diff options
| author | Anand Jain <anand.jain@oracle.com> | 2023-10-04 23:00:27 +0800 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2023-10-12 16:44:18 +0200 |
| commit | f3623740068e548b7c6fdb42171c118189d0e03f (patch) | |
| tree | 5b457db14ab368023c0395c4375004974309860f /fs/btrfs/sysfs.c | |
| parent | ac6ea6a914ed477902ceed64e988a493b52c6c71 (diff) | |
btrfs: sysfs: show temp_fsid feature
This adds sysfs objects to indicate temp_fsid feature support and
its status.
/sys/fs/btrfs/features/temp_fsid
/sys/fs/btrfs/<UUID>/temp_fsid
For example:
Consider two cloned and mounted devices.
$ blkid /dev/sdc[1-2]
/dev/sdc1: UUID="509ad44b-ad2a-4a8a-bc8d-fe69db7220d5" ..
/dev/sdc2: UUID="509ad44b-ad2a-4a8a-bc8d-fe69db7220d5" ..
One gets actual fsid, and the other gets the temp_fsid when
mounted.
$ btrfs filesystem show -m
Label: none uuid: 509ad44b-ad2a-4a8a-bc8d-fe69db7220d5
Total devices 1 FS bytes used 54.14MiB
devid 1 size 300.00MiB used 144.00MiB path /dev/sdc1
Label: none uuid: 33bad74e-c91b-43a5-aef8-b3cab97ae63a
Total devices 1 FS bytes used 54.14MiB
devid 1 size 300.00MiB used 144.00MiB path /dev/sdc2
Their sysfs as below.
$ cat /sys/fs/btrfs/features/temp_fsid
0
$ cat /sys/fs/btrfs/509ad44b-ad2a-4a8a-bc8d-fe69db7220d5/temp_fsid
0
$ cat /sys/fs/btrfs/33bad74e-c91b-43a5-aef8-b3cab97ae63a/temp_fsid
1
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/sysfs.c')
| -rw-r--r-- | fs/btrfs/sysfs.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index 21ab8b9b62ce..e6b51fb3ddc1 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -425,6 +425,13 @@ static ssize_t acl_show(struct kobject *kobj, struct kobj_attribute *a, char *bu } BTRFS_ATTR(static_feature, acl, acl_show); +static ssize_t temp_fsid_supported_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + return sysfs_emit(buf, "0\n"); +} +BTRFS_ATTR(static_feature, temp_fsid, temp_fsid_supported_show); + /* * Features which only depend on kernel version. * @@ -438,6 +445,7 @@ static struct attribute *btrfs_supported_static_feature_attrs[] = { BTRFS_ATTR_PTR(static_feature, send_stream_version), BTRFS_ATTR_PTR(static_feature, supported_rescue_options), BTRFS_ATTR_PTR(static_feature, supported_sectorsizes), + BTRFS_ATTR_PTR(static_feature, temp_fsid), NULL }; @@ -1205,6 +1213,15 @@ static ssize_t btrfs_generation_show(struct kobject *kobj, } BTRFS_ATTR(, generation, btrfs_generation_show); +static ssize_t btrfs_temp_fsid_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + + return sysfs_emit(buf, "%d\n", fs_info->fs_devices->temp_fsid); +} +BTRFS_ATTR(, temp_fsid, btrfs_temp_fsid_show); + static const char * const btrfs_read_policy_name[] = { "pid" }; static ssize_t btrfs_read_policy_show(struct kobject *kobj, @@ -1307,6 +1324,7 @@ static const struct attribute *btrfs_attrs[] = { BTRFS_ATTR_PTR(, read_policy), BTRFS_ATTR_PTR(, bg_reclaim_threshold), BTRFS_ATTR_PTR(, commit_stats), + BTRFS_ATTR_PTR(, temp_fsid), NULL, }; |