This is going to be used to check if an rwsem is held for write.
Mimicking what current mrlock->mr_writer variable provides but using
the generic rwsem infrastructure. One might argue that redefining the
locked bit is a layering violation since RWSEM_WRITE_LOCKED is not
exposed, however I'd argue back that this is only used in a debugging
scenario and the physical layout of the rwsem is unlikely to change.
Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
---
fs/xfs/xfs_inode.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index b7352bc4c815..499e63da935c 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -345,6 +345,13 @@ xfs_ilock_demote(
}
#if defined(DEBUG) || defined(XFS_WARN)
+static bool is_rwsem_write_locked(struct rw_semaphore *rwsem)
+{
+ /* Copy of RWSEM_WRITE_LOCKED from rwsem.c */
+#define LOCK_BIT (1UL << 0)
+ return atomic_long_read(&rwsem->count) & LOCK_BIT;
+}
+
int
xfs_isilocked(
xfs_inode_t *ip,
--
2.25.1
