[PATCH 1/6] virtio: wrap find_vqs

[PATCH 1/6] virtio: wrap find_vqs

[Michael S. Tsirkin]

We are going to add more parameters to find_vqs, let's wrap the call so
we don't need to tweak all drivers every time.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/block/virtio_blk.c                 | 3 +--
 drivers/char/virtio_console.c              | 6 +++---
 drivers/crypto/virtio/virtio_crypto_core.c | 3 +--
 drivers/gpu/drm/virtio/virtgpu_kms.c       | 3 +--
 drivers/net/caif/caif_virtio.c             | 3 +--
 drivers/net/virtio_net.c                   | 3 +--
 drivers/rpmsg/virtio_rpmsg_bus.c           | 2 +-
 drivers/scsi/virtio_scsi.c                 | 3 +--
 drivers/virtio/virtio_balloon.c            | 3 +--
 drivers/virtio/virtio_input.c              | 3 +--
 include/linux/virtio_config.h              | 9 +++++++++
 net/vmw_vsock/virtio_transport.c           | 6 +++---
 12 files changed, 24 insertions(+), 23 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 1d4c9f8..c08c30c 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -455,8 +455,7 @@ static int init_vq(struct virtio_blk *vblk)
 	}
 
 	/* Discover virtqueues and write information to configuration.  */
-	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names,
-			&desc);
+	err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc);
 	if (err)
 		goto out;
 
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index e9b7e0b..5da4c8e 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1945,9 +1945,9 @@ static int init_vqs(struct ports_device *portdev)
 		}
 	}
 	/* Find the queues. */
-	err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
-					      io_callbacks,
-					      (const char **)io_names, NULL);
+	err = virtio_find_vqs(portdev->vdev, nr_queues, vqs,
+			      io_callbacks,
+			      (const char **)io_names, NULL);
 	if (err)
 		goto free;
 
diff --git a/drivers/crypto/virtio/virtio_crypto_core.c b/drivers/crypto/virtio/virtio_crypto_core.c
index 21472e4..a111cd72 100644
--- a/drivers/crypto/virtio/virtio_crypto_core.c
+++ b/drivers/crypto/virtio/virtio_crypto_core.c
@@ -119,8 +119,7 @@ static int virtcrypto_find_vqs(struct virtio_crypto *vi)
 		names[i] = vi->data_vq[i].name;
 	}
 
-	ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
-					 names, NULL);
+	ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
 	if (ret)
 		goto err_find;
 
diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c
index 4918668..1e1c90b 100644
--- a/drivers/gpu/drm/virtio/virtgpu_kms.c
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -175,8 +175,7 @@ int virtio_gpu_driver_load(struct drm_device *dev, unsigned long flags)
 	DRM_INFO("virgl 3d acceleration not supported by guest\n");
 #endif
 
-	ret = vgdev->vdev->config->find_vqs(vgdev->vdev, 2, vqs,
-					    callbacks, names, NULL);
+	ret = virtio_find_vqs(vgdev->vdev, 2, vqs, callbacks, names, NULL);
 	if (ret) {
 		DRM_ERROR("failed to find virt queues\n");
 		goto err_vqs;
diff --git a/drivers/net/caif/caif_virtio.c b/drivers/net/caif/caif_virtio.c
index bc0eb47..6122768 100644
--- a/drivers/net/caif/caif_virtio.c
+++ b/drivers/net/caif/caif_virtio.c
@@ -679,8 +679,7 @@ static int cfv_probe(struct virtio_device *vdev)
 		goto err;
 
 	/* Get the TX virtio ring. This is a "guest side vring". */
-	err = vdev->config->find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs, &names,
-			NULL);
+	err = virtio_find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs, &names, NULL);
 	if (err)
 		goto err;
 
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index ea9890d..6802169 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -2079,8 +2079,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
 		names[txq2vq(i)] = vi->sq[i].name;
 	}
 
-	ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
-					 names, NULL);
+	ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
 	if (ret)
 		goto err_find;
 
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 5e66e08..f7cade0 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -869,7 +869,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
 	init_waitqueue_head(&vrp->sendq);
 
 	/* We expect two virtqueues, rx and tx (and in this order) */
-	err = vdev->config->find_vqs(vdev, 2, vqs, vq_cbs, names, NULL);
+	err = virtio_find_vqs(vdev, 2, vqs, vq_cbs, names, NULL);
 	if (err)
 		goto free_vrp;
 
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 939c47d..e9222dc 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -870,8 +870,7 @@ static int virtscsi_init(struct virtio_device *vdev,
 	}
 
 	/* Discover virtqueues and write information to configuration.  */
-	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names,
-			&desc);
+	err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc);
 	if (err)
 		goto out;
 
