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 * @events: Number of times, the resource limit exceeded.
35 */
36 struct misc_res {
37 u64 max;
38 atomic64_t usage;
39 atomic64_t events;
40 };
41
42 /**
43 * struct misc_cg - Miscellaneous controller's cgroup structure.
44 * @css: cgroup subsys state object.
45 * @events_file: Handle for the misc resources events file.
46 * @res: Array of misc resources usage in the cgroup.
47 */
48 struct misc_cg {
49 struct cgroup_subsys_state css;
50
51 /* misc.events */
52 struct cgroup_file events_file;
53
54 struct misc_res res[MISC_CG_RES_TYPES];
55 };
56
57 u64 misc_cg_res_total_usage(enum misc_res_type type);
58 int misc_cg_set_capacity(enum misc_res_type type, u64 capacity);
59 int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg, u64 amount);
60 void misc_cg_uncharge(enum misc_res_type type, struct misc_cg *cg, u64 amount);
61
62 /**
63 * css_misc() - Get misc cgroup from the css.
64 * @css: cgroup subsys state object.
65 *
66 * Context: Any context.
67 * Return:
68 * * %NULL - If @css is null.
69 * * struct misc_cg* - misc cgroup pointer of the passed css.
70 */
css_misc(struct cgroup_subsys_state * css)71 static inline struct misc_cg *css_misc(struct cgroup_subsys_state *css)
72 {
73 return css ? container_of(css, struct misc_cg, css) : NULL;
74 }
75
76 /*
77 * get_current_misc_cg() - Find and get the misc cgroup of the current task.
78 *
79 * Returned cgroup has its ref count increased by 1. Caller must call
80 * put_misc_cg() to return the reference.
81 *
82 * Return: Misc cgroup to which the current task belongs to.
83 */
get_current_misc_cg(void)84 static inline struct misc_cg *get_current_misc_cg(void)
85 {
86 return css_misc(task_get_css(current, misc_cgrp_id));
87 }
88
89 /*
90 * put_misc_cg() - Put the misc cgroup and reduce its ref count.
91 * @cg - cgroup to put.
92 */
put_misc_cg(struct misc_cg * cg)93 static inline void put_misc_cg(struct misc_cg *cg)
94 {
95 if (cg)
96 css_put(&cg->css);
97 }
98
99 #else /* !CONFIG_CGROUP_MISC */
100
misc_cg_res_total_usage(enum misc_res_type type)101 static inline u64 misc_cg_res_total_usage(enum misc_res_type type)
102 {
103 return 0;
104 }
105
misc_cg_set_capacity(enum misc_res_type type,u64 capacity)106 static inline int misc_cg_set_capacity(enum misc_res_type type, u64 capacity)
107 {
108 return 0;
109 }
110
misc_cg_try_charge(enum misc_res_type type,struct misc_cg * cg,u64 amount)111 static inline int misc_cg_try_charge(enum misc_res_type type,
112 struct misc_cg *cg,
113 u64 amount)
114 {
115 return 0;
116 }
117
misc_cg_uncharge(enum misc_res_type type,struct misc_cg * cg,u64 amount)118 static inline void misc_cg_uncharge(enum misc_res_type type,
119 struct misc_cg *cg,
120 u64 amount)
121 {
122 }
123
get_current_misc_cg(void)124 static inline struct misc_cg *get_current_misc_cg(void)
125 {
126 return NULL;
127 }
128
put_misc_cg(struct misc_cg * cg)129 static inline void put_misc_cg(struct misc_cg *cg)
130 {
131 }
132
133 #endif /* CONFIG_CGROUP_MISC */
134 #endif /* _MISC_CGROUP_H_ */
135