X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=include%2Flinux%2Fpid.h;h=c7980810eb09d96becad505f2f9349e9a9a56685;hb=9396d496d74587d46a74b93a8b6b41659d2daf2e;hp=1e0e4e3423a628a7983520762b7364038fbbe628;hpb=5e16e3f0e24dadb79b96b6134cd3303f0d42f0c5;p=linux-2.6-omap-h63xx.git

diff --git a/include/linux/pid.h b/include/linux/pid.h
index 1e0e4e3423a..c7980810eb0 100644
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -40,15 +40,28 @@ 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;
@@ -66,10 +79,9 @@ static inline struct pid *get_pid(struct pid *pid)
 	return pid;
 }
 
-extern void FASTCALL(put_pid(struct pid *pid));
-extern struct task_struct *FASTCALL(pid_task(struct pid *pid, enum pid_type));
-extern struct task_struct *FASTCALL(get_pid_task(struct pid *pid,
-						enum pid_type));
+extern void put_pid(struct pid *pid);
+extern struct task_struct *pid_task(struct pid *pid, enum pid_type);
+extern struct task_struct *get_pid_task(struct pid *pid, enum pid_type);
 
 extern struct pid *get_task_pid(struct task_struct *task, enum pid_type type);
 
@@ -77,35 +89,61 @@ extern struct pid *get_task_pid(struct task_struct *task, enum pid_type type);
  * attach_pid() and detach_pid() must be called with the tasklist_lock
  * write-held.
  */
-extern int FASTCALL(attach_pid(struct task_struct *task,
-				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));
+extern int attach_pid(struct task_struct *task, enum pid_type type,
+		      struct pid *pid);
+extern void detach_pid(struct task_struct *task, enum pid_type);
+extern void 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 *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 *);
+int next_pidmap(struct pid_namespace *pid_ns, int last);
+
+extern struct pid *alloc_pid(struct pid_namespace *ns);
+extern void free_pid(struct pid *pid);
 
-extern struct pid *alloc_pid(void);
-extern void FASTCALL(free_pid(struct pid *pid));
+/*
+ * 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 pid namespace of
+ *               current.
+ * 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);
+pid_t pid_vnr(struct pid *pid);
+
 #define do_each_pid_task(pid, type, task)				\
 	do {								\
 		struct hlist_node *pos___;				\
@@ -113,7 +151,13 @@ static inline pid_t pid_nr(struct pid *pid)
 			hlist_for_each_entry_rcu((task), pos___,	\
 				&pid->tasks[type], pids[type].node) {
 
+			/*
+			 * Both old and new leaders may be attached to
+			 * the same pid in the middle of de_thread().
+			 */
 #define while_each_pid_task(pid, type, task)				\
+				if (type == PIDTYPE_PID)		\
+					break;				\
 			}						\
 	} while (0)