diff options
| -rw-r--r-- | fs/gfs2/bmap.c | 4 | ||||
| -rw-r--r-- | fs/iomap.c | 452 | ||||
| -rw-r--r-- | fs/xfs/xfs_iomap.c | 6 | ||||
| -rw-r--r-- | include/linux/iomap.h | 5 |
4 files changed, 420 insertions, 47 deletions
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index 49a6ab919bd7..89f1f7d3186d 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -890,7 +890,7 @@ unstuff: iomap->addr = be64_to_cpu(*ptr) << inode->i_blkbits; iomap->length = len << inode->i_blkbits; iomap->type = IOMAP_MAPPED; - iomap->flags = IOMAP_F_MERGED; + iomap->flags |= IOMAP_F_MERGED; if (eob) iomap->flags |= IOMAP_F_GFS2_BOUNDARY; @@ -1084,6 +1084,8 @@ static int gfs2_iomap_begin(struct inode *inode, loff_t pos, loff_t length, struct metapath mp = { .mp_aheight = 1, }; int ret; + iomap->flags |= IOMAP_F_BUFFER_HEAD; + trace_gfs2_iomap_start(ip, pos, length, flags); if ((flags & IOMAP_WRITE) && !(flags & IOMAP_DIRECT)) { ret = gfs2_iomap_begin_write(inode, pos, length, flags, iomap); diff --git a/fs/iomap.c b/fs/iomap.c index a1f71e64ea49..13cdcf33e6c0 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -1,6 +1,6 @@ /* * Copyright (C) 2010 Red Hat, Inc. - * Copyright (c) 2016 Christoph Hellwig. + * Copyright (c) 2016-2018 Christoph Hellwig. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, @@ -18,6 +18,7 @@ #include <linux/uaccess.h> #include <linux/gfp.h> #include <linux/mm.h> +#include <linux/mm_inline.h> #include <linux/swap.h> #include <linux/pagemap.h> #include <linux/pagevec.h> @@ -124,6 +125,223 @@ iomap_read_inline_data(struct inode *inode, struct page *page, } static void +iomap_read_end_io(struct bio *bio) +{ + int error = blk_status_to_errno(bio->bi_status); + struct bio_vec *bvec; + int i; + + bio_for_each_segment_all(bvec, bio, i) + page_endio(bvec->bv_page, false, error); + bio_put(bio); +} + +struct iomap_readpage_ctx { + struct page *cur_page; + bool cur_page_in_bio; + bool is_readahead; + struct bio *bio; + struct list_head *pages; +}; + +static loff_t +iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, + struct iomap *iomap) +{ + struct iomap_readpage_ctx *ctx = data; + struct page *page = ctx->cur_page; + unsigned poff = pos & (PAGE_SIZE - 1); + unsigned plen = min_t(loff_t, PAGE_SIZE - poff, length); + bool is_contig = false; + sector_t sector; + + if (iomap->type == IOMAP_INLINE) { + WARN_ON_ONCE(poff); + iomap_read_inline_data(inode, page, iomap); + return PAGE_SIZE; + } + + /* we don't support blocksize < PAGE_SIZE quite yet. */ + WARN_ON_ONCE(pos != page_offset(page)); + WARN_ON_ONCE(plen != PAGE_SIZE); + + if (iomap->type != IOMAP_MAPPED || pos >= i_size_read(inode)) { + zero_user(page, poff, plen); + SetPageUptodate(page); + goto done; + } + + ctx->cur_page_in_bio = true; + + /* + * Try to merge into a previous segment if we can. + */ + sector = iomap_sector(iomap, pos); + if (ctx->bio && bio_end_sector(ctx->bio) == sector) { + if (__bio_try_merge_page(ctx->bio, page, plen, poff)) + goto done; + is_contig = true; + } + + if (!ctx->bio || !is_contig || bio_full(ctx->bio)) { + gfp_t gfp = mapping_gfp_constraint(page->mapping, GFP_KERNEL); + int nr_vecs = (length + PAGE_SIZE - 1) >> PAGE_SHIFT; + + if (ctx->bio) + submit_bio(ctx->bio); + + if (ctx->is_readahead) /* same as readahead_gfp_mask */ + gfp |= __GFP_NORETRY | __GFP_NOWARN; + ctx->bio = bio_alloc(gfp, min(BIO_MAX_PAGES, nr_vecs)); + ctx->bio->bi_opf = REQ_OP_READ; + if (ctx->is_readahead) + ctx->bio->bi_opf |= REQ_RAHEAD; + ctx->bio->bi_iter.bi_sector = sector; + bio_set_dev(ctx->bio, iomap->bdev); + ctx->bio->bi_end_io = iomap_read_end_io; + } + + __bio_add_page(ctx->bio, page, plen, poff); +done: + return plen; +} + +int +iomap_readpage(struct page *page, const struct iomap_ops *ops) +{ + struct iomap_readpage_ctx ctx = { .cur_page = page }; + struct inode *inode = page->mapping->host; + unsigned poff; + loff_t ret; + + WARN_ON_ONCE(page_has_buffers(page)); + + for (poff = 0; poff < PAGE_SIZE; poff += ret) { + ret = iomap_apply(inode, page_offset(page) + poff, + PAGE_SIZE - poff, 0, ops, &ctx, + iomap_readpage_actor); + if (ret <= 0) { + WARN_ON_ONCE(ret == 0); + SetPageError(page); + break; + } + } + + if (ctx.bio) { + submit_bio(ctx.bio); + WARN_ON_ONCE(!ctx.cur_page_in_bio); + } else { + WARN_ON_ONCE(ctx.cur_page_in_bio); + unlock_page(page); + } + + /* + * Just like mpage_readpages and block_read_full_page we always + * return 0 and just mark the page as PageError on errors. This + * should be cleaned up all through the stack eventually. + */ + return 0; +} +EXPORT_SYMBOL_GPL(iomap_readpage); + +static struct page * +iomap_next_page(struct inode *inode, struct list_head *pages, loff_t pos, + loff_t length, loff_t *done) +{ + while (!list_empty(pages)) { + struct page *page = lru_to_page(pages); + + if (page_offset(page) >= (u64)pos + length) + break; + + list_del(&page->lru); + if (!add_to_page_cache_lru(page, inode->i_mapping, page->index, + GFP_NOFS)) + return page; + + /* + * If we already have a page in the page cache at index we are + * done. Upper layers don't care if it is uptodate after the + * readpages call itself as every page gets checked again once + * actually needed. + */ + *done += PAGE_SIZE; + put_page(page); + } + + return NULL; +} + +static loff_t +iomap_readpages_actor(struct inode *inode, loff_t pos, loff_t length, + void *data, struct iomap *iomap) +{ + struct iomap_readpage_ctx *ctx = data; + loff_t done, ret; + + for (done = 0; done < length; done += ret) { + if (ctx->cur_page && ((pos + done) & (PAGE_SIZE - 1)) == 0) { + if (!ctx->cur_page_in_bio) + unlock_page(ctx->cur_page); + put_page(ctx->cur_page); + ctx->cur_page = NULL; + } + if (!ctx->cur_page) { + ctx->cur_page = iomap_next_page(inode, ctx->pages, + pos, length, &done); + if (!ctx->cur_page) + break; + ctx->cur_page_in_bio = false; + } + ret = iomap_readpage_actor(inode, pos + done, length - done, + ctx, iomap); + } + + return done; +} + +int +iomap_readpages(struct address_space *mapping, struct list_head *pages, + unsigned nr_pages, const struct iomap_ops *ops) +{ + struct iomap_readpage_ctx ctx = { + .pages = pages, + .is_readahead = true, + }; + loff_t pos = page_offset(list_entry(pages->prev, struct page, lru)); + loff_t last = page_offset(list_entry(pages->next, struct page, lru)); + loff_t length = last - pos + PAGE_SIZE, ret = 0; + + while (length > 0) { + ret = iomap_apply(mapping->host, pos, length, 0, ops, + &ctx, iomap_readpages_actor); + if (ret <= 0) { + WARN_ON_ONCE(ret == 0); + goto done; + } + pos += ret; + length -= ret; + } + ret = 0; +done: + if (ctx.bio) + submit_bio(ctx.bio); + if (ctx.cur_page) { + if (!ctx.cur_page_in_bio) + unlock_page(ctx.cur_page); + put_page(ctx.cur_page); + } + + /* + * Check that we didn't lose a page due to the arcance calling + * conventions.. + */ + WARN_ON_ONCE(!ret && !list_empty(ctx.pages)); + return ret; +} +EXPORT_SYMBOL_GPL(iomap_readpages); + +static void iomap_write_failed(struct inode *inode, loff_t pos, unsigned len) { loff_t i_size = i_size_read(inode); @@ -137,6 +355,48 @@ iomap_write_failed(struct inode *inode, loff_t pos, unsigned len) } static int +iomap_read_page_sync(struct inode *inode, loff_t block_start, struct page *page, + unsigned poff, unsigned plen, unsigned from, unsigned to, + struct iomap *iomap) +{ + struct bio_vec bvec; + struct bio bio; + + if (iomap->type != IOMAP_MAPPED || block_start >= i_size_read(inode)) { + zero_user_segments(page, poff, from, to, poff + plen); + return 0; + } + + bio_init(&bio, &bvec, 1); + bio.bi_opf = REQ_OP_READ; + bio.bi_iter.bi_sector = iomap_sector(iomap, block_start); + bio_set_dev(&bio, iomap->bdev); + __bio_add_page(&bio, page, plen, poff); + return submit_bio_wait(&bio); +} + +static int +__iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, + struct page *page, struct iomap *iomap) +{ + loff_t block_size = i_blocksize(inode); + loff_t block_start = pos & ~(block_size - 1); + loff_t block_end = (pos + len + block_size - 1) & ~(block_size - 1); + unsigned poff = block_start & (PAGE_SIZE - 1); + unsigned plen = min_t(loff_t, PAGE_SIZE - poff, block_end - block_start); + unsigned from = pos & (PAGE_SIZE - 1), to = from + len; + + WARN_ON_ONCE(i_blocksize(inode) < PAGE_SIZE); + + if (PageUptodate(page)) + return 0; + if (from <= poff && to >= poff + plen) + return 0; + return iomap_read_page_sync(inode, block_start, page, + poff, plen, from, to, iomap); +} + +static int iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags, struct page **pagep, struct iomap *iomap) { @@ -155,9 +415,10 @@ iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags, if (iomap->type == IOMAP_INLINE) iomap_read_inline_data(inode, page, iomap); - else + else if (iomap->flags & IOMAP_F_BUFFER_HEAD) status = __block_write_begin_int(page, pos, len, NULL, iomap); - + else + status = __iomap_write_begin(inode, pos, len, page, iomap); if (unlikely(status)) { unlock_page(page); put_page(page); @@ -170,6 +431,57 @@ iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags, return status; } +int +iomap_set_page_dirty(struct page *page) +{ + struct address_space *mapping = page_mapping(page); + int newly_dirty; + + if (unlikely(!mapping)) + return !TestSetPageDirty(page); + + /* + * Lock out page->mem_cgroup migration to keep PageDirty + * synchronized with per-memcg dirty page counters. + */ + lock_page_memcg(page); + newly_dirty = !TestSetPageDirty(page); + if (newly_dirty) + __set_page_dirty(page, mapping, 0); + unlock_page_memcg(page); + + if (newly_dirty) + __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); + return newly_dirty; +} +EXPORT_SYMBOL_GPL(iomap_set_page_dirty); + +static int +__iomap_write_end(struct inode *inode, loff_t pos, unsigned len, + unsigned copied, struct page *page, struct iomap *iomap) +{ + flush_dcache_page(page); + + /* + * The blocks that were entirely written will now be uptodate, so we + * don't have to worry about a readpage reading them and overwriting a + * partial write. However if we have encountered a short write and only + * partially written into a block, it will not be marked uptodate, so a + * readpage might come in and destroy our partial write. + * + * Do the simplest thing, and just treat any short write to a non + * uptodate page as a zero-length write, and force the caller to redo + * the whole thing. + */ + if (unlikely(copied < len && !PageUptodate(page))) { + copied = 0; + } else { + SetPageUptodate(page); + iomap_set_page_dirty(page); + } + return __generic_write_end(inode, pos, copied, page); +} + static int