btrfs: qgroup: remove one-time use variables for quota_root checks

Remove some variables that are set only to be checked later, and never
used.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/qgroup.c

@@ -1243,7 +1243,6 @@ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
 			      u64 dst)
 {
 	struct btrfs_fs_info *fs_info = trans->fs_info;
-	struct btrfs_root *quota_root;
 	struct btrfs_qgroup *parent;
 	struct btrfs_qgroup *member;
 	struct btrfs_qgroup_list *list;
@@ -1259,8 +1258,7 @@ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
 		return -ENOMEM;
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
-	quota_root = fs_info->quota_root;
-	if (!quota_root) {
+	if (!fs_info->quota_root) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -1307,7 +1305,6 @@ static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
 				 u64 dst)
 {
 	struct btrfs_fs_info *fs_info = trans->fs_info;
-	struct btrfs_root *quota_root;
 	struct btrfs_qgroup *parent;
 	struct btrfs_qgroup *member;
 	struct btrfs_qgroup_list *list;
@@ -1320,8 +1317,7 @@ static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
 	if (!tmp)
 		return -ENOMEM;
 
-	quota_root = fs_info->quota_root;
-	if (!quota_root) {
+	if (!fs_info->quota_root) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -1387,11 +1383,11 @@ int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
 	int ret = 0;
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
-	quota_root = fs_info->quota_root;
-	if (!quota_root) {
+	if (!fs_info->quota_root) {
 		ret = -EINVAL;
 		goto out;
 	}
+	quota_root = fs_info->quota_root;
 	qgroup = find_qgroup_rb(fs_info, qgroupid);
 	if (qgroup) {
 		ret = -EEXIST;
@@ -1416,14 +1412,12 @@ int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
 int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
 {
 	struct btrfs_fs_info *fs_info = trans->fs_info;
-	struct btrfs_root *quota_root;
 	struct btrfs_qgroup *qgroup;
 	struct btrfs_qgroup_list *list;
 	int ret = 0;
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
-	quota_root = fs_info->quota_root;
-	if (!quota_root) {
+	if (!fs_info->quota_root) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -1465,7 +1459,6 @@ int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
 		       struct btrfs_qgroup_limit *limit)
 {
 	struct btrfs_fs_info *fs_info = trans->fs_info;
-	struct btrfs_root *quota_root;
 	struct btrfs_qgroup *qgroup;
 	int ret = 0;
 	/* Sometimes we would want to clear the limit on this qgroup.
@@ -1475,8 +1468,7 @@ int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
 	const u64 CLEAR_VALUE = -1;
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
-	quota_root = fs_info->quota_root;
-	if (!quota_root) {
+	if (!fs_info->quota_root) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -2582,10 +2574,9 @@ int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
 int btrfs_run_qgroups(struct btrfs_trans_handle *trans)
 {
 	struct btrfs_fs_info *fs_info = trans->fs_info;
-	struct btrfs_root *quota_root = fs_info->quota_root;
 	int ret = 0;
 
-	if (!quota_root)
+	if (!fs_info->quota_root)
 		return ret;
 
 	spin_lock(&fs_info->qgroup_lock);
@@ -2879,7 +2870,6 @@ static bool qgroup_check_limits(struct btrfs_fs_info *fs_info,
 static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
 			  enum btrfs_qgroup_rsv_type type)
 {
-	struct btrfs_root *quota_root;
 	struct btrfs_qgroup *qgroup;
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 ref_root = root->root_key.objectid;
@@ -2898,8 +2888,7 @@ static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
 		enforce = false;
 
 	spin_lock(&fs_info->qgroup_lock);
-	quota_root = fs_info->quota_root;
-	if (!quota_root)
+	if (!fs_info->quota_root)
 		goto out;
 
 	qgroup = find_qgroup_rb(fs_info, ref_root);
@@ -2966,7 +2955,6 @@ void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
 			       u64 ref_root, u64 num_bytes,
 			       enum btrfs_qgroup_rsv_type type)
 {
-	struct btrfs_root *quota_root;
 	struct btrfs_qgroup *qgroup;
 	struct ulist_node *unode;
 	struct ulist_iterator uiter;
@@ -2984,8 +2972,7 @@ void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
 	}
 	spin_lock(&fs_info->qgroup_lock);
 
-	quota_root = fs_info->quota_root;
-	if (!quota_root)
+	if (!fs_info->quota_root)
 		goto out;
 
 	qgroup = find_qgroup_rb(fs_info, ref_root);
@@ -3685,7 +3672,6 @@ void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
 static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
 				int num_bytes)
 {
-	struct btrfs_root *quota_root = fs_info->quota_root;
 	struct btrfs_qgroup *qgroup;
 	struct ulist_node *unode;
 	struct ulist_iterator uiter;
@@ -3693,7 +3679,7 @@ static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
 
 	if (num_bytes == 0)
 		return;
-	if (!quota_root)
+	if (!fs_info->quota_root)
 		return;
 
 	spin_lock(&fs_info->qgroup_lock);