/* * segment.c - NILFS segment constructor. * * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * Written by Ryusuke Konishi <ryusuke@osrg.net> * */ #include <linux/pagemap.h> #include <linux/buffer_head.h> #include <linux/writeback.h> #include <linux/bio.h> #include <linux/completion.h> #include <linux/blkdev.h> #include <linux/backing-dev.h> #include <linux/freezer.h> #include <linux/kthread.h> #include <linux/crc32.h> #include <linux/pagevec.h> #include "nilfs.h" #include "btnode.h" #include "page.h" #include "segment.h" #include "sufile.h" #include "cpfile.h" #include "ifile.h" #include "seglist.h" #include "segbuf.h" /* * Segment constructor */ #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */ #define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments appended in collection retry loop */ /* Construction mode */ enum { SC_LSEG_SR = 1, /* Make a logical segment having a super root */ SC_LSEG_DSYNC, /* Flush data blocks of a given file and make a logical segment without a super root */ SC_FLUSH_FILE, /* Flush data files, leads to segment writes without creating a checkpoint */ SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without a checkpoint */ }; /* Stage numbers of dirty block collection */ enum { NILFS_ST_INIT = 0, NILFS_ST_GC, /* Collecting dirty blocks for GC */ NILFS_ST_FILE, NILFS_ST_IFILE, NILFS_ST_CPFILE, NILFS_ST_SUFILE, NILFS_ST_DAT, NILFS_ST_SR, /* Super root */ NILFS_ST_DSYNC, /* Data sync blocks */ NILFS_ST_DONE, }; /* State flags of collection */ #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */ #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */ #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED) /* Operations depending on the construction mode and file type */ struct nilfs_sc_operations { int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *, struct inode *); int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *, struct inode *); int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *, struct inode *); void (*write_data_binfo)(struct nilfs_sc_info *, struct nilfs_segsum_pointer *, union nilfs_binfo *); void (*write_node_binfo)(struct nilfs_sc_info *, struct nilfs_segsum_pointer *, union nilfs_binfo *); }; /* * Other definitions */ static void nilfs_segctor_start_timer(struct nilfs_sc_info *); static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int); static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *); static void nilfs_dispose_list(struct nilfs_sb_info *, struct list_head *, int); #define nilfs_cnt32_gt(a, b) \ (typecheck(__u32, a) && typecheck(__u32, b) && \ ((__s32)(b) - (__s32)(a) < 0)) #define nilfs_cnt32_ge(a, b) \ (typecheck(__u32, a) && typecheck(__u32, b) && \ ((__s32)(a) - (__s32)(b) >= 0)) #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a) #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a) /* * Transaction */ static struct kmem_cache *nilfs_transaction_cachep; /** * nilfs_init_transaction_cache - create a cache for nilfs_transaction_info * * nilfs_init_transaction_cache() creates a slab cache for the struct * nilfs_transaction_info. * * Return Value: On success, it returns 0. On error, one of the following * negative error code is returned. * * %-ENOMEM - Insufficient memory available. */ int nilfs_init_transaction_cache(void) { nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache", sizeof(struct nilfs_transaction_info), 0, SLAB_RECLAIM_ACCOUNT, NULL); return (nilfs_transaction_cachep == NULL) ? -ENOMEM : 0; } /** * nilfs_detroy_transaction_cache - destroy the cache for transaction info * * nilfs_destroy_transaction_cache() frees the slab cache for the struct * nilfs_transaction_info. */ void nilfs_destroy_transaction_cache(void) { kmem_cache_destroy(nilfs_transaction_cachep); } static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti) { struct nilfs_transaction_info *cur_ti = current->journal_info; void *save = NULL; if (cur_ti) { if (cur_ti->ti_magic == NILFS_TI_MAGIC) return ++cur_ti->ti_count; else { /* * If journal_info field is occupied by other FS, * it is saved and will be restored on * nilfs_transaction_commit(). */ printk(KERN_WARNING "NILFS warning: journal info from a different " "FS\n"); save = current->journal_info; } } if (!ti) { ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS); if (!ti) return -ENOMEM; ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC; } else { ti->ti_flags = 0; } ti->ti_count = 0; ti->ti_save = save; ti->ti_magic = NILFS_TI_MAGIC; current->journal_info = ti; return 0; } /** * nilfs_transaction_begin - start indivisible file operations. * @sb: super block * @ti: nilfs_transaction_info * @vacancy_check: flags for vacancy rate checks * * nilfs_transaction_begin() acquires a reader/writer semaphore, called * the segment semaphore, to make a segment construction and write tasks * exclusive. The function is used with nilfs_transaction_commit() in pairs. * The region enclosed by these two functions can be nested. To avoid a * deadlock, the semaphore is only acquired or released in the outermost call. * * This function allocates a nilfs_transaction_info struct to keep context * information on it. It is initialized and hooked onto the current task in * the outermost call. If a pre-allocated struct is given to @ti, it is used * instead; othewise a new struct is assigned from a slab. * * When @vacancy_check flag is set, this function will check the amount of * free space, and will wait for the GC to reclaim disk space if low capacity. * * Return Value: On success, 0 is returned. On error, one of the following * negative error code is returned. * * %-ENOMEM - Insufficient memory available. * * %-ENOSPC - No space left on device */ int nilfs_transaction_begin(struct super_block *sb, struct nilfs_transaction_info *ti, int vacancy_check) { struct nilfs_sb_info *sbi; struct the_nilfs *nilfs; int ret = nilfs_prepare_segment_lock(ti); if (unlikely(ret < 0)) return ret; if (ret > 0) return 0; sbi = NILFS_SB(sb); nilfs = sbi->s_nilfs; down_read(&nilfs->ns_segctor_sem); if (vacancy_check && nilfs_near_disk_full(nilfs)) { up_read(&nilfs->ns_segctor_sem); ret = -ENOSPC; goto failed; } return 0; failed: ti = current->journal_info; current->journal_info = ti->ti_save; if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) kmem_cache_free(nilfs_transaction_cachep, ti); return ret; } /** * nilfs_transaction_commit - commit indivisible file operations. * @sb: super block * * nilfs_transaction_commit() releases the read semaphore which is * acquired by nilfs_transaction_begin(). This is only performed * in outermost call of this function. If a commit flag is set, * nilfs_transaction_commit() sets a timer to start the segment * constructor. If a sync flag is set, it starts construction * directly. */ int nilfs_transaction_commit(struct super_block *sb) { struct nilfs_transaction_info *ti = current->journal_info; struct nilfs_sb_info *sbi; struct nilfs_sc_info *sci; int err = 0; BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); ti->ti_flags |= NILFS_TI_COMMIT; if (ti->ti_count > 0) { ti->ti_count--; return 0; } sbi = NILFS_SB(sb); sci = NILFS_SC(sbi); if (sci != NULL) { if (ti->ti_flags & NILFS_TI_COMMIT) nilfs_segctor_start_timer(sci); if (atomic_read(&sbi->s_nilfs->ns_ndirtyblks) > sci->sc_watermark) nilfs_segctor_do_flush(sci, 0); } up_read(&sbi->s_nilfs->ns_segctor_sem); current->journal_info = ti->ti_save; if (ti->ti_flags & NILFS_TI_SYNC) err = nilfs_construct_segment(sb); if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) kmem_cache_free(nilfs_transaction_cachep, ti); return err; } void nilfs_transaction_abort(struct super_block *sb) { struct nilfs_transaction_info *ti = current->journal_info; BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); if (ti->ti_count > 0) { ti->ti_count--; return; } up_read(&NILFS_SB(sb)->s_nilfs->ns_segctor_sem); current->journal_info = ti->ti_save; if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) kmem_cache_free(nilfs_transaction_cachep, ti); } void nilfs_relax_pressure_in_lock(struct super_block *sb) { struct nilfs_sb_info *sbi = NILFS_SB(sb); struct nilfs_sc_info *sci = NILFS_SC(sbi); struct the_nilfs *nilfs = sbi->s_nilfs; if (!sci || !sci->sc_flush_request) return; set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); up_read(&nilfs->ns_segctor_sem); down_write(&nilfs->ns_segctor_sem); if (sci->sc_flush_request && test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) { struct nilfs_transaction_info *ti = current->journal_info; ti->ti_flags |= NILFS_TI_WRITER; nilfs_segctor_do_immediate_flush(sci); ti->ti_flags &= ~NILFS_TI_WRITER; } downgrade_write(&nilfs->ns_segctor_sem); } static void nilfs_transaction_lock(struct nilfs_sb_info *sbi, struct nilfs_transaction_info *ti, int gcflag) { struct nilfs_transaction_info *cur_ti = current->journal_info; WARN_ON(cur_ti); ti->ti_flags = NILFS_TI_WRITER; ti->ti_count = 0; ti->ti_save = cur_ti; ti->ti_magic = NILFS_TI_MAGIC; INIT_LIST_HEAD(&ti->ti_garbage); current->journal_info = ti; for (;;) { down_write(&sbi->s_nilfs->ns_segctor_sem); if (!test_bit(NILFS_SC_PRIOR_FLUSH, &NILFS_SC(sbi)->sc_flags)) break; nilfs_segctor_do_immediate_flush(NILFS_SC(sbi)); up_write(&sbi->s_nilfs->ns_segctor_sem); yield(); } if (gcflag) ti->ti_flags |= NILFS_TI_GC; } static void nilfs_transaction_unlock(struct nilfs_sb_info *sbi) { struct nilfs_transaction_info *ti = current->journal_info; BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); BUG_ON(ti->ti_count > 0); up_write(&sbi->s_nilfs->ns_segctor_sem); current->journal_info = ti->ti_save; if (!list_empty(&ti->ti_garbage)) nilfs_dispose_list(sbi, &ti->ti_garbage, 0); } static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci, struct nilfs_segsum_pointer *ssp, unsigned bytes) { struct nilfs_segment_buffer *segbuf = sci->sc_curseg; unsigned blocksize = sci->sc_super->s_blocksize; void *p; if (unlikely(ssp->offset + bytes > blocksize)) { ssp->offset = 0; BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh, &segbuf->sb_segsum_buffers)); ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh); } p = ssp->bh->b_data + ssp->offset; ssp->offset += bytes; return p; } /** * nilfs_segctor_reset_segment_buffer - reset the current segment buffer * @sci: nilfs_sc_info */ static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci) { struct nilfs_segment_buffer *segbuf = sci->sc_curseg; struct buffer_head *sumbh; unsigned sumbytes; unsigned flags = 0; int err; if (nilfs_doing_gc()) flags = NILFS_SS_GC; err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime); if (unlikely(err)) return err; sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); sumbytes = segbuf->sb_sum.sumbytes; sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes; sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes; sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; return 0; } static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci) { sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs)) return -E2BIG; /* The current segment is filled up (internal code) */ sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg); return nilfs_segctor_reset_segment_buffer(sci); } static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci) { struct nilfs_segment_buffer *segbuf = sci->sc_curseg; int err; if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) { err = nilfs_segctor_feed_segment(sci); if (err) return err; segbuf = sci->sc_curseg; } err = nilfs_segbuf_extend_payload(segbuf, &sci->sc_super_root); if (likely(!err)) segbuf->sb_sum.flags |= NILFS_SS_SR; return err; } /* * Functions for making segment summary and payloads */ static int nilfs_segctor_segsum_block_required( struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp, unsigned binfo_size) { unsigned blocksize = sci->sc_super->s_blocksize; /* Size of finfo and binfo is enough small against blocksize */ return ssp->offset + binfo_size + (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) > blocksize; } static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci, struct inode *inode) { sci->sc_curseg->sb_sum.nfinfo++; sci->sc_binfo_ptr = sci->sc_finfo_ptr; nilfs_segctor_map_segsum_entry( sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo)); if (inode->i_sb && !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); /* skip finfo */ } static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci, struct inode *inode) { struct nilfs_finfo *finfo; struct nilfs_inode_info *ii; struct nilfs_segment_buffer *segbuf; if (sci->sc_blk_cnt == 0) return; ii = NILFS_I(inode); finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr, sizeof(*finfo)); finfo->fi_ino = cpu_to_le64(inode->i_ino); finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt); finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt); finfo->fi_cno = cpu_to_le64(ii->i_cno); segbuf = sci->sc_curseg; segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset + sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1); sci->sc_finfo_ptr = sci->sc_binfo_ptr; sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; } static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci, struct buffer_head *bh, struct inode *inode, unsigned binfo_size) { struct nilfs_segment_buffer *segbuf; int required, err = 0; retry: segbuf = sci->sc_curseg; required = nilfs_segctor_segsum_block_required( sci, &sci->sc_binfo_ptr, binfo_size); if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) { nilfs_segctor_end_finfo(sci, inode); err = nilfs_segctor_feed_segment(sci); if (err) return err; goto retry; } if (unlikely(required)) { err = nilfs_segbuf_extend_segsum(segbuf); if (unlikely(err)) goto failed; } if (sci->sc_blk_cnt == 0) nilfs_segctor_begin_finfo(sci, inode); nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size); /* Substitution to vblocknr is delayed until update_blocknr() */ nilfs_segbuf_add_file_buffer(segbuf, bh); sci->sc_blk_cnt++; failed: return err; } static int nilfs_handle_bmap_error(int err, const char *fname, struct inode *inode, struct super_block *sb) { if (err == -EINVAL) { nilfs_error(sb, fname, "broken bmap (inode=%lu)\n", inode->i_ino); err = -EIO; } return err; } /* * Callback functions that enumerate, mark, and collect dirty blocks */ static int nilfs_collect_file_data(struct nilfs_sc_info *sci, struct buffer_head *bh, struct inode *inode) { int err; err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); if (unlikely(err < 0)) return nilfs_handle_bmap_error(err, __func__, inode, sci->sc_super); err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(struct nilfs_binfo_v)); if (!err) sci->sc_datablk_cnt++; return err; } static int nilfs_collect_file_node(struct nilfs_sc_info *sci, struct buffer_head *bh, struct inode *inode) { int err; err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); if (unlikely(err < 0)) return nilfs_handle_bmap_error(err, __func__, inode, sci->sc_super); return 0; } static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci, struct buffer_head *bh, struct inode *inode) { WARN_ON(!buffer_dirty(bh)); return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); } static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci, struct nilfs_segsum_pointer *ssp, union nilfs_binfo *binfo) { struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry( sci, ssp, sizeof(*binfo_v)); *binfo_v = binfo->bi_v; } static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci, struct nilfs_segsum_pointer *ssp, union nilfs_binfo *binfo) { __le64 *vblocknr = nilfs_segctor_map_segsum_entry( sci, ssp, sizeof(*vblocknr)); *vblocknr = binfo->bi_v.bi_vblocknr; } struct nilfs_sc_operations nilfs_sc_file_ops = { .collect_data = nilfs_collect_file_data, .collect_node = nilfs_collect_file_node, .collect_bmap = nilfs_collect_file_bmap, .write_data_binfo = nilfs_write_file_data_binfo, .write_node_binfo = nilfs_write_file_node_binfo, }; static int nilfs_collect_dat_data(struct nilfs_sc_info *sci, struct buffer_head *bh, struct inode *inode) { int err; err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); if (unlikely(err < 0)) return nilfs_handle_bmap_error(err, __func__, inode, sci->sc_super); err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); if (!err) sci->sc_datablk_cnt++; return err; } static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci, struct buffer_head *bh, struct inode *inode) { WARN_ON(!buffer_dirty(bh)); return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(struct nilfs_binfo_dat)); } static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci, struct nilfs_segsum_pointer *ssp, union nilfs_binfo *binfo) { __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*blkoff)); *blkoff = binfo->bi_dat.bi_blkoff; } static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci, struct nilfs_segsum_pointer *ssp, union nilfs_binfo *binfo) { struct nilfs_binfo_dat *binfo_dat = nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat)); *binfo_dat = binfo->bi_dat; } struct nilfs_sc_operations nilfs_sc_dat_ops = { .collect_data = nilfs_collect_dat_data, .collect_node = nilfs_collect_file_node, .collect_bmap = nilfs_collect_dat_bmap, .write_data_binfo = nilfs_write_dat_data_binfo, .write_node_binfo = nilfs_write_dat_node_binfo, }; struct nilfs_sc_operations nilfs_sc_dsync_ops = { .collect_data = nilfs_collect_file_data, .collect_node = NULL, .collect_bmap = NULL, .write_data_binfo = nilfs_write_file_data_binfo, .write_node_binfo = NULL, }; static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode, struct list_head *listp, size_t nlimit, loff_t start, loff_t end) { struct address_space *mapping = inode->i_mapping; struct pagevec pvec; pgoff_t index = 0, last = ULONG_MAX; size_t ndirties = 0; int i; if (unlikely(start != 0 || end != LLONG_MAX)) { /* * A valid range is given for sync-ing data pages. The * range is rounded to per-page; extra dirty buffers * may be included if blocksize < pagesize. */ index = start >> PAGE_SHIFT; last = end >> PAGE_SHIFT; } pagevec_init(&pvec, 0); repeat: if (unlikely(index > last) || !