On Tue, 2021-11-09 at 10:54 +0800, Huang Jianan wrote:
> Add sysfs interface to configure erofs related parameters in the
> future.
[]
> diff --git a/fs/erofs/sysfs.c b/fs/erofs/sysfs.c
[]
> +static ssize_t erofs_attr_show(struct kobject *kobj,
> + struct attribute *attr, char *buf)
> +{
> + struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info,
> + s_kobj);
> + struct erofs_attr *a = container_of(attr, struct erofs_attr, attr);
> + unsigned char *ptr = __struct_ptr(sbi, a->struct_type, a->offset);
> +
> + switch (a->attr_id) {
> + case attr_feature:
> + return snprintf(buf, PAGE_SIZE, "supported\n");
> + case attr_pointer_ui:
> + if (!ptr)
> + return 0;
> + return snprintf(buf, PAGE_SIZE, "%u\n",
> + *((unsigned int *) ptr));
Prefer sysfs_emit over snprintf
case attr_feature:
return sysfs_emit(buf, "supported\n");
case attr_pointer_ui:
...
return sysfs_emit(buf, "%u\n", *(unsigned int *)ptr);
etc...
