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authorThomas Gleixner <tglx@linutronix.de>2014-06-22 12:06:40 +0200
committerThomas Gleixner <tglx@linutronix.de>2014-06-23 11:22:35 +0200
commit5cee964597260237dd2cabb3ec22bba0da24b25d (patch)
treef548efb4181a4cffb026adf43178e65330533e87 /kernel/posix-timers.c
parent58394271c610e9c65dd0165a1c1f6dec75dc5f3e (diff)
downloadlinux-5cee964597260237dd2cabb3ec22bba0da24b25d.tar.bz2
time/timers: Move all time(r) related files into kernel/time
Except for Kconfig.HZ. That needs a separate treatment. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/posix-timers.c')
-rw-r--r--kernel/posix-timers.c1121
1 files changed, 0 insertions, 1121 deletions
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
deleted file mode 100644
index 424c2d4265c9..000000000000
--- a/kernel/posix-timers.c
+++ /dev/null
@@ -1,1121 +0,0 @@
-/*
- * linux/kernel/posix-timers.c
- *
- *
- * 2002-10-15 Posix Clocks & timers
- * by George Anzinger george@mvista.com
- *
- * Copyright (C) 2002 2003 by MontaVista Software.
- *
- * 2004-06-01 Fix CLOCK_REALTIME clock/timer TIMER_ABSTIME bug.
- * Copyright (C) 2004 Boris Hu
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or (at
- * your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
-
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- * MontaVista Software | 1237 East Arques Avenue | Sunnyvale | CA 94085 | USA
- */
-
-/* These are all the functions necessary to implement
- * POSIX clocks & timers
- */
-#include <linux/mm.h>
-#include <linux/interrupt.h>
-#include <linux/slab.h>
-#include <linux/time.h>
-#include <linux/mutex.h>
-
-#include <asm/uaccess.h>
-#include <linux/list.h>
-#include <linux/init.h>
-#include <linux/compiler.h>
-#include <linux/hash.h>
-#include <linux/posix-clock.h>
-#include <linux/posix-timers.h>
-#include <linux/syscalls.h>
-#include <linux/wait.h>
-#include <linux/workqueue.h>
-#include <linux/export.h>
-#include <linux/hashtable.h>
-
-/*
- * Management arrays for POSIX timers. Timers are now kept in static hash table
- * with 512 entries.
- * Timer ids are allocated by local routine, which selects proper hash head by
- * key, constructed from current->signal address and per signal struct counter.
- * This keeps timer ids unique per process, but now they can intersect between
- * processes.
- */
-
-/*
- * Lets keep our timers in a slab cache :-)
- */
-static struct kmem_cache *posix_timers_cache;
-
-static DEFINE_HASHTABLE(posix_timers_hashtable, 9);
-static DEFINE_SPINLOCK(hash_lock);
-
-/*
- * we assume that the new SIGEV_THREAD_ID shares no bits with the other
- * SIGEV values. Here we put out an error if this assumption fails.
- */
-#if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
- ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
-#error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
-#endif
-
-/*
- * parisc wants ENOTSUP instead of EOPNOTSUPP
- */
-#ifndef ENOTSUP
-# define ENANOSLEEP_NOTSUP EOPNOTSUPP
-#else
-# define ENANOSLEEP_NOTSUP ENOTSUP
-#endif
-
-/*
- * The timer ID is turned into a timer address by idr_find().
- * Verifying a valid ID consists of:
- *
- * a) checking that idr_find() returns other than -1.
- * b) checking that the timer id matches the one in the timer itself.
- * c) that the timer owner is in the callers thread group.
- */
-
-/*
- * CLOCKs: The POSIX standard calls for a couple of clocks and allows us
- * to implement others. This structure defines the various
- * clocks.
- *
- * RESOLUTION: Clock resolution is used to round up timer and interval
- * times, NOT to report clock times, which are reported with as
- * much resolution as the system can muster. In some cases this
- * resolution may depend on the underlying clock hardware and
- * may not be quantifiable until run time, and only then is the
- * necessary code is written. The standard says we should say
- * something about this issue in the documentation...
- *
- * FUNCTIONS: The CLOCKs structure defines possible functions to
- * handle various clock functions.
- *
- * The standard POSIX timer management code assumes the
- * following: 1.) The k_itimer struct (sched.h) is used for
- * the timer. 2.) The list, it_lock, it_clock, it_id and
- * it_pid fields are not modified by timer code.
