Date: Thu, 17 Feb 2005 13:31:46 -0600 (CST) From: Mike Silbersack <silby@silby.com> To: Gerald Heinig <gheinig@syskonnect.de> Cc: hackers@freebsd.org Subject: Re: bus_dmamem_alloc strangeness Message-ID: <20050217133029.U43225@odysseus.silby.com> In-Reply-To: <4214D6A0.9010803@syskonnect.de> References: <4214D6A0.9010803@syskonnect.de>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, 17 Feb 2005, Gerald Heinig wrote: > Hi hackers, > > I've come across weird behaviour in bus_dmamem_alloc() whilst trying to > allocate small memory blocks (less than PAGE_SIZE) which have to be > aligned to PAGE_SIZE. > My segment size is 2048, my maximum number of segments is 1 (it MUST be > contiguous), my max. total segment size is also 2048 and my alignment > constraint is 4k (PAGE_SIZE). However, the DMA memory I'm getting from > bus_dmamem_alloc() is NOT aligned to 4k. You should e-mail Scott Long (scottl@freebsd.org) about this directly. I believe that he has been working on related changes to busdma recently, but I'm not sure which branches have received his improvements. Mike "Silby" Silbersack
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20050217133029.U43225>