[PATCH v5 03/18] btrfs: expose quota mode via sysfs

Boris Burkov
2023-07-27T22:15:12Z

Add a new sysfs file
/sys/fs/btrfs/<uuid>/qgroups/mode
which prints out the mode qgroups is running in. The possible modes are
disabled, qgroup, and squota

Signed-off-by: Boris Burkov <boris@bur.io>
---
fs/btrfs/sysfs.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index b1d1ac25237b..e53614753391 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -2086,6 +2086,31 @@ static ssize_t qgroup_enabled_show(struct kobject *qgroups_kobj,
}
BTRFS_ATTR(qgroups, enabled, qgroup_enabled_show);

+static ssize_t qgroup_mode_show(struct kobject *qgroups_kobj,
+ struct kobj_attribute *a,
+ char *buf)
+{
+ struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
+ char *mode = "";
+
+ spin_lock(&fs_info->qgroup_lock);
+ switch (btrfs_qgroup_mode(fs_info)) {
+ case BTRFS_QGROUP_MODE_DISABLED:
+ mode = "disabled";
+ break;
+ case BTRFS_QGROUP_MODE_FULL:
+ mode = "qgroup";
+ break;
+ case BTRFS_QGROUP_MODE_SIMPLE:
+ mode = "squota";
+ break;
+ }
+ spin_unlock(&fs_info->qgroup_lock);
+
+ return sysfs_emit(buf, "%s\n", mode);
+}
+BTRFS_ATTR(qgroups, mode, qgroup_mode_show);
+
static ssize_t qgroup_inconsistent_show(struct kobject *qgroups_kobj,
struct kobj_attribute *a,
char *buf)
@@ -2148,6 +2173,7 @@ static struct attribute *qgroups_attrs[] = {
BTRFS_ATTR_PTR(qgroups, enabled),
BTRFS_ATTR_PTR(qgroups, inconsistent),
BTRFS_ATTR_PTR(qgroups, drop_subtree_threshold),
+ BTRFS_ATTR_PTR(qgroups, mode),
NULL
};
ATTRIBUTE_GROUPS(qgroups);
--
2.41.0