Re: [RFC v3 13/29] vhost: Add vhost_get_iova_range operation

[Jason Wang <jasowang@redhat.com>]

在 2021/5/27 上午1:49, Eugenio Perez Martin 写道:
> On Wed, May 26, 2021 at 3:14 AM Jason Wang <jasowang@redhat.com> wrote:
>>
>> 在 2021/5/20 上午12:28, Eugenio Pérez 写道:
>>> For simplicity, If a device does not support this operation it means
>>> that it can handle full (uint64_t)-1 iova address.
>>
>> Note that, we probably need a separated patch for this.
>>
> Actually the comment is not in the right commit, the next one is the
> one that uses it. Is that what you mean?


No, it's about the following suggestions.


>
>> And we need to this during vhost-vdpa initialization. If GPA is out of
>> the range, we need to fail the start of vhost-vdpa.


Note that this is for non-IOMMU case. For the case of vIOMMU we probably 
need to validate it against address width or other similar attributes.

Thanks


>>
> Right, that is still to-do.
>
> Maybe a series with just these two commits and failing the start if
> GPA is not in the range, as you say, would help to split the amount of
> changes.
>
> I will send it if no more comments arise about it.
>
> Thanks!
>
>> THanks
>>
>>
>>> Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
>>> ---
>>>    include/hw/virtio/vhost-backend.h |  5 +++++
>>>    hw/virtio/vhost-vdpa.c            | 18 ++++++++++++++++++
>>>    hw/virtio/trace-events            |  1 +
>>>    3 files changed, 24 insertions(+)
>>>
>>> diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h
>>> index 94d3323905..bcb112c166 100644
>>> --- a/include/hw/virtio/vhost-backend.h
>>> +++ b/include/hw/virtio/vhost-backend.h
>>> @@ -36,6 +36,7 @@ struct vhost_vring_addr;
>>>    struct vhost_scsi_target;
>>>    struct vhost_iotlb_msg;
>>>    struct vhost_virtqueue;
>>> +struct vhost_vdpa_iova_range;
>>>
>>>    typedef int (*vhost_backend_init)(struct vhost_dev *dev, void *opaque);
>>>    typedef int (*vhost_backend_cleanup)(struct vhost_dev *dev);
>>> @@ -127,6 +128,9 @@ typedef bool (*vhost_force_iommu_op)(struct vhost_dev *dev);
>>>
>>>    typedef int (*vhost_vring_pause_op)(struct vhost_dev *dev);
>>>
>>> +typedef int (*vhost_get_iova_range)(struct vhost_dev *dev,
>>> +                                    hwaddr *first, hwaddr *last);
>>> +
>>>    typedef struct VhostOps {
>>>        VhostBackendType backend_type;
>>>        vhost_backend_init vhost_backend_init;
>>> @@ -173,6 +177,7 @@ typedef struct VhostOps {
>>>        vhost_get_device_id_op vhost_get_device_id;
>>>        vhost_vring_pause_op vhost_vring_pause;
>>>        vhost_force_iommu_op vhost_force_iommu;
>>> +    vhost_get_iova_range vhost_get_iova_range;
>>>    } VhostOps;
>>>
>>>    extern const VhostOps user_ops;
>>> diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
>>> index 01d2101d09..74fe92935e 100644
>>> --- a/hw/virtio/vhost-vdpa.c
>>> +++ b/hw/virtio/vhost-vdpa.c
>>> @@ -579,6 +579,23 @@ static bool  vhost_vdpa_force_iommu(struct vhost_dev *dev)
>>>        return true;
>>>    }
>>>
>>> +static int vhost_vdpa_get_iova_range(struct vhost_dev *dev,
>>> +                                     hwaddr *first, hwaddr *last)
>>> +{
>>> +    int ret;
>>> +    struct vhost_vdpa_iova_range range;
>>> +
>>> +    ret = vhost_vdpa_call(dev, VHOST_VDPA_GET_IOVA_RANGE, &range);
>>> +    if (ret != 0) {
>>> +        return ret;
>>> +    }
>>> +
>>> +    *first = range.first;
>>> +    *last = range.last;
>>> +    trace_vhost_vdpa_get_iova_range(dev, *first, *last);
>>> +    return ret;
>>> +}
>>> +
>>>    const VhostOps vdpa_ops = {
>>>            .backend_type = VHOST_BACKEND_TYPE_VDPA,
>>>            .vhost_backend_init = vhost_vdpa_init,
>>> @@ -611,4 +628,5 @@ const VhostOps vdpa_ops = {
>>>            .vhost_get_device_id = vhost_vdpa_get_device_id,
>>>            .vhost_vq_get_addr = vhost_vdpa_vq_get_addr,
>>>            .vhost_force_iommu = vhost_vdpa_force_iommu,
>>> +        .vhost_get_iova_range = vhost_vdpa_get_iova_range,
>>>    };
>>> diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
>>> index c62727f879..5debe3a681 100644
>>> --- a/hw/virtio/trace-events
>>> +++ b/hw/virtio/trace-events
>>> @@ -52,6 +52,7 @@ vhost_vdpa_set_vring_call(void *dev, unsigned int index, int fd) "dev: %p index:
>>>    vhost_vdpa_get_features(void *dev, uint64_t features) "dev: %p features: 0x%"PRIx64
>>>    vhost_vdpa_set_owner(void *dev) "dev: %p"
>>>    vhost_vdpa_vq_get_addr(void *dev, void *vq, uint64_t desc_user_addr, uint64_t avail_user_addr, uint64_t used_user_addr) "dev: %p vq: %p desc_user_addr: 0x%"PRIx64" avail_user_addr: 0x%"PRIx64" used_user_addr: 0x%"PRIx64
>>> +vhost_vdpa_get_iova_range(void *dev, uint64_t first, uint64_t last) "dev: %p first: 0x%"PRIx64" last: 0x%"PRIx64
>>>
>>>    # virtio.c
>>>    virtqueue_alloc_element(void *elem, size_t sz, unsigned in_num, unsigned out_num) "elem %p size %zd in_num %u out_num %u"