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Michael S. Tsirkin

2020-Jun-24 23:21 UTC

[PATCH v2 0/2] virtio: modernize DMA quirks

Use generic names for the quirks to make it clear it is not just about
the IOMMU, it's about DMA access in general.

changes from v1:
	added patch 2

Michael S. Tsirkin (2):
  virtio: VIRTIO_F_IOMMU_PLATFORM -> VIRTIO_F_ACCESS_PLATFORM
  virtio: virtio_has_iommu_quirk -> virtio_has_dma_quirk

 arch/um/drivers/virtio_uml.c            |  2 +-
 drivers/gpu/drm/virtio/virtgpu_object.c |  2 +-
 drivers/gpu/drm/virtio/virtgpu_vq.c     |  4 ++--
 drivers/vdpa/ifcvf/ifcvf_base.h         |  2 +-
 drivers/vdpa/vdpa_sim/vdpa_sim.c        |  4 ++--
 drivers/vhost/net.c                     |  4 ++--
 drivers/vhost/vdpa.c                    |  2 +-
 drivers/virtio/virtio_balloon.c         |  2 +-
 drivers/virtio/virtio_ring.c            |  4 ++--
 include/linux/virtio_config.h           |  6 +++---
 include/uapi/linux/virtio_config.h      | 10 +++++++---
 tools/virtio/linux/virtio_config.h      |  6 +++---
 12 files changed, 26 insertions(+), 22 deletions(-)

-- 
MST

Michael S. Tsirkin

2020-Jun-24 23:21 UTC

head link

[PATCH v2 1/2] virtio: VIRTIO_F_IOMMU_PLATFORM -> VIRTIO_F_ACCESS_PLATFORM

Rename the bit to match latest virtio spec.
Add a compat macro to avoid breaking existing userspace.

Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
 arch/um/drivers/virtio_uml.c       |  2 +-
 drivers/vdpa/ifcvf/ifcvf_base.h    |  2 +-
 drivers/vdpa/vdpa_sim/vdpa_sim.c   |  4 ++--
 drivers/vhost/net.c                |  4 ++--
 drivers/vhost/vdpa.c               |  2 +-
 drivers/virtio/virtio_balloon.c    |  2 +-
 drivers/virtio/virtio_ring.c       |  2 +-
 include/linux/virtio_config.h      |  2 +-
 include/uapi/linux/virtio_config.h | 10 +++++++---
 tools/virtio/linux/virtio_config.h |  2 +-
 10 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c
index 351aee52aca6..a6c4bb6c2c01 100644
--- a/arch/um/drivers/virtio_uml.c
+++ b/arch/um/drivers/virtio_uml.c
@@ -385,7 +385,7 @@ static irqreturn_t vu_req_interrupt(int irq, void *data)
 		}
 		break;
 	case VHOST_USER_SLAVE_IOTLB_MSG:
-		/* not supported - VIRTIO_F_IOMMU_PLATFORM */
+		/* not supported - VIRTIO_F_ACCESS_PLATFORM */
 	case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG:
 		/* not supported - VHOST_USER_PROTOCOL_F_HOST_NOTIFIER */
 	default:
diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h
index f4554412e607..24af422b5a3e 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.h
+++ b/drivers/vdpa/ifcvf/ifcvf_base.h
@@ -29,7 +29,7 @@
 		 (1ULL << VIRTIO_F_VERSION_1)			| \
 		 (1ULL << VIRTIO_NET_F_STATUS)			| \
 		 (1ULL << VIRTIO_F_ORDER_PLATFORM)		| \
-		 (1ULL << VIRTIO_F_IOMMU_PLATFORM)		| \
+		 (1ULL << VIRTIO_F_ACCESS_PLATFORM)		| \
 		 (1ULL << VIRTIO_NET_F_MRG_RXBUF))
 
