[PATCH] xfs: clarify lock ordering comment

From: Ross Zwisler
Date: Thu Oct 08 2015 - 17:58:11 EST


Replace "i_mmap_lock" with "mmap_lock" in the lock ordering comment above
xfs_filemap_page_mkwrite(). The lock in question is actually the
XFS_MMAPLOCK_SHARED rw_semaphore (no leading "i"), and this comment is
easily confused with the "i_mmap_lock_[read|write]" functions that operate
on struct address_space->i_mmap_rwsem. This clarification is especially
important because address_space->i_mmap_rwsem is taken down in the DAX
code as part of this fault path.

Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
---
fs/xfs/xfs_file.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f429662..b190033 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1477,7 +1477,7 @@ xfs_file_llseek(
*
* mmap_sem (MM)
* sb_start_pagefault(vfs, freeze)
- * i_mmap_lock (XFS - truncate serialisation)
+ * mmap_lock (XFS - truncate serialisation)
* page_lock (MM)
* i_lock (XFS - extent map serialisation)
*/
--
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/