock(inode); extent_changeset_free(data_reserved); return ret; } #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC) static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, __u64 start, __u64 len) { int ret; ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS); if (ret) return ret; return extent_fiemap(inode, fieinfo, start, len); } int btrfs_readpage(struct file *file, struct page *page) { struct extent_io_tree *tree; tree = &BTRFS_I(page->mapping->host)->io_tree; return extent_read_full_page(tree, page, btrfs_get_extent, 0); } static int btrfs_writepage(struct page *page, struct writeback_control *wbc) { struct inode *inode = page->mapping->host; int ret; if (current->flags & PF_MEMALLOC) { redirty_page_for_writepage(wbc, page); unlock_page(page); return 0; } /* * If we are under memory pressure we will call this directly from the * VM, we need to make sure we have the inode referenced for the ordered * extent. If not just return like we didn't do anything. */ if (!igrab(inode)) { redirty_page_for_writepage(wbc, page); return AOP_WRITEPAGE_ACTIVATE; } ret = extent_write_full_page(page, wbc); btrfs_add_delayed_iput(inode); return ret; } static int btrfs_writepages(struct address_space *mapping, struct writeback_control *wbc) { return extent_writepages(mapping, wbc); } static int btrfs_readpages(struct file *file, struct address_space *mapping, struct list_head *pages, unsigned nr_pages) { return extent_readpages(mapping, pages, nr_pages); } static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) { int ret = try_release_extent_mapping(page, gfp_flags); if (ret == 1) { ClearPagePrivate(page); set_page_private(page, 0); put_page(page); } return ret; } static int btrfs_releasepage(struct page *page, gfp_t gfp_flags) { if (PageWriteback(page) || PageDirty(page)) return 0; return __btrfs_releasepage(page, gfp_flags); } static void btrfs_invalidatepage(struct page *page, unsigned int offset, unsigned int length) { struct inode *inode = page->mapping->host; struct extent_io_tree *tree; struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; u64 page_start = page_offset(page); u64 page_end = page_start + PAGE_SIZE - 1; u64 start; u64 end; int inode_evicting = inode->i_state & I_FREEING; /* * we have the page locked, so new writeback can't start, * and the dirty bit won't be cleared while we are here. * * Wait for IO on this page so that we can safely clear * the PagePrivate2 bit and do ordered accounting */ wait_on_page_writeback(page); tree = &BTRFS_I(inode)->io_tree; if (offset) { btrfs_releasepage(page, GFP_NOFS); return; } if (!inode_evicting) lock_extent_bits(tree, page_start, page_end, &cached_state); again: start = page_start; ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start, page_end - start + 1); if (ordered) { end = min(page_end, ordered->file_offset + ordered->len - 1); /* * IO on this page will never be started, so we need * to account for any ordered extents now */ if (!inode_evicting) clear_extent_bit(tree, start, end, EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_LOCKED | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 0, &cached_state); /* * whoever cleared the private bit is responsible * for the finish_ordered_io */ if (TestClearPagePrivate2(page)) { struct btrfs_ordered_inode_tree *tree; u64 new_len; tree = &BTRFS_I(inode)->ordered_tree; spin_lock_irq(&tree->lock); set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags); new_len = start - ordered->file_offset; if (new_len < ordered->truncated_len) ordered->truncated_len = new_len; spin_unlock_irq(&tree->lock); if (btrfs_dec_test_ordered_pending(inode, &ordered, start, end - start + 1, 1)) btrfs_finish_ordered_io(ordered); } btrfs_put_ordered_extent(ordered); if (!inode_evicting) { cached_state = NULL; lock_extent_bits(tree, start, end, &cached_state); } start = end + 1; if (start < page_end) goto again; } /* * Qgroup reserved space handler * Page here will be either * 1) Already written to disk * In this case, its reserved space is released from data rsv map * and will be freed by delayed_ref handler finally. * So even we call qgroup_free_data(), it won't decrease reserved * space. * 2) Not written to disk * This means the reserved space should be freed here. However, * if a truncate invalidates the page (by clearing PageDirty) * and the page is accounted for while allocating extent * in btrfs_check_data_free_space() we let delayed_ref to * free the entire extent. */ if (PageDirty(page)) btrfs_qgroup_free_data(inode, NULL, page_start, PAGE_SIZE); if (!inode_evicting) { clear_extent_bit(tree, page_start, page_end, EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1, &cached_state); __btrfs_releasepage(page, GFP_NOFS); } ClearPageChecked(page); if (PagePrivate(page)) { ClearPagePrivate(page); set_page_private(page, 0); put_page(page); } } /* * btrfs_page_mkwrite() is not allowed to change the file size as it gets * called from a page fault handler when a page is first dirtied. Hence we must * be careful to check for EOF conditions here. We set the page up correctly * for a written page which means we get ENOSPC checking when writing into * holes and correct delalloc and unwritten extent mapping on filesystems that * support these features. * * We are not allowed to take the i_mutex here so we have to play games to * protect against truncate races as the page could now be beyond EOF. Because * truncate_setsize() writes the inode size before removing pages, once we have * the page lock we can determine safely if the page is beyond EOF. If it is not * beyond EOF, then the page is guaranteed safe against truncation until we * unlock the page. */ vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) { struct page *page = vmf->page; struct inode *inode = file_inode(vmf->vma->vm_file); struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; struct extent_changeset *data_reserved = NULL; char *kaddr; unsigned long zero_start; loff_t size; vm_fault_t ret; int ret2; int reserved = 0; u64 reserved_space; u64 page_start; u64 page_end; u64 end; reserved_space = PAGE_SIZE; sb_start_pagefault(inode->i_sb); page_start = page_offset(page); page_end = page_start + PAGE_SIZE - 1; end = page_end; /* * Reserving delalloc space after obtaining the page lock can lead to * deadlock. For example, if a dirty page is locked by this function * and the call to btrfs_delalloc_reserve_space() ends up triggering * dirty page write out, then the btrfs_writepage() function could * end up waiting indefinitely to get a lock on the page currently * being processed by btrfs_page_mkwrite() function. */ ret2 = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start, reserved_space); if (!ret2) { ret2 = file_update_time(vmf->vma->vm_file); reserved = 1; } if (ret2) { ret = vmf_error(ret2); if (reserved) goto out; goto out_noreserve; } ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */ again: lock_page(page); size = i_size_read(inode); if ((page->mapping != inode->i_mapping) || (page_start >= size)) { /* page got truncated out from underneath us */ goto out_unlock; } wait_on_page_writeback(page); lock_extent_bits(io_tree, page_start, page_end, &cached_state); set_page_extent_mapped(page); /* * we can't set the delalloc bits if there are pending ordered * extents. Drop our locks and wait for them to finish */ ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start, PAGE_SIZE); if (ordered) { unlock_extent_cached(io_tree, page_start, page_end, &cached_state); unlock_page(page); btrfs_start_ordered_extent(inode, ordered, 1); btrfs_put_ordered_extent(ordered); goto again; } if (page->index == ((size - 1) >> PAGE_SHIFT)) { reserved_space = round_up(size - page_start, fs_info->sectorsize); if (reserved_space < PAGE_SIZE) { end = page_start + reserved_space - 1; btrfs_delalloc_release_space(inode, data_reserved, page_start, PAGE_SIZE - reserved_space, true); } } /* * page_mkwrite gets called when the page is firstly dirtied after it's * faulted in, but write(2) could also dirty a page and set delalloc * bits, thus in this case for space account reason, we still need to * clear any delalloc bits within this page range since we have to * reserve data&meta space before lock_page() (see above comments). */ clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, end, EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, &cached_state); ret2 = btrfs_set_extent_delalloc(inode, page_start, end, 0, &cached_state, 0); if (ret2) { unlock_extent_cached(io_tree, page_start, page_end, &cached_state); ret = VM_FAULT_SIGBUS; goto out_unlock; } ret2 = 0; /* page is wholly or partially inside EOF */ if (page_start + PAGE_SIZE > size) zero_start = offset_in_page(size); else zero_start = PAGE_SIZE; if (zero_start != PAGE_SIZE) { kaddr = kmap(page); memset(kaddr + zero_start, 0, PAGE_SIZE - zero_start); flush_dcache_page(page); kunmap(page); } ClearPageChecked(page); set_page_dirty(page); SetPageUptodate(page); BTRFS_I(inode)->last_trans = fs_info->generation; BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid; BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit; unlock_extent_cached(io_tree, page_start, page_end, &cached_state); if (!ret2) { btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, true); sb_end_pagefault(inode->i_sb); extent_changeset_free(data_reserved); return VM_FAULT_LOCKED; } out_unlock: unlock_page(page); out: btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, (ret != 0)); btrfs_delalloc_release_space(inode, data_reserved, page_start, reserved_space, (ret != 0)); out_noreserve: sb_end_pagefault(inode->i_sb); extent_changeset_free(data_reserved); return ret; } static int btrfs_truncate(struct inode *inode, bool skip_writeback) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_block_rsv *rsv; int ret; struct btrfs_trans_handle *trans; u64 mask = fs_info->sectorsize - 1; u64 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1); if (!skip_writeback) { ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1); if (ret) return ret; } /* * Yes ladies and gentlemen, this is indeed ugly. We have a couple of * things going on here: * * 1) We need to reserve space to update our inode. * * 2) We need to have something to cache all the space that is going to * be free'd up by the truncate operation, but also have some slack * space reserved in case it uses space during the truncate (thank you * very much snapshotting). * * And we need these to be separate. The fact is we can use a lot of * space doing the truncate, and we have no earthly idea how much space * we will use, so we need the truncate reservation to be separate so it * doesn't end up using space reserved for updating the inode. We also * need to be able to stop the transaction and start a new one, which * means we need to be able to update the inode several times, and we * have no idea of knowing how many times that will be, so we can't just * reserve 1 item for the entirety of the operation, so that has to be * done separately as well. * * So that leaves us with * * 1) rsv - for the truncate reservation, which we will steal from the * transaction reservation. * 2) fs_info->trans_block_rsv - this will have 1 items worth left for * updating the inode. */ rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP); if (!rsv) return -ENOMEM; rsv->size = min_size; rsv->failfast = 1; /* * 1 for the truncate slack space * 1 for updating the inode. */ trans = btrfs_start_transaction(root, 2); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } /* Migrate the slack space for the truncate to our reserve */ ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv, min_size, false); BUG_ON(ret); /* * So if we truncate and then write and fsync we normally would just * write the extents that changed, which is a problem if we need to * first truncate that entire inode. So set this flag so we write out * all of the extents in the inode to the sync log so we're completely * safe. */ set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); trans->block_rsv = rsv; while (1) { ret = btrfs_truncate_inode_items(trans, root, inode, inode->i_size, BTRFS_EXTENT_DATA_KEY); trans->block_rsv = &fs_info->trans_block_rsv; if (ret != -ENOSPC && ret != -EAGAIN) break; ret = btrfs_update_inode(trans, root, inode); if (ret) break; btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); trans = btrfs_start_transaction(root, 2); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; break; } btrfs_block_rsv_release(fs_info, rsv, -1); ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv, min_size, false); BUG_ON(ret); /* shouldn't happen */ trans->block_rsv = rsv; } /* * We can't call btrfs_truncate_block inside a trans handle as we could * deadlock with freeze, if we got NEED_TRUNCATE_BLOCK then we know * we've truncated everything except the last little bit, and can do * btrfs_truncate_block and then update the disk_i_size. */ if (ret == NEED_TRUNCATE_BLOCK) { btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); ret = btrfs_truncate_block(inode, inode->i_size, 0, 0); if (ret) goto out; trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } btrfs_ordered_update_i_size(inode, inode->i_size, NULL); } if (trans) { int ret2; trans->block_rsv = &fs_info->trans_block_rsv; ret2 = btrfs_update_inode(trans, root, inode); if (ret2 && !ret) ret = ret2; ret2 = btrfs_end_transaction(trans); if (ret2 && !ret) ret = ret2; btrfs_btree_balance_dirty(fs_info); } out: btrfs_free_block_rsv(fs_info, rsv); return ret; } /* * create a new subvolume directory/inode (helper for the ioctl). */ int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, struct btrfs_root *new_root, struct btrfs_root *parent_root, u64 new_dirid) { struct inode *inode; int err; u64 index = 0; inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid, new_dirid, S_IFDIR | (~current_umask() & S_IRWXUGO), &index); if (IS_ERR(inode)) return PTR_ERR(inode); inode->i_op = &btrfs_dir_inode_operations; inode->i_fop = &btrfs_dir_file_operations; set_nlink(inode, 1); btrfs_i_size_write(BTRFS_I(inode), 0); unlock_new_inode(inode); err = btrfs_subvol_inherit_props(trans, new_root, parent_root); if (err) btrfs_err(new_root->fs_info, "error inheriting subvolume %llu properties: %d", new_root->root_key.objectid, err); err = btrfs_update_inode(trans, new_root, inode); iput(inode); return err; } struct inode *btrfs_alloc_inode(struct super_block *sb) { struct btrfs_fs_info *fs_info = btrfs_sb(sb); struct btrfs_inode *ei; struct inode *inode; ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_KERNEL); if (!ei) return NULL; ei->root = NULL; ei->generation = 0; ei->last_trans = 0; ei->last_sub_trans = 0; ei->logged_trans = 0; ei->delalloc_bytes = 0; ei->new_delalloc_bytes = 0; ei->defrag_bytes = 