Re: [PATCH v2 08/17] vdpa_sim: add supported_features field in vdpasim_dev_attr

[Jason Wang]

On 2020/11/26 下午10:49, Stefano Garzarella wrote:

Introduce a new VDPASIM_FEATURES macro with the generic features
supported by the vDPA simulator, and VDPASIM_NET_FEATURES macro with
vDPA-net features.

Add 'supported_features' field in vdpasim_dev_attr, to allow devices
to specify their features.

Co-developed-by: Max Gurtovoy <mgurto...@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurto...@nvidia.com>
Signed-off-by: Stefano Garzarella <sgarz...@redhat.com>
---
  drivers/vdpa/vdpa_sim/vdpa_sim.c | 29 ++++++++++++++++++-----------
  1 file changed, 18 insertions(+), 11 deletions(-)

Acked-by: Jason Wang <jasow...@redhat.com>

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index 393b54a9f0e4..36677fc3631b 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -49,12 +49,15 @@ struct vdpasim_virtqueue {
  #define VDPASIM_VQ_NUM 0x2
  #define VDPASIM_NAME "vdpasim-netdev"

-static u64 vdpasim_features = (1ULL << VIRTIO_F_ANY_LAYOUT) |

-                             (1ULL << VIRTIO_F_VERSION_1)  |
-                             (1ULL << VIRTIO_F_ACCESS_PLATFORM) |
-                             (1ULL << VIRTIO_NET_F_MAC);
+#define VDPASIM_FEATURES       ((1ULL << VIRTIO_F_ANY_LAYOUT) | \
+                                (1ULL << VIRTIO_F_VERSION_1)  | \
+                                (1ULL << VIRTIO_F_ACCESS_PLATFORM))
+
+#define VDPASIM_NET_FEATURES   (VDPASIM_FEATURES | \
+                                (1ULL << VIRTIO_NET_F_MAC))

struct vdpasim_dev_attr {

+       u64 supported_features;
        int nvqs;
        u32 id;
  };
@@ -112,7 +115,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, 
unsigned int idx)
  {
        struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];

- vringh_init_iotlb(&vq->vring, vdpasim_features,

+       vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features,
                          VDPASIM_QUEUE_MAX, false,
                          (struct vring_desc *)(uintptr_t)vq->desc_addr,
                          (struct vring_avail *)
@@ -121,7 +124,8 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, 
unsigned int idx)
                          (uintptr_t)vq->device_addr);
  }

-static void vdpasim_vq_reset(struct vdpasim_virtqueue *vq)

+static void vdpasim_vq_reset(struct vdpasim *vdpasim,
+                            struct vdpasim_virtqueue *vq)
  {
        vq->ready = false;
        vq->desc_addr = 0;
@@ -129,8 +133,8 @@ static void vdpasim_vq_reset(struct vdpasim_virtqueue *vq)
        vq->device_addr = 0;
        vq->cb = NULL;
        vq->private = NULL;
-       vringh_init_iotlb(&vq->vring, vdpasim_features, VDPASIM_QUEUE_MAX,
-                         false, NULL, NULL, NULL);
+       vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features,
+                         VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL);
  }

static void vdpasim_reset(struct vdpasim *vdpasim)

@@ -138,7 +142,7 @@ static void vdpasim_reset(struct vdpasim *vdpasim)
        int i;

for (i = 0; i < vdpasim->dev_attr.nvqs; i++)

-               vdpasim_vq_reset(&vdpasim->vqs[i]);
+               vdpasim_vq_reset(vdpasim, &vdpasim->vqs[i]);

spin_lock(&vdpasim->iommu_lock);

        vhost_iotlb_reset(vdpasim->iommu);
@@ -498,7 +502,9 @@ static u32 vdpasim_get_vq_align(struct vdpa_device *vdpa)

static u64 vdpasim_get_features(struct vdpa_device *vdpa)

  {
-       return vdpasim_features;
+       struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+       return vdpasim->dev_attr.supported_features;
  }

static int vdpasim_set_features(struct vdpa_device *vdpa, u64 features)

@@ -510,7 +516,7 @@ static int vdpasim_set_features(struct vdpa_device *vdpa, 
u64 features)
        if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))
                return -EINVAL;

- vdpasim->features = features & vdpasim_features;

+       vdpasim->features = features & vdpasim->dev_attr.supported_features;

/* We generally only know whether guest is using the legacy interface

         * here, so generally that's the earliest we can set config fields.
@@ -722,6 +728,7 @@ static int __init vdpasim_dev_init(void)
        struct vdpasim_dev_attr dev_attr = {};

dev_attr.id = VIRTIO_ID_NET;

+       dev_attr.supported_features = VDPASIM_NET_FEATURES;
        dev_attr.nvqs = VDPASIM_VQ_NUM;

vdpasim_dev = vdpasim_create(&dev_attr);