 /* Only one queue pair for now. */
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index c7334cc65bb2..a9bc5e0fb353 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -55,7 +55,7 @@ struct vdpasim_virtqueue {
 
 static u64 vdpasim_features = (1ULL << VIRTIO_F_ANY_LAYOUT) |
 			      (1ULL << VIRTIO_F_VERSION_1)  |
-			      (1ULL << VIRTIO_F_IOMMU_PLATFORM);
+			      (1ULL << VIRTIO_F_ACCESS_PLATFORM);
 
 /* State of each vdpasim device */
 struct vdpasim {
@@ -450,7 +450,7 @@ static int vdpasim_set_features(struct vdpa_device *vdpa,
u64 features)
 	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
 
 	/* DMA mapping must be done by driver */
-	if (!(features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)))
+	if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))
 		return -EINVAL;
 
 	vdpasim->features = features & vdpasim_features;
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index e992decfec53..8e0921d3805d 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -73,7 +73,7 @@ enum {
 	VHOST_NET_FEATURES = VHOST_FEATURES |
 			 (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) |
 			 (1ULL << VIRTIO_NET_F_MRG_RXBUF) |
-			 (1ULL << VIRTIO_F_IOMMU_PLATFORM)
+			 (1ULL << VIRTIO_F_ACCESS_PLATFORM)
 };
 
 enum {
@@ -1653,7 +1653,7 @@ static int vhost_net_set_features(struct vhost_net *n, u64
features)
 	    !vhost_log_access_ok(&n->dev))
 		goto out_unlock;
 
-	if ((features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))) {
+	if ((features & (1ULL << VIRTIO_F_ACCESS_PLATFORM))) {
 		if (vhost_init_device_iotlb(&n->dev, true))
 			goto out_unlock;
 	}
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index a54b60d6623f..18869a35d408 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -31,7 +31,7 @@ enum {
 		(1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
 		(1ULL << VIRTIO_F_ANY_LAYOUT) |
 		(1ULL << VIRTIO_F_VERSION_1) |
-		(1ULL << VIRTIO_F_IOMMU_PLATFORM) |
+		(1ULL << VIRTIO_F_ACCESS_PLATFORM) |
 		(1ULL << VIRTIO_F_RING_PACKED) |
 		(1ULL << VIRTIO_F_ORDER_PLATFORM) |
 		(1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 1f157d2f4952..fc7301406540 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -1120,7 +1120,7 @@ static int virtballoon_validate(struct virtio_device
*vdev)
 	else if (!virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON))
 		__virtio_clear_bit(vdev, VIRTIO_BALLOON_F_REPORTING);
 
-	__virtio_clear_bit(vdev, VIRTIO_F_IOMMU_PLATFORM);
+	__virtio_clear_bit(vdev, VIRTIO_F_ACCESS_PLATFORM);
 	return 0;
 }
 
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 58b96baa8d48..a1a5c2a91426 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -2225,7 +2225,7 @@ void vring_transport_features(struct virtio_device *vdev)
 			break;
 		case VIRTIO_F_VERSION_1:
 			break;
-		case VIRTIO_F_IOMMU_PLATFORM:
+		case VIRTIO_F_ACCESS_PLATFORM:
 			break;
 		case VIRTIO_F_RING_PACKED:
 			break;
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index bb4cc4910750..f2cc2a0df174 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -171,7 +171,7 @@ static inline bool virtio_has_iommu_quirk(const struct
virtio_device *vdev)
 	 * Note the reverse polarity of the quirk feature (compared to most
 	 * other features), this is for compatibility with legacy systems.
 	 */
-	return !virtio_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
+	return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
 }
 
 static inline
diff --git a/include/uapi/linux/virtio_config.h
b/include/uapi/linux/virtio_config.h
index ff8e7dc9d4dd..b5eda06f0d57 100644
--- a/include/uapi/linux/virtio_config.h
+++ b/include/uapi/linux/virtio_config.h
@@ -67,13 +67,17 @@
 #define VIRTIO_F_VERSION_1		32
 
