| Message ID | 1412692792-12325-5-git-send-email-cornelia.huck@de.ibm.com |
|---|---|
| State | New |
| Headers | show |
On Tue, Oct 07, 2014 at 04:39:45PM +0200, Cornelia Huck wrote: > From: Rusty Russell <rusty@rustcorp.com.au> > > [Cornelia Huck: we don't need the vq->vring.num -> vq->ring_mask change] > Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> > Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> > --- > drivers/virtio/virtio_ring.c | 195 ++++++++++++++++++++++++++++++------------ > 1 file changed, 138 insertions(+), 57 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index 1cfb5ba..350c39b 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -145,42 +145,54 @@ static inline int vring_add_indirect(struct vring_virtqueue *vq, > i = 0; > for (n = 0; n < out_sgs; n++) { > for (sg = sgs[n]; sg; sg = next(sg, &total_out)) { > - desc[i].flags = VRING_DESC_F_NEXT; > - desc[i].addr = sg_phys(sg); > - desc[i].len = sg->length; > - desc[i].next = i+1; > + desc[i].flags = cpu_to_virtio16(vq->vq.vdev, > + VRING_DESC_F_NEXT); > + desc[i].addr = cpu_to_virtio64(vq->vq.vdev, > + sg_phys(sg)); > + desc[i].len = cpu_to_virtio32(vq->vq.vdev, > + sg->length); > + desc[i].next = cpu_to_virtio16(vq->vq.vdev, > + i+1); > i++; > } > } > for (; n < (out_sgs + in_sgs); n++) { > for (sg = sgs[n]; sg; sg = next(sg, &total_in)) { > - desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE; > - desc[i].addr = sg_phys(sg); > - desc[i].len = sg->length; > - desc[i].next = i+1; > + desc[i].flags = cpu_to_virtio16(vq->vq.vdev, > + VRING_DESC_F_NEXT| > + VRING_DESC_F_WRITE); > + desc[i].addr = cpu_to_virtio64(vq->vq.vdev, > + sg_phys(sg)); > + desc[i].len = cpu_to_virtio32(vq->vq.vdev, > + sg->length); > + desc[i].next = cpu_to_virtio16(vq->vq.vdev, i+1); > i++; > } > } > - BUG_ON(i != total_sg); > > /* Last one doesn't continue. */ > - desc[i-1].flags &= ~VRING_DESC_F_NEXT; > + desc[i-1].flags &= ~cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT); > desc[i-1].next = 0; > > - /* We're about to use a buffer */ > - vq->vq.num_free--; > - > /* Use a single buffer which doesn't continue */ > head = vq->free_head; > - vq->vring.desc[head].flags = VRING_DESC_F_INDIRECT; > - vq->vring.desc[head].addr = virt_to_phys(desc); > + vq->vring.desc[head].flags = > + cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_INDIRECT); > + vq->vring.desc[head].addr = > + cpu_to_virtio64(vq->vq.vdev, virt_to_phys(desc)); > /* kmemleak gives a false positive, as it's hidden by virt_to_phys */ > kmemleak_ignore(desc); > - vq->vring.desc[head].len = i * sizeof(struct vring_desc); > + vq->vring.desc[head].len = > + cpu_to_virtio32(vq->vq.vdev, i * sizeof(struct vring_desc)); > > - /* Update free pointer */ > + BUG_ON(i != total_sg); > + Why move the BUG_ON here? I think I'll move it back ... > + /* Update free pointer (we store this in native endian) */ > vq->free_head = vq->vring.desc[head].next; > > + /* We've just used a buffer */ > + vq->vq.num_free--; > + > return head; > } > > @@ -199,6 +211,7 @@ static inline int virtqueue_add(struct virtqueue *_vq, > struct scatterlist *sg; > unsigned int i, n, avail, uninitialized_var(prev), total_sg; > int head; > + u16 nexti; > > START_USE(vq); > > @@ -253,26 +266,46 @@ static inline int virtqueue_add(struct virtqueue *_vq, > vq->vq.num_free -= total_sg; > > head = i = vq->free_head; > + > for (n = 0; n < out_sgs; n++) { > for (sg = sgs[n]; sg; sg = next(sg, &total_out)) { > - vq->vring.desc[i].flags = VRING_DESC_F_NEXT; > - vq->vring.desc[i].addr = sg_phys(sg); > - vq->vring.desc[i].len = sg->length; > + vq->vring.desc[i].flags = > + cpu_to_virtio16(vq->vq.vdev, > + VRING_DESC_F_NEXT); > + vq->vring.desc[i].addr = > + cpu_to_virtio64(vq->vq.vdev, sg_phys(sg)); > + vq->vring.desc[i].len = > + cpu_to_virtio32(vq->vq.vdev, sg->length); > + > + /* We chained .next in native: fix endian. */ > + nexti = vq->vring.desc[i].next; > + vq->vring.desc[i].next > + = virtio_to_cpu_u16(vq->vq.vdev, nexti); > prev = i; > - i = vq->vring.desc[i].next; > + i = nexti; > } > } > for (; n < (out_sgs + in_sgs); n++) { > for (sg = sgs[n]; sg; sg = next(sg, &total_in)) { > - vq->vring.desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE; > - vq->vring.desc[i].addr = sg_phys(sg); > - vq->vring.desc[i].len = sg->length; > + vq->vring.desc[i].flags = > + cpu_to_virtio16(vq->vq.vdev, > + VRING_DESC_F_NEXT| > + VRING_DESC_F_WRITE); > + vq->vring.desc[i].addr = > + cpu_to_virtio64(vq->vq.vdev, sg_phys(sg)); > + vq->vring.desc[i].len = > + cpu_to_virtio32(vq->vq.vdev, sg->length); > + /* We chained .next in native: fix endian. */ > + nexti = vq->vring.desc[i].next; > + vq->vring.desc[i].next = > + virtio_to_cpu_u16(vq->vq.vdev, nexti); > prev = i; > - i = vq->vring.desc[i].next; > + i = nexti; > } > } > /* Last one doesn't continue. */ > - vq->vring.desc[prev].flags &= ~VRING_DESC_F_NEXT; > + vq->vring.desc[prev].flags &= > + ~cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT); > > /* Update free pointer */ > vq->free_head = i; > @@ -283,15 +316,16 @@ add_head: > > /* Put entry in available array (but don't update avail->idx until they > * do sync). */ > - avail = (vq->vring.avail->idx & (vq->vring.num-1)); > - vq->vring.avail->ring[avail] = head; > + avail = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.avail->idx); > + vq->vring.avail->ring[avail & (vq->vring.num - 1)] = > + cpu_to_virtio16(vq->vq.vdev, head); > > - /* Descriptors and available array need to be set before we expose the > - * new available array entries. */ > + /* Descriptors and available array need to be set > + * before we expose the new available array entries. */ > virtio_wmb(vq->weak_barriers); > - vq->vring.avail->idx++; > - vq->num_added++; > + vq->vring.avail->idx = cpu_to_virtio16(vq->vq.vdev, avail + 1); > > + vq->num_added++; > /* This is very unlikely, but theoretically possible. Kick > * just in case. */ > if (unlikely(vq->num_added == (1 << 16) - 1)) > @@ -408,8 +442,9 @@ bool virtqueue_kick_prepare(struct virtqueue *_vq) > * event. */ > virtio_mb(vq->weak_barriers); > > - old = vq->vring.avail->idx - vq->num_added; > - new = vq->vring.avail->idx; > + new = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.avail->idx); > + > + old = new - vq->num_added; > vq->num_added = 0; > > #ifdef DEBUG > @@ -421,10 +456,17 @@ bool virtqueue_kick_prepare(struct virtqueue *_vq) > #endif > > if (vq->event) { > - needs_kick = vring_need_event(vring_avail_event(&vq->vring), > - new, old); > + u16 avail; > + > + avail = virtio_to_cpu_u16(vq->vq.vdev, > + vring_avail_event(&vq->vring)); > + > + needs_kick = vring_need_event(avail, new, old); > } else { > - needs_kick = !(vq->vring.used->flags & VRING_USED_F_NO_NOTIFY); > + u16 flags; > + > + flags = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.used->flags); > + needs_kick = !(flags & VRING_USED_F_NO_NOTIFY); > } > END_USE(vq); > return needs_kick; > @@ -486,11 +528,20 @@ static void detach_buf(struct vring_virtqueue *vq, unsigned int head) > i = head; > > /* Free the indirect table */ > - if (vq->vring.desc[i].flags & VRING_DESC_F_INDIRECT) > - kfree(phys_to_virt(vq->vring.desc[i].addr)); > + if (vq->vring.desc[i].flags & > + cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_INDIRECT)) { > + kfree(phys_to_virt(virtio_to_cpu_u64(vq->vq.vdev, > + vq->vring.desc[i].addr))); > + } > + > + while (vq->vring.desc[i].flags & > + cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT)) { > + u16 next; > > - while (vq->vring.desc[i].flags & VRING_DESC_F_NEXT) { > - i = vq->vring.desc[i].next; > + /* Convert endian of next back to native. */ > + next = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.desc[i].next); > + vq->vring.desc[i].next = next; > + i = next; > vq->vq.num_free++; > } > > @@ -502,7 +553,8 @@ static void detach_buf(struct vring_virtqueue *vq, unsigned int head) > > static inline bool more_used(const struct vring_virtqueue *vq) > { > - return vq->last_used_idx != vq->vring.used->idx; > + return