- *
- * Permissions: It is assumed that the clock_settime() function defined
- * for each clock will take care of permission checks. Some
- * clocks may be set able by any user (i.e. local process
- * clocks) others not. Currently the only set able clock we
- * have is CLOCK_REALTIME and its high res counter part, both of
- * which we beg off on and pass to do_sys_settimeofday().
- */
-
-static struct k_clock posix_clocks[MAX_CLOCKS];
-
-/*
- * These ones are defined below.
- */
-static int common_nsleep(const clockid_t, int flags, struct timespec *t,
- struct timespec __user *rmtp);
-static int common_timer_create(struct k_itimer *new_timer);
-static void common_timer_get(struct k_itimer *, struct itimerspec *);
-static int common_timer_set(struct k_itimer *, int,
- struct itimerspec *, struct itimerspec *);
-static int common_timer_del(struct k_itimer *timer);
-
-static enum hrtimer_restart posix_timer_fn(struct hrtimer *data);
-
-static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);
-
-#define lock_timer(tid, flags) \
-({ struct k_itimer *__timr; \
- __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags)); \
- __timr; \
-})
-
-static int hash(struct signal_struct *sig, unsigned int nr)
-{
- return hash_32(hash32_ptr(sig) ^ nr, HASH_BITS(posix_timers_hashtable));
-}
-
-static struct k_itimer *__posix_timers_find(struct hlist_head *head,
- struct signal_struct *sig,
- timer_t id)
-{
- struct k_itimer *timer;
-
- hlist_for_each_entry_rcu(timer, head, t_hash) {
- if ((timer->it_signal == sig) && (timer->it_id == id))
- return timer;
- }
- return NULL;
-}
-
-static struct k_itimer *posix_timer_by_id(timer_t id)
-{
- struct signal_struct *sig = current->signal;
- struct hlist_head *head = &posix_timers_hashtable[hash(sig, id)];
-
- return __posix_timers_find(head, sig, id);
-}
-
-static int posix_timer_add(struct k_itimer *timer)
-{
- struct signal_struct *sig = current->signal;
- int first_free_id = sig->posix_timer_id;
- struct hlist_head *head;
- int ret = -ENOENT;
-
- do {
- spin_lock(&hash_lock);
- head = &posix_timers_hashtable[hash(sig, sig->posix_timer_id)];
- if (!__posix_timers_find(head, sig, sig->posix_timer_id)) {
- hlist_add_head_rcu(&timer->t_hash, head);
- ret = sig->posix_timer_id;
- }
- if (++sig->posix_timer_id < 0)
- sig->posix_timer_id = 0;
- if ((sig->posix_timer_id == first_free_id) && (ret == -ENOENT))
- /* Loop over all possible ids completed */
- ret = -EAGAIN;
- spin_unlock(&hash_lock);
- } while (ret == -ENOENT);
- return ret;
-}
-
-static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
-{
- spin_unlock_irqrestore(&timr->it_lock, flags);
-}
-
-/* Get clock_realtime */
-static int posix_clock_realtime_get(clockid_t which_clock, struct timespec *tp)
-{
- ktime_get_real_ts(tp);
- return 0;
-}
-
-/* Set clock_realtime */
-static int posix_clock_realtime_set(const clockid_t which_clock,
- const struct timespec *tp)
-{
- return do_sys_settimeofday(tp, NULL);
-}
-
-static int posix_clock_realtime_adj(const clockid_t which_clock,
- struct timex *t)
-{
- return do_adjtimex(t);
-}
-
-/*
- * Get monotonic time for posix timers
- */
-static int posix_ktime_get_ts(clockid_t which_clock, struct timespec *tp)
-{
- ktime_get_ts(tp);
- return 0;
-}
-
-/*
- * Get monotonic-raw time for posix timers
- */
-static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp)
-{
- getrawmonotonic(tp);
- return 0;
-}
-
-
-static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec *tp)
-{
- *tp = current_kernel_time();
- return 0;
-}
-
-static int posix_get_monotonic_coarse(clockid_t which_clock,
- struct timespec *tp)
-{
- *tp = get_monotonic_coarse();
- return 0;
-}
-
-static int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp)
-{
- *tp = ktime_to_timespec(KTIME_LOW_RES);
