From e4b765551aa6355eae60b644bed851a9477c4e2b Mon Sep 17 00:00:00 2001 From: Toyo Abe Date: Fri, 29 Sep 2006 02:00:29 -0700 Subject: [PATCH] posix-timers: Fix the flags handling in posix_cpu_nsleep() When a posix_cpu_nsleep() sleep is interrupted by a signal more than twice, it incorrectly reports the sleep time remaining to the user. Because posix_cpu_nsleep() doesn't report back to the user when it's called from restart function due to the wrong flags handling. This patch, which applies after previous one, moves the nanosleep() function from posix_cpu_nsleep() to do_cpu_nanosleep() and cleans up the flags handling appropriately. Signed-off-by: Toyo Abe Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Roland McGrath Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/posix-cpu-timers.c | 84 ++++++++++++++++++++++++++++++++--------------- 1 file changed, 58 insertions(+), 26 deletions(-) (limited to 'kernel') diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 5667fef89dd1..479b16b44f79 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -1393,22 +1393,12 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, } } -int posix_cpu_nsleep(const clockid_t which_clock, int flags, - struct timespec *rqtp, struct timespec __user *rmtp) +static int do_cpu_nanosleep(const clockid_t which_clock, int flags, + struct timespec *rqtp, struct itimerspec *it) { - struct restart_block *restart_block = - ¤t_thread_info()->restart_block; struct k_itimer timer; int error; - /* - * Diagnose required errors first. - */ - if (CPUCLOCK_PERTHREAD(which_clock) && - (CPUCLOCK_PID(which_clock) == 0 || - CPUCLOCK_PID(which_clock) == current->pid)) - return -EINVAL; - /* * Set up a temporary timer and then wait for it to go off. */ @@ -1420,11 +1410,12 @@ int posix_cpu_nsleep(const clockid_t which_clock, int flags, timer.it_process = current; if (!error) { static struct itimerspec zero_it; - struct itimerspec it = { .it_value = *rqtp, - .it_interval = {} }; + + memset(it, 0, sizeof *it); + it->it_value = *rqtp; spin_lock_irq(&timer.it_lock); - error = posix_cpu_timer_set(&timer, flags, &it, NULL); + error = posix_cpu_timer_set(&timer, flags, it, NULL); if (error) { spin_unlock_irq(&timer.it_lock); return error; @@ -1452,33 +1443,56 @@ int posix_cpu_nsleep(const clockid_t which_clock, int flags, * We were interrupted by a signal. */ sample_to_timespec(which_clock, timer.it.cpu.expires, rqtp); - posix_cpu_timer_set(&timer, 0, &zero_it, &it); + posix_cpu_timer_set(&timer, 0, &zero_it, it); spin_unlock_irq(&timer.it_lock); - if ((it.it_value.tv_sec | it.it_value.tv_nsec) == 0) { + if ((it->it_value.tv_sec | it->it_value.tv_nsec) == 0) { /* * It actually did fire already. */ return 0; } + error = -ERESTART_RESTARTBLOCK; + } + + return error; +} + +int posix_cpu_nsleep(const clockid_t which_clock, int flags, + struct timespec *rqtp, struct timespec __user *rmtp) +{ + struct restart_block *restart_block = + ¤t_thread_info()->restart_block; + struct itimerspec it; + int error; + + /* + * Diagnose required errors first. + */ + if (CPUCLOCK_PERTHREAD(which_clock) && + (CPUCLOCK_PID(which_clock) == 0 || + CPUCLOCK_PID(which_clock) == current->pid)) + return -EINVAL; + + error = do_cpu_nanosleep(which_clock, flags, rqtp, &it); + + if (error == -ERESTART_RESTARTBLOCK) { + + if (flags & TIMER_ABSTIME) + return -ERESTARTNOHAND; /* - * Report back to the user the time still remaining. - */ - if (rmtp != NULL && !(flags & TIMER_ABSTIME) && - copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) + * Report back to the user the time still remaining. + */ + if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) return -EFAULT; restart_block->fn = posix_cpu_nsleep_restart; - /* Caller already set restart_block->arg1 */ restart_block->arg0 = which_clock; restart_block->arg1 = (unsigned long) rmtp; restart_block->arg2 = rqtp->tv_sec; restart_block->arg3 = rqtp->tv_nsec; - - error = -ERESTART_RESTARTBLOCK; } - return error; } @@ -1487,13 +1501,31 @@ long posix_cpu_nsleep_restart(struct restart_block *restart_block) clockid_t which_clock = restart_block->arg0; struct timespec __user *rmtp; struct timespec t; + struct itimerspec it; + int error; rmtp = (struct timespec __user *) restart_block->arg1; t.tv_sec = restart_block->arg2; t.tv_nsec = restart_block->arg3; restart_block->fn = do_no_restart_syscall; - return posix_cpu_nsleep(which_clock, TIMER_ABSTIME, &t, rmtp); + error = do_cpu_nanosleep(which_clock, TIMER_ABSTIME, &t, &it); + + if (error == -ERESTART_RESTARTBLOCK) { + /* + * Report back to the user the time still remaining. + */ + if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) + return -EFAULT; + + restart_block->fn = posix_cpu_nsleep_restart; + restart_block->arg0 = which_clock; + restart_block->arg1 = (unsigned long) rmtp; + restart_block->arg2 = t.tv_sec; + restart_block->arg3 = t.tv_nsec; + } + return error; + } -- cgit v1.2.3