From 0c476a5d7f63bdae0b6188a191a6e9eb8f1024d7 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney Date: Fri, 18 Nov 2016 21:52:40 -0500 Subject: [PATCH] btrfs: Ensure proper sector alignment for btrfs_free_reserved_data_space This fixes the WARN_ON on BTRFS_I(inode)->reserved_extents in btrfs_destroy_inode and the WARN_ON on nonzero delalloc bytes on umount with qgroups enabled. I was able to reproduce this by setting up a small (~500kb) quota limit and writing a file one byte at a time until I hit the limit. The warnings would all hit on umount. The root cause is that we would reserve a block-sized range in both the reservation and the quota in btrfs_check_data_free_space, but if we encountered a problem (like e.g. EDQUOT), we would only release the single byte in the qgroup reservation. That caused an iotree state split, which increased the number of outstanding extents, in turn disallowing releasing the metadata reservation. Signed-off-by: Jeff Mahoney Reviewed-by: Qu Wenruo Signed-off-by: David Sterba --- fs/btrfs/extent-tree.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 78fcc67e7b8c..c17b0d1b081f 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4322,6 +4322,13 @@ void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start, */ void btrfs_free_reserved_data_space(struct inode *inode, u64 start, u64 len) { + struct btrfs_root *root = BTRFS_I(inode)->root; + + /* Make sure the range is aligned to sectorsize */ + len = round_up(start + len, root->sectorsize) - + round_down(start, root->sectorsize); + start = round_down(start, root->sectorsize); + btrfs_free_reserved_data_space_noquota(inode, start, len); btrfs_qgroup_free_data(inode, start, len); } -- 2.20.1