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)
+ (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);
}
--
2.39.2On 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 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
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 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
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