| 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 | */ |
| 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 | */ |
| 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 | */ |
| 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 | |
| 102 | static inline unsigned long misc_cg_res_total_usage(enum misc_res_type type) |
| 103 | { |
| 104 | return 0; |
| 105 | } |
| 106 | |
| 107 | static inline int misc_cg_set_capacity(enum misc_res_type type, |
| 108 | unsigned long capacity) |
| 109 | { |
| 110 | return 0; |
| 111 | } |
| 112 | |
| 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 | |
| 120 | static inline void misc_cg_uncharge(enum misc_res_type type, |
| 121 | struct misc_cg *cg, |
| 122 | unsigned long amount) |
| 123 | { |
| 124 | } |
| 125 | |
| 126 | static inline struct misc_cg *get_current_misc_cg(void) |
| 127 | { |
| 128 | return NULL; |
| 129 | } |
| 130 | |
| 131 | static inline void put_misc_cg(struct misc_cg *cg) |
| 132 | { |
| 133 | } |
| 134 | |
| 135 | #endif /* CONFIG_CGROUP_MISC */ |
| 136 | #endif /* _MISC_CGROUP_H_ */ |