 /*
- * If clear - device has the IOMMU bypass quirk feature.
- * If set - use platform tools to detect the IOMMU.
+ * If clear - device has the platform DMA (e.g. IOMMU) bypass quirk feature.
+ * If set - use platform DMA tools to access the memory.
  *
  * Note the reverse polarity (compared to most other features),
  * this is for compatibility with legacy systems.
  */
-#define VIRTIO_F_IOMMU_PLATFORM		33
+#define VIRTIO_F_ACCESS_PLATFORM	33
+#ifndef __KERNEL__
+/* Legacy name for VIRTIO_F_ACCESS_PLATFORM (for compatibility with old
userspace) */
+#define VIRTIO_F_IOMMU_PLATFORM		VIRTIO_F_ACCESS_PLATFORM
+#endif /* __KERNEL__ */
 
 /* This feature indicates support for the packed virtqueue layout. */
 #define VIRTIO_F_RING_PACKED		34
diff --git a/tools/virtio/linux/virtio_config.h
b/tools/virtio/linux/virtio_config.h
index dbf14c1e2188..f99ae42668e0 100644
--- a/tools/virtio/linux/virtio_config.h
+++ b/tools/virtio/linux/virtio_config.h
@@ -51,7 +51,7 @@ static inline bool virtio_has_iommu_quirk(const struct
virtio_device *vdev)
 	 * Note the reverse polarity of the quirk feature (compared to most
 	 * other features), this is for compatibility with legacy systems.
 	 */
-	return !virtio_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
+	return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
 }
 
 static inline bool virtio_is_little_endian(struct virtio_device *vdev)
-- 
MST

Michael S. Tsirkin

2020-Jun-24 23:21 UTC

head link

[PATCH v2 2/2] virtio: virtio_has_iommu_quirk -> virtio_has_dma_quirk

Now that the corresponding feature bit has been renamed,
rename the quirk too - it's about special ways to
do DMA, not necessarily about the IOMMU.

Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
 drivers/gpu/drm/virtio/virtgpu_object.c | 2 +-
 drivers/gpu/drm/virtio/virtgpu_vq.c     | 4 ++--
 drivers/virtio/virtio_ring.c            | 2 +-
 include/linux/virtio_config.h           | 4 ++--
 tools/virtio/linux/virtio_config.h      | 4 ++--
 5 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c
b/drivers/gpu/drm/virtio/virtgpu_object.c
index 6ccbd01cd888..e8799ab0c753 100644
--- a/drivers/gpu/drm/virtio/virtgpu_object.c
+++ b/drivers/gpu/drm/virtio/virtgpu_object.c
@@ -141,7 +141,7 @@ static int virtio_gpu_object_shmem_init(struct
virtio_gpu_device *vgdev,
 					struct virtio_gpu_mem_entry **ents,
 					unsigned int *nents)
 {
-	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
+	bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
 	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
 	struct scatterlist *sg;
 	int si, ret;
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c
b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 9e663a5d9952..53af60d484a4 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -599,7 +599,7 @@ void virtio_gpu_cmd_transfer_to_host_2d(struct
virtio_gpu_device *vgdev,
 	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(objs->objs[0]);
 	struct virtio_gpu_transfer_to_host_2d *cmd_p;
 	struct virtio_gpu_vbuffer *vbuf;
-	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
+	bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
 	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
 
 	if (use_dma_api)
@@ -1015,7 +1015,7 @@ void virtio_gpu_cmd_transfer_to_host_3d(struct
virtio_gpu_device *vgdev,
 	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(objs->objs[0]);
 	struct virtio_gpu_transfer_host_3d *cmd_p;
 	struct virtio_gpu_vbuffer *vbuf;
-	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
+	bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
 	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
 
 	if (use_dma_api)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index a1a5c2a91426..34253cb69cb8 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -240,7 +240,7 @@ static inline bool virtqueue_use_indirect(struct virtqueue
*_vq,
 
 static bool vring_use_dma_api(struct virtio_device *vdev)
 {
-	if (!virtio_has_iommu_quirk(vdev))
+	if (!virtio_has_dma_quirk(vdev))
 		return true;
 
