On Tue, Feb 22, 2022 at 11:49 PM Christoph Hellwig <[email protected]> wrote: > > Using local kmaps slightly reduces the chances to stray writes, and > the bvec interface cleans up the code a little bit. > > Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Jason Wang <[email protected]> > --- > drivers/vhost/vringh.c | 18 ++++++++---------- > 1 file changed, 8 insertions(+), 10 deletions(-) > > diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c > index 14e2043d76852..0f22a83fd09af 100644 > --- a/drivers/vhost/vringh.c > +++ b/drivers/vhost/vringh.c > @@ -1173,7 +1173,7 @@ static inline int getu16_iotlb(const struct vringh *vrh, > u16 *val, const __virtio16 *p) > { > struct bio_vec iov; > - void *kaddr, *from; > + void *kaddr; > int ret; > > /* Atomic read is needed for getu16 */ > @@ -1182,10 +1182,9 @@ static inline int getu16_iotlb(const struct vringh > *vrh, > if (ret < 0) > return ret; > > - kaddr = kmap_atomic(iov.bv_page); > - from = kaddr + iov.bv_offset; > - *val = vringh16_to_cpu(vrh, READ_ONCE(*(__virtio16 *)from)); > - kunmap_atomic(kaddr); > + kaddr = bvec_kmap_local(&iov); > + *val = vringh16_to_cpu(vrh, READ_ONCE(*(__virtio16 *)kaddr)); > + kunmap_local(kaddr); > > return 0; > } > @@ -1194,7 +1193,7 @@ static inline int putu16_iotlb(const struct vringh *vrh, > __virtio16 *p, u16 val) > { > struct bio_vec iov; > - void *kaddr, *to; > + void *kaddr; > int ret; > > /* Atomic write is needed for putu16 */ > @@ -1203,10 +1202,9 @@ static inline int putu16_iotlb(const struct vringh > *vrh, > if (ret < 0) > return ret; > > - kaddr = kmap_atomic(iov.bv_page); > - to = kaddr + iov.bv_offset; > - WRITE_ONCE(*(__virtio16 *)to, cpu_to_vringh16(vrh, val)); > - kunmap_atomic(kaddr); > + kaddr = bvec_kmap_local(&iov); > + WRITE_ONCE(*(__virtio16 *)kaddr, cpu_to_vringh16(vrh, val)); > + kunmap_local(kaddr); > > return 0; > } > -- > 2.30.2 > _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