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 34adf9b..408c174 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -418,8 +418,7 @@ static int init_vqs(struct virtio_balloon *vb)
 	 * optionally stat.
 	 */
 	nvqs = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ) ? 3 : 2;
-	err = vb->vdev->config->find_vqs(vb->vdev, nvqs, vqs, callbacks, names,
-			NULL);
+	err = virtio_find_vqs(vb->vdev, nvqs, vqs, callbacks, names, NULL);
 	if (err)
 		return err;
 
diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c
index 79f1293..3a0468f 100644
--- a/drivers/virtio/virtio_input.c
+++ b/drivers/virtio/virtio_input.c
@@ -173,8 +173,7 @@ static int virtinput_init_vqs(struct virtio_input *vi)
 	static const char * const names[] = { "events", "status" };
 	int err;
 
-	err = vi->vdev->config->find_vqs(vi->vdev, 2, vqs, cbs, names,
-			NULL);
+	err = virtio_find_vqs(vi->vdev, 2, vqs, cbs, names, NULL);
 	if (err)
 		return err;
 	vi->evt = vqs[0];
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 8355bab..47f3d80 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -179,6 +179,15 @@ struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev,
 	return vq;
 }
 
+static inline
+int virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+			struct virtqueue *vqs[], vq_callback_t *callbacks[],
+			const char * const names[],
+			struct irq_affinity *desc)
+{
+	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, desc);
+}
+
 /**
  * virtio_device_ready - enable vq use in probe function
  * @vdev: the device
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 68675a1..97e26e2 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -573,9 +573,9 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
 
 	vsock->vdev = vdev;
 
-	ret = vsock->vdev->config->find_vqs(vsock->vdev, VSOCK_VQ_MAX,
-					    vsock->vqs, callbacks, names,
-					    NULL);
+	ret = virtio_find_vqs(vsock->vdev, VSOCK_VQ_MAX,
+			      vsock->vqs, callbacks, names,
+			      NULL);
 	if (ret < 0)
 		goto out;
 
-- 
MST

RE: [PATCH 1/6] virtio: wrap find_vqs

[Gonglei (Arei)]

> -----Original Message-----
> From: Michael S. Tsirkin [mailto:mst@redhat.com]
> Sent: Thursday, March 30, 2017 4:49 AM
> Subject: [PATCH 1/6] virtio: wrap find_vqs
> 
> We are going to add more parameters to find_vqs, let's wrap the call so
> we don't need to tweak all drivers every time.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>  drivers/block/virtio_blk.c                 | 3 +--
>  drivers/char/virtio_console.c              | 6 +++---
>  drivers/crypto/virtio/virtio_crypto_core.c | 3 +--
>  drivers/gpu/drm/virtio/virtgpu_kms.c       | 3 +--
>  drivers/net/caif/caif_virtio.c             | 3 +--
>  drivers/net/virtio_net.c                   | 3 +--
>  drivers/rpmsg/virtio_rpmsg_bus.c           | 2 +-
>  drivers/scsi/virtio_scsi.c                 | 3 +--
>  drivers/virtio/virtio_balloon.c            | 3 +--
>  drivers/virtio/virtio_input.c              | 3 +--
>  include/linux/virtio_config.h              | 9 +++++++++
>  net/vmw_vsock/virtio_transport.c           | 6 +++---
>  12 files changed, 24 insertions(+), 23 deletions(-)
> 

