Messages in this thread | | | From | Arnd Bergmann <> | Date | Sat, 5 Aug 2017 22:13:50 +0200 | Subject | Re: [PATCH 2/2] io_getevents: Use timespec64 to represent timeouts |
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On Sat, Aug 5, 2017 at 6:12 AM, Deepa Dinamani <deepa.kernel@gmail.com> wrote: > struct timespec is not y2038 safe. Use y2038 safe > struct timespec64 to represent timeouts. > The system call interface itself will be changed as > part of different series. > > Timeouts will not really need more than 32 bits. > But, replacing these with timespec64 helps verification > of a y2038 safe kernel by getting rid of timespec > internally. > > Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> > Cc: linux-aio@kvack.org
Nice cleanup of the compat path!
> static long read_events(struct kioctx *ctx, long min_nr, long nr, > struct io_event __user *event, > - struct timespec __user *timeout) > + ktime_t until) > { > - ktime_t until = KTIME_MAX; > long ret = 0; > > - if (timeout) { > - struct timespec ts; > - > - if (unlikely(copy_from_user(&ts, timeout, sizeof(ts)))) > - return -EFAULT; > - > - until = timespec_to_ktime(ts); > - } > - > /* > * Note that aio_read_events() is being called as the conditional - i.e. > * we're calling it after prepare_to_wait() has set task state to > @@ -1824,6 +1814,25 @@ SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb, > return ret; > } > > +static long do_io_getevents(aio_context_t ctx_id, > + long min_nr, > + long nr, > + struct io_event __user *events, > + struct timespec64 *ts) > +{ > + ktime_t until = ts ? timespec64_to_ktime(*ts) : KTIME_MAX; > + struct kioctx *ioctx = lookup_ioctx(ctx_id); > + long ret = -EINVAL; > + > + if (likely(ioctx)) { > + if (likely(min_nr <= nr && min_nr >= 0)) > + ret = read_events(ioctx, min_nr, nr, events, until); > + percpu_ref_put(&ioctx->users); > + } > + > + return ret; > +}
I guess these two functions are small enough that they could be merged into one, saving a few lines. Then again, fs/aio.c seems to generally use fairly short functions doing not too much at once, so your approach maybe fits better with the style of the subsystem.
Either way,
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Arnd
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