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