From 033da48fda9d56e28b3fe3ef87ef6fd43290f554 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 19 Oct 2009 04:05:26 +0000 Subject: xfs: reset the i_iolock lock class in the reclaim path The iolock is used for protecting reads, writes and block truncates against each other. We have two classes of callers, the first one is induced by a file operation and requires a reference to the inode be held and not dropped after the operation is done: - xfs_vm_vmap, xfs_vn_fallocate, xfs_read, xfs_write, xfs_splice_read, xfs_splice_write and xfs_setattr are all implementations of VFS methods that require a live inode - xfs_getbmap and xfs_swap_extents are ioctl subcommand for which the same is true - xfs_truncate_file is only called on quota inodes just returned from xfs_iget - xfs_sync_inode_data does the lock just after an igrab() - xfs_filestream_associate and xfs_filestream_new_ag take the iolock on the parent inode of an inode which by VFS rules must be referenced And we have various calls to truncate blocks past EOF or the whole file when dropping the last reference to an inode. Unfortunately lockdep complains when we do memory allocations that can recurse into the filesystem in the first class because the second class happens to take the same lock. To avoid this re-init the iolock in the beginning of xfs_fs_clear_inode to get a new lock class. Signed-off-by: Christoph Hellwig Reviewed-by: Alex Elder Signed-off-by: Alex Elder --- fs/xfs/xfs_iget.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs/xfs/xfs_iget.c') diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c index 80e526489be5..cc72c561ff52 100644 --- a/fs/xfs/xfs_iget.c +++ b/fs/xfs/xfs_iget.c @@ -73,6 +73,9 @@ xfs_inode_alloc( ASSERT(atomic_read(&ip->i_pincount) == 0); ASSERT(!spin_is_locked(&ip->i_flags_lock)); ASSERT(completion_done(&ip->i_flush)); + ASSERT(!rwsem_is_locked(&ip->i_iolock.mr_lock)); + + mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino); /* initialise the xfs inode */ ip->i_ino = ino; -- cgit v1.2.3