Re: [Qemu-devel] [PATCH v7 1/1] crypto: add virtio-crypto driver

[Halil Pasic]

On 12/14/2016 12:50 PM, Gonglei wrote:
> diff --git a/drivers/crypto/virtio/virtio_crypto_core.c 
> b/drivers/crypto/virtio/virtio_crypto_core.c
> new file mode 100644
> index 0000000..c0854a1
> --- /dev/null
> +++ b/drivers/crypto/virtio/virtio_crypto_core.c
> @@ -0,0 +1,474 @@
[..]
> +
> +static void virtcrypto_dataq_callback(struct virtqueue *vq)
> +{
> +     struct virtio_crypto *vcrypto = vq->vdev->priv;
> +     struct virtio_crypto_request *vc_req;
> +     unsigned long flags;
> +     unsigned int len;
> +     struct ablkcipher_request *ablk_req;
> +     int error;
> +
> +     spin_lock_irqsave(&vcrypto->lock, flags);

Would it make sense to use a per virtqueue lock
like in virtio_blk for example instead of locking on the whole
device? OK, it seems you use only one dataqueue, so it
may not be that relevant.

> +     do {
> +             virtqueue_disable_cb(vq);
> +             while ((vc_req = virtqueue_get_buf(vq, &len)) != NULL) {
> +                     if (vc_req->type == VIRTIO_CRYPTO_SYM_OP_CIPHER) {
> +                             switch (vc_req->status) {
> +                             case VIRTIO_CRYPTO_OK:
> +                                     error = 0;
> +                                     break;
> +                             case VIRTIO_CRYPTO_INVSESS:
> +                             case VIRTIO_CRYPTO_ERR:
> +                                     error = -EINVAL;
> +                                     break;
> +                             case VIRTIO_CRYPTO_BADMSG:
> +                                     error = -EBADMSG;
> +                                     break;
> +                             default:
> +                                     error = -EIO;
> +                                     break;
> +                             }
> +                             ablk_req = vc_req->ablkcipher_req;
> +                             virtcrypto_clear_request(vc_req);
> +
> +                             spin_unlock_irqrestore(&vcrypto->lock, flags);
> +                             /* Finish the encrypt or decrypt process */
> +                             ablk_req->base.complete(&ablk_req->base, error);
> +                             spin_lock_irqsave(&vcrypto->lock, flags);
> +                     }
> +             }
> +     } while (!virtqueue_enable_cb(vq));
> +     spin_unlock_irqrestore(&vcrypto->lock, flags);
> +}