Acked-by: Gonglei <arei.gonglei@huawei.com>


> diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
> index 1d4c9f8..c08c30c 100644
> --- a/drivers/block/virtio_blk.c
> +++ b/drivers/block/virtio_blk.c
> @@ -455,8 +455,7 @@ static int init_vq(struct virtio_blk *vblk)
>  	}
> 
>  	/* Discover virtqueues and write information to configuration.  */
> -	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names,
> -			&desc);
> +	err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc);
>  	if (err)
>  		goto out;
> 
> diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
> index e9b7e0b..5da4c8e 100644
> --- a/drivers/char/virtio_console.c
> +++ b/drivers/char/virtio_console.c
> @@ -1945,9 +1945,9 @@ static int init_vqs(struct ports_device *portdev)
>  		}
>  	}
>  	/* Find the queues. */
> -	err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
> -					      io_callbacks,
> -					      (const char **)io_names, NULL);
> +	err = virtio_find_vqs(portdev->vdev, nr_queues, vqs,
> +			      io_callbacks,
> +			      (const char **)io_names, NULL);
>  	if (err)
>  		goto free;
> 
> diff --git a/drivers/crypto/virtio/virtio_crypto_core.c
> b/drivers/crypto/virtio/virtio_crypto_core.c
> index 21472e4..a111cd72 100644
> --- a/drivers/crypto/virtio/virtio_crypto_core.c
> +++ b/drivers/crypto/virtio/virtio_crypto_core.c
> @@ -119,8 +119,7 @@ static int virtcrypto_find_vqs(struct virtio_crypto *vi)
>  		names[i] = vi->data_vq[i].name;
>  	}
> 
> -	ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
> -					 names, NULL);
> +	ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
>  	if (ret)
>  		goto err_find;
> 
> diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c
> b/drivers/gpu/drm/virtio/virtgpu_kms.c
> index 4918668..1e1c90b 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_kms.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
> @@ -175,8 +175,7 @@ int virtio_gpu_driver_load(struct drm_device *dev,
> unsigned long flags)
>  	DRM_INFO("virgl 3d acceleration not supported by guest\n");
>  #endif
> 
> -	ret = vgdev->vdev->config->find_vqs(vgdev->vdev, 2, vqs,
> -					    callbacks, names, NULL);
> +	ret = virtio_find_vqs(vgdev->vdev, 2, vqs, callbacks, names, NULL);
>  	if (ret) {
>  		DRM_ERROR("failed to find virt queues\n");
>  		goto err_vqs;
> diff --git a/drivers/net/caif/caif_virtio.c b/drivers/net/caif/caif_virtio.c
> index bc0eb47..6122768 100644
> --- a/drivers/net/caif/caif_virtio.c
> +++ b/drivers/net/caif/caif_virtio.c
> @@ -679,8 +679,7 @@ static int cfv_probe(struct virtio_device *vdev)
>  		goto err;
> 
>  	/* Get the TX virtio ring. This is a "guest side vring". */
> -	err = vdev->config->find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs, &names,
> -			NULL);
> +	err = virtio_find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs, &names, NULL);
>  	if (err)
>  		goto err;
> 
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index ea9890d..6802169 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -2079,8 +2079,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
>  		names[txq2vq(i)] = vi->sq[i].name;
>  	}
> 
> -	ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
> -					 names, NULL);
> +	ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
>  	if (ret)
>  		goto err_find;
> 
> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c
> b/drivers/rpmsg/virtio_rpmsg_bus.c
> index 5e66e08..f7cade0 100644
> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> @@ -869,7 +869,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
>  	init_waitqueue_head(&vrp->sendq);
> 
>  	/* We expect two virtqueues, rx and tx (and in this order) */
> -	err = vdev->config->find_vqs(vdev, 2, vqs, vq_cbs, names, NULL);
> +	err = virtio_find_vqs(vdev, 2, vqs, vq_cbs, names, NULL);
>  	if (err)
>  		goto free_vrp;
> 
> diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
> index 939c47d..e9222dc 100644
> --- a/drivers/scsi/virtio_scsi.c
> +++ b/drivers/scsi/virtio_scsi.c
> @@ -870,8 +870,7 @@ static int virtscsi_init(struct virtio_device *vdev,
>  	}
> 
>  	/* Discover virtqueues and write information to configuration.  */
> -	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names,
> -			&desc);
> +	err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc);
>  	if (err)
>  		goto out;
> 
> diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
> index 34adf9b..408c174 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -418,8 +418,7 @@ static int init_vqs(struct virtio_balloon *vb)
>  	 * optionally stat.
>  	 */
>  	nvqs = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ) ? 3 :
> 2;
> -	err = vb->vdev->config->find_vqs(vb->vdev, nvqs, vqs, callbacks, names,
> -			NULL);
> +	err = virtio_find_vqs(vb->vdev, nvqs, vqs, callbacks, names, NULL);
>  	if (err)
>  		return err;
> 
> diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c
> index 79f1293..3a0468f 100644
> --- a/drivers/virtio/virtio_input.c
> +++ b/drivers/virtio/virtio_input.c
> @@ -173,8 +173,7 @@ static int virtinput_init_vqs(struct virtio_input *vi)
>  	static const char * const names[] = { "events", "status" };
>  	int err;
> 
> -	err = vi->vdev->config->find_vqs(vi->vdev, 2, vqs, cbs, names,
> -			NULL);
> +	err = virtio_find_vqs(vi->vdev, 2, vqs, cbs, names, NULL);
>  	if (err)
>  		return err;
>  	vi->evt = vqs[0];
> diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> index 8355bab..47f3d80 100644
> --- a/include/linux/virtio_config.h
> +++ b/include/linux/virtio_config.h
> @@ -179,6 +179,15 @@ struct virtqueue *virtio_find_single_vq(struct
> virtio_device *vdev,
>  	return vq;
>  }
> 
> +static inline
> +int virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> +			struct virtqueue *vqs[], vq_callback_t *callbacks[],
> +			const char * const names[],
> +			struct irq_affinity *desc)
> +{
> +	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, desc);
> +}
> +
>  /**
>   * virtio_device_ready - enable vq use in probe function
>   * @vdev: the device
> diff --git a/net/vmw_vsock/virtio_transport.c
> b/net/vmw_vsock/virtio_transport.c
> index 68675a1..97e26e2 100644
> --- a/net/vmw_vsock/virtio_transport.c
> +++ b/net/vmw_vsock/virtio_transport.c
> @@ -573,9 +573,9 @@ static int virtio_vsock_probe(struct virtio_device
> *vdev)
> 
>  	vsock->vdev = vdev;
> 
> -	ret = vsock->vdev->config->find_vqs(vsock->vdev, VSOCK_VQ_MAX,
> -					    vsock->vqs, callbacks, names,
> -					    NULL);
> +	ret = virtio_find_vqs(vsock->vdev, VSOCK_VQ_MAX,
> +			      vsock->vqs, callbacks, names,
> +			      NULL);
>  	if (ret < 0)
>  		goto out;
> 
> --
> MST

Re: [PATCH 1/6] virtio: wrap find_vqs

[Jason Wang]

On 2017年03月30日 04:48, Michael S. Tsirkin wrote:
> We are going to add more parameters to find_vqs, let's wrap the call so
> we don't need to tweak all drivers every time.
>
> Signed-off-by: Michael S. Tsirkin<mst@redhat.com>
> ---

A quick glance and it looks ok, but what the benefit of this series, is 
it required by other changes?

Thanks

Re: [PATCH 1/6] virtio: wrap find_vqs

[Michael S. Tsirkin]

On Thu, Mar 30, 2017 at 02:00:08PM +0800, Jason Wang wrote:
> 
> 
> On 2017年03月30日 04:48, Michael S. Tsirkin wrote:
> > We are going to add more parameters to find_vqs, let's wrap the call so
> > we don't need to tweak all drivers every time.
> > 
> > Signed-off-by: Michael S. Tsirkin<mst@redhat.com>
> > ---
> 
> A quick glance and it looks ok, but what the benefit of this series, is it
> required by other changes?
> 
> Thanks

Yes - to avoid touching all devices when doing the rest of
the patchset.
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Re: [PATCH 1/6] virtio: wrap find_vqs

[Jason Wang]

On 2017年03月30日 22:32, Michael S. Tsirkin wrote:
> On Thu, Mar 30, 2017 at 02:00:08PM +0800, Jason Wang wrote:
>>
>> On 2017年03月30日 04:48, Michael S. Tsirkin wrote:
>>> We are going to add more parameters to find_vqs, let's wrap the call so
>>> we don't need to tweak all drivers every time.
>>>
>>> Signed-off-by: Michael S. Tsirkin<mst@redhat.com>
>>> ---
>> A quick glance and it looks ok, but what the benefit of this series, is it
>> required by other changes?
>>
>> Thanks
> Yes - to avoid touching all devices when doing the rest of
> the patchset.

Maybe I'm not clear. I mean the benefit of this series not this single 
patch. I guess it may be used by you proposal that avoid reset when set 
XDP? If yes, do we really want to drop some packets after XDP is set?

Thanks

Re: [PATCH 1/6] virtio: wrap find_vqs

[Michael S. Tsirkin]

On Fri, Mar 31, 2017 at 12:04:55PM +0800, Jason Wang wrote:
> 
> 
> On 2017年03月30日 22:32, Michael S. Tsirkin wrote:
> > On Thu, Mar 30, 2017 at 02:00:08PM +0800, Jason Wang wrote:
> > > 
> > > On 2017年03月30日 04:48, Michael S. Tsirkin wrote:
> > > > We are going to add more parameters to find_vqs, let's wrap the call so
> > > > we don't need to tweak all drivers every time.
> > > > 
> > > > Signed-off-by: Michael S. Tsirkin<mst@redhat.com>
> > > > ---
> > > A quick glance and it looks ok, but what the benefit of this series, is it
> > > required by other changes?
> > > 
> > > Thanks
> > Yes - to avoid touching all devices when doing the rest of
> > the patchset.
> 
> Maybe I'm not clear. I mean the benefit of this series not this single
> patch. I guess it may be used by you proposal that avoid reset when set XDP?

In particular, yes. It generally simplifies things significantly if
we can get the true buffer size back.

> If yes, do we really want to drop some packets after XDP is set?
> 
> Thanks

We would rather not drop packets. We could detect and copy them to make
XDP work.

-- 
MST

Re: [PATCH 1/6] virtio: wrap find_vqs

[Cornelia Huck]

On Wed, 29 Mar 2017 23:48:44 +0300
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> We are going to add more parameters to find_vqs, let's wrap the call so
> we don't need to tweak all drivers every time.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>  drivers/block/virtio_blk.c                 | 3 +--
>  drivers/char/virtio_console.c              | 6 +++---
>  drivers/crypto/virtio/virtio_crypto_core.c | 3 +--
>  drivers/gpu/drm/virtio/virtgpu_kms.c       | 3 +--
>  drivers/net/caif/caif_virtio.c             | 3 +--
>  drivers/net/virtio_net.c                   | 3 +--
>  drivers/rpmsg/virtio_rpmsg_bus.c           | 2 +-
>  drivers/scsi/virtio_scsi.c                 | 3 +--
>  drivers/virtio/virtio_balloon.c            | 3 +--
>  drivers/virtio/virtio_input.c              | 3 +--
>  include/linux/virtio_config.h              | 9 +++++++++
>  net/vmw_vsock/virtio_transport.c           | 6 +++---
>  12 files changed, 24 insertions(+), 23 deletions(-)

Regardless whether that context thing is the right thing to do, this
looks like a sensible cleanup.