- return 0;
-}
-
-static int posix_get_boottime(const clockid_t which_clock, struct timespec *tp)
-{
- get_monotonic_boottime(tp);
- return 0;
-}
-
-static int posix_get_tai(clockid_t which_clock, struct timespec *tp)
-{
- timekeeping_clocktai(tp);
- return 0;
-}
-
-/*
- * Initialize everything, well, just everything in Posix clocks/timers ;)
- */
-static __init int init_posix_timers(void)
-{
- struct k_clock clock_realtime = {
- .clock_getres = hrtimer_get_res,
- .clock_get = posix_clock_realtime_get,
- .clock_set = posix_clock_realtime_set,
- .clock_adj = posix_clock_realtime_adj,
- .nsleep = common_nsleep,
- .nsleep_restart = hrtimer_nanosleep_restart,
- .timer_create = common_timer_create,
- .timer_set = common_timer_set,
- .timer_get = common_timer_get,
- .timer_del = common_timer_del,
- };
- struct k_clock clock_monotonic = {
- .clock_getres = hrtimer_get_res,
- .clock_get = posix_ktime_get_ts,
- .nsleep = common_nsleep,
- .nsleep_restart = hrtimer_nanosleep_restart,
- .timer_create = common_timer_create,
- .timer_set = common_timer_set,
- .timer_get = common_timer_get,
- .timer_del = common_timer_del,
- };
- struct k_clock clock_monotonic_raw = {
- .clock_getres = hrtimer_get_res,
- .clock_get = posix_get_monotonic_raw,
- };
- struct k_clock clock_realtime_coarse = {
- .clock_getres = posix_get_coarse_res,
- .clock_get = posix_get_realtime_coarse,
- };
- struct k_clock clock_monotonic_coarse = {
- .clock_getres = posix_get_coarse_res,
- .clock_get = posix_get_monotonic_coarse,
- };
- struct k_clock clock_tai = {
- .clock_getres = hrtimer_get_res,
- .clock_get = posix_get_tai,
- .nsleep = common_nsleep,
- .nsleep_restart = hrtimer_nanosleep_restart,
- .timer_create = common_timer_create,
- .timer_set = common_timer_set,
- .timer_get = common_timer_get,
- .timer_del = common_timer_del,
- };
- struct k_clock clock_boottime = {
- .clock_getres = hrtimer_get_res,
- .clock_get = posix_get_boottime,
- .nsleep = common_nsleep,
- .nsleep_restart = hrtimer_nanosleep_restart,
- .timer_create = common_timer_create,
- .timer_set = common_timer_set,
- .timer_get = common_timer_get,
- .timer_del = common_timer_del,
- };
-
- posix_timers_register_clock(CLOCK_REALTIME, &clock_realtime);
- posix_timers_register_clock(CLOCK_MONOTONIC, &clock_monotonic);
- posix_timers_register_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw);
- posix_timers_register_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse);
- posix_timers_register_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse);
- posix_timers_register_clock(CLOCK_BOOTTIME, &clock_boottime);
- posix_timers_register_clock(CLOCK_TAI, &clock_tai);
-
- posix_timers_cache = kmem_cache_create("posix_timers_cache",
- sizeof (struct k_itimer), 0, SLAB_PANIC,
- NULL);
- return 0;
-}
-
-__initcall(init_posix_timers);
-
-static void schedule_next_timer(struct k_itimer *timr)
-{
- struct hrtimer *timer = &timr->it.real.timer;
-
- if (timr->it.real.interval.tv64 == 0)
- return;
-
- timr->it_overrun += (unsigned int) hrtimer_forward(timer,
- timer->base->get_time(),
- timr->it.real.interval);
-
- timr->it_overrun_last = timr->it_overrun;
- timr->it_overrun = -1;
- ++timr->it_requeue_pending;
- hrtimer_restart(timer);
-}
-
-/*
- * This function is exported for use by the signal deliver code. It is
- * called just prior to the info block being released and passes that
- * block to us. It's function is to update the overrun entry AND to
- * restart the timer. It should only be called if the timer is to be
- * restarted (i.e. we have flagged this in the sys_private entry of the
- * info block).
- *
- * To protect against the timer going away while the interrupt is queued,
- * we require that the it_requeue_pending flag be set.
