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From: Peter Lieven <pl@kamp.de>
Message-ID: <577A6955.6020603@kamp.de>
Date: Mon, 4 Jul 2016 15:49:09 +0200
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Subject: [Qemu-devel] Regression: block: Add .bdrv_co_pwrite_zeroes()
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To: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Cc: Eric Blake <eblake@redhat.com>, Kevin Wolf <kwolf@redhat.com>

Hi,

the above commit:

commit d05aa8bb4a8b6aa9a915ec5074fb12ae632d2323
Author: Eric Blake <eblake@redhat.com>
Date:   Wed Jun 1 15:10:03 2016 -0600

     block: Add .bdrv_co_pwrite_zeroes()

introduces a regression (at least for me).

The Limits from the iSCSI Block Limits VPD have no requirement of being a power of two.
We use Dell Equallogic iSCSI SANs for instance. They have an internal page size of 15MB. And
they advertise this page size as max_ws_len, opt_transfer_len and opt_discard_alignment.

I think we cannot assert that that these alignments are a power of 2.

Peter