1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Miscellaneous cgroup controller.
4 *
5 * Copyright 2020 Google LLC
6 * Author: Vipin Sharma <vipinsh@google.com>
7 */
8 #ifndef _MISC_CGROUP_H_
9 #define _MISC_CGROUP_H_
10
11 /**
12 * Types of misc cgroup entries supported by the host.
13 */
14 enum misc_res_type {
15 #ifdef CONFIG_KVM_AMD_SEV
16 /* AMD SEV ASIDs resource */
17 MISC_CG_RES_SEV,
18 /* AMD SEV-ES ASIDs resource */
19 MISC_CG_RES_SEV_ES,
20 #endif
21 MISC_CG_RES_TYPES
22 };
23
24 struct misc_cg;
25
26 #ifdef CONFIG_CGROUP_MISC
27
28 #include <linux/cgroup.h>
29
30 /**
31 * struct misc_res: Per cgroup per misc type resource
32 * @max: Maximum limit on the resource.
33 * @usage: Current usage of the resource.
34 * @failed: True if charged failed for the resource in a cgroup.
35 */
36 struct misc_res {
37 unsigned long max;
38 atomic_long_t usage;
39 bool failed;
40 };
41
42 /**
43 * struct misc_cg - Miscellaneous controller's cgroup structure.
44 * @css: cgroup subsys state object.
45 * @res: Array of misc resources usage in the cgroup.
46 */
47 struct misc_cg {
48 struct cgroup_subsys_state css;
49 struct misc_res res[MISC_CG_RES_TYPES];
50 };
51
52 unsigned long misc_cg_res_total_usage(enum misc_res_type type);
53 int misc_cg_set_capacity(enum misc_res_type type, unsigned long capacity);
54 int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg,
55 unsigned long amount);
56 void misc_cg_uncharge(enum misc_res_type type, struct misc_cg *cg,
57 unsigned long amount);
58
59 /**
60 * css_misc() - Get misc cgroup from the css.
61 * @css: cgroup subsys state object.
62 *
63 * Context: Any context.
64 * Return:
65 * * %NULL - If @css is null.
66 * * struct misc_cg* - misc cgroup pointer of the passed css.
67 */
css_misc(struct cgroup_subsys_state * css)68 static inline struct misc_cg *css_misc(struct cgroup_subsys_state *css)
69 {
70 return css ? container_of(css, struct misc_cg, css) : NULL;
71 }
72
73 /*
74 * get_current_misc_cg() - Find and get the misc cgroup of the current task.
75 *
76 * Returned cgroup has its ref count increased by 1. Caller must call
77 * put_misc_cg() to return the reference.
78 *
79 * Return: Misc cgroup to which the current task belongs to.
80 */
get_current_misc_cg(void)81 static inline struct misc_cg *get_current_misc_cg(void)
82 {
83 return css_misc(task_get_css(current, misc_cgrp_id));
84 }
85
86 /*
87 * put_misc_cg() - Put the misc cgroup and reduce its ref count.
88 * @cg - cgroup to put.
89 */
put_misc_cg(struct misc_cg * cg)90 static inline void put_misc_cg(struct misc_cg *cg)
91 {
92 if (cg)
93 css_put(&cg->css);
94 }
95
96 #else /* !CONFIG_CGROUP_MISC */
97
misc_cg_res_total_usage(enum misc_res_type type)98 static inline unsigned long misc_cg_res_total_usage(enum misc_res_type type)
99 {
100 return 0;
101 }
102
misc_cg_set_capacity(enum misc_res_type type,unsigned long capacity)103 static inline int misc_cg_set_capacity(enum misc_res_type type,
104 unsigned long capacity)
105 {
106 return 0;
107 }
108
misc_cg_try_charge(enum misc_res_type type,struct misc_cg * cg,unsigned long amount)109 static inline int misc_cg_try_charge(enum misc_res_type type,
110 struct misc_cg *cg,
111 unsigned long amount)
112 {
113 return 0;
114 }
115
misc_cg_uncharge(enum misc_res_type type,struct misc_cg * cg,unsigned long amount)116 static inline void misc_cg_uncharge(enum misc_res_type type,
117 struct misc_cg *cg,
118 unsigned long amount)
119 {
120 }
121
get_current_misc_cg(void)122 static inline struct misc_cg *get_current_misc_cg(void)
123 {
124 return NULL;
125 }
126
put_misc_cg(struct misc_cg * cg)127 static inline void put_misc_cg(struct misc_cg *cg)
128 {
129 }
130
131 #endif /* CONFIG_CGROUP_MISC */
132 #endif /* _MISC_CGROUP_H_ */
133
