From 890871be854b5f5e43e7ba2475f706209906cc24 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Wed, 2 Sep 2009 16:24:52 -0400 Subject: Btrfs: switch extent_map to a rw lock There are two main users of the extent_map tree. The first is regular file inodes, where it is evenly spread between readers and writers. The second is the chunk allocation tree, which maps blocks from logical addresses to phyiscal ones, and it is 99.99% reads. The mapping tree is a point of lock contention during heavy IO workloads, so this commit switches things to a rw lock. Signed-off-by: Chris Mason --- fs/btrfs/inode.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 04b53b5ebe5..f1df1171861 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -612,9 +612,9 @@ static noinline int submit_compressed_extents(struct inode *inode, set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); while (1) { - spin_lock(&em_tree->lock); + write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); - spin_unlock(&em_tree->lock); + write_unlock(&em_tree->lock); if (ret != -EEXIST) { free_extent_map(em); break; @@ -748,9 +748,9 @@ static noinline int cow_file_range(struct inode *inode, set_bit(EXTENT_FLAG_PINNED, &em->flags); while (1) { - spin_lock(&em_tree->lock); + write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); - spin_unlock(&em_tree->lock); + write_unlock(&em_tree->lock); if (ret != -EEXIST) { free_extent_map(em); break; @@ -1081,9 +1081,9 @@ out_check: em->bdev = root->fs_info->fs_devices->latest_bdev; set_bit(EXTENT_FLAG_PINNED, &em->flags); while (1) { - spin_lock(&em_tree->lock); + write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); - spin_unlock(&em_tree->lock); + write_unlock(&em_tree->lock); if (ret != -EEXIST) { free_extent_map(em); break; @@ -1670,13 +1670,13 @@ static int btrfs_io_failed_hook(struct bio *failed_bio, failrec->last_mirror = 0; failrec->bio_flags = 0; - spin_lock(&em_tree->lock); + read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, start, failrec->len); if (em->start > start || em->start + em->len < start) { free_extent_map(em); em = NULL; } - spin_unlock(&em_tree->lock); + read_unlock(&em_tree->lock); if (!em || IS_ERR(em)) { kfree(failrec); @@ -4069,11 +4069,11 @@ struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, int compressed; again: - spin_lock(&em_tree->lock); + read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, start, len); if (em) em->bdev = root->fs_info->fs_devices->latest_bdev; - spin_unlock(&em_tree->lock); + read_unlock(&em_tree->lock); if (em) { if (em->start > start || em->start + em->len <= start) @@ -4264,7 +4264,7 @@ insert: } err = 0; - spin_lock(&em_tree->lock); + write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); /* it is possible that someone inserted the extent into the tree * while we had the lock dropped. It is also possible that @@ -4304,7 +4304,7 @@ insert: err = 0; } } - spin_unlock(&em_tree->lock); + write_unlock(&em_tree->lock); out: if (path) btrfs_free_path(path); -- cgit v1.2.3-70-g09d2 From 2c64c53d8d30d43d0670482503a3914dfd3d6d46 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Wed, 2 Sep 2009 15:04:12 -0400 Subject: Btrfs: cache values for locking extents Many of the btrfs extent state tree users follow the same pattern. They lock an extent range in the tree, do some operation and then unlock. This translates to at least 2 rbtree searches, and maybe more if they are doing operations on the extent state tree. A locked extent in the tree isn't going to be merged or changed, and so we can safely return the extent state structure as a cached handle. This changes set_extent_bit to give back a cached handle, and also changes both set_extent_bit and clear_extent_bit to use the cached handle if it is available. Signed-off-by: Chris Mason --- fs/btrfs/extent_io.c | 125 ++++++++++++++++++++++++++++++++++++++------------- fs/btrfs/extent_io.h | 5 ++- fs/btrfs/inode.c | 6 +-- 3 files changed, 100 insertions(+), 36 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 7c70613eb72..c7a5e860fe2 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -471,10 +471,14 @@ static int clear_state_bit(struct extent_io_tree *tree, * bits were already set, or zero if none of the bits were already set. */ int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, - int bits, int wake, int delete, gfp_t mask) + int bits, int wake, int delete, + struct extent_state **cached_state, + gfp_t mask) { struct extent_state *state; + struct extent_state *cached; struct extent_state *prealloc = NULL; + struct rb_node *next_node; struct rb_node *node; u64 last_end; int err; @@ -488,6 +492,17 @@ again: } spin_lock(&tree->lock); + if (cached_state) { + cached = *cached_state; + *cached_state = NULL; + if (cached->tree && cached->start == start) { + atomic_dec(&cached->refs); + state = cached; + last_end = state->end; + goto found; + } + free_extent_state(cached); + } /* * this search will find the extents that end after * our range starts @@ -496,6 +511,7 @@ again: if (!node) goto out; state = rb_entry(node, struct extent_state, rb_node); +hit_next: if (state->start > end) goto out; WARN_ON(state->end < start); @@ -555,11 +571,21 @@ again: prealloc = NULL; goto out; } - +found: + if (state->end < end && prealloc && !need_resched()) + next_node = rb_next(&state->rb_node); + else + next_node = NULL; set |= clear_state_bit(tree, state, bits, wake, delete); if (last_end == (u64)-1) goto out; start = last_end + 1; + if (start <= end && next_node) { + state = rb_entry(next_node, struct extent_state, + rb_node); + if (state->start == start) + goto hit_next; + } goto search_again; out: @@ -653,6 +679,17 @@ static void set_state_bits(struct extent_io_tree *tree, state->state |= bits; } +static void cache_state(struct extent_state *state, + struct extent_state **cached_ptr) +{ + if (cached_ptr && !(*cached_ptr)) { + if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) { + *cached_ptr = state; + atomic_inc(&state->refs); + } + } +} + /* * set some bits on a range in the tree. This may require allocations or * sleeping, so the gfp mask is used to indicate what is allowed. @@ -666,6 +703,7 @@ static void set_state_bits(struct extent_io_tree *tree, static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits, int exclusive_bits, u64 *failed_start, + struct extent_state **cached_state, gfp_t mask) { struct extent_state *state; @@ -712,6 +750,7 @@ hit_next: goto out; } set_state_bits(tree, state, bits); + cache_state(state, cached_state); merge_state(tree, state); if (last_end == (u64)-1) goto out; @@ -758,6 +797,7 @@ hit_next: goto out; if (state->end <= end) { set_state_bits(tree, state, bits); + cache_state(state, cached_state); merge_state(tree, state); if (last_end == (u64)-1) goto out; @@ -782,6 +822,7 @@ hit_next: this_end = last_start - 1; err = insert_state(tree, prealloc, start, this_end, bits); + cache_state(prealloc, cached_state); prealloc = NULL; BUG_ON(err == -EEXIST); if (err) @@ -805,6 +846,7 @@ hit_next: BUG_ON(err == -EEXIST); set_state_bits(tree, prealloc, bits); + cache_state(prealloc, cached_state); merge_state(tree, prealloc); prealloc = NULL; goto out; @@ -833,26 +875,27 @@ int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, - mask); + NULL, mask); } int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { - return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, mask); + return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, NULL, + mask); } int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits, gfp_t mask) { return set_extent_bit(tree, start, end, bits, 0, NULL, - mask); + NULL, mask); } int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits, gfp_t mask) { - return clear_extent_bit(tree, start, end, bits, 0, 0, mask); + return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask); } int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, @@ -860,46 +903,50 @@ int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, { return set_extent_bit(tree, start, end, EXTENT_DELALLOC | EXTENT_DIRTY | EXTENT_UPTODATE, - 0, NULL, mask); + 0, NULL, NULL, mask); } int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { return clear_extent_bit(tree, start, end, - EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); + EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, + NULL, mask); } int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { - return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, mask); + return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, + NULL, mask); } int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, - mask); + NULL, mask); } static int clear_extent_new(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { - return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); + return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, + NULL, mask); } int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, - mask); + NULL, mask); } static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { - return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); + return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, + NULL, mask); } int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end) @@ -912,13 +959,14 @@ int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end) * us if waiting is desired. */ int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, - int bits, gfp_t mask) + int bits, struct extent_state **cached_state, gfp_t mask) { int err; u64 failed_start; while (1) { err = set_extent_bit(tree, start, end, EXTENT_LOCKED | bits, - EXTENT_LOCKED, &failed_start, mask); + EXTENT_LOCKED, &failed_start, + cached_state, mask); if (err == -EEXIST && (mask & __GFP_WAIT)) { wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); start = failed_start; @@ -932,7 +980,7 @@ int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { - return lock_extent_bits(tree, start, end, 0, mask); + return lock_extent_bits(tree, start, end, 0, NULL, mask); } int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, @@ -941,21 +989,29 @@ int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, int err; u64 failed_start; - err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, - &failed_start, mask); + err = set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED, + &failed_start, NULL, mask); if (err == -EEXIST) { if (failed_start > start) clear_extent_bit(tree, start, failed_start - 1, - EXTENT_LOCKED, 1, 0, mask); + EXTENT_LOCKED, 1, 0, NULL, mask); return 0; } return 1; } +int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end, + struct extent_state **cached, gfp_t mask) +{ + return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached, + mask); +} + int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { - return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); + return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL, + mask); } /* @@ -1323,7 +1379,7 @@ int extent_clear_unlock_delalloc(struct inode *inode, if (clear_delalloc) clear_bits |= EXTENT_DELALLOC; - clear_extent_bit(tree, start, end, clear_bits, 1, 0, GFP_NOFS); + clear_extent_bit(tree, start, end, clear_bits, 1, 0, NULL, GFP_NOFS); if (!(unlock_pages || clear_dirty || set_writeback || end_writeback)) return 0; @@ -2071,6 +2127,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, u64 iosize; u64 unlock_start; sector_t sector; + struct extent_state *cached_state = NULL; struct extent_map *em; struct block_device *bdev; int ret; @@ -2162,7 +2219,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, goto done_unlocked; } } - lock_extent(tree, start, page_end, GFP_NOFS); + lock_extent_bits(tree, start, page_end, 0, &cached_state, GFP_NOFS); unlock_start = start; @@ -2170,7 +2227,8 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, ret = tree->ops->writepage_start_hook(page, start, page_end); if (ret == -EAGAIN) { - unlock_extent(tree, start, page_end, GFP_NOFS); + unlock_extent_cached(tree, start, page_end, + &cached_state, GFP_NOFS); redirty_page_for_writepage(wbc, page); update_nr_written(page, wbc, nr_written); unlock_page(page); @@ -2192,7 +2250,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, if (last_byte <= start) { clear_extent_bit(tree, start, page_end, EXTENT_LOCKED | EXTENT_DIRTY, - 1, 0, GFP_NOFS); + 1, 0, NULL, GFP_NOFS); if (tree->ops && tree->ops->writepage_end_io_hook) tree->ops->writepage_end_io_hook(page, start, page_end, NULL, 1); @@ -2204,7 +2262,8 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, while (cur <= end) { if (cur >= last_byte) { - unlock_extent(tree, unlock_start, page_end, GFP_NOFS); + unlock_extent_cached(tree, unlock_start, page_end, + &cached_state, GFP_NOFS); if (tree->ops && tree->ops->writepage_end_io_hook) tree->ops->writepage_end_io_hook(page, cur, page_end, NULL, 1); @@ -2236,8 +2295,9 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, */ if (compressed || block_start == EXTENT_MAP_HOLE || block_start == EXTENT_MAP_INLINE) { - unlock_extent(tree, unlock_start, cur + iosize - 1, - GFP_NOFS); + unlock_extent_cached(tree, unlock_start, + cur + iosize - 1, &cached_state, + GFP_NOFS); /* * end_io notification does not happen here for @@ -2307,11 +2367,14 @@ done: end_page_writeback(page); } if (unlock_start <= page_end) - unlock_extent(tree, unlock_start, page_end, GFP_NOFS); + unlock_extent_cached(tree, unlock_start, page_end, + &cached_state, GFP_NOFS); unlock_page(page); done_unlocked: + /* drop our reference on any cached states */ + free_extent_state(cached_state); return 0; } @@ -2599,7 +2662,7 @@ int extent_invalidatepage(struct extent_io_tree *tree, wait_on_page_writeback(page); clear_extent_bit(tree, start, end, EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, - 1, 1, GFP_NOFS); + 1, 1, NULL, GFP_NOFS); return 0; } @@ -2693,7 +2756,7 @@ int extent_prepare_write(struct extent_io_tree *tree, */ set_extent_bit(tree, block_start, block_start + iosize - 1, - EXTENT_LOCKED, 0, NULL, GFP_NOFS); + EXTENT_LOCKED, 0, NULL, NULL, GFP_NOFS); ret = submit_extent_page(READ, tree, page, sector, iosize, page_offset, em->bdev, NULL, 1, @@ -2740,7 +2803,7 @@ int try_release_extent_state(struct extent_map_tree *map, if ((mask & GFP_NOFS) == GFP_NOFS) mask = GFP_NOFS; clear_extent_bit(tree, start, end, EXTENT_UPTODATE, - 1, 1, mask); + 1, 1, NULL, mask); } return ret; } diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 88d134d01fb..c8ead2b8c4c 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -143,7 +143,7 @@ int try_release_extent_state(struct extent_map_tree *map, gfp_t mask); int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask); int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, - int bits, gfp_t mask); + int bits, struct extent_state **cached, gfp_t mask); int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask); int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask); @@ -161,7 +161,8 @@ int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits, gfp_t mask); int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, - int bits, int wake, int delete, gfp_t mask); + int bits, int wake, int delete, struct extent_state **cached, + gfp_t mask); int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits, gfp_t mask); int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index f1df1171861..e494545c420 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -854,7 +854,7 @@ static int cow_file_range_async(struct inode *inode, struct page *locked_page, int limit = 10 * 1024 * 1042; clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED | - EXTENT_DELALLOC, 1, 0, GFP_NOFS); + EXTENT_DELALLOC, 1, 0, NULL, GFP_NOFS); while (start < end) { async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS); async_cow->inode = inode; @@ -4420,7 +4420,7 @@ static void btrfs_invalidatepage(struct page *page, unsigned long offset) */ clear_extent_bit(tree, page_start, page_end, EXTENT_DIRTY | EXTENT_DELALLOC | - EXTENT_LOCKED, 1, 0, GFP_NOFS); + EXTENT_LOCKED, 1, 0, NULL, GFP_NOFS); btrfs_finish_ordered_io(page->mapping->host, page_start, page_end); btrfs_put_ordered_extent(ordered); @@ -4429,7 +4429,7 @@ static void btrfs_invalidatepage(struct page *page, unsigned long offset) clear_extent_bit(tree, page_start, page_end, EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_ORDERED, - 1, 1, GFP_NOFS); + 1, 1, NULL, GFP_NOFS); __btrfs_releasepage(page, GFP_NOFS); ClearPageChecked(page); -- cgit v1.2.3-70-g09d2 From 9655d2982b53fdb38a9e0f2f11315b99b92d66e2 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Wed, 2 Sep 2009 15:22:30 -0400 Subject: Btrfs: use a cached state for extent state operations during delalloc This changes the btrfs code to find delalloc ranges in the extent state tree to use the new state caching code from set/test bit. It reduces one of the biggest causes of rbtree searches in the writeback