iomap_write_end_inline(struct inode *inode, struct page *page, struct iomap *iomap, loff_t pos, unsigned copied) @@ -196,9 +508,11 @@ iomap_write_end(struct inode *inode, loff_t pos, unsigned len, if (iomap->type == IOMAP_INLINE) { ret = iomap_write_end_inline(inode, page, iomap, pos, copied); - } else { + } else if (iomap->flags & IOMAP_F_BUFFER_HEAD) { ret = generic_write_end(NULL, inode->i_mapping, pos, len, copied, page, NULL); + } else { + ret = __iomap_write_end(inode, pos, len, copied, page, iomap); } if (iomap->page_done) @@ -491,11 +805,16 @@ iomap_page_mkwrite_actor(struct inode *inode, loff_t pos, loff_t length, struct page *page = data; int ret; - ret = __block_write_begin_int(page, pos, length, NULL, iomap); - if (ret) - return ret; + if (iomap->flags & IOMAP_F_BUFFER_HEAD) { + ret = __block_write_begin_int(page, pos, length, NULL, iomap); + if (ret) + return ret; + block_commit_write(page, 0, length); + } else { + WARN_ON_ONCE(!PageUptodate(page)); + WARN_ON_ONCE(i_blocksize(inode) < PAGE_SIZE); + } - block_commit_write(page, 0, length); return length; } @@ -1014,10 +1333,9 @@ iomap_dio_zero(struct iomap_dio *dio, struct iomap *iomap, loff_t pos, } static loff_t -iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, - void *data, struct iomap *iomap) +iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, + struct iomap_dio *dio, struct iomap *iomap) { - struct iomap_dio *dio = data; unsigned int blkbits = blksize_bits(bdev_logical_block_size(iomap->bdev)); unsigned int fs_block_size = i_blocksize(inode), pad; unsigned int align = iov_iter_alignment(dio->submit.iter); @@ -1031,41 +1349,27 @@ iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, if ((pos | length | align) & ((1 << blkbits) - 1)) return -EINVAL; - switch (iomap->type) { - case IOMAP_HOLE: - if (WARN_ON_ONCE(dio->flags & IOMAP_DIO_WRITE)) - return -EIO; - /*FALLTHRU*/ - case IOMAP_UNWRITTEN: - if (!(dio->flags & IOMAP_DIO_WRITE)) { - length = iov_iter_zero(length, dio->submit.iter); - dio->size += length; - return length; - } + if (iomap->type == IOMAP_UNWRITTEN) { dio->flags |= IOMAP_DIO_UNWRITTEN; need_zeroout = true; - break; - case IOMAP_MAPPED: - if (iomap->flags & IOMAP_F_SHARED) - dio->flags |= IOMAP_DIO_COW; - if (iomap->flags & IOMAP_F_NEW) { - need_zeroout = true; - } else { - /* - * Use a FUA write if we need datasync semantics, this - * is a pure data IO that doesn't require any metadata - * updates and the underlying device supports FUA. This - * allows us to avoid cache flushes on IO completion. - */ - if (!(iomap->flags & (IOMAP_F_SHARED|IOMAP_F_DIRTY)) && - (dio->flags & IOMAP_DIO_WRITE_FUA) && - blk_queue_fua(bdev_get_queue(iomap->bdev))) - use_fua = true; - } - break; - default: - WARN_ON_ONCE(1); - return -EIO; + } + + if (iomap->flags & IOMAP_F_SHARED) + dio->flags |= IOMAP_DIO_COW; + + if (iomap->flags & IOMAP_F_NEW) { + need_zeroout = true; + } else { + /* + * Use a FUA write if we need datasync semantics, this + * is a pure data IO that doesn't require any metadata + * updates and the underlying device supports FUA. This + * allows us to avoid cache flushes on IO completion. + */ + if (!