1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _linux_POSIX_TIMERS_H
3#define _linux_POSIX_TIMERS_H
4
5#include <linux/spinlock.h>
6#include <linux/list.h>
7#include <linux/sched.h>
8#include <linux/timex.h>
9#include <linux/alarmtimer.h>
10
11struct siginfo;
12
13struct cpu_timer_list {
14 struct list_head entry;
15 u64 expires, incr;
16 struct task_struct *task;
17 int firing;
18};
19
20/*
21 * Bit fields within a clockid:
22 *
23 * The most significant 29 bits hold either a pid or a file descriptor.
24 *
25 * Bit 2 indicates whether a cpu clock refers to a thread or a process.
26 *
27 * Bits 1 and 0 give the type: PROF=0, VIRT=1, SCHED=2, or FD=3.
28 *
29 * A clockid is invalid if bits 2, 1, and 0 are all set.
30 */
31#define CPUCLOCK_PID(clock) ((pid_t) ~((clock) >> 3))
32#define CPUCLOCK_PERTHREAD(clock) \
33 (((clock) & (clockid_t) CPUCLOCK_PERTHREAD_MASK) != 0)
34
35#define CPUCLOCK_PERTHREAD_MASK 4
36#define CPUCLOCK_WHICH(clock) ((clock) & (clockid_t) CPUCLOCK_CLOCK_MASK)
37#define CPUCLOCK_CLOCK_MASK 3
38#define CPUCLOCK_PROF 0
39#define CPUCLOCK_VIRT 1
40#define CPUCLOCK_SCHED 2
41#define CPUCLOCK_MAX 3
42#define CLOCKFD CPUCLOCK_MAX
43#define CLOCKFD_MASK (CPUCLOCK_PERTHREAD_MASK|CPUCLOCK_CLOCK_MASK)
44
45static inline clockid_t make_process_cpuclock(const unsigned int pid,
46 const clockid_t clock)
47{
48 return ((~pid) << 3) | clock;
49}
50static inline clockid_t make_thread_cpuclock(const unsigned int tid,
51 const clockid_t clock)
52{
53 return make_process_cpuclock(tid, clock | CPUCLOCK_PERTHREAD_MASK);
54}
55
56static inline clockid_t fd_to_clockid(const int fd)
57{
58 return make_process_cpuclock((unsigned int) fd, CLOCKFD);
59}
60
61static inline int clockid_to_fd(const clockid_t clk)
62{
63 return ~(clk >> 3);
64}
65
66#define REQUEUE_PENDING 1
67
68/**
69 * struct k_itimer - POSIX.1b interval timer structure.
70 * @list: List head for binding the timer to signals->posix_timers
71 * @t_hash: Entry in the posix timer hash table
72 * @it_lock: Lock protecting the timer
73 * @kclock: Pointer to the k_clock struct handling this timer
74 * @it_clock: The posix timer clock id
75 * @it_id: The posix timer id for identifying the timer
76 * @it_active: Marker that timer is active
77 * @it_overrun: The overrun counter for pending signals
78 * @it_overrun_last: The overrun at the time of the last delivered signal
79 * @it_requeue_pending: Indicator that timer waits for being requeued on
80 * signal delivery
81 * @it_sigev_notify: The notify word of sigevent struct for signal delivery
82 * @it_interval: The interval for periodic timers
83 * @it_signal: Pointer to the creators signal struct
84 * @it_pid: The pid of the process/task targeted by the signal
85 * @it_process: The task to wakeup on clock_nanosleep (CPU timers)
86 * @sigq: Pointer to preallocated sigqueue
87 * @it: Union representing the various posix timer type
88 * internals. Also used for rcu freeing the timer.
89 */
90struct k_itimer {
91 struct list_head list;
92 struct hlist_node t_hash;
93 spinlock_t it_lock;
94 const struct k_clock *kclock;
95 clockid_t it_clock;
96 timer_t it_id;
97 int it_active;
98 s64 it_overrun;
99 s64 it_overrun_last;
100 int it_requeue_pending;
101 int it_sigev_notify;
102 ktime_t it_interval;
103 struct signal_struct *it_signal;
104 union {
105 struct pid *it_pid;
106 struct task_struct *it_process;
107 };
108 struct sigqueue *sigq;
109 union {
110 struct {
111 struct hrtimer timer;
112 } real;
113 struct cpu_timer_list cpu;
114 struct {
115 struct alarm alarmtimer;
116 } alarm;
117 struct rcu_head rcu;
118 } it;
119};
120
121void run_posix_cpu_timers(struct task_struct *task);
122void posix_cpu_timers_exit(struct task_struct *task);
123void posix_cpu_timers_exit_group(struct task_struct *task);
124void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx,
125 u64 *newval, u64 *oldval);
126
127void update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new);
128
129void posixtimer_rearm(struct siginfo *info);
130#endif
131