path. test_range_bit is also modified to take the cached state as a starting point while searching. Signed-off-by: Chris Mason --- fs/btrfs/extent_io.c | 46 +++++++++++++++++++++++++++++++--------------- fs/btrfs/extent_io.h | 2 +- fs/btrfs/inode.c | 6 +++--- fs/btrfs/ordered-data.c | 8 ++++---- fs/btrfs/relocation.c | 2 +- 5 files changed, 40 insertions(+), 24 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 04fafc3cffc..c9a438d374b 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -720,6 +720,13 @@ again: } spin_lock(&tree->lock); + if (cached_state && *cached_state) { + state = *cached_state; + if (state->start == start && state->tree) { + node = &state->rb_node; + goto hit_next; + } + } /* * this search will find all the extents that end after * our range starts. @@ -1286,6 +1293,7 @@ static noinline u64 find_lock_delalloc_range(struct inode *inode, u64 delalloc_start; u64 delalloc_end; u64 found; + struct extent_state *cached_state = NULL; int ret; int loops = 0; @@ -1323,6 +1331,7 @@ again: /* some of the pages are gone, lets avoid looping by * shortening the size of the delalloc range we're searching */ + free_extent_state(cached_state); if (!loops) { unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1); max_bytes = PAGE_CACHE_SIZE - offset; @@ -1336,18 +1345,21 @@ again: BUG_ON(ret); /* step three, lock the state bits for the whole range */ - lock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); + lock_extent_bits(tree, delalloc_start, delalloc_end, + 0, &cached_state, GFP_NOFS); /* then test to make sure it is all still delalloc */ ret = test_range_bit(tree, delalloc_start, delalloc_end, - EXTENT_DELALLOC, 1); + EXTENT_DELALLOC, 1, cached_state); if (!ret) { - unlock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); + unlock_extent_cached(tree, delalloc_start, delalloc_end, + &cached_state, GFP_NOFS); __unlock_for_delalloc(inode, locked_page, delalloc_start, delalloc_end); cond_resched(); goto again; } + free_extent_state(cached_state); *start = delalloc_start; *end = delalloc_end; out_failed: @@ -1530,14 +1542,17 @@ out: * range is found set. */ int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, - int bits, int filled) + int bits, int filled, struct extent_state *cached) { struct extent_state *state = NULL; struct rb_node *node; int bitset = 0; spin_lock(&tree->lock); - node = tree_search(tree, start); + if (cached && cached->tree && cached->start == start) + node = &cached->rb_node; + else + node = tree_search(tree, start); while (node && start <= end) { state = rb_entry(node, struct extent_state, rb_node); @@ -1580,7 +1595,7 @@ static int check_page_uptodate(struct extent_io_tree *tree, { u64 start = (u64)page->index << PAGE_CACHE_SHIFT; u64 end = start + PAGE_CACHE_SIZE - 1; - if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) + if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL)) SetPageUptodate(page); return 0; } @@ -1594,7 +1609,7 @@ static int check_page_locked(struct extent_io_tree *tree, { u64 start = (u64)page->index << PAGE_CACHE_SHIFT; u64 end = start + PAGE_CACHE_SIZE - 1; - if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) + if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0, NULL)) unlock_page(page); return 0; } @@ -2032,7 +2047,8 @@ static int __extent_read_full_page(struct extent_io_tree *tree, continue; } /* the get_extent function already copied into the page */ - if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { + if (test_range_bit(tree, cur, cur_end, + EXTENT_UPTODATE, 1, NULL)) { check_page_uptodate(tree, page); unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); cur = cur + iosize; @@ -2305,7 +2321,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, } /* leave this out until we have a page_mkwrite call */ if (0 && !test_range_bit(tree, cur, cur + iosize - 1, - EXTENT_DIRTY, 0)) { + EXTENT_DIRTY, 0, NULL)) { cur = cur + iosize; pg_offset += iosize; continue; @@ -2721,7 +2737,7 @@ int extent_prepare_write(struct extent_io_tree *tree, !isnew && !PageUptodate(page) && (block_off_end > to || block_off_start < from) && !test_range_bit(tree, block_start, cur_end, - EXTENT_UPTODATE, 1)) { + EXTENT_UPTODATE, 1, NULL)) { u64 sector; u64 extent_offset = block_start - em->start; size_t iosize; @@ -2776,7 +2792,7 @@ int try_release_extent_state(struct extent_map_tree *map, int ret = 1; if (test_range_bit(tree, start, end, - EXTENT_IOBITS | EXTENT_ORDERED, 0)) + EXTENT_IOBITS | EXTENT_ORDERED, 0, NULL)) ret = 0; else { if ((mask & GFP_NOFS) == GFP_NOFS) @@ -2821,7 +2837,7 @@ int try_release_extent_mapping(struct extent_map_tree *map, extent_map_end(em) - 1, EXTENT_LOCKED | EXTENT_WRITEBACK | EXTENT_ORDERED, - 0)) { + 0, NULL)) { remove_extent_mapping(map, em); /* once for the rb tree */ free_extent_map(em); @@ -3237,7 +3253,7 @@ int extent_range_uptodate(struct extent_io_tree *tree, int uptodate; unsigned long index; - ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1); + ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL); if (ret) return 1; while (start <= end) { @@ -3267,7 +3283,7 @@ int extent_buffer_uptodate(struct extent_io_tree *tree, return 1; ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1, - EXTENT_UPTODATE, 1); + EXTENT_UPTODATE, 1, NULL); if (ret) return ret; @@ -3303,7 +3319,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree, return 0; if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, - EXTENT_UPTODATE, 1)) { + EXTENT_UPTODATE, 1, NULL)) { return 0; } diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index c8ead2b8c4c..09cd6fa3cc8 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -157,7 +157,7 @@ u64 count_range_bits(struct extent_io_tree *tree, u64 max_bytes, unsigned long bits); int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, - int bits, int filled); + int bits, int filled, struct extent_state *cached_state); int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits, gfp_t mask); int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index e494545c420..3f8e93de298 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1376,7 +1376,7 @@ again: /* already ordered? We're done */ if (test_range_bit(&BTRFS_I(inode)->io_tree, page_start, page_end, - EXTENT_ORDERED, 0)) { + EXTENT_ORDERED, 0, NULL)) { goto out; } @@ -1417,7 +1417,7 @@ static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end) int ret; ret = test_range_bit(&BTRFS_I(inode)->io_tree, start, end, - EXTENT_ORDERED, 0); + EXTENT_ORDERED, 0, NULL); if (ret) return 0; @@ -1795,7 +1795,7 @@ static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end, return 0; if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID && - test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1)) { + test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) { clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM, GFP_NOFS); return 0; diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index d6f0806c682..7f751e462f0 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -262,7 +262,7 @@ int btrfs_dec_test_ordered_pending(struct inode *inode, ret = test_range_bit(io_tree, entry->file_offset, entry->file_offset + entry->len - 1, - EXTENT_ORDERED, 0); + EXTENT_ORDERED, 0, NULL); if (ret == 0) ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); out: @@ -522,7 +522,7 @@ again: end--; } if (test_range_bit(&BTRFS_I(inode)->io_tree, start, orig_end, - EXTENT_ORDERED | EXTENT_DELALLOC, 0)) { + EXTENT_ORDERED | EXTENT_DELALLOC, 0, NULL)) { schedule_timeout(1); goto again; } @@ -613,7 +613,7 @@ int btrfs_ordered_update_i_size(struct inode *inode, */ if (test_range_bit(io_tree, disk_i_size, ordered->file_offset + ordered->len - 1, - EXTENT_DELALLOC, 0)) { + EXTENT_DELALLOC, 0, NULL)) { goto out; } /* @@ -664,7 +664,7 @@ int btrfs_ordered_update_i_size(struct inode *inode, */ if (i_size_test > entry_end(ordered) && !test_range_bit(io_tree, entry_end(ordered), i_size_test - 1, - EXTENT_DELALLOC, 0)) { + EXTENT_DELALLOC, 0, NULL)) { new_i_size = min_t(u64, i_size_test, i_size_read(inode)); } BTRFS_I(inode)->disk_i_size = new_i_size; diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 4adab903fc2..3be16ccc7ee 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -2180,7 +2180,7 @@ static int tree_block_processed(u64 bytenr, u32 blocksize, struct reloc_control *rc) { if (test_range_bit(&rc->processed_blocks, bytenr, - bytenr + blocksize - 1, EXTENT_DIRTY, 1)) + bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL)) return 1; return 0; } -- cgit v1.2.3-70-g09d2 From 8b62b72b26bcd72082c4a69d179dd906bcc22200 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Wed, 2 Sep 2009 16:53:46 -0400 Subject: Btrfs: Use PagePrivate2 to track pages in the data=ordered code. Btrfs writes go through delalloc to the data=ordered code. This makes sure that all of the data is on disk before the metadata that references it. The tracking means that we have to make sure each page in an extent is fully written before we add that extent into the on-disk btree. This was done in the past by setting the EXTENT_ORDERED bit for the range of an extent when it was added to the data=ordered code, and then clearing the EXTENT_ORDERED bit in the extent state tree as each page finished IO. One of the reasons we had to do this was because sometimes pages are magically dirtied without page_mkwrite being called. The EXTENT_ORDERED bit is checked at writepage time, and if it isn't there, our page become dirty without going through the proper path. These bit operations make for a number of rbtree searches for each page, and can cause considerable lock contention. This commit switches from the EXTENT_ORDERED bit to use PagePrivate2. As pages go into the ordered code, PagePrivate2 is set on each one. This is a cheap operation because we already have all the pages locked and ready to go. As IO finishes, the PagePrivate2 bit is cleared and the ordered accoutning is updated for each page. At writepage time, if the PagePrivate2 bit is missing, we go into the writepage fixup code to handle improperly dirtied pages. Signed-off-by: Chris Mason --- fs/btrfs/extent_io.c | 29 ++++++++++------------------- fs/btrfs/extent_io.h | 9 ++++----- fs/btrfs/inode.c | 47 ++++++++++++++++++++++++++++++----------------- fs/btrfs/ordered-data.c | 29 +++++++++++++++-------------- fs/btrfs/ordered-data.h | 3 +++ 5 files changed, 62 insertions(+), 55 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index c9a438d374b..a102422cd92 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -885,13 +885,6 @@ int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, NULL, mask); } -int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, NULL, - mask); -} - int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits, gfp_t mask) { @@ -921,13 +914,6 @@ int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, NULL, mask); } -int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, - NULL, mask); -} - int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { @@ -1373,7 +1359,8 @@ int extent_clear_unlock_delalloc(struct inode *inode, int clear_unlock, int clear_delalloc, int clear_dirty, int set_writeback, - int end_writeback) + int end_writeback, + int set_private2) { int ret; struct page *pages[16]; @@ -1392,7 +1379,8 @@ int extent_clear_unlock_delalloc(struct inode *inode, clear_bits |= EXTENT_DELALLOC; clear_extent_bit(tree, start, end, clear_bits, 1, 0, NULL, GFP_NOFS); - if (!(unlock_pages || clear_dirty || set_writeback || end_writeback)) + if (!(unlock_pages || clear_dirty || set_writeback || end_writeback || + set_private2)) return 0; while (nr_pages > 0) { @@ -1400,6 +1388,10 @@ int extent_clear_unlock_delalloc(struct inode *inode, min_t(unsigned long, nr_pages, ARRAY_SIZE(pages)), pages); for (i = 0; i < ret; i++) { + + if (set_private2) + SetPagePrivate2(pages[i]); + if (pages[i] == locked_page) { page_cache_release(pages[i]); continue; @@ -2792,7 +2784,7 @@ int try_release_extent_state(struct extent_map_tree *map, int ret = 1; if (test_range_bit(tree, start, end, - EXTENT_IOBITS | EXTENT_ORDERED, 0, NULL)) + EXTENT_IOBITS, 0, NULL)) ret = 0; else { if ((mask & GFP_NOFS) == GFP_NOFS) @@ -2835,8 +2827,7 @@ int try_release_extent_mapping(struct extent_map_tree *map, } if (!test_range_bit(tree, em->start, extent_map_end(em) - 1, - EXTENT_LOCKED | EXTENT_WRITEBACK | - EXTENT_ORDERED, + EXTENT_LOCKED | EXTENT_WRITEBACK, 0, NULL)) { remove_extent_mapping(map, em); /* once for the rb tree */ diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 09cd6fa3cc8..14ed16fd862 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -13,10 +13,8 @@ #define EXTENT_DEFRAG (1 << 6) #define EXTENT_DEFRAG_DONE (1 << 7) #define EXTENT_BUFFER_FILLED (1 << 8) -#define EXTENT_ORDERED (1 << 9) -#define EXTENT_ORDERED_METADATA (1 << 10) -#define EXTENT_BOUNDARY (1 << 11) -#define EXTENT_NODATASUM (1 << 12) +#define EXTENT_BOUNDARY (1 << 9) +#define EXTENT_NODATASUM (1 << 10) #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK) /* flags for bio submission */ @@ -285,5 +283,6 @@ int extent_clear_unlock_delalloc(struct inode *inode, int clear_unlock, int clear_delalloc, int clear_dirty, int set_writeback, - int end_writeback); + int end_writeback, + int set_private2); #endif diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 3f8e93de298..739a245e25d 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -426,7 +426,7 @@ again: extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, start, end, NULL, 1, 0, - 0, 1, 1, 1); + 0, 1, 1, 1, 0); ret = 0; goto free_pages_out; } @@ -641,7 +641,7 @@ static noinline int submit_compressed_extents(struct inode *inode, async_extent->start, async_extent->start + async_extent->ram_size - 1, - NULL, 1, 1, 0, 1, 1, 0); + NULL, 1, 1, 0, 1, 1, 0, 0); ret = btrfs_submit_compressed_write(inode, async_extent->start, @@ -714,7 +714,7 @@ static noinline int cow_file_range(struct inode *inode, extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, start, end, NULL, 1, 1, - 1, 1, 1, 1); + 1, 1, 1, 1, 0); *nr_written = *nr_written + (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE; *page_started = 1; @@ -777,11 +777,14 @@ static noinline int cow_file_range(struct inode *inode, /* we're not doing compressed IO, don't unlock the first * page (which the caller expects to stay locked), don't * clear any dirty bits and don't set any writeback bits + * + * Do set the Private2 bit so we know this page was properly + * setup for writepage */ extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, start, start + ram_size - 1, locked_page, unlock, 1, - 1, 0, 0, 0); + 1, 0, 0, 0, 1); disk_num_bytes -= cur_alloc_size; num_bytes -= cur_alloc_size; alloc_hint = ins.objectid + ins.offset; @@ -1102,7 +1105,7 @@ out_check: extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, cur_offset, cur_offset + num_bytes - 1, - locked_page, 1, 1, 1, 0, 0, 0); + locked_page, 1, 1, 1, 0, 0, 0, 1); cur_offset = extent_end; if (cur_offset > end) break; @@ -1375,10 +1378,8 @@ again: lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS); /* already ordered? We're done */ - if (test_range_bit(&BTRFS_I(inode)->io_tree, page_start, page_end, - EXTENT_ORDERED, 0, NULL)) { + if (PagePrivate2(page)) goto out; - } ordered = btrfs_lookup_ordered_extent(inode, page_start); if (ordered) { @@ -1414,11 +1415,9 @@ static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end) struct inode *inode = page->mapping->host; struct btrfs_writepage_fixup *fixup; struct btrfs_root *root = BTRFS_I(inode)->root; - int ret; - ret = test_range_bit(&BTRFS_I(inode)->io_tree, start, end, - EXTENT_ORDERED, 0, NULL); - if (ret) + /* this page is properly in the ordered list */ + if (TestClearPagePrivate2(page)) return 0; if (PageChecked(page)) @@ -1624,6 +1623,7 @@ nocow: static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, struct extent_state *state, int uptodate) { + ClearPagePrivate2(page); return btrfs_finish_ordered_io(page->mapping->host, start, end); } @@ -4403,13 +4403,21 @@ static void btrfs_invalidatepage(struct page *page, unsigned long offset) u64 page_start = page_offset(page); u64 page_end = page_start + PAGE_CACHE_SIZE - 1; + + /* + * we have the page locked, so new writeback can't start, + * and the dirty bit won't be cleared while we are here. + * + * Wait for IO on this page so that we can safely clear + * the PagePrivate2 bit and do ordered accounting + */ wait_on_page_writeback(page); + tree = &BTRFS_I(page->mapping->host)->io_tree; if (offset) { btrfs_releasepage(page, GFP_NOFS); return; } - lock_extent(tree, page_start, page_end, GFP_NOFS); ordered = btrfs_lookup_ordered_extent(page->mapping->host, page_offset(page)); @@ -4421,14 +4429,19 @@ static void btrfs_invalidatepage(struct page *page, unsigned long offset) clear_extent_bit(tree, page_start, page_end, EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_LOCKED, 