- */
-void do_schedule_next_timer(struct siginfo *info)
-{
- struct k_itimer *timr;
- unsigned long flags;
-
- timr = lock_timer(info->si_tid, &flags);
-
- if (timr && timr->it_requeue_pending == info->si_sys_private) {
- if (timr->it_clock < 0)
- posix_cpu_timer_schedule(timr);
- else
- schedule_next_timer(timr);
-
- info->si_overrun += timr->it_overrun_last;
- }
-
- if (timr)
- unlock_timer(timr, flags);
-}
-
-int posix_timer_event(struct k_itimer *timr, int si_private)
-{
- struct task_struct *task;
- int shared, ret = -1;
- /*
- * FIXME: if ->sigq is queued we can race with
- * dequeue_signal()->do_schedule_next_timer().
- *
- * If dequeue_signal() sees the "right" value of
- * si_sys_private it calls do_schedule_next_timer().
- * We re-queue ->sigq and drop ->it_lock().
- * do_schedule_next_timer() locks the timer
- * and re-schedules it while ->sigq is pending.
- * Not really bad, but not that we want.
- */
- timr->sigq->info.si_sys_private = si_private;
-
- rcu_read_lock();
- task = pid_task(timr->it_pid, PIDTYPE_PID);
- if (task) {
- shared = !(timr->it_sigev_notify & SIGEV_THREAD_ID);
- ret = send_sigqueue(timr->sigq, task, shared);
- }
- rcu_read_unlock();
- /* If we failed to send the signal the timer stops. */
- return ret > 0;
-}
-EXPORT_SYMBOL_GPL(posix_timer_event);
-
-/*
- * This function gets called when a POSIX.1b interval timer expires. It
- * is used as a callback from the kernel internal timer. The
- * run_timer_list code ALWAYS calls with interrupts on.
-
- * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
- */
-static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
-{
- struct k_itimer *timr;
- unsigned long flags;
- int si_private = 0;
- enum hrtimer_restart ret = HRTIMER_NORESTART;
-
- timr = container_of(timer, struct k_itimer, it.real.timer);
- spin_lock_irqsave(&timr->it_lock, flags);
-
- if (timr->it.real.interval.tv64 != 0)
- si_private = ++timr->it_requeue_pending;
-
- if (posix_timer_event(timr, si_private)) {
- /*
- * signal was not sent because of sig_ignor
- * we will not get a call back to restart it AND
- * it should be restarted.
- */
- if (timr->it.real.interval.tv64 != 0) {
- ktime_t now = hrtimer_cb_get_time(timer);
-
- /*
- * FIXME: What we really want, is to stop this
- * timer completely and restart it in case the
- * SIG_IGN is removed. This is a non trivial
- * change which involves sighand locking
- * (sigh !), which we don't want to do late in
- * the release cycle.
- *
- * For now we just let timers with an interval
- * less than a jiffie expire every jiffie to
- * avoid softirq starvation in case of SIG_IGN
- * and a very small interval, which would put
- * the timer right back on the softirq pending
- * list. By moving now ahead of time we trick
- * hrtimer_forward() to expire the timer
- * later, while we still maintain the overrun
- * accuracy, but have some inconsistency in
- * the timer_gettime() case. This is at least
- * better than a starved softirq. A more
- * complex fix which solves also another related
- * inconsistency is already in the pipeline.