(iomap->flags & (IOMAP_F_SHARED|IOMAP_F_DIRTY)) && + (dio->flags & IOMAP_DIO_WRITE_FUA) && + blk_queue_fua(bdev_get_queue(iomap->bdev))) + use_fua = true; } /* @@ -1144,6 +1448,66 @@ iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, return copied; } +static loff_t +iomap_dio_hole_actor(loff_t length, struct iomap_dio *dio) +{ + length = iov_iter_zero(length, dio->submit.iter); + dio->size += length; + return length; +} + +static loff_t +iomap_dio_inline_actor(struct inode *inode, loff_t pos, loff_t length, + struct iomap_dio *dio, struct iomap *iomap) +{ + struct iov_iter *iter = dio->submit.iter; + size_t copied; + + BUG_ON(pos + length > PAGE_SIZE - offset_in_page(iomap->inline_data)); + + if (dio->flags & IOMAP_DIO_WRITE) { + loff_t size = inode->i_size; + + if (pos > size) + memset(iomap->inline_data + size, 0, pos - size); + copied = copy_from_iter(iomap->inline_data + pos, length, iter); + if (copied) { + if (pos + copied > size) + i_size_write(inode, pos + copied); + mark_inode_dirty(inode); + } + } else { + copied = copy_to_iter(iomap->inline_data + pos, length, iter); + } + dio->size += copied; + return copied; +} + +static loff_t +iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, + void *data, struct iomap *iomap) +{ + struct iomap_dio *dio = data; + + switch (iomap->type) { + case IOMAP_HOLE: + if (WARN_ON_ONCE(dio->flags & IOMAP_DIO_WRITE)) + return -EIO; + return iomap_dio_hole_actor(length, dio); + case IOMAP_UNWRITTEN: + if (!(dio->flags & IOMAP_DIO_WRITE)) + return iomap_dio_hole_actor(length, dio); + return iomap_dio_bio_actor(inode, pos, length, dio, iomap); + case IOMAP_MAPPED: + return iomap_dio_bio_actor(inode, pos, length, dio, iomap); + case IOMAP_INLINE: + return iomap_dio_inline_actor(inode, pos, length, dio, iomap); + default: + WARN_ON_ONCE(1); + return -EIO; + } +} + /* * iomap_dio_rw() always completes O_[D]SYNC writes regardless of whether the IO * is being issued as AIO or not. This allows us to optimise pure data writes diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 49f5492eed3b..8a3613d576af 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -626,7 +626,7 @@ retry: * Flag newly allocated delalloc blocks with IOMAP_F_NEW so we punch * them out if the write happens to fail. */ - iomap->flags = IOMAP_F_NEW; + iomap->flags |= IOMAP_F_NEW; trace_xfs_iomap_alloc(ip, offset, count, 0, &got); done: if (isnullstartblock(got.br_startblock)) @@ -1019,6 +1019,8 @@ xfs_file_iomap_begin( if (XFS_FORCED_SHUTDOWN(mp)) return -EIO; + iomap->flags |= IOMAP_F_BUFFER_HEAD; + if (((flags & (IOMAP_WRITE | IOMAP_DIRECT)) == IOMAP_WRITE) && !IS_DAX(inode) && !xfs_get_extsz_hint(ip)) { /* Reserve delalloc blocks for regular writeback. */ @@ -1119,7 +1121,7 @@ xfs_file_iomap_begin( if (error) return error; - iomap->flags = IOMAP_F_NEW; + iomap->flags |= IOMAP_F_NEW; trace_xfs_iomap_alloc(ip, offset, length, 0, &imap); out_finish: diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 1f36523d448a..5eb9ca8d7ce5 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -30,6 +30,7 @@ struct vm_fault; */ #define IOMAP_F_NEW 0x01 /* blocks have been newly allocated */ #define IOMAP_F_DIRTY 0x02 /* uncommitted metadata */ +#define IOMAP_F_BUFFER_HEAD 0x04 /* file system requires buffer heads */ /* * Flags that only need to be reported for IOMAP_REPORT requests: @@ -99,6 +100,10 @@ struct iomap_ops { ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from, const struct iomap_ops *ops); +int iomap_readpage(struct page *page, const struct iomap_ops *ops); +int iomap_readpages(struct address_space *mapping, struct list_head *pages, + unsigned nr_pages, const struct iomap_ops *ops); +int iomap_set_page_dirty(struct page *page); int iomap_file_dirty(struct inode *inode, loff_t pos, loff_t len, const struct iomap_ops *ops); int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len, |