suggesting wording fixes for virtio-spec 0.9.5

[Laszlo Ersek <lersek@redhat.com>]

Hi,

(I'm not subscribed to either list,)

using the word "descriptor" is misleading in the following sections:

  2.4.1.2 Updating The Available Ring

  [...] However, in general we can add many descriptors before we
  update the \x10idx\x11 fi\x1celd (at which point they become visible to the
  device), so we keep a counter of how many we've added: [...]

and

  2.4.1.3 Updating The Index Field

  Once the idx fi\x1celd of the virtqueue is updated, the device will be
  able to access the descriptor entries we've created and the memory
  they refer to. [...]

(The word "descriptor" in the above language is the reason I
mis-implemented the virtio-blk guest driver in OVMF.)

In fact the available ring tracks *head* descriptors only. I suggest

  s/many descriptors/many separate descriptor chains/
  s/descriptor entries/separate descriptor chains/

for the above.

Similarly, 2.3.4 Available Ring should start with something like

  The available ring describes what descriptor chains we are off^[ering
  the device: each entry of the available ring refers to the head
  descriptor of a separate descriptor chain.

Thanks
Laszlo