xfs: remove xfs_ipin/xfs_iunpin

Inodes are only pinned/unpinned via the inode item methods, and lots of
code relies on that fact.  So remove the separate xfs_ipin/xfs_iunpin
helpers and merge them into their only callers.  This also fixes up
various duplicate and/or incorrect comments.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>

fs/xfs/xfs_inode.c

@@ -2438,34 +2438,6 @@ xfs_idestroy_fork(
 	}
 }
 
-/*
- * Increment the pin count of the given buffer.
- * This value is protected by ipinlock spinlock in the mount structure.
- */
-void
-xfs_ipin(
-	xfs_inode_t	*ip)
-{
-	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
-
-	atomic_inc(&ip->i_pincount);
-}
-
-/*
- * Decrement the pin count of the given inode, and wake up
- * anyone in xfs_iwait_unpin() if the count goes to 0.  The
- * inode must have been previously pinned with a call to xfs_ipin().
- */
-void
-xfs_iunpin(
-	xfs_inode_t	*ip)
-{
-	ASSERT(atomic_read(&ip->i_pincount) > 0);
-
-	if (atomic_dec_and_test(&ip->i_pincount))
-		wake_up(&ip->i_ipin_wait);
-}
-
 /*
  * This is called to unpin an inode.  The caller must have the inode locked
  * in at least shared mode so that the buffer cannot be subsequently pinned

fs/xfs/xfs_inode.h

@@ -471,8 +471,6 @@ int		xfs_itruncate_finish(struct xfs_trans **, xfs_inode_t *,
 int		xfs_iunlink(struct xfs_trans *, xfs_inode_t *);
 
 void		xfs_iext_realloc(xfs_inode_t *, int, int);
-void		xfs_ipin(xfs_inode_t *);
-void		xfs_iunpin(xfs_inode_t *);
 void		xfs_iunpin_wait(xfs_inode_t *);
 int		xfs_iflush(xfs_inode_t *, uint);
 void		xfs_ichgtime(xfs_inode_t *, int);

fs/xfs/xfs_inode_item.c

@@ -535,23 +535,23 @@ xfs_inode_item_format(
 
 /*
  * This is called to pin the inode associated with the inode log
- * item in memory so it cannot be written out.  Do this by calling
- * xfs_ipin() to bump the pin count in the inode while holding the
- * inode pin lock.
+ * item in memory so it cannot be written out.
  */
 STATIC void
 xfs_inode_item_pin(
 	xfs_inode_log_item_t	*iip)
 {
 	ASSERT(xfs_isilocked(iip->ili_inode, XFS_ILOCK_EXCL));
-	xfs_ipin(iip->ili_inode);
+
+	atomic_inc(&iip->ili_inode->i_pincount);
 }
 
 
 /*
  * This is called to unpin the inode associated with the inode log
  * item which was previously pinned with a call to xfs_inode_item_pin().
- * Just call xfs_iunpin() on the inode to do this.
+ *
+ * Also wake up anyone in xfs_iunpin_wait() if the count goes to 0.
  */
 /* ARGSUSED */
 STATIC void
@@ -559,7 +559,11 @@ xfs_inode_item_unpin(
 	xfs_inode_log_item_t	*iip,
 	int			stale)
 {
-	xfs_iunpin(iip->ili_inode);
+	struct xfs_inode	*ip = iip->ili_inode;
+
+	ASSERT(atomic_read(&ip->i_pincount) > 0);
+	if (atomic_dec_and_test(&ip->i_pincount))
+		wake_up(&ip->i_ipin_wait);
 }
 
 /* ARGSUSED */
@@ -568,7 +572,7 @@ xfs_inode_item_unpin_remove(
 	xfs_inode_log_item_t	*iip,
 	xfs_trans_t		*tp)
 {
-	xfs_iunpin(iip->ili_inode);
+	xfs_inode_item_unpin(iip, 0);
 }
 
 /*