Re: [PATCH 1/6] virtio: wrap find_vqs

[Bjorn Andersson]

On Wed 29 Mar 13:48 PDT 2017, Michael S. Tsirkin wrote:

> We are going to add more parameters to find_vqs, let's wrap the call so
> we don't need to tweak all drivers every time.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

[PATCH 2/6] virtio: add context flag to find vqs

[Michael S. Tsirkin]

Allows maintaining extra context per vq.  For ease of use, passing in
NULL is legal and disables the feature for all vqs.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/misc/mic/vop/vop_main.c    |  9 ++++++---
 drivers/s390/virtio/kvm_virtio.c   |  6 ++++--
 drivers/s390/virtio/virtio_ccw.c   |  7 ++++---
 drivers/virtio/virtio_mmio.c       |  8 +++++---
 drivers/virtio/virtio_pci_common.c | 18 +++++++++++-------
 drivers/virtio/virtio_pci_common.h |  4 +++-
 drivers/virtio/virtio_pci_legacy.c |  4 +++-
 drivers/virtio/virtio_pci_modern.c | 12 ++++++++----
 drivers/virtio/virtio_ring.c       |  7 +++++--
 include/linux/virtio_config.h      | 18 +++++++++++++++---
 include/linux/virtio_ring.h        |  3 +++
 11 files changed, 67 insertions(+), 29 deletions(-)

diff --git a/drivers/misc/mic/vop/vop_main.c b/drivers/misc/mic/vop/vop_main.c
index c2e29d7..a341938 100644
--- a/drivers/misc/mic/vop/vop_main.c
+++ b/drivers/misc/mic/vop/vop_main.c
@@ -278,7 +278,7 @@ static void vop_del_vqs(struct virtio_device *dev)
 static struct virtqueue *vop_find_vq(struct virtio_device *dev,
 				     unsigned index,
 				     void (*callback)(struct virtqueue *vq),
-				     const char *name)
+				     const char *name, bool ctx)
 {
 	struct _vop_vdev *vdev = to_vopvdev(dev);
 	struct vop_device *vpdev = vdev->vpdev;
@@ -314,6 +314,7 @@ static struct virtqueue *vop_find_vq(struct virtio_device *dev,
 				le16_to_cpu(config.num), MIC_VIRTIO_RING_ALIGN,
 				dev,
 				false,
+				ctx,
 				(void __force *)va, vop_notify, callback, name);
 	if (!vq) {
 		err = -ENOMEM;
@@ -374,7 +375,8 @@ static struct virtqueue *vop_find_vq(struct virtio_device *dev,
 static int vop_find_vqs(struct virtio_device *dev, unsigned nvqs,
 			struct virtqueue *vqs[],
 			vq_callback_t *callbacks[],
-			const char * const names[], struct irq_affinity *desc)
+			const char * const names[], const bool *ctx,
+			struct irq_affinity *desc)
 {
 	struct _vop_vdev *vdev = to_vopvdev(dev);
 	struct vop_device *vpdev = vdev->vpdev;
@@ -388,7 +390,8 @@ static int vop_find_vqs(struct virtio_device *dev, unsigned nvqs,
 	for (i = 0; i < nvqs; ++i) {
 		dev_dbg(_vop_dev(vdev), "%s: %d: %s\n",
 			__func__, i, names[i]);
-		vqs[i] = vop_find_vq(dev, i, callbacks[i], names[i]);
+		vqs[i] = vop_find_vq(dev, i, callbacks[i], names[i],
+				     ctx ? ctx[i] : false);
 		if (IS_ERR(vqs[i])) {
 			err = PTR_ERR(vqs[i]);
 			goto error;
diff --git a/drivers/s390/virtio/kvm_virtio.c b/drivers/s390/virtio/kvm_virtio.c
index 2ce0b3e..81b33aa 100644
--- a/drivers/s390/virtio/kvm_virtio.c
+++ b/drivers/s390/virtio/kvm_virtio.c
@@ -189,7 +189,7 @@ static bool kvm_notify(struct virtqueue *vq)
 static struct virtqueue *kvm_find_vq(struct virtio_device *vdev,
 				     unsigned index,
 				     void (*callback)(struct virtqueue *vq),
-				     const char *name)
+				     const char *name, bool ctx)
 {
 	struct kvm_device *kdev = to_kvmdev(vdev);
 	struct kvm_vqconfig *config;
@@ -256,6 +256,7 @@ static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 			struct virtqueue *vqs[],
 			vq_callback_t *callbacks[],
 			const char * const names[],
+			const bool *ctx,
 			struct irq_affinity *desc)
 {
 	struct kvm_device *kdev = to_kvmdev(vdev);
@@ -266,7 +267,8 @@ static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		return -ENOENT;
 