- */
-#ifdef CONFIG_HIGH_RES_TIMERS
- {
- ktime_t kj = ktime_set(0, NSEC_PER_SEC / HZ);
-
- if (timr->it.real.interval.tv64 < kj.tv64)
- now = ktime_add(now, kj);
- }
-#endif
- timr->it_overrun += (unsigned int)
- hrtimer_forward(timer, now,
- timr->it.real.interval);
- ret = HRTIMER_RESTART;
- ++timr->it_requeue_pending;
- }
- }
-
- unlock_timer(timr, flags);
- return ret;
-}
-
-static struct pid *good_sigevent(sigevent_t * event)
-{
- struct task_struct *rtn = current->group_leader;
-
- if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
- (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
- !same_thread_group(rtn, current) ||
- (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
- return NULL;
-
- if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
- ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
- return NULL;
-
- return task_pid(rtn);
-}
-
-void posix_timers_register_clock(const clockid_t clock_id,
- struct k_clock *new_clock)
-{
- if ((unsigned) clock_id >= MAX_CLOCKS) {
- printk(KERN_WARNING "POSIX clock register failed for clock_id %d\n",
- clock_id);
- return;
- }
-
- if (!new_clock->clock_get) {
- printk(KERN_WARNING "POSIX clock id %d lacks clock_get()\n",
- clock_id);
- return;
- }
- if (!new_clock->clock_getres) {
- printk(KERN_WARNING "POSIX clock id %d lacks clock_getres()\n",
- clock_id);
- return;
- }
-
- posix_clocks[clock_id] = *new_clock;
-}
-EXPORT_SYMBOL_GPL(posix_timers_register_clock);
-
-static struct k_itimer * alloc_posix_timer(void)
-{
- struct k_itimer *tmr;
- tmr = kmem_cache_zalloc(posix_timers_cache, GFP_KERNEL);
- if (!tmr)
- return tmr;
- if (unlikely(!(tmr->sigq = sigqueue_alloc()))) {
- kmem_cache_free(posix_timers_cache, tmr);
- return NULL;
- }
- memset(&tmr->sigq->info, 0, sizeof(siginfo_t));
- return tmr;
-}
-
-static void k_itimer_rcu_free(struct rcu_head *head)
-{
- struct k_itimer *tmr = container_of(head, struct k_itimer, it.rcu);
-
- kmem_cache_free(posix_timers_cache, tmr);
-}
-
-#define IT_ID_SET 1
-#define IT_ID_NOT_SET 0
-static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
-{
- if (it_id_set) {
- unsigned long flags;
- spin_lock_irqsave(&hash_lock, flags);
- hlist_del_rcu(&tmr->t_hash);
- spin_unlock_irqrestore(&hash_lock, flags);
- }
- put_pid(tmr->it_pid);
- sigqueue_free(tmr->sigq);
- call_rcu(&tmr->it.rcu, k_itimer_rcu_free);
-}
-
-static struct k_clock *clockid_to_kclock(const clockid_t id)
-{
- if (id < 0)
- return (id & CLOCKFD_MASK) == CLOCKFD ?
- &clock_posix_dynamic : &clock_posix_cpu;
-
- if (id >= MAX_CLOCKS || !posix_clocks[id].clock_getres)
- return NULL;
- return &posix_clocks[id];
-}
-
-static int common_timer_create(struct k_itimer *new_timer)
-{
- hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
- return 0;
-}
-
-/* Create a POSIX.1b interval timer. */
-
-SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
- struct sigevent __user *, timer_event_spec,
- timer_t __user *, created_timer_id)
-{
- struct k_clock *kc = clockid_to_kclock(which_clock);
- struct k_itimer *new_timer;
- int error, new_timer_id;
- sigevent_t event;
- int it_id_set = IT_ID_NOT_SET;
-
- if (!kc)
- return -EINVAL;
- if (!kc->timer_create)
- return -EOPNOTSUPP;
-
- new_timer = alloc_posix_timer();
- if (unlikely(!new_timer))
- return -EAGAIN;
-
- spin_lock_init(&new_timer->it_lock);
- new_timer_id = posix_timer_add(new_timer);
- if (new_timer_id < 0) {
- error = new_timer_id;
- goto out;
- }
-
- it_id_set = IT_ID_SET;
- new_timer->it_id = (timer_t) new_timer_id;
- new_timer->it_clock = which_clock;
- new_timer->it_overrun = -1;
-
- if (timer_event_spec) {
- if (copy_from_user(&event, timer_event_spec, sizeof (event))) {
- error = -EFAULT;
- goto out;
- }
- rcu_read_lock();
- new_timer->it_pid = get_pid(good_sigevent(&event));
- rcu_read_unlock();
- if (!new_timer->it_pid) {
- error = -EINVAL;
- goto out;
- }
- } else {
- event.sigev_notify = SIGEV_SIGNAL;
- event.sigev_signo = SIGALRM;
- event.sigev_value.sival_int = new_timer->it_id;
- new_timer->it_pid = get_pid(task_tgid(current));
- }
-
- new_timer->it_sigev_notify = event.sigev_notify;
- new_timer->sigq->info.si_signo = event.sigev_signo;
- new_timer->sigq->info.si_value = event.sigev_value;
- new_timer->sigq->info.si_tid = new_timer->it_id;
- new_timer->sigq->info.si_code = SI_TIMER;
-
- if (copy_to_user(created_timer_id,
- &new_timer_id, sizeof (new_timer_id))) {
- error = -EFAULT;
- goto out;
- }
-
- error = kc->timer_create(new_timer);
- if (error)
- goto out;
-
- spin_lock_irq(&current->sighand->siglock);
- new_timer->it_signal = current->signal;
- list_add(&new_timer->list, &current->signal->posix_timers);
- spin_unlock_irq(&current->sighand->siglock);
-
- return 0;
- /*
- * In the case of the timer belonging to another task, after
- * the task is unlocked, the timer is owned by the other task
- * and may cease to exist at any time. Don't use or modify
- * new_timer after the unlock call.
