From db804f23a72bada58f083dfad6a65d019ddb3bd4 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Tue, 10 Jan 2012 16:41:01 +0800 Subject: Btrfs: add pinned extents to on-disk free space cache correctly I got this while running xfstests: [24256.836098] block group 317849600 has an wrong amount of free space [24256.836100] btrfs: failed to load free space cache for block group 317849600 We should clamp the extent returned by find_first_extent_bit(), so the start of the extent won't smaller than the start of the block group. Signed-off-by: Li Zefan --- fs/btrfs/free-space-cache.c | 41 ++++++++++++++++++++--------------------- 1 file changed, 20 insertions(+), 21 deletions(-) (limited to 'fs') diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index ec23d43d0c3..01840ef95a3 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -838,7 +838,7 @@ int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode, struct io_ctl io_ctl; struct list_head bitmap_list; struct btrfs_key key; - u64 start, end, len; + u64 start, extent_start, extent_end, len; int entries = 0; int bitmaps = 0; int ret; @@ -857,25 +857,12 @@ int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode, struct btrfs_free_cluster, block_group_list); - /* - * We shouldn't have switched the pinned extents yet so this is the - * right one - */ - unpin = root->fs_info->pinned_extents; - /* Lock all pages first so we can lock the extent safely. */ io_ctl_prepare_pages(&io_ctl, inode, 0); lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1, 0, &cached_state, GFP_NOFS); - /* - * When searching for pinned extents, we need to start at our start - * offset. - */ - if (block_group) - start = block_group->key.objectid; - node = rb_first(&ctl->free_space_offset); if (!node && cluster) { node = rb_first(&cluster->root); @@ -918,9 +905,20 @@ int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode, * We want to add any pinned extents to our free space cache * so we don't leak the space */ + + /* + * We shouldn't have switched the pinned extents yet so this is the + * right one + */ + unpin = root->fs_info->pinned_extents; + + if (block_group) + start = block_group->key.objectid; + while (block_group && (start < block_group->key.objectid + block_group->key.offset)) { - ret = find_first_extent_bit(unpin, start, &start, &end, + ret = find_first_extent_bit(unpin, start, + &extent_start, &extent_end, EXTENT_DIRTY); if (ret) { ret = 0; @@ -928,20 +926,21 @@ int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode, } /* This pinned extent is out of our range */ - if (start >= block_group->key.objectid + + if (extent_start >= block_group->key.objectid + block_group->key.offset) break; - len = block_group->key.objectid + - block_group->key.offset - start; - len = min(len, end + 1 - start); + extent_start = max(extent_start, start); + extent_end = min(block_group->key.objectid + + block_group->key.offset, extent_end + 1); + len = extent_end - extent_start; entries++; - ret = io_ctl_add_entry(&io_ctl, start, len, NULL); + ret = io_ctl_add_entry(&io_ctl, extent_start, len, NULL); if (ret) goto out_nospc; - start = end + 1; + start = extent_end; } /* Write out the bitmaps */ -- cgit v1.2.3