 	for (i = 0; i < nvqs; ++i) {
-		vqs[i] = kvm_find_vq(vdev, i, callbacks[i], names[i]);
+		vqs[i] = kvm_find_vq(vdev, i, callbacks[i], names[i],
+				     ctx ? ctx[i] : false);
 		if (IS_ERR(vqs[i]))
 			goto error;
 	}
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index 0ed209f..2a76ea7 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -484,7 +484,7 @@ static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 
 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 					     int i, vq_callback_t *callback,
-					     const char *name,
+					     const char *name, bool ctx,
 					     struct ccw1 *ccw)
 {
 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
@@ -522,7 +522,7 @@ static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 	}
 
 	vq = vring_new_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, vdev,
-				 true, info->queue, virtio_ccw_kvm_notify,
+				 true, ctx, info->queue, virtio_ccw_kvm_notify,
 				 callback, name);
 	if (!vq) {
 		/* For now, we fail if we can't get the requested size. */
@@ -629,6 +629,7 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 			       struct virtqueue *vqs[],
 			       vq_callback_t *callbacks[],
 			       const char * const names[],
+			       const bool *ctx,
 			       struct irq_affinity *desc)
 {
 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
@@ -642,7 +643,7 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 
 	for (i = 0; i < nvqs; ++i) {
 		vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
-					     ccw);
+					     ctx ? ctx[i] : false, ccw);
 		if (IS_ERR(vqs[i])) {
 			ret = PTR_ERR(vqs[i]);
 			vqs[i] = NULL;
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 78343b8..74dc717 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -351,7 +351,7 @@ static void vm_del_vqs(struct virtio_device *vdev)
 
 static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index,
 				  void (*callback)(struct virtqueue *vq),
-				  const char *name)
+				  const char *name, bool ctx)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
 	struct virtio_mmio_vq_info *info;
@@ -388,7 +388,7 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index,
 
 	/* Create the vring */
 	vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, vdev,
-				 true, true, vm_notify, callback, name);
+				 true, true, ctx, vm_notify, callback, name);
 	if (!vq) {
 		err = -ENOMEM;
 		goto error_new_virtqueue;
@@ -447,6 +447,7 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		       struct virtqueue *vqs[],
 		       vq_callback_t *callbacks[],
 		       const char * const names[],
+		       const bool *ctx,
 		       struct irq_affinity *desc)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
@@ -459,7 +460,8 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		return err;
 
 	for (i = 0; i < nvqs; ++i) {
-		vqs[i] = vm_setup_vq(vdev, i, callbacks[i], names[i]);
+		vqs[i] = vm_setup_vq(vdev, i, callbacks[i], names[i],
+				     ctx ? ctx[i] : false);
 		if (IS_ERR(vqs[i])) {
 			vm_del_vqs(vdev);
 			return PTR_ERR(vqs[i]);
diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c
index 5905349..18e74c8 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -143,7 +143,8 @@ void vp_del_vqs(struct virtio_device *vdev)
 
 static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], struct irq_affinity *desc)
+		const char * const names[], const bool *ctx,
+		struct irq_affinity *desc)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	const char *name = dev_name(&vp_dev->vdev.dev);
@@ -225,7 +226,8 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
 			msix_vec = VIRTIO_MSI_NO_VECTOR;
 
 		vqs[i] = vp_dev->setup_vq(vp_dev, i, callbacks[i], names[i],
-				msix_vec);
+					  ctx ? ctx[i] : false,
+					  msix_vec);
 		if (IS_ERR(vqs[i])) {
 			err = PTR_ERR(vqs[i]);
 			goto out_remove_vqs;
@@ -282,7 +284,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
 
 static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[])
+		const char * const names[], const bool *ctx)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	int i, err;
@@ -298,7 +300,8 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned nvqs,
 			continue;
 		}
 		vqs[i] = vp_dev->setup_vq(vp_dev, i, callbacks[i], names[i],
-				VIRTIO_MSI_NO_VECTOR);
+					  ctx ? ctx[i] : false,
+					  VIRTIO_MSI_NO_VECTOR);
 		if (IS_ERR(vqs[i])) {
 			err = PTR_ERR(vqs[i]);
 			goto out_remove_vqs;
@@ -316,14 +319,15 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned nvqs,
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], struct irq_affinity *desc)
+		const char * const names[], const bool *ctx,
+		struct irq_affinity *desc)
 {
 	int err;
 
-	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, desc);
+	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, ctx, desc);
 	if (!err)
 		return 0;
-	return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names);
+	return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names, ctx);
 }
 
 const char *vp_bus_name(struct virtio_device *vdev)
diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h
index ac8c9d7..8149dd3 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -77,6 +77,7 @@ struct virtio_pci_device {
 				      unsigned idx,
 				      void (*callback)(struct virtqueue *vq),
 				      const char *name,
+				      bool ctx,
 				      u16 msix_vec);
 	void (*del_vq)(struct virtqueue *vq);
 
