From c726de4409a8d3a03877b1ef4342bfe8a15f5e5e Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 30 Nov 2010 15:14:39 +1100 Subject: xfs: fix failed write truncation handling. Since the move to the new truncate sequence we call xfs_setattr to truncate down excessively instanciated blocks. As shown by the testcase in kernel.org BZ #22452 that doesn't work too well. Due to the confusion of the internal inode size, and the VFS inode i_size it zeroes data that it shouldn't. But full blown truncate seems like overkill here. We only instanciate delayed allocations in the write path, and given that we never released the iolock we can't have converted them to real allocations yet either. The only nasty case is pre-existing preallocation which we need to skip. We already do this for page discard during writeback, so make the delayed allocation block punching a generic function and call it from the failed write path as well as xfs_aops_discard_page. The callers are responsible for ensuring that partial blocks are not truncated away, and that they hold the ilock. Based on a fix originally from Christoph Hellwig. This version used filesystem blocks as the range unit. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig --- fs/xfs/xfs_bmap.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/xfs/xfs_bmap.h') diff --git a/fs/xfs/xfs_bmap.h b/fs/xfs/xfs_bmap.h index 71ec9b6ecdf..3651191daea 100644 --- a/fs/xfs/xfs_bmap.h +++ b/fs/xfs/xfs_bmap.h @@ -394,6 +394,11 @@ xfs_bmap_count_blocks( int whichfork, int *count); +int +xfs_bmap_punch_delalloc_range( + struct xfs_inode *ip, + xfs_fileoff_t start_fsb, + xfs_fileoff_t length); #endif /* __KERNEL__ */ #endif /* __XFS_BMAP_H__ */ -- cgit v1.2.3