vq->last_used_idx > + != virtio_to_cpu_u16(vq->vq.vdev, vq->vring.used->idx); > } > > /** > @@ -527,6 +579,8 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) > void *ret; > unsigned int i; > u16 last_used; > + const int no_intr = > + cpu_to_virtio16(vq->vq.vdev, VRING_AVAIL_F_NO_INTERRUPT); > > START_USE(vq); > > @@ -545,8 +599,9 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) > virtio_rmb(vq->weak_barriers); > > last_used = (vq->last_used_idx & (vq->vring.num - 1)); > - i = vq->vring.used->ring[last_used].id; > - *len = vq->vring.used->ring[last_used].len; > + i = virtio_to_cpu_u32(vq->vq.vdev, vq->vring.used->ring[last_used].id); > + *len = virtio_to_cpu_u32(vq->vq.vdev, > + vq->vring.used->ring[last_used].len); > > if (unlikely(i >= vq->vring.num)) { > BAD_RING(vq, "id %u out of range\n", i); > @@ -561,10 +616,11 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) > ret = vq->data[i]; > detach_buf(vq, i); > vq->last_used_idx++; > + > /* If we expect an interrupt for the next entry, tell host > * by writing event index and flush out the write before > * the read in the next get_buf call. */ > - if (!(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) { > + if (!(vq->vring.avail->flags & no_intr)) { > vring_used_event(&vq->vring) = vq->last_used_idx; > virtio_mb(vq->weak_barriers); > } > @@ -591,7 +647,8 @@ void virtqueue_disable_cb(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > - vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; > + vq->vring.avail->flags |= > + cpu_to_virtio16(vq->vq.vdev, VRING_AVAIL_F_NO_INTERRUPT); > } > EXPORT_SYMBOL_GPL(virtqueue_disable_cb); > > @@ -619,8 +676,12 @@ unsigned virtqueue_enable_cb_prepare(struct virtqueue *_vq) > /* Depending on the VIRTIO_RING_F_EVENT_IDX feature, we need to > * either clear the flags bit or point the event index at the next > * entry. Always do both to keep code simple. */ > - vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT; > - vring_used_event(&vq->vring) = last_used_idx = vq->last_used_idx; > + vq->vring.avail->flags &= > + cpu_to_virtio16(vq->vq.vdev, ~VRING_AVAIL_F_NO_INTERRUPT); > + last_used_idx = vq->last_used_idx; > + vring_used_event(&vq->vring) = cpu_to_virtio16(vq->vq.vdev, > + last_used_idx); > + > END_USE(vq); > return last_used_idx; > } > @@ -640,7 +701,9 @@ bool virtqueue_poll(struct virtqueue *_vq, unsigned last_used_idx) > struct vring_virtqueue *vq = to_vvq(_vq); > > virtio_mb(vq->weak_barriers); > - return (u16)last_used_idx != vq->vring.used->idx; > + > + return (u16)last_used_idx != > + virtio_to_cpu_u16(vq->vq.vdev, vq->vring.used->idx); > } > EXPORT_SYMBOL_GPL(virtqueue_poll); > > @@ -678,7 +741,7 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb); > bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > - u16 bufs; > + u16 bufs, used_idx; > > START_USE(vq); > > @@ -687,12 +750,17 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) > /* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to > * either clear the flags bit or point the event index at the next > * entry. Always do both to keep code simple. */ > - vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT; > + vq->vring.avail->flags &= > + cpu_to_virtio16(vq->vq.vdev, ~VRING_AVAIL_F_NO_INTERRUPT); > /* TODO: tune this threshold */ > - bufs = (u16)(vq->vring.avail->idx - vq->last_used_idx) * 3 / 4; > - vring_used_event(&vq->vring) = vq->last_used_idx + bufs; > + bufs = (u16)(virtio_to_cpu_u16(vq->vq.vdev, vq->vring.avail->idx) > + - vq->last_used_idx) * 3 / 4; > + vring_used_event(&vq->vring) = > + cpu_to_virtio16(vq->vq.vdev, vq->last_used_idx + bufs); > virtio_mb(vq->weak_barriers); > - if (unlikely((u16)(vq->vring.used->idx - vq->last_used_idx) > bufs)) { > + used_idx = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.used->idx); > + > + if (unlikely((u16)(used_idx - vq->last_used_idx) > bufs)) { > END_USE(vq); > return false; > } > @@ -719,12 +787,19 @@ void *virtqueue_detach_unused_buf(struct virtqueue *_vq) > START_USE(vq); > > for (i = 0; i < vq->vring.num; i++) { > + u16 avail; > + > if (!vq->data[i]) > continue; > /* detach_buf clears data, so grab it now. */ > buf = vq->data[i]; > detach_buf(vq, i); > - vq->vring.avail->idx--; > + > + /* AKA "vq->vring.avail->idx++" */ > + avail = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.avail->idx); > + vq->vring.avail->idx = cpu_to_virtio16(vq->vq.vdev, > + avail - 1); > + > END_USE(vq); > return buf; > } > @@ -800,12 +875,18 @@ struct virtqueue *vring_new_virtqueue(unsigned int index, > vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); > > /* No callback? Tell other side not to bother us. */ > - if (!callback) > - vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; > + if (!callback) { > + u16 flag; > + > + flag = cpu_to_virtio16(vq->vq.vdev, > + VRING_AVAIL_F_NO_INTERRUPT); > + vq->vring.avail->flags |= flag; > + } > > /* Put everything in free lists. */ > vq->free_head = 0; > for (i = 0; i < num-1; i++) { > + /* This is for our use, so always our endian. */ > vq->vring.desc[i].next = i+1; > vq->data[i] = NULL; > } > -- > 1.7.9.5 > > _______________________________________________ > Virtualization mailing list > Virtualization@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/virtualization
On Wed, 22 Oct 2014 17:02:26 +0300 "Michael S. Tsirkin" <mst@redhat.com> wrote: > On Tue, Oct 07, 2014 at 04:39:45PM +0200, Cornelia Huck wrote: > > From: Rusty Russell <rusty@rustcorp.com.au> > > > > [Cornelia Huck: we don't need the vq->vring.num -> vq->ring_mask change] > > Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> > > Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> > > --- > > drivers/virtio/virtio_ring.c | 195 ++++++++++++++++++++++++++++++------------ > > 1 file changed, 138 insertions(+), 57 deletions(-) > > > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > > index 1cfb5ba..350c39b 100644 > > --- a/drivers/virtio/virtio_ring.c > > +++ b/drivers/virtio/virtio_ring.c > > @@ -145,42 +145,54 @@ static inline int vring_add_indirect(struct vring_virtqueue *vq, > > i = 0; > > for (n = 0; n < out_sgs; n++) { > > for (sg = sgs[n]; sg; sg = next(sg, &total_out)) { > > - desc[i].flags = VRING_DESC_F_NEXT; > > - desc[i].addr = sg_phys(sg); > > - desc[i].len = sg->length; > > - desc[i].next = i+1; > > + desc[i].flags = cpu_to_virtio16(vq->vq.vdev, > > + VRING_DESC_F_NEXT); > > + desc[i].addr = cpu_to_virtio64(vq->vq.vdev, > > + sg_phys(sg)); > > + desc[i].len = cpu_to_virtio32(vq->vq.vdev, > > + sg->length); > > + desc[i].next = cpu_to_virtio16(vq->vq.vdev, > > + i+1); > > i++; > > } > > } > > for (; n < (out_sgs + in_sgs); n++) { > > for (sg = sgs[n]; sg; sg = next(sg, &total_in)) { > > - desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE; > > - desc[i].addr = sg_phys(sg); > > - desc[i].len = sg->length; > > - desc[i].next = i+1; > > + desc[i].flags = cpu_to_virtio16(vq->vq.vdev, > > + VRING_DESC_F_NEXT| > > + VRING_DESC_F_WRITE); > > + desc[i].addr = cpu_to_virtio64(vq->vq.vdev, > > + sg_phys(sg)); > > + desc[i].len = cpu_to_virtio32(vq->vq.vdev, > > + sg->length); > > + desc[i].next = cpu_to_virtio16(vq->vq.vdev, i+1); > > i++; > > } > > } > > - BUG_ON(i != total_sg); > > > > /* Last one doesn't continue. */ > > - desc[i-1].flags &= ~VRING_DESC_F_NEXT; > > + desc[i-1].flags &= ~cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT); > > desc[i-1].next = 0; > > > > - /* We're about to use a buffer */ > > - vq->vq.num_free--; > > - > > /* Use a single buffer which doesn't continue */ > > head = vq->free_head; > > - vq->vring.desc[head].flags = VRING_DESC_F_INDIRECT; > > - vq->vring.desc[head].addr = virt_to_phys(desc); > > + vq->vring.desc[head].flags = > > + cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_INDIRECT); > > + vq->vring.desc[head].addr = > > + cpu_to_virtio64(vq->vq.vdev, virt_to_phys(desc)); > > /* kmemleak gives a false positive, as it's hidden by virt_to_phys */ > > kmemleak_ignore(desc); > > - vq->vring.desc[head].len = i * sizeof(struct vring_desc); > > + vq->vring.desc[head].len = > > + cpu_to_virtio32(vq->vq.vdev, i * sizeof(struct vring_desc)); > > > > - /* Update free pointer */ > > + BUG_ON(i != total_sg); > > + > > Why move the BUG_ON here? > I think I'll move it back ... IIRC this was in the original patch I applied - but you're right, the statement can stay in the old place. > > > + /* Update free pointer (we store this in native endian) */ > > vq->free_head = vq->vring.desc[head].next; > > > > + /* We've just used a buffer */ > > + vq->vq.num_free--; > > + > > return head; > > } > >
