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 * enum misc_res_type - Types of misc cgroup entries supported by the host.
13 */
14 enum misc_res_type {
15 #ifdef CONFIG_KVM_AMD_SEV
16 /** @MISC_CG_RES_SEV: AMD SEV ASIDs resource */
17 MISC_CG_RES_SEV,
18 /** @MISC_CG_RES_SEV_ES: AMD SEV-ES ASIDs resource */
19 MISC_CG_RES_SEV_ES,
20 #endif
21 /** @MISC_CG_RES_TYPES: count of enum misc_res_type constants */
22 MISC_CG_RES_TYPES
23 };
24
25 struct misc_cg;
26
27 #ifdef CONFIG_CGROUP_MISC
28
29 #include <linux/cgroup.h>
30
31 /**
32 * struct misc_res: Per cgroup per misc type resource
33 * @max: Maximum limit on the resource.
34 * @watermark: Historical maximum usage of the resource.
35 * @usage: Current usage of the resource.
36 * @events: Number of times, the resource limit exceeded.
37 */
38 struct misc_res {
39 u64 max;
40 atomic64_t watermark;
41 atomic64_t usage;
42 atomic64_t events;
43 atomic64_t events_local;
44 };
45
46 /**
47 * struct misc_cg - Miscellaneous controller's cgroup structure.
48 * @css: cgroup subsys state object.
49 * @events_file: Handle for the misc resources events file.
50 * @res: Array of misc resources usage in the cgroup.
51 */
52 struct misc_cg {
53 struct cgroup_subsys_state css;
54
55 /* misc.events */
56 struct cgroup_file events_file;
57 /* misc.events.local */
58 struct cgroup_file events_local_file;
59
60 struct misc_res res[MISC_CG_RES_TYPES];
61 };
62
63 u64 misc_cg_res_total_usage(enum misc_res_type type);
64 int misc_cg_set_capacity(enum misc_res_type type, u64 capacity);
65 int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg, u64 amount);
66 void misc_cg_uncharge(enum misc_res_type type, struct misc_cg *cg, u64 amount);
67
68 /**
69 * css_misc() - Get misc cgroup from the css.
70 * @css: cgroup subsys state object.
71 *
72 * Context: Any context.
73 * Return:
74 * * %NULL - If @css is null.
75 * * struct misc_cg* - misc cgroup pointer of the passed css.
76 */
css_misc(struct cgroup_subsys_state * css)77 static inline struct misc_cg *css_misc(struct cgroup_subsys_state *css)
78 {
79 return css ? container_of(css, struct misc_cg, css) : NULL;
80 }
81
82 /*
83 * get_current_misc_cg() - Find and get the misc cgroup of the current task.
84 *
85 * Returned cgroup has its ref count increased by 1. Caller must call
86 * put_misc_cg() to return the reference.
87 *
88 * Return: Misc cgroup to which the current task belongs to.
89 */
get_current_misc_cg(void)90 static inline struct misc_cg *get_current_misc_cg(void)
91 {
92 return css_misc(task_get_css(current, misc_cgrp_id));
93 }
94
95 /*
96 * put_misc_cg() - Put the misc cgroup and reduce its ref count.
97 * @cg - cgroup to put.
98 */
put_misc_cg(struct misc_cg * cg)99 static inline void put_misc_cg(struct misc_cg *cg)
100 {
101 if (cg)
102 css_put(&cg->css);
103 }
104
105 #else /* !CONFIG_CGROUP_MISC */
106
misc_cg_res_total_usage(enum misc_res_type type)107 static inline u64 misc_cg_res_total_usage(enum misc_res_type type)
108 {
109 return 0;
110 }
111
misc_cg_set_capacity(enum misc_res_type type,u64 capacity)112 static inline int misc_cg_set_capacity(enum misc_res_type type, u64 capacity)
113 {
114 return 0;
115 }
116
misc_cg_try_charge(enum misc_res_type type,struct misc_cg * cg,u64 amount)117 static inline int misc_cg_try_charge(enum misc_res_type type,
118 struct misc_cg *cg,
119 u64 amount)
120 {
121 return 0;
122 }
123
misc_cg_uncharge(enum misc_res_type type,struct misc_cg * cg,u64 amount)124 static inline void misc_cg_uncharge(enum misc_res_type type,
125 struct misc_cg *cg,
126 u64 amount)
127 {
128 }
129
get_current_misc_cg(void)130 static inline struct misc_cg *get_current_misc_cg(void)
131 {
132 return NULL;
133 }
134
put_misc_cg(struct misc_cg * cg)135 static inline void put_misc_cg(struct misc_cg *cg)
136 {
137 }
138
139 #endif /* CONFIG_CGROUP_MISC */
140 #endif /* _MISC_CGROUP_H_ */
141