[PATCH V2 3/5] erofs: add 'domain_id' prefix when register sysfs

[Jia Zhu <zhujia.zj@xxxxxxxxxxxxx>]

In shared domain mount procedure, add 'domain_id' prefix to register
sysfs entry. Thus we could distinguish mounts that don't use shared
domain.

Signed-off-by: Jia Zhu <zhujia.zj@xxxxxxxxxxxxx>
---
 fs/erofs/sysfs.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/fs/erofs/sysfs.c b/fs/erofs/sysfs.c
index c1383e508bbe..c0031d7bd817 100644
--- a/fs/erofs/sysfs.c
+++ b/fs/erofs/sysfs.c
@@ -201,12 +201,21 @@ static struct kobject erofs_feat = {
 int erofs_register_sysfs(struct super_block *sb)
 {
 	struct erofs_sb_info *sbi = EROFS_SB(sb);
+	char *name = NULL;
 	int err;
 
+	if (erofs_is_fscache_mode(sb)) {
+		name = kasprintf(GFP_KERNEL, "%s%s%s", sbi->opt.domain_id ?
+				sbi->opt.domain_id : "", sbi->opt.domain_id ? "," : "",
+				sbi->opt.fsid);
+		if (!name)
+			return -ENOMEM;
+	}
 	sbi->s_kobj.kset = &erofs_root;
 	init_completion(&sbi->s_kobj_unregister);
 	err = kobject_init_and_add(&sbi->s_kobj, &erofs_sb_ktype, NULL, "%s",
-			erofs_is_fscache_mode(sb) ? sbi->opt.fsid : sb->s_id);
+			name ? name : sb->s_id);
+	kfree(name);
 	if (err)
 		goto put_sb_kobj;
 	return 0;
-- 
2.20.1