1, 0, NULL, GFP_NOFS); - btrfs_finish_ordered_io(page->mapping->host, - page_start, page_end); + /* + * whoever cleared the private bit is responsible + * for the finish_ordered_io + */ + if (TestClearPagePrivate2(page)) { + btrfs_finish_ordered_io(page->mapping->host, + page_start, page_end); + } btrfs_put_ordered_extent(ordered); lock_extent(tree, page_start, page_end, GFP_NOFS); } clear_extent_bit(tree, page_start, page_end, - EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC | - EXTENT_ORDERED, + EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, 1, 1, NULL, GFP_NOFS); __btrfs_releasepage(page, GFP_NOFS); diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index 7f751e462f0..4a9c8c4cec2 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -159,8 +159,6 @@ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree, * * len is the length of the extent * - * This also sets the EXTENT_ORDERED bit on the range in the inode. - * * The tree is given a single reference on the ordered extent that was * inserted. */ @@ -181,6 +179,7 @@ int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset, entry->start = start; entry->len = len; entry->disk_len = disk_len; + entry->bytes_left = len; entry->inode = inode; if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE) set_bit(type, &entry->flags); @@ -195,9 +194,6 @@ int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset, &entry->rb_node); BUG_ON(node); - set_extent_ordered(&BTRFS_I(inode)->io_tree, file_offset, - entry_end(entry) - 1, GFP_NOFS); - spin_lock(&BTRFS_I(inode)->root->fs_info->ordered_extent_lock); list_add_tail(&entry->root_extent_list, &BTRFS_I(inode)->root->fs_info->ordered_extents); @@ -241,13 +237,10 @@ int btrfs_dec_test_ordered_pending(struct inode *inode, struct btrfs_ordered_inode_tree *tree; struct rb_node *node; struct btrfs_ordered_extent *entry; - struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; int ret; tree = &BTRFS_I(inode)->ordered_tree; mutex_lock(&tree->mutex); - clear_extent_ordered(io_tree, file_offset, file_offset + io_size - 1, - GFP_NOFS); node = tree_search(tree, file_offset); if (!node) { ret = 1; @@ -260,11 +253,16 @@ int btrfs_dec_test_ordered_pending(struct inode *inode, goto out; } - ret = test_range_bit(io_tree, entry->file_offset, - entry->file_offset + entry->len - 1, - EXTENT_ORDERED, 0, NULL); - if (ret == 0) + if (io_size > entry->bytes_left) { + printk(KERN_CRIT "bad ordered accounting left %llu size %llu\n", + (unsigned long long)entry->bytes_left, + (unsigned long long)io_size); + } + entry->bytes_left -= io_size; + if (entry->bytes_left == 0) ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); + else + ret = 1; out: mutex_unlock(&tree->mutex); return ret == 0; @@ -476,6 +474,7 @@ int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len) u64 orig_end; u64 wait_end; struct btrfs_ordered_extent *ordered; + int found; if (start + len < start) { orig_end = INT_LIMIT(loff_t); @@ -502,6 +501,7 @@ again: orig_end >> PAGE_CACHE_SHIFT); end = orig_end; + found = 0; while (1) { ordered = btrfs_lookup_first_ordered_extent(inode, end); if (!ordered) @@ -514,6 +514,7 @@ again: btrfs_put_ordered_extent(ordered); break; } + found++; btrfs_start_ordered_extent(inode, ordered, 1); end = ordered->file_offset; btrfs_put_ordered_extent(ordered); @@ -521,8 +522,8 @@ again: break; end--; } - if (test_range_bit(&BTRFS_I(inode)->io_tree, start, orig_end, - EXTENT_ORDERED | EXTENT_DELALLOC, 0, NULL)) { + if (found || test_range_bit(&BTRFS_I(inode)->io_tree, start, orig_end, + EXTENT_DELALLOC, 0, NULL)) { schedule_timeout(1); goto again; } diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h index 3d31c8827b0..993a7ea45c7 100644 --- a/fs/btrfs/ordered-data.h +++ b/fs/btrfs/ordered-data.h @@ -85,6 +85,9 @@ struct btrfs_ordered_extent { /* extent length on disk */ u64 disk_len; + /* number of bytes that still need writing */ + u64 bytes_left; + /* flags (described above) */ unsigned long flags; -- cgit v1.2.3-70-g09d2 From a1ed835e1ab5795f91b198d08c43e2f56848dcf3 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Fri, 11 Sep 2009 12:27:37 -0400 Subject: Btrfs: Fix extent replacment race Data COW means that whenever we write to a file, we replace any old extent pointers with new ones. There was a window where a readpage might find the old extent pointers on disk and cache them in the extent_map tree in ram in the middle of a given write replacing them. Even though both the readpage and the write had their respective bytes in the file locked, the extent readpage inserts may cover more bytes than it had locked down. This commit closes the race by keeping the new extent pinned in the extent map tree until after the on-disk btree is properly setup with the new extent pointers. Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 2 +- fs/btrfs/extent_map.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/extent_map.h | 1 + fs/btrfs/file.c | 8 +++++--- fs/btrfs/inode.c | 25 ++++++++++++++++++++----- fs/btrfs/ioctl.c | 5 ++--- fs/btrfs/tree-log.c | 2 +- 7 files changed, 80 insertions(+), 13 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 38eeb6c49c8..1ceab8b4d6d 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2292,7 +2292,7 @@ extern struct file_operations btrfs_file_operations; int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 start, u64 end, u64 locked_end, - u64 inline_limit, u64 *hint_block); + u64 inline_limit, u64 *hint_block, int drop_cache); int btrfs_mark_extent_written(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 start, u64 end); diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 72e9fa3c31f..5bc7a0d325e 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -198,6 +198,56 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next) return 0; } +int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len) +{ + int ret = 0; + struct extent_map *merge = NULL; + struct rb_node *rb; + struct extent_map *em; + + write_lock(&tree->lock); + em = lookup_extent_mapping(tree, start, len); + + WARN_ON(em->start != start || !em); + + if (!em) + goto out; + + clear_bit(EXTENT_FLAG_PINNED, &em->flags); + + if (em->start != 0) { + rb = rb_prev(&em->rb_node); + if (rb) + merge = rb_entry(rb, struct extent_map, rb_node); + if (rb && mergable_maps(merge, em)) { + em->start = merge->start; + em->len += merge->len; + em->block_len += merge->block_len; + em->block_start = merge->block_start; + merge->in_tree = 0; + rb_erase(&merge->rb_node, &tree->map); + free_extent_map(merge); + } + } + + rb = rb_next(&em->rb_node); + if (rb) + merge = rb_entry(rb, struct extent_map, rb_node); + if (rb && mergable_maps(em, merge)) { + em->len += merge->len; + em->block_len += merge->len; + rb_erase(&merge->rb_node, &tree->map); + merge->in_tree = 0; + free_extent_map(merge); + } + + free_extent_map(em); +out: + write_unlock(&tree->lock); + return ret; + +} + /** * add_extent_mapping - add new extent map to the extent tree * @tree: tree to insert new map in diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h index 6216dfbcf9b..d3d442f4bbb 100644 --- a/fs/btrfs/extent_map.h +++ b/fs/btrfs/extent_map.h @@ -59,4 +59,5 @@ struct extent_map *alloc_extent_map(gfp_t mask); void free_extent_map(struct extent_map *em); int __init extent_map_init(void); void extent_map_exit(void); +int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len); #endif diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index ef66c3d989b..4123db9d514 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -177,10 +177,10 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, } flags = em->flags; if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) { - write_unlock(&em_tree->lock); if (em->start <= start && (!testend || em->start + em->len >= start + len)) { free_extent_map(em); + write_unlock(&em_tree->lock); break; } if (start < em->start) { @@ -190,6 +190,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, start = em->start + em->len; } free_extent_map(em); + write_unlock(&em_tree->lock); continue; } compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); @@ -269,7 +270,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, noinline int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 start, u64 end, u64 locked_end, - u64 inline_limit, u64 *hint_byte) + u64 inline_limit, u64 *hint_byte, int drop_cache) { u64 extent_end = 0; u64 search_start = start; @@ -294,7 +295,8 @@ noinline int btrfs_drop_extents(struct btrfs_trans_handle *trans, int ret; inline_limit = 0; - btrfs_drop_extent_cache(inode, start, end - 1, 0); + if (drop_cache) + btrfs_drop_extent_cache(inode, start, end - 1, 0); path = btrfs_alloc_path(); if (!path) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 739a245e25d..233fe6f2612 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -232,7 +232,8 @@ static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans, } ret = btrfs_drop_extents(trans, root, inode, start, - aligned_end, aligned_end, start, &hint_byte); + aligned_end, aligned_end, start, + &hint_byte, 1); BUG_ON(ret); if (isize > actual_end) @@ -241,7 +242,7 @@ static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans, inline_len, compressed_size, compressed_pages); BUG_ON(ret); - btrfs_drop_extent_cache(inode, start, aligned_end, 0); + btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0); return 0; } @@ -1455,9 +1456,19 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, BUG_ON(!path); path->leave_spinning = 1; + + /* + * we may be replacing one extent in the tree with another. + * The new extent is pinned in the extent map, and we don't want + * to drop it from the cache until it is completely in the btree. + * + * So, tell btrfs_drop_extents to leave this extent in the cache. + * the caller is expected to unpin it and allow it to be merged + * with the others. + */ ret = btrfs_drop_extents(trans, root, inode, file_pos, file_pos + num_bytes, locked_end, - file_pos, &hint); + file_pos, &hint, 0); BUG_ON(ret); ins.objectid = inode->i_ino; @@ -1485,7 +1496,6 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(leaf); inode_add_bytes(inode, num_bytes); - btrfs_drop_extent_cache(inode, file_pos, file_pos + num_bytes - 1, 0); ins.objectid = disk_bytenr; ins.offset = disk_num_bytes; @@ -1596,6 +1606,9 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) ordered_extent->len, compressed, 0, 0, BTRFS_FILE_EXTENT_REG); + unpin_extent_cache(&BTRFS_I(inode)->extent_tree, + ordered_extent->file_offset, + ordered_extent->len); BUG_ON(ret); } unlock_extent(io_tree, ordered_extent->file_offset, @@ -2940,7 +2953,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t size) cur_offset, cur_offset + hole_size, block_end, - cur_offset, &hint_byte); + cur_offset, &hint_byte, 1); if (err) break; err = btrfs_insert_file_extent(trans, root, @@ -5086,6 +5099,8 @@ static int prealloc_file_range(struct btrfs_trans_handle *trans, 0, 0, 0, BTRFS_FILE_EXTENT_PREALLOC); BUG_ON(ret); + btrfs_drop_extent_cache(inode, cur_offset, + cur_offset + ins.offset -1, 0); num_bytes -= ins.offset; cur_offset += ins.offset; alloc_hint = ins.objectid + ins.offset; diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 9f4db848db1..e2d8e90259b 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -597,9 +597,8 @@ again: clear_page_dirty_for_io(page); btrfs_set_extent_delalloc(inode, page_start, page_end); - - unlock_extent(io_tree, page_start, page_end, GFP_NOFS); set_page_dirty(page); + unlock_extent(io_tree, page_start, page_end, GFP_NOFS); unlock_page(page); page_cache_release(page); balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1); @@ -977,7 +976,7 @@ static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, /* punch hole in destination first */ btrfs_drop_extents(trans, root, inode, off, off + len, - off + len, 0, &hint_byte); + off + len, 0, &hint_byte, 1); /* clone data */ key.objectid = src->i_ino; diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index d91b0de7c50..8661a7381b3 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -534,7 +534,7 @@ static noinline int replay_one_extent(struct btrfs_trans_handle *trans, saved_nbytes = inode_get_bytes(inode); /* drop any overlapping extents */ ret = btrfs_drop_extents(trans, root, inode, - start, extent_end, extent_end, start, &alloc_hint); + start, extent_end, extent_end, start, &alloc_hint, 1); BUG_ON(ret); if (found_type == BTRFS_FILE_EXTENT_REG || -- cgit v1.2.3-70-g09d2 From 50a9b214bc6c052caa05a210ebfc1bdf0d7085b2 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Fri, 11 Sep 2009 12:33:12 -0400 Subject: Btrfs: fix btrfs page_mkwrite to return locked page This closes a whole where the page may be written before the page_mkwrite caller has a chance to dirty it (thanks to Nick Piggin) Signed-off-by: Chris Mason --- fs/btrfs/inode.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 233fe6f2612..c846482e798 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4552,11 +4552,14 @@ again: } ClearPageChecked(page); set_page_dirty(page); + SetPageUptodate(page); BTRFS_I(inode)->last_trans = root->fs_info->generation + 1; unlock_extent(io_tree, page_start, page_end, GFP_NOFS); out_unlock: + if (!ret) + return VM_FAULT_LOCKED; unlock_page(page); out: return ret; -- cgit v1.2.3-70-g09d2 From 93c82d575055f1bd0277acae6f966bebafd80dd5 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Fri, 11 Sep 2009 12:36:29 -0400 Subject: Btrfs: zero page past end of inline file items When btrfs_get_extent is reading inline file items for readpage, it needs to copy the inline extent into the page. If the inline extent doesn't cover all of the page, that means there is a hole in the file, or that our file is smaller than one page. readpage does zeroing for the case where the file is smaller than one page, but nobody is currently zeroing for the case where there is a hole after the inline item. This commit changes btrfs_get_extent to zero fill the page past the end of the inline item. Signed-off-by: Chris Mason --- fs/btrfs/inode.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index c846482e798..88f9df7bfda 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4233,6 +4233,11 @@ again: map = kmap(page); read_extent_buffer(leaf, map + pg_offset, ptr, copy_size); + if (pg_offset + copy_size < PAGE_CACHE_SIZE) { + memset(map + pg_offset + copy_size, 0, + PAGE_CACHE_SIZE - pg_offset - + copy_size); + } kunmap(page); } flush_dcache_page(page); -- cgit v1.2.3-70-g09d2 From b917b7c3be50435fa8257591b964934e917f2d45 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Fri, 18 Sep 2009 16:07:03 -0400 Subject: Btrfs: search for an allocation hint while filling file COW The allocator has some nice knobs for sending hints about where to try and allocate new blocks, but when we're doing file allocations we're not sending any hint at all. This commit adds a simple extent map search to see if we can quickly and easily find a hint for the allocator. Signed-off-by: Chris Mason --- fs/btrfs/extent_map.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/extent_map.h | 2 ++ fs/btrfs/inode.c | 10 +++++++++- 3 files changed, 59 insertions(+), 1 deletion(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 5bc7a0d325e..2c726b7b9fa 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -366,6 +366,54 @@ out: return em; } +/** + * search_extent_mapping - find a nearby extent map + * @tree: tree to lookup in + * @start: byte offset to start the search + * @len: length of the lookup range + * + * Find and return the first extent_map struct in @tree that intersects the + * [start, len] range. + * + * If one can't be found, any nearby extent may be returned + */ +struct extent_map *search_extent_mapping(struct extent_map_tree *tree, + u64 start, u64 len) +{ + struct extent_map *em; + struct rb_node *rb_node; + struct rb_node *prev = NULL; + struct rb_node *next = NULL; + + rb_node = __tree_search(&tree->map, start, &prev, &next); + if (!rb_node && prev) { + em = rb_entry(prev, struct extent_map, rb_node); + goto found; + } + if (!rb_node && next) { + em = rb_entry(next, struct extent_map, rb_node); + goto found; + } + if (!rb_node) { + em = NULL; + goto out; + } + if (IS_ERR(rb_node)) { + em = ERR_PTR(PTR_ERR(rb_node)); + goto out; + } + em = rb_entry(rb_node, struct extent_map, rb_node); + goto found; + + em = NULL; + goto out; + +found: + atomic_inc(&em->refs); +out: + return em; +} + /** * remove_extent_mapping - removes an extent_map from the extent tree * @tree: extent tree to remove from diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h index d3d442f4bbb..ab6d74b6e64 100644 --- a/fs/btrfs/extent_map.h +++ b/fs/btrfs/extent_map.h @@ -60,4 +60,6 @@ void free_extent_map(struct extent_map *em); int __init extent_map_init(void); void extent_map_exit(void); int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len); +struct extent_map *search_extent_mapping(struct extent_map_tree *tree, + u64 start, u64 len); #endif diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 941f1b71cd2..81ba6654c33 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -726,6 +726,15 @@ static noinline int cow_file_range(struct inode *inode, BUG_ON(disk_num_bytes > btrfs_super_total_bytes(&root->fs_info->super_copy)); + + read_lock(&BTRFS_I(inode)->extent_tree.lock); + em = search_extent_mapping(&BTRFS_I(inode)->extent_tree, + start, num_bytes); + if (em) { + alloc_hint = em->block_start; + free_extent_map(em); + } + read_unlock(&BTRFS_I(inode)->extent_tree.lock); btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); while (disk_num_bytes > 0) { @@ -738,7 +747,6 @@ static noinline int cow_file_range(struct inode *inode, em = alloc_extent_map(GFP_NOFS); em->start = start; em->orig_start = em->start; - ram_size = ins.offset; em->len = ins.offset; -- cgit v1.2.3-70-g09d2 From 13a8a7c8c47e542b3cdb45bec3f431f96af79361 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Mon, 21 Sep 2009 15:56:00 -0400 Subject: Btrfs: do not reuse objectid of deleted snapshot/subvol The new back reference format does not allow reusing objectid of deleted snapshot/subvol. So we use ++highest_objectid to allocate objectid for new snapshot/subvol. Now we use ++highest_objectid to allocate objectid for both new inode and new snapshot/subvolume, so this patch removes 'find hole' code in btrfs_find_free_objectid. