From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jambunathan K Subject: Re: xen_create_contiguous_region - Regarding Date: Fri, 06 Apr 2007 18:24:39 +0530 Message-ID: <4616430F.2030507@netxen.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel@lists.xensource.com, sanjeev@netxen.com List-Id: xen-devel@lists.xenproject.org >> pci_map_single() will do what you want automatically. If you really want to >> allocate contiguous memory yourself, allocate it then call >> xen_create_contiguous_region(). Could you please export xen_create_contiguous_region for wider use? Jambunathan K. Keir Fraser wrote: > On 6/4/07 11:46, "Jambunathan K" wrote: > >> 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. > > pci_map_single() will do what you want automatically. If you really want to > allocate contiguous memory yourself, allocate it then call > 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. > > Xen will try to maintain contiguity as far as possible, but it cannot > defragment the memory map. > > -- Keir > > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel >