[PATCH v4 09/25] posix-timers:Change the implementation for timer_settime syscall

From: Baolin Wang
Date: Mon Jun 01 2015 - 07:56:48 EST


This patch splits out the guts of the timer_settime syscall and
changes the timer_settime syscall implementation to prepare the
converting to 64bit methods for the timer_settime syscall function
in posix-timers.c file.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
kernel/time/posix-timers.c | 41 ++++++++++++++++++++++++++---------------
1 file changed, 26 insertions(+), 15 deletions(-)

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 2adeb29..99ccb3c 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -920,27 +920,18 @@ common_timer_set(struct k_itimer *timr, int flags,
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)
+static int __timer_settime(timer_t timer_id, int flags, struct itimerspec *new_spec,
+ struct itimerspec *old_spec)
{
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)
+ if (!timespec_valid(&new_spec->it_interval) ||
+ !timespec_valid(&new_spec->it_value))
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)
@@ -950,14 +941,34 @@ retry:
if (WARN_ON_ONCE(!kc || !kc->timer_set))
error = -EINVAL;
else
- error = kc->timer_set(timr, flags, &new_spec, rtn);
+ error = kc->timer_set(timr, flags, new_spec, old_spec);

unlock_timer(timr, flag);
if (error == TIMER_RETRY) {
- rtn = NULL; // We already got the old time...
+ old_spec = NULL; // We already got the old time...
goto retry;
}

+ return error;
+}
+
+/* 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 itimerspec new_spec, old_spec;
+ int error = 0;
+ struct itimerspec *rtn = old_setting ? &old_spec : NULL;
+
+ if (!new_setting)
+ return -EINVAL;
+
+ if (copy_from_user(&new_spec, new_setting, sizeof (new_spec)))
+ return -EFAULT;
+
+ error = __timer_settime(timer_id, flags, &new_spec, rtn);
+
if (old_setting && !error &&
copy_to_user(old_setting, &old_spec, sizeof (old_spec)))
error = -EFAULT;
--
1.7.9.5

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