#include <linux/rwsem.h>
#include <linux/idr.h>
#include <linux/workqueue.h>
-#include <linux/xattr.h>
#include <linux/fs.h>
#include <linux/percpu-refcount.h>
#include <linux/seq_file.h>
+#include <linux/kernfs.h>
#ifdef CONFIG_CGROUPS
extern void cgroup_exit(struct task_struct *p, int run_callbacks);
extern int cgroupstats_build(struct cgroupstats *stats,
struct dentry *dentry);
-extern int cgroup_load_subsys(struct cgroup_subsys *ss);
-extern void cgroup_unload_subsys(struct cgroup_subsys *ss);
extern int proc_cgroup_show(struct seq_file *, void *);
-/*
- * Define the enumeration of all cgroup subsystems.
- *
- * We define ids for builtin subsystems and then modular ones.
- */
-#define SUBSYS(_x) _x ## _subsys_id,
+/* define the enumeration of all cgroup subsystems */
+#define SUBSYS(_x) _x ## _cgrp_id,
enum cgroup_subsys_id {
-#define IS_SUBSYS_ENABLED(option) IS_BUILTIN(option)
#include <linux/cgroup_subsys.h>
-#undef IS_SUBSYS_ENABLED
- CGROUP_BUILTIN_SUBSYS_COUNT,
-
- __CGROUP_SUBSYS_TEMP_PLACEHOLDER = CGROUP_BUILTIN_SUBSYS_COUNT - 1,
-
-#define IS_SUBSYS_ENABLED(option) IS_MODULE(option)
-#include <linux/cgroup_subsys.h>
-#undef IS_SUBSYS_ENABLED
CGROUP_SUBSYS_COUNT,
};
#undef SUBSYS
CGRP_SANE_BEHAVIOR,
};
-struct cgroup_name {
- struct rcu_head rcu_head;
- char name[];
-};
-
struct cgroup {
unsigned long flags; /* "unsigned long" so bitops work */
*
* The ID of the root cgroup is always 0, and a new cgroup
* will be assigned with a smallest available ID.
+ *
+ * Allocating/Removing ID must be protected by cgroup_mutex.
*/
int id;
/* the number of attached css's */
int nr_css;
+ atomic_t refcnt;
+
/*
* We link our 'sibling' struct into our parent's 'children'.
* Our children link their 'sibling' into our 'children'.
*/
struct list_head sibling; /* my parent's children */
struct list_head children; /* my children */
- struct list_head files; /* my files */
struct cgroup *parent; /* my parent */
- struct dentry *dentry; /* cgroup fs entry, RCU protected */
+ struct kernfs_node *kn; /* cgroup kernfs entry */
/*
* Monotonically increasing unique serial number which defines a
*/
u64 serial_nr;
- /*
- * This is a copy of dentry->d_name, and it's needed because
- * we can't use dentry->d_name in cgroup_path().
- *
- * You must acquire rcu_read_lock() to access cgrp->name, and
- * the only place that can change it is rename(), which is
- * protected by parent dir's i_mutex.
- *
- * Normally you should use cgroup_name() wrapper rather than
- * access it directly.
- */
- struct cgroup_name __rcu *name;
-
/* Private pointers for each registered subsystem */
struct cgroup_subsys_state __rcu *subsys[CGROUP_SUBSYS_COUNT];
/* For css percpu_ref killing and RCU-protected deletion */
struct rcu_head rcu_head;
struct work_struct destroy_work;
-
- /* directory xattrs */
- struct simple_xattrs xattrs;
};
#define MAX_CGROUP_ROOT_NAMELEN 64
* - "release_agent" and "notify_on_release" are removed.
* Replacement notification mechanism will be implemented.
*
+ * - "xattr" mount option is deprecated. kernfs always enables it.
+ *
* - cpuset: tasks will be kept in empty cpusets when hotplug happens
* and take masks of ancestors with non-empty cpus/mems, instead of
* being moved to an ancestor.
/*
* A cgroupfs_root represents the root of a cgroup hierarchy, and may be
- * associated with a superblock to form an active hierarchy. This is
+ * associated with a kernfs_root to form an active hierarchy. This is
* internal to cgroup core. Don't access directly from controllers.
*/
struct cgroupfs_root {
- struct super_block *sb;
+ struct kernfs_root *kf_root;
/* The bitmask of subsystems attached to this hierarchy */
unsigned long subsys_mask;
+ atomic_t refcnt;
+
/* Unique id for this hierarchy. */
int hierarchy_id;
struct list_head cgrp_links;
/*
- * Set of subsystem states, one for each subsystem. This array
- * is immutable after creation apart from the init_css_set
- * during subsystem registration (at boot time) and modular subsystem
- * loading/unloading.
+ * Set of subsystem states, one for each subsystem. This array is
+ * immutable after creation apart from the init_css_set during
+ * subsystem registration (at boot time).
*/
struct cgroup_subsys_state *subsys[CGROUP_SUBSYS_COUNT];
umode_t mode;
/*
- * If non-zero, defines the maximum length of string that can
- * be passed to write_string; defaults to 64
+ * The maximum length of string, excluding trailing nul, that can
+ * be passed to write_string. If < PAGE_SIZE-1, PAGE_SIZE-1 is
+ * assumed.
*/
size_t max_write_len;
unsigned int flags;
/*
- * The subsys this file belongs to. Initialized automatically
- * during registration. NULL for cgroup core files.