0; ei->disk_i_size = 0; ei->flags = 0; ei->csum_bytes = 0; ei->index_cnt = (u64)-1; ei->dir_index = 0; ei->last_unlink_trans = 0; ei->last_link_trans = 0; ei->last_log_commit = 0; spin_lock_init(&ei->lock); ei->outstanding_extents = 0; if (sb->s_magic != BTRFS_TEST_MAGIC) btrfs_init_metadata_block_rsv(fs_info, &ei->block_rsv, BTRFS_BLOCK_RSV_DELALLOC); ei->runtime_flags = 0; ei->prop_compress = BTRFS_COMPRESS_NONE; ei->defrag_compress = BTRFS_COMPRESS_NONE; ei->delayed_node = NULL; ei->i_otime.tv_sec = 0; ei->i_otime.tv_nsec = 0; inode = &ei->vfs_inode; extent_map_tree_init(&ei->extent_tree); extent_io_tree_init(&ei->io_tree, inode); extent_io_tree_init(&ei->io_failure_tree, inode); ei->io_tree.track_uptodate = 1; ei->io_failure_tree.track_uptodate = 1; atomic_set(&ei->sync_writers, 0); mutex_init(&ei->log_mutex); mutex_init(&ei->delalloc_mutex); btrfs_ordered_inode_tree_init(&ei->ordered_tree); INIT_LIST_HEAD(&ei->delalloc_inodes); INIT_LIST_HEAD(&ei->delayed_iput); RB_CLEAR_NODE(&ei->rb_node); init_rwsem(&ei->dio_sem); return inode; } #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS void btrfs_test_destroy_inode(struct inode *inode) { btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0); kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); } #endif static void btrfs_i_callback(struct rcu_head *head) { struct inode *inode = container_of(head, struct inode, i_rcu); kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); } void btrfs_destroy_inode(struct inode *inode) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_ordered_extent *ordered; struct btrfs_root *root = BTRFS_I(inode)->root; WARN_ON(!hlist_empty(&inode->i_dentry)); WARN_ON(inode->i_data.nrpages); WARN_ON(BTRFS_I(inode)->block_rsv.reserved); WARN_ON(BTRFS_I(inode)->block_rsv.size); WARN_ON(BTRFS_I(inode)->outstanding_extents); WARN_ON(BTRFS_I(inode)->delalloc_bytes); WARN_ON(BTRFS_I(inode)->new_delalloc_bytes); WARN_ON(BTRFS_I(inode)->csum_bytes); WARN_ON(BTRFS_I(inode)->defrag_bytes); /* * This can happen where we create an inode, but somebody else also * created the same inode and we need to destroy the one we already * created. */ if (!root) goto free; while (1) { ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1); if (!ordered) break; else { btrfs_err(fs_info, "found ordered extent %llu %llu on inode cleanup", ordered->file_offset, ordered->len); btrfs_remove_ordered_extent(inode, ordered); btrfs_put_ordered_extent(ordered); btrfs_put_ordered_extent(ordered); } } btrfs_qgroup_check_reserved_leak(inode); inode_tree_del(inode); btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0); free: call_rcu(&inode->i_rcu, btrfs_i_callback); } int btrfs_drop_inode(struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; if (root == NULL) return 1; /* the snap/subvol tree is on deleting */ if (btrfs_root_refs(&root->root_item) == 0) return 1; else return generic_drop_inode(inode); } static void init_once(void *foo) { struct btrfs_inode *ei = (struct btrfs_inode *) foo; inode_init_once(&ei->vfs_inode); } void __cold btrfs_destroy_cachep(void) { /* * Make sure all delayed rcu free inodes are flushed before we * destroy cache. */ rcu_barrier(); kmem_cache_destroy(btrfs_inode_cachep); kmem_cache_destroy(btrfs_trans_handle_cachep); kmem_cache_destroy(btrfs_path_cachep); kmem_cache_destroy(btrfs_free_space_cachep); } int __init btrfs_init_cachep(void) { btrfs_inode_cachep = kmem_cache_create("btrfs_inode", sizeof(struct btrfs_inode), 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT, init_once); if (!btrfs_inode_cachep) goto fail; btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle", sizeof(struct btrfs_trans_handle), 0, SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL); if (!btrfs_trans_handle_cachep) goto fail; btrfs_path_cachep = kmem_cache_create("btrfs_path", sizeof(struct btrfs_path), 0, SLAB_MEM_SPREAD, NULL); if (!btrfs_path_cachep) goto fail; btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space", sizeof(struct btrfs_free_space), 0, SLAB_MEM_SPREAD, NULL); if (!btrfs_free_space_cachep) goto fail; return 0; fail: btrfs_destroy_cachep(); return -ENOMEM; } static int btrfs_getattr(const struct path *path, struct kstat *stat, u32 request_mask, unsigned int flags) { u64 delalloc_bytes; struct inode *inode = d_inode(path->dentry); u32 blocksize = inode->i_sb->s_blocksize; u32 bi_flags = BTRFS_I(inode)->flags; stat->result_mask |= STATX_BTIME; stat->btime.tv_sec = BTRFS_I(inode)->i_otime.tv_sec; stat->btime.tv_nsec = BTRFS_I(inode)->i_otime.tv_nsec; if (bi_flags & BTRFS_INODE_APPEND) stat->attributes |= STATX_ATTR_APPEND; if (bi_flags & BTRFS_INODE_COMPRESS) stat->attributes |= STATX_ATTR_COMPRESSED; if (bi_flags & BTRFS_INODE_IMMUTABLE) stat->attributes |= STATX_ATTR_IMMUTABLE; if (bi_flags & BTRFS_INODE_NODUMP) stat->attributes |= STATX_ATTR_NODUMP; stat->attributes_mask |= (STATX_ATTR_APPEND | STATX_ATTR_COMPRESSED | STATX_ATTR_IMMUTABLE | STATX_ATTR_NODUMP); generic_fillattr(inode, stat); stat->dev = BTRFS_I(inode)->root->anon_dev; spin_lock(&BTRFS_I(inode)->lock); delalloc_bytes = BTRFS_I(inode)->new_delalloc_bytes; spin_unlock(&BTRFS_I(inode)->lock); stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) + ALIGN(delalloc_bytes, blocksize)) >> 9; return 0; } static int btrfs_rename_exchange(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) { struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(old_dir)->root; struct btrfs_root *dest = BTRFS_I(new_dir)->root; struct inode *new_inode = new_dentry->d_inode; struct inode *old_inode = old_dentry->d_inode; struct timespec64 ctime = current_time(old_inode); struct dentry *parent; u64 old_ino = btrfs_ino(BTRFS_I(old_inode)); u64 new_ino = btrfs_ino(BTRFS_I(new_inode)); u64 old_idx = 0; u64 new_idx = 0; u64 root_objectid; int ret; bool root_log_pinned = false; bool dest_log_pinned = false; struct btrfs_log_ctx ctx_root; struct btrfs_log_ctx ctx_dest; bool sync_log_root = false; bool sync_log_dest = false; bool commit_transaction = false; /* we only allow rename subvolume link between subvolumes */ if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) return -EXDEV; btrfs_init_log_ctx(&ctx_root, old_inode); btrfs_init_log_ctx(&ctx_dest, new_inode); /* close the race window with snapshot create/destroy ioctl */ if (old_ino == BTRFS_FIRST_FREE_OBJECTID) down_read(&fs_info->subvol_sem); if (new_ino == BTRFS_FIRST_FREE_OBJECTID) down_read(&fs_info->subvol_sem); /* * We want to reserve the absolute worst case amount of items. So if * both inodes are subvols and we need to unlink them then that would * require 4 item modifications, but if they are both normal inodes it * would require 5 item modifications, so we'll assume their normal * inodes. So 5 * 2 is 10, plus 2 for the new links, so 12 total items * should cover the worst case number of items we'll modify. */ trans = btrfs_start_transaction(root, 12); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_notrans; } /* * We need to find a free sequence number both in the source and * in the destination directory for the exchange. */ ret = btrfs_set_inode_index(BTRFS_I(new_dir), &old_idx); if (ret) goto out_fail; ret = btrfs_set_inode_index(BTRFS_I(old_dir), &new_idx); if (ret) goto out_fail; BTRFS_I(old_inode)->dir_index = 0ULL; BTRFS_I(new_inode)->dir_index = 0ULL; /* Reference for the source. */ if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { /* force full log commit if subvolume involved. */ btrfs_set_log_full_commit(fs_info, trans); } else { btrfs_pin_log_trans(root); root_log_pinned = true; ret = btrfs_insert_inode_ref(trans, dest, new_dentry->d_name.name, new_dentry->d_name.len, old_ino, btrfs_ino(BTRFS_I(new_dir)), old_idx); if (ret) goto out_fail; } /* And now for the dest. */ if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { /* force full log commit if subvolume involved. */ btrfs_set_log_full_commit(fs_info, trans); } else { btrfs_pin_log_trans(dest); dest_log_pinned = true; ret = btrfs_insert_inode_ref(trans, root, old_dentry->d_name.name, old_dentry->d_name.len, new_ino, btrfs_ino(BTRFS_I(old_dir)), new_idx); if (ret) goto out_fail; } /* Update inode version and ctime/mtime. */ inode_inc_iversion(old_dir); inode_inc_iversion(new_dir); inode_inc_iversion(old_inode); inode_inc_iversion(new_inode); old_dir->i_ctime = old_dir->i_mtime = ctime; new_dir->i_ctime = new_dir->i_mtime = ctime; old_inode->i_ctime = ctime; new_inode->i_ctime = ctime; if (old_dentry->d_parent != new_dentry->d_parent) { btrfs_record_unlink_dir(trans, BTRFS_I(old_dir), BTRFS_I(old_inode), 1); btrfs_record_unlink_dir(trans, BTRFS_I(new_dir), BTRFS_I(new_inode), 1); } /* src is a subvolume */ if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; ret = btrfs_unlink_subvol(trans, old_dir, root_objectid, old_dentry->d_name.name, old_dentry->d_name.len); } else { /* src is an inode */ ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir), BTRFS_I(old_dentry->d_inode), old_dentry->d_name.name, old_dentry->d_name.len); if (!ret) ret = btrfs_update_inode(trans, root, old_inode); } if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } /* dest is a subvolume */ if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { root_objectid = BTRFS_I(new_inode)->root->root_key.objectid; ret = btrfs_unlink_subvol(trans, new_dir, root_objectid, new_dentry->d_name.name, new_dentry->d_name.len); } else { /* dest is an inode */ ret = __btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir), BTRFS_I(new_dentry->d_inode), new_dentry->d_name.name, new_dentry->d_name.len); if (!ret) ret = btrfs_update_inode(trans, dest, new_inode); } if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), new_dentry->d_name.name, new_dentry->d_name.len, 0, old_idx); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } ret = btrfs_add_link(trans, BTRFS_I(old_dir), BTRFS_I(new_inode), old_dentry->d_name.name, old_dentry->d_name.len, 0, new_idx); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } if (old_inode->i_nlink == 1) BTRFS_I(old_inode)->dir_index = old_idx; if (new_inode->i_nlink == 1) BTRFS_I(new_inode)->dir_index = new_idx; if (root_log_pinned) { parent = new_dentry->d_parent; ret = btrfs_log_new_name(trans, BTRFS_I(old_inode), BTRFS_I(old_dir), parent, false, &ctx_root); if (ret == BTRFS_NEED_LOG_SYNC) sync_log_root = true; else if (ret == BTRFS_NEED_TRANS_COMMIT) commit_transaction = true; ret = 0; btrfs_end_log_trans(root); root_log_pinned = false; } if (dest_log_pinned) { if (!commit_transaction) { parent = old_dentry->d_parent; ret = btrfs_log_new_name(trans, BTRFS_I(new_inode), BTRFS_I(new_dir), parent, false, &ctx_dest); if (ret == BTRFS_NEED_LOG_SYNC) sync_log_dest = true; else if (ret == BTRFS_NEED_TRANS_COMMIT) commit_transaction = true; ret = 0; } btrfs_end_log_trans(dest); dest_log_pinned = false; } out_fail: /* * If we have pinned a log and an error happened, we unpin tasks * trying to sync the log and force them to fallback to a transaction * commit if the log currently contains any of the inodes involved in * this rename operation (to ensure we do not persist a log with an * inconsistent state for any of these inodes or leading to any * inconsistencies when replayed). If the transaction was aborted, the * abortion reason is propagated to userspace when attempting to commit * the transaction. If the log does not contain any of these inodes, we * allow the tasks to sync it. */ if (ret && (root_log_pinned || dest_log_pinned)) { if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) || btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) || btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) || (new_inode && btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation))) btrfs_set_log_full_commit(fs_info, trans); if (root_log_pinned) { btrfs_end_log_trans(root); root_log_pinned = false; } if (dest_log_pinned) { btrfs_end_log_trans(dest); dest_log_pinned = false; } } if (!ret && sync_log_root && !commit_transaction) { ret = btrfs_sync_log(trans, BTRFS_I(old_inode)->root, &ctx_root); if (ret) commit_transaction = true; } if (!ret && sync_log_dest && !commit_transaction) { ret = btrfs_sync_log(trans, BTRFS_I(new_inode)->root, &ctx_dest); if (ret) commit_transaction = true; } if (commit_transaction) { ret = btrfs_commit_transaction(trans); } else { int ret2; ret2 = btrfs_end_transaction(trans); ret = ret ? ret : ret2; } out_notrans: if (new_ino == BTRFS_FIRST_FREE_OBJECTID) up_read(&fs_info->subvol_sem); if (old_ino == BTRFS_FIRST_FREE_OBJECTID) up_read(&fs_info->subvol_sem); return ret; } static int btrfs_whiteout_for_rename(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *dir, struct dentry *dentry) { int ret; struct inode *inode; u64 objectid; u64 index; ret = btrfs_find_free_ino(root, &objectid); if (ret) return ret; inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, S_IFCHR | WHITEOUT_MODE, &index); if (IS_ERR(inode)) { ret = PTR_ERR(inode); return ret; } inode->i_op = &btrfs_special_inode_operations; init_special_inode(inode, inode->i_mode, WHITEOUT_DEV); ret = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); if (ret) goto out; ret = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 0, index); if (ret) goto out; ret = btrfs_update_inode(trans, root, inode); out: unlock_new_inode(inode); if (ret) inode_dec_link_count(inode); iput(inode); return ret; } static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags) { struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb); struct btrfs_trans_handle *trans; unsigned int trans_num_items; struct btrfs_root *root = BTRFS_I(old_dir)->root; struct btrfs_root *dest = BTRFS_I(new_dir)->root; struct inode *new_inode = d_inode(new_dentry); struct inode *old_inode = d_inode(old_dentry); u64 index = 0; u64 root_objectid; int ret; u64 old_ino = btrfs_ino(BTRFS_I(old_inode)); bool log_pinned = false; struct btrfs_log_ctx ctx; bool sync_log = false; bool commit_transaction = false; if (btrfs_ino(BTRFS_I(new_dir)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) return -EPERM; /* we only allow rename subvolume link between subvolumes */ if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) return -EXDEV; if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID || (new_inode && btrfs_ino(BTRFS_I(new_inode)) == BTRFS_FIRST_FREE_OBJECTID)) return -ENOTEMPTY; if (S_ISDIR(old_inode->i_mode) && new_inode && new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) return -ENOTEMPTY; /* check for collisions, even if the name isn't there */ ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino, new_dentry->d_name.name, new_dentry->d_name.len); if (ret) { if (ret == -EEXIST) { /* we shouldn't get * eexist without a new_inode */ if (WARN_ON(!new_inode)) { return ret; } } else { /* maybe -EOVERFLOW */ return ret; } } ret = 0; /* * we're using rename to replace one file with another. Start IO on it * now so we don't add too much work to the end of the transaction */ if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size) filemap_flush(old_inode->i_mapping); /* close the racy window with snapshot create/destroy ioctl */ if (old_ino == BTRFS_FIRST_FREE_OBJECTID) down_read(&fs_info->subvol_sem); /* * We want to reserve the absolute worst case amount of items. So if * both inodes are subvols and we need to unlink them then that would * require 4 item modifications, but if they are both normal inodes it * would require 5 item modifications, so we'll assume they are normal * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items * should cover the worst case number of items we'll modify. * If our rename has the whiteout flag, we need more 5 units for the * new inode (1 inode item, 1 inode ref, 2 dir items and 1 xattr item * when selinux is enabled). */ trans_num_items = 11; if (flags & RENAME_WHITEOUT) trans_num_items += 5; trans = btrfs_start_transaction(root, trans_num_items); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_notrans; } if (dest != root) btrfs_record_root_in_trans(trans, dest); ret = btrfs_set_inode_index(BTRFS_I(new_dir), &index); if (ret) goto out_fail; BTRFS_I(old_inode)->dir_index = 0ULL; if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { /* force full log commit if subvolume involved. */ btrfs_set_log_full_commit(fs_info, trans); } else { btrfs_pin_log_trans(root); log_pinned = true; ret = btrfs_insert_inode_ref(trans, dest, new_dentry->d_name.name, new_dentry->d_name.len, old_ino, btrfs_ino(BTRFS_I(new_dir)), index); if (ret) goto out_fail; } inode_inc_iversion(old_dir); inode_inc_iversion(new_dir); inode_inc_iversion(old_inode); old_dir->i_ctime = old_dir->i_mtime = new_dir->i_ctime = new_dir->i_mtime = old_inode->i_ctime = current_time(old_dir); if (old_dentry->d_parent != new_dentry->d_parent) btrfs_record_unlink_dir(trans, BTRFS_I(old_dir), BTRFS_I(old_inode), 1); if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; ret = btrfs_unlink_subvol(trans, old_dir, root_objectid, old_dentry->d_name.name, old_dentry->d_name.len); } else { ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir), BTRFS_I(d_inode(old_dentry)), old_dentry->d_name.name, old_dentry->d_name.len); if (!ret) ret = btrfs_update_inode(trans, root, old_inode); } if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } if (new_inode) { inode_inc_iversion(new_inode); new_inode->i_ctime = current_time(new_inode); if (unlikely(btrfs_ino(BTRFS_I(new_inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { root_objectid = BTRFS_I(new_inode)->location.objectid; ret = btrfs_unlink_subvol(trans, new_dir, root_objectid, new_dentry->d_name.name, new_dentry->d_name.len); BUG_ON(new_inode->i_nlink == 0); } else { ret = btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir), BTRFS_I(d_inode(new_dentry)), new_dentry->d_name.name, new_dentry->d_name.len); } if (!ret && new_inode->i_nlink == 0) ret = btrfs_orphan_add(trans, BTRFS_I(d_inode(new_dentry))); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } } ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), new_dentry->d_name.name, new_dentry->d_name.len, 0, index); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } if (old_inode->i_nlink == 1) BTRFS_I(old_inode)->dir_index = index; if (log_pinned) { struct dentry *parent = new_dentry->d_parent; btrfs_init_log_ctx(&ctx, old_inode); ret = btrfs_log_new_name(trans, BTRFS_I(old_inode), BTRFS_I(old_dir), parent, false, &ctx); if (ret == BTRFS_NEED_LOG_SYNC) sync_log = true; else if (ret == BTRFS_NEED_TRANS_COMMIT) commit_transaction = true; ret = 0; btrfs_end_log_trans(root); log_pinned = false; } if (flags & RENAME_WHITEOUT) { ret = btrfs_whiteout_for_rename(trans, root, old_dir, old_dentry); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } } out_fail: /* * If we have pinned the log and an error happened, we unpin tasks * trying to sync the log and force them to fallback to a transaction * commit if the log currently contains any of the inodes involved in * this rename operation (to ensure we do not persist a log with an * inconsistent state for any of these inodes or leading to any * inconsistencies when replayed). If the transaction was aborted, the * abortion reason is propagated to userspace when attempting to commit * the transaction. If the log does not contain any of these inodes, we * allow the tasks to sync it. */ if (ret && log_pinned) { if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) || btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) || btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) || (new_inode && btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation))) btrfs_set_log_full_commit(fs_info, trans); btrfs_end_log_trans(root); log_pinned = false; } if (!ret && sync_log) { ret = btrfs_sync_log(trans, BTRFS_I(old_inode)->root, &ctx); if (ret) commit_transaction = true; } if (commit_transaction) { ret = btrfs_commit_transaction(trans); } else { int ret2; ret2 = btrfs_end_transaction(trans); ret = ret ? ret : ret2; } out_notrans: if (old_ino == BTRFS_FIRST_FREE_OBJECTID) up_read(&fs_info->subvol_sem); return ret; } static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags) { if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) return -EINVAL; if (flags & RENAME_EXCHANGE) return btrfs_rename_exchange(old_dir, old_dentry, new_dir, new_dentry); return btrfs_rename(old_dir, old_dentry, new_dir, new_dentry, flags); } struct btrfs_delalloc_work { struct inode *inode; struct completion completion; struct list_head list; struct btrfs_work work; }; static void btrfs_run_delalloc_work(struct btrfs_work *work) { struct btrfs_delalloc_work *delalloc_work; struct inode *inode; delalloc_work = container_of(work, struct btrfs_delalloc_work, work); inode = delalloc_work->inode; filemap_flush(inode->i_mapping); if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &BTRFS_I(inode)->runtime_flags)) filemap_flush(inode->i_mapping); iput(inode); complete(&delalloc_work->completion); } static struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode) { struct btrfs_delalloc_work *work; work = kmalloc(sizeof(*work), GFP_NOFS); if (!work) return NULL; init_completion(&work->completion); INIT_LIST_HEAD(&work->list); work->inode = inode; WARN_ON_ONCE(!inode); btrfs_init_work(&work->work, btrfs_flush_delalloc_helper, btrfs_run_delalloc_work, NULL, NULL); return work; } /* * some fairly slow code that needs optimization. This walks the list * of all the inodes with pending delalloc and forces them to disk. */ static int start_delalloc_inodes(struct btrfs_root *root, int nr, bool snapshot) { struct btrfs_inode *binode; struct inode *inode; struct btrfs_delalloc_work *work, *next; struct list_head works; struct list_head splice; int ret = 0; INIT_LIST_HEAD(&works); INIT_LIST_HEAD(&splice); mutex_lock(&root->delalloc_mutex); spin_lock(&root->delalloc_lock); list_splice_init(&root->delalloc_inodes, &splice); while (!list_empty(&splice)) { binode = list_entry(splice.next, struct btrfs_inode, delalloc_inodes); list_move_tail(&binode->delalloc_inodes, &root->delalloc_inodes); inode = igrab(&binode->vfs_inode); if (!inode) { cond_resched_lock(&root->delalloc_lock); continue; } spin_unlock(&root->delalloc_lock); if (snapshot) set_bit(BTRFS_INODE_SNAPSHOT_FLUSH, &binode->runtime_flags); work = btrfs_alloc_delalloc_work(inode); if (!work) { iput(inode); ret = -ENOMEM; goto out; } list_add_tail(&work->list, &works); btrfs_queue_work(root->fs_info->flush_workers, &work->work); ret++; if (nr != -1 && ret >= nr) goto out; cond_resched(); spin_lock(&root->delalloc_lock); } spin_unlock(&root->delalloc_lock); out: list_for_each_entry_safe(work, next, &works, list) { list_del_init(&work->list); wait_for_completion(&work->completion); kfree(work); } if (!list_empty(&splice)) { spin_lock(&root->delalloc_lock); list_splice_tail(&splice, &root->delalloc_inodes); spin_unlock(&root->delalloc_lock); } mutex_unlock(&root->delalloc_mutex); return ret; } int btrfs_start_delalloc_snapshot(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; int ret; if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) return -EROFS; ret = start_delalloc_inodes(root, -1, true); if (ret > 0) ret = 0; return ret; } int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int nr) { struct btrfs_root *root; struct list_head splice; int ret; if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) return -EROFS; INIT_LIST_HEAD(&splice); mutex_lock(&fs_info->delalloc_root_mutex); spin_lock(&fs_info->delalloc_root_lock); list_splice_init(&fs_info->delalloc_roots, &splice); while (!list_empty(&splice) && nr) { root = list_first_entry(&splice, struct btrfs_root, delalloc_root); root = btrfs_grab_fs_root(root); BUG_ON(!root); list_move_tail(&root->delalloc_root, &fs_info->delalloc_roots); spin_unlock(&fs_info->delalloc_root_lock); ret = start_delalloc_inodes(root, nr, false); btrfs_put_fs_root(root); if (ret < 0) goto out; if (nr != -1) { nr -= ret; WARN_ON(nr < 0); } spin_lock(&fs_info->delalloc_root_lock); } spin_unlock(&fs_info->delalloc_root_lock); ret = 0; out: if (!list_empty(&splice)) { spin_lock(&fs_info->delalloc_root_lock); list_splice_tail(&splice, &fs_info->delalloc_roots); spin_unlock(&fs_info->delalloc_root_lock); } mutex_unlock(&fs_info->delalloc_root_mutex); return ret; } static int btrfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) { struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_path *path; struct btrfs_key key; struct inode *inode = NULL; int err; u64 objectid; u64 index = 0; int name_len; int datasize; unsigned long ptr; struct btrfs_file_extent_item *ei; struct extent_buffer *leaf; name_len = strlen(symname); if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info)) return -ENAMETOOLONG; /* * 2 items for inode item and ref * 2 items for dir items * 1 item for updating parent inode item * 1 item for the inline extent item * 1 item for xattr if selinux is on */ trans = btrfs_start_transaction(root, 7); if (IS_ERR(trans)) return PTR_ERR(trans); err = btrfs_find_free_ino(root, &objectid); if (err) goto out_unlock; inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, S_IFLNK|S_IRWXUGO, &index); if (IS_ERR(inode)) { err = PTR_ERR(inode); inode = NULL; goto out_unlock; } /* * If the active LSM wants to access the inode during * d_instantiate it needs these. Smack checks to see * if the filesystem supports xattrs by looking at the * ops vector. */ inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; inode->i_mapping->a_ops = &btrfs_aops; BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); if (err) goto out_unlock; path = btrfs_alloc_path(); if (!path) { err = -ENOMEM; goto out_unlock; } key.objectid = btrfs_ino(BTRFS_I(inode)); key.offset = 0; key.type = BTRFS_EXTENT_DATA_KEY; datasize = btrfs_file_extent_calc_inline_size(name_len); err = btrfs_insert_empty_item(trans, root, path, &key, datasize); if (err) { btrfs_free_path(path); goto out_unlock; } leaf = path->nodes[0]; ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, ei, trans->transid); btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); btrfs_set_file_extent_encryption(leaf, ei, 0); btrfs_set_file_extent_compression(leaf, ei, 0); btrfs_set_file_extent_other_encoding(leaf, ei, 0); btrfs_set_file_extent_ram_bytes(leaf, ei, name_len); ptr = btrfs_file_extent_inline_start(ei); write_extent_buffer(leaf, symname, ptr, name_len); btrfs_mark_buffer_dirty(leaf); btrfs_free_path(path); inode->i_op = &btrfs_symlink_inode_operations; inode_nohighmem(inode); inode->i_mapping->a_ops = &btrfs_aops; inode_set_bytes(inode, name_len); btrfs_i_size_write(BTRFS_I(inode), name_len); err = btrfs_update_inode(trans, root, inode); /* * Last step, add directory indexes for our symlink inode. This is the * last step to avoid extra cleanup of these indexes if an error happens * elsewhere above. */ if (!err) err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 0, index); if (err) goto out_unlock; d_instantiate_new(dentry, inode); out_unlock: btrfs_end_transaction(trans); if (err && inode) { inode_dec_link_count(inode); discard_new_inode(inode); } btrfs_btree_balance_dirty(fs_info); return err; } static int __btrfs_prealloc_file_range(struct inode *inode, int mode, u64 start, u64 num_bytes, u64 min_size, loff_t actual_len, u64 *alloc_hint, struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; struct extent_map *em; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_key ins; u64 cur_offset = start; u64 i_size; u64 cur_bytes; u64 last_alloc = (u64)-1; int ret = 0; bool own_trans = true; u64 end = start + num_bytes - 1; if (trans) own_trans = false; while (num_bytes > 0) { if (own_trans) { trans = btrfs_start_transaction(root, 3); if (IS_ERR(trans)) { ret = PTR_ERR(trans); break; } } cur_bytes = min_t(u64, num_bytes, SZ_256M); cur_bytes = max(cur_bytes, min_size); /* * If we are severely fragmented we could end up with really * small allocations, so if the allocator is returning small * chunks lets make its job easier by only searching for those * sized chunks. */ cur_bytes = min(cur_bytes, last_alloc); ret = btrfs_reserve_extent(root, cur_bytes, cur_bytes, min_size, 0, *alloc_hint, &ins, 1, 0); if (ret) { if (own_trans) btrfs_end_transaction(trans); break; } btrfs_dec_block_group_reservations(fs_info, ins.objectid); last_alloc = ins.offset; ret = insert_reserved_file_extent(trans, inode, cur_offset, ins.objectid, ins.offset, ins.offset, ins.offset, 0, 0, 0, BTRFS_FILE_EXTENT_PREALLOC); if (ret) { btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0); btrfs_abort_transaction(trans, ret); if (own_trans) btrfs_end_transaction(trans); break; } btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, cur_offset + ins.offset -1, 0); em = alloc_extent_map(); if (!em) { set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); goto next; } em->start = cur_offset; em->orig_start = cur_offset; em->len = ins.offset; em->block_start = ins.objectid; em->block_len = ins.offset; em->orig_block_len = ins.offset; em->ram_bytes = ins.offset; em->bdev = fs_info->fs_devices->latest_bdev; set_bit(EXTENT_FLAG_PREALLOC, &em->flags); em->generation = trans->transid; while (1) { write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em, 1); write_unlock(&em_tree->lock); if (ret != -EEXIST) break; btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, cur_offset + ins.offset - 1, 0); } free_extent_map(em); next: num_bytes -= ins.offset; cur_offset += ins.offset; *alloc_hint = ins.objectid + ins.offset; inode_inc_iversion(inode); inode->i_ctime = current_time(inode); BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC; if (!