xfs: make sure to free the real-time inodes in the mount error path

When mount fails after allocating the real-time inodes we currently leak
them.  Add a new helper to free the real-time inodes which can be used by
both the mount and unmount path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>

fs/xfs/xfs_mount.c

@@ -1138,7 +1138,7 @@ xfs_mountfs(
 		error = xfs_mount_log_sb(mp, mp->m_update_flags);
 		if (error) {
 			cmn_err(CE_WARN, "XFS: failed to write sb changes");
-			goto out_rele_rip;
+			goto out_rtunmount;
 		}
 	}
 
@@ -1147,7 +1147,7 @@ xfs_mountfs(
 	 */
 	error = XFS_QM_INIT(mp, &quotamount, &quotaflags);
 	if (error)
-		goto out_rele_rip;
+		goto out_rtunmount;
 
 	/*
 	 * Finish recovering the file system.  This part needed to be
@@ -1157,7 +1157,7 @@ xfs_mountfs(
 	error = xfs_log_mount_finish(mp);
 	if (error) {
 		cmn_err(CE_WARN, "XFS: log mount finish failed");
-		goto out_rele_rip;
+		goto out_rtunmount;
 	}
 
 	/*
@@ -1165,7 +1165,7 @@ xfs_mountfs(
 	 */
 	error = XFS_QM_MOUNT(mp, quotamount, quotaflags);
 	if (error)
-		goto out_rele_rip;
+		goto out_rtunmount;
 
 	/*
 	 * Now we are mounted, reserve a small amount of unused space for
@@ -1189,6 +1189,8 @@ xfs_mountfs(
 
 	return 0;
 
+ out_rtunmount:
+	xfs_rtunmount_inodes(mp);
  out_rele_rip:
 	IRELE(rip);
  out_log_dealloc:
@@ -1219,10 +1221,7 @@ xfs_unmountfs(
 	 */
 	XFS_QM_UNMOUNT(mp);
 
-	if (mp->m_rbmip)
-		IRELE(mp->m_rbmip);
-	if (mp->m_rsumip)
-		IRELE(mp->m_rsumip);
+	xfs_rtunmount_inodes(mp);
 	IRELE(mp->m_rootip);
 
 	/*

fs/xfs/xfs_rtalloc.c

@@ -2288,6 +2288,16 @@ xfs_rtmount_inodes(
 	return 0;
 }
 
+void
+xfs_rtunmount_inodes(
+	struct xfs_mount	*mp)
+{
+	if (mp->m_rbmip)
+		IRELE(mp->m_rbmip);
+	if (mp->m_rsumip)
+		IRELE(mp->m_rsumip);
+}
+
 /*
  * Pick an extent for allocation at the start of a new realtime file.
  * Use the sequence number stored in the atime field of the bitmap inode.

fs/xfs/xfs_rtalloc.h

@@ -108,6 +108,9 @@ xfs_rtfree_extent(
 int					/* error */
 xfs_rtmount_init(
 	struct xfs_mount	*mp);	/* file system mount structure */
+void
+xfs_rtunmount_inodes(
+	struct xfs_mount	*mp);
 
 /*
  * Get the bitmap and summary inodes into the mount structure
@@ -146,6 +149,7 @@ xfs_growfs_rt(
 # define xfs_growfs_rt(mp,in)                           (ENOSYS)
 # define xfs_rtmount_init(m)    (((mp)->m_sb.sb_rblocks == 0)? 0 : (ENOSYS))
 # define xfs_rtmount_inodes(m)  (((mp)->m_sb.sb_rblocks == 0)? 0 : (ENOSYS))
+# define xfs_rtunmount_inodes(m)
 #endif	/* CONFIG_XFS_RT */
 
 #endif	/* __KERNEL__ */