- */
-out:
- release_posix_timer(new_timer, it_id_set);
- return error;
-}
-
-/*
- * Locking issues: We need to protect the result of the id look up until
- * we get the timer locked down so it is not deleted under us. The
- * removal is done under the idr spinlock so we use that here to bridge
- * the find to the timer lock. To avoid a dead lock, the timer id MUST
- * be release with out holding the timer lock.
- */
-static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
-{
- struct k_itimer *timr;
-
- /*
- * timer_t could be any type >= int and we want to make sure any
- * @timer_id outside positive int range fails lookup.
- */
- if ((unsigned long long)timer_id > INT_MAX)
- return NULL;
-
- rcu_read_lock();
- timr = posix_timer_by_id(timer_id);
- if (timr) {
- spin_lock_irqsave(&timr->it_lock, *flags);
- if (timr->it_signal == current->signal) {
- rcu_read_unlock();
- return timr;
- }
- spin_unlock_irqrestore(&timr->it_lock, *flags);
- }
- rcu_read_unlock();
-
- return NULL;
-}
-
-/*
- * Get the time remaining on a POSIX.1b interval timer. This function
- * is ALWAYS called with spin_lock_irq on the timer, thus it must not
- * mess with irq.
- *
- * We have a couple of messes to clean up here. First there is the case
- * of a timer that has a requeue pending. These timers should appear to
- * be in the timer list with an expiry as if we were to requeue them
- * now.
- *
- * The second issue is the SIGEV_NONE timer which may be active but is
- * not really ever put in the timer list (to save system resources).
- * This timer may be expired, and if so, we will do it here. Otherwise
- * it is the same as a requeue pending timer WRT to what we should
- * report.
- */
-static void
-common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
-{
- ktime_t now, remaining, iv;
- struct hrtimer *timer = &timr->it.real.timer;
-
- memset(cur_setting, 0, sizeof(struct itimerspec));
-
- iv = timr->it.real.interval;
-
- /* interval timer ? */
- if (iv.tv64)
- cur_setting->it_interval = ktime_to_timespec(iv);
- else if (!hrtimer_active(timer) &&
- (timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
- return;
-
- now = timer->base->get_time();
-
- /*
- * When a requeue is pending or this is a SIGEV_NONE
- * timer move the expiry time forward by intervals, so
- * expiry is > now.
- */
- if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
- (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
- timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
-
- remaining = ktime_sub(hrtimer_get_expires(timer), now);
- /* Return 0 only, when the timer is expired and not pending */
- if (remaining.tv64 <= 0) {
- /*
- * A single shot SIGEV_NONE timer must return 0, when
- * it is expired !
- */
- if ((timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
- cur_setting->it_value.tv_nsec = 1;
- } else
- cur_setting->it_value = ktime_to_timespec(remaining);
-}
-
-/* Get the time remaining on a POSIX.1b interval timer. */
-SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
- struct itimerspec __user *, setting)
-{
- struct itimerspec cur_setting;
- struct k_itimer *timr;
- struct k_clock *kc;
- unsigned long flags;
- int ret = 0;
-
- timr = lock_timer(timer_id, &flags);
- if (!timr)
- return -EINVAL;
-
- kc = clockid_to_kclock(timr->it_clock);
- if (WARN_ON_ONCE(!kc || !kc->timer_get))
- ret = -EINVAL;
- else
- kc->timer_get(timr, &cur_setting);
-
- unlock_timer(timr, flags);
-
- if (!ret && copy_to_user(setting, &cur_setting, sizeof (cur_setting)))
- return -EFAULT;
-
- return ret;
-}
-
-/*
- * Get the number of overruns of a POSIX.1b interval timer. This is to
- * be the overrun of the timer last delivered. At the same time we are
- * accumulating overruns on the next timer. The overrun is frozen when
- * the signal is delivered, either at the notify time (if the info block
- * is not queued) or at the actual delivery time (as we are informed by
- * the call back to do_schedule_next_timer(). So all we need to do is
- * to pick up the frozen overrun.
