From mboxrd@z Thu Jan  1 00:00:00 1970
From: Venkatesh Srinivas <venkateshs@google.com>
Subject: Re: [PATCH 40/41] net/virtio: use contiguous allocation
 for DMA memory
Date: Sat, 3 Mar 2018 10:52:09 -0600
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To: Anatoly Burakov <anatoly.burakov@intel.com>
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On Sat, Mar 3, 2018 at 7:46 AM, Anatoly Burakov
<anatoly.burakov@intel.com> wrote:
> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
> ---
>
> Notes:
>     Not sure if virtio needs to allocate DMA-capable memory,
>     being a software driver and all. Corrections welcome.

Reviewed-by: Venkatesh Srinivas <venkateshs@google.com>

1. The first change is correct - virtio rings need to be contiguous in
guest physical address
    space.

2. The second change - virtio_tx_region contains both a virtio_net_hdr
and indirect table.
    virtio devices require virtio_net_hdr to be contiguous (in pre-1.0
devices w/o F_ANY_LAYOUT)
    but do not require the indirect table to be contiguous w/
virtio_net_hdr. You may want this to
    avoid splitting up the structure though.

HTH,
-- vs;