 	/* Otherwise, we are left to guess. */
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index f2cc2a0df174..3b4eae5ac5e3 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -162,10 +162,10 @@ static inline bool virtio_has_feature(const struct
virtio_device *vdev,
 }
 
 /**
- * virtio_has_iommu_quirk - determine whether this device has the iommu quirk
+ * virtio_has_dma_quirk - determine whether this device has the DMA quirk
  * @vdev: the device
  */
-static inline bool virtio_has_iommu_quirk(const struct virtio_device *vdev)
+static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
 {
 	/*
 	 * Note the reverse polarity of the quirk feature (compared to most
diff --git a/tools/virtio/linux/virtio_config.h
b/tools/virtio/linux/virtio_config.h
index f99ae42668e0..f2640e505c4e 100644
--- a/tools/virtio/linux/virtio_config.h
+++ b/tools/virtio/linux/virtio_config.h
@@ -42,10 +42,10 @@ static inline void __virtio_clear_bit(struct virtio_device
*vdev,
 	(__virtio_test_bit((dev), feature))
 
 /**
- * virtio_has_iommu_quirk - determine whether this device has the iommu quirk
+ * virtio_has_dma_quirk - determine whether this device has the DMA quirk
  * @vdev: the device
  */
-static inline bool virtio_has_iommu_quirk(const struct virtio_device *vdev)
+static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
 {
 	/*
 	 * Note the reverse polarity of the quirk feature (compared to most
-- 
MST

