[XFS] add helper to get xfs_inode from vnode

SGI-PV: 947206
SGI-Modid: xfs-linux-melb:xfs-kern:203960a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 52707b5..d1db8c1 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -54,7 +54,6 @@
 	int		mask)
 {
 	xfs_inode_t	*ip;
-	bhv_desc_t	*bdp;
 	vnode_t		*vp = LINVFS_GET_VP(inode);
 	loff_t		isize = i_size_read(inode);
 	loff_t		offset = page_offset(page);
@@ -63,8 +62,7 @@
 	if (page_has_buffers(page))
 		xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
 
-	bdp = vn_bhv_lookup(VN_BHV_HEAD(vp), &xfs_vnodeops);
-	ip = XFS_BHVTOI(bdp);
+	ip = xfs_vtoi(vp);
 	if (!ip->i_rwtrace)
 		return;
 
diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c
index 06111d0..ced4404 100644
--- a/fs/xfs/linux-2.6/xfs_file.c
+++ b/fs/xfs/linux-2.6/xfs_file.c
@@ -509,16 +509,14 @@
 	vnode_t		*vp = LINVFS_GET_VP(inode);
 	xfs_mount_t	*mp = XFS_VFSTOM(vp->v_vfsp);
 	int		error = 0;
-	bhv_desc_t	*bdp;
 	xfs_inode_t	*ip;
 
 	if (vp->v_vfsp->vfs_flag & VFS_DMI) {
-		bdp = vn_bhv_lookup(VN_BHV_HEAD(vp), &xfs_vnodeops);
-		if (!bdp) {
+		ip = xfs_vtoi(vp);
+		if (!ip) {
 			error = -EINVAL;
 			goto open_exec_out;
 		}
-		ip = XFS_BHVTOI(bdp);
 		if (DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_READ)) {
 			error = -XFS_SEND_DATA(mp, DM_EVENT_READ, vp,
 					       0, 0, 0, NULL);
diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c
index 7ad7b68..b3b2cfd 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl.c
@@ -145,13 +145,10 @@
 
 	if (cmd != XFS_IOC_PATH_TO_FSHANDLE) {
 		xfs_inode_t	*ip;
-		bhv_desc_t	*bhv;
 		int		lock_mode;
 
 		/* need to get access to the xfs_inode to read the generation */
-		bhv = vn_bhv_lookup_unlocked(VN_BHV_HEAD(vp), &xfs_vnodeops);
-		ASSERT(bhv);
-		ip = XFS_BHVTOI(bhv);
+		ip = xfs_vtoi(vp);
 		ASSERT(ip);
 		lock_mode = xfs_ilock_map_shared(ip);
 
diff --git a/fs/xfs/linux-2.6/xfs_iops.c b/fs/xfs/linux-2.6/xfs_iops.c
index fe5e989..d388d14 100644
--- a/fs/xfs/linux-2.6/xfs_iops.c
+++ b/fs/xfs/linux-2.6/xfs_iops.c
@@ -59,6 +59,22 @@
 	(S_ISDIR(inode->i_mode) && inode->i_sb->s_flags & MS_NODIRATIME))
 
 /*
+ * Get a XFS inode from a given vnode.
+ */
+xfs_inode_t *
+xfs_vtoi(
+	struct vnode	*vp)
+{
+	bhv_desc_t      *bdp;
+
+	bdp = bhv_lookup_range(VN_BHV_HEAD(vp),
+			VNODE_POSITION_XFS, VNODE_POSITION_XFS);
+	if (unlikely(bdp == NULL))
+		return NULL;
+	return XFS_BHVTOI(bdp);
+}
+
+/*
  * Bring the atime in the XFS inode uptodate.
  * Used before logging the inode to disk or when the Linux inode goes away.
  */