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 4 +-- fs/btrfs/disk-io.c | 39 ++++++++------------- fs/btrfs/inode-item.c | 2 -- fs/btrfs/inode-map.c | 93 +++++++++------------------------------------------ fs/btrfs/inode.c | 3 -- fs/btrfs/tree-log.c | 6 ---- 6 files changed, 31 insertions(+), 116 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 3b6df714057..746a9acd218 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1007,8 +1007,8 @@ struct btrfs_root { u32 stripesize; u32 type; - u64 highest_inode; - u64 last_inode_alloc; + + u64 highest_objectid; int ref_cows; int track_dirty; u64 defrag_trans_start; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 16dae122dda..790f4b61a3d 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -895,8 +895,7 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize, root->fs_info = fs_info; root->objectid = objectid; root->last_trans = 0; - root->highest_inode = 0; - root->last_inode_alloc = 0; + root->highest_objectid = 0; root->name = NULL; root->in_sysfs = 0; root->inode_tree.rb_node = NULL; @@ -1095,7 +1094,6 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root, struct btrfs_fs_info *fs_info = tree_root->fs_info; struct btrfs_path *path; struct extent_buffer *l; - u64 highest_inode; u64 generation; u32 blocksize; int ret = 0; @@ -1110,7 +1108,7 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root, kfree(root); return ERR_PTR(ret); } - goto insert; + goto out; } __setup_root(tree_root->nodesize, tree_root->leafsize, @@ -1120,39 +1118,30 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root, path = btrfs_alloc_path(); BUG_ON(!path); ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0); - if (ret != 0) { - if (ret > 0) - ret = -ENOENT; - goto out; + if (ret == 0) { + l = path->nodes[0]; + read_extent_buffer(l, &root->root_item, + btrfs_item_ptr_offset(l, path->slots[0]), + sizeof(root->root_item)); + memcpy(&root->root_key, location, sizeof(*location)); } - l = path->nodes[0]; - read_extent_buffer(l, &root->root_item, - btrfs_item_ptr_offset(l, path->slots[0]), - sizeof(root->root_item)); - memcpy(&root->root_key, location, sizeof(*location)); - ret = 0; -out: - btrfs_release_path(root, path); btrfs_free_path(path); if (ret) { - kfree(root); + if (ret > 0) + ret = -ENOENT; return ERR_PTR(ret); } + generation = btrfs_root_generation(&root->root_item); blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item)); root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item), blocksize, generation); root->commit_root = btrfs_root_node(root); BUG_ON(!root->node); -insert: - if (location->objectid != BTRFS_TREE_LOG_OBJECTID) { +out: + if (location->objectid != BTRFS_TREE_LOG_OBJECTID) root->ref_cows = 1; - ret = btrfs_find_highest_inode(root, &highest_inode); - if (ret == 0) { - root->highest_inode = highest_inode; - root->last_inode_alloc = highest_inode; - } - } + return root; } diff --git a/fs/btrfs/inode-item.c b/fs/btrfs/inode-item.c index 6b627c61180..fc6f4a7f640 100644 --- a/fs/btrfs/inode-item.c +++ b/fs/btrfs/inode-item.c @@ -177,8 +177,6 @@ int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans, ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(struct btrfs_inode_item)); - if (ret == 0 && objectid > root->highest_inode) - root->highest_inode = objectid; return ret; } diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c index 9abbced1123..c56eb590917 100644 --- a/fs/btrfs/inode-map.c +++ b/fs/btrfs/inode-map.c @@ -43,9 +43,10 @@ int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid) slot = path->slots[0] - 1; l = path->nodes[0]; btrfs_item_key_to_cpu(l, &found_key, slot); - *objectid = found_key.objectid; + *objectid = max_t(u64, found_key.objectid, + BTRFS_FIRST_FREE_OBJECTID - 1); } else { - *objectid = BTRFS_FIRST_FREE_OBJECTID; + *objectid = BTRFS_FIRST_FREE_OBJECTID - 1; } ret = 0; error: @@ -53,91 +54,27 @@ error: return ret; } -/* - * walks the btree of allocated inodes and find a hole. - */ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 dirid, u64 *objectid) { - struct btrfs_path *path; - struct btrfs_key key; int ret; - int slot = 0; - u64 last_ino = 0; - int start_found; - struct extent_buffer *l; - struct btrfs_key search_key; - u64 search_start = dirid; - mutex_lock(&root->objectid_mutex); - if (root->last_inode_alloc >= BTRFS_FIRST_FREE_OBJECTID && - root->last_inode_alloc < BTRFS_LAST_FREE_OBJECTID) { - *objectid = ++root->last_inode_alloc; - mutex_unlock(&root->objectid_mutex); - return 0; - } - path = btrfs_alloc_path(); - BUG_ON(!path); - search_start = max(search_start, (u64)BTRFS_FIRST_FREE_OBJECTID); - search_key.objectid = search_start; - search_key.type = 0; - search_key.offset = 0; - - start_found = 0; - ret = btrfs_search_slot(trans, root, &search_key, path, 0, 0); - if (ret < 0) - goto error; - while (1) { - l = path->nodes[0]; - slot = path->slots[0]; - if (slot >= btrfs_header_nritems(l)) { - ret = btrfs_next_leaf(root, path); - if (ret == 0) - continue; - if (ret < 0) - goto error; - if (!start_found) { - *objectid = search_start; - start_found = 1; - goto found; - } - *objectid = last_ino > search_start ? - last_ino : search_start; - goto found; - } - btrfs_item_key_to_cpu(l, &key, slot); - if (key.objectid >= search_start) { - if (start_found) { - if (last_ino < search_start) - last_ino = search_start; - if (key.objectid > last_ino) { - *objectid = last_ino; - goto found; - } - } else if (key.objectid > search_start) { - *objectid = search_start; - goto found; - } - } - if (key.objectid >= BTRFS_LAST_FREE_OBJECTID) - break; + if (unlikely(root->highest_objectid < BTRFS_FIRST_FREE_OBJECTID)) { + ret = btrfs_find_highest_inode(root, &root->highest_objectid); + if (ret) + goto out; + } - start_found = 1; - last_ino = key.objectid + 1; - path->slots[0]++; + if (unlikely(root->highest_objectid >= BTRFS_LAST_FREE_OBJECTID)) { + ret = -ENOSPC; + goto out; } - BUG_ON(1); -found: - btrfs_release_path(root, path); - btrfs_free_path(path); - BUG_ON(*objectid < search_start); - mutex_unlock(&root->objectid_mutex); - return 0; -error: - btrfs_release_path(root, path); - btrfs_free_path(path); + + *objectid = ++root->highest_objectid; + ret = 0; +out: mutex_unlock(&root->objectid_mutex); return ret; } diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 81ba6654c33..9e81f3184f2 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3624,9 +3624,6 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, if (ret != 0) goto fail; - if (objectid > root->highest_inode) - root->highest_inode = objectid; - inode->i_uid = current_fsuid(); if (dir && (dir->i_mode & S_ISGID)) { diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index f4a7b62f9be..6e674d76186 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -2951,7 +2951,6 @@ int btrfs_recover_log_trees(struct btrfs_root *log_root_tree) struct btrfs_key tmp_key; struct btrfs_root *log; struct btrfs_fs_info *fs_info = log_root_tree->fs_info; - u64 highest_inode; struct walk_control wc = { .process_func = process_one_buffer, .stage = 0, @@ -3010,11 +3009,6 @@ again: path); BUG_ON(ret); } - ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode); - if (ret == 0) { - wc.replay_dest->highest_inode = highest_inode; - wc.replay_dest->last_inode_alloc = highest_inode; - } key.offset = found_key.offset - 1; wc.replay_dest->log_root = NULL; -- cgit v1.2.3-70-g09d2 From 4df27c4d5cc1dda54ed7d0a8389347f2df359cf9 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Mon, 21 Sep 2009 15:56:00 -0400 Subject: Btrfs: change how subvolumes are organized btrfs allows subvolumes and snapshots anywhere in the directory tree. If we snapshot a subvolume that contains a link to other subvolume called subvolA, subvolA can be accessed through both the original subvolume and the snapshot. This is similar to creating hard link to directory, and has the very similar problems. The aim of this patch is enforcing there is only one access point to each subvolume. Only the first directory entry (the one added when the subvolume/snapshot was created) is treated as valid access point. The first directory entry is distinguished by checking root forward reference. If the corresponding root forward reference is missing, we know the entry is not the first one. This patch also adds snapshot/subvolume rename support, the code allows rename subvolume link across subvolumes. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/btrfs_inode.h | 1 + fs/btrfs/ctree.h | 28 +++- fs/btrfs/dir-item.c | 47 +++++++ fs/btrfs/disk-io.c | 71 +++++++--- fs/btrfs/inode.c | 368 +++++++++++++++++++++++++++++++++++-------------- fs/btrfs/ioctl.c | 13 +- fs/btrfs/orphan.c | 20 +++ fs/btrfs/root-tree.c | 69 +++++++--- fs/btrfs/transaction.c | 10 -- 9 files changed, 459 insertions(+), 168 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index ea1ea0af8c0..82ee56bba29 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -138,6 +138,7 @@ struct btrfs_inode { * of these. */ unsigned ordered_data_close:1; + unsigned dummy_inode:1; struct inode vfs_inode; }; diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 746a9acd218..6ade48b227e 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -114,6 +114,10 @@ struct btrfs_ordered_sum; */ #define BTRFS_DEV_ITEMS_OBJECTID 1ULL +#define BTRFS_BTREE_INODE_OBJECTID 1 + +#define BTRFS_EMPTY_SUBVOL_DIR_OBJECTID 2 + /* * we can actually store much bigger names, but lets not confuse the rest * of linux @@ -792,6 +796,8 @@ struct btrfs_fs_info { /* the log root tree is a directory of all the other log roots */ struct btrfs_root *log_root_tree; + + spinlock_t fs_roots_radix_lock; struct radix_tree_root fs_roots_radix; /* block group cache stuff */ @@ -1011,6 +1017,8 @@ struct btrfs_root { u64 highest_objectid; int ref_cows; int track_dirty; + int in_radix; + u64 defrag_trans_start; struct btrfs_key defrag_progress; struct btrfs_key defrag_max; @@ -2111,12 +2119,15 @@ int btrfs_drop_subtree(struct btrfs_trans_handle *trans, struct extent_buffer *parent); /* root-item.c */ int btrfs_find_root_ref(struct btrfs_root *tree_root, - struct btrfs_path *path, - u64 root_id, u64 ref_id); + struct btrfs_path *path, + u64 root_id, u64 ref_id); int btrfs_add_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *tree_root, - u64 root_id, u8 type, u64 ref_id, - u64 dirid, u64 sequence, + u64 root_id, u64 ref_id, u64 dirid, u64 sequence, + const char *name, int name_len); +int btrfs_del_root_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *tree_root, + u64 root_id, u64 ref_id, u64 dirid, u64 *sequence, const char *name, int name_len); int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_key *key); @@ -2149,6 +2160,10 @@ btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans, struct btrfs_path *path, u64 dir, u64 objectid, const char *name, int name_len, int mod); +struct btrfs_dir_item * +btrfs_search_dir_index_item(struct btrfs_root *root, + struct btrfs_path *path, u64 dirid, + const char *name, int name_len); struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root, struct btrfs_path *path, const char *name, int name_len); @@ -2171,6 +2186,7 @@ int btrfs_insert_orphan_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 offset); int btrfs_del_orphan_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 offset); +int btrfs_find_orphan_item(struct btrfs_root *root, u64 offset); /* inode-map.c */ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans, @@ -2243,6 +2259,10 @@ int btrfs_unlink_inode(struct btrfs_trans_handle *trans, int btrfs_add_link(struct btrfs_trans_handle *trans, struct inode *parent_inode, struct inode *inode, const char *name, int name_len, int add_backref, u64 index); +int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct inode *dir, u64 objectid, + const char *name, int name_len); int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 new_size, diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c index 1d70236ba00..f3a6075519c 100644 --- a/fs/btrfs/dir-item.c +++ b/fs/btrfs/dir-item.c @@ -281,6 +281,53 @@ btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans, return btrfs_match_dir_item_name(root, path, name, name_len); } +struct btrfs_dir_item * +btrfs_search_dir_index_item(struct btrfs_root *root, + struct btrfs_path *path, u64 dirid, + const char *name, int name_len) +{ + struct extent_buffer *leaf; + struct btrfs_dir_item *di; + struct btrfs_key key; + u32 nritems; + int ret; + + key.objectid = dirid; + key.type = BTRFS_DIR_INDEX_KEY; + key.offset = 0; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + return ERR_PTR(ret); + + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + + while (1) { + if (path->slots[0] >= nritems) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) + return ERR_PTR(ret); + if (ret > 0) + break; + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + continue; + } + + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY) + break; + + di = btrfs_match_dir_item_name(root, path, name, name_len); + if (di) + return di; + + path->slots[0]++; + } + return NULL; +} + struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 dir, diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 790f4b61a3d..a4f531047c4 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -41,6 +41,7 @@ static struct extent_io_ops btree_extent_io_ops; static void end_workqueue_fn(struct btrfs_work *work); +static void free_fs_root(struct btrfs_root *root); static atomic_t btrfs_bdi_num = ATOMIC_INIT(0); @@ -951,14 +952,16 @@ static int find_and_setup_root(struct btrfs_root *tree_root, root, fs_info, objectid); ret = btrfs_find_last_root(tree_root, objectid, &root->root_item, &root->root_key); + if (ret > 0) + return -ENOENT; BUG_ON(ret); generation = btrfs_root_generation(&root->root_item); blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item)); root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item), blocksize, generation); - root->commit_root = btrfs_root_node(root); BUG_ON(!root->node); + root->commit_root = btrfs_root_node(root); return 0; } @@ -1176,39 +1179,66 @@ struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info, return fs_info->dev_root; if (location->objectid == BTRFS_CSUM_TREE_OBJECTID) return fs_info->csum_root; - +again: + spin_lock(&fs_info->fs_roots_radix_lock); root = radix_tree_lookup(&fs_info->fs_roots_radix, (unsigned long)location->objectid); + spin_unlock(&fs_info->fs_roots_radix_lock); if (root) return root; + ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid); + if (ret == 0) + ret = -ENOENT; + if (ret < 0) + return ERR_PTR(ret); + root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location); if (IS_ERR(root)) return root; + WARN_ON(btrfs_root_refs(&root->root_item) == 0); set_anon_super(&root->anon_super, NULL); + ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM); + if (ret) + goto fail; + + spin_lock(&fs_info->fs_roots_radix_lock); ret = radix_tree_insert(&fs_info->fs_roots_radix, (unsigned long)root->root_key.objectid, root); + if (ret == 0) + root->in_radix = 1; + spin_unlock(&fs_info->fs_roots_radix_lock); + radix_tree_preload_end(); if (ret) { - free_extent_buffer(root->node); - kfree(root); - return ERR_PTR(ret); + if (ret == -EEXIST) { + free_fs_root(root); + goto again; + } + goto fail; } - if (!(fs_info->sb->s_flags & MS_RDONLY)) { - ret = btrfs_find_dead_roots(fs_info->tree_root, - root->root_key.objectid); - BUG_ON(ret); + + ret = btrfs_find_dead_roots(fs_info->tree_root, + root->root_key.objectid); + WARN_ON(ret); + + if (!