On Wed, Oct 22, 2014 at 04:28:34PM +0200, Cornelia Huck wrote: > On Wed, 22 Oct 2014 17:02:26 +0300 > "Michael S. Tsirkin" <mst@redhat.com> wrote: > > > On Tue, Oct 07, 2014 at 04:39:45PM +0200, Cornelia Huck wrote: > > > From: Rusty Russell <rusty@rustcorp.com.au> > > > > > > [Cornelia Huck: we don't need the vq->vring.num -> vq->ring_mask change] > > > Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> > > > Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> > > > --- > > > drivers/virtio/virtio_ring.c | 195 ++++++++++++++++++++++++++++++------------ > > > 1 file changed, 138 insertions(+), 57 deletions(-) > > > > > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > > > index 1cfb5ba..350c39b 100644 > > > --- a/drivers/virtio/virtio_ring.c > > > +++ b/drivers/virtio/virtio_ring.c > > > @@ -145,42 +145,54 @@ static inline int vring_add_indirect(struct vring_virtqueue *vq, > > > i = 0; > > > for (n = 0; n < out_sgs; n++) { > > > for (sg = sgs[n]; sg; sg = next(sg, &total_out)) { > > > - desc[i].flags = VRING_DESC_F_NEXT; > > > - desc[i].addr = sg_phys(sg); > > > - desc[i].len = sg->length; > > > - desc[i].next = i+1; > > > + desc[i].flags = cpu_to_virtio16(vq->vq.vdev, > > > + VRING_DESC_F_NEXT); > > > + desc[i].addr = cpu_to_virtio64(vq->vq.vdev, > > > + sg_phys(sg)); > > > + desc[i].len = cpu_to_virtio32(vq->vq.vdev, > > > + sg->length); > > > + desc[i].next = cpu_to_virtio16(vq->vq.vdev, > > > + i+1); > > > i++; > > > } > > > } > > > for (; n < (out_sgs + in_sgs); n++) { > > > for (sg = sgs[n]; sg; sg = next(sg, &total_in)) { > > > - desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE; > > > - desc[i].addr = sg_phys(sg); > > > - desc[i].len = sg->length; > > > - desc[i].next = i+1; > > > + desc[i].flags = cpu_to_virtio16(vq->vq.vdev, > > > + VRING_DESC_F_NEXT| > > > + VRING_DESC_F_WRITE); > > > + desc[i].addr = cpu_to_virtio64(vq->vq.vdev, > > > + sg_phys(sg)); > > > + desc[i].len = cpu_to_virtio32(vq->vq.vdev, > > > + sg->length); > > > + desc[i].next = cpu_to_virtio16(vq->vq.vdev, i+1); > > > i++; > > > } > > > } > > > - BUG_ON(i != total_sg); > > > > > > /* Last one doesn't continue. */ > > > - desc[i-1].flags &= ~VRING_DESC_F_NEXT; > > > + desc[i-1].flags &= ~cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT); > > > desc[i-1].next = 0; > > > > > > - /* We're about to use a buffer */ > > > - vq->vq.num_free--; > > > - > > > /* Use a single buffer which doesn't continue */ > > > head = vq->free_head; > > > - vq->vring.desc[head].flags = VRING_DESC_F_INDIRECT; > > > - vq->vring.desc[head].addr = virt_to_phys(desc); > > > + vq->vring.desc[head].flags = > > > + cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_INDIRECT); > > > + vq->vring.desc[head].addr = > > > + cpu_to_virtio64(vq->vq.vdev, virt_to_phys(desc)); > > > /* kmemleak gives a false positive, as it's hidden by virt_to_phys */ > > > kmemleak_ignore(desc); > > > - vq->vring.desc[head].len = i * sizeof(struct vring_desc); > > > + vq->vring.desc[head].len = > > > + cpu_to_virtio32(vq->vq.vdev, i * sizeof(struct vring_desc)); > > > > > > - /* Update free pointer */ > > > + BUG_ON(i != total_sg); > > > + > > > > Why move the BUG_ON here? > > I think I'll move it back ... > > IIRC this was in the original patch I applied - but you're right, the > statement can stay in the old place. I think I'll do it more gradually: mechanically add accessors everywhere as a 1st step. Split long lines and other cleanup as a second step. > > > > > + /* Update free pointer (we store this in native endian) */ > > > vq->free_head = vq->vring.desc[head].next; > > > > > > + /* We've just used a buffer */ > > > + vq->vq.num_free--; > > > + > > > return head; > > > } > > >
