Al Viro <viro@xxxxxxxxxxxxxxxxxx> writes:
> On Mon, Apr 04, 2022 at 09:41:36AM -0400, Gabriel Krisman Bertazi wrote:
>> In order to expose tmpfs statistics on sysfs, add the boilerplate code
>> to create the /sys/fs/tmpfs structure. As suggested on a previous
>> review, this uses the minor as the volume directory in /sys/fs/.
>>
>> This takes care of not exposing SB_NOUSER mounts. I don't think we have
>> a usecase for showing them and, since they don't appear elsewhere, they
>> might be confusing to users.
>>
>> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
>
>> +static void shmem_unregister_sysfs(struct super_block *sb)
>> +{
>> + struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
>> +
>> + kobject_del(&sbinfo->s_kobj);
>> + kobject_put(&sbinfo->s_kobj);
>> + wait_for_completion(&sbinfo->s_kobj_unregister);
>> +}
>
> If you embed kobject into something, you basically commit to
> having the lifetime rules maintained by that kobject...
Hi Viro,
The way I'm doing it seems to be a pattern used by at least Ext4, f2fs
and Btrfs. Is there a problem with embedding it in the superblock,
holding a reference and then waiting for completion when umounting the
fs?
--
Gabriel Krisman Bertazi