@@ -98,7 +99,8 @@ void vp_del_vqs(struct virtio_device *vdev);
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], struct irq_affinity *desc);
+		const char * const names[], const bool *ctx,
+		struct irq_affinity *desc);
 const char *vp_bus_name(struct virtio_device *vdev);
 
 /* Setup the affinity for a virtqueue:
diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c
index f7362c5..a976452 100644
--- a/drivers/virtio/virtio_pci_legacy.c
+++ b/drivers/virtio/virtio_pci_legacy.c
@@ -115,6 +115,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 				  unsigned index,
 				  void (*callback)(struct virtqueue *vq),
 				  const char *name,
+				  bool ctx,
 				  u16 msix_vec)
 {
 	struct virtqueue *vq;
@@ -132,7 +133,8 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 	/* create the vring */
 	vq = vring_create_virtqueue(index, num,
 				    VIRTIO_PCI_VRING_ALIGN, &vp_dev->vdev,
-				    true, false, vp_notify, callback, name);
+				    true, false, ctx,
+				    vp_notify, callback, name);
 	if (!vq)
 		return ERR_PTR(-ENOMEM);
 
diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index 7bc3004..709f7e2 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -296,6 +296,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 				  unsigned index,
 				  void (*callback)(struct virtqueue *vq),
 				  const char *name,
+				  bool ctx,
 				  u16 msix_vec)
 {
 	struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
@@ -325,7 +326,8 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 	/* create the vring */
 	vq = vring_create_virtqueue(index, num,
 				    SMP_CACHE_BYTES, &vp_dev->vdev,
-				    true, true, vp_notify, callback, name);
+				    true, true, ctx,
+				    vp_notify, callback, name);
 	if (!vq)
 		return ERR_PTR(-ENOMEM);
 
@@ -384,12 +386,14 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 }
 
 static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
-		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], struct irq_affinity *desc)
+			      struct virtqueue *vqs[],
+			      vq_callback_t *callbacks[],
+			      const char * const names[], const bool *ctx,
+			      struct irq_affinity *desc)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	struct virtqueue *vq;
-	int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, desc);
+	int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc);
 
 	if (rc)
 		return rc;
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 409aeaa..b23b5fa 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -916,6 +916,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
 					struct vring vring,
 					struct virtio_device *vdev,
 					bool weak_barriers,
+					bool context,
 					bool (*notify)(struct virtqueue *),
 					void (*callback)(struct virtqueue *),
 					const char *name)
@@ -1019,6 +1020,7 @@ struct virtqueue *vring_create_virtqueue(
 	struct virtio_device *vdev,
 	bool weak_barriers,
 	bool may_reduce_num,
+	bool context,
 	bool (*notify)(struct virtqueue *),
 	void (*callback)(struct virtqueue *),
 	const char *name)
@@ -1058,7 +1060,7 @@ struct virtqueue *vring_create_virtqueue(
 	queue_size_in_bytes = vring_size(num, vring_align);
 	vring_init(&vring, num, queue, vring_align);
 
-	vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers,
+	vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers, context,
 				   notify, callback, name);
 	if (!vq) {
 		vring_free_queue(vdev, queue_size_in_bytes, queue,
@@ -1079,6 +1081,7 @@ struct virtqueue *vring_new_virtqueue(unsigned int index,
 				      unsigned int vring_align,
 				      struct virtio_device *vdev,
 				      bool weak_barriers,
+				      bool context,
 				      void *pages,
 				      bool (*notify)(struct virtqueue *vq),
 				      void (*callback)(struct virtqueue *vq),
@@ -1086,7 +1089,7 @@ struct virtqueue *vring_new_virtqueue(unsigned int index,
 {
 	struct vring vring;
 	vring_init(&vring, num, pages, vring_align);
-	return __vring_new_virtqueue(index, vring, vdev, weak_barriers,
+	return __vring_new_virtqueue(index, vring, vdev, weak_barriers, context,
 				     notify, callback, name);
 }
 EXPORT_SYMBOL_GPL(vring_new_virtqueue);
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 47f3d80..0133d8a 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -72,7 +72,8 @@ struct virtio_config_ops {
 	void (*reset)(struct virtio_device *vdev);
 	int (*find_vqs)(struct virtio_device *, unsigned nvqs,
 			struct virtqueue *vqs[], vq_callback_t *callbacks[],
-			const char * const names[], struct irq_affinity *desc);
+			const char * const names[], const bool *ctx,
+			struct irq_affinity *desc);
 	void (*del_vqs)(struct virtio_device *);
 	u64 (*get_features)(struct virtio_device *vdev);
 	int (*finalize_features)(struct virtio_device *vdev);
@@ -173,7 +174,8 @@ struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev,
 	vq_callback_t *callbacks[] = { c };
 	const char *names[] = { n };
 	struct virtqueue *vq;
-	int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names, NULL);
+	int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names, NULL,
+					 NULL);
 	if (err < 0)
 		return ERR_PTR(err);
 	return vq;
@@ -185,7 +187,17 @@ int virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 			const char * const names[],
 			struct irq_affinity *desc)
 {
-	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, desc);
+	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL, desc);
+}
+
+static inline
+int virtio_find_vqs_ctx(struct virtio_device *vdev, unsigned nvqs,
+			struct virtqueue *vqs[], vq_callback_t *callbacks[],
+			const char * const names[], const bool *ctx,
+			struct irq_affinity *desc)
+{
+	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, ctx,
+				      desc);
 }
 
