[XFS] Add lockdep support for XFS

SGI-PV: 963965
SGI-Modid: xfs-linux-melb:xfs-kern:28485a

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>

1 files changed, 46 insertions, 14 deletions

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index cfe7b58c4533..f75afecef8e7 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -382,26 +382,58 @@ xfs_iflags_test(xfs_inode_t *ip, unsigned short flags)
 
 /*
  * Flags for inode locking.
+ * Bit ranges:  1<<1  - 1<<16-1 -- iolock/ilock modes (bitfield)
+ *              1<<16 - 1<<32-1 -- lockdep annotation (integers)
  */
-#define XFS_IOLOCK_EXCL         0x001
-#define XFS_IOLOCK_SHARED       0x002
-#define XFS_ILOCK_EXCL          0x004
-#define XFS_ILOCK_SHARED        0x008
-#define XFS_IUNLOCK_NONOTIFY    0x010
-/*      XFS_IOLOCK_NESTED       0x020 */
-#define XFS_EXTENT_TOKEN_RD     0x040
-#define XFS_SIZE_TOKEN_RD       0x080
+#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_IUNLOCK_NONOTIFY    (1<<4)
+/*      #define XFS_IOLOCK_NESTED       (1<<5)  */
+#define XFS_EXTENT_TOKEN_RD     (1<<6)
+#define XFS_SIZE_TOKEN_RD       (1<<7)
 #define XFS_EXTSIZE_RD          (XFS_EXTENT_TOKEN_RD|XFS_SIZE_TOKEN_RD)
-#define XFS_WILLLEND            0x100   /* Always acquire tokens for lending */
+#define XFS_WILLLEND            (1<<8)  /* Always acquire tokens for lending */
 #define XFS_EXTENT_TOKEN_WR     (XFS_EXTENT_TOKEN_RD | XFS_WILLLEND)
 #define XFS_SIZE_TOKEN_WR       (XFS_SIZE_TOKEN_RD | XFS_WILLLEND)
 #define XFS_EXTSIZE_WR          (XFS_EXTSIZE_RD | XFS_WILLLEND)
-/*      XFS_SIZE_TOKEN_WANT     0x200 */
+/* TODO:XFS_SIZE_TOKEN_WANT     (1<<9) */
 
-#define XFS_LOCK_MASK   \
-        (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL | \
-         XFS_ILOCK_SHARED | XFS_EXTENT_TOKEN_RD | XFS_SIZE_TOKEN_RD | \
-         XFS_WILLLEND)
+#define XFS_LOCK_MASK           (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED \
+                                | XFS_ILOCK_EXCL | XFS_ILOCK_SHARED \
+                                | XFS_EXTENT_TOKEN_RD | XFS_SIZE_TOKEN_RD \
+                                | XFS_WILLLEND)
+
+/*
+ * Flags for lockdep annotations.
+ *
+ * XFS_I[O]LOCK_PARENT - for operations that require locking two inodes
+ * (ie directory operations that require locking a directory inode and
+ * an entry inode).  The first inode gets locked with this flag so it
+ * gets a lockdep subclass of 1 and the second lock will have a lockdep
+ * subclass of 0.
+ *
+ * XFS_I[O]LOCK_INUMORDER - for locking several inodes at the some time
+ * with xfs_lock_inodes().  This flag is used as the starting subclass
+ * and each subsequent lock acquired will increment the subclass by one.
+ * So the first lock acquired will have a lockdep subclass of 2, the
+ * second lock will have a lockdep subclass of 3, and so on.
+ */
+#define XFS_IOLOCK_SHIFT        16
+#define XFS_IOLOCK_PARENT       (1 << XFS_IOLOCK_SHIFT)
+#define XFS_IOLOCK_INUMORDER    (2 << XFS_IOLOCK_SHIFT)
+
+#define XFS_ILOCK_SHIFT         24
+#define XFS_ILOCK_PARENT        (1 << XFS_ILOCK_SHIFT)
+#define XFS_ILOCK_INUMORDER     (2 << XFS_ILOCK_SHIFT)
+
+#define XFS_IOLOCK_DEP_MASK     0x00ff0000
+#define XFS_ILOCK_DEP_MASK      0xff000000
+#define XFS_LOCK_DEP_MASK       (XFS_IOLOCK_DEP_MASK | XFS_ILOCK_DEP_MASK)
+
+#define XFS_IOLOCK_DEP(flags)   (((flags) & XFS_IOLOCK_DEP_MASK) >> XFS_IOLOCK_SHIFT)
+#define XFS_ILOCK_DEP(flags)    (((flags) & XFS_ILOCK_DEP_MASK) >> XFS_ILOCK_SHIFT)
 
 /*
  * Flags for xfs_iflush()