| Message ID | 20230321154228.182769-5-sgarzare@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vdpa_sim: add support for user VA | expand |
On Tue, Mar 21, 2023 at 11:43 PM Stefano Garzarella <sgarzare@redhat.com> wrote: > > vDPA supports the possibility to use user VA in the iotlb messages. > So, let's add support for user VA in vringh to use it in the vDPA > simulators. > > Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> > --- > > Notes: > v3: > - refactored avoiding code duplication [Eugenio] > v2: > - replace kmap_atomic() with kmap_local_page() [see previous patch] > - fix cast warnings when build with W=1 C=1 > > include/linux/vringh.h | 5 +- > drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- > drivers/vdpa/vdpa_sim/vdpa_sim.c | 4 +- > drivers/vhost/vringh.c | 153 +++++++++++++++++++++++------- > 4 files changed, 127 insertions(+), 37 deletions(-) > > diff --git a/include/linux/vringh.h b/include/linux/vringh.h > index 1991a02c6431..d39b9f2dcba0 100644 > --- a/include/linux/vringh.h > +++ b/include/linux/vringh.h > @@ -32,6 +32,9 @@ struct vringh { > /* Can we get away with weak barriers? */ > bool weak_barriers; > > + /* Use user's VA */ > + bool use_va; > + > /* Last available index we saw (ie. where we're up to). */ > u16 last_avail_idx; > > @@ -279,7 +282,7 @@ void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb, > spinlock_t *iotlb_lock); > > int vringh_init_iotlb(struct vringh *vrh, u64 features, > - unsigned int num, bool weak_barriers, > + unsigned int num, bool weak_barriers, bool use_va, > struct vring_desc *desc, > struct vring_avail *avail, > struct vring_used *used); > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c > index 520646ae7fa0..dfd0e000217b 100644 > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > @@ -2537,7 +2537,7 @@ static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) > > if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) > err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features, > - MLX5_CVQ_MAX_ENT, false, > + MLX5_CVQ_MAX_ENT, false, false, To avoid those changes, would it be better to introduce vringh_init_iotlb_va() so vringh_init_iotlb() can stick to pa. > (struct vring_desc *)(uintptr_t)cvq->desc_addr, > (struct vring_avail *)(uintptr_t)cvq->driver_addr, > (struct vring_used *)(uintptr_t)cvq->device_addr); > diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c > index eea23c630f7c..47cdf2a1f5b8 100644 > --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c > +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c > @@ -60,7 +60,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) > struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; > uint16_t last_avail_idx = vq->vring.last_avail_idx; > > - vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, > + vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, false, > (struct vring_desc *)(uintptr_t)vq->desc_addr, > (struct vring_avail *) > (uintptr_t)vq->driver_addr, > @@ -92,7 +92,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim, > vq->cb = NULL; > vq->private = NULL; > vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features, > - VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL); > + VDPASIM_QUEUE_MAX, false, false, NULL, NULL, NULL); > > vq->vring.notify = NULL; > } > diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c > index 0ba3ef809e48..72c88519329a 100644 > --- a/drivers/vhost/vringh.c > +++ b/drivers/vhost/vringh.c > @@ -1094,10 +1094,18 @@ EXPORT_SYMBOL(vringh_need_notify_kern); > > #if IS_REACHABLE(CONFIG_VHOST_IOTLB) > > +struct iotlb_vec { > + union { > + struct iovec *iovec; > + struct bio_vec *bvec; > + } iov; > + size_t count; > + bool is_iovec; I wonder if this is needed (if vringh is passed to every iotlb_vec helper). > +}; > + > static int iotlb_translate(const struct vringh *vrh, > u64 addr, u64 len, u64 *translated, > - struct bio_vec iov[], > - int iov_size, u32 perm) > + struct iotlb_vec *ivec, u32 perm) > { > struct vhost_iotlb_map *map; > struct vhost_iotlb *iotlb = vrh->iotlb; > @@ -1107,9 +1115,9 @@ static int iotlb_translate(const struct vringh *vrh, > spin_lock(vrh->iotlb_lock); > > while (len > s) { > - u64 size, pa, pfn; > + u64 size; > > - if (unlikely(ret >= iov_size)) { > + if (unlikely(ret >= ivec->count)) { > ret = -ENOBUFS; > break; > } > @@ -1124,10 +1132,22 @@ static int iotlb_translate(const struct vringh *vrh, > } > > size = map->size - addr + map->start; > - pa = map->addr + addr - map->start; > - pfn = pa >> PAGE_SHIFT; > - bvec_set_page(&iov[ret], pfn_to_page(pfn), min(len - s, size), > - pa & (PAGE_SIZE - 1)); > + if (ivec->is_iovec) { > + struct iovec *iovec = ivec->iov.iovec; > + > + iovec[ret].iov_len = min(len - s, size); > + iovec[ret].iov_base = (void __user *)(unsigned long) > + (map->addr + addr - map->start); map->addr - map->start to avoid overflow? > + } else { > + u64 pa = map->addr + addr - map->start; > + u64 pfn = pa >> PAGE_SHIFT; > + struct bio_vec *bvec = ivec->iov.bvec; > + > + bvec_set_page(&bvec[ret], pfn_to_page(pfn), > + min(len - s, size), > + pa & (PAGE_SIZE - 1)); > + } > + > s += size; > addr += size; > ++ret; > @@ -1141,26 +1161,42 @@ static int iotlb_translate(const struct vringh *vrh, > return ret; > } > > +#define IOTLB_IOV_SIZE 16 > + > static inline int copy_from_iotlb(const struct vringh *vrh, void *dst, > void *src, size_t len) > { > + struct iotlb_vec ivec; > + union { > + struct iovec iovec[IOTLB_IOV_SIZE]; > + struct bio_vec bvec[IOTLB_IOV_SIZE]; > + } iov; > u64 total_translated = 0; > > + ivec.iov.iovec = iov.iovec; ivc.iov = iov ? Others look good. Thanks > + ivec.count = IOTLB_IOV_SIZE; > + ivec.is_iovec = vrh->use_va; > + > while (total_translated < len) { > - struct bio_vec iov[16]; > struct iov_iter iter; > u64 translated; > int ret; > > ret = iotlb_translate(vrh, (u64)(uintptr_t)src, > len - total_translated, &translated, > - iov, ARRAY_SIZE(iov), VHOST_MAP_RO); > + &ivec, VHOST_MAP_RO); > if (ret == -ENOBUFS) > - ret = ARRAY_SIZE(iov); > + ret = IOTLB_IOV_SIZE; > else if (ret < 0) > return ret; > > - iov_iter_bvec(&iter, ITER_SOURCE, iov, ret, translated); > + if (ivec.is_iovec) { > + iov_iter_init(&iter, ITER_SOURCE, ivec.iov.iovec, ret, > + translated); > + } else { > + iov_iter_bvec(&iter, ITER_SOURCE, ivec.iov.bvec, ret, > + translated); > + } > > ret = copy_from_iter(dst, translated, &iter); > if (ret < 0) > @@ -1177,23 +1213,37 @@ static inline int copy_from_iotlb(const struct vringh *vrh, void *dst, > static inline int copy_to_iotlb(const struct vringh *vrh, void *dst, > void *src, size_t len) > { > + struct iotlb_vec ivec; > + union { > + struct iovec iovec[IOTLB_IOV_SIZE]; > + struct bio_vec bvec[IOTLB_IOV_SIZE]; > + } iov; > u64 total_translated = 0; > > + ivec.iov.iovec = iov.iovec; > + ivec.count = IOTLB_IOV_SIZE; > + ivec.is_iovec = vrh->use_va; > + > while (total_translated < len) { > - struct bio_vec iov[16]; > struct iov_iter iter; > u64 translated; > int ret; > > ret = iotlb_translate(vrh, (u64)(uintptr_t)dst, > len - total_translated, &translated, > - iov, ARRAY_SIZE(iov), VHOST_MAP_WO); > + &ivec, VHOST_MAP_WO); > if (ret == -ENOBUFS) > - ret = ARRAY_SIZE(iov); > + ret = IOTLB_IOV_SIZE; > else if (ret < 0) > return ret; > > - iov_iter_bvec(&iter, ITER_DEST, iov, ret, translated); > + if (ivec.is_iovec) { > + iov_iter_init(&iter, ITER_DEST, ivec.iov.iovec, ret, > + translated); > + } else { > + iov_iter_bvec(&iter, ITER_DEST, ivec.iov.bvec, ret, > + translated); > + } > > ret = copy_to_iter(src, translated, &iter); > if (ret < 0) > @@ -1210,20 +1260,37 @@ static inline int copy_to_iotlb(const struct vringh *vrh, void *dst, > static inline int getu16_iotlb(const struct vringh *vrh, > u16 *val, const __virtio16 *p) > { > - struct bio_vec iov; > - void *kaddr, *from; > + struct iotlb_vec ivec; > + union { > + struct iovec iovec[1]; > + struct bio_vec bvec[1]; > + } iov; > + __virtio16 tmp; > int ret; > > + ivec.iov.iovec = iov.iovec; > + ivec.count = 1; > + ivec.is_iovec = vrh->use_va; > + > /* Atomic read is needed for getu16 */ > - ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL, > - &iov, 1, VHOST_MAP_RO); > + ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), > + NULL, &ivec, VHOST_MAP_RO); > if (ret < 0) > return ret; > > - kaddr = kmap_local_page(iov.bv_page); > - from = kaddr + iov.bv_offset; > - *val = vringh16_to_cpu(vrh, READ_ONCE(*(__virtio16 *)from)); > - kunmap_local(kaddr); > + if (ivec.is_iovec) { > + ret = __get_user(tmp, (__virtio16 __user *)ivec.iov.iovec[0].iov_base); > + if (ret) > + return ret; > + } else { > + void *kaddr = kmap_local_page(ivec.iov.bvec[0].bv_page); > + void *from = kaddr + ivec.iov.bvec[0].bv_offset; > + > + tmp = READ_ONCE(*(__virtio16 *)from); > + kunmap_local(kaddr); > + } > + > + *val = vringh16_to_cpu(vrh, tmp); > > return 0; > } > @@ -1231,20 +1298,37 @@ static inline int getu16_iotlb(const struct vringh *vrh, > static inline int putu16_iotlb(const struct vringh *vrh, > __virtio16 *p, u16 val) > { > - struct bio_vec iov; > - void *kaddr, *to; > + struct iotlb_vec ivec; > + union { > + struct iovec iovec; > + struct bio_vec bvec; > + } iov; > + __virtio16 tmp; > int ret; > > + ivec.iov.iovec = &iov.iovec; > + ivec.count = 1; > + ivec.is_iovec = vrh->use_va; > + > /* Atomic write is needed for putu16 */ > - ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL, > - &iov, 1, VHOST_MAP_WO); > + ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), > + NULL, &ivec, VHOST_MAP_RO); > if (ret < 0) > return ret; > > - kaddr = kmap_local_page(iov.bv_page); > - to = kaddr + iov.bv_offset; > - WRITE_ONCE(*(__virtio16 *)to, cpu_to_vringh16(vrh, val)); > - kunmap_local(kaddr); > + tmp = cpu_to_vringh16(vrh, val); > + > + if (ivec.is_iovec) { > + ret = __put_user(tmp, (__virtio16 __user *)ivec.iov.iovec[0].iov_base); > + if (ret) > + return ret; > + } else { > + void *kaddr = kmap_local_page(ivec.iov.bvec[0].bv_page); > + void *to = kaddr + ivec.iov.bvec[0].bv_offset; > + > + WRITE_ONCE(*(__virtio16 *)to, tmp); > + kunmap_local(kaddr); > + } > > return 0; > } > @@ -1306,6 +1390,7 @@ static inline int putused_iotlb(const struct vringh *vrh, > * @features: the feature bits for this ring. > * @num: the number of elements. > * @weak_barriers: true if we only need memory barriers, not I/O. > + * @use_va: true if IOTLB contains user VA > * @desc: the userpace descriptor pointer. > * @avail: the userpace avail pointer. > * @used: the userpace used pointer. > @@ -1313,11 +1398,13 @@ static inline int putused_iotlb(const struct vringh *vrh, > * Returns an error if num is invalid. > */ > int vringh_init_iotlb(struct vringh *vrh, u64 features, > - unsigned int num, bool weak_barriers, > + unsigned int num, bool weak_barriers, bool use_va, > struct vring_desc *desc, > struct vring_avail *avail, > struct vring_used *used) > { > + vrh->use_va = use_va; > + > return vringh_init_kern(vrh, features, num, weak_barriers, > desc, avail, used); > } > -- > 2.39.2 >
On Tue, Mar 21, 2023 at 4:43 PM Stefano Garzarella <sgarzare@redhat.com> wrote: > > vDPA supports the possibility to use user VA in the iotlb messages. > So, let's add support for user VA in vringh to use it in the vDPA > simulators. > > Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> > --- > > Notes: > v3: > - refactored avoiding code duplication [Eugenio] > v2: > - replace kmap_atomic() with kmap_local_page() [see previous patch] > - fix cast warnings when build with W=1 C=1 > > include/linux/vringh.h | 5 +- > drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- > drivers/vdpa/vdpa_sim/vdpa_sim.c | 4 +- > drivers/vhost/vringh.c | 153 +++++++++++++++++++++++------- > 4 files changed, 127 insertions(+), 37 deletions(-) > > diff --git a/include/linux/vringh.h b/include/linux/vringh.h > index 1991a02c6431..d39b9f2dcba0 100644 > --- a/include/linux/vringh.h > +++ b/include/linux/vringh.h > @@ -32,6 +32,9 @@ struct vringh { > /* Can we get away with weak barriers? */ > bool weak_barriers; > > + /* Use user's VA */ > + bool use_va; > + > /* Last available index we saw (ie. where we're up to). */ > u16 last_avail_idx; > > @@ -279,7 +282,7 @@ void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb, > spinlock_t *iotlb_lock); > > int vringh_init_iotlb(struct vringh *vrh, u64 features, > - unsigned int num, bool weak_barriers, > + unsigned int num, bool weak_barriers, bool use_va, > struct vring_desc *desc, > struct vring_avail *avail, > struct vring_used *used); > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c > index 520646ae7fa0..dfd0e000217b 100644 > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > @@ -2537,7 +2537,7 @@ static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) > > if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) > err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features, > - MLX5_CVQ_MAX_ENT, false, > + MLX5_CVQ_MAX_ENT, false, false, > (struct vring_desc *)(uintptr_t)cvq->desc_addr, > (struct vring_avail *)(uintptr_t)cvq->driver_addr, > (struct vring_used *)(uintptr_t)cvq->device_addr); > diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c > index eea23c630f7c..47cdf2a1f5b8 100644 > --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c > +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c > @@ -60,7 +60,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) > struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; > uint16_t last_avail_idx = vq->vring.last_avail_idx; > > - vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, > + vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, false, > (struct vring_desc *)(uintptr_t)vq->desc_addr, > (struct vring_avail *) > (uintptr_t)vq->driver_addr, > @@ -92,7 +92,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim, > vq->cb = NULL; > vq->private = NULL; > vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features, > - VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL); > + VDPASIM_QUEUE_MAX, false, false, NULL, NULL, NULL); > > vq->vring.notify = NULL; > } > diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c > index 0ba3ef809e48..72c88519329a 100644 > --- a/drivers/vhost/vringh.c > +++ b/drivers/vhost/vringh.c > @@ -1094,10 +1094,18 @@ EXPORT_SYMBOL(vringh_need_notify_kern); > > #if IS_REACHABLE(CONFIG_VHOST_IOTLB) > > +struct iotlb_vec { > + union { > + struct iovec *iovec; > + struct bio_vec *bvec; > + } iov; > + size_t count; > + bool is_iovec; > +}; > + > static int iotlb_translate(const struct vringh *vrh, > u64 addr, u64 len, u64 *translated, > - struct bio_vec iov[], > - int iov_size, u32 perm) > + struct iotlb_vec *ivec, u32 perm) > { > struct vhost_iotlb_map *map; > struct vhost_iotlb *iotlb = vrh->iotlb; > @@ -1107,9 +1115,9 @@ static int iotlb_translate(const struct vringh *vrh, > spin_lock(vrh->iotlb_lock); > > while (len > s) { > - u64 size, pa, pfn; > + u64 size; > > - if (unlikely(ret >= iov_size)) { > + if (unlikely(ret >= ivec->count)) { > ret = -ENOBUFS; > break; > } > @@ -1124,10 +1132,22 @@ static int iotlb_translate(const struct vringh *vrh, > } > > size = map->size - addr + map->start; > - pa = map->addr + addr - map->start; > - pfn = pa >> PAGE_SHIFT; > - bvec_set_page(&iov[ret], pfn_to_page(pfn), min(len - s, size), > - pa & (PAGE_SIZE - 1)); > + if (ivec->is_iovec) { > + struct iovec *iovec = ivec->iov.iovec; > + > + iovec[ret].iov_len = min(len - s, size); > + iovec[ret].iov_base = (void __user *)(unsigned long) s/unsigned long/uintptr_t ? > + (map->addr + addr - map->start); > + } else { > + u64 pa = map->addr + addr - map->start; > + u64 pfn = pa >> PAGE_SHIFT; > + struct bio_vec *bvec = ivec->iov.bvec; > + > + bvec_set_page(&bvec[ret], pfn_to_page(pfn), > + min(len - s, size), > + pa & (PAGE_SIZE - 1)); > + } > + > s += size; > addr += size; > ++ret; > @@ -1141,26 +1161,42 @@ static int iotlb_translate(const struct vringh *vrh, > return ret; > } > > +#define IOTLB_IOV_SIZE 16 I'm fine with defining here, but maybe it is better to isolate the change in a previous patch or reuse another well known macro? Other looks good, and I agree with Jason's comments so even if the macro declaration is not moved: Acked-by: Eugenio Pérez <eperezma@redhat.com> > + > static inline int copy_from_iotlb(const struct vringh *vrh, void *dst, > void *src, size_t len) > { > + struct iotlb_vec ivec; > + union { > + struct iovec iovec[IOTLB_IOV_SIZE]; > + struct bio_vec bvec[IOTLB_IOV_SIZE]; > + } iov; > u64 total_translated = 0; > > + ivec.iov.iovec = iov.iovec; > + ivec.count = IOTLB_IOV_SIZE; > + ivec.is_iovec = vrh->use_va; > + > while (total_translated < len) { > - struct bio_vec iov[16]; > struct iov_iter iter; > u64 translated; > int ret; > > ret = iotlb_translate(vrh, (u64)(uintptr_t)src, > len - total_translated, &translated, > - iov, ARRAY_SIZE(iov), VHOST_MAP_RO); > + &ivec, VHOST_MAP_RO); > if (ret == -ENOBUFS) > - ret = ARRAY_SIZE(iov); > + ret = IOTLB_IOV_SIZE; > else if (ret < 0) > return ret; > > - iov_iter_bvec(&iter, ITER_SOURCE, iov, ret, translated); > + if (ivec.is_iovec) { > + iov_iter_init(&iter, ITER_SOURCE, ivec.iov.iovec, ret, > + translated); > + } else { > + iov_iter_bvec(&iter, ITER_SOURCE, ivec.iov.bvec, ret, > + translated); > + } > > ret = copy_from_iter(dst, translated, &iter); > if (ret < 0) > @@ -1177,23 +1213,37 @@ static inline int copy_from_iotlb(const struct vringh *vrh, void *dst, > static inline int copy_to_iotlb(const struct vringh *vrh, void *dst, > void *src, size_t len) > { > + struct iotlb_vec ivec; > + union { > + struct iovec iovec[IOTLB_IOV_SIZE]; > + struct bio_vec bvec[IOTLB_IOV_SIZE]; > + } iov; > u64 total_translated = 0; > > + ivec.iov.iovec = iov.iovec; > + ivec.count = IOTLB_IOV_SIZE; > + ivec.is_iovec = vrh->use_va; > + > while (total_translated < len) { > - struct bio_vec iov[16]; > struct iov_iter iter; > u64 translated; > int ret; > > ret = iotlb_translate(vrh, (u64)(uintptr_t)dst, > len - total_translated, &translated, > - iov, ARRAY_SIZE(iov), VHOST_MAP_WO); > + &ivec, VHOST_MAP_WO); > if (ret == -ENOBUFS) > - ret = ARRAY_SIZE(iov); > + ret = IOTLB_IOV_SIZE; > else if (ret < 0) > return ret; > > - iov_iter_bvec(&iter, ITER_DEST, iov, ret, translated); > + if (ivec.is_iovec) { > + iov_iter_init(&iter, ITER_DEST, ivec.iov.iovec, ret, > + translated); > + } else { > + iov_iter_bvec(&iter, ITER_DEST, ivec.iov.bvec, ret, > + translated); > + } > > ret = copy_to_iter(src, translated, &iter); > if (ret < 0) > @@ -1210,20 +1260,37 @@ static inline int copy_to_iotlb(const struct vringh *vrh, void *dst, > static inline int getu16_iotlb(const struct vringh *vrh, > u16 *val, const __virtio16 *p) > { > - struct bio_vec iov; > - void *kaddr, *from; > + struct iotlb_vec ivec; > + union { > + struct iovec iovec[1]; > + struct bio_vec bvec[1]; > + } iov; > + __virtio16 tmp; > int ret; > > + ivec.iov.iovec = iov.iovec; > + ivec.count = 1; > + ivec.is_iovec = vrh->use_va; > + > /* Atomic read is needed for getu16 */ > - ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL, > - &iov, 1, VHOST_MAP_RO); > + ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), > + NULL, &ivec, VHOST_MAP_RO); > if (ret < 0) > return ret; > > - kaddr = kmap_local_page(iov.bv_page); > - from = kaddr + iov.bv_offset; > - *val = vringh16_to_cpu(vrh, READ_ONCE(*(__virtio16 *)from)); > - kunmap_local(kaddr); > + if (ivec.is_iovec) { > + ret = __get_user(tmp, (__virtio16 __user *)ivec.iov.iovec[0].iov_base); > + if (ret) > + return ret; > + } else { > + void *kaddr = kmap_local_page(ivec.iov.bvec[0].bv_page); > + void *from = kaddr + ivec.iov.bvec[0].bv_offset; > + > + tmp = READ_ONCE(*(__virtio16 *)from); > + kunmap_local(kaddr); > + } > + > + *val = vringh16_to_cpu(vrh, tmp); > > return 0; > } > @@ -1231,20 +1298,37 @@ static inline int getu16_iotlb(const struct vringh *vrh, > static inline int putu16_iotlb(const struct vringh *vrh, > __virtio16 *p, u16 val) > { > - struct bio_vec iov; > - void *kaddr, *to; > + struct iotlb_vec ivec; > + union { > + struct iovec iovec; > + struct bio_vec bvec; > + } iov; > + __virtio16 tmp; > int ret; > > + ivec.iov.iovec = &iov.iovec; > + ivec.count = 1; > + ivec.is_iovec = vrh->use_va; > + > /* Atomic write is needed for putu16 */ > - ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL, > - &iov, 1, VHOST_MAP_WO); > + ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), > + NULL, &ivec, VHOST_MAP_RO); > if (ret < 0) > return ret; > > - kaddr = kmap_local_page(iov.bv_page); > - to = kaddr + iov.bv_offset; > - WRITE_ONCE(*(__virtio16 *)to, cpu_to_vringh16(vrh, val)); > - kunmap_local(kaddr); > + tmp = cpu_to_vringh16(vrh, val); > + > + if (ivec.is_iovec) { > + ret = __put_user(tmp, (__virtio16 __user *)ivec.iov.iovec[0].iov_base); > + if (ret) > + return ret; > + } else { > + void *kaddr = kmap_local_page(ivec.iov.bvec[0].bv_page); > + void *to = kaddr + ivec.iov.bvec[0].bv_offset; > + > + WRITE_ONCE(*(__virtio16 *)to, tmp); > + kunmap_local(kaddr); > + } > > return 0; > } > @@ -1306,6 +1390,7 @@ static inline int putused_iotlb(const struct vringh *vrh, > * @features: the feature bits for this ring. > * @num: the number of elements. > * @weak_barriers: true if we only need memory barriers, not I/O. > + * @use_va: true if IOTLB contains user VA > * @desc: the userpace descriptor pointer. > * @avail: the userpace avail pointer. > * @used: the userpace used pointer. > @@ -1313,11 +1398,13 @@ static inline int putused_iotlb(const struct vringh *vrh, > * Returns an error if num is invalid. > */ > int vringh_init_iotlb(struct vringh *vrh, u64 features, > - unsigned int num, bool weak_barriers, > + unsigned int num, bool weak_barriers, bool use_va, > struct vring_desc *desc, > struct vring_avail *avail, > struct vring_used *used) > { > + vrh->use_va = use_va; > + > return vringh_init_kern(vrh, features, num, weak_barriers, > desc, avail, used); > } > -- > 2.39.2 >
