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 | |
17 | void cma_sysfs_account_success_pages(struct cma *cma, unsigned long nr_pages) |
18 | { |
19 | atomic64_add(i: nr_pages, v: &cma->nr_pages_succeeded); |
20 | } |
21 | |
22 | void cma_sysfs_account_fail_pages(struct cma *cma, unsigned long nr_pages) |
23 | { |
24 | atomic64_add(i: nr_pages, v: &cma->nr_pages_failed); |
25 | } |
26 | |
27 | static inline struct cma *cma_from_kobj(struct kobject *kobj) |
28 | { |
29 | return container_of(kobj, struct cma_kobject, kobj)->cma; |
30 | } |
31 | |
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, fmt: "%llu\n" , |
38 | atomic64_read(v: &cma->nr_pages_succeeded)); |
39 | } |
40 | CMA_ATTR_RO(alloc_pages_success); |
41 | |
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, fmt: "%llu\n" , atomic64_read(v: &cma->nr_pages_failed)); |
48 | } |
49 | CMA_ATTR_RO(alloc_pages_fail); |
50 | |
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(objp: 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 | |
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(name: "cma" , parent: mm_kobj); |
81 | if (!cma_kobj_root) |
82 | return -ENOMEM; |
83 | |
84 | for (i = 0; i < cma_area_count; i++) { |
85 | cma_kobj = kzalloc(size: 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(kobj: &cma_kobj->kobj, ktype: &cma_ktype, |
95 | parent: cma_kobj_root, fmt: "%s" , cma->name); |
96 | if (err) { |
97 | kobject_put(kobj: &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(kobj: &cma->cma_kobj->kobj); |
107 | } |
108 | kobject_put(kobj: cma_kobj_root); |
109 | |
110 | return err; |
111 | } |
112 | subsys_initcall(cma_sysfs_init); |
113 | |