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Date: Wed, 9 Mar 2016 13:11:40 +0100
From: Olaf Hering <olaf@aepfle.de>
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Subject: [Qemu-devel] bogus bdrv_check_request in bdrv_co_discard
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To: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org

What is the purpose of the bdrv_check_request() call in bdrv_co_discard?

It seems a frontend cant possibly know what the limit is in the
qemu-of-the-day, I found no interface to propagate
BDRV_REQUEST_MAX_SECTORS into the guest.

I think to handle nb_sectors > BDRV_REQUEST_MAX_SECTORS bdrv_co_discard
has to split the request into smaller chunks, just as it does a few
lines down in the function.


Olaf