(fs_info->sb->s_flags & MS_RDONLY)) btrfs_orphan_cleanup(root); - } + return root; +fail: + free_fs_root(root); + return ERR_PTR(ret); } struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_key *location, const char *name, int namelen) { + return btrfs_read_fs_root_no_name(fs_info, location); +#if 0 struct btrfs_root *root; int ret; @@ -1225,7 +1255,7 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info, kfree(root); return ERR_PTR(ret); } -#if 0 + ret = btrfs_sysfs_add_root(root); if (ret) { free_extent_buffer(root->node); @@ -1233,9 +1263,9 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info, kfree(root); return ERR_PTR(ret); } -#endif root->in_sysfs = 1; return root; +#endif } static int btrfs_congested_fn(void *congested_data, int bdi_bits) @@ -2229,20 +2259,25 @@ int write_ctree_super(struct btrfs_trans_handle *trans, int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root) { - WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree)); + spin_lock(&fs_info->fs_roots_radix_lock); radix_tree_delete(&fs_info->fs_roots_radix, (unsigned long)root->root_key.objectid); + spin_unlock(&fs_info->fs_roots_radix_lock); + free_fs_root(root); + return 0; +} + +static void free_fs_root(struct btrfs_root *root) +{ + WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree)); if (root->anon_super.s_dev) { down_write(&root->anon_super.s_umount); kill_anon_super(&root->anon_super); } - if (root->node) - free_extent_buffer(root->node); - if (root->commit_root) - free_extent_buffer(root->commit_root); + free_extent_buffer(root->node); + free_extent_buffer(root->commit_root); kfree(root->name); kfree(root); - return 0; } static int del_fs_roots(struct btrfs_fs_info *fs_info) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 9e81f3184f2..6036b36789c 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2373,6 +2373,69 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry) return ret; } +int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct inode *dir, u64 objectid, + const char *name, int name_len) +{ + struct btrfs_path *path; + struct extent_buffer *leaf; + struct btrfs_dir_item *di; + struct btrfs_key key; + u64 index; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino, + name, name_len, -1); + BUG_ON(!di || IS_ERR(di)); + + leaf = path->nodes[0]; + btrfs_dir_item_key_to_cpu(leaf, di, &key); + WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); + ret = btrfs_delete_one_dir_name(trans, root, path, di); + BUG_ON(ret); + btrfs_release_path(root, path); + + ret = btrfs_del_root_ref(trans, root->fs_info->tree_root, + objectid, root->root_key.objectid, + dir->i_ino, &index, name, name_len); + if (ret < 0) { + BUG_ON(ret != -ENOENT); + di = btrfs_search_dir_index_item(root, path, dir->i_ino, + name, name_len); + BUG_ON(!di || IS_ERR(di)); + + leaf = path->nodes[0]; + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + btrfs_release_path(root, path); + index = key.offset; + } + + di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino, + index, name, name_len, -1); + BUG_ON(!di || IS_ERR(di)); + + leaf = path->nodes[0]; + btrfs_dir_item_key_to_cpu(leaf, di, &key); + WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); + ret = btrfs_delete_one_dir_name(trans, root, path, di); + BUG_ON(ret); + btrfs_release_path(root, path); + + btrfs_i_size_write(dir, dir->i_size - name_len * 2); + dir->i_mtime = dir->i_ctime = CURRENT_TIME; + ret = btrfs_update_inode(trans, root, dir); + BUG_ON(ret); + dir->i_sb->s_dirt = 1; + + btrfs_free_path(path); + return 0; +} + static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) { struct inode *inode = dentry->d_inode; @@ -2382,29 +2445,31 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) struct btrfs_trans_handle *trans; unsigned long nr = 0; - /* - * the FIRST_FREE_OBJECTID check makes sure we don't try to rmdir - * the root of a subvolume or snapshot - */ if (inode->i_size > BTRFS_EMPTY_DIR_SIZE || - inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) { + inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) return -ENOTEMPTY; - } trans = btrfs_start_transaction(root, 1); btrfs_set_trans_block_group(trans, dir); + if (unlikely(inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { + err = btrfs_unlink_subvol(trans, root, dir, + BTRFS_I(inode)->location.objectid, + dentry->d_name.name, + dentry->d_name.len); + goto out; + } + err = btrfs_orphan_add(trans, inode); if (err) - goto fail_trans; + goto out; /* now the directory is empty */ err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode, dentry->d_name.name, dentry->d_name.len); if (!err) btrfs_i_size_write(inode, 0); - -fail_trans: +out: nr = trans->blocks_used; ret = btrfs_end_transaction_throttle(trans, root); btrfs_btree_balance_dirty(root, nr); @@ -3091,29 +3156,67 @@ out_err: * is kind of like crossing a mount point. */ static int fixup_tree_root_location(struct btrfs_root *root, - struct btrfs_key *location, - struct btrfs_root **sub_root, - struct dentry *dentry) + struct inode *dir, + struct dentry *dentry, + struct btrfs_key *location, + struct btrfs_root **sub_root) { - struct btrfs_root_item *ri; + struct btrfs_path *path; + struct btrfs_root *new_root; + struct btrfs_root_ref *ref; + struct extent_buffer *leaf; + int ret; + int err = 0; - if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY) - return 0; - if (location->objectid == BTRFS_ROOT_TREE_OBJECTID) - return 0; + path = btrfs_alloc_path(); + if (!path) { + err = -ENOMEM; + goto out; + } - *sub_root = btrfs_read_fs_root(root->fs_info, location, - dentry->d_name.name, - dentry->d_name.len); - if (IS_ERR(*sub_root)) - return PTR_ERR(*sub_root); + err = -ENOENT; + ret = btrfs_find_root_ref(root->fs_info->tree_root, path, + BTRFS_I(dir)->root->root_key.objectid, + location->objectid); + if (ret) { + if (ret < 0) + err = ret; + goto out; + } - ri = &(*sub_root)->root_item; - location->objectid = btrfs_root_dirid(ri); - btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY); - location->offset = 0; + leaf = path->nodes[0]; + ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); + if (btrfs_root_ref_dirid(leaf, ref) != dir->i_ino || + btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len) + goto out; - return 0; + ret = memcmp_extent_buffer(leaf, dentry->d_name.name, + (unsigned long)(ref + 1), + dentry->d_name.len); + if (ret) + goto out; + + btrfs_release_path(root->fs_info->tree_root, path); + + new_root = btrfs_read_fs_root_no_name(root->fs_info, location); + if (IS_ERR(new_root)) { + err = PTR_ERR(new_root); + goto out; + } + + if (btrfs_root_refs(&new_root->root_item) == 0) { + err = -ENOENT; + goto out; + } + + *sub_root = new_root; + location->objectid = btrfs_root_dirid(&new_root->root_item); + location->type = BTRFS_INODE_ITEM_KEY; + location->offset = 0; + err = 0; +out: + btrfs_free_path(path); + return err; } static void inode_tree_add(struct inode *inode) @@ -3246,11 +3349,34 @@ struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, return inode; } +static struct inode *new_simple_dir(struct super_block *s, + struct btrfs_key *key, + struct btrfs_root *root) +{ + struct inode *inode = new_inode(s); + + if (!inode) + return ERR_PTR(-ENOMEM); + + init_btrfs_i(inode); + + BTRFS_I(inode)->root = root; + memcpy(&BTRFS_I(inode)->location, key, sizeof(*key)); + BTRFS_I(inode)->dummy_inode = 1; + + inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID; + inode->i_op = &simple_dir_inode_operations; + inode->i_fop = &simple_dir_operations; + inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO; + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; + + return inode; +} + struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) { struct inode *inode; - struct btrfs_inode *bi = BTRFS_I(dir); - struct btrfs_root *root = bi->root; + struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_root *sub_root = root; struct btrfs_key location; int ret; @@ -3263,17 +3389,25 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) if (ret < 0) return ERR_PTR(ret); - inode = NULL; - if (location.objectid) { - ret = fixup_tree_root_location(root, &location, &sub_root, - dentry); - if (ret < 0) - return ERR_PTR(ret); - if (ret > 0) - return ERR_PTR(-ENOENT); + if (location.objectid == 0) + return NULL; + + if (location.type == BTRFS_INODE_ITEM_KEY) { + inode = btrfs_iget(dir->i_sb, &location, root); + return inode; + } + + BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); + + ret = fixup_tree_root_location(root, dir, dentry, + &location, &sub_root); + if (ret < 0) { + if (ret != -ENOENT) + inode = ERR_PTR(ret); + else + inode = new_simple_dir(dir->i_sb, &location, sub_root); + } else { inode = btrfs_iget(dir->i_sb, &location, sub_root); - if (IS_ERR(inode)) - return ERR_CAST(inode); } return inode; } @@ -3283,9 +3417,6 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, { struct inode *inode; - if (dentry->d_name.len > BTRFS_NAME_LEN) - return ERR_PTR(-ENAMETOOLONG); - inode = btrfs_lookup_dentry(dir, dentry); if (IS_ERR(inode)) return ERR_CAST(inode); @@ -3691,26 +3822,35 @@ int btrfs_add_link(struct btrfs_trans_handle *trans, struct inode *parent_inode, struct inode *inode, const char *name, int name_len, int add_backref, u64 index) { - int ret; + int ret = 0; struct btrfs_key key; struct btrfs_root *root = BTRFS_I(parent_inode)->root; - key.objectid = inode->i_ino; - btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); - key.offset = 0; + if (unlikely(inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) { + memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key)); + } else { + key.objectid = inode->i_ino; + btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); + key.offset = 0; + } + + if (unlikely(inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) { + ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, + key.objectid, root->root_key.objectid, + parent_inode->i_ino, + index, name, name_len); + } else if (add_backref) { + ret = btrfs_insert_inode_ref(trans, root, + name, name_len, inode->i_ino, + parent_inode->i_ino, index); + } - ret = btrfs_insert_dir_item(trans, root, name, name_len, - parent_inode->i_ino, - &key, btrfs_inode_type(inode), - index); if (ret == 0) { - if (add_backref) { - ret = btrfs_insert_inode_ref(trans, root, - name, name_len, - inode->i_ino, - parent_inode->i_ino, - index); - } + ret = btrfs_insert_dir_item(trans, root, name, name_len, + parent_inode->i_ino, &key, + btrfs_inode_type(inode), index); + BUG_ON(ret); + btrfs_i_size_write(parent_inode, parent_inode->i_size + name_len * 2); parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME; @@ -4800,31 +4940,29 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, { struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(old_dir)->root; + struct btrfs_root *dest = BTRFS_I(new_dir)->root; struct inode *new_inode = new_dentry->d_inode; struct inode *old_inode = old_dentry->d_inode; struct timespec ctime = CURRENT_TIME; u64 index = 0; + u64 root_objectid; int ret; - /* we're not allowed to rename between subvolumes */ - if (BTRFS_I(old_inode)->root->root_key.objectid != - BTRFS_I(new_dir)->root->root_key.objectid) + /* we only allow rename subvolume link between subvolumes */ + if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) return -EXDEV; - if (S_ISDIR(old_inode->i_mode) && new_inode && - new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) { + if (old_inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID || + (new_inode && new_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) return -ENOTEMPTY; - } - /* to rename a snapshot or subvolume, we need to juggle the - * backrefs. This isn't coded yet - */ - if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) - return -EXDEV; + if (S_ISDIR(old_inode->i_mode) && new_inode && + new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) + return -ENOTEMPTY; ret = btrfs_check_metadata_free_space(root); if (ret) - goto out_unlock; + return ret; /* * we're using rename to replace one file with another. @@ -4837,6 +4975,9 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, trans = btrfs_start_transaction(root, 1); + if (dest != root) + btrfs_record_root_in_trans(trans, dest); + /* * make sure the inode gets flushed if it is replacing * something. @@ -4846,18 +4987,22 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, btrfs_add_ordered_operation(trans, root, old_inode); } - /* - * this is an ugly little race, but the rename is required to make - * sure that if we crash, the inode is either at the old name - * or the new one. pinning the log transaction lets us make sure - * we don't allow a log commit to come in after we unlink the - * name but before we add the new name back in. - */ - btrfs_pin_log_trans(root); + if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) { + /* force full log commit if subvolume involved. */ + root->fs_info->last_trans_log_full_commit = trans->transid; + } else { + /* + * this is an ugly little race, but the rename is required + * to make sure that if we crash, the inode is either at the + * old name or the new one. pinning the log transaction lets + * us make sure we don't allow a log commit to come in after + * we unlink the name but before we add the new name back in. + */ + btrfs_pin_log_trans(root); + } btrfs_set_trans_block_group(trans, new_dir); - btrfs_inc_nlink(old_dentry->d_inode); old_dir->i_ctime = old_dir->i_mtime = ctime; new_dir->i_ctime = new_dir->i_mtime = ctime; old_inode->i_ctime = ctime; @@ -4865,47 +5010,58 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, if (old_dentry->d_parent != new_dentry->d_parent) btrfs_record_unlink_dir(trans, old_dir, old_inode, 1); - ret = btrfs_unlink_inode(trans, root, old_dir, old_dentry->d_inode, - old_dentry->d_name.name, - old_dentry->d_name.len); - if (ret) - goto out_fail; + if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) { + root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; + ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid, + old_dentry->d_name.name, + old_dentry->d_name.len); + } else { + btrfs_inc_nlink(old_dentry->d_inode); + ret = btrfs_unlink_inode(trans, root, old_dir, + old_dentry->d_inode, + old_dentry->d_name.name, + old_dentry->d_name.len); + } + BUG_ON(ret); if (new_inode) { new_inode->i_ctime = CURRENT_TIME; - ret = btrfs_unlink_inode(trans, root, new_dir, - new_dentry->d_inode, - new_dentry->d_name.name, - new_dentry->d_name.len); - if (ret) - goto out_fail; + if (unlikely(new_inode->i_ino == + BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { + root_objectid = BTRFS_I(new_inode)->location.objectid; + ret = btrfs_unlink_subvol(trans, dest, new_dir, + root_objectid, + new_dentry->d_name.name, + new_dentry->d_name.len); + BUG_ON(new_inode->i_nlink == 0); + } else { + ret = btrfs_unlink_inode(trans, dest, new_dir, + new_dentry->d_inode, + new_dentry->d_name.name, + new_dentry->d_name.len); + } + BUG_ON(ret); if (new_inode->i_nlink == 0) { ret = btrfs_orphan_add(trans, new_dentry->d_inode); - if (ret) - goto out_fail; + BUG_ON(ret); } - } ret = btrfs_set_inode_index(new_dir, &index); - if (ret) - goto out_fail; + BUG_ON(ret); - ret = btrfs_add_link(trans, new_dentry->d_parent->d_inode, - old_inode, new_dentry->d_name.name, + ret = btrfs_add_link(trans, new_dir, old_inode, + new_dentry->d_name.name, new_dentry->d_name.len, 1, index); - if (ret) - goto out_fail; + BUG_ON(ret); - btrfs_log_new_name(trans, old_inode, old_dir, - new_dentry->d_parent); -out_fail: + if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) { + btrfs_log_new_name(trans, old_inode, old_dir, + new_dentry->d_parent); + btrfs_end_log_trans(root); + } - /* this btrfs_end_log_trans just allows the current - * log-sub transaction to complete - */ - btrfs_end_log_trans(root); btrfs_end_transaction_throttle(trans, root); -out_unlock: + return ret; } diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index ef0188fb3cc..9b3a88755e5 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -322,20 +322,9 @@ static noinline int create_subvol(struct btrfs_root *root, ret = btrfs_update_inode(trans, root, dir); BUG_ON(ret); - /* add the backref first */ ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, - objectid, BTRFS_ROOT_BACKREF_KEY, - root->root_key.objectid, + objectid, root->root_key.objectid, dir->i_ino, index, name, namelen); - - BUG_ON(ret); - - /* now add the forward ref */ - ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, - root->root_key.objectid, BTRFS_ROOT_REF_KEY, - objectid, - dir->i_ino, index, name, namelen); - BUG_ON(ret); ret = btrfs_commit_transaction(trans, root); diff --git a/fs/btrfs/orphan.c b/fs/btrfs/orphan.c index 3c0d52af4f8..79cba5fbc28 100644 --- a/fs/btrfs/orphan.c +++ b/fs/btrfs/orphan.c @@ -65,3 +65,23 @@ out: btrfs_free_path(path); return ret; } + +int btrfs_find_orphan_item(struct btrfs_root *root, u64 offset) +{ + struct btrfs_path *path; + struct btrfs_key key; + int ret; + + key.objectid = BTRFS_ORPHAN_OBJECTID; + key.type = BTRFS_ORPHAN_ITEM_KEY; + key.offset = offset; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + + btrfs_free_path(path); + return ret; +} diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c index 0ddc6d61c55..5ef72599a58 100644 --- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -278,31 +278,57 @@ out: return ret; } -#if 0 /* this will get used when snapshot deletion is implemented */ int btrfs_del_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *tree_root, - u64 root_id, u8 type, u64 ref_id) + u64 root_id, u64 ref_id, u64 dirid, u64 *sequence, + const char *name, int name_len) + { + struct btrfs_path *path; + struct btrfs_root_ref *ref; + struct extent_buffer *leaf; struct btrfs_key key; + unsigned long ptr; + int err = 0; int ret; - struct btrfs_path *path; path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; key.objectid = root_id; - key.type = type; + key.type = BTRFS_ROOT_BACKREF_KEY; key.offset = ref_id; - +again: ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1); - BUG_ON(ret); - - ret = btrfs_del_item(trans, tree_root, path); - BUG_ON(ret); + BUG_ON(ret < 0); + if (ret == 0) { + leaf = path->nodes[0]; + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_root_ref); + + WARN_ON(btrfs_root_ref_dirid(leaf, ref) != dirid); + WARN_ON(btrfs_root_ref_name_len(leaf, ref) != name_len); + ptr = (unsigned long)(ref + 1); + WARN_ON(memcmp_extent_buffer(leaf, name, ptr, name_len)); + *sequence = btrfs_root_ref_sequence(leaf, ref); + + ret = btrfs_del_item(trans, tree_root, path); + BUG_ON(ret); + } else + err = -ENOENT; + + if (key.type == BTRFS_ROOT_BACKREF_KEY) { + btrfs_release_path(tree_root, path); + key.objectid = ref_id; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = root_id; + goto again; + } btrfs_free_path(path); - return ret; + return err; } -#endif int btrfs_find_root_ref(struct btrfs_root *tree_root, struct btrfs_path *path, @@ -319,7 +345,6 @@ int btrfs_find_root_ref(struct btrfs_root *tree_root, return ret; } - /* * add a btrfs_root_ref item. type is either BTRFS_ROOT_REF_KEY * or BTRFS_ROOT_BACKREF_KEY. @@ -335,8 +360,7 @@ int btrfs_find_root_ref(struct btrfs_root *tree_root, */ int btrfs_add_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *tree_root, - u64 root_id, u8 type, u64 ref_id, - u64 dirid, u64 sequence, + u64 root_id, u64 ref_id, u64 dirid, u64 sequence, const char *name, int name_len) { struct btrfs_key key; @@ -346,13 +370,14 @@ int btrfs_add_root_ref(struct btrfs_trans_handle *trans, struct extent_buffer *leaf; unsigned long ptr; - path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; key.objectid = root_id; - key.type = type; + key.type = BTRFS_ROOT_BACKREF_KEY; key.offset = ref_id; - +again: ret = btrfs_insert_empty_item(trans, tree_root, path, &key, sizeof(*ref) + name_len); BUG_ON(ret); @@ -366,6 +391,14 @@ int btrfs_add_root_ref(struct btrfs_trans_handle *trans, write_extent_buffer(leaf, name, ptr, name_len); btrfs_mark_buffer_dirty(leaf); + if (key.type == BTRFS_ROOT_BACKREF_KEY) { + btrfs_release_path(tree_root, path); + key.objectid = ref_id; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = root_id; + goto again; + } + btrfs_free_path(path); - return ret; + return 0; } diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 94f816cb6e3..915077725fe 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -779,24 +779,14 @@ static noinline int finish_pending_snapshot(struct btrfs_fs_info *fs_info, ret = btrfs_update_inode(trans, parent_root, parent_inode); BUG_ON(ret); - /* add the backref first */ ret = btrfs_add_root_ref(trans, parent_root->fs_info->tree_root, pending->root_key.objectid, - BTRFS_ROOT_BACKREF_KEY, parent_root->root_key.objectid, parent_inode->i_ino, index, pending->name, namelen); BUG_ON(ret); - /* now add the forward ref */ - ret = btrfs_add_root_ref(trans, parent_root->fs_info->tree_root, - parent_root->root_key.objectid, - BTRFS_ROOT_REF_KEY, - pending->root_key.objectid, - parent_inode->i_ino, index, pending->name, - namelen); - inode = btrfs_lookup_dentry(parent_inode, pending->dentry); d_instantiate(pending->dentry, inode); fail: -- cgit v1.2.3-70-g09d2 From 76dda93c6ae2c1dc3e6cde34569d6aca26b0c918 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Mon, 21 Sep 2009 16:00:26 -0400 Subject: Btrfs: add snapshot/subvolume destroy ioctl This patch adds snapshot/subvolume destroy ioctl. A subvolume that isn't being used and doesn't contains links to other subvolumes can be destroyed. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 12 +- fs/btrfs/disk-io.c | 81 ++++++++++--- fs/btrfs/export.c | 133 ++++++++++++-------- fs/btrfs/extent-tree.c | 21 +++- fs/btrfs/inode.c | 134 +++++++++++++++++++-- fs/btrfs/ioctl.c | 320 ++++++++++++++++++++++++++++--------------------- fs/btrfs/ioctl.h | 3 +- fs/btrfs/relocation.c | 41 ++++++- fs/btrfs/root-tree.c | 69 ++++++++++- fs/btrfs/super.c | 1 + fs/btrfs/transaction.c | 10 +- fs/btrfs/tree-log.c | 13 +- 12 files changed, 605 insertions(+), 233 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 6ade48b227e..bc57e236ac6 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -839,9 +839,7 @@ struct btrfs_fs_info { struct mutex transaction_kthread_mutex; struct mutex cleaner_mutex; struct mutex chunk_mutex; - struct mutex drop_mutex; struct mutex volume_mutex; - struct mutex tree_reloc_mutex; /* * this protects the ordered operations list only while we are * processing all of the entries on it. This way we make @@ -852,6 +850,10 @@ struct btrfs_fs_info { struct mutex ordered_operations_mutex; struct rw_semaphore extent_commit_sem; + struct rw_semaphore subvol_sem; + + struct srcu_struct subvol_srcu; + struct list_head trans_list; struct list_head hashers; struct list_head dead_roots; @@ -2142,6 +2144,7 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct int btrfs_search_root(struct btrfs_root *root, u64 search_start, u64 *found_objectid); int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid); +int btrfs_find_orphan_roots(struct btrfs_root *tree_root); int btrfs_set_root_node(struct btrfs_root_item *item, struct extent_buffer *node); /* dir-item.c */ @@ -2273,7 +2276,7 @@ int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end); int btrfs_writepages(struct address_space *mapping, struct writeback_control *wbc); int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, - struct btrfs_root *new_root, struct dentry *dentry, + struct btrfs_root *new_root, u64 new_dirid, u64 alloc_hint); int btrfs_merge_bio_hook(struct page *page, unsigned long offset, size_t size, struct bio *bio, unsigned long bio_flags); @@ -2289,6 +2292,7 @@ int btrfs_write_inode(struct inode *inode, int wait); void btrfs_dirty_inode(struct inode *inode); struct inode *btrfs_alloc_inode(struct super_block *sb); void btrfs_destroy_inode(struct inode *inode); +void btrfs_drop_inode(struct inode *inode); int btrfs_init_cachep(void); void btrfs_destroy_cachep(void); long btrfs_ioctl_trans_end(struct file *file); @@ -2306,6 +2310,8 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode); int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode); void btrfs_orphan_cleanup(struct btrfs_root *root); int btrfs_cont_expand(struct inode *inode, loff_t size); +int btrfs_invalidate_inodes(struct btrfs_root *root); +extern struct dentry_operations btrfs_dentry_operations; /* ioctl.c */ long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg); diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index a4f531047c4..a0d41e713f3 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1378,8 +1378,10 @@ static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi) err = bdi_register(bdi, NULL, "btrfs-%d", atomic_inc_return(&btrfs_bdi_num)); - if (err) + if (err) { + bdi_destroy(bdi); return err; + } bdi->ra_pages = default_backing_dev_info.ra_pages; bdi->unplug_io_fn = btrfs_unplug_io_fn; @@ -1469,9 +1471,12 @@ static int cleaner_kthread(void *arg) break; vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE); - mutex_lock(&root->fs_info->cleaner_mutex); - btrfs_clean_old_snapshots(root); - mutex_unlock(&root->fs_info->cleaner_mutex); + + if (!(root->fs_info->sb->s_flags & MS_RDONLY) && + mutex_trylock(&root->fs_info->cleaner_mutex)) { + btrfs_clean_old_snapshots(root); + mutex_unlock(&root->fs_info->cleaner_mutex); + } if (freezing(current)) { refrigerator(); @@ -1576,7 +1581,26 @@ struct btrfs_root *open_ctree(struct super_block *sb, err = -ENOMEM; goto fail; } - INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS); + + ret = init_srcu_struct(&fs_info->subvol_srcu); + if (ret) { + err = ret; + goto fail; + } + + ret = setup_bdi(fs_info, &fs_info->bdi); + if (ret) { + err = ret; + goto fail_srcu; + } + + fs_info->btree_inode = new_inode(sb); + if (!fs_info->btree_inode) { + err = -ENOMEM; + goto fail_bdi; + } + + INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC); INIT_LIST_HEAD(&fs_info->trans_list); INIT_LIST_HEAD(&fs_info->dead_roots); INIT_LIST_HEAD(&fs_info->hashers); @@ -1586,6 +1610,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, spin_lock_init(&fs_info->delalloc_lock); spin_lock_init(&fs_info->new_trans_lock); spin_lock_init(&fs_info->ref_cache_lock); + spin_lock_init(&fs_info->fs_roots_radix_lock); init_completion(&fs_info->kobj_unregister); fs_info->tree_root = tree_root; @@ -1604,11 +1629,6 @@ struct btrfs_root *open_ctree(struct super_block *sb, fs_info->sb = sb; fs_info->max_extent = (u64)-1; fs_info->max_inline = 8192 * 1024; - if (setup_bdi(fs_info, &fs_info->bdi)) - goto fail_bdi; - fs_info->btree_inode = new_inode(sb); - fs_info->btree_inode->i_ino = 1; - fs_info->btree_inode->i_nlink = 1; fs_info->metadata_ratio = 8; fs_info->thread_pool_size = min_t(unsigned long, @@ -1620,6 +1640,8 @@ struct btrfs_root *open_ctree(struct super_block *sb, sb->s_blocksize = 4096; sb->s_blocksize_bits = blksize_bits(4096); + fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID; + fs_info->btree_inode->i_nlink = 1; /* * we set the i_size on the btree inode to the max possible int. * the real end of the address space is determined by all of @@ -1638,6 +1660,11 @@ struct btrfs_root *open_ctree(struct super_block *sb, BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops; + BTRFS_I(fs_info->btree_inode)->root = tree_root; + memset(&BTRFS_I(fs_info->btree_inode)->location, 0, + sizeof(struct btrfs_key)); + BTRFS_I(fs_info->btree_inode)->dummy_inode = 1; + spin_lock_init(&fs_info->block_group_cache_lock); fs_info->block_group_cache_tree.rb_node = NULL; @@ -1648,21 +1675,16 @@ struct btrfs_root *open_ctree(struct super_block *sb, fs_info->pinned_extents = &fs_info->freed_extents[0]; fs_info->do_barriers = 1; - BTRFS_I(fs_info->btree_inode)->root = tree_root; - memset(&BTRFS_I(fs_info->btree_inode)->location, 0, - sizeof(struct btrfs_key)); - insert_inode_hash(fs_info->btree_inode); mutex_init(&fs_info->trans_mutex); mutex_init(&fs_info->ordered_operations_mutex); mutex_init(&fs_info->tree_log_mutex); - mutex_init(&fs_info->drop_mutex); mutex_init(&fs_info->chunk_mutex); mutex_init(&fs_info->transaction_kthread_mutex); mutex_init(&fs_info->cleaner_mutex); mutex_init(&fs_info->volume_mutex); - mutex_init(&fs_info->tree_reloc_mutex); init_rwsem(&fs_info->extent_commit_sem); + init_rwsem(&fs_info->subvol_sem); btrfs_init_free_cluster(&fs_info->meta_alloc_cluster); btrfs_init_free_cluster(&fs_info->data_alloc_cluster); @@ -1941,6 +1963,9 @@ printk("thread pool is %d\n", fs_info->thread_pool_size); } } + ret = btrfs_find_orphan_roots(tree_root); + BUG_ON(ret); + if (!(sb->s_flags & MS_RDONLY)) { ret = btrfs_recover_relocation(tree_root); BUG_ON(ret); @@ -2000,6 +2025,8 @@ fail_iput: btrfs_mapping_tree_free(&fs_info->mapping_tree); fail_bdi: bdi_destroy(&fs_info->bdi); +fail_srcu: + cleanup_srcu_struct(&fs_info->subvol_srcu); fail: kfree(extent_root); kfree(tree_root); @@ -2263,6 +2290,10 @@ int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root) radix_tree_delete(&fs_info->fs_roots_radix, (unsigned long)root->root_key.objectid); spin_unlock(&fs_info->fs_roots_radix_lock); + + if (btrfs_root_refs(&root->root_item) == 0) + synchronize_srcu(&fs_info->subvol_srcu); + free_fs_root(root); return 0; } @@ -2286,6 +2317,20 @@ static int del_fs_roots(struct btrfs_fs_info *fs_info) struct btrfs_root *gang[8]; int i; + while (!list_empty(&fs_info->dead_roots)) { + gang[0] = list_entry(fs_info->dead_roots.next, + struct btrfs_root, root_list); + list_del(&gang[0]->root_list); + + if (gang[0]->in_radix) { + btrfs_free_fs_root(fs_info, gang[0]); + } else { + free_extent_buffer(gang[0]->node); + free_extent_buffer(gang[0]->commit_root); + kfree(gang[0]); + } + } + while (1) { ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix, (void **)gang, 0, @@ -2315,9 +2360,6 @@ int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info) root_objectid = gang[ret - 1]->root_key.objectid + 1; for (i = 0; i < ret; i++) { root_objectid = gang[i]->root_key.objectid; - ret = btrfs_find_dead_roots(fs_info->tree_root, - root_objectid); - BUG_ON(ret); btrfs_orphan_cleanup(gang[i]); } root_objectid++; @@ -2405,6 +2447,7 @@ int close_ctree(struct btrfs_root *root) btrfs_mapping_tree_free(&fs_info->mapping_tree); bdi_destroy(&fs_info->bdi); + cleanup_srcu_struct(&fs_info->subvol_srcu); kfree(fs_info->extent_root); kfree(fs_info->tree_root); diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c index 9596b40caa4..ba5c3fd5ab8 100644 --- a/fs/btrfs/export.c +++ b/fs/btrfs/export.c @@ -28,7 +28,7 @@ static int btrfs_encode_fh(struct dentry *dentry, u32 *fh, int *max_len, len = BTRFS_FID_SIZE_NON_CONNECTABLE; type = FILEID_BTRFS_WITHOUT_PARENT; - fid->objectid = BTRFS_I(inode)->location.objectid; + fid->objectid = inode->i_ino; fid->root_objectid = BTRFS_I(inode)->root->objectid; fid->gen = inode->i_generation; @@ -60,34 +60,61 @@ static int btrfs_encode_fh(struct dentry *dentry, u32 *fh, int *max_len, } static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid, - u64 root_objectid, u32 generation) + u64 root_objectid, u32 generation, + int check_generation) { + struct btrfs_fs_info *fs_info = btrfs_sb(sb)->fs_info; struct btrfs_root *root; + struct dentry *dentry; struct inode *inode; struct btrfs_key key; + int index; + int err = 0; + + if (objectid < BTRFS_FIRST_FREE_OBJECTID) + return ERR_PTR(-ESTALE); key.objectid = root_objectid; btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); key.offset = (u64)-1; - root = btrfs_read_fs_root_no_name(btrfs_sb(sb)->fs_info, &key); - if (IS_ERR(root)) - return ERR_CAST(root); + index = srcu_read_lock(&fs_info->subvol_srcu); + + root = btrfs_read_fs_root_no_name(fs_info, &key); + if (IS_ERR(root)) { + err = PTR_ERR(root); + goto fail; + } + + if (btrfs_root_refs(&root->root_item) == 0) { + err = -ENOENT; + goto fail; + } key.objectid = objectid; btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); key.offset = 0; inode = btrfs_iget(sb, &key, root); - if (IS_ERR(inode)) - return (void *)inode; + if (IS_ERR(inode)) { + err = PTR_ERR(inode); + goto fail; + } + + srcu_read_unlock(&fs_info->subvol_srcu, index); - if (generation != inode->i_generation) { + if (check_generation && generation != inode->i_generation) { iput(inode); return ERR_PTR(-ESTALE); } - return d_obtain_alias(inode); + dentry = d_obtain_alias(inode); + if (!IS_ERR(dentry)) + dentry->d_op = &btrfs_dentry_operations; + return dentry; +fail: + srcu_read_unlock(&fs_info->subvol_srcu, index); + return ERR_PTR(err); } static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh, @@ -111,7 +138,7 @@ static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh, objectid = fid->parent_objectid; generation = fid->parent_gen; - return btrfs_get_dentry(sb, objectid, root_objectid, generation); + return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1); } static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh, @@ -133,66 +160,76 @@ static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh, root_objectid = fid->root_objectid; generation = fid->gen; - return btrfs_get_dentry(sb, objectid, root_objectid, generation); + return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1); } static struct dentry *btrfs_get_parent(struct dentry *child) { struct inode *dir = child->d_inode; + static struct dentry *dentry; struct btrfs_root *root = BTRFS_I(dir)->root; - struct btrfs_key key; struct btrfs_path *path; struct extent_buffer *leaf; - int slot; - u64 objectid; + struct btrfs_root_ref *ref; + struct btrfs_key key; + struct btrfs_key found_key; int ret; path = btrfs_alloc_path(); - key.objectid = dir->i_ino; - btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY); - key.offset = (u64)-1; + if (dir->i_ino == BTRFS_FIRST_FREE_OBJECTID) { + key.objectid = root->root_key.objectid; + key.type = BTRFS_ROOT_BACKREF_KEY; + key.offset = (u64)-1; + root = root->fs_info->tree_root; + } else { + key.objectid = dir->i_ino; + key.type = BTRFS_INODE_REF_KEY; + key.offset = (u64)-1; + } ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); - if (ret < 0) { - /* Error */ - btrfs_free_path(path); - return ERR_PTR(ret); + if (ret < 0) + goto fail; + + BUG_ON(ret == 0); + if (path->slots[0] == 0) { + ret = -ENOENT; + goto fail; } + + path->slots[0]--; leaf = path->nodes[0]; - slot = path->slots[0]; - if (ret) { - /* btrfs_search_slot() returns the slot where we'd want to - insert a backref for parent inode #0xFFFFFFFFFFFFFFFF. - The _real_ backref, telling us what the parent inode - _actually_ is, will be in the slot _before_ the one - that btrfs_search_slot() returns. */ - if (!slot) { - /* Unless there is _no_ key in the tree before... */ - btrfs_free_path(path); - return ERR_PTR(-EIO); - } - slot--; + + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.objectid != key.objectid || found_key.type != key.type) { + ret = -ENOENT; + goto fail; } - btrfs_item_key_to_cpu(leaf, &key, slot); + if (found_key.type == BTRFS_ROOT_BACKREF_KEY) { + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_root_ref); + key.objectid = btrfs_root_ref_dirid(leaf, ref); + } else { + key.objectid = found_key.offset; + } btrfs_free_path(path); - if (key.objectid != dir->i_ino || key.type != BTRFS_INODE_REF_KEY) - return ERR_PTR(-EINVAL); - - objectid = key.offset; - - /* If we are already at the root of a subvol, return the real root */ - if (objectid == dir->i_ino) - return dget(dir->i_sb->s_root); + if (found_key.type == BTRFS_ROOT_BACKREF_KEY) { + return btrfs_get_dentry(root->fs_info->sb, key.objectid, + found_key.offset, 0, 0); + } - /* Build a new key for the inode item */ - key.objectid = objectid; - btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); + key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; - - return d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root)); + dentry = d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root)); + if (!IS_ERR(dentry)) + dentry->d_op = &btrfs_dentry_operations; + return dentry; +fail: + btrfs_free_path(path); + return ERR_PTR(ret); } const struct export_operations btrfs_export_ops = { diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 8fc92298218..4bd04f3fa8b 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -5463,9 +5463,24 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref) ret = btrfs_del_root(trans, tree_root, &root->root_key); BUG_ON(ret); - free_extent_buffer(root->node); - free_extent_buffer(root->commit_root); - kfree(root); + if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { + ret = btrfs_find_last_root(tree_root, root->root_key.objectid, + NULL, NULL); + BUG_ON(ret < 0); + if (ret > 0) { + ret = btrfs_del_orphan_item(trans, tree_root, + root->root_key.objectid); + BUG_ON(ret); + } + } + + if (root->in_radix) { + btrfs_free_fs_root(tree_root->fs_info, root); + } else { + free_extent_buffer(root->node); + free_extent_buffer(root->commit_root); + kfree(root); + } out: btrfs_end_transaction(trans, tree_root); kfree(wc); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 6036b36789c..db9cbd91eb4 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3089,6 +3089,11 @@ void btrfs_delete_inode(struct inode *inode) } btrfs_wait_ordered_range(inode, 0, (u64)-1); + if (inode->i_nlink > 0) { + BUG_ON(btrfs_root_refs(&root->root_item) != 0); + goto no_delete; + } + btrfs_i_size_write(inode, 0); trans = btrfs_join_transaction(root, 1); @@ -3225,11 +3230,13 @@ static void inode_tree_add(struct inode *inode) struct btrfs_inode *entry; struct rb_node **p; struct rb_node *parent; - again: p = &root->inode_tree.rb_node; parent = NULL; + if (hlist_unhashed(&inode->i_hash)) + return; + spin_lock(&root->inode_lock); while (*p) { parent = *p; @@ -3256,13 +3263,87 @@ again: static void inode_tree_del(struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; + int empty = 0; spin_lock(&root->inode_lock); if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree); RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); + empty = RB_EMPTY_ROOT(&root->inode_tree); } spin_unlock(&root->inode_lock); + + if (empty && btrfs_root_refs(&root->root_item) == 0) { + synchronize_srcu(&root->fs_info->subvol_srcu); + spin_lock(&root->inode_lock); + empty = RB_EMPTY_ROOT(&root->inode_tree); + spin_unlock(&root->inode_lock); + if (empty) + btrfs_add_dead_root(root); + } +} + +int btrfs_invalidate_inodes(struct btrfs_root *root) +{ + struct rb_node *node; + struct rb_node *prev; + struct btrfs_inode *entry; + struct inode *inode; + u64 objectid = 0; + + WARN_ON(btrfs_root_refs(&root->root_item) != 0); + + spin_lock(&root->inode_lock); +again: + node = root->inode_tree.rb_node; + prev = NULL; + while (node) { + prev = node; + entry = rb_entry(node, struct btrfs_inode, rb_node); + + if (objectid < entry->vfs_inode.i_ino) + node = node->rb_left; + else if (objectid > entry->vfs_inode.i_ino) + node = node->rb_right; + else + break; + } + if (!node) { + while (prev) { + entry = rb_entry(prev, struct btrfs_inode, rb_node); + if (objectid <= entry->vfs_inode.i_ino) { + node = prev; + break; + } + prev = rb_next(prev); + } + } + while (node) { + entry = rb_entry(node, struct btrfs_inode, rb_node); + objectid = entry->vfs_inode.i_ino + 1; + inode = igrab(&entry->vfs_inode); + if (inode) { + spin_unlock(&root->inode_lock); + if (atomic_read(&inode->i_count) > 1) + d_prune_aliases(inode); + /* + * btrfs_drop_inode will remove it from + * the inode cache when its usage count + * hits zero. + */ + iput(inode); + cond_resched(); + spin_lock(&root->inode_lock); + goto again; + } + + if (cond_resched_lock(&root->inode_lock)) + goto again; + + node = rb_next(node); + } + spin_unlock(&root->inode_lock); + return 0; } static noinline void init_btrfs_i(struct inode *inode) @@ -3379,8 +3460,11 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_root *sub_root = root; struct btrfs_key location; + int index; int ret; + dentry->d_op = &btrfs_dentry_operations; + if (dentry->d_name.len > BTRFS_NAME_LEN) return ERR_PTR(-ENAMETOOLONG); @@ -3399,6 +3483,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); + index = srcu_read_lock(&root->fs_info->subvol_srcu); ret = fixup_tree_root_location(root, dir, dentry, &location, &sub_root); if (ret < 0) { @@ -3409,9 +3494,24 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) } else { inode = btrfs_iget(dir->i_sb, &location, sub_root); } + srcu_read_unlock(&root->fs_info->subvol_srcu, index); + return inode; } +static int btrfs_dentry_delete(struct dentry *dentry) +{ + struct btrfs_root *root; + + if (!dentry->d_inode) + return 0; + + root = BTRFS_I(dentry->d_inode)->root; + if (btrfs_root_refs(&root->root_item) == 0) + return 1; + return 0; +} + static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) { @@ -4773,11 +4873,11 @@ out: * create a new subvolume directory/inode (helper for the ioctl). */ int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, - struct btrfs_root *new_root, struct dentry *dentry, + struct btrfs_root *new_root, u64 new_dirid, u64 alloc_hint) { struct inode *inode; - int error; + int err; u64 index = 0; inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid, @@ -4790,11 +4890,10 @@ int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, inode->i_nlink = 1; btrfs_i_size_write(inode, 0); - error = btrfs_update_inode(trans, new_root, inode); - if (error) - return error; + err = btrfs_update_inode(trans, new_root, inode); + BUG_ON(err); - d_instantiate(dentry, inode); + iput(inode); return 0; } @@ -4872,6 +4971,16 @@ void btrfs_destroy_inode(struct inode *inode) kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); } +void btrfs_drop_inode(struct inode *inode) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + + if (inode->i_nlink > 0 && btrfs_root_refs(&root->root_item) == 0) + generic_delete_inode(inode); + else + generic_drop_inode(inode); +} + static void init_once(void *foo) { struct btrfs_inode *ei = (struct btrfs_inode *) foo; @@ -4973,6 +5082,10 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT) filemap_flush(old_inode->i_mapping); + /* close the racy window with snapshot create/destroy ioctl */ + if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) + down_read(&root->fs_info->subvol_sem); + trans = btrfs_start_transaction(root, 1); if (dest != root) @@ -5062,6 +5175,8 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, btrfs_end_transaction_throttle(trans, root); + if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) + up_read(&root->fs_info->subvol_sem); return ret; } @@ -5420,6 +5535,7 @@ static struct inode_operations btrfs_dir_ro_inode_operations = { .lookup = btrfs_lookup, .permission = btrfs_permission, }; + static struct file_operations btrfs_dir_file_operations = { .llseek = generic_file_llseek, .read = generic_read_dir, @@ -5506,3 +5622,7 @@ static struct inode_operations btrfs_symlink_inode_operations = { .listxattr = btrfs_listxattr, .removexattr = btrfs_removexattr, }; + +struct dentry_operations btrfs_dentry_operations = { + .d_delete = btrfs_dentry_delete, +}; diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 9b3a88755e5..a13fd556db7 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -230,8 +230,8 @@ static noinline int create_subvol(struct btrfs_root *root, struct btrfs_root_item root_item; struct btrfs_inode_item *inode_item; struct extent_buffer *leaf; - struct btrfs_root *new_root = root; - struct inode *dir; + struct btrfs_root *new_root; + struct inode *dir = dentry->d_parent->d_inode; int ret; int err; u64 objectid; @@ -241,7 +241,7 @@ static noinline int create_subvol(struct btrfs_root *root, ret = btrfs_check_metadata_free_space(root); if (ret) - goto fail_commit; + return ret; trans = btrfs_start_transaction(root, 1); BUG_ON(!trans); @@ -304,11 +304,17 @@ static noinline int create_subvol(struct btrfs_root *root, if (ret) goto fail; + key.offset = (u64)-1; + new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); + BUG_ON(IS_ERR(new_root)); + + btrfs_record_root_in_trans(trans, new_root); + + ret = btrfs_create_subvol_root(trans, new_root, new_dirid, + BTRFS_I(dir)->block_group); /* * insert the directory item */ - key.offset = (u64)-1; - dir = dentry->d_parent->d_inode; ret = btrfs_set_inode_index(dir, &index); BUG_ON(ret); @@ -325,30 +331,15 @@ static noinline int create_subvol(struct btrfs_root *root, ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, objectid, root->root_key.objectid, dir->i_ino, index, name, namelen); - BUG_ON(ret); - ret = btrfs_commit_transaction(trans, root); - if (ret) - goto fail_commit; - - new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); - BUG_ON(!new_root); - - trans = btrfs_start_transaction(new_root, 1); - BUG_ON(!trans); - - ret = btrfs_create_subvol_root(trans, new_root, dentry, new_dirid, - BTRFS_I(dir)->block_group); - if (ret) - goto fail; + BUG_ON(ret); + d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry)); fail: nr = trans->blocks_used; - err = btrfs_commit_transaction(trans, new_root); + err = btrfs_commit_transaction(trans, root); if (err && !ret) ret = err; -fail_commit: - btrfs_btree_balance_dirty(root, nr); return ret; } @@ -409,14 +400,15 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child) * sys_mkdirat and vfs_mkdir, but we only do a single component lookup * inside this filesystem so it's quite a bit simpler. */ -static noinline int btrfs_mksubvol(struct path *parent, char *name, - int mode, int namelen, +static noinline int btrfs_mksubvol(struct path *parent, + char *name, int namelen, struct btrfs_root *snap_src) { + struct inode *dir = parent->dentry->d_inode; struct dentry *dentry; int error; - mutex_lock_nested(&parent->dentry->d_inode->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); dentry = lookup_one_len(name, parent->dentry, namelen); error = PTR_ERR(dentry); @@ -427,99 +419,39 @@ static noinline int btrfs_mksubvol(struct path *parent, char *name, if (dentry->d_inode) goto out_dput; - if (!IS_POSIXACL(parent->dentry->d_inode)) - mode &= ~current_umask(); - error = mnt_want_write(parent->mnt); if (error) goto out_dput; - error = btrfs_may_create(parent->dentry->d_inode, dentry); + error = btrfs_may_create(dir, dentry); if (error) goto out_drop_write; - /* - * Actually perform the low-level subvolume creation after all - * this VFS fuzz. - * - * Eventually we want to pass in an inode under which we create this - * subvolume, but for now all are under the filesystem root. - * - * Also we should pass on the mode eventually to allow creating new - * subvolume with specific mode bits. - */ + down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); + + if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) + goto out_up_read; + if (snap_src) { - struct dentry *dir = dentry->d_parent; - struct dentry *test = dir->d_parent; - struct btrfs_path *path = btrfs_alloc_path(); - int ret; - u64 test_oid; - u64 parent_oid = BTRFS_I(dir->d_inode)->root->root_key.objectid; - - test_oid = snap_src->root_key.objectid; - - ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, - path, parent_oid, test_oid); - if (ret == 0) - goto create; - btrfs_release_path(snap_src->fs_info->tree_root, path); - - /* we need to make sure we aren't creating a directory loop - * by taking a snapshot of something that has our current - * subvol in its directory tree. So, this loops through - * the dentries and checks the forward refs for each subvolume - * to see if is references the subvolume where we are - * placing this new snapshot. - */ - while (1) { - if (!test || - dir == snap_src->fs_info->sb->s_root || - test == snap_src->fs_info->sb->s_root || - test->d_inode->i_sb != snap_src->fs_info->sb) { - break; - } - if (S_ISLNK(test->d_inode->i_mode)) { - printk(KERN_INFO "Btrfs symlink in snapshot " - "path, failed\n"); - error = -EMLINK; - btrfs_free_path(path); - goto out_drop_write; - } - test_oid = - BTRFS_I(test->d_inode)->root->root_key.objectid; - ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, - path, test_oid, parent_oid); - if (ret == 0) { - printk(KERN_INFO "Btrfs snapshot creation " - "failed, looping\n"); - error = -EMLINK; - btrfs_free_path(path); - goto out_drop_write; - } - btrfs_release_path(snap_src->fs_info->tree_root, path); - test = test->d_parent; - } -create: - btrfs_free_path(path); - error = create_snapshot(snap_src, dentry, name, namelen); + error = create_snapshot(snap_src, dentry, + name, namelen); } else { - error = create_subvol(BTRFS_I(parent->dentry->d_inode)->root, - dentry, name, namelen); + error = create_subvol(BTRFS_I(dir)->root, dentry, + name, namelen); } - if (error) - goto out_drop_write; - - fsnotify_mkdir(parent->dentry->d_inode, dentry); + if (!error) + fsnotify_mkdir(dir, dentry); +out_up_read: + up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); out_drop_write: mnt_drop_write(parent->mnt); out_dput: dput(dentry); out_unlock: - mutex_unlock(&parent->dentry->d_inode->i_mutex); + mutex_unlock(&dir->i_mutex); return error; } - static int btrfs_defrag_file(struct file *file) { struct inode *inode = fdentry(file)->d_inode; @@ -597,7 +529,8 @@ out_unlock: return 0; } -static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg) +static noinline int btrfs_ioctl_resize(struct btrfs_root *root, + void __user *arg) { u64 new_size; u64 old_size; @@ -706,10 +639,7 @@ static noinline int btrfs_ioctl_snap_create(struct file *file, { struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; struct btrfs_ioctl_vol_args *vol_args; - struct btrfs_dir_item *di; - struct btrfs_path *path; struct file *src_file; - u64 root_dirid; int namelen; int ret = 0; @@ -727,32 +657,9 @@ static noinline int btrfs_ioctl_snap_create(struct file *file, goto out; } - path = btrfs_alloc_path(); - if (!path) { - ret = -ENOMEM; - goto out; - } - - root_dirid = root->fs_info->sb->s_root->d_inode->i_ino, - di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, - path, root_dirid, - vol_args->name, namelen, 0); - btrfs_free_path(path); - - if (di && !IS_ERR(di)) { - ret = -EEXIST; - goto out; - } - - if (IS_ERR(di)) { - ret = PTR_ERR(di); - goto out; - } - if (subvol) { - ret = btrfs_mksubvol(&file->f_path, vol_args->name, - file->f_path.dentry->d_inode->i_mode, - namelen, NULL); + ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen, + NULL); } else { struct inode *src_inode; src_file = fget(vol_args->fd); @@ -769,17 +676,156 @@ static noinline int btrfs_ioctl_snap_create(struct file *file, fput(src_file); goto out; } - ret = btrfs_mksubvol(&file->f_path, vol_args->name, - file->f_path.dentry->d_inode->i_mode, - namelen, BTRFS_I(src_inode)->root); + ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen, + BTRFS_I(src_inode)->root); fput(src_file); } - out: kfree(vol_args); return ret; } +/* + * helper to check if the subvolume references other subvolumes + */ +static noinline int may_destroy_subvol(struct btrfs_root *root) +{ + struct btrfs_path *path; + struct btrfs_key key; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = root->root_key.objectid; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = (u64)-1; + + ret = btrfs_search_slot(NULL, root->fs_info->tree_root, + &key, path, 0, 0); + if (ret < 0) + goto out; + BUG_ON(ret == 0); + + ret = 0; + if (path->slots[0] > 0) { + path->slots[0]--; + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + if (key.objectid == root->root_key.objectid && + key.type == BTRFS_ROOT_REF_KEY) + ret = -ENOTEMPTY; + } +out: + btrfs_free_path(path); + return ret; +} + +static noinline int btrfs_ioctl_snap_destroy(struct file *file, + void __user *arg) +{ + struct dentry *parent = fdentry(file); + struct dentry *dentry; + struct inode *dir = parent->d_inode; + struct inode *inode; + struct btrfs_root *root = BTRFS_I(dir)->root; + struct btrfs_root *dest = NULL; + struct btrfs_ioctl_vol_args *vol_args; + struct btrfs_trans_handle *trans; + int namelen; + int ret; + int err = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) + return PTR_ERR(vol_args); + + vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; + namelen = strlen(vol_args->name); + if (strchr(vol_args->name, '/') || + strncmp(vol_args->name, "..", namelen) == 0) { + err = -EINVAL; + goto out; + } + + err = mnt_want_write(file->f_path.mnt); + if (err) + goto out; + + mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); + dentry = lookup_one_len(vol_args->name, parent, namelen); + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + goto out_unlock_dir; + } + + if (!dentry->d_inode) { + err = -ENOENT; + goto out_dput; + } + + inode = dentry->d_inode; + if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) { + err = -EINVAL; + goto out_dput; + } + + dest = BTRFS_I(inode)->root; + + mutex_lock(&inode->i_mutex); + err = d_invalidate(dentry); + if (err) + goto out_unlock; + + down_write(&root->fs_info->subvol_sem); + + err = may_destroy_subvol(dest); + if (err) + goto out_up_write; + + trans = btrfs_start_transaction(root, 1); + ret = btrfs_unlink_subvol(trans, root, dir, + dest->root_key.objectid, + dentry->d_name.name, + dentry->d_name.len); + BUG_ON(ret); + + btrfs_record_root_in_trans(trans, dest); + + memset(&dest->root_item.drop_progress, 0, + sizeof(dest->root_item.drop_progress)); + dest->root_item.drop_level = 0; + btrfs_set_root_refs(&dest->root_item, 0); + + ret = btrfs_insert_orphan_item(trans, + root->fs_info->tree_root, + dest->root_key.objectid); + BUG_ON(ret); + + ret = btrfs_commit_transaction(trans, root); + BUG_ON(ret); + inode->i_flags |= S_DEAD; +out_up_write: + up_write(&root->fs_info->subvol_sem); +out_unlock: + mutex_unlock(&inode->i_mutex); + if (!err) { + btrfs_invalidate_inodes(dest); + d_delete(dentry); + } +out_dput: + dput(dentry); +out_unlock_dir: + mutex_unlock(&dir->i_mutex); + mnt_drop_write(file->f_path.mnt); +out: + kfree(vol_args); + return err; +} + static int btrfs_ioctl_defrag(struct file *file) { struct inode *inode = fdentry(file)->d_inode; @@ -853,8 +899,8 @@ static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) return ret; } -static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, - u64 off, u64 olen, u64 destoff) +static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, + u64 off, u64 olen, u64 destoff) { struct inode *inode = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; @@ -1246,6 +1292,8 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_ioctl_snap_create(file, argp, 0); case BTRFS_IOC_SUBVOL_CREATE: return btrfs_ioctl_snap_create(file, argp, 1); + case BTRFS_IOC_SNAP_DESTROY: + return btrfs_ioctl_snap_destroy(file, argp); case BTRFS_IOC_DEFRAG: return btrfs_ioctl_defrag(file); case BTRFS_IOC_RESIZE: diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index b320b103fa1..bc49914475e 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -65,5 +65,6 @@ struct btrfs_ioctl_clone_range_args { #define BTRFS_IOC_SUBVOL_CREATE _IOW(BTRFS_IOCTL_MAGIC, 14, \ struct btrfs_ioctl_vol_args) - +#define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \ + struct btrfs_ioctl_vol_args) #endif diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 3be16ccc7ee..48a50426063 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -3203,6 +3203,7 @@ static int check_extent_flags(u64 flags) return 0; } + static noinline_for_stack int relocate_block_group(struct reloc_control *rc) { struct rb_root blocks = RB_ROOT; @@ -3220,6 +3221,9 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc) if (!path) return -ENOMEM; + rc->extents_found = 0; + rc->extents_skipped = 0; + rc->search_start = rc->block_group->key.objectid; clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY, GFP_NOFS); @@ -3475,14 +3479,15 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start) btrfs_wait_ordered_extents(fs_info->tree_root, 0); while (1) { - mutex_lock(&fs_info->cleaner_mutex); - btrfs_clean_old_snapshots(fs_info->tree_root); - mutex_unlock(&fs_info->cleaner_mutex); - rc->extents_found = 0; rc->extents_skipped = 0; + mutex_lock(&fs_info->cleaner_mutex); + + btrfs_clean_old_snapshots(fs_info->tree_root); ret = relocate_block_group(rc); + + mutex_unlock(&fs_info->cleaner_mutex); if (ret < 0) { err = ret; break; @@ -3530,6 +3535,26 @@ out: return err; } +static noinline_for_stack int mark_garbage_root(struct btrfs_root *root) +{ + struct btrfs_trans_handle *trans; + int ret; + + trans = btrfs_start_transaction(root->fs_info->tree_root, 1); + + memset(&root->root_item.drop_progress, 0, + sizeof(root->root_item.drop_progress)); + root->root_item.drop_level = 0; + btrfs_set_root_refs(&root->root_item, 0); + ret = btrfs_update_root(trans, root->fs_info->tree_root, + &root->root_key, &root->root_item); + BUG_ON(ret); + + ret = btrfs_end_transaction(trans, root->fs_info->tree_root); + BUG_ON(ret); + return 0; +} + /* * recover relocation interrupted by system crash. * @@ -3589,8 +3614,12 @@ int btrfs_recover_relocation(struct btrfs_root *root) fs_root = read_fs_root(root->fs_info, reloc_root->root_key.offset); if (IS_ERR(fs_root)) { - err = PTR_ERR(fs_root); - goto out; + ret = PTR_ERR(fs_root); + if (ret != -ENOENT) { + err = ret; + goto out; + } + mark_garbage_root(reloc_root); } } diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c index 5ef72599a58..9351428f30e 100644 --- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -94,17 +94,23 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, goto out; BUG_ON(ret == 0); + if (path->slots[0] == 0) { + ret = 1; + goto out; + } l = path->nodes[0]; - BUG_ON(path->slots[0] == 0); slot = path->slots[0] - 1; btrfs_item_key_to_cpu(l, &found_key, slot); - if (found_key.objectid != objectid) { + if (found_key.objectid != objectid || + found_key.type != BTRFS_ROOT_ITEM_KEY) { ret = 1; goto out; } - read_extent_buffer(l, item, btrfs_item_ptr_offset(l, slot), - sizeof(*item)); - memcpy(key, &found_key, sizeof(found_key)); + if (item) + read_extent_buffer(l, item, btrfs_item_ptr_offset(l, slot), + sizeof(*item)); + if (key) + memcpy(key, &found_key, sizeof(found_key)); ret = 0; out: btrfs_free_path(path); @@ -249,6 +255,59 @@ err: return ret; } +int btrfs_find_orphan_roots(struct btrfs_root *tree_root) +{ + struct extent_buffer *leaf; + struct btrfs_path *path; + struct btrfs_key key; + int err = 0; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = BTRFS_ORPHAN_OBJECTID; + key.type = BTRFS_ORPHAN_ITEM_KEY; + key.offset = 0; + + while (1) { + ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0); + if (ret < 0) { + err = ret; + break; + } + + leaf = path->nodes[0]; + if (path->slots[0] >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(tree_root, path); + if (ret < 0) + err = ret; + if (ret != 0) + break; + leaf = path->nodes[0]; + } + + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + btrfs_release_path(tree_root, path); + + if (key.objectid != BTRFS_ORPHAN_OBJECTID || + key.type != BTRFS_ORPHAN_ITEM_KEY) + break; + + ret = btrfs_find_dead_roots(tree_root, key.offset); + if (ret) { + err = ret; + break; + } + + key.offset++; + } + + btrfs_free_path(path); + return err; +} + /* drop the root item for 'key' from 'root' */ int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_key *key) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 6d6d06cb6df..0242c8babae 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -676,6 +676,7 @@ static int btrfs_unfreeze(struct super_block *sb) } static struct super_operations btrfs_super_ops = { + .drop_inode = btrfs_drop_inode, .delete_inode = btrfs_delete_inode, .put_super = btrfs_put_super, .sync_fs = btrfs_sync_fs, diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 915077725fe..88f866f85e7 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -104,7 +104,6 @@ static noinline int record_root_in_trans(struct btrfs_trans_handle *trans, { if (root->ref_cows && root->last_trans < trans->transid) { WARN_ON(root == root->fs_info->extent_root); - WARN_ON(root->root_item.refs == 0); WARN_ON(root->commit_root != root->node); radix_tree_tag_set(&root->fs_info->fs_roots_radix, @@ -1078,8 +1077,13 @@ int btrfs_clean_old_snapshots(struct btrfs_root *root) while (!list_empty(&list)) { root = list_entry(list.next, struct btrfs_root, root_list); - list_del_init(&root->root_list); - btrfs_drop_snapshot(root, 0); + list_del(&root->root_list); + + if (btrfs_header_backref_rev(root->node) < + BTRFS_MIXED_BACKREF_REV) + btrfs_drop_snapshot(root, 0); + else + btrfs_drop_snapshot(root, 1); } return 0; } diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 6e674d76186..4d7d9abef42 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -2841,7 +2841,7 @@ static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans, if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb) break; - if (parent == sb->s_root) + if (IS_ROOT(parent)) break; parent = parent->d_parent; @@ -2880,6 +2880,12 @@ int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, goto end_no_trans; } + if (root != BTRFS_I(inode)->root || + btrfs_root_refs(&root->root_item) == 0) { + ret = 1; + goto end_no_trans; + } + ret = check_parent_dirs_for_sync(trans, inode, parent, sb, last_committed); if (ret) @@ -2907,12 +2913,15 @@ int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, break; inode = parent->d_inode; + if (root != BTRFS_I(inode)->root) + break; + if (BTRFS_I(inode)->generation > root->fs_info->last_trans_committed) { ret = btrfs_log_inode(trans, root, inode, inode_only); BUG_ON(ret); } - if (parent == sb->s_root) + if (IS_ROOT(parent)) break; parent = parent->d_parent; -- cgit v1.2.3-70-g09d2 From a57195214358b75807a74bad96a8601a36262af7 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Thu, 24 Sep 2009 09:17:31 -0400 Subject: Btrfs: check size of inode backref before adding hardlink For every hardlink in btrfs, there is a corresponding inode back reference. All inode back references for hardlinks in a given directory are stored in single b-tree item. The size of b-tree item is limited by the size of b-tree leaf, so we can only create limited number of hardlinks to a given file in a directory. The original code lacks of the check, it oops if the number of hardlinks goes over the limit. This patch fixes the issue by adding check to btrfs_link and btrfs_rename. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 6 ++++++ fs/btrfs/inode-item.c | 2 ++ fs/btrfs/inode.c | 53 ++++++++++++++++++++++++++++----------------------- 3 files changed, 37 insertions(+), 24 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 3fdcc0512d3..ec96f3a6d53 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -2853,6 +2853,12 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans, int split; int num_doubles = 0; + l = path->nodes[0]; + slot = path->slots[0]; + if (extend && data_size + btrfs_item_size_nr(l, slot) + + sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root)) + return -EOVERFLOW; + /* first try to make some room by pushing left and right */ if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY) { wret = push_leaf_right(trans, root, path, data_size, 0); diff --git a/fs/btrfs/inode-item.c b/fs/btrfs/inode-item.c index fc6f4a7f640..72ce3c173d6 100644 --- a/fs/btrfs/inode-item.c +++ b/fs/btrfs/inode-item.c @@ -149,6 +149,8 @@ int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans, ptr = (unsigned long)(ref + 1); ret = 0; } else if (ret < 0) { + if (ret == -EOVERFLOW) + ret = -EMLINK; goto out; } else { ref = btrfs_item_ptr(path->nodes[0], path->slots[0], diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index db9cbd91eb4..19fcde289dd 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4133,18 +4133,16 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir, err = btrfs_add_nondir(trans, dentry, inode, 1, index); - if (err) - drop_inode = 1; - - btrfs_update_inode_block_group(trans, dir); - err = btrfs_update_inode(trans, root, inode); - - if (err) + if (err) { drop_inode = 1; + } else { + btrfs_update_inode_block_group(trans, dir); + err = btrfs_update_inode(trans, root, inode); + BUG_ON(err); + btrfs_log_new_name(trans, inode, NULL, dentry->d_parent); + } nr = trans->blocks_used; - - btrfs_log_new_name(trans, inode, NULL, dentry->d_parent); btrfs_end_transaction_throttle(trans, root); fail: if (drop_inode) { @@ -5087,23 +5085,26 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, down_read(&root->fs_info->subvol_sem); trans = btrfs_start_transaction(root, 1); + btrfs_set_trans_block_group(trans, new_dir); if (dest != root) btrfs_record_root_in_trans(trans, dest); - /* - * make sure the inode gets flushed if it is replacing - * something. - */ - if (new_inode && new_inode->i_size && - old_inode && S_ISREG(old_inode->i_mode)) { - btrfs_add_ordered_operation(trans, root, old_inode); - } + ret = btrfs_set_inode_index(new_dir, &index); + if (ret) + goto out_fail; - if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) { + if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) { /* force full log commit if subvolume involved. */ root->fs_info->last_trans_log_full_commit = trans->transid; } else { + ret = btrfs_insert_inode_ref(trans, dest, + new_dentry->d_name.name, + new_dentry->d_name.len, + old_inode->i_ino, + new_dir->i_ino, index); + if (ret) + goto out_fail; /* * this is an ugly little race, but the rename is required * to make sure that if we crash, the inode is either at the @@ -5113,8 +5114,14 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, */ btrfs_pin_log_trans(root); } - - btrfs_set_trans_block_group(trans, new_dir); + /* + * make sure the inode gets flushed if it is replacing + * something. + */ + if (new_inode && new_inode->i_size && + old_inode && S_ISREG(old_inode->i_mode)) { + btrfs_add_ordered_operation(trans, root, old_inode); + } old_dir->i_ctime = old_dir->i_mtime = ctime; new_dir->i_ctime = new_dir->i_mtime = ctime; @@ -5159,12 +5166,10 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, BUG_ON(ret); } } - ret = btrfs_set_inode_index(new_dir, &index); - BUG_ON(ret); ret = btrfs_add_link(trans, new_dir, old_inode, new_dentry->d_name.name, - new_dentry->d_name.len, 1, index); + new_dentry->d_name.len, 0, index); BUG_ON(ret); if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) { @@ -5172,7 +5177,7 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, new_dentry->d_parent); btrfs_end_log_trans(root); } - +out_fail: btrfs_end_transaction_throttle(trans, root); if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) -- cgit v1.2.3-70-g09d2 From f679a84034be6f7da123be786bbd8838bf3e9207 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Thu, 24 Sep 2009 09:17:31 -0400 Subject: Btrfs: don't rename file into dummy directory A recent change enforces only one access point to each subvolume. The first directory entry (the one added when the subvolume/snapshot was created) is treated as valid access point, all other subvolume links are linked to dummy empty directories. The dummy directories are temporary inodes that only in memory, so we can not rename file into them. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/inode.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 19fcde289dd..01c5f8b5a34 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5055,6 +5055,9 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, u64 root_objectid; int ret; + if (new_dir->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) + return -EPERM; + /* we only allow rename subvolume link between subvolumes */ if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) return -EXDEV; -- cgit v1.2.3-70-g09d2