Re: [Qemu-block] [Qemu-devel] [PATCH v6 16/29] libqos: Use explicit QTestState for virtio operations

[Paolo Bonzini]

>  typedef struct QVirtioDevice {
>      const QVirtioBus *bus;
> +    QTestState *qts;
>      /* Device type */
>      uint16_t device_type;
>  } QVirtioDevice;
> @@ -35,12 +36,14 @@ typedef struct QVirtQueue {
>      uint16_t last_used_idx;
>      bool indirect;
>      bool event;
> +    QTestState *qts;
>  } QVirtQueue;
>
>  typedef struct QVRingIndirectDesc {
>      uint64_t desc; /* This points to an array fo struct vring_desc */
>      uint16_t index;
>      uint16_t elem;
> +    QTestState *qts;
>  } QVRingIndirectDesc;

Adding QTestState to QVRingIndirectDesc and QVirtQueue sounds somewhat
ugly to me. I think they should either rather have a pointer to the
associated QVirtioDevice, or the functions where this is needed
(qvring_init() for example) should get a "QTestState *" parameter instead.

I agree with Thomas and even extend it to QVirtioDevice. If there is a has-a hierarchy between libqos objects, only the topmost one (such as the virtio mmio bus device, and the PCI host bridge---or possibly even the machine object exclusively) should have a QTestState. Everyone else can access it implicitly through operations on its bus.

Test code on the other hand can use global_qtest implicitly when they prepare/read buffers that the devices do DMA from/to.

Paolo

Just my 0.02 €.

 Thomas