- */
-SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
-{
- struct k_itimer *timr;
- int overrun;
- unsigned long flags;
-
- timr = lock_timer(timer_id, &flags);
- if (!timr)
- return -EINVAL;
-
- overrun = timr->it_overrun_last;
- unlock_timer(timr, flags);
-
- return overrun;
-}
-
-/* Set a POSIX.1b interval timer. */
-/* timr->it_lock is taken. */
-static int
-common_timer_set(struct k_itimer *timr, int flags,
- struct itimerspec *new_setting, struct itimerspec *old_setting)
-{
- struct hrtimer *timer = &timr->it.real.timer;
- enum hrtimer_mode mode;
-
- if (old_setting)
- common_timer_get(timr, old_setting);
-
- /* disable the timer */
- timr->it.real.interval.tv64 = 0;
- /*
- * careful here. If smp we could be in the "fire" routine which will
- * be spinning as we hold the lock. But this is ONLY an SMP issue.
- */
- if (hrtimer_try_to_cancel(timer) < 0)
- return TIMER_RETRY;
-
- timr->it_requeue_pending = (timr->it_requeue_pending + 2) &
- ~REQUEUE_PENDING;
- timr->it_overrun_last = 0;
-
- /* switch off the timer when it_value is zero */
- if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
- return 0;
-
- mode = flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL;
- hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
- timr->it.real.timer.function = posix_timer_fn;
-
- hrtimer_set_expires(timer, timespec_to_ktime(new_setting->it_value));
-
- /* Convert interval */
- timr->it.real.interval = timespec_to_ktime(new_setting->it_interval);
-
- /* SIGEV_NONE timers are not queued ! See common_timer_get */
- if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
- /* Setup correct expiry time for relative timers */
- if (mode == HRTIMER_MODE_REL) {
- hrtimer_add_expires(timer, timer->base->get_time());
- }
- return 0;
- }
-
- hrtimer_start_expires(timer, mode);
- return 0;
-}
-
-/* Set a POSIX.1b interval timer */
-SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
- const struct itimerspec __user *, new_setting,
- struct itimerspec __user *, old_setting)
-{
- struct k_itimer *timr;
- struct itimerspec new_spec, old_spec;
- int error = 0;
- unsigned long flag;
- struct itimerspec *rtn = old_setting ? &old_spec : NULL;
- struct k_clock *kc;
-
- if (!new_setting)
- return -EINVAL;
-
- if (copy_from_user(&new_spec, new_setting, sizeof (new_spec)))
- return -EFAULT;
-
- if (!timespec_valid(&new_spec.it_interval) ||
- !timespec_valid(&new_spec.it_value))
- return -EINVAL;
-retry:
- timr = lock_timer(timer_id, &flag);
- if (!timr)
- return -EINVAL;
-
- kc = clockid_to_kclock(timr->it_clock);
- if (WARN_ON_ONCE(!kc || !kc->timer_set))
- error = -EINVAL;
- else
- error = kc->timer_set(timr, flags, &new_spec, rtn);
-
- unlock_timer(timr, flag);
- if (error == TIMER_RETRY) {
- rtn = NULL; // We already got the old time...
- goto retry;
- }
-
- if (old_setting && !error &&
- copy_to_user(old_setting, &old_spec, sizeof (old_spec)))
- error = -EFAULT;
-
- return error;
-}
-
-static int common_timer_del(struct k_itimer *timer)
-{
- timer->it.real.interval.tv64 = 0;
-
- if (hrtimer_try_to_cancel(&timer->it.real.timer) < 0)
- return TIMER_RETRY;
- return 0;
-}
-
-static inline int timer_delete_hook(struct k_itimer *timer)
-{
- struct k_clock *kc = clockid_to_kclock(timer->it_clock);
-
- if (WARN_ON_ONCE(!kc || !kc->timer_del))
- return -EINVAL;
- return kc->timer_del(timer);
-}
-
-/* Delete a POSIX.1b interval timer. */
-SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
-{
- struct k_itimer *timer;
- unsigned long flags;
-
-retry_delete:
- timer = lock_timer(timer_id, &flags);
- if (!timer)
- return -EINVAL;
-
- if (timer_delete_hook(timer) == TIMER_RETRY) {
- unlock_timer(timer, flags);
- goto retry_delete;
- }
-
- spin_lock(&current->sighand->siglock);
- list_del(&timer->list);
- spin_unlock(&current->sighand->siglock);
- /*
- * This keeps any tasks waiting on the spin lock from thinking
- * they got something (see the lock code above).