 /**
diff --git a/include/linux/virtio_ring.h b/include/linux/virtio_ring.h
index e8d3693..270cfa8 100644
--- a/include/linux/virtio_ring.h
+++ b/include/linux/virtio_ring.h
@@ -71,6 +71,7 @@ struct virtqueue *vring_create_virtqueue(unsigned int index,
 					 struct virtio_device *vdev,
 					 bool weak_barriers,
 					 bool may_reduce_num,
+					 bool ctx,
 					 bool (*notify)(struct virtqueue *vq),
 					 void (*callback)(struct virtqueue *vq),
 					 const char *name);
@@ -80,6 +81,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
 					struct vring vring,
 					struct virtio_device *vdev,
 					bool weak_barriers,
+					bool ctx,
 					bool (*notify)(struct virtqueue *),
 					void (*callback)(struct virtqueue *),
 					const char *name);
@@ -93,6 +95,7 @@ struct virtqueue *vring_new_virtqueue(unsigned int index,
 				      unsigned int vring_align,
 				      struct virtio_device *vdev,
 				      bool weak_barriers,
+				      bool ctx,
 				      void *pages,
 				      bool (*notify)(struct virtqueue *vq),
 				      void (*callback)(struct virtqueue *vq),
-- 
MST

Re: [PATCH 2/6] virtio: add context flag to find vqs

[Cornelia Huck]

On Wed, 29 Mar 2017 23:48:51 +0300
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> Allows maintaining extra context per vq.  For ease of use, passing in
> NULL is legal and disables the feature for all vqs.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>  drivers/misc/mic/vop/vop_main.c    |  9 ++++++---
>  drivers/s390/virtio/kvm_virtio.c   |  6 ++++--
>  drivers/s390/virtio/virtio_ccw.c   |  7 ++++---
>  drivers/virtio/virtio_mmio.c       |  8 +++++---
>  drivers/virtio/virtio_pci_common.c | 18 +++++++++++-------
>  drivers/virtio/virtio_pci_common.h |  4 +++-
>  drivers/virtio/virtio_pci_legacy.c |  4 +++-
>  drivers/virtio/virtio_pci_modern.c | 12 ++++++++----
>  drivers/virtio/virtio_ring.c       |  7 +++++--
>  include/linux/virtio_config.h      | 18 +++++++++++++++---
>  include/linux/virtio_ring.h        |  3 +++
>  11 files changed, 67 insertions(+), 29 deletions(-)

This series really needs a cover letter, explaining the motivation for
adding this context.

>From what I understand, you want to track some length parameter in
virtio-net. As you don't use indirect descriptors in that case, you
want to use a context instead. Did I get this correctly?

Re: [PATCH 2/6] virtio: add context flag to find vqs

[Michael S. Tsirkin]

On Thu, Mar 30, 2017 at 09:17:31AM +0200, Cornelia Huck wrote:
> On Wed, 29 Mar 2017 23:48:51 +0300
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
> 
> > Allows maintaining extra context per vq.  For ease of use, passing in
> > NULL is legal and disables the feature for all vqs.
> > 
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> >  drivers/misc/mic/vop/vop_main.c    |  9 ++++++---
> >  drivers/s390/virtio/kvm_virtio.c   |  6 ++++--
> >  drivers/s390/virtio/virtio_ccw.c   |  7 ++++---
> >  drivers/virtio/virtio_mmio.c       |  8 +++++---
> >  drivers/virtio/virtio_pci_common.c | 18 +++++++++++-------
> >  drivers/virtio/virtio_pci_common.h |  4 +++-
> >  drivers/virtio/virtio_pci_legacy.c |  4 +++-
> >  drivers/virtio/virtio_pci_modern.c | 12 ++++++++----
> >  drivers/virtio/virtio_ring.c       |  7 +++++--
> >  include/linux/virtio_config.h      | 18 +++++++++++++++---
> >  include/linux/virtio_ring.h        |  3 +++
> >  11 files changed, 67 insertions(+), 29 deletions(-)
> 
> This series really needs a cover letter, explaining the motivation for
> adding this context.

True. Will try to improve that for v2.

> From what I understand, you want to track some length parameter in
> virtio-net. As you don't use indirect descriptors in that case, you
> want to use a context instead. Did I get this correctly?

Exactly.

-- 
MST