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, min_t(pgoff_t, last - index, PAGEVEC_SIZE - 1) + 1)) return ndirties; for (i = 0; i < pagevec_count(&pvec); i++) { struct buffer_head *bh, *head; struct page *page = pvec.pages[i]; if (unlikely(page->index > last)) break; if (mapping->host) { lock_page(page); if (!page_has_buffers(page)) create_empty_buffers(page, 1 << inode->i_blkbits, 0); unlock_page(page); } bh = head = page_buffers(page); do { if (!buffer_dirty(bh)) continue; get_bh(bh); list_add_tail(&bh->b_assoc_buffers, listp); ndirties++; if (unlikely(ndirties >= nlimit)) { pagevec_release(&pvec); cond_resched(); return ndirties; } } while (bh = bh->b_this_page, bh != head); } pagevec_release(&pvec); cond_resched(); goto repeat; } static void nilfs_lookup_dirty_node_buffers(struct inode *inode, struct list_head *listp) { struct nilfs_inode_info *ii = NILFS_I(inode); struct address_space *mapping = &ii->i_btnode_cache; struct pagevec pvec; struct buffer_head *bh, *head; unsigned int i; pgoff_t index = 0; pagevec_init(&pvec, 0); while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, PAGEVEC_SIZE)) { for (i = 0; i < pagevec_count(&pvec); i++) { bh = head = page_buffers(pvec.pages[i]); do { if (buffer_dirty(bh)) { get_bh(bh); list_add_tail(&bh->b_assoc_buffers, listp); } bh = bh->b_this_page; } while (bh != head); } pagevec_release(&pvec); cond_resched(); } } static void nilfs_dispose_list(struct nilfs_sb_info *sbi, struct list_head *head, int force) { struct nilfs_inode_info *ii, *n; struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii; unsigned nv = 0; while (!list_empty(head)) { spin_lock(&sbi->s_inode_lock); list_for_each_entry_safe(ii, n, head, i_dirty) { list_del_init(&ii->i_dirty); if (force) { if (unlikely(ii->i_bh)) { brelse(ii->i_bh); ii->i_bh = NULL; } } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) { set_bit(NILFS_I_QUEUED, &ii->i_state); list_add_tail(&ii->i_dirty, &sbi->s_dirty_files); continue; } ivec[nv++] = ii; if (nv == SC_N_INODEVEC) break; } spin_unlock(&sbi->s_inode_lock); for (pii = ivec; nv > 0; pii++, nv--) iput(&(*pii)->vfs_inode); } } static int nilfs_test_metadata_dirty(struct nilfs_sb_info *sbi) { struct the_nilfs *nilfs = sbi->s_nilfs; int ret = 0; if (nilfs_mdt_fetch_dirty(sbi->s_ifile)) ret++; if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile)) ret++; if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile)) ret++; if (ret || nilfs_doing_gc()) if (nilfs_mdt_fetch_dirty(nilfs_dat_inode(nilfs))) ret++; return ret; } static int nilfs_segctor_clean(struct nilfs_sc_info *sci) { return list_empty(&sci->sc_dirty_files) && !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) && list_empty(&sci->sc_cleaning_segments) && (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes)); } static int nilfs_segctor_confirm(struct nilfs_sc_info *sci) { struct nilfs_sb_info *sbi = sci->sc_sbi; int ret = 0; if (nilfs_test_metadata_dirty(sbi)) set_bit(NILFS_SC_DIRTY, &sci->sc_flags); spin_lock(&sbi->s_inode_lock); if (list_empty(&sbi->s_dirty_files) && nilfs_segctor_clean(sci)) ret++; spin_unlock(&sbi->s_inode_lock); return ret; } static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci) { struct nilfs_sb_info *sbi = sci->sc_sbi; struct the_nilfs *nilfs = sbi->s_nilfs; nilfs_mdt_clear_dirty(sbi->s_ifile); nilfs_mdt_clear_dirty(nilfs->ns_cpfile); nilfs_mdt_clear_dirty(nilfs->ns_sufile); nilfs_mdt_clear_dirty(nilfs_dat_inode(nilfs)); } static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci) { struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs; struct buffer_head *bh_cp; struct nilfs_checkpoint *raw_cp; int err; /* XXX: this interface will be changed */ err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1, &raw_cp, &bh_cp); if (likely(!err)) { /* The following code is duplicated with cpfile. But, it is needed to collect the checkpoint even if it was not newly created */ nilfs_mdt_mark_buffer_dirty(bh_cp); nilfs_mdt_mark_dirty(nilfs->ns_cpfile); nilfs_cpfile_put_checkpoint( nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); } else WARN_ON(err == -EINVAL || err == -ENOENT); return err; } static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci) { struct nilfs_sb_info *sbi = sci->sc_sbi; struct the_nilfs *nilfs = sbi->s_nilfs; struct buffer_head *bh_cp; struct nilfs_checkpoint *raw_cp; int err; err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0, &raw_cp, &bh_cp); if (unlikely(err)) { WARN_ON(err == -EINVAL || err == -ENOENT); goto failed_ibh; } raw_cp->cp_snapshot_list.ssl_next = 0; raw_cp->cp_snapshot_list.ssl_prev = 0; raw_cp->cp_inodes_count = cpu_to_le64(atomic_read(&sbi->s_inodes_count)); raw_cp->cp_blocks_count = cpu_to_le64(atomic_read(&sbi->s_blocks_count)); raw_cp->cp_nblk_inc = cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc); raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime); raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno); if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) nilfs_checkpoint_clear_minor(raw_cp); else nilfs_checkpoint_set_minor(raw_cp); nilfs_write_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode, 1); nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); return 0; failed_ibh: return err; } static void nilfs_fill_in_file_bmap(struct inode *ifile, struct nilfs_inode_info *ii) { struct buffer_head *ibh; struct nilfs_inode *raw_inode; if (test_bit(NILFS_I_BMAP, &ii->i_state)) { ibh = ii->i_bh; BUG_ON(!ibh); raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino, ibh); nilfs_bmap_write(ii->i_bmap, raw_inode); nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh); } } static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci, struct inode *ifile) { struct nilfs_inode_info *ii; list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) { nilfs_fill_in_file_bmap(ifile, ii); set_bit(NILFS_I_COLLECTED, &ii->i_state); } } /* * CRC calculation routines */ static void nilfs_fill_in_super_root_crc(struct buffer_head *bh_sr, u32 seed) { struct nilfs_super_root *raw_sr = (struct nilfs_super_root *)bh_sr->b_data; u32 crc; crc = crc32_le(seed, (unsigned char *)raw_sr + sizeof(raw_sr->sr_sum), NILFS_SR_BYTES - sizeof(raw_sr->sr_sum)); raw_sr->sr_sum = cpu_to_le32(crc); } static void nilfs_segctor_fill_in_checksums(struct nilfs_sc_info *sci, u32 seed) { struct nilfs_segment_buffer *segbuf; if (sci->sc_super_root) nilfs_fill_in_super_root_crc(sci->sc_super_root, seed); list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { nilfs_segbuf_fill_in_segsum_crc(segbuf, seed); nilfs_segbuf_fill_in_data_crc(segbuf, seed); } } static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci, struct the_nilfs *nilfs) { struct buffer_head *bh_sr = sci->sc_super_root; struct nilfs_super_root *raw_sr = (struct nilfs_super_root *)bh_sr->b_data; unsigned isz = nilfs->ns_inode_size; raw_sr->sr_bytes = cpu_to_le16(NILFS_SR_BYTES); raw_sr->sr_nongc_ctime = cpu_to_le64(nilfs_doing_gc() ? nilfs->ns_nongc_ctime : sci->sc_seg_ctime); raw_sr->sr_flags = 0; nilfs_mdt_write_inode_direct( nilfs_dat_inode(nilfs), bh_sr, NILFS_SR_DAT_OFFSET(isz)); nilfs_mdt_write_inode_direct( nilfs->ns_cpfile, bh_sr, NILFS_SR_CPFILE_OFFSET(isz)); nilfs_mdt_write_inode_direct( nilfs->ns_sufile, bh_sr, NILFS_SR_SUFILE_OFFSET(isz)); } static void nilfs_redirty_inodes(struct list_head *head) { struct nilfs_inode_info *ii; list_for_each_entry(ii, head, i_dirty) { if (test_bit(NILFS_I_COLLECTED, &ii->i_state)) clear_bit(NILFS_I_COLLECTED, &ii->i_state); } } static void nilfs_drop_collected_inodes(struct list_head *head) { struct nilfs_inode_info *ii; list_for_each_entry(ii, head, i_dirty) { if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state)) continue; clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state); set_bit(NILFS_I_UPDATED, &ii->i_state); } } static void nilfs_segctor_cancel_free_segments(struct nilfs_sc_info *sci, struct inode *sufile) { struct list_head *head = &sci->sc_cleaning_segments; struct nilfs_segment_entry *ent; int err; list_for_each_entry(ent, head, list) { if (!(ent->flags & NILFS_SLH_FREED)) break; err = nilfs_sufile_cancel_free(sufile, ent->segnum); WARN_ON(err); /* do not happen */ ent->flags &= ~NILFS_SLH_FREED; } } static int nilfs_segctor_prepare_free_segments(struct nilfs_sc_info *sci, struct inode *sufile) { struct list_head *head = &sci->sc_cleaning_segments; struct nilfs_segment_entry *ent; int err; list_for_each_entry(ent, head, list) { err = nilfs_sufile_free(sufile, ent->segnum); if (unlikely(err)) return err; ent->flags |= NILFS_SLH_FREED; } return 0; } static void nilfs_segctor_commit_free_segments(struct nilfs_sc_info *sci) { nilfs_dispose_segment_list(&sci->sc_cleaning_segments); } static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci, struct inode *inode, struct list_head *listp, int (*collect)(struct nilfs_sc_info *, struct buffer_head *, struct inode *)) { struct buffer_head *bh, *n; int err = 0; if (collect) { list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) { list_del_init(&bh->b_assoc_buffers); err = collect(sci, bh, inode); brelse(bh); if (unlikely(err)) goto dispose_buffers; } return 0; } dispose_buffers: while (!list_empty(listp)) { bh = list_entry(listp->next, struct buffer_head, b_assoc_buffers); list_del_init(&bh->b_assoc_buffers); brelse(bh); } return err; } static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci) { /* Remaining number of blocks within segment buffer */ return sci->sc_segbuf_nblocks - (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks); } static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci, struct inode *inode, struct nilfs_sc_operations *sc_ops) { LIST_HEAD(data_buffers); LIST_HEAD(node_buffers); int err; if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { size_t n, rest = nilfs_segctor_buffer_rest(sci); n = nilfs_lookup_dirty_data_buffers( inode, &data_buffers, rest + 1, 0, LLONG_MAX); if (n > rest) { err = nilfs_segctor_apply_buffers( sci, inode, &data_buffers, sc_ops->collect_data); BUG_ON(!err); /* always receive -E2BIG or true error */ goto break_or_fail; } } nilfs_lookup_dirty_node_buffers(inode, &node_buffers); if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { err = nilfs_segctor_apply_buffers( sci, inode, &data_buffers, sc_ops->collect_data); if (unlikely(err)) { /* dispose node list */ nilfs_segctor_apply_buffers( sci, inode, &node_buffers, NULL); goto break_or_fail; } sci->sc_stage.flags |= NILFS_CF_NODE; } /* Collect node */ err = nilfs_segctor_apply_buffers( sci, inode, &node_buffers, sc_ops->collect_node); if (unlikely(err)) goto break_or_fail; nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers); err = nilfs_segctor_apply_buffers( sci, inode, &node_buffers, sc_ops->collect_bmap); if (unlikely(err)) goto break_or_fail; nilfs_segctor_end_finfo(sci, inode); sci->sc_stage.flags &= ~NILFS_CF_NODE; break_or_fail: return err; } static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci, struct inode *inode) { LIST_HEAD(data_buffers); size_t n, rest = nilfs_segctor_buffer_rest(sci); int err; n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1, sci->sc_dsync_start, sci->sc_dsync_end); err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers, nilfs_collect_file_data); if (!err) { nilfs_segctor_end_finfo(sci, inode); BUG_ON(n > rest); /* always receive -E2BIG or true error if n > rest */ } return err; } static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode) { struct nilfs_sb_info *sbi = sci->sc_sbi; struct the_nilfs *nilfs = sbi->s_nilfs; struct list_head *head; struct nilfs_inode_info *ii; int err = 0; switch (sci->sc_stage.scnt) { case NILFS_ST_INIT: /* Pre-processes */ sci->sc_stage.flags = 0; if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) { sci->sc_nblk_inc = 0; sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN; if (mode == SC_LSEG_DSYNC) { sci->sc_stage.scnt = NILFS_ST_DSYNC; goto dsync_mode; } } sci->sc_stage.dirty_file_ptr = NULL; sci->sc_stage.gc_inode_ptr = NULL; if (mode == SC_FLUSH_DAT) { sci->sc_stage.scnt = NILFS_ST_DAT; goto dat_stage; } sci->sc_stage.scnt++; /* Fall through */ case NILFS_ST_GC: if (nilfs_doing_gc()) { head = &sci->sc_gc_inodes; ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr, head, i_dirty); list_for_each_entry_continue(ii, head, i_dirty) { err = nilfs_segctor_scan_file( sci, &ii->vfs_inode, &nilfs_sc_file_ops); if (unlikely(err)) { sci->sc_stage.gc_inode_ptr = list_entry( ii->i_dirty.prev, struct nilfs_inode_info, i_dirty); goto break_or_fail; } set_bit(NILFS_I_COLLECTED, &ii->i_state); } sci->sc_stage.gc_inode_ptr = NULL; } sci->sc_stage.scnt++; /* Fall through */ case NILFS_ST_FILE: head = &sci->sc_dirty_files; ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head, i_dirty); list_for_each_entry_continue(ii, head, i_dirty) { clear_bit(NILFS_I_DIRTY, &ii->i_state); err = nilfs_segctor_scan_file(sci, &ii->vfs_inode, &nilfs_sc_file_ops); if (unlikely(err)) { sci->sc_stage.dirty_file_ptr = list_entry(ii->i_dirty.prev, struct nilfs_inode_info, i_dirty); goto break_or_fail; } /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */ /* XXX: required ? */ } sci->sc_stage.dirty_file_ptr = NULL; if (mode == SC_FLUSH_FILE) { sci->sc_stage.scnt = NILFS_ST_DONE; return 0; } sci->sc_stage.scnt++; sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED; /* Fall through */ case NILFS_ST_IFILE: err = nilfs_segctor_scan_file(sci, sbi->s_ifile, &nilfs_sc_file_ops); if (unlikely(err)) break; sci->sc_stage.scnt++; /* Creating a checkpoint */ err = nilfs_segctor_create_checkpoint(sci); if (unlikely(err)) break; /* Fall through */ case NILFS_ST_CPFILE: err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile, &nilfs_sc_file_ops); if (unlikely(err)) break; sci->sc_stage.scnt++; /* Fall through */ case NILFS_ST_SUFILE: err = nilfs_segctor_prepare_free_segments(sci, nilfs->ns_sufile); if (unlikely(err)) break; err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile, &nilfs_sc_file_ops); if (unlikely(err)) break; sci->sc_stage.scnt++; /* Fall through */ case NILFS_ST_DAT: dat_stage: err = nilfs_segctor_scan_file(sci, nilfs_dat_inode(nilfs), &nilfs_sc_dat_ops); if (unlikely(err)) break; if (mode == SC_FLUSH_DAT) { sci->sc_stage.scnt = NILFS_ST_DONE; return 0; } sci->sc_stage.scnt++; /* Fall through */ case NILFS_ST_SR: if (mode == SC_LSEG_SR) { /* Appending a super root */ err = nilfs_segctor_add_super_root(sci); if (unlikely(err)) break; } /* End of a logical segment */ sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; sci->sc_stage.scnt = NILFS_ST_DONE; return 0; case NILFS_ST_DSYNC: dsync_mode: sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT; ii = sci->sc_dsync_inode; if (!test_bit(NILFS_I_BUSY, &ii->i_state)) break; err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode); if (unlikely(err)) break; sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; sci->sc_stage.scnt = NILFS_ST_DONE; return 0; case NILFS_ST_DONE: return 0; default: BUG(); } break_or_fail: return err; } static int nilfs_touch_segusage(struct inode *sufile, __u64 segnum) { struct buffer_head *bh_su; struct nilfs_segment_usage *raw_su; int err; err = nilfs_sufile_get_segment_usage(sufile, segnum, &raw_su, &bh_su); if (unlikely(err)) return err; nilfs_mdt_mark_buffer_dirty(bh_su); nilfs_mdt_mark_dirty(sufile); nilfs_sufile_put_segment_usage(sufile, segnum, bh_su); return 0; } static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci, struct the_nilfs *nilfs) { struct nilfs_segment_buffer *segbuf, *n; __u64 nextnum; int err; if (list_empty(&sci->sc_segbufs)) { segbuf = nilfs_segbuf_new(sci->sc_super); if (unlikely(!segbuf)) return -ENOMEM; list_add(&segbuf->sb_list, &sci->sc_segbufs); } else segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); nilfs_segbuf_map(segbuf, nilfs->ns_segnum, nilfs->ns_pseg_offset, nilfs); if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { nilfs_shift_to_next_segment(nilfs); nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs); } sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks; err = nilfs_touch_segusage(nilfs->ns_sufile, segbuf->sb_segnum); if (unlikely(err)) return err; if (nilfs->ns_segnum == nilfs->ns_nextnum) { /* Start from the head of a new full segment */ err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum); if (unlikely(err)) return err; } else nextnum = nilfs->ns_nextnum; segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq; nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs); /* truncating segment buffers */ list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs, sb_list) { list_del_init(&segbuf->sb_list); nilfs_segbuf_free(segbuf); } return 0; } static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci, struct the_nilfs *nilfs, int nadd) { struct nilfs_segment_buffer *segbuf, *prev, *n; struct inode *sufile = nilfs->ns_sufile; __u64 nextnextnum; LIST_HEAD(list); int err, ret, i; prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs); /* * Since the segment specified with nextnum might be allocated during * the previous construction, the buffer including its segusage may * not be dirty. The following call ensures that the buffer is dirty * and will pin the buffer on memory until the sufile is written. */ err = nilfs_touch_segusage(sufile, prev->sb_nextnum); if (unlikely(err)) return err; for (i = 0; i < nadd; i++) { /* extend segment info */ err = -ENOMEM; segbuf = nilfs_segbuf_new(sci->sc_super); if (unlikely(!segbuf)) goto failed; /* map this buffer to region of segment on-disk */ nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks; /* allocate the next next full segment */ err = nilfs_sufile_alloc(sufile, &nextnextnum); if (unlikely(err)) goto failed_segbuf; segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1; nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs); list_add_tail(&segbuf->sb_list, &list); prev = segbuf; } list_splice(&list, sci->sc_segbufs.prev); return 0; failed_segbuf: nilfs_segbuf_free(segbuf); failed: list_for_each_entry_safe(segbuf, n, &list, sb_list) { ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); WARN_ON(ret); /* never fails */ list_del_init(&segbuf->sb_list); nilfs_segbuf_free(segbuf); } return err; } static void nilfs_segctor_free_incomplete_segments(struct nilfs_sc_info *sci, struct the_nilfs *nilfs) { struct nilfs_segment_buffer *segbuf; int ret, done = 0; segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); if (nilfs->ns_nextnum != segbuf->sb_nextnum) { ret = nilfs_sufile_free(nilfs->ns_sufile, segbuf->sb_nextnum); WARN_ON(ret); /* never fails */ } if (segbuf->sb_io_error) { /* Case 1: The first segment failed */ if (segbuf->sb_pseg_start != segbuf->sb_fseg_start) /* Case 1a: Partial segment appended into an existing segment */ nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start, segbuf->sb_fseg_end); else /* Case 1b: New full segment */ set_nilfs_discontinued(nilfs); done++; } list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { ret = nilfs_sufile_free(nilfs->ns_sufile, segbuf->sb_nextnum); WARN_ON(ret); /* never fails */ if (!done && segbuf->sb_io_error) { if (segbuf->sb_segnum != nilfs->ns_nextnum) /* Case 2: extended segment (!