[PATCH v3 6/7] timerfd: Use get_itimerspec64() and put_itimerspec64()

From: Deepa Dinamani
Date: Sat Jun 24 2017 - 14:51:11 EST


Usage of these apis and their compat versions makes
the syscalls: timerfd_settime and timerfd_gettime and
their compat implementations simpler.

This patch also serves as a preparatory patch for changing
syscalls to use new time_t data types to support the
y2038 effort by isolating the processing of user pointers
through these apis.

Signed-off-by: Deepa Dinamani <deepa.kernel@xxxxxxxxx>
---
fs/timerfd.c | 43 +++++++++++++++++++++----------------------
1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/fs/timerfd.c b/fs/timerfd.c
index c543cdb5f8ed..ece0c02d7e63 100644
--- a/fs/timerfd.c
+++ b/fs/timerfd.c
@@ -169,7 +169,7 @@ static ktime_t timerfd_get_remaining(struct timerfd_ctx *ctx)
}

static int timerfd_setup(struct timerfd_ctx *ctx, int flags,
- const struct itimerspec *ktmr)
+ const struct itimerspec64 *ktmr)
{
enum hrtimer_mode htmode;
ktime_t texp;
@@ -178,10 +178,10 @@ static int timerfd_setup(struct timerfd_ctx *ctx, int flags,
htmode = (flags & TFD_TIMER_ABSTIME) ?
HRTIMER_MODE_ABS: HRTIMER_MODE_REL;

- texp = timespec_to_ktime(ktmr->it_value);
+ texp = timespec64_to_ktime(ktmr->it_value);
ctx->expired = 0;
ctx->ticks = 0;
- ctx->tintv = timespec_to_ktime(ktmr->it_interval);
+ ctx->tintv = timespec64_to_ktime(ktmr->it_interval);

if (isalarm(ctx)) {
alarm_init(&ctx->t.alarm,
@@ -432,16 +432,15 @@ SYSCALL_DEFINE2(timerfd_create, int, clockid, int, flags)
}

static int do_timerfd_settime(int ufd, int flags,
- const struct itimerspec *new,
- struct itimerspec *old)
+ const struct itimerspec64 *new,
+ struct itimerspec64 *old)
{
struct fd f;
struct timerfd_ctx *ctx;
int ret;

if ((flags & ~TFD_SETTIME_FLAGS) ||
- !timespec_valid(&new->it_value) ||
- !timespec_valid(&new->it_interval))
+ !itimerspec64_valid(new))
return -EINVAL;

ret = timerfd_fget(ufd, &f);
@@ -487,8 +486,8 @@ static int do_timerfd_settime(int ufd, int flags,
hrtimer_forward_now(&ctx->t.tmr, ctx->tintv);
}

- old->it_value = ktime_to_timespec(timerfd_get_remaining(ctx));
- old->it_interval = ktime_to_timespec(ctx->tintv);
+ old->it_value = ktime_to_timespec64(timerfd_get_remaining(ctx));
+ old->it_interval = ktime_to_timespec64(ctx->tintv);

/*
* Re-program the timer to the new value ...
@@ -500,7 +499,7 @@ static int do_timerfd_settime(int ufd, int flags,
return ret;
}

-static int do_timerfd_gettime(int ufd, struct itimerspec *t)
+static int do_timerfd_gettime(int ufd, struct itimerspec64 *t)
{
struct fd f;
struct timerfd_ctx *ctx;
@@ -525,8 +524,8 @@ static int do_timerfd_gettime(int ufd, struct itimerspec *t)
hrtimer_restart(&ctx->t.tmr);
}
}
- t->it_value = ktime_to_timespec(timerfd_get_remaining(ctx));
- t->it_interval = ktime_to_timespec(ctx->tintv);
+ t->it_value = ktime_to_timespec64(timerfd_get_remaining(ctx));
+ t->it_interval = ktime_to_timespec64(ctx->tintv);
spin_unlock_irq(&ctx->wqh.lock);
fdput(f);
return 0;
@@ -536,15 +535,15 @@ SYSCALL_DEFINE4(timerfd_settime, int, ufd, int, flags,
const struct itimerspec __user *, utmr,
struct itimerspec __user *, otmr)
{
- struct itimerspec new, old;
+ struct itimerspec64 new, old;
int ret;

- if (copy_from_user(&new, utmr, sizeof(new)))
+ if (get_itimerspec64(&new, utmr))
return -EFAULT;
ret = do_timerfd_settime(ufd, flags, &new, &old);
if (ret)
return ret;
- if (otmr && copy_to_user(otmr, &old, sizeof(old)))
+ if (otmr && put_itimerspec64(&old, otmr))
return -EFAULT;

return ret;
@@ -552,11 +551,11 @@ SYSCALL_DEFINE4(timerfd_settime, int, ufd, int, flags,

SYSCALL_DEFINE2(timerfd_gettime, int, ufd, struct itimerspec __user *, otmr)
{
- struct itimerspec kotmr;
+ struct itimerspec64 kotmr;
int ret = do_timerfd_gettime(ufd, &kotmr);
if (ret)
return ret;
- return copy_to_user(otmr, &kotmr, sizeof(kotmr)) ? -EFAULT: 0;
+ return put_itimerspec64(&kotmr, otmr) ? -EFAULT : 0;
}

#ifdef CONFIG_COMPAT
@@ -564,15 +563,15 @@ COMPAT_SYSCALL_DEFINE4(timerfd_settime, int, ufd, int, flags,
const struct compat_itimerspec __user *, utmr,
struct compat_itimerspec __user *, otmr)
{
- struct itimerspec new, old;
+ struct itimerspec64 new, old;
int ret;

- if (get_compat_itimerspec(&new, utmr))
+ if (get_compat_itimerspec64(&new, utmr))
return -EFAULT;
ret = do_timerfd_settime(ufd, flags, &new, &old);
if (ret)
return ret;
- if (otmr && put_compat_itimerspec(otmr, &old))
+ if (otmr && put_compat_itimerspec64(&old, otmr))
return -EFAULT;
return ret;
}
@@ -580,10 +579,10 @@ COMPAT_SYSCALL_DEFINE4(timerfd_settime, int, ufd, int, flags,
COMPAT_SYSCALL_DEFINE2(timerfd_gettime, int, ufd,
struct compat_itimerspec __user *, otmr)
{
- struct itimerspec kotmr;
+ struct itimerspec64 kotmr;
int ret = do_timerfd_gettime(ufd, &kotmr);
if (ret)
return ret;
- return put_compat_itimerspec(otmr, &kotmr) ? -EFAULT: 0;
+ return put_compat_itimerspec64(&kotmr, otmr) ? -EFAULT : 0;
}
#endif
--
2.11.0