- */
- timer->it_signal = NULL;
-
- unlock_timer(timer, flags);
- release_posix_timer(timer, IT_ID_SET);
- return 0;
-}
-
-/*
- * return timer owned by the process, used by exit_itimers
- */
-static void itimer_delete(struct k_itimer *timer)
-{
- unsigned long flags;
-
-retry_delete:
- spin_lock_irqsave(&timer->it_lock, flags);
-
- if (timer_delete_hook(timer) == TIMER_RETRY) {
- unlock_timer(timer, flags);
- goto retry_delete;
- }
- list_del(&timer->list);
- /*
- * This keeps any tasks waiting on the spin lock from thinking
- * they got something (see the lock code above).
- */
- timer->it_signal = NULL;
-
- unlock_timer(timer, flags);
- release_posix_timer(timer, IT_ID_SET);
-}
-
-/*
- * This is called by do_exit or de_thread, only when there are no more
- * references to the shared signal_struct.
- */
-void exit_itimers(struct signal_struct *sig)
-{
- struct k_itimer *tmr;
-
- while (!list_empty(&sig->posix_timers)) {
- tmr = list_entry(sig->posix_timers.next, struct k_itimer, list);
- itimer_delete(tmr);
- }
-}
-
-SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
- const struct timespec __user *, tp)
-{
- struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec new_tp;
-
- if (!kc || !kc->clock_set)
- return -EINVAL;
-
- if (copy_from_user(&new_tp, tp, sizeof (*tp)))
- return -EFAULT;
-
- return kc->clock_set(which_clock, &new_tp);
-}
-
-SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
- struct timespec __user *,tp)
-{
- struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec kernel_tp;
- int error;
-
- if (!kc)
- return -EINVAL;
-
- error = kc->clock_get(which_clock, &kernel_tp);
-
- if (!error && copy_to_user(tp, &kernel_tp, sizeof (kernel_tp)))
- error = -EFAULT;
-
- return error;
-}
-
-SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
- struct timex __user *, utx)
-{
- struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timex ktx;
- int err;
-
- if (!kc)
- return -EINVAL;
- if (!kc->clock_adj)
- return -EOPNOTSUPP;
-
- if (copy_from_user(&ktx, utx, sizeof(ktx)))
- return -EFAULT;
-
- err = kc->clock_adj(which_clock, &ktx);
-
- if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
- return -EFAULT;
-
- return err;
-}
-
-SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
- struct timespec __user *, tp)
-{
- struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec rtn_tp;
- int error;
-
- if (!kc)
- return -EINVAL;
-
- error = kc->clock_getres(which_clock, &rtn_tp);
-
- if (!error && tp && copy_to_user(tp, &rtn_tp, sizeof (rtn_tp)))
- error = -EFAULT;
-
- return error;
-}
-
-/*
- * nanosleep for monotonic and realtime clocks
- */
-static int common_nsleep(const clockid_t which_clock, int flags,
- struct timespec *tsave, struct timespec __user *rmtp)
-{
- return hrtimer_nanosleep(tsave, rmtp, flags & TIMER_ABSTIME ?
- HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
- which_clock);
-}
-
-SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
- const struct timespec __user *, rqtp,
- struct timespec __user *, rmtp)
-{
- struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec t;
-
- if (!kc)
- return -EINVAL;
- if (!kc->nsleep)
- return -ENANOSLEEP_NOTSUP;
-
- if (copy_from_user(&t, rqtp, sizeof (struct timespec)))
- return -EFAULT;
-
- if (!timespec_valid(&t))
- return -EINVAL;
-
- return kc->nsleep(which_clock, flags, &t, rmtp);
-}
-
-/*
- * This will restart clock_nanosleep. This is required only by
- * compat_clock_nanosleep_restart for now.
- */
-long clock_nanosleep_restart(struct restart_block *restart_block)
-{
- clockid_t which_clock = restart_block->nanosleep.clockid;
- struct k_clock *kc = clockid_to_kclock(which_clock);
-
- if (WARN_ON_ONCE(!kc || !kc->nsleep_restart))
- return -EINVAL;
-
- return kc->nsleep_restart(restart_block);
-}