On 06/01/2011 05:36 PM, Michael S. Tsirkin wrote:
>
> So, if I am going to give this liberty with buffers to the driver, I
> _have_ to keep the size information. Otherwise, I agree that it is
> redundant and I will remove it. What poison do you prefer?
>
Ah, I think I understand now. Both sense and data have in
fields that might only be used partially?
In that case I think I agree: it's best to require the use of separate
buffers for them, in this way used len will give you useful information
and you won't need sense_len and data_len: just a flag to
mark the fact that there *is* a sense buffer following.
And the num field does that.
Do you mean to use the virtio iovec length to determine information
about the message (like splitting it into buffers)?
I think that's a bad idea. Splitting into buffers is a function of
memory management. For example, a driver in userspace (or a nested
guest) will have additional fragmentation into 4K pages after it passes
through the iommu.
Let's not mix layers here.
--
error compiling committee.c: too many arguments to function