On Thu, Mar 23, 2023 at 11:36:28AM +0800, Jason Wang wrote: >On Tue, Mar 21, 2023 at 11:43 PM Stefano Garzarella <sgarzare@redhat.com> wrote: >> >> vDPA supports the possibility to use user VA in the iotlb messages. >> So, let's add support for user VA in vringh to use it in the vDPA >> simulators. >> >> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> >> --- >> >> Notes: >> v3: >> - refactored avoiding code duplication [Eugenio] >> v2: >> - replace kmap_atomic() with kmap_local_page() [see previous patch] >> - fix cast warnings when build with W=1 C=1 >> >> include/linux/vringh.h | 5 +- >> drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- >> drivers/vdpa/vdpa_sim/vdpa_sim.c | 4 +- >> drivers/vhost/vringh.c | 153 +++++++++++++++++++++++------- >> 4 files changed, 127 insertions(+), 37 deletions(-) >> >> diff --git a/include/linux/vringh.h b/include/linux/vringh.h >> index 1991a02c6431..d39b9f2dcba0 100644 >> --- a/include/linux/vringh.h >> +++ b/include/linux/vringh.h >> @@ -32,6 +32,9 @@ struct vringh { >> /* Can we get away with weak barriers? */ >> bool weak_barriers; >> >> + /* Use user's VA */ >> + bool use_va; >> + >> /* Last available index we saw (ie. where we're up to). */ >> u16 last_avail_idx; >> >> @@ -279,7 +282,7 @@ void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb, >> spinlock_t *iotlb_lock); >> >> int vringh_init_iotlb(struct vringh *vrh, u64 features, >> - unsigned int num, bool weak_barriers, >> + unsigned int num, bool weak_barriers, bool use_va, >> struct vring_desc *desc, >> struct vring_avail *avail, >> struct vring_used *used); >> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> index 520646ae7fa0..dfd0e000217b 100644 >> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c >> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> @@ -2537,7 +2537,7 @@ static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) >> >> if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) >> err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features, >> - MLX5_CVQ_MAX_ENT, false, >> + MLX5_CVQ_MAX_ENT, false, false, > >To avoid those changes, would it be better to introduce >vringh_init_iotlb_va() so vringh_init_iotlb() can stick to pa. Okay, I don't have a strong opinion, I'll add vringh_init_iotlb_va(). > >> (struct vring_desc *)(uintptr_t)cvq->desc_addr, >> (struct vring_avail *)(uintptr_t)cvq->driver_addr, >> (struct vring_used *)(uintptr_t)cvq->device_addr); >> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c >> index eea23c630f7c..47cdf2a1f5b8 100644 >> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c >> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c >> @@ -60,7 +60,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) >> struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; >> uint16_t last_avail_idx = vq->vring.last_avail_idx; >> >> - vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, >> + vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, false, >> (struct vring_desc *)(uintptr_t)vq->desc_addr, >> (struct vring_avail *) >> (uintptr_t)vq->driver_addr, >> @@ -92,7 +92,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim, >> vq->cb = NULL; >> vq->private = NULL; >> vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features, >> - VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL); >> + VDPASIM_QUEUE_MAX, false, false, NULL, NULL, NULL); >> >> vq->vring.notify = NULL; >> } >> diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c >> index 0ba3ef809e48..72c88519329a 100644 >> --- a/drivers/vhost/vringh.c >> +++ b/drivers/vhost/vringh.c >> @@ -1094,10 +1094,18 @@ EXPORT_SYMBOL(vringh_need_notify_kern); >> >> #if IS_REACHABLE(CONFIG_VHOST_IOTLB) >> >> +struct iotlb_vec { >> + union { >> + struct iovec *iovec; >> + struct bio_vec *bvec; >> + } iov; >> + size_t count; >> + bool is_iovec; > >I wonder if this is needed (if vringh is passed to every iotlb_vec helper). Yep, I can use vringh->use_va. > >> +}; >> + >> static int iotlb_translate(const struct vringh *vrh, >> u64 addr, u64 len, u64 *translated, >> - struct bio_vec iov[], >> - int iov_size, u32 perm) >> + struct iotlb_vec *ivec, u32 perm) >> { >> struct vhost_iotlb_map *map; >> struct vhost_iotlb *iotlb = vrh->iotlb; >> @@ -1107,9 +1115,9 @@ static int iotlb_translate(const struct vringh *vrh, >> spin_lock(vrh->iotlb_lock); >> >> while (len > s) { >> - u64 size, pa, pfn; >> + u64 size; >> >> - if (unlikely(ret >= iov_size)) { >> + if (unlikely(ret >= ivec->count)) { >> ret = -ENOBUFS; >> break; >> } >> @@ -1124,10 +1132,22 @@ static int iotlb_translate(const struct vringh *vrh, >> } >> >> size = map->size - addr + map->start; >> - pa = map->addr + addr - map->start; >> - pfn = pa >> PAGE_SHIFT; >> - bvec_set_page(&iov[ret], pfn_to_page(pfn), min(len - s, size), >> - pa & (PAGE_SIZE - 1)); >> + if (ivec->is_iovec) { >> + struct iovec *iovec = ivec->iov.iovec; >> + >> + iovec[ret].iov_len = min(len - s, size); >> + iovec[ret].iov_base = (void __user *)(unsigned long) >> + (map->addr + addr - map->start); > >map->addr - map->start to avoid overflow? Right, it was pre-existing, but I'll fix since I'm here (also in the else branch). And since it's duplicate code, I'll declare it outside! > >> + } else { >> + u64 pa = map->addr + addr - map->start; >> + u64 pfn = pa >> PAGE_SHIFT; >> + struct bio_vec *bvec = ivec->iov.bvec; >> + >> + bvec_set_page(&bvec[ret], pfn_to_page(pfn), >> + min(len - s, size), >> + pa & (PAGE_SIZE - 1)); >> + } >> + >> s += size; >> addr += size; >> ++ret; >> @@ -1141,26 +1161,42 @@ static int iotlb_translate(const struct vringh *vrh, >> return ret; >> } >> >> +#define IOTLB_IOV_SIZE 16 >> + >> static inline int copy_from_iotlb(const struct vringh *vrh, void *dst, >> void *src, size_t len) >> { >> + struct iotlb_vec ivec; >> + union { >> + struct iovec iovec[IOTLB_IOV_SIZE]; >> + struct bio_vec bvec[IOTLB_IOV_SIZE]; >> + } iov; >> u64 total_translated = 0; >> >> + ivec.iov.iovec = iov.iovec; > >ivc.iov = iov ? I tried, but they are both anonymous unions, so I cannot assign them. Also, this inner union I need to allocate space in the stack to hold both arrays, while the union in iotlb_vec to carry both pointers. I don't know whether to add a third field (e.g. `void *raw`) to both and assign it. > >Others look good. Thanks, Stefano
