xref: /openbmc/linux/mm/damon/sysfs-common.c (revision 979ac5ef)
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 
12 DEFINE_MUTEX(damon_sysfs_lock);
13 
14 /*
15  * unsigned long range directory
16  */
17 
18 struct 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 
34 static 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 
43 static 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 
59 static 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 
68 static 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 
84 void damon_sysfs_ul_range_release(struct kobject *kobj)
85 {
86 	kfree(container_of(kobj, struct damon_sysfs_ul_range, kobj));
87 }
88 
89 static struct kobj_attribute damon_sysfs_ul_range_min_attr =
90 		__ATTR_RW_MODE(min, 0600);
91 
92 static struct kobj_attribute damon_sysfs_ul_range_max_attr =
93 		__ATTR_RW_MODE(max, 0600);
94 
95 static 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 };
100 ATTRIBUTE_GROUPS(damon_sysfs_ul_range);
101 
102 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 
108