diff options
Diffstat (limited to 'include/linux/cgroup.h')
-rw-r--r-- | include/linux/cgroup.h | 192 |
1 files changed, 175 insertions, 17 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 8607c937145f..ca47b5d42764 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -17,6 +17,11 @@ #include <linux/seq_file.h> #include <linux/kernfs.h> #include <linux/jump_label.h> +#include <linux/nsproxy.h> +#include <linux/types.h> +#include <linux/ns_common.h> +#include <linux/nsproxy.h> +#include <linux/user_namespace.h> #include <linux/cgroup-defs.h> @@ -81,7 +86,9 @@ struct cgroup_subsys_state *cgroup_get_e_css(struct cgroup *cgroup, struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry, struct cgroup_subsys *ss); -bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor); +struct cgroup *cgroup_get_from_path(const char *path); +struct cgroup *cgroup_get_from_fd(int fd); + int cgroup_attach_task_all(struct task_struct *from, struct task_struct *); int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from); @@ -90,18 +97,15 @@ int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts); int cgroup_rm_cftypes(struct cftype *cfts); void cgroup_file_notify(struct cgroup_file *cfile); -char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen); +int task_cgroup_path(struct task_struct *task, char *buf, size_t buflen); int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry); int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns, struct pid *pid, struct task_struct *tsk); void cgroup_fork(struct task_struct *p); -extern int cgroup_can_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]); -extern void cgroup_cancel_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]); -extern void cgroup_post_fork(struct task_struct *p, - void *old_ss_priv[CGROUP_CANFORK_COUNT]); +extern int cgroup_can_fork(struct task_struct *p); +extern void cgroup_cancel_fork(struct task_struct *p); +extern void cgroup_post_fork(struct task_struct *p); void cgroup_exit(struct task_struct *p); void cgroup_free(struct task_struct *p); @@ -384,6 +388,21 @@ static inline void css_put_many(struct cgroup_subsys_state *css, unsigned int n) percpu_ref_put_many(&css->refcnt, n); } +static inline void cgroup_get(struct cgroup *cgrp) +{ + css_get(&cgrp->self); +} + +static inline bool cgroup_tryget(struct cgroup *cgrp) +{ + return css_tryget(&cgrp->self); +} + +static inline void cgroup_put(struct cgroup *cgrp) +{ + css_put(&cgrp->self); +} + /** * task_css_set_check - obtain a task's css_set with extra access conditions * @task: the task to obtain css_set for @@ -497,6 +516,54 @@ static inline struct cgroup *task_cgroup(struct task_struct *task, return task_css(task, subsys_id)->cgroup; } +static inline struct cgroup *task_dfl_cgroup(struct task_struct *task) +{ + return task_css_set(task)->dfl_cgrp; +} + +static inline struct cgroup *cgroup_parent(struct cgroup *cgrp) +{ + struct cgroup_subsys_state *parent_css = cgrp->self.parent; + + if (parent_css) + return container_of(parent_css, struct cgroup, self); + return NULL; +} + +/** + * cgroup_is_descendant - test ancestry + * @cgrp: the cgroup to be tested + * @ancestor: possible ancestor of @cgrp + * + * Test whether @cgrp is a descendant of @ancestor. It also returns %true + * if @cgrp == @ancestor. This function is safe to call as long as @cgrp + * and @ancestor are accessible. + */ +static inline bool cgroup_is_descendant(struct cgroup *cgrp, + struct cgroup *ancestor) +{ + if (cgrp->root != ancestor->root || cgrp->level < ancestor->level) + return false; + return cgrp->ancestor_ids[ancestor->level] == ancestor->id; +} + +/** + * task_under_cgroup_hierarchy - test task's membership of cgroup ancestry + * @task: the task to be tested + * @ancestor: possible ancestor of @task's cgroup + * + * Tests whether @task's default cgroup hierarchy is a descendant of @ancestor. + * It follows all the same rules as cgroup_is_descendant, and only applies + * to the default hierarchy. + */ +static inline bool task_under_cgroup_hierarchy(struct task_struct *task, + struct cgroup *ancestor) +{ + struct css_set *cset = task_css_set(task); + + return cgroup_is_descendant(cset->dfl_cgrp, ancestor); +} + /* no synchronization, the