On Thu, Mar 23, 2023 at 09:09:14AM +0100, Eugenio Perez Martin wrote: >On Tue, Mar 21, 2023 at 4:43 PM Stefano Garzarella <sgarzare@redhat.com> wrote: >> >> vDPA supports the possibility to use user VA in the iotlb messages. >> So, let's add support for user VA in vringh to use it in the vDPA >> simulators. >> >> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> >> --- >> >> Notes: >> v3: >> - refactored avoiding code duplication [Eugenio] >> v2: >> - replace kmap_atomic() with kmap_local_page() [see previous patch] >> - fix cast warnings when build with W=1 C=1 >> >> include/linux/vringh.h | 5 +- >> drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- >> drivers/vdpa/vdpa_sim/vdpa_sim.c | 4 +- >> drivers/vhost/vringh.c | 153 +++++++++++++++++++++++------- >> 4 files changed, 127 insertions(+), 37 deletions(-) >> >> diff --git a/include/linux/vringh.h b/include/linux/vringh.h >> index 1991a02c6431..d39b9f2dcba0 100644 >> --- a/include/linux/vringh.h >> +++ b/include/linux/vringh.h >> @@ -32,6 +32,9 @@ struct vringh { >> /* Can we get away with weak barriers? */ >> bool weak_barriers; >> >> + /* Use user's VA */ >> + bool use_va; >> + >> /* Last available index we saw (ie. where we're up to). */ >> u16 last_avail_idx; >> >> @@ -279,7 +282,7 @@ void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb, >> spinlock_t *iotlb_lock); >> >> int vringh_init_iotlb(struct vringh *vrh, u64 features, >> - unsigned int num, bool weak_barriers, >> + unsigned int num, bool weak_barriers, bool use_va, >> struct vring_desc *desc, >> struct vring_avail *avail, >> struct vring_used *used); >> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> index 520646ae7fa0..dfd0e000217b 100644 >> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c >> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> @@ -2537,7 +2537,7 @@ static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) >> >> if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) >> err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features, >> - MLX5_CVQ_MAX_ENT, false, >> + MLX5_CVQ_MAX_ENT, false, false, >> (struct vring_desc *)(uintptr_t)cvq->desc_addr, >> (struct vring_avail *)(uintptr_t)cvq->driver_addr, >> (struct vring_used *)(uintptr_t)cvq->device_addr); >> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c >> index eea23c630f7c..47cdf2a1f5b8 100644 >> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c >> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c >> @@ -60,7 +60,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) >> struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; >> uint16_t last_avail_idx = vq->vring.last_avail_idx; >> >> - vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, >> + vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, false, >> (struct vring_desc *)(uintptr_t)vq->desc_addr, >> (struct vring_avail *) >> (uintptr_t)vq->driver_addr, >> @@ -92,7 +92,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim, >> vq->cb = NULL; >> vq->private = NULL; >> vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features, >> - VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL); >> + VDPASIM_QUEUE_MAX, false, false, NULL, NULL, NULL); >> >> vq->vring.notify = NULL; >> } >> diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c >> index 0ba3ef809e48..72c88519329a 100644 >> --- a/drivers/vhost/vringh.c >> +++ b/drivers/vhost/vringh.c >> @@ -1094,10 +1094,18 @@ EXPORT_SYMBOL(vringh_need_notify_kern); >> >> #if IS_REACHABLE(CONFIG_VHOST_IOTLB) >> >> +struct iotlb_vec { >> + union { >> + struct iovec *iovec; >> + struct bio_vec *bvec; >> + } iov; >> + size_t count; >> + bool is_iovec; >> +}; >> + >> static int iotlb_translate(const struct vringh *vrh, >> u64 addr, u64 len, u64 *translated, >> - struct bio_vec iov[], >> - int iov_size, u32 perm) >> + struct iotlb_vec *ivec, u32 perm) >> { >> struct vhost_iotlb_map *map; >> struct vhost_iotlb *iotlb = vrh->iotlb; >> @@ -1107,9 +1115,9 @@ static int iotlb_translate(const struct vringh *vrh, >> spin_lock(vrh->iotlb_lock); >> >> while (len > s) { >> - u64 size, pa, pfn; >> + u64 size; >> >> - if (unlikely(ret >= iov_size)) { >> + if (unlikely(ret >= ivec->count)) { >> ret = -ENOBUFS; >> break; >> } >> @@ -1124,10 +1132,22 @@ static int iotlb_translate(const struct vringh *vrh, >> } >> >> size = map->size - addr + map->start; >> - pa = map->addr + addr - map->start; >> - pfn = pa >> PAGE_SHIFT; >> - bvec_set_page(&iov[ret], pfn_to_page(pfn), min(len - s, size), >> - pa & (PAGE_SIZE - 1)); >> + if (ivec->is_iovec) { >> + struct iovec *iovec = ivec->iov.iovec; >> + >> + iovec[ret].iov_len = min(len - s, size); >> + iovec[ret].iov_base = (void __user *)(unsigned long) > >s/unsigned long/uintptr_t ? > yep, good catch! As I wrote to Jason, I think I'll take it out of the if and just declare an uintptr_t variable, since I'm using it also in the else branch. > > >> + (map->addr + addr - map->start); >> + } else { >> + u64 pa = map->addr + addr - map->start; >> + u64 pfn = pa >> PAGE_SHIFT; >> + struct bio_vec *bvec = ivec->iov.bvec; >> + >> + bvec_set_page(&bvec[ret], pfn_to_page(pfn), >> + min(len - s, size), >> + pa & (PAGE_SIZE - 1)); >> + } >> + >> s += size; >> addr += size; >> ++ret; >> @@ -1141,26 +1161,42 @@ static int iotlb_translate(const struct vringh *vrh, >> return ret; >> } >> >> +#define IOTLB_IOV_SIZE 16 > >I'm fine with defining here, but maybe it is better to isolate the >change in a previous patch or reuse another well known macro? Yep, good point! Do you have any well known macro to suggest? > >Other looks good, and I agree with Jason's comments so even if the >macro declaration is not moved: > >Acked-by: Eugenio Pérez <eperezma@redhat.com> Thanks, Stefano
On Thu, Mar 23, 2023 at 11:46 AM Stefano Garzarella <sgarzare@redhat.com> wrote: > > On Thu, Mar 23, 2023 at 09:09:14AM +0100, Eugenio Perez Martin wrote: > >On Tue, Mar 21, 2023 at 4:43 PM Stefano Garzarella <sgarzare@redhat.com> wrote: > >> > >> vDPA supports the possibility to use user VA in the iotlb messages. > >> So, let's add support for user VA in vringh to use it in the vDPA > >> simulators. > >> > >> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> > >> --- > >> > >> Notes: > >> v3: > >> - refactored avoiding code duplication [Eugenio] > >> v2: > >> - replace kmap_atomic() with kmap_local_page() [see previous patch] > >> - fix cast warnings when build with W=1 C=1 > >> > >> include/linux/vringh.h | 5 +- > >> drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- > >> drivers/vdpa/vdpa_sim/vdpa_sim.c | 4 +- > >> drivers/vhost/vringh.c | 153 +++++++++++++++++++++++------- > >> 4 files changed, 127 insertions(+), 37 deletions(-) > >> > >> diff --git a/include/linux/vringh.h b/include/linux/vringh.h > >> index 1991a02c6431..d39b9f2dcba0 100644 > >> --- a/include/linux/vringh.h > >> +++ b/include/linux/vringh.h > >> @@ -32,6 +32,9 @@ struct vringh { > >> /* Can we get away with weak barriers? */ > >> bool weak_barriers; > >> > >> + /* Use