1#ifndef _LINUX_PID_H
2#define _LINUX_PID_H
3
4#include <linux/rcupdate.h>
5
6enum pid_type
7{
8 PIDTYPE_PID,
9 PIDTYPE_PGID,
10 PIDTYPE_SID,
11 PIDTYPE_MAX
12};
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50struct upid {
51
52 int nr;
53 struct pid_namespace *ns;
54 struct hlist_node pid_chain;
55};
56
57struct pid
58{
59 atomic_t count;
60 unsigned int level;
61
62 struct hlist_head tasks[PIDTYPE_MAX];
63 struct rcu_head rcu;
64 struct upid numbers[1];
65};
66
67extern struct pid init_struct_pid;
68
69struct pid_link
70{
71 struct hlist_node node;
72 struct pid *pid;
73};
74
75static inline struct pid *get_pid(struct pid *pid)
76{
77 if (pid)
78 atomic_inc(&pid->count);
79 return pid;
80}
81
82extern void put_pid(struct pid *pid);
83extern struct task_struct *pid_task(struct pid *pid, enum pid_type);
84extern struct task_struct *get_pid_task(struct pid *pid, enum pid_type);
85
86extern struct pid *get_task_pid(struct task_struct *task, enum pid_type type);
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92extern void attach_pid(struct task_struct *task, enum pid_type type,
93 struct pid *pid);
94extern void detach_pid(struct task_struct *task, enum pid_type);
95extern void change_pid(struct task_struct *task, enum pid_type,
96 struct pid *pid);
97extern void transfer_pid(struct task_struct *old, struct task_struct *new,
98 enum pid_type);
99
100struct pid_namespace;
101extern struct pid_namespace init_pid_ns;
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112extern struct pid *find_pid_ns(int nr, struct pid_namespace *ns);
113extern struct pid *find_vpid(int nr);
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118extern struct pid *find_get_pid(int nr);
119extern struct pid *find_ge_pid(int nr, struct pid_namespace *);
120int next_pidmap(struct pid_namespace *pid_ns, int last);
121
122extern struct pid *alloc_pid(struct pid_namespace *ns);
123extern void free_pid(struct pid *pid);
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135static inline struct pid_namespace *ns_of_pid(struct pid *pid)
136{
137 struct pid_namespace *ns = NULL;
138 if (pid)
139 ns = pid->numbers[pid->level].ns;
140 return ns;
141}
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154static inline pid_t pid_nr(struct pid *pid)
155{
156 pid_t nr = 0;
157 if (pid)
158 nr = pid->numbers[0].nr;
159 return nr;
160}
161
162pid_t pid_nr_ns(struct pid *pid, struct pid_namespace *ns);
163pid_t pid_vnr(struct pid *pid);
164
165#define do_each_pid_task(pid, type, task) \
166 do { \
167 struct hlist_node *pos___; \
168 if ((pid) != NULL) \
169 hlist_for_each_entry_rcu((task), pos___, \
170 &(pid)->tasks[type], pids[type].node) {
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176#define while_each_pid_task(pid, type, task) \
177 if (type == PIDTYPE_PID) \
178 break; \
179 } \
180 } while (0)
181
182#define do_each_pid_thread(pid, type, task) \
183 do_each_pid_task(pid, type, task) { \
184 struct task_struct *tg___ = task; \
185 do {
186
187#define while_each_pid_thread(pid, type, task) \
188 } while_each_thread(tg___, task); \
189 task = tg___; \
190 } while_each_pid_task(pid, type, task)
191#endif
192