[GFS2] Tidy up mount code.

We no longer lookup ".gfs2_admin" in the root directory in order to
find it, but instead use the inode number given in the superblock.
Both the root directory and the admin directory are now looked up using
the same routine, so the redundant code is removed.

Also, there is no longer a reference to the root inode in the
GFS2 super block. When required this can be retreived via
sb->s_root->d_inode instead.

Assuming that we introduce a metadata filesystem type for GFS, then
this is a first step towards that goal.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 17 insertions, 23 deletions

diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 4c4115f9d960..c3b830bd838b 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -280,27 +280,30 @@ static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
 	return error;
 }
 
-int gfs2_lookup_root(struct gfs2_sbd *sdp)
+static struct inode *gfs2_lookup_root(struct gfs2_sbd *sdp,
+				      const struct gfs2_inum *inum)
 {
         int error;
 	struct gfs2_glock *gl;
 	struct gfs2_inode *ip;
+	struct inode *inode;
 
-	error = gfs2_glock_get(sdp, sdp->sd_sb.sb_root_dir.no_addr,
+	error = gfs2_glock_get(sdp, inum->no_addr,
                                &gfs2_inode_glops, CREATE, &gl);
         if (!error) {
-               	error = gfs2_inode_get(gl, &sdp->sd_sb.sb_root_dir,
+               	error = gfs2_inode_get(gl, inum,
 				       CREATE, &ip);
 		if (!error) {
 			if (!error) 
 				gfs2_inode_min_init(ip, DT_DIR);
-			sdp->sd_root_dir = gfs2_ip2v(ip);
+			inode = gfs2_ip2v(ip);
 			gfs2_inode_put(ip);
+			return inode;
 		}
                 gfs2_glock_put(gl);
         }
 
-        return error;
+        return ERR_PTR(error);
 }
 
 static int init_sb(struct gfs2_sbd *sdp, int silent, int undo)
@@ -311,7 +314,6 @@ static int init_sb(struct gfs2_sbd *sdp, int silent, int undo)
 	int error = 0;
 
 	if (undo) {
-		iput(sdp->sd_master_dir);
 		return 0;
 	}
 	
@@ -351,35 +353,24 @@ static int init_sb(struct gfs2_sbd *sdp, int silent, int undo)
 	sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
 
 	/* Get the root inode */
-	error = gfs2_lookup_root(sdp);
-	if (error) {
+	inode = gfs2_lookup_root(sdp, &sdp->sd_sb.sb_root_dir);
+	if (IS_ERR(inode)) {
+		error = PTR_ERR(inode);
 		fs_err(sdp, "can't read in root inode: %d\n", error);
 		goto out;
 	}
 
-	/* Get the root inode/dentry */
-	inode = sdp->sd_root_dir;
-	if (!inode) {
-		fs_err(sdp, "can't get root inode\n");
-		error = -ENOMEM;
-		goto out_rooti;
-	}
-
-	igrab(inode);
 	sb->s_root = d_alloc_root(inode);
 	if (!sb->s_root) {
 		fs_err(sdp, "can't get root dentry\n");
 		error = -ENOMEM;
-		goto out_rooti;
+		iput(inode);
 	}
 
 out:
 	gfs2_glock_dq_uninit(&sb_gh);
 
 	return error;
-out_rooti:
-	iput(sdp->sd_root_dir);
-	goto out;
 }
 
 static int init_journal(struct gfs2_sbd *sdp, int undo)
@@ -529,15 +520,18 @@ static int init_inodes(struct gfs2_sbd *sdp, int undo)
 {
 	int error = 0;
 	struct gfs2_inode *ip;
+	struct inode *inode;
 
 	if (undo)
 		goto fail_qinode;
 
-	error = gfs2_lookup_master_dir(sdp);
-	if (error) {
+	inode = gfs2_lookup_root(sdp, &sdp->sd_sb.sb_master_dir);
+	if (IS_ERR(inode)) {
+		error = PTR_ERR(inode);
 		fs_err(sdp, "can't read in master directory: %d\n", error);
 		goto fail;
 	}
+	sdp->sd_master_dir = inode;
 
 	error = init_journal(sdp, undo);
 	if (error)