virtio: Add get_shm_region method

Virtio defines 'shared memory regions' that provide a continuously
shared region between the host and guest.

Provide a method to find a particular region on a device.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
Sebastien Boeuf 2020-08-19 18:19:41 -04:00 коммит произвёл Miklos Szeredi
Родитель 9123e3a74e
Коммит 5bfe37ca8a
1 изменённых файлов: 17 добавлений и 0 удалений

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@ -11,6 +11,11 @@
struct irq_affinity;
struct virtio_shm_region {
u64 addr;
u64 len;
};
/**
* virtio_config_ops - operations for configuring a virtio device
* Note: Do not assume that a transport implements all of the operations
@ -66,6 +71,7 @@ struct irq_affinity;
* the caller can then copy.
* @set_vq_affinity: set the affinity for a virtqueue (optional).
* @get_vq_affinity: get the affinity for a virtqueue (optional).
* @get_shm_region: get a shared memory region based on the index.
*/
typedef void vq_callback_t(struct virtqueue *);
struct virtio_config_ops {
@ -89,6 +95,8 @@ struct virtio_config_ops {
const struct cpumask *cpu_mask);
const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev,
int index);
bool (*get_shm_region)(struct virtio_device *vdev,
struct virtio_shm_region *region, u8 id);
};
/* If driver didn't advertise the feature, it will never appear. */
@ -251,6 +259,15 @@ int virtqueue_set_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask)
return 0;
}
static inline
bool virtio_get_shm_region(struct virtio_device *vdev,
struct virtio_shm_region *region, u8 id)
{
if (!vdev->config->get_shm_region)
return false;
return vdev->config->get_shm_region(vdev, region, id);
}
static inline bool virtio_is_little_endian(struct virtio_device *vdev)
{
return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||