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_from_kobj(struct kobject * kobj)27 static inline struct cma *cma_from_kobj(struct kobject *kobj)
28 {
29 return container_of(kobj, struct cma_kobject, kobj)->cma;
30 }
31
alloc_pages_success_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)32 static ssize_t alloc_pages_success_show(struct kobject *kobj,
33 struct kobj_attribute *attr, char *buf)
34 {
35 struct cma *cma = cma_from_kobj(kobj);
36
37 return sysfs_emit(buf, "%llu\n",
38 atomic64_read(&cma->nr_pages_succeeded));
39 }
40 CMA_ATTR_RO(alloc_pages_success);
41
alloc_pages_fail_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)42 static ssize_t alloc_pages_fail_show(struct kobject *kobj,
43 struct kobj_attribute *attr, char *buf)
44 {
45 struct cma *cma = cma_from_kobj(kobj);
46
47 return sysfs_emit(buf, "%llu\n", atomic64_read(&cma->nr_pages_failed));
48 }
49 CMA_ATTR_RO(alloc_pages_fail);
50
cma_kobj_release(struct kobject * kobj)51 static void cma_kobj_release(struct kobject *kobj)
52 {
53 struct cma *cma = cma_from_kobj(kobj);
54 struct cma_kobject *cma_kobj = cma->cma_kobj;
55
56 kfree(cma_kobj);
57 cma->cma_kobj = NULL;
58 }
59
60 static struct attribute *cma_attrs[] = {
61 &alloc_pages_success_attr.attr,
62 &alloc_pages_fail_attr.attr,
63 NULL,
64 };
65 ATTRIBUTE_GROUPS(cma);
66
67 static const struct kobj_type cma_ktype = {
68 .release = cma_kobj_release,
69 .sysfs_ops = &kobj_sysfs_ops,
70 .default_groups = cma_groups,
71 };
72
cma_sysfs_init(void)73 static int __init cma_sysfs_init(void)
74 {
75 struct kobject *cma_kobj_root;
76 struct cma_kobject *cma_kobj;
77 struct cma *cma;
78 int i, err;
79
80 cma_kobj_root = kobject_create_and_add("cma", mm_kobj);
81 if (!cma_kobj_root)
82 return -ENOMEM;
83
84 for (i = 0; i < cma_area_count; i++) {
85 cma_kobj = kzalloc(sizeof(*cma_kobj), GFP_KERNEL);
86 if (!cma_kobj) {
87 err = -ENOMEM;
88 goto out;
89 }
90
91 cma = &cma_areas[i];
92 cma->cma_kobj = cma_kobj;
93 cma_kobj->cma = cma;
94 err = kobject_init_and_add(&cma_kobj->kobj, &cma_ktype,
95 cma_kobj_root, "%s", cma->name);
96 if (err) {
97 kobject_put(&cma_kobj->kobj);
98 goto out;
99 }
100 }
101
102 return 0;
103 out:
104 while (--i >= 0) {
105 cma = &cma_areas[i];
106 kobject_put(&cma->cma_kobj->kobj);
107 }
108 kobject_put(cma_kobj_root);
109
110 return err;
111 }
112 subsys_initcall(cma_sysfs_init);
113