(mode & FALLOC_FL_KEEP_SIZE) && (actual_len > inode->i_size) && (cur_offset > inode->i_size)) { if (cur_offset > actual_len) i_size = actual_len; else i_size = cur_offset; i_size_write(inode, i_size); btrfs_ordered_update_i_size(inode, i_size, NULL); } ret = btrfs_update_inode(trans, root, inode); if (ret) { btrfs_abort_transaction(trans, ret); if (own_trans) btrfs_end_transaction(trans); break; } if (own_trans) btrfs_end_transaction(trans); } if (cur_offset < end) btrfs_free_reserved_data_space(inode, NULL, cur_offset, end - cur_offset + 1); return ret; } int btrfs_prealloc_file_range(struct inode *inode, int mode, u64 start, u64 num_bytes, u64 min_size, loff_t actual_len, u64 *alloc_hint) { return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, min_size, actual_len, alloc_hint, NULL); } int btrfs_prealloc_file_range_trans(struct inode *inode, struct btrfs_trans_handle *trans, int mode, u64 start, u64 num_bytes, u64 min_size, loff_t actual_len, u64 *alloc_hint) { return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, min_size, actual_len, alloc_hint, trans); } static int btrfs_set_page_dirty(struct page *page) { return __set_page_dirty_nobuffers(page); } static int btrfs_permission(struct inode *inode, int mask) { struct btrfs_root *root = BTRFS_I(inode)->root; umode_t mode = inode->i_mode; if (mask & MAY_WRITE && (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) { if (btrfs_root_readonly(root)) return -EROFS; if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) return -EACCES; } return generic_permission(inode, mask); } static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) { struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(dir)->root; struct inode *inode = NULL; u64 objectid; u64 index; int ret = 0; /* * 5 units required for adding orphan entry */ trans = btrfs_start_transaction(root, 5); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_find_free_ino(root, &objectid); if (ret) goto out; inode = btrfs_new_inode(trans, root, dir, NULL, 0, btrfs_ino(BTRFS_I(dir)), objectid, mode, &index); if (IS_ERR(inode)) { ret = PTR_ERR(inode); inode = NULL; goto out; } inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; inode->i_mapping->a_ops = &btrfs_aops; BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; ret = btrfs_init_inode_security(trans, inode, dir, NULL); if (ret) goto out; ret = btrfs_update_inode(trans, root, inode); if (ret) goto out; ret = btrfs_orphan_add(trans, BTRFS_I(inode)); if (ret) goto out; /* * We set number of links to 0 in btrfs_new_inode(), and here we set * it to 1 because d_tmpfile() will issue a warning if the count is 0, * through: * * d_tmpfile() -> inode_dec_link_count() -> drop_nlink() */ set_nlink(inode, 1); d_tmpfile(dentry, inode); unlock_new_inode(inode); mark_inode_dirty(inode); out: btrfs_end_transaction(trans); if (ret && inode) discard_new_inode(inode); btrfs_btree_balance_dirty(fs_info); return ret; } void btrfs_set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) { struct inode *inode = tree->private_data; unsigned long index = start >> PAGE_SHIFT; unsigned long end_index = end >> PAGE_SHIFT; struct page *page; while (index <= end_index) { page = find_get_page(inode->i_mapping, index); ASSERT(page); /* Pages should be in the extent_io_tree */ set_page_writeback(page); put_page(page); index++; } } #ifdef CONFIG_SWAP /* * Add an entry indicating a block group or device which is pinned by a * swapfile. Returns 0 on success, 1 if there is already an entry for it, or a * negative errno on failure. */ static int btrfs_add_swapfile_pin(struct inode *inode, void *ptr, bool is_block_group) { struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; struct btrfs_swapfile_pin *sp, *entry; struct rb_node **p; struct rb_node *parent = NULL; sp = kmalloc(sizeof(*sp), GFP_NOFS); if (!sp) return -ENOMEM; sp->ptr = ptr; sp->inode = inode; sp->is_block_group = is_block_group; spin_lock(&fs_info->swapfile_pins_lock); p = &fs_info->swapfile_pins.rb_node; while (*p) { parent = *p; entry = rb_entry(parent, struct btrfs_swapfile_pin, node); if (sp->ptr < entry->ptr || (sp->ptr == entry->ptr && sp->inode < entry->inode)) { p = &(*p)->rb_left; } else if (sp->ptr > entry->ptr || (sp->ptr == entry->ptr && sp->inode > entry->inode)) { p = &(*p)->rb_right; } else { spin_unlock(&fs_info->swapfile_pins_lock); kfree(sp); return 1; } } rb_link_node(&sp->node, parent, p); rb_insert_color(&sp->node, &fs_info->swapfile_pins); spin_unlock(&fs_info->swapfile_pins_lock); return 0; } /* Free all of the entries pinned by this swapfile. */ static void btrfs_free_swapfile_pins(struct inode *inode) { struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; struct btrfs_swapfile_pin *sp; struct rb_node *node, *next; spin_lock(&fs_info->swapfile_pins_lock); node = rb_first(&fs_info->swapfile_pins); while (node) { next = rb_next(node); sp = rb_entry(node, struct btrfs_swapfile_pin, node); if (sp->inode == inode) { rb_erase(&sp->node, &fs_info->swapfile_pins); if (sp->is_block_group) btrfs_put_block_group(sp->ptr); kfree(sp); } node = next; } spin_unlock(&fs_info->swapfile_pins_lock); } struct btrfs_swap_info { u64 start; u64 block_start; u64 block_len; u64 lowest_ppage; u64 highest_ppage; unsigned long nr_pages; int nr_extents; }; static int btrfs_add_swap_extent(struct swap_info_struct *sis, struct btrfs_swap_info *bsi) { unsigned long nr_pages; u64 first_ppage, first_ppage_reported, next_ppage; int ret; first_ppage = ALIGN(bsi->block_start, PAGE_SIZE) >> PAGE_SHIFT; next_ppage = ALIGN_DOWN(bsi->block_start + bsi->block_len, PAGE_SIZE) >> PAGE_SHIFT; if (first_ppage >= next_ppage) return 0; nr_pages = next_ppage - first_ppage; first_ppage_reported = first_ppage; if (bsi->start == 0) first_ppage_reported++; if (bsi->lowest_ppage > first_ppage_reported) bsi->lowest_ppage = first_ppage_reported; if (bsi->highest_ppage < (next_ppage - 1)) bsi->highest_ppage = next_ppage - 1; ret = add_swap_extent(sis, bsi->nr_pages, nr_pages, first_ppage); if (ret < 0) return ret; bsi->nr_extents += ret; bsi->nr_pages += nr_pages; return 0; } static void btrfs_swap_deactivate(struct file *file) { struct inode *inode = file_inode(file); btrfs_free_swapfile_pins(inode); atomic_dec(&BTRFS_I(inode)->root->nr_swapfiles); } static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file, sector_t *span) { struct inode *inode = file_inode(file); struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_state *cached_state = NULL; struct extent_map *em = NULL; struct btrfs_device *device = NULL; struct btrfs_swap_info bsi = { .lowest_ppage = (sector_t)-1ULL, }; int ret = 0; u64 isize; u64 start; /* * If the swap file was just created, make sure delalloc is done. If the * file changes again after this, the user is doing something stupid and * we don't really care. */ ret = btrfs_wait_ordered_range(inode, 0, (u64)-1); if (ret) return ret; /* * The inode is locked, so these flags won't change after we check them. */ if (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS) { btrfs_warn(fs_info, "swapfile must not be compressed"); return -EINVAL; } if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)) { btrfs_warn(fs_info, "swapfile must not be copy-on-write"); return -EINVAL; } if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { btrfs_warn(fs_info, "swapfile must not be