From: Filipe Manana <fdmanana@suse.com>
Date: Thu, 26 Jun 2025 15:57:02 +0000 (+0100)
Subject: btrfs: qgroup: avoid memory allocation if qgroups are not enabled
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6633a416ed64aeb5c0a971d091d598b144739886;p=thirdparty%2Flinux.git

btrfs: qgroup: avoid memory allocation if qgroups are not enabled

At btrfs_qgroup_inherit() we allocate a qgroup record even if qgroups are
not enabled, which is unnecessary overhead and can result in subvolume
creation to fail with -ENOMEM, as create_subvol() calls this function.

Improve on this by making btrfs_qgroup_inherit() check if qgroups are
enabled earlier and return if they are not, avoiding the unnecessary
memory allocation and taking some locks.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index afc9a27071298..b83d9534adaed 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -3328,6 +3328,9 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
 	u32 level_size = 0;
 	u64 nums;
 
+	if (!btrfs_qgroup_enabled(fs_info))
+		return 0;
+
 	prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
 	if (!prealloc)
 		return -ENOMEM;
@@ -3351,8 +3354,6 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
 
 	if (!committing)
 		mutex_lock(&fs_info->qgroup_ioctl_lock);
-	if (!btrfs_qgroup_enabled(fs_info))
-		goto out;
 
 	quota_root = fs_info->quota_root;
 	if (!quota_root) {