result can only be used as a hint */ static inline bool cgroup_is_populated(struct cgroup *cgrp) { @@ -538,9 +605,9 @@ static inline int cgroup_name(struct cgroup *cgrp, char *buf, size_t buflen) return kernfs_name(cgrp->kn, buf, buflen); } -static inline char * __must_check cgroup_path(struct cgroup *cgrp, char *buf, - size_t buflen) +static inline int cgroup_path(struct cgroup *cgrp, char *buf, size_t buflen) { + return kernfs_path(cgrp->kn, buf, buflen); } @@ -576,6 +643,7 @@ static inline void cgroup_kthread_ready(void) #else /* !CONFIG_CGROUPS */ struct cgroup_subsys_state; +struct cgroup; static inline void css_put(struct cgroup_subsys_state *css) {} static inline int cgroup_attach_task_all(struct task_struct *from, @@ -584,21 +652,111 @@ static inline int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry) { return -EINVAL; } static inline void cgroup_fork(struct task_struct *p) {} -static inline int cgroup_can_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]) -{ return 0; } -static inline void cgroup_cancel_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]) {} -static inline void cgroup_post_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]) {} +static inline int cgroup_can_fork(struct task_struct *p) { return 0; } +static inline void cgroup_cancel_fork(struct task_struct *p) {} +static inline void cgroup_post_fork(struct task_struct *p) {} static inline void cgroup_exit(struct task_struct *p) {} static inline void cgroup_free(struct task_struct *p) {} static inline int cgroup_init_early(void) { return 0; } static inline int cgroup_init(void) { return 0; } + +static inline bool task_under_cgroup_hierarchy(struct task_struct *task, + struct cgroup *ancestor) +{ + return true; +} + static inline void cgroup_init_kthreadd(void) {} static inline void cgroup_kthread_ready(void) {} #endif /* !CONFIG_CGROUPS */ +/* + * sock->sk_cgrp_data handling. For more info, see sock_cgroup_data + * definition in cgroup-defs.h. + */ +#ifdef CONFIG_SOCK_CGROUP_DATA + +#if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID) +extern spinlock_t cgroup_sk_update_lock; +#endif + +void cgroup_sk_alloc_disable(void); +void cgroup_sk_alloc(struct sock_cgroup_data *skcd); +void cgroup_sk_clone(struct sock_cgroup_data *skcd); +void cgroup_sk_free(struct sock_cgroup_data *skcd); + +static inline struct cgroup *sock_cgroup_ptr(struct sock_cgroup_data *skcd) +{ +#if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID) + unsigned long v; + + /* + * @skcd->val is 64bit but the following is safe on 32bit too as we + * just need the lower ulong to be written and read atomically. + */ + v = READ_ONCE(skcd->val); + + if (v & 3) + return &cgrp_dfl_root.cgrp; + + return (struct cgroup *)(unsigned long)v ?: &cgrp_dfl_root.cgrp; +#else + return (struct cgroup *)(unsigned long)skcd->val; +#endif +} + +#else /* CONFIG_CGROUP_DATA */ + +static inline void cgroup_sk_alloc(struct sock_cgroup_data *skcd) {} +static inline void cgroup_sk_clone(struct sock_cgroup_data *skcd) {} +static inline void cgroup_sk_free(struct sock_cgroup_data *skcd) {} + +#endif /* CONFIG_CGROUP_DATA */ + +struct cgroup_namespace { + atomic_t count; + struct ns_common ns; + struct user_namespace *user_ns; + struct css_set *root_cset; +}; + +extern struct cgroup_namespace init_cgroup_ns; + +#ifdef CONFIG_CGROUPS + +void free_cgroup_ns(struct cgroup_namespace *ns); + +struct cgroup_namespace *copy_cgroup_ns(unsigned long flags, + struct user_namespace *user_ns, + struct cgroup_namespace *old_ns); + +int cgroup_path_ns(struct cgroup *cgrp, char *buf, size_t buflen, + struct cgroup_namespace *ns); + +#else /* !CONFIG_CGROUPS */ + +static inline void free_cgroup_ns(struct cgroup_namespace *ns) { } +static inline struct cgroup_namespace * +copy_cgroup_ns(unsigned long flags, struct user_namespace *user_ns, + struct cgroup_namespace *old_ns) +{ + return old_ns; +} + +#endif /* !CONFIG_CGROUPS */ + +static inline void get_cgroup_ns(struct cgroup_namespace *ns) +{ + if (ns) + atomic_inc(&ns->count); +} + +static inline void put_cgroup_ns(struct cgroup_namespace *ns) +{ + if (ns && atomic_dec_and_test(&ns->count)) + free_cgroup_ns(ns); +} + #endif /* _LINUX_CGROUP_H */ |