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
gcma_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)65 static ssize_t gcma_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, "%d\n", cma->gcma);
71 }
72 CMA_ATTR_RO(gcma);
73
cma_kobj_release(struct kobject * kobj)74 static void cma_kobj_release(struct kobject *kobj)
75 {
76 struct cma *cma = cma_from_kobj(kobj);
77 struct cma_kobject *cma_kobj = cma->cma_kobj;
78
79 kfree(cma_kobj);
80 cma->cma_kobj = NULL;
81 }
82
83 static struct attribute *cma_attrs[] = {
84 &alloc_pages_success_attr.attr,
85 &alloc_pages_fail_attr.attr,
86 &release_pages_success_attr.attr,
87 &gcma_attr.attr,
88 NULL,
89 };
90 ATTRIBUTE_GROUPS(cma);
91
92 static const struct kobj_type cma_ktype = {
93 .release = cma_kobj_release,
94 .sysfs_ops = &kobj_sysfs_ops,
95 .default_groups = cma_groups,
96 };
97
cma_sysfs_init(void)98 static int __init cma_sysfs_init(void)
99 {
100 struct kobject *cma_kobj_root;
101 struct cma_kobject *cma_kobj;
102 struct cma *cma;
103 int i, err;
104
105 cma_kobj_root = kobject_create_and_add("cma", mm_kobj);
106 if (!cma_kobj_root)
107 return -ENOMEM;
108
109 for (i = 0; i < cma_area_count; i++) {
110 cma_kobj = kzalloc(sizeof(*cma_kobj), GFP_KERNEL);
111 if (!cma_kobj) {
112 err = -ENOMEM;
113 goto out;
114 }
115
116 cma = &cma_areas[i];
117 cma->cma_kobj = cma_kobj;
118 cma_kobj->cma = cma;
119 err = kobject_init_and_add(&cma_kobj->kobj, &cma_ktype,
120 cma_kobj_root, "%s", cma->name);
121 if (err) {
122 kobject_put(&cma_kobj->kobj);
123 goto out;
124 }
125 }
126
127 return 0;
128 out:
129 while (--i >= 0) {
130 cma = &cma_areas[i];
131 kobject_put(&cma->cma_kobj->kobj);
132 }
133 kobject_put(cma_kobj_root);
134
135 return err;
136 }
137 subsys_initcall(cma_sysfs_init);
138