The clock_getres() callback in struct k_clock is not year 2038 safe on
32bit systems.
To address this implement a new callback clock_getres64() which uses
struct timespec64 along with a default implementation which is a
wrapper for the existing clock_getres() callback. The default callback
is installed at registration time for all posix clocks which are not
yet converted to clock_getres64() and will be removed once this is
completed.
Use the new callback in __clock_getres().
Signed-off-by: Baolin Wang <baolin.w...@linaro.org>
---
include/linux/posix-timers.h | 1 +
kernel/time/posix-timers.c | 31 ++++++++++++++++++++++++-------
2 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
index be2123d..35786c5 100644
--- a/include/linux/posix-timers.h
+++ b/include/linux/posix-timers.h
@@ -98,6 +98,7 @@ struct k_itimer {
struct k_clock {
int (*clock_getres) (const clockid_t which_clock, struct timespec *tp);
+ int (*clock_getres64) (const clockid_t which_clock, struct timespec64
*tp);
int (*clock_set) (const clockid_t which_clock,
const struct timespec *tp);
int (*clock_set64) (const clockid_t which_clock,
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index a5207f0..0b0663a 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -603,6 +603,20 @@ static int default_clock_get64(const clockid_t which_clock,
return ret;
}
+static int default_clock_getres64(const clockid_t which_clock,
+ struct timespec64 *tp64)
+{
+ struct k_clock *kc = clockid_to_kclock(which_clock);
+ struct timespec tp;
+ int ret;
+
+ ret = kc->clock_getres(which_clock, &tp);
+ if (!ret)
+ *tp64 = timespec_to_timespec64(tp);
+
+ return 0;
+}
+
void posix_timers_register_clock(const clockid_t clock_id,
struct k_clock *new_clock)
{
@@ -617,8 +631,8 @@ void posix_timers_register_clock(const clockid_t clock_id,
clock_id);
return;
}
- if (!new_clock->clock_getres) {
- printk(KERN_WARNING "POSIX clock id %d lacks clock_getres()\n",
+ if (!new_clock->clock_getres && !new_clock->clock_getres64) {
+ printk(KERN_WARNING "POSIX clock id %d lacks clock_getres() and
clock_getres64()\n",
clock_id);
return;
}
@@ -631,6 +645,8 @@ void posix_timers_register_clock(const clockid_t clock_id,
new_clock->clock_set64 = default_clock_set64;
if (new_clock->clock_get && !new_clock->clock_get64)
new_clock->clock_get64 = default_clock_get64;
+ if (new_clock->clock_getres && !new_clock->clock_getres64)
+ new_clock->clock_getres64 = default_clock_getres64;
posix_clocks[clock_id] = *new_clock;
}
@@ -678,7 +694,8 @@ static struct k_clock *clockid_to_kclock(const clockid_t id)
return (id & CLOCKFD_MASK) == CLOCKFD ?
&clock_posix_dynamic : &clock_posix_cpu;
- if (id >= MAX_CLOCKS || !posix_clocks[id].clock_getres)
+ if (id >= MAX_CLOCKS || (!posix_clocks[id].clock_getres
+ && !posix_clocks[id].clock_getres64))
return NULL;
return &posix_clocks[id];
}
@@ -1187,25 +1204,25 @@ SYSCALL_DEFINE2(clock_adjtime, const clockid_t,
which_clock,
return err;
}
-static int __clock_getres(clockid_t which_clock, struct timespec *ts)
+static int __clock_getres(clockid_t which_clock, struct timespec64 *ts)
{
struct k_clock *kc = clockid_to_kclock(which_clock);
if (!kc)
return -EINVAL;
- return kc->clock_getres(which_clock, ts);
+ return kc->clock_getres64(which_clock, ts);
}
SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
struct timespec __user *, tp)
{
- struct timespec rtn_tp;
+ struct timespec64 rtn_tp;
int error;
error = __clock_getres(which_clock, &rtn_tp);
- if (!error && tp && copy_to_user(tp, &rtn_tp, sizeof (rtn_tp)))
+ if (!error && tp && put_timespec(&rtn_tp, tp))
error = -EFAULT;
return error;
--
1.7.9.5
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