= next) failed */ nilfs_sufile_set_error(nilfs->ns_sufile, segbuf->sb_segnum); done++; } } } static void nilfs_segctor_clear_segment_buffers(struct nilfs_sc_info *sci) { struct nilfs_segment_buffer *segbuf; list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) nilfs_segbuf_clear(segbuf); sci->sc_super_root = NULL; } static void nilfs_segctor_destroy_segment_buffers(struct nilfs_sc_info *sci) { struct nilfs_segment_buffer *segbuf; while (!list_empty(&sci->sc_segbufs)) { segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); list_del_init(&segbuf->sb_list); nilfs_segbuf_free(segbuf); } /* sci->sc_curseg = NULL; */ } static void nilfs_segctor_end_construction(struct nilfs_sc_info *sci, struct the_nilfs *nilfs, int err) { if (unlikely(err)) { nilfs_segctor_free_incomplete_segments(sci, nilfs); nilfs_segctor_cancel_free_segments(sci, nilfs->ns_sufile); } nilfs_segctor_clear_segment_buffers(sci); } static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci, struct inode *sufile) { struct nilfs_segment_buffer *segbuf; struct buffer_head *bh_su; struct nilfs_segment_usage *raw_su; unsigned long live_blocks; int ret; list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum, &raw_su, &bh_su); WARN_ON(ret); /* always succeed because bh_su is dirty */ live_blocks = segbuf->sb_sum.nblocks + (segbuf->sb_pseg_start - segbuf->sb_fseg_start); raw_su->su_lastmod = cpu_to_le64(sci->sc_seg_ctime); raw_su->su_nblocks = cpu_to_le32(live_blocks); nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum, bh_su); } } static void nilfs_segctor_cancel_segusage(struct nilfs_sc_info *sci, struct inode *sufile) { struct nilfs_segment_buffer *segbuf; struct buffer_head *bh_su; struct nilfs_segment_usage *raw_su; int ret; segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum, &raw_su, &bh_su); WARN_ON(ret); /* always succeed because bh_su is dirty */ raw_su->su_nblocks = cpu_to_le32(segbuf->sb_pseg_start - segbuf->sb_fseg_start); nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum, bh_su); list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum, &raw_su, &bh_su); WARN_ON(ret); /* always succeed */ raw_su->su_nblocks = 0; nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum, bh_su); } } static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci, struct nilfs_segment_buffer *last, struct inode *sufile) { struct nilfs_segment_buffer *segbuf = last, *n; int ret; list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs, sb_list) { list_del_init(&segbuf->sb_list); sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks; ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); WARN_ON(ret); nilfs_segbuf_free(segbuf); } } static int nilfs_segctor_collect(struct nilfs_sc_info *sci, struct the_nilfs *nilfs, int mode) { struct nilfs_cstage prev_stage = sci->sc_stage; int err, nadd = 1; /* Collection retry loop */ for (;;) { sci->sc_super_root = NULL; sci->sc_nblk_this_inc = 0; sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); err = nilfs_segctor_reset_segment_buffer(sci); if (unlikely(err)) goto failed; err = nilfs_segctor_collect_blocks(sci, mode); sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; if (!err) break; if (unlikely(err != -E2BIG)) goto failed; /* The current segment is filled up */ if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE) break; nilfs_segctor_cancel_free_segments(sci, nilfs->ns_sufile); nilfs_segctor_clear_segment_buffers(sci); err = nilfs_segctor_extend_segments(sci, nilfs, nadd); if (unlikely(err)) return err; nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA); sci->sc_stage = prev_stage; } nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile); return 0; failed: return err; } static void nilfs_list_replace_buffer(struct buffer_head *old_bh, struct buffer_head *new_bh) { BUG_ON(!list_empty(&new_bh->b_assoc_buffers)); list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers); /* The caller must release old_bh */ } static int nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci, struct nilfs_segment_buffer *segbuf, int mode) { struct inode *inode = NULL; sector_t blocknr; unsigned long nfinfo = segbuf->sb_sum.nfinfo; unsigned long nblocks = 0, ndatablk = 0; struct nilfs_sc_operations *sc_op = NULL; struct nilfs_segsum_pointer ssp; struct nilfs_finfo *finfo = NULL; union nilfs_binfo binfo; struct buffer_head *bh, *bh_org; ino_t ino = 0; int err = 0; if (!nfinfo) goto out; blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk; ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); ssp.offset = sizeof(struct nilfs_segment_summary); list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { if (bh == sci->sc_super_root) break; if (!finfo) { finfo = nilfs_segctor_map_segsum_entry( sci, &ssp, sizeof(*finfo)); ino = le64_to_cpu(finfo->fi_ino); nblocks = le32_to_cpu(finfo->fi_nblocks); ndatablk = le32_to_cpu(finfo->fi_ndatablk); if (buffer_nilfs_node(bh)) inode = NILFS_BTNC_I(bh->b_page->mapping); else inode = NILFS_AS_I(bh->b_page->mapping); if (mode == SC_LSEG_DSYNC) sc_op = &nilfs_sc_dsync_ops; else if (ino == NILFS_DAT_INO) sc_op = &nilfs_sc_dat_ops; else /* file blocks */ sc_op = &nilfs_sc_file_ops; } bh_org = bh; get_bh(bh_org); err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr, &binfo); if (bh != bh_org) nilfs_list_replace_buffer(bh_org, bh); brelse(bh_org); if (unlikely(err)) goto failed_bmap; if (ndatablk > 0) sc_op->write_data_binfo(sci, &ssp, &binfo); else sc_op->write_node_binfo(sci, &ssp, &binfo); blocknr++; if (--nblocks == 0) { finfo = NULL; if (--nfinfo == 0) break; } else if (ndatablk > 0) ndatablk--; } out: return 0; failed_bmap: err = nilfs_handle_bmap_error(err, __func__, inode, sci->sc_super); return err; } static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode) { struct nilfs_segment_buffer *segbuf; int err; list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode); if (unlikely(err)) return err; nilfs_segbuf_fill_in_segsum(segbuf); } return 0; } static int nilfs_copy_replace_page_buffers(struct page *page, struct list_head *out) { struct page *clone_page; struct buffer_head *bh, *head, *bh2; void *kaddr; bh = head = page_buffers(page); clone_page = nilfs_alloc_private_page(bh->b_bdev, bh->b_size, 0); if (unlikely(!clone_page)) return -ENOMEM; bh2 = page_buffers(clone_page); kaddr = kmap_atomic(page, KM_USER0); do { if (list_empty(&bh->b_assoc_buffers)) continue; get_bh(bh2); page_cache_get(clone_page); /* for each bh */ memcpy(bh2->b_data, kaddr + bh_offset(bh), bh2->b_size); bh2->b_blocknr = bh->b_blocknr; list_replace(&bh->b_assoc_buffers, &bh2->b_assoc_buffers); list_add_tail(&bh->b_assoc_buffers, out); } while (bh = bh->b_this_page, bh2 = bh2->b_this_page, bh != head); kunmap_atomic(kaddr, KM_USER0); if (!TestSetPageWriteback(clone_page)) inc_zone_page_state(clone_page, NR_WRITEBACK); unlock_page(clone_page); return 0; } static int nilfs_test_page_to_be_frozen(struct page *page) { struct address_space *mapping = page->mapping; if (!mapping || !mapping->host || S_ISDIR(mapping->host->i_mode)) return 0; if (page_mapped(page)) { ClearPageChecked(page); return 1; } return PageChecked(page); } static int nilfs_begin_page_io(struct page *page, struct list_head *out) { if (!page || PageWriteback(page)) /* For split b-tree node pages, this function may be called twice. We ignore the 2nd or later calls by this check. */ return 0; lock_page(page); clear_page_dirty_for_io(page); set_page_writeback(page); unlock_page(page); if (nilfs_test_page_to_be_frozen(page)) { int err = nilfs_copy_replace_page_buffers(page, out); if (unlikely(err)) return err; } return 0; } static int nilfs_segctor_prepare_write(struct nilfs_sc_info *sci, struct page **failed_page) { struct nilfs_segment_buffer *segbuf; struct page *bd_page = NULL, *fs_page = NULL; struct list_head *list = &sci->sc_copied_buffers; int err; *failed_page = NULL; list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { struct buffer_head *bh; list_for_each_entry(bh, &segbuf->sb_segsum_buffers, b_assoc_buffers) { if (bh->b_page != bd_page) { if (bd_page) { lock_page(bd_page); clear_page_dirty_for_io(bd_page); set_page_writeback(bd_page); unlock_page(bd_page); } bd_page = bh->b_page; } } list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { if (bh == sci->sc_super_root) { if (bh->b_page != bd_page) { lock_page(bd_page); clear_page_dirty_for_io(bd_page); set_page_writeback(bd_page); unlock_page(bd_page); bd_page = bh->b_page; } break; } if (bh->b_page != fs_page) { err = nilfs_begin_page_io(fs_page, list); if (unlikely(err)) { *failed_page = fs_page; goto out; } fs_page = bh->b_page; } } } if (bd_page) { lock_page(bd_page); clear_page_dirty_for_io(bd_page); set_page_writeback(bd_page); unlock_page(bd_page); } err = nilfs_begin_page_io(fs_page, list); if (unlikely(err)) *failed_page = fs_page; out: return err; } static int nilfs_segctor_write(struct nilfs_sc_info *sci, struct backing_dev_info *bdi) { struct nilfs_segment_buffer *segbuf; struct nilfs_write_info wi; int err, res; wi.sb = sci->sc_super; wi.bh_sr = sci->sc_super_root; wi.bdi = bdi; list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { nilfs_segbuf_prepare_write(segbuf, &wi); err = nilfs_segbuf_write(segbuf, &wi); res = nilfs_segbuf_wait(segbuf, &wi); err = unlikely(err) ? : res; if (unlikely(err)) return err; } return 0; } static int nilfs_page_has_uncleared_buffer(struct page *page) { struct buffer_head *head, *bh; head = bh = page_buffers(page); do { if (buffer_dirty(bh) && !list_empty(&bh->b_assoc_buffers)) return 1; bh = bh->b_this_page; } while (bh != head); return 0; } static void __nilfs_end_page_io(struct page *page, int err) { if (!err) { if (!nilfs_page_buffers_clean(page)) __set_page_dirty_nobuffers(page); ClearPageError(page); } else { __set_page_dirty_nobuffers(page); SetPageError(page); } if (buffer_nilfs_allocated(page_buffers(page))) { if (TestClearPageWriteback(page)) dec_zone_page_state(page, NR_WRITEBACK); } else end_page_writeback(page); } static void nilfs_end_page_io(struct page *page, int err) { if (!page) return; if (buffer_nilfs_node(page_buffers(page)) && nilfs_page_has_uncleared_buffer(page)) /* For b-tree node pages, this function may be called twice or more because they might be split in a segment. This check assures that cleanup has been done for all buffers in a split btnode page. */ return; __nilfs_end_page_io(page, err); } static void nilfs_clear_copied_buffers(struct list_head *list, int err) { struct buffer_head *bh, *head; struct page *page; while (!list_empty(list)) { bh = list_entry(list->next, struct buffer_head, b_assoc_buffers); page = bh->b_page; page_cache_get(page); head = bh = page_buffers(page); do { if (!list_empty(&bh->b_assoc_buffers)) { list_del_init(&bh->b_assoc_buffers); if (!err) { set_buffer_uptodate(bh); clear_buffer_dirty(bh); clear_buffer_nilfs_volatile(bh); } brelse(bh); /* for b_assoc_buffers */ } } while ((bh = bh->b_this_page) != head); __nilfs_end_page_io(page, err); page_cache_release(page); } } static void nilfs_segctor_abort_write(struct nilfs_sc_info *sci, struct page *failed_page, int err) { struct nilfs_segment_buffer *segbuf; struct page *bd_page = NULL, *fs_page = NULL; list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { struct buffer_head *bh; list_for_each_entry(bh, &segbuf->sb_segsum_buffers, b_assoc_buffers) { if (bh->b_page != bd_page) { if (bd_page) end_page_writeback(bd_page); bd_page = bh->b_page; } } list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { if (bh == sci->sc_super_root) { if (bh->b_page != bd_page) { end_page_writeback(bd_page); bd_page = bh->b_page; } break; } if (bh->b_page != fs_page) { nilfs_end_page_io(fs_page, err); if (unlikely(fs_page == failed_page)) goto done; fs_page = bh->b_page; } } } if (bd_page) end_page_writeback(bd_page); nilfs_end_page_io(fs_page, err); done: nilfs_clear_copied_buffers(&sci->sc_copied_buffers, err); } static void nilfs_set_next_segment(struct the_nilfs *nilfs, struct nilfs_segment_buffer *segbuf) { nilfs->ns_segnum = segbuf->sb_segnum; nilfs->ns_nextnum = segbuf->sb_nextnum; nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start + segbuf->sb_sum.nblocks; nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq; nilfs->ns_ctime = segbuf->sb_sum.ctime; } static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci) { struct nilfs_segment_buffer *segbuf; struct page *bd_page = NULL, *fs_page = NULL; struct nilfs_sb_info *sbi = sci->sc_sbi; struct the_nilfs *nilfs = sbi->s_nilfs; int update_sr = (sci->sc_super_root != NULL); list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { struct buffer_head *bh; list_for_each_entry(bh, &segbuf->sb_segsum_buffers, b_assoc_buffers) { set_buffer_uptodate(bh); clear_buffer_dirty(bh); if (bh->b_page != bd_page) { if (bd_page) end_page_writeback(bd_page); bd_page = bh->b_page; } } /* * We assume that the buffers which belong to the same page * continue over the buffer list. * Under this assumption, the last BHs of pages is * identifiable by the discontinuity of bh->b_page * (page != fs_page). * * For B-tree node blocks, however, this assumption is not * guaranteed. The cleanup code of B-tree node pages needs * special care. */ list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { set_buffer_uptodate(bh); clear_buffer_dirty(bh); clear_buffer_nilfs_volatile(bh); if (bh == sci->sc_super_root) { if (bh->b_page != bd_page) { end_page_writeback(bd_page); bd_page = bh->b_page; } break; } if (bh->b_page != fs_page) { nilfs_end_page_io(fs_page, 0); fs_page = bh->b_page; } } if (!NILFS_SEG_SIMPLEX(&segbuf->sb_sum)) { if (NILFS_SEG_LOGBGN(&segbuf->sb_sum)) { set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); sci->sc_lseg_stime = jiffies; } if (NILFS_SEG_LOGEND(&segbuf->sb_sum)) clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); } } /* * Since pages may continue over multiple segment buffers, * end of the last page must be checked outside of the loop. */ if (bd_page) end_page_writeback(bd_page); nilfs_end_page_io(fs_page, 0); nilfs_clear_copied_buffers(&sci->sc_copied_buffers, 0); nilfs_drop_collected_inodes(&sci->sc_dirty_files); if (nilfs_doing_gc()) { nilfs_drop_collected_inodes(&sci->sc_gc_inodes); if (update_sr) nilfs_commit_gcdat_inode(nilfs); } else nilfs->ns_nongc_ctime = sci->sc_seg_ctime; sci->sc_nblk_inc += sci->sc_nblk_this_inc; segbuf = NILFS_LAST_SEGBUF(&sci->sc_segbufs); nilfs_set_next_segment(nilfs, segbuf); if (update_sr) { nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start, segbuf->sb_sum.seg_seq, nilfs->ns_cno++); sbi->s_super->s_dirt = 1; clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); clear_bit(NILFS_SC_DIRTY, &sci->sc_flags); set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); } else clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); } static int nilfs_segctor_check_in_files(struct nilfs_sc_info *sci, struct nilfs_sb_info *sbi) { struct nilfs_inode_info *ii, *n; __u64 cno = sbi->s_nilfs->ns_cno; spin_lock(&sbi->s_inode_lock); retry: list_for_each_entry_safe(ii, n, &sbi->s_dirty_files, i_dirty) { if (!ii->i_bh) { struct buffer_head *ibh; int err; spin_unlock(&sbi->s_inode_lock); err = nilfs_ifile_get_inode_block( sbi->s_ifile, ii->vfs_inode.i_ino, &ibh); if (unlikely(err)) { nilfs_warning(sbi->s_super, __func__, "failed to get inode block.\n"); return err; } nilfs_mdt_mark_buffer_dirty(ibh); nilfs_mdt_mark_dirty(sbi->s_ifile); spin_lock(&sbi->s_inode_lock); if (likely(!ii->i_bh)) ii->i_bh = ibh; else brelse(ibh); goto retry; } ii->i_cno = cno; clear_bit(NILFS_I_QUEUED, &ii->i_state); set_bit(NILFS_I_BUSY, &ii->i_state); list_del(&ii->i_dirty); list_add_tail(&ii->i_dirty, &sci->sc_dirty_files); } spin_unlock(&sbi->s_inode_lock); NILFS_I(sbi->s_ifile)->i_cno = cno; return 0; } static void nilfs_segctor_check_out_files(struct nilfs_sc_info *sci, struct nilfs_sb_info *sbi) { struct nilfs_transaction_info *ti = current->journal_info; struct nilfs_inode_info *ii, *n; __u64 cno = sbi->s_nilfs->ns_cno; spin_lock(&sbi->s_inode_lock); list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) { if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) || test_bit(NILFS_I_DIRTY, &ii->i_state)) { /* The current checkpoint number (=nilfs->ns_cno) is changed between check-in and check-out only if the super root is written out. So, we can update i_cno for the inodes that remain in the dirty list. */ ii->i_cno = cno; continue; } clear_bit(NILFS_I_BUSY, &ii->i_state); brelse(ii->i_bh); ii->i_bh = NULL; list_del(&ii->i_dirty); list_add_tail(&ii->i_dirty, &ti->ti_garbage); } spin_unlock(&sbi->s_inode_lock); } /* * Main procedure of segment constructor */ static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) { struct nilfs_sb_info *sbi = sci->sc_sbi; struct the_nilfs *nilfs = sbi->s_nilfs; struct page *failed_page; int err, has_sr = 0; sci->sc_stage.scnt = NILFS_ST_INIT; err = nilfs_segctor_check_in_files(sci, sbi); if (unlikely(err)) goto out; if (nilfs_test_metadata_dirty(sbi)) set_bit(NILFS_SC_DIRTY, &sci->sc_flags); if (nilfs_segctor_clean(sci)) goto out; do { sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK; err = nilfs_segctor_begin_construction(sci, nilfs); if (unlikely(err)) goto out; /* Update time stamp */ sci->sc_seg_ctime = get_seconds(); err = nilfs_segctor_collect(sci, nilfs, mode); if (unlikely(err)) goto failed; has_sr = (sci->sc_super_root != NULL); /* Avoid empty segment */ if (sci->sc_stage.scnt == NILFS_ST_DONE && NILFS_SEG_EMPTY(&sci->sc_curseg->sb_sum)) { nilfs_segctor_end_construction(sci, nilfs, 1); goto out; } err = nilfs_segctor_assign(sci, mode); if (unlikely(err)) goto failed; if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) nilfs_segctor_fill_in_file_bmap(sci, sbi->s_ifile); if (has_sr) { err = nilfs_segctor_fill_in_checkpoint(sci); if (unlikely(err)) goto failed_to_make_up; nilfs_segctor_fill_in_super_root(sci, nilfs); } nilfs_segctor_update_segusage(sci, nilfs->ns_sufile); /* Write partial segments */ err = nilfs_segctor_prepare_write(sci, &failed_page); if (unlikely(err)) goto failed_to_write; nilfs_segctor_fill_in_checksums(sci, nilfs->ns_crc_seed); err = nilfs_segctor_write(sci, nilfs->ns_bdi); if (unlikely(err)) goto failed_to_write; nilfs_segctor_complete_write(sci); /* Commit segments */ if (has_sr) { nilfs_segctor_commit_free_segments(sci); nilfs_segctor_clear_metadata_dirty(sci); } nilfs_segctor_end_construction(sci, nilfs, 0); } while (sci->sc_stage.scnt != NILFS_ST_DONE); out: nilfs_segctor_destroy_segment_buffers(sci); nilfs_segctor_check_out_files(sci, sbi); return err; failed_to_write: nilfs_segctor_abort_write(sci, failed_page, err); nilfs_segctor_cancel_segusage(sci, nilfs->ns_sufile); failed_to_make_up: if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) nilfs_redirty_inodes(&sci->sc_dirty_files); failed: if (nilfs_doing_gc()) nilfs_redirty_inodes(&sci->sc_gc_inodes); nilfs_segctor_end_construction(sci, nilfs, err); goto out; } /** * nilfs_secgtor_start_timer - set timer of background write * @sci: nilfs_sc_info * * If the timer has already been set, it ignores the new request. * This function MUST be called within a section locking the segment * semaphore. */ static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) { spin_lock(&sci->sc_state_lock); if (sci->sc_timer && !