1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * CMA SysFS Interface
4 *
5 * Copyright (c) 2021 Minchan Kim <minchan@kernel.org>
6 */
7
8 #include <linux/cma.h>
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11
12 #include "cma.h"
13
14 #define CMA_ATTR_RO(_name) \
15 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
16
cma_sysfs_account_success_pages(struct cma * cma,unsigned long nr_pages)17 void cma_sysfs_account_success_pages(struct cma *cma, unsigned long nr_pages)
18 {
19 atomic64_add(nr_pages, &cma->nr_pages_succeeded);
20 }
21
cma_sysfs_account_fail_pages(struct cma * cma,unsigned long nr_pages)22 void cma_sysfs_account_fail_pages(struct cma *cma, unsigned long nr_pages)
23 {
24 atomic64_add(nr_pages, &cma->nr_pages_failed);
25 }
26
cma_sysfs_account_release_pages(struct cma * cma,unsigned long nr_pages)27 void cma_sysfs_account_release_pages(struct cma *cma, unsigned long nr_pages)
28 {
29 atomic64_add(nr_pages, &cma->nr_pages_released);
30 }
31
cma_from_kobj(struct kobject * kobj)32 static inline struct cma *cma_from_kobj(struct kobject *kobj)
33 {
34 return container_of(kobj, struct cma_kobject, kobj)->cma;
35 }
36
alloc_pages_success_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)37 static ssize_t alloc_pages_success_show(struct kobject *kobj,
38 struct kobj_attribute *attr, char *buf)
39 {
40 struct cma *cma = cma_from_kobj(kobj);
41
42 return sysfs_emit(buf, "%llu\n",
43 atomic64_read(&cma->nr_pages_succeeded));
44 }
45 CMA_ATTR_RO(alloc_pages_success);
46
alloc_pages_fail_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)47 static ssize_t alloc_pages_fail_show(struct kobject *kobj,
48 struct kobj_attribute *attr, char *buf)
49 {
50 struct cma *cma = cma_from_kobj(kobj);
51
52 return sysfs_emit(buf, "%llu\n", atomic64_read(&cma->nr_pages_failed));
53 }
54 CMA_ATTR_RO(alloc_pages_fail);
55
release_pages_success_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)56 static ssize_t release_pages_success_show(struct kobject *kobj,
57 struct kobj_attribute *attr, char *buf)
58 {
59 struct cma *cma = cma_from_kobj(kobj);
60
61 return sysfs_emit(buf, "%llu\n", atomic64_read(&cma->nr_pages_released));
62 }
63 CMA_ATTR_RO(release_pages_success);
64
total_pages_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)65 static ssize_t total_pages_show(struct kobject *kobj,
66 struct kobj_attribute *attr, char *buf)
67 {
68 struct cma *cma = cma_from_kobj(kobj);
69
70 return sysfs_emit(buf, "%lu\n", cma->count);
71 }
72 CMA_ATTR_RO(total_pages);
73
available_pages_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)74 static ssize_t available_pages_show(struct kobject *kobj,
75 struct kobj_attribute *attr, char *buf)
76 {
77 struct cma *cma = cma_from_kobj(kobj);
78
79 return sysfs_emit(buf, "%lu\n", cma->available_count);
80 }
81 CMA_ATTR_RO(available_pages);
82
cma_kobj_release(struct kobject * kobj)83 static void cma_kobj_release(struct kobject *kobj)
84 {
85 struct cma *cma = cma_from_kobj(kobj);
86 struct cma_kobject *cma_kobj = cma->cma_kobj;
87
88 kfree(cma_kobj);
89 cma->cma_kobj = NULL;
90 }
91
92 static struct attribute *cma_attrs[] = {
93 &alloc_pages_success_attr.attr,
94 &alloc_pages_fail_attr.attr,
95 &release_pages_success_attr.attr,
96 &total_pages_attr.attr,
97 &available_pages_attr.attr,
98 NULL,
99 };
100 ATTRIBUTE_GROUPS(cma);
101
102 static const struct kobj_type cma_ktype = {
103 .release = cma_kobj_release,
104 .sysfs_ops = &kobj_sysfs_ops,
105 .default_groups = cma_groups,
106 };
107
cma_sysfs_init(void)108 static int __init cma_sysfs_init(void)
109 {
110 struct kobject *cma_kobj_root;
111 struct cma_kobject *cma_kobj;
112 struct cma *cma;
113 int i, err;
114
115 cma_kobj_root = kobject_create_and_add("cma", mm_kobj);
116 if (!cma_kobj_root)
117 return -ENOMEM;
118
119 for (i = 0; i < cma_area_count; i++) {
120 cma_kobj = kzalloc(sizeof(*cma_kobj), GFP_KERNEL);
121 if (!cma_kobj) {
122 err = -ENOMEM;
123 goto out;
124 }
125
126 cma = &cma_areas[i];
127 cma->cma_kobj = cma_kobj;
128 cma_kobj->cma = cma;
129 err = kobject_init_and_add(&cma_kobj->kobj, &cma_ktype,
130 cma_kobj_root, "%s", cma->name);
131 if (err) {
132 kobject_put(&cma_kobj->kobj);
133 goto out;
134 }
135 }
136
137 return 0;
138 out:
139 while (--i >= 0) {
140 cma = &cma_areas[i];
141 kobject_put(&cma->cma_kobj->kobj);
142 }
143 kobject_put(cma_kobj_root);
144
145 return err;
146 }
147 subsys_initcall(cma_sysfs_init);
148