[XFS] implement IHOLD/IRELE directly

Now that all direct calls to VN_HOLD/VN_RELE are gone we can implement
IHOLD/IRELE directly.

For the IHOLD case also replace igrab with a direct increment of i_count
because we are guaranteed to already have a live and referenced inode by
the VFS. Also remove the vn_hold statistic because it's been rather
meaningless for some time with most references done by other callers.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31764a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

3 files changed, 12 insertions, 37 deletions

diff --git a/fs/xfs/linux-2.6/xfs_vnode.c b/fs/xfs/linux-2.6/xfs_vnode.c
index 4af972b0166c..1c5a34f5c3c0 100644
--- a/fs/xfs/linux-2.6/xfs_vnode.c
+++ b/fs/xfs/linux-2.6/xfs_vnode.c
@@ -82,24 +82,6 @@ vn_ioerror(
                 xfs_do_force_shutdown(ip->i_mount, SHUTDOWN_DEVICE_REQ, f, l);
 }
 
-
-/*
- * Add a reference to a referenced vnode.
- */
-bhv_vnode_t *
-vn_hold(
-        bhv_vnode_t     *vp)
-{
-        struct inode    *inode;
-
-        XFS_STATS_INC(vn_hold);
-
-        inode = igrab(vp);
-        ASSERT(inode);
-
-        return vp;
-}
-
 #ifdef  XFS_INODE_TRACE
 
 /*
diff --git a/fs/xfs/linux-2.6/xfs_vnode.h b/fs/xfs/linux-2.6/xfs_vnode.h
index cc53687ff826..0d7eac03bdf0 100644
--- a/fs/xfs/linux-2.6/xfs_vnode.h
+++ b/fs/xfs/linux-2.6/xfs_vnode.h
@@ -69,22 +69,18 @@ static inline int vn_count(bhv_vnode_t *vp)
         return atomic_read(&vp->i_count);
 }
 
-/*
- * Vnode reference counting functions (and macros for compatibility).
- */
-extern bhv_vnode_t      *vn_hold(bhv_vnode_t *);
-
-#if defined(XFS_INODE_TRACE)
-#define VN_HOLD(vp)             \
-        ((void)vn_hold(vp),     \
-          xfs_itrace_hold(XFS_I(vp), __FILE__, __LINE__, (inst_t *)__return_address))
-#define VN_RELE(vp)             \
-          (xfs_itrace_rele(XFS_I(vp), __FILE__, __LINE__, (inst_t *)__return_address), \
-           iput(vp))
-#else
-#define VN_HOLD(vp)             ((void)vn_hold(vp))
-#define VN_RELE(vp)             (iput(vp))
-#endif
+#define IHOLD(ip) \
+do { \
+        ASSERT(atomic_read(&VFS_I(ip)->i_count) > 0) ; \
+        atomic_inc(&(VFS_I(ip)->i_count)); \
+        xfs_itrace_hold((ip), __FILE__, __LINE__, (inst_t *)__return_address); \
+} while (0)
+
+#define IRELE(ip) \
+do { \
+        xfs_itrace_rele((ip), __FILE__, __LINE__, (inst_t *)__return_address); \
+        iput(VFS_I(ip)); \
+} while (0)
 
 static inline bhv_vnode_t *vn_grab(bhv_vnode_t *vp)
 {
diff --git a/fs/xfs/xfs_utils.h b/fs/xfs/xfs_utils.h
index 7b533dfea603..ef321225d269 100644
--- a/fs/xfs/xfs_utils.h
+++ b/fs/xfs/xfs_utils.h
@@ -18,9 +18,6 @@
 #ifndef __XFS_UTILS_H__
 #define __XFS_UTILS_H__
 
-#define IRELE(ip)       VN_RELE(VFS_I(ip))
-#define IHOLD(ip)       VN_HOLD(VFS_I(ip))
-
 extern int xfs_truncate_file(xfs_mount_t *, xfs_inode_t *);
 extern int xfs_dir_ialloc(xfs_trans_t **, xfs_inode_t *, mode_t, xfs_nlink_t,
                                 xfs_dev_t, cred_t *, prid_t, int,