* Michael S. Tsirkin <m...@redhat.com> [2020-04-28 16:41:04]:
> > Won't we still need some changes to virtio to make use of its own pool (to
> > bounce buffers)? Something similar to its own DMA ops proposed in this
> > patch?
>
> If you are doing this for all devices, you need to either find a way
> to do this without chaning DMA ops, or by doing some automatic change
> to all drivers.
Ok thanks for this input. I will see how we can obfuscate this in DMA APIs
itself.
Can you also comment on the virtio transport problem I cited? The hypervisor we
are dealing with does not support MMIO transport. It supports message queue
send/recv and also doorbell, which I think can be used if we can make some
change like this to virtio_mmio.c:
+static inline u32
+virtio_readl(struct virtio_mmio_device *vm_dev, u32 reg_offset)
+{
+ return vm_dev->mmio_ops->readl(vm_dev, reg_offset);
+}
+
+static inline void
+virtio_writel(struct virtio_mmio_device *vm_dev, u32 reg_offset, u32 data)
+{
+ vm_dev->mmio_ops->writel(vm_dev, reg_offset, data);
+}
/* Check magic value */
- magic = readl(vm_dev->base + VIRTIO_MMIO_MAGIC_VALUE);
+ magic = vrito_readl(vm_dev, VIRTIO_MMIO_MAGIC_VALUE);
mmio_ops->readl on most platforms can default to readl itself, while on a
platform like us, it can boil down to message_queue send/recv. Would such a
change be acceptable?
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation
