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 */ 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 */ 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 */ 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 */ 100 101 static inline u64 misc_cg_res_total_usage(enum misc_res_type type) 102 { 103 return 0; 104 } 105 106 static inline int misc_cg_set_capacity(enum misc_res_type type, u64 capacity) 107 { 108 return 0; 109 } 110 111 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 } 117 118 static inline void misc_cg_uncharge(enum misc_res_type type, 119 struct misc_cg *cg, 120 u64 amount) 121 { 122 } 123 124 static inline struct misc_cg *get_current_misc_cg(void) 125 { 126 return NULL; 127 } 128 129 static inline void put_misc_cg(struct misc_cg *cg) 130 { 131 } 132 133 #endif /* CONFIG_CGROUP_MISC */ 134 #endif /* _MISC_CGROUP_H_ */ 135