David Hildenbrand

2020-Jun-25 06:50 UTC

head link

[PATCH v2 1/2] virtio: VIRTIO_F_IOMMU_PLATFORM -> VIRTIO_F_ACCESS_PLATFORM

On 25.06.20 01:21, Michael S. Tsirkin wrote:> Rename the bit to match latest virtio spec.
> Add a compat macro to avoid breaking existing userspace.
> 
> Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
> ---
>  arch/um/drivers/virtio_uml.c       |  2 +-
>  drivers/vdpa/ifcvf/ifcvf_base.h    |  2 +-
>  drivers/vdpa/vdpa_sim/vdpa_sim.c   |  4 ++--
>  drivers/vhost/net.c                |  4 ++--
>  drivers/vhost/vdpa.c               |  2 +-
>  drivers/virtio/virtio_balloon.c    |  2 +-
>  drivers/virtio/virtio_ring.c       |  2 +-
>  include/linux/virtio_config.h      |  2 +-
>  include/uapi/linux/virtio_config.h | 10 +++++++---
>  tools/virtio/linux/virtio_config.h |  2 +-
>  10 files changed, 18 insertions(+), 14 deletions(-)
> 
> diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c
> index 351aee52aca6..a6c4bb6c2c01 100644
> --- a/arch/um/drivers/virtio_uml.c
> +++ b/arch/um/drivers/virtio_uml.c
> @@ -385,7 +385,7 @@ static irqreturn_t vu_req_interrupt(int irq, void
*data)
>  		}
>  		break;
>  	case VHOST_USER_SLAVE_IOTLB_MSG:
> -		/* not supported - VIRTIO_F_IOMMU_PLATFORM */
> +		/* not supported - VIRTIO_F_ACCESS_PLATFORM */
>  	case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG:
>  		/* not supported - VHOST_USER_PROTOCOL_F_HOST_NOTIFIER */
>  	default:
> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h
b/drivers/vdpa/ifcvf/ifcvf_base.h
> index f4554412e607..24af422b5a3e 100644
> --- a/drivers/vdpa/ifcvf/ifcvf_base.h
> +++ b/drivers/vdpa/ifcvf/ifcvf_base.h
> @@ -29,7 +29,7 @@
>  		 (1ULL << VIRTIO_F_VERSION_1)			| \
>  		 (1ULL << VIRTIO_NET_F_STATUS)			| \
>  		 (1ULL << VIRTIO_F_ORDER_PLATFORM)		| \
> -		 (1ULL << VIRTIO_F_IOMMU_PLATFORM)		| \
> +		 (1ULL << VIRTIO_F_ACCESS_PLATFORM)		| \
>  		 (1ULL << VIRTIO_NET_F_MRG_RXBUF))
>  
>  /* Only one queue pair for now. */
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c
b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> index c7334cc65bb2..a9bc5e0fb353 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> @@ -55,7 +55,7 @@ struct vdpasim_virtqueue {
>  
>  static u64 vdpasim_features = (1ULL << VIRTIO_F_ANY_LAYOUT) |
>  			      (1ULL << VIRTIO_F_VERSION_1)  |
> -			      (1ULL << VIRTIO_F_IOMMU_PLATFORM);
> +			      (1ULL << VIRTIO_F_ACCESS_PLATFORM);
>  
>  /* State of each vdpasim device */
>  struct vdpasim {
> @@ -450,7 +450,7 @@ static int vdpasim_set_features(struct vdpa_device
*vdpa, u64 features)
>  	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
>  
>  	/* DMA mapping must be done by driver */
> -	if (!(features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)))
> +	if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))
>  		return -EINVAL;
>  
>  	vdpasim->features = features & vdpasim_features;
> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
> index e992decfec53..8e0921d3805d 100644
> --- a/drivers/vhost/net.c
> +++ b/drivers/vhost/net.c
> @@ -73,7 +73,7 @@ enum {
>  	VHOST_NET_FEATURES = VHOST_FEATURES |
>  			 (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) |
>  			 (1ULL << VIRTIO_NET_F_MRG_RXBUF) |
> -			 (1ULL << VIRTIO_F_IOMMU_PLATFORM)
> +			 (1ULL << VIRTIO_F_ACCESS_PLATFORM)
>  };
>  
>  enum {
> @@ -1653,7 +1653,7 @@ static int vhost_net_set_features(struct vhost_net
*n, u64 features)
>  	    !vhost_log_access_ok(&n->dev))
>  		goto out_unlock;
>  
> -	if ((features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))) {
> +	if ((features & (1ULL << VIRTIO_F_ACCESS_PLATFORM))) {
>  		if (vhost_init_device_iotlb(&n->dev, true))
>  			goto out_unlock;
>  	}