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 1cfb5ba..350c39b 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -145,42 +145,54 @@ static inline int vring_add_indirect(struct vring_virtqueue *vq, i = 0; for (n = 0; n < out_sgs; n++) { for (sg = sgs[n]; sg; sg = next(sg, &total_out)) { - desc[i].flags = VRING_DESC_F_NEXT; - desc[i].addr = sg_phys(sg); - desc[i].len = sg->length; - desc[i].next = i+1; + desc[i].flags = cpu_to_virtio_u16(vq->vq.vdev, + VRING_DESC_F_NEXT); + desc[i].addr = cpu_to_virtio_u64(vq->vq.vdev, + sg_phys(sg)); + desc[i].len = cpu_to_virtio_u32(vq->vq.vdev, + sg->length); + desc[i].next = cpu_to_virtio_u16(vq->vq.vdev, + i+1); i++; } } for (; n < (out_sgs + in_sgs); n++) { for (sg = sgs[n]; sg; sg = next(sg, &total_in)) { - desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE; - desc[i].addr = sg_phys(sg); - desc[i].len = sg->length; - desc[i].next = i+1; + desc[i].flags = cpu_to_virtio_u16(vq->vq.vdev, + VRING_DESC_F_NEXT| + VRING_DESC_F_WRITE); + desc[i].addr = cpu_to_virtio_u64(vq->vq.vdev, + sg_phys(sg)); + desc[i].len = cpu_to_virtio_u32(vq->vq.vdev, + sg->length); + desc[i].next = cpu_to_virtio_u16(vq->vq.vdev, i+1); i++; } } - BUG_ON(i != total_sg); /* Last one doesn't continue. */ - desc[i-1].flags &= ~VRING_DESC_F_NEXT; + desc[i-1].flags &= ~cpu_to_virtio_u16(vq->vq.vdev, VRING_DESC_F_NEXT); desc[i-1].next = 0; - /* We're about to use a buffer */ - vq->vq.num_free--; - /* Use a single buffer which doesn't continue */ head = vq->free_head; - vq->vring.desc[head].flags = VRING_DESC_F_INDIRECT; - vq->vring.desc[head].addr = virt_to_phys(desc); + vq->vring.desc[head].flags = + cpu_to_virtio_u16(vq->vq.vdev, VRING_DESC_F_INDIRECT); + vq->vring.desc[head].addr = + cpu_to_virtio_u64(vq->vq.vdev, virt_to_phys(desc)); /* kmemleak gives a false positive, as it's hidden by virt_to_phys */ kmemleak_ignore(desc); - vq->vring.desc[head].len = i * sizeof(struct vring_desc); + vq->vring.desc[head].len = + cpu_to_virtio_u32(vq->vq.vdev, i * sizeof(struct vring_desc)); - /* Update free pointer */ + BUG_ON(i != total_sg); + + /* Update free pointer (we store this in native endian) */ vq->free_head = vq->vring.desc[head].next; + /* We've just used a buffer */ + vq->vq.num_free--; + return head; } @@ -199,6 +211,7 @@ static inline int virtqueue_add(struct virtqueue *_vq, struct scatterlist *sg; unsigned int i, n, avail, uninitialized_var(prev), total_sg; int head; + u16 nexti; START_USE(vq); @@ -253,26 +266,46 @@ static inline int virtqueue_add(struct virtqueue *_vq, vq->vq.num_free -= total_sg; head = i = vq->free_head; + for (n = 0; n < out_sgs; n++) { for (sg = sgs[n]; sg; sg = next(sg, &total_out)) { - vq->vring.desc[i].flags = VRING_DESC_F_NEXT; - vq->vring.desc[i].addr = sg_phys(sg); - vq->vring.desc[i].len = sg->length; + vq->vring.desc[i].flags = + cpu_to_virtio_u16(vq->vq.vdev, + VRING_DESC_F_NEXT); + vq->vring.desc[i].addr = + cpu_to_virtio_u64(vq->vq.vdev, sg_phys(sg)); + vq->vring.desc[i].len = + cpu_to_virtio_u32(vq->vq.vdev, sg->length); + + /* We chained .next in native: fix endian. */ + nexti = vq->vring.desc[i].next; + vq->vring.desc[i].next + = virtio_to_cpu_u16(vq->vq.vdev, nexti); prev = i; - i = vq->vring.desc[i].next; + i = nexti; } } for (; n < (out_sgs + in_sgs); n++) { for (sg = sgs[n]; sg; sg = next(sg, &total_in)) { - vq->vring.desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE; - vq->vring.desc[i].addr = sg_phys(sg); - vq->vring.desc[i].len = sg->length; + vq->vring.desc[i].flags = + cpu_to_virtio_u16(vq->vq.vdev, + VRING_DESC_F_NEXT| + VRING_DESC_F_WRITE); + vq->vring.desc[i].addr = + cpu_to_virtio_u64(vq->vq.vdev, sg_phys(sg)); + vq->vring.desc[i].len = + cpu_to_virtio_u32(vq->vq.vdev, sg->length); + /* We