From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jambunathan K <jambunathan@netxen.com>
Subject: xen_create_contiguous_region  - Regarding
Date: Fri, 06 Apr 2007 16:16:51 +0530
Message-ID: <4616251B.3030000@netxen.com>
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Cc: sanjeev@netxen.com
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Our driver maintains it's own set of bounce buffers rather than relying
on swiotlb.

Some context info could be accessed from this thread in the netdev
mailing list - http://marc.info/?l=linux-netdev&m=116430007806101&w=2

Given that we prefer to maintain our own bounce buffers, I could neither
find a dependable API that let the driver allocate machine contiguous
memory (that could later be *pci_map_singled*) nor find a suitable hook
to xen_create_contiguous_region.

As an aside, is there a tweak to "increase" contiguous memory regions
available so that xen_create_contiguous_regions() succeeds. On DomUs,
when swiotlb is enabled, I see some crashes which I would like to avoid
by redistributing memory resources.

Jambunathan K.