user's VA */ > >> + bool use_va; > >> + > >> /* Last available index we saw (ie. where we're up to). */ > >> u16 last_avail_idx; > >> > >> @@ -279,7 +282,7 @@ void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb, > >> spinlock_t *iotlb_lock); > >> > >> int vringh_init_iotlb(struct vringh *vrh, u64 features, > >> - unsigned int num, bool weak_barriers, > >> + unsigned int num, bool weak_barriers, bool use_va, > >> struct vring_desc *desc, > >> struct vring_avail *avail, > >> struct vring_used *used); > >> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c > >> index 520646ae7fa0..dfd0e000217b 100644 > >> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > >> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > >> @@ -2537,7 +2537,7 @@ static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) > >> > >> if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) > >> err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features, > >> - MLX5_CVQ_MAX_ENT, false, > >> + MLX5_CVQ_MAX_ENT, false, false, > >> (struct vring_desc *)(uintptr_t)cvq->desc_addr, > >> (struct vring_avail *)(uintptr_t)cvq->driver_addr, > >> (struct vring_used *)(uintptr_t)cvq->device_addr); > >> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c > >> index eea23c630f7c..47cdf2a1f5b8 100644 > >> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c > >> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c > >> @@ -60,7 +60,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) > >> struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; > >> uint16_t last_avail_idx = vq->vring.last_avail_idx; > >> > >> - vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, > >> + vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, false, > >> (struct vring_desc *)(uintptr_t)vq->desc_addr, > >> (struct vring_avail *) > >> (uintptr_t)vq->driver_addr, > >> @@ -92,7 +92,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim, > >> vq->cb = NULL; > >> vq->private = NULL; > >> vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features, > >> - VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL); > >> + VDPASIM_QUEUE_MAX, false, false, NULL, NULL, NULL); > >> > >> vq->vring.notify = NULL; > >> } > >> diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c > >> index 0ba3ef809e48..72c88519329a 100644 > >> --- a/drivers/vhost/vringh.c > >> +++ b/drivers/vhost/vringh.c > >> @@ -1094,10 +1094,18 @@ EXPORT_SYMBOL(vringh_need_notify_kern); > >> > >> #if IS_REACHABLE(CONFIG_VHOST_IOTLB) > >> > >> +struct iotlb_vec { > >> + union { > >> + struct iovec *iovec; > >> + struct bio_vec *bvec; > >> + } iov; > >> + size_t count; > >> + bool is_iovec; > >> +}; > >> + > >> static int iotlb_translate(const struct vringh *vrh, > >> u64 addr, u64 len, u64 *translated, > >> - struct bio_vec iov[], > >> - int iov_size, u32 perm) > >> + struct iotlb_vec *ivec, u32 perm) > >> { > >> struct vhost_iotlb_map *map; > >> struct vhost_iotlb *iotlb = vrh->iotlb; > >> @@ -1107,9 +1115,9 @@ static int iotlb_translate(const struct vringh *vrh, > >> spin_lock(vrh->iotlb_lock); > >> > >> while (len > s) { > >> - u64 size, pa, pfn; > >> + u64 size; > >> > >> - if (unlikely(ret >= iov_size)) { > >> + if (unlikely(ret >= ivec->count)) { > >> ret = -ENOBUFS; > >> break; > >> } > >> @@ -1124,10 +1132,22 @@ static int iotlb_translate(const struct vringh *vrh, > >> } > >> > >> size = map->size - addr + map->start; > >> - pa = map->addr + addr - map->start; > >> - pfn = pa >> PAGE_SHIFT; > >> - bvec_set_page(&iov[ret], pfn_to_page(pfn), min(len - s, size), > >> - pa & (PAGE_SIZE - 1)); > >> + if (ivec->is_iovec) { > >> + struct iovec *iovec = ivec->iov.iovec; > >> + > >> + iovec[ret].iov_len = min(len - s, size); > >> + iovec[ret].iov_base = (void __user *)(unsigned long) > > > >s/unsigned long/uintptr_t ? > > > > yep, good catch! > > As I wrote to Jason, I think I'll take it out of the if and just declare > an uintptr_t variable, since I'm using it also in the else branch. > > > > > > >> + (map->addr + addr - map->start); > >> + } else { > >> + u64 pa = map->addr + addr - map->start; > >> + u64 pfn = pa >> PAGE_SHIFT; > >> + struct bio_vec *bvec = ivec->iov.bvec; > >> + > >> + bvec_set_page(&bvec[ret], pfn_to_page(pfn), > >> + min(len - s, size), > >> + pa & (PAGE_SIZE - 1)); > >> + } > >> + > >> s += size; > >> addr += size; > >> ++ret; > >> @@ -1141,26 +1161,42 @@ static int iotlb_translate(const struct vringh *vrh, > >> return ret; > >> } > >> > >> +#define IOTLB_IOV_SIZE 16 > > > >I'm fine with defining here, but maybe it is better to isolate the > >change in a previous patch or reuse another well known macro? > > Yep, good point! > > Do you have any well known macro to suggest? > Not really, 16 seems like a convenience value here actually :). Maybe replace _SIZE with _STRIDE or similar? I keep the Acked-by even if the final name is IOTLB_IOV_SIZE though. Thanks!
On Thu, Mar 23, 2023 at 03:43:34PM +0100, Eugenio Perez Martin wrote: >On Thu, Mar 23, 2023 at 11:46 AM Stefano Garzarella <sgarzare@redhat.com> wrote: >> >> On Thu, Mar 23, 2023 at 09:09:14AM +0100, Eugenio Perez Martin wrote: >> >On Tue, Mar 21, 2023 at 4:43 PM Stefano Garzarella <sgarzare@redhat.com> wrote: >> >> >> >> vDPA supports the possibility to use user VA in the iotlb messages. >> >> So, let's add support for user VA in vringh to use it in the vDPA >> >> simulators. >> >> >> >> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> >> >> --- >> >> >> >> Notes: >> >> v3: >> >> - refactored avoiding code duplication [Eugenio] >> >> v2: >> >> - replace kmap_atomic() with kmap_local_page() [see previous patch] >> >> - fix cast warnings when build with W=1 C=1 >> >> >> >> include/linux/vringh.h | 5 +- >> >> drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- >> >> drivers/vdpa/vdpa_sim/vdpa_sim.c | 4 +- >> >> drivers/vhost/vringh.c | 153 +++++++++++++++++++++++------- >> >> 4 files changed, 127 insertions(+), 37 deletions(-) >> >> >> >> diff --git a/include/linux/vringh.h b/include/linux/vringh.h >> >> index 1991a02c6431..d39b9f2dcba0 100644 >> >> --- a/include/linux/vringh.h >> >> +++ b/include/linux/vringh.h >> >> @@ -32,6 +32,9 @@ struct vringh { >> >> /* Can we get away with weak barriers? */ >> >> bool weak_barriers; >> >> >> >> + /* Use user's VA */ >> >> + bool use_va; >> >> + >> >> /* Last available index we saw (ie. where we're up to). */ >> >> u16 last_avail_idx; >> >> >> >> @@ -279,7 +282,7 @@ void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb, >> >> spinlock_t *iotlb_lock); >> >> >> >> int vringh_init_iotlb(struct vringh *vrh, u64 features, >> >> - unsigned int num, bool weak_barriers, >> >> + unsigned int num, bool weak_barriers, bool use_va, >> >> struct vring_desc *desc, >> >> struct vring_avail *avail, >> >> struct vring_used *used); >> >> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> >> index 520646ae7fa0..dfd0e000217b 100644 >> >> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c >> >> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> >> @@ -2537,7 +2537,7 @@ static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) >> >> >> >> if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) >> >> err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features, >> >> - MLX5_CVQ_MAX_ENT, false, >> >> + MLX5_CVQ_MAX_ENT, false, false, >> >> (struct vring_desc *)(uintptr_t)cvq->desc_addr, >> >> (struct vring_avail *)(uintptr_t)cvq->driver_addr, >> >> (struct vring_used *)(uintptr_t)cvq->device_addr); >> >> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c >> >> index eea23c630f7c..47cdf2a1f5b8 100644 >> >> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c >> >> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c >> >> @@ -60,7 +60,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) >> >> struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; >> >> uint16_t last_avail_idx = vq->vring.last_avail_idx; >> >> >> >> - vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, >> >> + vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, false, >> >> (struct vring_desc *)(uintptr_t)vq->desc_addr, >> >> (struct vring_avail *) >> >> (uintptr_t)vq->driver_addr, >> >> @@ -92,7 +92,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim, >> >> vq->cb = NULL; >> >> vq->private = NULL; >> >> vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features, >> >> - VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL); >> >> + VDPASIM_QUEUE_MAX, false, false, NULL, NULL, NULL); >> >> >> >> vq->vring.notify = NULL; >> >> } >> >> diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c >> >> index 0ba3ef809e48..72c88519329a 100644 >> >> --- a/drivers/vhost/vringh.c >> >> +++ b/drivers/vhost/vringh.c >> >> @@ -1094,10 +1094,18 @@ EXPORT_SYMBOL(vringh_need_notify_kern); >> >> >> >> #if IS_REACHABLE(CONFIG_VHOST_IOTLB) >> >> >> >> +struct iotlb_vec { >> >> + union { >> >> + struct iovec *iovec; >> >> + struct bio_vec *bvec; >> >> + } iov; >> >> + size_t count; >> >> + bool is_iovec; >> >> +}; >> >> + >> >> static int iotlb_translate(const struct vringh *vrh, >> >> u64 addr, u64 len, u64 *translated, >> >> - struct bio_vec iov[], >> >> - int iov_size, u32 perm) >> >> + struct iotlb_vec *ivec, u32 perm) >> >> { >> >> struct vhost_iotlb_map *map; >> >> struct vhost_iotlb *iotlb = vrh->iotlb; >> >> @@ -1107,9 +1115,9 @@ static int iotlb_translate(const struct vringh *vrh, >> >> spin_lock(vrh->iotlb_lock); >> >> >> >> while (len > s) { >> >> - u64 size, pa, pfn; >> >> + u64 size; >> >> >> >> - if (unlikely(ret >= iov_size)) { >> >> + if (unlikely(ret >= ivec->count)) { >> >> ret = -ENOBUFS; >> >> break; >> >> } >> >> @@ -1124,10 +1132,22 @@ static int iotlb_translate(const struct vringh *vrh, >> >> } >> >> >> >> size = map->size - addr + map->start; >> >> - pa = map->addr + addr - map->start; >> >> - pfn = pa >> PAGE_SHIFT; >> >> - bvec_set_page(&iov[ret], pfn_to_page(pfn), min(len - s, size), >> >> - pa & (PAGE_SIZE - 1)); >> >> + if (ivec->is_iovec) { >> >> + struct iovec *iovec = ivec->iov.iovec; >> >> + >> >> + iovec[ret].iov_len = min(len - s, size); >> >> + iovec[ret].iov_base = (void __user *)(unsigned long) >> > >> >s/unsigned long/uintptr_t ? >> > >> >> yep, good catch! >> >> As I wrote to Jason, I think I'll take it out of the if and just declare >> an uintptr_t variable, since I'm using it also in the else branch. >> >> > >> > >> >> + (map->addr + addr - map->start); >> >> + } else { >> >> + u64 pa = map->addr + addr - map->start; >> >> + u64 pfn = pa >> PAGE_SHIFT; >> >> + struct bio_vec *bvec = ivec->iov.bvec; >> >> + >> >> + bvec_set_page(&bvec[ret], pfn_to_page(pfn), >> >> + min(len - s, size), >> >> + pa & (PAGE_SIZE - 1)); >> >> + } >> >> + >> >> s += size; >> >> addr += size; >> >> ++ret; >> >> @@ -1141,26 +1161,42 @@ static int iotlb_translate(const struct vringh *vrh, >> >> return ret; >> >> } >> >> >> >> +#define IOTLB_IOV_SIZE 16 >> > >> >I'm fine with defining here, but maybe it is better to isolate the >> >change in a previous patch or reuse another well known macro? >> >> Yep, good point! >> >> Do you have any well known macro to suggest? >> > >Not really, 16 seems like a convenience value here actually :). Maybe >replace _SIZE with _STRIDE or similar? Ack, I will add IOTLB_IOV_STRIDE in a preparation patch before this one. > >I keep the Acked-by even if the final name is IOTLB_IOV_SIZE though. Thanks, I changed a bit this patch following Jason's and your suggestions. I'd like an explicit Acked-by on the next version if it is okay with you. Thanks, Stefano
diff --git a/include/linux/vringh.h b/include/linux/vringh.h index 1991a02c6431..d39b9f2dcba0 100644 --- a/include/linux/vringh.h +++ b/include/linux/vringh.h @@ -32,6 +32,9 @@ struct vringh { /* Can we get away with weak barriers? */ bool weak_barriers; + /* Use user's VA */ + bool use_va; + /* Last available index we saw (ie. where we're up to). */ u16 last_avail_idx; @@ -279,7 +282,7 @@ void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb, spinlock_t *iotlb_lock); int vringh_init_iotlb(struct vringh *vrh, u64 features, - unsigned int num, bool weak_barriers, + unsigned int num, bool weak_barriers, bool use_va, struct vring_desc *desc, struct vring_avail *avail, struct vring_used *used); diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c index 520646ae7fa0..dfd0e000217b 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c @@ -2537,7 +2537,7 @@ static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features, - MLX5_CVQ_MAX_ENT, false, + MLX5_CVQ_MAX_ENT, false, false, (struct vring_desc *)(uintptr_t)cvq->desc_addr, (struct vring_avail *)(uintptr_t)cvq->driver_addr, (struct vring_used *)(uintptr_t)cvq->device_addr); diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c index eea23c630f7c..47cdf2a1f5b8 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -60,7 +60,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; uint16_t last_avail_idx = vq->vring.last_avail_idx; - vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, + vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, true, false, (struct vring_desc *)(uintptr_t)vq->desc_addr, (struct vring_avail *) (uintptr_t)vq->driver_addr, @@ -92,7 +92,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim, vq->cb = NULL; vq->private = NULL; vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features, - VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL); + VDPASIM_QUEUE_MAX, false, false, NULL, NULL, NULL); vq->vring.notify = NULL; } diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c index 0ba3ef809e48..72c88519329a 100644 --- a/drivers/vhost/vringh.c +++ b/drivers/vhost/vringh.c @@ -1094,10 +1094,18 @@ EXPORT_SYMBOL(vringh_need_notify_kern); #if IS_REACHABLE(CONFIG_VHOST_IOTLB) +struct iotlb_vec { + union { + struct iovec *iovec; + struct bio_vec *bvec; + } iov; + size_t count; + bool is_iovec; +}; + static int iotlb_translate(const struct vringh *vrh, u64 addr, u64 len, u64 *translated, - struct bio_vec iov[], - int iov_size, u32 perm) + struct iotlb_vec *ivec, u32 