+ * Fields used for internal bookkeeping. Initialized automatically
+ * during registration.
*/
- struct cgroup_subsys *ss;
+ struct cgroup_subsys *ss; /* NULL for cgroup core files */
+ struct list_head node; /* anchored at ss->cfts */
+ struct kernfs_ops *kf_ops;
/*
* read_u64() is a shortcut for the common case of returning a
* kick type for multiplexing.
*/
int (*trigger)(struct cgroup_subsys_state *css, unsigned int event);
-};
-
-/*
- * cftype_sets describe cftypes belonging to a subsystem and are chained at
- * cgroup_subsys->cftsets. Each cftset points to an array of cftypes
- * terminated by zero length name.
- */
-struct cftype_set {
- struct list_head node; /* chained at subsys->cftsets */
- struct cftype *cfts;
-};
-
-/*
- * cgroupfs file entry, pointed to from leaf dentry->d_fsdata. Don't
- * access directly.
- */
-struct cfent {
- struct list_head node;
- struct dentry *dentry;
- struct cftype *type;
- struct cgroup_subsys_state *css;
-
- /* file xattrs */
- struct simple_xattrs xattrs;
-};
-/* seq_file->private points to the following, only ->priv is public */
-struct cgroup_open_file {
- struct cfent *cfe;
- void *priv;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lock_class_key lockdep_key;
+#endif
};
/*
return cgrp->root->flags & CGRP_ROOT_SANE_BEHAVIOR;
}
-/* Caller should hold rcu_read_lock() */
-static inline const char *cgroup_name(const struct cgroup *cgrp)
+/* returns ino associated with a cgroup, 0 indicates unmounted root */
+static inline ino_t cgroup_ino(struct cgroup *cgrp)
{
- return rcu_dereference(cgrp->name)->name;
+ if (cgrp->kn)
+ return cgrp->kn->ino;
+ else
+ return 0;
}
-static inline struct cgroup_subsys_state *seq_css(struct seq_file *seq)
+static inline struct cftype *seq_cft(struct seq_file *seq)
{
- struct cgroup_open_file *of = seq->private;
- return of->cfe->css;
+ struct kernfs_open_file *of = seq->private;
+
+ return of->kn->priv;
}
-static inline struct cftype *seq_cft(struct seq_file *seq)
+struct cgroup_subsys_state *seq_css(struct seq_file *seq);
+
+/*
+ * Name / path handling functions. All are thin wrappers around the kernfs
+ * counterparts and can be called under any context.
+ */
+
+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)
+{
+ return kernfs_path(cgrp->kn, buf, buflen);
+}
+
+static inline void pr_cont_cgroup_name(struct cgroup *cgrp)
+{
+ /* dummy_top doesn't have a kn associated */
+ if (cgrp->kn)
+ pr_cont_kernfs_name(cgrp->kn);
+ else
+ pr_cont("/");
+}
+
+static inline void pr_cont_cgroup_path(struct cgroup *cgrp)
{
- struct cgroup_open_file *of = seq->private;
- return of->cfe->type;
+ /* dummy_top doesn't have a kn associated */
+ if (cgrp->kn)
+ pr_cont_kernfs_path(cgrp->kn);
+ else
+ pr_cont("/");
}
+char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen);
+
int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
int cgroup_rm_cftypes(struct cftype *cfts);
bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor);
-int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen);
-int task_cgroup_path(struct task_struct *task, char *buf, size_t buflen);
-
int cgroup_task_count(const struct cgroup *cgrp);
/*
(task) = cgroup_taskset_next((tset))) \
if (!(skip_css) || \
cgroup_taskset_cur_css((tset), \
- (skip_css)->ss->subsys_id) != (skip_css))
+ (skip_css)->ss->id) != (skip_css))
/*
* Control Group subsystem type.
struct task_struct *task);
void (*bind)(struct cgroup_subsys_state *root_css);
- int subsys_id;
int disabled;
int early_init;
bool broken_hierarchy;
bool warned_broken_hierarchy;
+ /* the following two fields are initialized automtically during boot */
+ int id;
#define MAX_CGROUP_TYPE_NAMELEN 32
const char *name;
/* link to parent, protected by cgroup_lock() */
struct cgroupfs_root *root;
- /* list of cftype_sets */
- struct list_head cftsets;
+ /*
+ * List of cftypes. Each entry is the first entry of an array
+ * terminated by zero length name.
+ */
+ struct list_head cfts;
- /* base cftypes, automatically [de]registered with subsys itself */
+ /* base cftypes, automatically registered with subsys itself */
struct cftype *base_cftypes;
- struct cftype_set base_cftset;
-
- /* should be defined only by modular subsystems */
- struct module *module;
};
-#define SUBSYS(_x) extern struct cgroup_subsys _x ## _subsys;
-#define IS_SUBSYS_ENABLED(option) IS_BUILTIN(option)
+#define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys;
#include <linux/cgroup_subsys.h>
-#undef IS_SUBSYS_ENABLED
#undef SUBSYS
/**
int cgroup_attach_task_all(struct task_struct *from, struct task_struct *);
int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from);
-struct cgroup_subsys_state *css_from_dir(struct dentry *dentry,
- struct cgroup_subsys *ss);
+struct cgroup_subsys_state *css_tryget_from_dir(struct dentry *dentry,
+ struct cgroup_subsys *ss);
#else /* !CONFIG_CGROUPS */