chained .next in native: fix endian. */ + nexti = vq->vring.desc[i].next; + vq->vring.desc[i].next = + virtio_to_cpu_u16(vq->vq.vdev, nexti); prev = i; - i = vq->vring.desc[i].next; + i = nexti; } } /* Last one doesn't continue. */ - vq->vring.desc[prev].flags &= ~VRING_DESC_F_NEXT; + vq->vring.desc[prev].flags &= + ~cpu_to_virtio_u16(vq->vq.vdev, VRING_DESC_F_NEXT); /* Update free pointer */ vq->free_head = i; @@ -283,15 +316,16 @@ add_head: /* Put entry in available array (but don't update avail->idx until they * do sync). */ - avail = (vq->vring.avail->idx & (vq->vring.num-1)); - vq->vring.avail->ring[avail] = head; + avail = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.avail->idx); + vq->vring.avail->ring[avail & (vq->vring.num - 1)] = + cpu_to_virtio_u16(vq->vq.vdev, head); - /* Descriptors and available array need to be set before we expose the - * new available array entries. */ + /* Descriptors and available array need to be set + * before we expose the new available array entries. */ virtio_wmb(vq->weak_barriers); - vq->vring.avail->idx++; - vq->num_added++; + vq->vring.avail->idx = cpu_to_virtio_u16(vq->vq.vdev, avail + 1); + vq->num_added++; /* This is very unlikely, but theoretically possible. Kick * just in case. */ if (unlikely(vq->num_added == (1 << 16) - 1)) @@ -408,8 +442,9 @@ bool virtqueue_kick_prepare(struct virtqueue *_vq) * event. */ virtio_mb(vq->weak_barriers); - old = vq->vring.avail->idx - vq->num_added; - new = vq->vring.avail->idx; + new = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.avail->idx); + + old = new - vq->num_added; vq->num_added = 0; #ifdef DEBUG @@ -421,10 +456,17 @@ bool virtqueue_kick_prepare(struct virtqueue *_vq) #endif if (vq->event) { - needs_kick = vring_need_event(vring_avail_event(&vq->vring), - new, old); + u16 avail; + + avail = virtio_to_cpu_u16(vq->vq.vdev, + vring_avail_event(&vq->vring)); + + needs_kick = vring_need_event(avail, new, old); } else { - needs_kick = !(vq->vring.used->flags & VRING_USED_F_NO_NOTIFY); + u16 flags; + + flags = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.used->flags); + needs_kick = !(flags & VRING_USED_F_NO_NOTIFY); } END_USE(vq); return needs_kick; @@ -486,11 +528,20 @@ static void detach_buf(struct vring_virtqueue *vq, unsigned int head) i = head; /* Free the indirect table */ - if (vq->vring.desc[i].flags & VRING_DESC_F_INDIRECT) - kfree(phys_to_virt(vq->vring.desc[i].addr)); + if (vq->vring.desc[i].flags & + cpu_to_virtio_u16(vq->vq.vdev, VRING_DESC_F_INDIRECT)) { + kfree(phys_to_virt(virtio_to_cpu_u64(vq->vq.vdev, + vq->vring.desc[i].addr))); + } + + while (vq->vring.desc[i].flags & + cpu_to_virtio_u16(vq->vq.vdev, VRING_DESC_F_NEXT)) { + u16 next; - while (vq->vring.desc[i].flags & VRING_DESC_F_NEXT) { - i = vq->vring.desc[i].next; + /* Convert endian of next back to native. */ + next = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.desc[i].next); + vq->vring.desc[i].next = next; + i = next; vq->vq.num_free++; } @@ -502,7 +553,8 @@ static void detach_buf(struct vring_virtqueue *vq, unsigned int head) static inline bool more_used(const struct vring_virtqueue *vq) { - return vq->last_used_idx != vq->vring.used->idx; + return vq->last_used_idx + != virtio_to_cpu_u16(vq->vq.vdev, vq->vring.used->idx); } /** @@ -527,6 +579,8 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) void *ret; unsigned int i; u16 last_used; + const int no_intr = + cpu_to_virtio_u16(vq->vq.vdev, VRING_AVAIL_F_NO_INTERRUPT); START_USE(vq); @@ -545,8 +599,9 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) virtio_rmb(vq->weak_barriers); last_used = (vq->last_used_idx & (vq->vring.num - 1)); - i = vq->vring.used->ring[last_used].id; - *len = vq->vring.used->ring[last_used].len; + i = virtio_to_cpu_u32(vq->vq.vdev, vq->vring.used->ring[last_used].id); + *len = virtio_to_cpu_u32(vq->vq.vdev, + vq->vring.used->ring[last_used].len); if (unlikely(i >= vq->vring.num)) { BAD_RING(vq, "id %u out of range\n", i); @@ -561,10 +616,11 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) ret = vq->data[i]; detach_buf(vq, i); vq->last_used_idx++; + /* If we expect an interrupt for the next entry, tell host * by writing event index and flush out the write before * the read in the next get_buf call. */ - if (!