checksummed"); return -EINVAL; } /* * Balance or device remove/replace/resize can move stuff around from * under us. The EXCL_OP flag makes sure they aren't running/won't run * concurrently while we are mapping the swap extents, and * fs_info->swapfile_pins prevents them from running while the swap file * is active and moving the extents. Note that this also prevents a * concurrent device add which isn't actually necessary, but it's not * really worth the trouble to allow it. */ if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { btrfs_warn(fs_info, "cannot activate swapfile while exclusive operation is running"); return -EBUSY; } /* * Snapshots can create extents which require COW even if NODATACOW is * set. We use this counter to prevent snapshots. We must increment it * before walking the extents because we don't want a concurrent * snapshot to run after we've already checked the extents. */ atomic_inc(&BTRFS_I(inode)->root->nr_swapfiles); isize = ALIGN_DOWN(inode->i_size, fs_info->sectorsize); lock_extent_bits(io_tree, 0, isize - 1, &cached_state); start = 0; while (start < isize) { u64 logical_block_start, physical_block_start; struct btrfs_block_group_cache *bg; u64 len = isize - start; em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0); if (IS_ERR(em)) { ret = PTR_ERR(em); goto out; } if (em->block_start == EXTENT_MAP_HOLE) { btrfs_warn(fs_info, "swapfile must not have holes"); ret = -EINVAL; goto out; } if (em->block_start == EXTENT_MAP_INLINE) { /* * It's unlikely we'll ever actually find ourselves * here, as a file small enough to fit inline won't be * big enough to store more than the swap header, but in * case something changes in the future, let's catch it * here rather than later. */ btrfs_warn(fs_info, "swapfile must not be inline"); ret = -EINVAL; goto out; } if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { btrfs_warn(fs_info, "swapfile must not be compressed"); ret = -EINVAL; goto out; } logical_block_start = em->block_start + (start - em->start); len = min(len, em->len - (start - em->start)); free_extent_map(em); em = NULL; ret = can_nocow_extent(inode, start, &len, NULL, NULL, NULL); if (ret < 0) { goto out; } else if (ret) { ret = 0; } else { btrfs_warn(fs_info, "swapfile must not be copy-on-write"); ret = -EINVAL; goto out; } em = btrfs_get_chunk_map(fs_info, logical_block_start, len); if (IS_ERR(em)) { ret = PTR_ERR(em); goto out; } if (em->map_lookup->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { btrfs_warn(fs_info, "swapfile must have single data profile"); ret = -EINVAL; goto out; } if (device == NULL) { device = em->map_lookup->stripes[0].dev; ret = btrfs_add_swapfile_pin(inode, device, false); if (ret == 1) ret = 0; else if (ret) goto out; } else if (device != em->map_lookup->stripes[0].dev) { btrfs_warn(fs_info, "swapfile must be on one device"); ret = -EINVAL; goto out; } physical_block_start = (em->map_lookup->stripes[0].physical + (logical_block_start - em->start)); len = min(len, em->len - (logical_block_start - em->start)); free_extent_map(em); em = NULL; bg = btrfs_lookup_block_group(fs_info, logical_block_start); if (!bg) { btrfs_warn(fs_info, "could not find block group containing swapfile"); ret = -EINVAL; goto out; } ret = btrfs_add_swapfile_pin(inode, bg, true); if (ret) { btrfs_put_block_group(bg); if (ret == 1) ret = 0; else goto out; } if (bsi.block_len && bsi.block_start + bsi.block_len == physical_block_start) { bsi.block_len += len; } else { if (bsi.block_len) { ret = btrfs_add_swap_extent(sis, &bsi); if (ret) goto out; } bsi.start = start; bsi.block_start = physical_block_start; bsi.block_len = len; } start += len; } if (bsi.block_len) ret = btrfs_add_swap_extent(sis, &bsi); out: if (!IS_ERR_OR_NULL(em)) free_extent_map(em); unlock_extent_cached(io_tree, 0, isize - 1, &cached_state); if (ret) btrfs_swap_deactivate(file); clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); if (ret) return ret; if (device) sis->bdev = device->bdev; *span = bsi.highest_ppage - bsi.lowest_ppage + 1; sis->max = bsi.nr_pages; sis->pages = bsi.nr_pages - 1; sis->highest_bit = bsi.nr_pages - 1; return bsi.nr_extents; } #else static void btrfs_swap_deactivate(struct file *file) { } static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file, sector_t *span) { return -EOPNOTSUPP; } #endif static const struct inode_operations btrfs_dir_inode_operations = { .getattr = btrfs_getattr, .lookup = btrfs_lookup, .create = btrfs_create, .unlink = btrfs_unlink, .link = btrfs_link, .mkdir = btrfs_mkdir, .rmdir = btrfs_rmdir, .rename = btrfs_rename2, .symlink = btrfs_symlink, .setattr = btrfs_setattr, .mknod = btrfs_mknod, .listxattr = btrfs_listxattr, .permission = btrfs_permission, .get_acl = btrfs_get_acl, .set_acl = btrfs_set_acl, .update_time = btrfs_update_time, .tmpfile = btrfs_tmpfile, }; static const struct inode_operations btrfs_dir_ro_inode_operations = { .lookup = btrfs_lookup, .permission = btrfs_permission, .update_time = btrfs_update_time, }; static const struct file_operations btrfs_dir_file_operations = { .llseek = generic_file_llseek, .read = generic_read_dir, .iterate_shared = btrfs_real_readdir, .open = btrfs_opendir, .unlocked_ioctl = btrfs_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = btrfs_compat_ioctl, #endif .release = btrfs_release_file, .fsync = btrfs_sync_file, }; static const struct extent_io_ops btrfs_extent_io_ops = { /* mandatory callbacks */ .submit_bio_hook = btrfs_submit_bio_hook, .readpage_end_io_hook = btrfs_readpage_end_io_hook, }; /* * btrfs doesn't support the bmap operation because swapfiles * use bmap to make a mapping of extents in the file. They assume * these extents won't change over the life of the file and they * use the bmap result to do IO directly to the drive. * * the btrfs bmap call would return logical addresses that aren't * suitable for IO and they also will change frequently as COW * operations happen. So, swapfile + btrfs == corruption. * * For now we're avoiding this by dropping bmap. */ static const struct address_space_operations btrfs_aops = { .readpage = btrfs_readpage, .writepage = btrfs_writepage, .writepages = btrfs_writepages, .readpages = btrfs_readpages, .direct_IO = btrfs_direct_IO, .invalidatepage = btrfs_invalidatepage, .releasepage = btrfs_releasepage, .set_page_dirty = btrfs_set_page_dirty, .error_remove_page = generic_error_remove_page, .swap_activate = btrfs_swap_activate, .swap_deactivate = btrfs_swap_deactivate, }; static const struct inode_operations btrfs_file_inode_operations = { .getattr = btrfs_getattr, .setattr = btrfs_setattr, .listxattr = btrfs_listxattr, .permission = btrfs_permission, .fiemap = btrfs_fiemap, .get_acl = btrfs_get_acl, .set_acl = btrfs_set_acl, .update_time = btrfs_update_time, }; static const struct inode_operations btrfs_special_inode_operations = { .getattr = btrfs_getattr, .setattr = btrfs_setattr, .permission = btrfs_permission, .listxattr = btrfs_listxattr, .get_acl = btrfs_get_acl, .set_acl = btrfs_set_acl, .update_time = btrfs_update_time, }; static const struct inode_operations btrfs_symlink_inode_operations = { .get_link = page_get_link, .getattr = btrfs_getattr, .setattr = btrfs_setattr, .permission = btrfs_permission, .listxattr = btrfs_listxattr, .update_time = btrfs_update_time, }; const struct dentry_operations btrfs_dentry_operations = { .d_delete = btrfs_dentry_delete, };