1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Common Primitives for DAMON Sysfs Interface
  4 *
  5 * Author: SeongJae Park <sj@kernel.org>
  6 */
  7
  8#include <linux/slab.h>
  9
 10#include "sysfs-common.h"
 11
 12DEFINE_MUTEX(damon_sysfs_lock);
 13
 14/*
 15 * unsigned long range directory
 16 */
 17
 18struct damon_sysfs_ul_range *damon_sysfs_ul_range_alloc(
 19		unsigned long min,
 20		unsigned long max)
 21{
 22	struct damon_sysfs_ul_range *range = kmalloc(sizeof(*range),
 23			GFP_KERNEL);
 24
 25	if (!range)
 26		return NULL;
 27	range->kobj = (struct kobject){};
 28	range->min = min;
 29	range->max = max;
 30
 31	return range;
 32}
 33
 34static ssize_t min_show(struct kobject *kobj, struct kobj_attribute *attr,
 35		char *buf)
 36{
 37	struct damon_sysfs_ul_range *range = container_of(kobj,
 38			struct damon_sysfs_ul_range, kobj);
 39
 40	return sysfs_emit(buf, "%lu\n", range->min);
 41}
 42
 43static ssize_t min_store(struct kobject *kobj, struct kobj_attribute *attr,
 44		const char *buf, size_t count)
 45{
 46	struct damon_sysfs_ul_range *range = container_of(kobj,
 47			struct damon_sysfs_ul_range, kobj);
 48	unsigned long min;
 49	int err;
 50
 51	err = kstrtoul(buf, 0, &min);
 52	if (err)
 53		return err;
 54
 55	range->min = min;
 56	return count;
 57}
 58
 59static ssize_t max_show(struct kobject *kobj, struct kobj_attribute *attr,
 60		char *buf)
 61{
 62	struct damon_sysfs_ul_range *range = container_of(kobj,
 63			struct damon_sysfs_ul_range, kobj);
 64
 65	return sysfs_emit(buf, "%lu\n", range->max);
 66}
 67
 68static ssize_t max_store(struct kobject *kobj, struct kobj_attribute *attr,
 69		const char *buf, size_t count)
 70{
 71	struct damon_sysfs_ul_range *range = container_of(kobj,
 72			struct damon_sysfs_ul_range, kobj);
 73	unsigned long max;
 74	int err;
 75
 76	err = kstrtoul(buf, 0, &max);
 77	if (err)
 78		return err;
 79
 80	range->max = max;
 81	return count;
 82}
 83
 84void damon_sysfs_ul_range_release(struct kobject *kobj)
 85{
 86	kfree(container_of(kobj, struct damon_sysfs_ul_range, kobj));
 87}
 88
 89static struct kobj_attribute damon_sysfs_ul_range_min_attr =
 90		__ATTR_RW_MODE(min, 0600);
 91
 92static struct kobj_attribute damon_sysfs_ul_range_max_attr =
 93		__ATTR_RW_MODE(max, 0600);
 94
 95static struct attribute *damon_sysfs_ul_range_attrs[] = {
 96	&damon_sysfs_ul_range_min_attr.attr,
 97	&damon_sysfs_ul_range_max_attr.attr,
 98	NULL,
 99};
100ATTRIBUTE_GROUPS(damon_sysfs_ul_range);
101
102const struct kobj_type damon_sysfs_ul_range_ktype = {
103	.release = damon_sysfs_ul_range_release,
104	.sysfs_ops = &kobj_sysfs_ops,
105	.default_groups = damon_sysfs_ul_range_groups,
106};
107