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index a54b60d6623f..18869a35d408 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -31,7 +31,7 @@ enum {
>  		(1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
>  		(1ULL << VIRTIO_F_ANY_LAYOUT) |
>  		(1ULL << VIRTIO_F_VERSION_1) |
> -		(1ULL << VIRTIO_F_IOMMU_PLATFORM) |
> +		(1ULL << VIRTIO_F_ACCESS_PLATFORM) |
>  		(1ULL << VIRTIO_F_RING_PACKED) |
>  		(1ULL << VIRTIO_F_ORDER_PLATFORM) |
>  		(1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
> diff --git a/drivers/virtio/virtio_balloon.c
b/drivers/virtio/virtio_balloon.c
> index 1f157d2f4952..fc7301406540 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -1120,7 +1120,7 @@ static int virtballoon_validate(struct virtio_device
*vdev)
>  	else if (!virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON))
>  		__virtio_clear_bit(vdev, VIRTIO_BALLOON_F_REPORTING);
>  
> -	__virtio_clear_bit(vdev, VIRTIO_F_IOMMU_PLATFORM);
> +	__virtio_clear_bit(vdev, VIRTIO_F_ACCESS_PLATFORM);
>  	return 0;
>  }
>  
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 58b96baa8d48..a1a5c2a91426 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -2225,7 +2225,7 @@ void vring_transport_features(struct virtio_device
*vdev)
>  			break;
>  		case VIRTIO_F_VERSION_1:
>  			break;
> -		case VIRTIO_F_IOMMU_PLATFORM:
> +		case VIRTIO_F_ACCESS_PLATFORM:
>  			break;
>  		case VIRTIO_F_RING_PACKED:
>  			break;
> diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> index bb4cc4910750..f2cc2a0df174 100644
> --- a/include/linux/virtio_config.h
> +++ b/include/linux/virtio_config.h
> @@ -171,7 +171,7 @@ static inline bool virtio_has_iommu_quirk(const struct
virtio_device *vdev)
>  	 * Note the reverse polarity of the quirk feature (compared to most
>  	 * other features), this is for compatibility with legacy systems.
>  	 */
> -	return !virtio_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
> +	return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
>  }
>  
>  static inline
> diff --git a/include/uapi/linux/virtio_config.h
b/include/uapi/linux/virtio_config.h
> index ff8e7dc9d4dd..b5eda06f0d57 100644
> --- a/include/uapi/linux/virtio_config.h
> +++ b/include/uapi/linux/virtio_config.h
> @@ -67,13 +67,17 @@
>  #define VIRTIO_F_VERSION_1		32
>  
>  /*
> - * If clear - device has the IOMMU bypass quirk feature.
> - * If set - use platform tools to detect the IOMMU.
> + * If clear - device has the platform DMA (e.g. IOMMU) bypass quirk
feature.
> + * If set - use platform DMA tools to access the memory.
>   *
>   * Note the reverse polarity (compared to most other features),
>   * this is for compatibility with legacy systems.
>   */
> -#define VIRTIO_F_IOMMU_PLATFORM		33
> +#define VIRTIO_F_ACCESS_PLATFORM	33
> +#ifndef __KERNEL__
> +/* Legacy name for VIRTIO_F_ACCESS_PLATFORM (for compatibility with old
userspace) */
> +#define VIRTIO_F_IOMMU_PLATFORM		VIRTIO_F_ACCESS_PLATFORM
> +#endif /* __KERNEL__ */
>  
>  /* This feature indicates support for the packed virtqueue layout. */
>  #define VIRTIO_F_RING_PACKED		34
> diff --git a/tools/virtio/linux/virtio_config.h
b/tools/virtio/linux/virtio_config.h
> index dbf14c1e2188..f99ae42668e0 100644
> --- a/tools/virtio/linux/virtio_config.h
> +++ b/tools/virtio/linux/virtio_config.h
> @@ -51,7 +51,7 @@ static inline bool virtio_has_iommu_quirk(const struct
virtio_device *vdev)
>  	 * Note the reverse polarity of the quirk feature (compared to most
>  	 * other features), this is for compatibility with legacy systems.
>  	 */
> -	return !virtio_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
> +	return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
>  }
>  
>  static inline bool virtio_is_little_endian(struct virtio_device *vdev)
> 
Reviewed-by: David Hildenbrand <david at redhat.com>

