On Fri, 2021-03-05 at 13:49 +0800, chensong wrote:
>
> On 2021年03月04日 19:36, Florian Bezdeka via Xenomai wrote:
> > Implementation is heavily inspired by the sem_timedwait syscall,
> > but expecting time64 based timespec / timeout.
> >
> > We need two new syscall handlers:
> > - The native one (COBALT_SYSCALL()) to get 32 bit kernels time64
> > aware. This handler is added for 64 bit kernels as well, but not
> > used. As we don't have separate syscall tables for this both
> > worlds we have to add it.
> >
> > - The compat handler (COBALT_SYSCALL32emu()) for x32 or x86
> > applications running on an x86_64 kernel. Otherwise the redirection
> > to the compat / emulation syscalls is broken.
> >
> > Signed-off-by: Florian Bezdeka <[email protected]>
> > ---
> > include/cobalt/uapi/syscall.h | 1 +
> > kernel/cobalt/posix/sem.c | 12 ++++++++++++
> > kernel/cobalt/posix/sem.h | 4 ++++
> > kernel/cobalt/posix/syscall32.c | 12 ++++++++++++
> > kernel/cobalt/posix/syscall32.h | 4 ++++
> > 5 files changed, 33 insertions(+)
> >
> > diff --git a/include/cobalt/uapi/syscall.h b/include/cobalt/uapi/syscall.h
> > index aa3c308d0..9b005da47 100644
> > --- a/include/cobalt/uapi/syscall.h
> > +++ b/include/cobalt/uapi/syscall.h
> > @@ -122,6 +122,7 @@
> > #define sc_cobalt_sendmmsg 99
> > #define sc_cobalt_clock_adjtime 100
> > #define sc_cobalt_thread_setschedprio 101
> > +#define sc_cobalt_sem_timedwait_time64 102
> >
> > #define __NR_COBALT_SYSCALLS 128 /* Power of 2 */
> >
> > diff --git a/kernel/cobalt/posix/sem.c b/kernel/cobalt/posix/sem.c
> > index a0565e9f8..a2211af36 100644
> > --- a/kernel/cobalt/posix/sem.c
> > +++ b/kernel/cobalt/posix/sem.c
> > @@ -430,6 +430,18 @@ COBALT_SYSCALL(sem_timedwait, primary,
> > return __cobalt_sem_timedwait(u_sem, &ts64);
> > }
> >
> > +COBALT_SYSCALL(sem_timedwait_time64, primary,
> > + (struct cobalt_sem_shadow __user *u_sem,
> > + const struct __kernel_timespec __user *u_ts))
> > +{
> > + struct timespec64 ts64;
> > +
> > + if (get_timespec64(&ts64, u_ts))
>
> get_timespec64 didn't exist until kernel 4.13, shall we take care of this?
> get_timespec64 uses copy_from_user, is there any side effect?
Yes and yes. I already noticed it but did not send out v2 due to some
other this I have to address first. Still trying to find a way that
allows us to prevent duplication all the necessary helpers...
>
> > + return -EFAULT;
> > +
> > + return __cobalt_sem_timedwait(u_sem, &ts64);
> > +}
> > +
> > COBALT_SYSCALL(sem_trywait, primary,
> > (struct cobalt_sem_shadow __user *u_sem))
> > {
> > diff --git a/kernel/cobalt/posix/sem.h b/kernel/cobalt/posix/sem.h
> > index 658e11f7a..8491b69ba 100644
> > --- a/kernel/cobalt/posix/sem.h
> > +++ b/kernel/cobalt/posix/sem.h
> > @@ -66,6 +66,10 @@ __cobalt_sem_open(struct cobalt_sem_shadow __user *usm,
> > int __cobalt_sem_timedwait(struct cobalt_sem_shadow __user *u_sem,
> > const struct timespec64 *ts);
> >
> > +COBALT_SYSCALL_DECL(sem_timedwait_time64,
> > + (struct cobalt_sem_shadow __user *u_sem,
> > + const struct __kernel_timespec __user *u_ts));
> > +
> > int __cobalt_sem_destroy(xnhandle_t handle);
> >
> > void cobalt_nsem_reclaim(struct cobalt_process *process);
> > diff --git a/kernel/cobalt/posix/syscall32.c
> > b/kernel/cobalt/posix/syscall32.c
> > index c2a2423ed..d50532952 100644
> > --- a/kernel/cobalt/posix/syscall32.c
> > +++ b/kernel/cobalt/posix/syscall32.c
> > @@ -136,6 +136,18 @@ COBALT_SYSCALL32emu(sem_timedwait, primary,
> > return __cobalt_sem_timedwait(u_sem, &ts64);
> > }
> >
> > +COBALT_SYSCALL32emu(sem_timedwait_time64, primary,
> > + (struct cobalt_sem_shadow __user *u_sem,
> > + const struct __kernel_timespec __user *u_ts))
> > +{
> > + struct timespec64 ts64;
> > +
> > + if (get_timespec64(&ts64, u_ts))
> > + return -EFAULT;
> > +
> > + return __cobalt_sem_timedwait(u_sem, &ts64);
> > +}
> > +
> > COBALT_SYSCALL32emu(clock_getres, current,
> > (clockid_t clock_id,
> > struct old_timespec32 __user *u_ts))
> > diff --git a/kernel/cobalt/posix/syscall32.h
> > b/kernel/cobalt/posix/syscall32.h
> > index d72fd2022..3612bf751 100644
> > --- a/kernel/cobalt/posix/syscall32.h
> > +++ b/kernel/cobalt/posix/syscall32.h
> > @@ -231,4 +231,8 @@ COBALT_SYSCALL32emu_DECL(sem_timedwait,
> > (struct cobalt_sem_shadow __user *u_sem,
> > const struct old_timespec32 __user *u_ts));
> >
> > +COBALT_SYSCALL32emu_DECL(sem_timedwait_time64,
> > + (struct cobalt_sem_shadow __user * u_sem,
> > + const struct __kernel_timespec __user *u_ts));
> > +
> > #endif /* !_COBALT_POSIX_SYSCALL32_H */
> >
>
>