perm) { struct vhost_iotlb_map *map; struct vhost_iotlb *iotlb = vrh->iotlb; @@ -1107,9 +1115,9 @@ static int iotlb_translate(const struct vringh *vrh, spin_lock(vrh->iotlb_lock); while (len > s) { - u64 size, pa, pfn; + u64 size; - if (unlikely(ret >= iov_size)) { + if (unlikely(ret >= ivec->count)) { ret = -ENOBUFS; break; } @@ -1124,10 +1132,22 @@ static int iotlb_translate(const struct vringh *vrh, } size = map->size - addr + map->start; - pa = map->addr + addr - map->start; - pfn = pa >> PAGE_SHIFT; - bvec_set_page(&iov[ret], pfn_to_page(pfn), min(len - s, size), - pa & (PAGE_SIZE - 1)); + if (ivec->is_iovec) { + struct iovec *iovec = ivec->iov.iovec; + + iovec[ret].iov_len = min(len - s, size); + iovec[ret].iov_base = (void __user *)(unsigned long) + (map->addr + addr - map->start); + } else { + u64 pa = map->addr + addr - map->start; + u64 pfn = pa >> PAGE_SHIFT; + struct bio_vec *bvec = ivec->iov.bvec; + + bvec_set_page(&bvec[ret], pfn_to_page(pfn), + min(len - s, size), + pa & (PAGE_SIZE - 1)); + } + s += size; addr += size; ++ret; @@ -1141,26 +1161,42 @@ static int iotlb_translate(const struct vringh *vrh, return ret; } +#define IOTLB_IOV_SIZE 16 + static inline int copy_from_iotlb(const struct vringh *vrh, void *dst, void *src, size_t len) { + struct iotlb_vec ivec; + union { + struct iovec iovec[IOTLB_IOV_SIZE]; + struct bio_vec bvec[IOTLB_IOV_SIZE]; + } iov; u64 total_translated = 0; + ivec.iov.iovec = iov.iovec; + ivec.count = IOTLB_IOV_SIZE; + ivec.is_iovec = vrh->use_va; + while (total_translated < len) { - struct bio_vec iov[16]; struct iov_iter iter; u64 translated; int ret; ret = iotlb_translate(vrh, (u64)(uintptr_t)src, len - total_translated, &translated, - iov, ARRAY_SIZE(iov), VHOST_MAP_RO); + &ivec, VHOST_MAP_RO); if (ret == -ENOBUFS) - ret = ARRAY_SIZE(iov); + ret = IOTLB_IOV_SIZE; else if (ret < 0) return ret; - iov_iter_bvec(&iter, ITER_SOURCE, iov, ret, translated); + if (ivec.is_iovec) { + iov_iter_init(&iter, ITER_SOURCE, ivec.iov.iovec, ret, + translated); + } else { + iov_iter_bvec(&iter, ITER_SOURCE, ivec.iov.bvec, ret, + translated); + } ret = copy_from_iter(dst, translated, &iter); if (ret < 0) @@ -1177,23 +1213,37 @@ static inline int copy_from_iotlb(const struct vringh *vrh, void *dst, static inline int copy_to_iotlb(const struct vringh *vrh, void *dst, void *src, size_t len) { + struct iotlb_vec ivec; + union { + struct iovec iovec[IOTLB_IOV_SIZE]; + struct bio_vec bvec[IOTLB_IOV_SIZE]; + } iov; u64 total_translated = 0; + ivec.iov.iovec = iov.iovec; + ivec.count = IOTLB_IOV_SIZE; + ivec.is_iovec = vrh->use_va; + while (total_translated < len) { - struct bio_vec iov[16]; struct iov_iter iter; u64 translated; int ret; ret = iotlb_translate(vrh, (u64)(uintptr_t)dst, len - total_translated, &translated, - iov, ARRAY_SIZE(iov), VHOST_MAP_WO); + &ivec, VHOST_MAP_WO); if (ret == -ENOBUFS) - ret = ARRAY_SIZE(iov); + ret = IOTLB_IOV_SIZE; else if (ret < 0) return ret; - iov_iter_bvec(&iter, ITER_DEST, iov, ret, translated); + if (ivec.is_iovec) { + iov_iter_init(&iter, ITER_DEST, ivec.iov.iovec, ret, + translated); + } else { + iov_iter_bvec(&iter, ITER_DEST, ivec.iov.bvec, ret, + translated); + } ret = copy_to_iter(src, translated, &iter); if (ret < 0) @@ -1210,20 +1260,37 @@ static inline int copy_to_iotlb(const struct vringh *vrh, void *dst, static inline int getu16_iotlb(const struct vringh *vrh, u16 *val, const __virtio16 *p) { - struct bio_vec iov; - void *kaddr, *from; + struct iotlb_vec ivec; + union { + struct iovec iovec[1]; + struct bio_vec bvec[1]; + } iov; + __virtio16 tmp; int ret; + ivec.iov.iovec = iov.iovec; + ivec.count = 1; + ivec.is_iovec = vrh->use_va; + /* Atomic read is needed for getu16 */ - ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL, - &iov, 1, VHOST_MAP_RO); + ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), + NULL, &ivec, VHOST_MAP_RO); if (ret < 0) return ret; - kaddr = kmap_local_page(iov.bv_page); - from = kaddr + iov.bv_offset; - *val = vringh16_to_cpu(vrh, READ_ONCE(*(__virtio16 *)from)); - kunmap_local(kaddr); + if (ivec.is_iovec) { + ret = __get_user(tmp, (__virtio16 __user *)ivec.iov.iovec[0].iov_base); + if (ret) + return ret; + } else { + void *kaddr = kmap_local_page(ivec.iov.bvec[0].bv_page); + void *from = kaddr + ivec.iov.bvec[0].bv_offset; + + tmp = READ_ONCE(*(__virtio16 *)from); + kunmap_local(kaddr); + } + + *val = vringh16_to_cpu(vrh, tmp); return 0; } @@ -1231,20 +1298,37 @@ static inline int getu16_iotlb(const struct vringh *vrh, static inline int putu16_iotlb(const struct vringh *vrh, __virtio16 *p, u16 val) { - struct bio_vec iov; - void *kaddr, *to; + struct iotlb_vec ivec; + union { + struct iovec iovec; + struct bio_vec bvec; + } iov; + __virtio16 tmp; int ret; + ivec.iov.iovec = &iov.iovec; + ivec.count = 1; + ivec.is_iovec = vrh->use_va; + /* Atomic write is needed for putu16 */ - ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL, - &iov, 1, VHOST_MAP_WO); + ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), + NULL, &ivec, VHOST_MAP_RO); if (ret < 0) return ret; - kaddr = kmap_local_page(iov.bv_page); - to = kaddr + iov.bv_offset; - WRITE_ONCE(*(__virtio16 *)to, cpu_to_vringh16(vrh, val)); - kunmap_local(kaddr); + tmp = cpu_to_vringh16(vrh, val); + + if (ivec.is_iovec) { + ret = __put_user(tmp, (__virtio16 __user *)ivec.iov.iovec[0].iov_base); + if (ret) + return ret; + } else { + void *kaddr = kmap_local_page(ivec.iov.bvec[0].bv_page); + void *to = kaddr + ivec.iov.bvec[0].bv_offset; + + WRITE_ONCE(*(__virtio16 *)to, tmp); + kunmap_local(kaddr); + } return 0; } @@ -1306,6 +1390,7 @@ static inline int putused_iotlb(const struct vringh *vrh, * @features: the feature bits for this ring. * @num: the number of elements. * @weak_barriers: true if we only need memory barriers, not I/O. + * @use_va: true if IOTLB contains user VA * @desc: the userpace descriptor pointer. * @avail: the userpace avail pointer. * @used: the userpace used pointer. @@ -1313,11 +1398,13 @@ static inline int putused_iotlb(const struct vringh *vrh, * Returns an error if num is invalid. */ int vringh_init_iotlb(struct vringh *vrh, u64 features, - unsigned int num, bool weak_barriers, + unsigned int num, bool weak_barriers, bool use_va, struct vring_desc *desc, struct vring_avail *avail, struct vring_used *used) { + vrh->use_va = use_va; + return vringh_init_kern(vrh, features, num, weak_barriers, desc, avail, used); }
vDPA supports the possibility to use user VA in the iotlb messages. So, let's add support for user VA in vringh to use it in the vDPA simulators. Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> --- Notes: v3: - refactored avoiding code duplication [Eugenio] v2: - replace kmap_atomic() with kmap_local_page() [see previous patch] - fix cast warnings when build with W=1 C=1 include/linux/vringh.h | 5 +- drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- drivers/vdpa/vdpa_sim/vdpa_sim.c | 4 +- drivers/vhost/vringh.c | 153 +++++++++++++++++++++++------- 4 files changed, 127 insertions(+), 37 deletions(-)