orangefs: ensure the userspace component is unmounted if mount fails

If the mount is aborted after userspace has been asked to mount,
userspace must be told to unmount.

Ordinarily orangefs_kill_sb does the unmount.  However it cannot be
called if the superblock has not been set up.  This is a very narrow
window.

The NULL fs_id is not unmounted.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

fs/orangefs/orangefs-utils.c

@@ -523,41 +523,6 @@ int orangefs_flush_inode(struct inode *inode)
 	return ret;
 }
 
-int orangefs_unmount_sb(struct super_block *sb)
-{
-	int ret = -EINVAL;
-	struct orangefs_kernel_op_s *new_op = NULL;
-
-	gossip_debug(GOSSIP_UTILS_DEBUG,
-		     "orangefs_unmount_sb called on sb %p\n",
-		     sb);
-
-	new_op = op_alloc(ORANGEFS_VFS_OP_FS_UMOUNT);
-	if (!new_op)
-		return -ENOMEM;
-	new_op->upcall.req.fs_umount.id = ORANGEFS_SB(sb)->id;
-	new_op->upcall.req.fs_umount.fs_id = ORANGEFS_SB(sb)->fs_id;
-	strncpy(new_op->upcall.req.fs_umount.orangefs_config_server,
-		ORANGEFS_SB(sb)->devname,
-		ORANGEFS_MAX_SERVER_ADDR_LEN);
-
-	gossip_debug(GOSSIP_UTILS_DEBUG,
-		     "Attempting ORANGEFS Unmount via host %s\n",
-		     new_op->upcall.req.fs_umount.orangefs_config_server);
-
-	ret = service_operation(new_op, "orangefs_fs_umount", 0);
-
-	gossip_debug(GOSSIP_UTILS_DEBUG,
-		     "orangefs_unmount: got return value of %d\n", ret);
-	if (ret)
-		sb = ERR_PTR(ret);
-	else
-		ORANGEFS_SB(sb)->mount_pending = 1;
-
-	op_release(new_op);
-	return ret;
-}
-
 void orangefs_make_bad_inode(struct inode *inode)
 {
 	if (is_root_handle(inode)) {

fs/orangefs/super.c

@@ -376,6 +376,25 @@ static const struct export_operations orangefs_export_ops = {
 	.fh_to_dentry = orangefs_fh_to_dentry,
 };
 
+static int orangefs_unmount(int id, __s32 fs_id, const char *devname)
+{
+	struct orangefs_kernel_op_s *op;
+	int r;
+	op = op_alloc(ORANGEFS_VFS_OP_FS_UMOUNT);
+	if (!op)
+		return -ENOMEM;
+	op->upcall.req.fs_umount.id = id;
+	op->upcall.req.fs_umount.fs_id = fs_id;
+	strncpy(op->upcall.req.fs_umount.orangefs_config_server,
+	    devname, ORANGEFS_MAX_SERVER_ADDR_LEN);
+	r = service_operation(op, "orangefs_fs_umount", 0);
+	/* Not much to do about an error here. */
+	if (r)
+		gossip_err("orangefs_unmount: service_operation %d\n", r);
+	op_release(op);
+	return r;
+}
+
 static int orangefs_fill_sb(struct super_block *sb,
 		struct orangefs_fs_mount_response *fs_mount,
 		void *data, int silent)
@@ -484,6 +503,8 @@ struct dentry *orangefs_mount(struct file_system_type *fst,
 
 	if (IS_ERR(sb)) {
 		d = ERR_CAST(sb);
+		orangefs_unmount(new_op->downcall.resp.fs_mount.id,
+		    new_op->downcall.resp.fs_mount.fs_id, devname);
 		goto free_op;
 	}
 
@@ -539,6 +560,7 @@ struct dentry *orangefs_mount(struct file_system_type *fst,
 free_sb_and_op:
 	/* Will call orangefs_kill_sb with sb not in list. */
 	ORANGEFS_SB(sb)->no_list = 1;
+	/* ORANGEFS_VFS_OP_FS_UMOUNT is done by orangefs_kill_sb. */
 	deactivate_locked_super(sb);
 free_op:
 	gossip_err("orangefs_mount: mount request failed with %d\n", ret);
@@ -554,6 +576,7 @@ free_op:
 
 void orangefs_kill_sb(struct super_block *sb)
 {
+	int r;
 	gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_kill_sb: called\n");
 
 	/* provided sb cleanup */
@@ -563,7 +586,10 @@ void orangefs_kill_sb(struct super_block *sb)
 	 * issue the unmount to userspace to tell it to remove the
 	 * dynamic mount info it has for this superblock
 	 */
-	 orangefs_unmount_sb(sb);
+	r = orangefs_unmount(ORANGEFS_SB(sb)->id, ORANGEFS_SB(sb)->fs_id,
+	    ORANGEFS_SB(sb)->devname);
+	if (!r)
+		ORANGEFS_SB(sb)->mount_pending = 1;
 
 	if (!ORANGEFS_SB(sb)->no_list) {
 		/* remove the sb from our list of orangefs specific sb's */