(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) { + if (!(vq->vring.avail->flags & no_intr)) { vring_used_event(&vq->vring) = vq->last_used_idx; virtio_mb(vq->weak_barriers); } @@ -591,7 +647,8 @@ void virtqueue_disable_cb(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); - vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; + vq->vring.avail->flags |= + cpu_to_virtio_u16(vq->vq.vdev, VRING_AVAIL_F_NO_INTERRUPT); } EXPORT_SYMBOL_GPL(virtqueue_disable_cb); @@ -619,8 +676,12 @@ unsigned virtqueue_enable_cb_prepare(struct virtqueue *_vq) /* Depending on the VIRTIO_RING_F_EVENT_IDX feature, we need to * either clear the flags bit or point the event index at the next * entry. Always do both to keep code simple. */ - vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT; - vring_used_event(&vq->vring) = last_used_idx = vq->last_used_idx; + vq->vring.avail->flags &= + cpu_to_virtio_u16(vq->vq.vdev, ~VRING_AVAIL_F_NO_INTERRUPT); + last_used_idx = vq->last_used_idx; + vring_used_event(&vq->vring) = cpu_to_virtio_u16(vq->vq.vdev, + last_used_idx); + END_USE(vq); return last_used_idx; } @@ -640,7 +701,9 @@ bool virtqueue_poll(struct virtqueue *_vq, unsigned last_used_idx) struct vring_virtqueue *vq = to_vvq(_vq); virtio_mb(vq->weak_barriers); - return (u16)last_used_idx != vq->vring.used->idx; + + return (u16)last_used_idx != + virtio_to_cpu_u16(vq->vq.vdev, vq->vring.used->idx); } EXPORT_SYMBOL_GPL(virtqueue_poll); @@ -678,7 +741,7 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb); bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); - u16 bufs; + u16 bufs, used_idx; START_USE(vq); @@ -687,12 +750,17 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) /* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to * either clear the flags bit or point the event index at the next * entry. Always do both to keep code simple. */ - vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT; + vq->vring.avail->flags &= + cpu_to_virtio_u16(vq->vq.vdev, ~VRING_AVAIL_F_NO_INTERRUPT); /* TODO: tune this threshold */ - bufs = (u16)(vq->vring.avail->idx - vq->last_used_idx) * 3 / 4; - vring_used_event(&vq->vring) = vq->last_used_idx + bufs; + bufs = (u16)(virtio_to_cpu_u16(vq->vq.vdev, vq->vring.avail->idx) + - vq->last_used_idx) * 3 / 4; + vring_used_event(&vq->vring) = + cpu_to_virtio_u16(vq->vq.vdev, vq->last_used_idx + bufs); virtio_mb(vq->weak_barriers); - if (unlikely((u16)(vq->vring.used->idx - vq->last_used_idx) > bufs)) { + used_idx = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.used->idx); + + if (unlikely((u16)(used_idx - vq->last_used_idx) > bufs)) { END_USE(vq); return false; } @@ -719,12 +787,19 @@ void *virtqueue_detach_unused_buf(struct virtqueue *_vq) START_USE(vq); for (i = 0; i < vq->vring.num; i++) { + u16 avail; + if (!vq->data[i]) continue; /* detach_buf clears data, so grab it now. */ buf = vq->data[i]; detach_buf(vq, i); - vq->vring.avail->idx--; + + /* AKA "vq->vring.avail->idx++" */ + avail = virtio_to_cpu_u16(vq->vq.vdev, vq->vring.avail->idx); + vq->vring.avail->idx = cpu_to_virtio_u16(vq->vq.vdev, + avail - 1); + END_USE(vq); return buf; } @@ -800,12 +875,18 @@ struct virtqueue *vring_new_virtqueue(unsigned int index, vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); /* No callback? Tell other side not to bother us. */ - if (!callback) - vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; + if (!callback) { + u16 flag; + + flag = cpu_to_virtio_u16(vq->vq.vdev, + VRING_AVAIL_F_NO_INTERRUPT); + vq->vring.avail->flags |= flag; + } /* Put everything in free lists. */ vq->free_head = 0; for (i = 0; i < num-1; i++) { + /* This is for our use, so always our endian. */ vq->vring.desc[i].next = i+1; vq->data[i] = NULL; }