-- 
Thanks,

David / dhildenb

Jason Wang

2020-Jun-28 06:21 UTC

head link

[PATCH v2 2/2] virtio: virtio_has_iommu_quirk -> virtio_has_dma_quirk

On 2020/6/25 ??7:21, Michael S. Tsirkin wrote:> Now that the corresponding feature bit has been renamed,
> rename the quirk too - it's about special ways to
> do DMA, not necessarily about the IOMMU.
>
> Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
> ---
>   drivers/gpu/drm/virtio/virtgpu_object.c | 2 +-
>   drivers/gpu/drm/virtio/virtgpu_vq.c     | 4 ++--
>   drivers/virtio/virtio_ring.c            | 2 +-
>   include/linux/virtio_config.h           | 4 ++--
>   tools/virtio/linux/virtio_config.h      | 4 ++--
>   5 files changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c
b/drivers/gpu/drm/virtio/virtgpu_object.c
> index 6ccbd01cd888..e8799ab0c753 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_object.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_object.c
> @@ -141,7 +141,7 @@ static int virtio_gpu_object_shmem_init(struct
virtio_gpu_device *vgdev,
>   					struct virtio_gpu_mem_entry **ents,
>   					unsigned int *nents)
>   {
> -	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
> +	bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
>   	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
>   	struct scatterlist *sg;
>   	int si, ret;
> diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c
b/drivers/gpu/drm/virtio/virtgpu_vq.c
> index 9e663a5d9952..53af60d484a4 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_vq.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
> @@ -599,7 +599,7 @@ void virtio_gpu_cmd_transfer_to_host_2d(struct
virtio_gpu_device *vgdev,
>   	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(objs->objs[0]);
>   	struct virtio_gpu_transfer_to_host_2d *cmd_p;
>   	struct virtio_gpu_vbuffer *vbuf;
> -	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
> +	bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
>   	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
>   
>   	if (use_dma_api)
> @@ -1015,7 +1015,7 @@ void virtio_gpu_cmd_transfer_to_host_3d(struct
virtio_gpu_device *vgdev,
>   	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(objs->objs[0]);
>   	struct virtio_gpu_transfer_host_3d *cmd_p;
>   	struct virtio_gpu_vbuffer *vbuf;
> -	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
> +	bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
>   	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
>   
>   	if (use_dma_api)
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index a1a5c2a91426..34253cb69cb8 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -240,7 +240,7 @@ static inline bool virtqueue_use_indirect(struct
virtqueue *_vq,
>   
>   static bool vring_use_dma_api(struct virtio_device *vdev)
>   {
> -	if (!virtio_has_iommu_quirk(vdev))
> +	if (!virtio_has_dma_quirk(vdev))
>   		return true;
>   
>   	/* Otherwise, we are left to guess. */
> diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> index f2cc2a0df174..3b4eae5ac5e3 100644
> --- a/include/linux/virtio_config.h
> +++ b/include/linux/virtio_config.h
> @@ -162,10 +162,10 @@ static inline bool virtio_has_feature(const struct
virtio_device *vdev,
>   }
>   
>   /**
> - * virtio_has_iommu_quirk - determine whether this device has the iommu
quirk
> + * virtio_has_dma_quirk - determine whether this device has the DMA quirk
>    * @vdev: the device
>    */
> -static inline bool virtio_has_iommu_quirk(const struct virtio_device
*vdev)
> +static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
>   {
>   	/*
>   	 * Note the reverse polarity of the quirk feature (compared to most
> diff --git a/tools/virtio/linux/virtio_config.h
b/tools/virtio/linux/virtio_config.h
> index f99ae42668e0..f2640e505c4e 100644
> --- a/tools/virtio/linux/virtio_config.h
> +++ b/tools/virtio/linux/virtio_config.h
> @@ -42,10 +42,10 @@ static inline void __virtio_clear_bit(struct
virtio_device *vdev,
>   	(__virtio_test_bit((dev), feature))
>   
>   /**
> - * virtio_has_iommu_quirk - determine whether this device has the iommu
quirk
> + * virtio_has_dma_quirk - determine whether this device has the DMA quirk
>    * @vdev: the device
>    */
> -static inline bool virtio_has_iommu_quirk(const struct virtio_device
*vdev)
> +static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
>   {
>   	/*
>   	 * Note the reverse polarity of the quirk feature (compared to most

Acked-by: Jason Wang <jasowang at redhat.com>

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[PATCH v2 0/2] virtio: modernize DMA quirks

[PATCH v2 1/2] virtio: VIRTIO_F_IOMMU_PLATFORM -> VIRTIO_F_ACCESS_PLATFORM

[PATCH v2 2/2] virtio: virtio_has_iommu_quirk -> virtio_has_dma_quirk

[PATCH v2 1/2] virtio: VIRTIO_F_IOMMU_PLATFORM -> VIRTIO_F_ACCESS_PLATFORM

[PATCH v2 2/2] virtio: virtio_has_iommu_quirk -> virtio_has_dma_quirk

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