xfs: fix mmap_sem/iolock inversion in xfs_free_eofblocks

When xfs_free_eofblocks is called from ->release the VM might already
hold the mmap_sem, but in the write path we take the iolock before
taking the mmap_sem in the generic write code.

Switch xfs_free_eofblocks to only trylock the iolock if called from
->release and skip trimming the prellocated blocks in that case.
We'll still free them later on the final iput.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>

1 files changed, 0 insertions, 7 deletions

diff --git a/fs/xfs/xfs_rw.h b/fs/xfs/xfs_rw.h
index f5e4874c37d8..726014d1c925 100644
--- a/fs/xfs/xfs_rw.h
+++ b/fs/xfs/xfs_rw.h
@@ -37,13 +37,6 @@ xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
 }
 
 /*
- * Flags for xfs_free_eofblocks
- */
-#define XFS_FREE_EOF_LOCK       (1<<0)
-#define XFS_FREE_EOF_NOLOCK     (1<<1)
-
-
-/*
  * helper function to extract extent size hint from inode
  */
 STATIC_INLINE xfs_extlen_t