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 atomic_long_t events;
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
50 /* misc.events */
51 struct cgroup_file events_file;
52
53 struct misc_res res[MISC_CG_RES_TYPES];
54 };
55
56 unsigned long misc_cg_res_total_usage(enum misc_res_type type);
57 int misc_cg_set_capacity(enum misc_res_type type, unsigned long capacity);
58 int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg,
59 unsigned long amount);
60 void misc_cg_uncharge(enum misc_res_type type, struct misc_cg *cg,
61 unsigned long amount);
62
63 /**
64 * css_misc() - Get misc cgroup from the css.
65 * @css: cgroup subsys state object.
66 *
67 * Context: Any context.
68 * Return:
69 * * %NULL - If @css is null.
70 * * struct misc_cg* - misc cgroup pointer of the passed css.
71 */
css_misc(struct cgroup_subsys_state * css)72 static inline struct misc_cg *css_misc(struct cgroup_subsys_state *css)
73 {
74 return css ? container_of(css, struct misc_cg, css) : NULL;
75 }
76
77 /*
78 * get_current_misc_cg() - Find and get the misc cgroup of the current task.
79 *
80 * Returned cgroup has its ref count increased by 1. Caller must call
81 * put_misc_cg() to return the reference.
82 *
83 * Return: Misc cgroup to which the current task belongs to.
84 */
get_current_misc_cg(void)85 static inline struct misc_cg *get_current_misc_cg(void)
86 {
87 return css_misc(task_get_css(current, misc_cgrp_id));
88 }
89
90 /*
91 * put_misc_cg() - Put the misc cgroup and reduce its ref count.
92 * @cg - cgroup to put.
93 */
put_misc_cg(struct misc_cg * cg)94 static inline void put_misc_cg(struct misc_cg *cg)
95 {
96 if (cg)
97 css_put(&cg->css);
98 }
99
100 #else /* !CONFIG_CGROUP_MISC */
101
misc_cg_res_total_usage(enum misc_res_type type)102 static inline unsigned long misc_cg_res_total_usage(enum misc_res_type type)
103 {
104 return 0;
105 }
106
misc_cg_set_capacity(enum misc_res_type type,unsigned long capacity)107 static inline int misc_cg_set_capacity(enum misc_res_type type,
108 unsigned long capacity)
109 {
110 return 0;
111 }
112
misc_cg_try_charge(enum misc_res_type type,struct misc_cg * cg,unsigned long amount)113 static inline int misc_cg_try_charge(enum misc_res_type type,
114 struct misc_cg *cg,
115 unsigned long amount)
116 {
117 return 0;
118 }
119
misc_cg_uncharge(enum misc_res_type type,struct misc_cg * cg,unsigned long amount)120 static inline void misc_cg_uncharge(enum misc_res_type type,
121 struct misc_cg *cg,
122 unsigned long amount)
123 {
124 }
125
get_current_misc_cg(void)126 static inline struct misc_cg *get_current_misc_cg(void)
127 {
128 return NULL;
129 }
130
put_misc_cg(struct misc_cg * cg)131 static inline void put_misc_cg(struct misc_cg *cg)
132 {
133 }
134
135 #endif /* CONFIG_CGROUP_MISC */
136 #endif /* _MISC_CGROUP_H_ */
137