(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { sci->sc_timer->expires = jiffies + sci->sc_interval; add_timer(sci->sc_timer); sci->sc_state |= NILFS_SEGCTOR_COMMIT; } spin_unlock(&sci->sc_state_lock); } static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn) { spin_lock(&sci->sc_state_lock); if (!(sci->sc_flush_request & (1 << bn))) { unsigned long prev_req = sci->sc_flush_request; sci->sc_flush_request |= (1 << bn); if (!prev_req) wake_up(&sci->sc_wait_daemon); } spin_unlock(&sci->sc_state_lock); } /** * nilfs_flush_segment - trigger a segment construction for resource control * @sb: super block * @ino: inode number of the file to be flushed out. */ void nilfs_flush_segment(struct super_block *sb, ino_t ino) { struct nilfs_sb_info *sbi = NILFS_SB(sb); struct nilfs_sc_info *sci = NILFS_SC(sbi); if (!sci || nilfs_doing_construction()) return; nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0); /* assign bit 0 to data files */ } int nilfs_segctor_add_segments_to_be_freed(struct nilfs_sc_info *sci, __u64 *segnum, size_t nsegs) { struct nilfs_segment_entry *ent; struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs; struct inode *sufile = nilfs->ns_sufile; LIST_HEAD(list); __u64 *pnum; size_t i; int err; for (pnum = segnum, i = 0; i < nsegs; pnum++, i++) { ent = nilfs_alloc_segment_entry(*pnum); if (unlikely(!ent)) { err = -ENOMEM; goto failed; } list_add_tail(&ent->list, &list); err = nilfs_open_segment_entry(ent, sufile); if (unlikely(err)) goto failed; if (unlikely(!nilfs_segment_usage_dirty(ent->raw_su))) printk(KERN_WARNING "NILFS: unused segment is " "requested to be cleaned (segnum=%llu)\n", (unsigned long long)ent->segnum); nilfs_close_segment_entry(ent, sufile); } list_splice(&list, sci->sc_cleaning_segments.prev); return 0; failed: nilfs_dispose_segment_list(&list); return err; } void nilfs_segctor_clear_segments_to_be_freed(struct nilfs_sc_info *sci) { nilfs_dispose_segment_list(&sci->sc_cleaning_segments); } struct nilfs_segctor_wait_request { wait_queue_t wq; __u32 seq; int err; atomic_t done; }; static int nilfs_segctor_sync(struct nilfs_sc_info *sci) { struct nilfs_segctor_wait_request wait_req; int err = 0; spin_lock(&sci->sc_state_lock); init_wait(&wait_req.wq); wait_req.err = 0; atomic_set(&wait_req.done, 0); wait_req.seq = ++sci->sc_seq_request; spin_unlock(&sci->sc_state_lock); init_waitqueue_entry(&wait_req.wq, current); add_wait_queue(&sci->sc_wait_request, &wait_req.wq); set_current_state(TASK_INTERRUPTIBLE); wake_up(&sci->sc_wait_daemon); for (;;) { if (atomic_read(&wait_req.done)) { err = wait_req.err; break; } if (!signal_pending(current)) { schedule(); continue; } err = -ERESTARTSYS; break; } finish_wait(&sci->sc_wait_request, &wait_req.wq); return err; } static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err) { struct nilfs_segctor_wait_request *wrq, *n; unsigned long flags; spin_lock_irqsave(&sci->sc_wait_request.lock, flags); list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list, wq.task_list) { if (!atomic_read(&wrq->done) && nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) { wrq->err = err; atomic_set(&wrq->done, 1); } if (atomic_read(&wrq->done)) { wrq->wq.func(&wrq->wq, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 0, NULL); } } spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags); } /** * nilfs_construct_segment - construct a logical segment * @sb: super block * * Return Value: On success, 0 is retured. On errors, one of the following * negative error code is returned. * * %-EROFS - Read only filesystem. * * %-EIO - I/O error * * %-ENOSPC - No space left on device (only in a panic state). * * %-ERESTARTSYS - Interrupted. * * %-ENOMEM - Insufficient memory available. */ int nilfs_construct_segment(struct super_block *sb) { struct nilfs_sb_info *sbi = NILFS_SB(sb); struct nilfs_sc_info *sci = NILFS_SC(sbi); struct nilfs_transaction_info *ti; int err; if (!sci) return -EROFS; /* A call inside transactions causes a deadlock. */ BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC); err = nilfs_segctor_sync(sci); return err; } /** * nilfs_construct_dsync_segment - construct a data-only logical segment * @sb: super block * @inode: inode whose data blocks should be written out * @start: start byte offset * @end: end byte offset (inclusive) * * Return Value: On success, 0 is retured. On errors, one of the following * negative error code is returned. * * %-EROFS - Read only filesystem. * * %-EIO - I/O error * * %-ENOSPC - No space left on device (only in a panic state). * * %-ERESTARTSYS - Interrupted. * * %-ENOMEM - Insufficient memory available. */ int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode, loff_t start, loff_t end) { struct nilfs_sb_info *sbi = NILFS_SB(sb); struct nilfs_sc_info *sci = NILFS_SC(sbi); struct nilfs_inode_info *ii; struct nilfs_transaction_info ti; int err = 0; if (!sci) return -EROFS; nilfs_transaction_lock(sbi, &ti, 0); ii = NILFS_I(inode); if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) || nilfs_test_opt(sbi, STRICT_ORDER) || test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || nilfs_discontinued(sbi->s_nilfs)) { nilfs_transaction_unlock(sbi); err = nilfs_segctor_sync(sci); return err; } spin_lock(&sbi->s_inode_lock); if (!test_bit(NILFS_I_QUEUED, &ii->i_state) && !test_bit(NILFS_I_BUSY, &ii->i_state)) { spin_unlock(&sbi->s_inode_lock); nilfs_transaction_unlock(sbi); return 0; } spin_unlock(&sbi->s_inode_lock); sci->sc_dsync_inode = ii; sci->sc_dsync_start = start; sci->sc_dsync_end = end; err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC); nilfs_transaction_unlock(sbi); return err; } struct nilfs_segctor_req { int mode; __u32 seq_accepted; int sc_err; /* construction failure */ int sb_err; /* super block writeback failure */ }; #define FLUSH_FILE_BIT (0x1) /* data file only */ #define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */ static void nilfs_segctor_accept(struct nilfs_sc_info *sci, struct nilfs_segctor_req *req) { req->sc_err = req->sb_err = 0; spin_lock(&sci->sc_state_lock); req->seq_accepted = sci->sc_seq_request; spin_unlock(&sci->sc_state_lock); if (sci->sc_timer) del_timer_sync(sci->sc_timer); } static void nilfs_segctor_notify(struct nilfs_sc_info *sci, struct nilfs_segctor_req *req) { /* Clear requests (even when the construction failed) */ spin_lock(&sci->sc_state_lock); sci->sc_state &= ~NILFS_SEGCTOR_COMMIT; if (req->mode == SC_LSEG_SR) { sci->sc_seq_done = req->seq_accepted; nilfs_segctor_wakeup(sci, req->sc_err ? : req->sb_err); sci->sc_flush_request = 0; } else if (req->mode == SC_FLUSH_FILE) sci->sc_flush_request &= ~FLUSH_FILE_BIT; else if (req->mode == SC_FLUSH_DAT) sci->sc_flush_request &= ~FLUSH_DAT_BIT; spin_unlock(&sci->sc_state_lock); } static int nilfs_segctor_construct(struct nilfs_sc_info *sci, struct nilfs_segctor_req *req) { struct nilfs_sb_info *sbi = sci->sc_sbi; struct the_nilfs *nilfs = sbi->s_nilfs; int err = 0; if (nilfs_discontinued(nilfs)) req->mode = SC_LSEG_SR; if (!nilfs_segctor_confirm(sci)) { err = nilfs_segctor_do_construct(sci, req->mode); req->sc_err = err; } if (likely(!err)) { if (req->mode != SC_FLUSH_DAT) atomic_set(&nilfs->ns_ndirtyblks, 0); if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) && nilfs_discontinued(nilfs)) { down_write(&nilfs->ns_sem); req->sb_err = nilfs_commit_super(sbi, 0); up_write(&nilfs->ns_sem); } } return err; } static void nilfs_construction_timeout(unsigned long data) { struct task_struct *p = (struct task_struct *)data; wake_up_process(p); } static void nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head) { struct nilfs_inode_info *ii, *n; list_for_each_entry_safe(ii, n, head, i_dirty) { if (!test_bit(NILFS_I_UPDATED, &ii->i_state)) continue; hlist_del_init(&ii->vfs_inode.i_hash); list_del_init(&ii->i_dirty); nilfs_clear_gcinode(&ii->vfs_inode); } } int nilfs_clean_segments(struct super_block *sb, void __user *argp) { struct nilfs_sb_info *sbi = NILFS_SB(sb); struct nilfs_sc_info *sci = NILFS_SC(sbi); struct the_nilfs *nilfs = sbi->s_nilfs; struct nilfs_transaction_info ti; struct nilfs_segctor_req req = { .mode = SC_LSEG_SR }; int err; if (unlikely(!sci)) return -EROFS; nilfs_transaction_lock(sbi, &ti, 1); err = nilfs_init_gcdat_inode(nilfs); if (unlikely(err)) goto out_unlock; err = nilfs_ioctl_prepare_clean_segments(nilfs, argp); if (unlikely(err)) goto out_unlock; list_splice_init(&nilfs->ns_gc_inodes, sci->sc_gc_inodes.prev); for (;;) { nilfs_segctor_accept(sci, &req); err = nilfs_segctor_construct(sci, &req); nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes); nilfs_segctor_notify(sci, &req); if (likely(!err)) break; nilfs_warning(sb, __func__, "segment construction failed. (err=%d)", err); set_current_state(TASK_INTERRUPTIBLE); schedule_timeout(sci->sc_interval); } out_unlock: nilfs_clear_gcdat_inode(nilfs); nilfs_transaction_unlock(sbi); return err; } static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode) { struct nilfs_sb_info *sbi = sci->sc_sbi; struct nilfs_transaction_info ti; struct nilfs_segctor_req req = { .mode = mode }; nilfs_transaction_lock(sbi, &ti, 0); nilfs_segctor_accept(sci, &req); nilfs_segctor_construct(sci, &req); nilfs_segctor_notify(sci, &req); /* * Unclosed segment should be retried. We do this using sc_timer. * Timeout of sc_timer will invoke complete construction which leads * to close the current logical segment. */ if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) nilfs_segctor_start_timer(sci); nilfs_transaction_unlock(sbi); } static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci) { int mode = 0; int err; spin_lock(&sci->sc_state_lock); mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ? SC_FLUSH_DAT : SC_FLUSH_FILE; spin_unlock(&sci->sc_state_lock); if (mode) { err = nilfs_segctor_do_construct(sci, mode); spin_lock(&sci->sc_state_lock); sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ? ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT; spin_unlock(&sci->sc_state_lock); } clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); } static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci) { if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) { if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT)) return SC_FLUSH_FILE; else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT)) return SC_FLUSH_DAT; } return SC_LSEG_SR; } /** * nilfs_segctor_thread - main loop of the segment constructor thread. * @arg: pointer to a struct nilfs_sc_info. * * nilfs_segctor_thread() initializes a timer and serves as a daemon * to execute segment constructions. */ static int nilfs_segctor_thread(void *arg) { struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; struct timer_list timer; int timeout = 0; init_timer(&timer); timer.data = (unsigned long)current; timer.function = nilfs_construction_timeout; sci->sc_timer = &timer; /* start sync. */ sci->sc_task = current; wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */ printk(KERN_INFO "segctord starting. Construction interval = %lu seconds, " "CP frequency < %lu seconds\n", sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ); spin_lock(&sci->sc_state_lock); loop: for (;;) { int mode; if (sci->sc_state & NILFS_SEGCTOR_QUIT) goto end_thread; if (timeout || sci->sc_seq_request != sci->sc_seq_done) mode = SC_LSEG_SR; else if (!sci->sc_flush_request) break; else mode = nilfs_segctor_flush_mode(sci); spin_unlock(&sci->sc_state_lock); nilfs_segctor_thread_construct(sci, mode); spin_lock(&sci->sc_state_lock); timeout = 0; } if (freezing(current)) { spin_unlock(&sci->sc_state_lock); refrigerator(); spin_lock(&sci->sc_state_lock); } else { DEFINE_WAIT(wait); int should_sleep = 1; prepare_to_wait(&sci->sc_wait_daemon, &wait, TASK_INTERRUPTIBLE); if (sci->sc_seq_request != sci->sc_seq_done) should_sleep = 0; else if (sci->sc_flush_request) should_sleep = 0; else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) should_sleep = time_before(jiffies, sci->sc_timer->expires); if (should_sleep) { spin_unlock(&sci->sc_state_lock); schedule(); spin_lock(&sci->sc_state_lock); } finish_wait(&sci->sc_wait_daemon, &wait); timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && time_after_eq(jiffies, sci->sc_timer->expires)); } goto loop; end_thread: spin_unlock(&sci->sc_state_lock); del_timer_sync(sci->sc_timer); sci->sc_timer = NULL; /* end sync. */ sci->sc_task = NULL; wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */ return 0; } static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci) { struct task_struct *t; t = kthread_run(nilfs_segctor_thread, sci, "segctord"); if (IS_ERR(t)) { int err = PTR_ERR(t); printk(KERN_ERR "NILFS: error %d creating segctord thread\n", err); return err; } wait_event(sci->sc_wait_task, sci->sc_task != NULL); return 0; } static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci) { sci->sc_state |= NILFS_SEGCTOR_QUIT; while (sci->sc_task) { wake_up(&sci->sc_wait_daemon); spin_unlock(&sci->sc_state_lock); wait_event(sci->sc_wait_task, sci->sc_task == NULL); spin_lock(&sci->sc_state_lock); } } static int nilfs_segctor_init(struct nilfs_sc_info *sci) { sci->sc_seq_done = sci->sc_seq_request; return nilfs_segctor_start_thread(sci); } /* * Setup & clean-up functions */ static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi) { struct nilfs_sc_info *sci; sci = kzalloc(sizeof(*sci), GFP_KERNEL); if (!sci) return NULL; sci->sc_sbi = sbi; sci->sc_super = sbi->s_super; init_waitqueue_head(&sci->sc_wait_request); init_waitqueue_head(&sci->sc_wait_daemon); init_waitqueue_head(&sci->sc_wait_task); spin_lock_init(&sci->sc_state_lock); INIT_LIST_HEAD(&sci->sc_dirty_files); INIT_LIST_HEAD(&sci->sc_segbufs); INIT_LIST_HEAD(&sci->sc_gc_inodes); INIT_LIST_HEAD(&sci->sc_cleaning_segments); INIT_LIST_HEAD(&sci->sc_copied_buffers); sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK; if (sbi->s_interval) sci->sc_interval = sbi->s_interval; if (sbi->s_watermark) sci->sc_watermark = sbi->s_watermark; return sci; } static void nilfs_segctor_write_out(struct nilfs_sc_info *sci) { int ret, retrycount = NILFS_SC_CLEANUP_RETRY; /* The segctord thread was stopped and its timer was removed. But some tasks remain. */ do { struct nilfs_sb_info *sbi = sci->sc_sbi; struct nilfs_transaction_info ti; struct nilfs_segctor_req req = { .mode = SC_LSEG_SR }; nilfs_transaction_lock(sbi, &ti, 0); nilfs_segctor_accept(sci, &req); ret = nilfs_segctor_construct(sci, &req); nilfs_segctor_notify(sci, &req); nilfs_transaction_unlock(sbi); } while (ret && retrycount-- > 0); } /** * nilfs_segctor_destroy - destroy the segment constructor. * @sci: nilfs_sc_info * * nilfs_segctor_destroy() kills the segctord thread and frees * the nilfs_sc_info struct. * Caller must hold the segment semaphore. */ static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) { struct nilfs_sb_info *sbi = sci->sc_sbi; int flag; up_write(&sbi->s_nilfs->ns_segctor_sem); spin_lock(&sci->sc_state_lock); nilfs_segctor_kill_thread(sci); flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request || sci->sc_seq_request != sci->sc_seq_done); spin_unlock(&sci->sc_state_lock); if (flag || nilfs_segctor_confirm(sci)) nilfs_segctor_write_out(sci); WARN_ON(!list_empty(&sci->sc_copied_buffers)); if (!list_empty(&sci->sc_dirty_files)) { nilfs_warning(sbi->s_super, __func__, "dirty file(s) after the final construction\n"); nilfs_dispose_list(sbi, &sci->sc_dirty_files, 1); } if (!list_empty(&sci->sc_cleaning_segments)) nilfs_dispose_segment_list(&sci->sc_cleaning_segments); WARN_ON(!list_empty(&sci->sc_segbufs)); down_write(&sbi->s_nilfs->ns_segctor_sem); kfree(sci); } /** * nilfs_attach_segment_constructor - attach a segment constructor * @sbi: nilfs_sb_info * * nilfs_attach_segment_constructor() allocates a struct nilfs_sc_info, * initilizes it, and starts the segment constructor. * * Return Value: On success, 0 is returned. On error, one of the following * negative error code is returned. * * %-ENOMEM - Insufficient memory available. */ int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi) { struct the_nilfs *nilfs = sbi->s_nilfs; int err; /* Each field of nilfs_segctor is cleared through the initialization of super-block info */ sbi->s_sc_info = nilfs_segctor_new(sbi); if (!sbi->s_sc_info) return -ENOMEM; nilfs_attach_writer(nilfs, sbi); err = nilfs_segctor_init(NILFS_SC(sbi)); if (err) { nilfs_detach_writer(nilfs, sbi); kfree(sbi->s_sc_info); sbi->s_sc_info = NULL; } return err; } /** * nilfs_detach_segment_constructor - destroy the segment constructor * @sbi: nilfs_sb_info * * nilfs_detach_segment_constructor() kills the segment constructor daemon, * frees the struct nilfs_sc_info, and destroy the dirty file list. */ void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi) { struct the_nilfs *nilfs = sbi->s_nilfs; LIST_HEAD(garbage_list); down_write(&nilfs->ns_segctor_sem); if (NILFS_SC(sbi)) { nilfs_segctor_destroy(NILFS_SC(sbi)); sbi->s_sc_info = NULL; } /* Force to free the list of dirty files */ spin_lock(&sbi->s_inode_lock); if (!list_empty(&sbi->s_dirty_files)) { list_splice_init(&sbi->s_dirty_files, &garbage_list); nilfs_warning(sbi->s_super, __func__, "Non empty dirty list after the last " "segment construction\n"); } spin_unlock(&sbi->s_inode_lock); up_write(&nilfs->ns_segctor_sem); nilfs_dispose_list(sbi, &garbage_list, 1); nilfs_detach_writer(nilfs, sbi); }