[PATCH 5.4 2/3] btrfs: qgroup: return ENOTCONN instead of EINVAL when quotas are not enabled

[Harshvardhan Jha <harshvardhan.j.jha@oracle.com>]

From: Marcos Paulo de Souza <mpdesouza@suse.com>

[Upstream commit 8a36e408d40606e21cd4e2dd9601004a67b14868]

[PROBLEM]
qgroup create/remove code is currently returning EINVAL when the user
tries to create a qgroup on a subvolume without quota enabled. EINVAL is
already being used for too many error scenarios so that is hard to
depict what is the problem.

[FIX]
Currently scrub and balance code return -ENOTCONN when the user tries to
cancel/pause and no scrub or balance is currently running for the
desired subvolume. Do the same here by returning -ENOTCONN  when a user
tries to create/delete/assing/list a qgroup on a subvolume without quota
enabled.

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>
Signed-off-by: Harshvardhan Jha <harshvardhan.j.jha@oracle.com>
---
 fs/btrfs/qgroup.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 588abadcd784..7327636c9f26 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1354,7 +1354,7 @@ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
 	if (!fs_info->quota_root) {
-		ret = -EINVAL;
+		ret = -ENOTCONN;
 		goto out;
 	}
 	member = find_qgroup_rb(fs_info, src);
@@ -1413,7 +1413,7 @@ static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
 		return -ENOMEM;
 
 	if (!fs_info->quota_root) {
-		ret = -EINVAL;
+		ret = -ENOTCONN;
 		goto out;
 	}
 
@@ -1479,7 +1479,7 @@ int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
 	if (!fs_info->quota_root) {
-		ret = -EINVAL;
+		ret = -ENOTCONN;
 		goto out;
 	}
 	quota_root = fs_info->quota_root;
@@ -1513,7 +1513,7 @@ int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
 	if (!fs_info->quota_root) {
-		ret = -EINVAL;
+		ret = -ENOTCONN;
 		goto out;
 	}
 
@@ -1564,7 +1564,7 @@ int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
 	if (!fs_info->quota_root) {
-		ret = -EINVAL;
+		ret = -ENOTCONN;
 		goto out;
 	}
 
-- 
2.40.0