Refactor xfs_isilocked() to use newly introduced __xfs_rwsem_islocked().
__xfs_rwsem_islocked() is a helper function which encapsulates checking
state of rw_semaphores hold by inode.
Signed-off-by: Pavel Reichl <preichl@xxxxxxxxxx>
Suggested-by: Dave Chinner <dchinner@xxxxxxxxxx>
Suggested-by: Eric Sandeen <sandeen@xxxxxxxxxx>
Suggested-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
fs/xfs/xfs_inode.c | 48 ++++++++++++++++++++++++++++++++++++++--------
fs/xfs/xfs_inode.h | 21 +++++++++++++-------
2 files changed, 54 insertions(+), 15 deletions(-)
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index c06129cffba9..7c1ceb4df4ec 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -345,9 +345,43 @@ xfs_ilock_demote(
}
#if defined(DEBUG) || defined(XFS_WARN)
-int
+static inline bool
+__xfs_rwsem_islocked(
+ struct rw_semaphore *rwsem,
+ int lock_flags)
+{
+ int arg;
+
+ if (!debug_locks)
+ return rwsem_is_locked(rwsem);
+
+ if (lock_flags & (1 << XFS_SHARED_LOCK_SHIFT)) {
+ /*
+ * The caller could be asking if we have (shared | excl)
+ * access to the lock. Ask lockdep if the rwsem is
+ * locked either for read or write access.
+ *
+ * The caller could also be asking if we have only
+ * shared access to the lock. Holding a rwsem
+ * write-locked implies read access as well, so the
+ * request to lockdep is the same for this case.
+ */
+ arg = -1;
+ } else {
+ /*
+ * The caller is asking if we have only exclusive access
+ * to the lock. Ask lockdep if the rwsem is locked for
+ * write access.
+ */
+ arg = 0;
+ }
+
+ return lockdep_is_held_type(rwsem, arg);
+}
+
+bool
xfs_isilocked(
- xfs_inode_t *ip,
+ struct xfs_inode *ip,
uint lock_flags)
{
if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
@@ -362,15 +396,13 @@ xfs_isilocked(
return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
}
- if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
- if (!(lock_flags & XFS_IOLOCK_SHARED))
- return !debug_locks ||
- lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
- return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
+ if (lock_flags & (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED)) {
+ return __xfs_rwsem_islocked(&VFS_I(ip)->i_rwsem,
+ (lock_flags >> XFS_IOLOCK_FLAG_SHIFT));
}
ASSERT(0);
- return 0;
+ return false;
}
#endif
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index e9a8bb184d1f..77d5655191ab 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -268,12 +268,19 @@ static inline void xfs_ifunlock(struct xfs_inode *ip)
* Bit ranges: 1<<1 - 1<<16-1 -- iolock/ilock modes (bitfield)
* 1<<16 - 1<<32-1 -- lockdep annotation (integers)
*/
-#define XFS_IOLOCK_EXCL (1<<0)
-#define XFS_IOLOCK_SHARED (1<<1)
-#define XFS_ILOCK_EXCL (1<<2)
-#define XFS_ILOCK_SHARED (1<<3)
-#define XFS_MMAPLOCK_EXCL (1<<4)
-#define XFS_MMAPLOCK_SHARED (1<<5)
+
+#define XFS_IOLOCK_FLAG_SHIFT 0
+#define XFS_ILOCK_FLAG_SHIFT 2
+#define XFS_MMAPLOCK_FLAG_SHIFT 4
+
+#define XFS_SHARED_LOCK_SHIFT 1
+
+#define XFS_IOLOCK_EXCL (1 << (XFS_IOLOCK_FLAG_SHIFT))
+#define XFS_IOLOCK_SHARED (XFS_IOLOCK_EXCL << (XFS_SHARED_LOCK_SHIFT))
+#define XFS_ILOCK_EXCL (1 << (XFS_ILOCK_FLAG_SHIFT))
+#define XFS_ILOCK_SHARED (XFS_ILOCK_EXCL << (XFS_SHARED_LOCK_SHIFT))
+#define XFS_MMAPLOCK_EXCL (1 << (XFS_MMAPLOCK_FLAG_SHIFT))
+#define XFS_MMAPLOCK_SHARED (XFS_MMAPLOCK_EXCL << (XFS_SHARED_LOCK_SHIFT))
#define XFS_LOCK_MASK (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED \
| XFS_ILOCK_EXCL | XFS_ILOCK_SHARED \
@@ -412,7 +419,7 @@ void xfs_ilock(xfs_inode_t *, uint);
int xfs_ilock_nowait(xfs_inode_t *, uint);
void xfs_iunlock(xfs_inode_t *, uint);
void xfs_ilock_demote(xfs_inode_t *, uint);
-int xfs_isilocked(xfs_inode_t *, uint);
+bool xfs_isilocked(xfs_inode_t *, uint);
uint xfs_ilock_data_map_shared(struct xfs_inode *);
uint xfs_ilock_attr_map_shared(struct xfs_inode *);
--
2.26.2
