On 12/03, Chao Yu wrote:
> Jaegeuk,
>
> Can you comment on this patch?
Waiting for use-case? :)
>
> On 2020/11/27 17:01, Chao Yu wrote:
> > Add a new directory 'stat' in path of /sys/fs/f2fs/<devname>/, later
> > we can add new readonly stat sysfs file into this directory, it will
> > make <devname> directory less mess.
> >
> > Signed-off-by: Chao Yu <yuch...@huawei.com>
> > ---
> > fs/f2fs/f2fs.h | 5 +++-
> > fs/f2fs/sysfs.c | 69 +++++++++++++++++++++++++++++++++++++++++++++----
> > 2 files changed, 68 insertions(+), 6 deletions(-)
> >
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 0d38f2135016..a20059dece46 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -1510,9 +1510,12 @@ struct f2fs_sb_info {
> > unsigned int node_io_flag;
> > /* For sysfs suppport */
> > - struct kobject s_kobj;
> > + struct kobject s_kobj; /* /sys/fs/f2fs/<devname> */
> > struct completion s_kobj_unregister;
> > + struct kobject s_stat_kobj; /* /sys/fs/f2fs/<devname>/stat
> > */
> > + struct completion s_stat_kobj_unregister;
> > +
> > /* For shrinker support */
> > struct list_head s_list;
> > int s_ndevs; /* number of devices */
> > diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> > index ec77ccfea923..8c63a6e61dfd 100644
> > --- a/fs/f2fs/sysfs.c
> > +++ b/fs/f2fs/sysfs.c
> > @@ -708,6 +708,11 @@ static struct attribute *f2fs_feat_attrs[] = {
> > };
> > ATTRIBUTE_GROUPS(f2fs_feat);
> > +static struct attribute *f2fs_stat_attrs[] = {
> > + NULL,
> > +};
> > +ATTRIBUTE_GROUPS(f2fs_stat);
> > +
> > static const struct sysfs_ops f2fs_attr_ops = {
> > .show = f2fs_attr_show,
> > .store = f2fs_attr_store,
> > @@ -736,6 +741,44 @@ static struct kobject f2fs_feat = {
> > .kset = &f2fs_kset,
> > };
> > +static ssize_t f2fs_stat_attr_show(struct kobject *kobj,
> > + struct attribute *attr, char *buf)
> > +{
> > + struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
> > + s_stat_kobj);
> > + struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
> > +
> > + return a->show ? a->show(a, sbi, buf) : 0;
> > +}
> > +
> > +static ssize_t f2fs_stat_attr_store(struct kobject *kobj, struct attribute
> > *attr,
> > + const char *buf, size_t len)
> > +{
> > + struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
> > + s_stat_kobj);
> > + struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
> > +
> > + return a->store ? a->store(a, sbi, buf, len) : 0;
> > +}
> > +
> > +static void f2fs_stat_kobj_release(struct kobject *kobj)
> > +{
> > + struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
> > + s_stat_kobj);
> > + complete(&sbi->s_stat_kobj_unregister);
> > +}
> > +
> > +static const struct sysfs_ops f2fs_stat_attr_ops = {
> > + .show = f2fs_stat_attr_show,
> > + .store = f2fs_stat_attr_store,
> > +};
> > +
> > +static struct kobj_type f2fs_stat_ktype = {
> > + .default_groups = f2fs_stat_groups,
> > + .sysfs_ops = &f2fs_stat_attr_ops,
> > + .release = f2fs_stat_kobj_release,
> > +};
> > +
> > static int __maybe_unused segment_info_seq_show(struct seq_file *seq,
> > void *offset)
> > {
> > @@ -942,11 +985,15 @@ int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
> > init_completion(&sbi->s_kobj_unregister);
> > err = kobject_init_and_add(&sbi->s_kobj, &f2fs_sb_ktype, NULL,
> > "%s", sb->s_id);
> > - if (err) {
> > - kobject_put(&sbi->s_kobj);
> > - wait_for_completion(&sbi->s_kobj_unregister);
> > - return err;
> > - }
> > + if (err)
> > + goto put_sb_kobj;
> > +
> > + sbi->s_stat_kobj.kset = &f2fs_kset;
> > + init_completion(&sbi->s_stat_kobj_unregister);
> > + err = kobject_init_and_add(&sbi->s_stat_kobj, &f2fs_stat_ktype,
> > + &sbi->s_kobj, "stat");
> > + if (err)
> > + goto put_stat_kobj;
> > if (f2fs_proc_root)
> > sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
> > @@ -962,6 +1009,13 @@ int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
> > victim_bits_seq_show, sb);
> > }
> > return 0;
> > +put_stat_kobj:
> > + kobject_put(&sbi->s_stat_kobj);
> > + wait_for_completion(&sbi->s_stat_kobj_unregister);
> > +put_sb_kobj:
> > + kobject_put(&sbi->s_kobj);
> > + wait_for_completion(&sbi->s_kobj_unregister);
> > + return err;
> > }
> > void f2fs_unregister_sysfs(struct f2fs_sb_info *sbi)
> > @@ -973,6 +1027,11 @@ void f2fs_unregister_sysfs(struct f2fs_sb_info *sbi)
> > remove_proc_entry("victim_bits", sbi->s_proc);
> > remove_proc_entry(sbi->sb->s_id, f2fs_proc_root);
> > }
> > +
> > + kobject_del(&sbi->s_stat_kobj);
> > + kobject_put(&sbi->s_stat_kobj);
> > + wait_for_completion(&sbi->s_stat_kobj_unregister);
> > +
> > kobject_del(&sbi->s_kobj);
> > kobject_put(&sbi->s_kobj);
> > wait_for_completion(&sbi->s_kobj_unregister);
> >
