| Message ID | e8325bef-7e91-5fd4-fa25-74cfa169ffd2@kernel.dk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fs: RWF_NOWAIT should imply IOCB_NOIO | expand |
On Mon, Aug 10, 2020 at 06:48:19PM -0600, Jens Axboe wrote: > With the change allowing read-ahead for IOCB_NOWAIT, we changed the > RWF_NOWAIT semantics of only doing cached reads. Since we know have > IOCB_NOIO to manage that specific side of it, just make RWF_NOWAIT > imply IOCB_NOIO as well to restore the previous behavior. > > Fixes: 2e85abf053b9 ("mm: allow read-ahead with IOCB_NOWAIT set") > Reported-by: Dave Chinner <david@fromorbit.com> > Signed-off-by: Jens Axboe <axboe@kernel.dk> > > --- > > This was a known change with the buffered async read change, but we > didn't have IOCB_NOIO until late in 5.8. Now that bases are synced, > make the change to make RWF_NOWAIT behave like past kernels. > > diff --git a/include/linux/fs.h b/include/linux/fs.h > index bd7ec3eaeed0..f1cca4bfdd7b 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -3293,7 +3293,7 @@ static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags) > if (flags & RWF_NOWAIT) { > if (!(ki->ki_filp->f_mode & FMODE_NOWAIT)) > return -EOPNOTSUPP; > - kiocb_flags |= IOCB_NOWAIT; > + kiocb_flags |= IOCB_NOWAIT | IOCB_NOIO; > } > if (flags & RWF_HIPRI) > kiocb_flags |= IOCB_HIPRI; Looks good. Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff --git a/include/linux/fs.h b/include/linux/fs.h index bd7ec3eaeed0..f1cca4bfdd7b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3293,7 +3293,7 @@ static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags) if (flags & RWF_NOWAIT) { if (!(ki->ki_filp->f_mode & FMODE_NOWAIT)) return -EOPNOTSUPP; - kiocb_flags |= IOCB_NOWAIT; + kiocb_flags |= IOCB_NOWAIT | IOCB_NOIO; } if (flags & RWF_HIPRI) kiocb_flags |= IOCB_HIPRI;
With the change allowing read-ahead for IOCB_NOWAIT, we changed the RWF_NOWAIT semantics of only doing cached reads. Since we know have IOCB_NOIO to manage that specific side of it, just make RWF_NOWAIT imply IOCB_NOIO as well to restore the previous behavior. Fixes: 2e85abf053b9 ("mm: allow read-ahead with IOCB_NOWAIT set") Reported-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> --- This was a known change with the buffered async read change, but we didn't have IOCB_NOIO until late in 5.8. Now that bases are synced, make the change to make RWF_NOWAIT behave like past kernels.