[ATM]: Convert struct class_device to struct device

[linux-2.6-omap-h63xx.git] / include / linux / pid.h

diff --git a/include/linux/pid.h b/include/linux/pid.h
index 4dec047b1837f1d7e365d1127dbbc68e4937d201..e29a900a84992f308ced20ed5ce4e9a4f2685f09 100644 (file)
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -40,17 +40,32 @@ enum pid_type
  * processes.
  */
 
-struct pid
-{
-       atomic_t count;
+
+/*
+ * struct upid is used to get the id of the struct pid, as it is
+ * seen in particular namespace. Later the struct pid is found with
+ * find_pid_ns() using the int nr and struct pid_namespace *ns.
+ */
+
+struct upid {
        /* Try to keep pid_chain in the same cacheline as nr for find_pid */
        int nr;
+       struct pid_namespace *ns;
        struct hlist_node pid_chain;
+};
+
+struct pid
+{
+       atomic_t count;
        /* lists of tasks that use this pid */
        struct hlist_head tasks[PIDTYPE_MAX];
        struct rcu_head rcu;
+       int level;
+       struct upid numbers[1];
 };
 
+extern struct pid init_struct_pid;
+
 struct pid_link
 {
        struct hlist_node node;
@@ -76,48 +91,67 @@ extern struct pid *get_task_pid(struct task_struct *task, enum pid_type type);
  * write-held.
  */
 extern int FASTCALL(attach_pid(struct task_struct *task,
-                               enum pid_type type, int nr));
-
+                               enum pid_type type, struct pid *pid));
 extern void FASTCALL(detach_pid(struct task_struct *task, enum pid_type));
 extern void FASTCALL(transfer_pid(struct task_struct *old,
                                  struct task_struct *new, enum pid_type));
 
+struct pid_namespace;
+extern struct pid_namespace init_pid_ns;
+
 /*
  * look up a PID in the hash table. Must be called with the tasklist_lock
  * or rcu_read_lock() held.
+ *
+ * find_pid_ns() finds the pid in the namespace specified
+ * find_pid() find the pid by its global id, i.e. in the init namespace
+ * find_vpid() finr the pid by its virtual id, i.e. in the current namespace
+ *
+ * see also find_task_by_pid() set in include/linux/sched.h
  */
-extern struct pid *FASTCALL(find_pid(int nr));
+extern struct pid *FASTCALL(find_pid_ns(int nr, struct pid_namespace *ns));
+extern struct pid *find_vpid(int nr);
+extern struct pid *find_pid(int nr);
 
 /*
  * Lookup a PID in the hash table, and return with it's count elevated.
  */
 extern struct pid *find_get_pid(int nr);
-extern struct pid *find_ge_pid(int nr);
+extern struct pid *find_ge_pid(int nr, struct pid_namespace *);
 
-extern struct pid *alloc_pid(void);
+extern struct pid *alloc_pid(struct pid_namespace *ns);
 extern void FASTCALL(free_pid(struct pid *pid));
+extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
+
+/*
+ * the helpers to get the pid's id seen from different namespaces
+ *
+ * pid_nr()    : global id, i.e. the id seen from the init namespace;
+ * pid_vnr()   : virtual id, i.e. the id seen from the namespace this pid
+ *               belongs to. this only makes sence when called in the
+ *               context of the task that belongs to the same namespace;
+ * pid_nr_ns() : id seen from the ns specified.
+ *
+ * see also task_xid_nr() etc in include/linux/sched.h
+ */
 
 static inline pid_t pid_nr(struct pid *pid)
 {
        pid_t nr = 0;
        if (pid)
-               nr = pid->nr;
+               nr = pid->numbers[0].nr;
        return nr;
 }
 
+pid_t pid_nr_ns(struct pid *pid, struct pid_namespace *ns);
 
-#define do_each_task_pid(who, type, task)                              \
-       do {                                                            \
-               struct hlist_node *pos___;                              \
-               struct pid *pid___ = find_pid(who);                     \
-               if (pid___ != NULL)                                     \
-                       hlist_for_each_entry_rcu((task), pos___,        \
-                               &pid___->tasks[type], pids[type].node) {
-
-#define while_each_task_pid(who, type, task)                           \
-                       }                                               \
-       } while (0)
-
+static inline pid_t pid_vnr(struct pid *pid)
+{
+       pid_t nr = 0;
+       if (pid)
+               nr = pid->numbers[pid->level].nr;
+       return nr;
+}
 
 #define do_each_pid_task(pid, type, task)                              \
        do {                                                            \