1 files changed, 34 insertions, 17 deletions

diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index e155aa78d859..c98dd7cb7076 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -21,11 +21,13 @@
 struct cgroupfs_root;
 struct cgroup_subsys;
 struct inode;
+struct cgroup;
 
 extern int cgroup_init_early(void);
 extern int cgroup_init(void);
 extern void cgroup_init_smp(void);
 extern void cgroup_lock(void);
+extern bool cgroup_lock_live_group(struct cgroup *cgrp);
 extern void cgroup_unlock(void);
 extern void cgroup_fork(struct task_struct *p);
 extern void cgroup_fork_callbacks(struct task_struct *p);
@@ -205,50 +207,64 @@ struct cftype {
          * subsystem, followed by a period */
         char name[MAX_CFTYPE_NAME];
         int private;
-        int (*open) (struct inode *inode, struct file *file);
-        ssize_t (*read) (struct cgroup *cgrp, struct cftype *cft,
-                         struct file *file,
-                         char __user *buf, size_t nbytes, loff_t *ppos);
+
+        /*
+         * If non-zero, defines the maximum length of string that can
+         * be passed to write_string; defaults to 64
+         */
+        size_t max_write_len;
+
+        int (*open)(struct inode *inode, struct file *file);
+        ssize_t (*read)(struct cgroup *cgrp, struct cftype *cft,
+                        struct file *file,
+                        char __user *buf, size_t nbytes, loff_t *ppos);
         /*
          * read_u64() is a shortcut for the common case of returning a
          * single integer. Use it in place of read()
          */
-        u64 (*read_u64) (struct cgroup *cgrp, struct cftype *cft);
+        u64 (*read_u64)(struct cgroup *cgrp, struct cftype *cft);
         /*
          * read_s64() is a signed version of read_u64()
          */
-        s64 (*read_s64) (struct cgroup *cgrp, struct cftype *cft);
+        s64 (*read_s64)(struct cgroup *cgrp, struct cftype *cft);
         /*
          * read_map() is used for defining a map of key/value
          * pairs. It should call cb->fill(cb, key, value) for each
          * entry. The key/value pairs (and their ordering) should not
          * change between reboots.
          */
-        int (*read_map) (struct cgroup *cont, struct cftype *cft,
-                         struct cgroup_map_cb *cb);
+        int (*read_map)(struct cgroup *cont, struct cftype *cft,
+                        struct cgroup_map_cb *cb);
         /*
          * read_seq_string() is used for outputting a simple sequence
          * using seqfile.
          */
-        int (*read_seq_string) (struct cgroup *cont, struct cftype *cft,
-                         struct seq_file *m);
+        int (*read_seq_string)(struct cgroup *cont, struct cftype *cft,
+                               struct seq_file *m);
 
-        ssize_t (*write) (struct cgroup *cgrp, struct cftype *cft,
-                          struct file *file,
-                          const char __user *buf, size_t nbytes, loff_t *ppos);
+        ssize_t (*write)(struct cgroup *cgrp, struct cftype *cft,
+                         struct file *file,
+                         const char __user *buf, size_t nbytes, loff_t *ppos);
 
         /*
          * write_u64() is a shortcut for the common case of accepting
          * a single integer (as parsed by simple_strtoull) from
          * userspace. Use in place of write(); return 0 or error.
          */
-        int (*write_u64) (struct cgroup *cgrp, struct cftype *cft, u64 val);
+        int (*write_u64)(struct cgroup *cgrp, struct cftype *cft, u64 val);
         /*
          * write_s64() is a signed version of write_u64()
          */
-        int (*write_s64) (struct cgroup *cgrp, struct cftype *cft, s64 val);
+        int (*write_s64)(struct cgroup *cgrp, struct cftype *cft, s64 val);
 
         /*
+         * write_string() is passed a nul-terminated kernelspace
+         * buffer of maximum length determined by max_write_len.
+         * Returns 0 or -ve error code.
+         */
+        int (*write_string)(struct cgroup *cgrp, struct cftype *cft,
+                            const char *buffer);
+        /*
          * trigger() callback can be used to get some kick from the
          * userspace, when the actual string written is not important
          * at all. The private field can be used to determine the
@@ -256,7 +272,7 @@ struct cftype {
          */
         int (*trigger)(struct cgroup *cgrp, unsigned int event);
 
-        int (*release) (struct inode *inode, struct file *file);
+        int (*release)(struct inode *inode, struct file *file);
 };
 
 struct cgroup_scanner {
@@ -348,7 +364,8 @@ static inline struct cgroup* task_cgroup(struct task_struct *task,
         return task_subsys_state(task, subsys_id)->cgroup;
 }
 
-int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *ss);
+int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *ss,
+                                                        char *nodename);
 
 /* A cgroup_iter should be treated as an opaque object */
 struct cgroup_iter {