On Thu, Dec 7, 2023 at 7:51 PM Si-Wei Liu <si-wei....@oracle.com> wrote:
>
> Then it's possible to specify ASID when calling the DMA
> batching API. If the ASID to work on doesn't align with
> the ASID for ongoing transaction, the API will fail the
> request and return negative, and the transaction will
> remain intact as if no failed request ever had occured.
>
> Signed-off-by: Si-Wei Liu <si-wei....@oracle.com>
> ---
> hw/virtio/vhost-vdpa.c | 25 +++++++++++++++++++------
> include/hw/virtio/vhost-vdpa.h | 1 +
> net/vhost-vdpa.c | 1 +
> 3 files changed, 21 insertions(+), 6 deletions(-)
>
> diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> index d3f5721..b7896a8 100644
> --- a/hw/virtio/vhost-vdpa.c
> +++ b/hw/virtio/vhost-vdpa.c
> @@ -189,15 +189,25 @@ static bool vhost_vdpa_map_batch_begin(VhostVDPAShared
> *s, uint32_t asid)
>
> static int vhost_vdpa_dma_batch_begin_once(VhostVDPAShared *s, uint32_t asid)
> {
> - if (!(s->backend_cap & (0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH)) ||
> - s->iotlb_batch_begin_sent) {
> + if (!(s->backend_cap & (0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH))) {
> return 0;
> }
>
> - if (vhost_vdpa_map_batch_begin(s, asid)) {
> - s->iotlb_batch_begin_sent = true;
> + if (s->iotlb_batch_begin_sent && s->iotlb_batch_asid != asid) {
> + return -1;
> + }
> +
> + if (s->iotlb_batch_begin_sent) {
> + return 0;
> }
>
> + if (!vhost_vdpa_map_batch_begin(s, asid)) {
> + return 0;
> + }
> +
> + s->iotlb_batch_begin_sent = true;
> + s->iotlb_batch_asid = asid;
> +
> return 0;
> }
>
> @@ -237,10 +247,13 @@ static int
> vhost_vdpa_dma_batch_end_once(VhostVDPAShared *s, uint32_t asid)
> return 0;
> }
>
> - if (vhost_vdpa_dma_batch_end(s, asid)) {
> - s->iotlb_batch_begin_sent = false;
> + if (!vhost_vdpa_dma_batch_end(s, asid)) {
> + return 0;
> }
>
> + s->iotlb_batch_begin_sent = false;
> + s->iotlb_batch_asid = -1;
If we define -1 as "not in batch", iotlb_batch_begin_sent is
redundant. Can we "#define IOTLB_NOT_IN_BATCH -1" and remove
iotlb_batch_begin_sent?
> +
> return 0;
> }
>
> diff --git a/include/hw/virtio/vhost-vdpa.h b/include/hw/virtio/vhost-vdpa.h
> index 0fe0f60..219316f 100644
> --- a/include/hw/virtio/vhost-vdpa.h
> +++ b/include/hw/virtio/vhost-vdpa.h
> @@ -61,6 +61,7 @@ typedef struct vhost_vdpa_shared {
> bool map_thread_enabled;
>
> bool iotlb_batch_begin_sent;
> + uint32_t iotlb_batch_asid;
>
> /*
> * The memory listener has been registered, so DMA maps have been sent to
> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> index e9b96ed..bc72345 100644
> --- a/net/vhost-vdpa.c
> +++ b/net/vhost-vdpa.c
> @@ -1933,6 +1933,7 @@ static NetClientState
> *net_vhost_vdpa_init(NetClientState *peer,
> s->vhost_vdpa.shared->device_fd = vdpa_device_fd;
> s->vhost_vdpa.shared->iova_range = iova_range;
> s->vhost_vdpa.shared->shadow_data = svq;
> + s->vhost_vdpa.shared->iotlb_batch_asid = -1;
> s->vhost_vdpa.shared->refcnt++;
> } else if (!is_datapath) {
> s->cvq_cmd_out_buffer = mmap(NULL, vhost_vdpa_net_cvq_cmd_page_len(),
> --
> 1.8.3.1
>
