Date: Fri, 28 Feb 1997 10:15:22 -0700 (MST) From: Terry Lambert <terry@lambert.org> To: dg@root.com Cc: jpt@msc.edu, hackers@FreeBSD.ORG Subject: Re: Assumptions about kmem_malloc()... Message-ID: <199702281715.KAA02143@phaeton.artisoft.com> In-Reply-To: <199702280129.RAA05746@root.com> from "David Greenman" at Feb 27, 97 05:29:28 pm
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> > o What other hidden gotchas are there in working with DMA and > >device drivers? > > Well, contiguous allocation is always the most common thing to get people. > :-) The only other thing you should be aware of is that allocation of > contiguous memory during normal system operation isn't guaranteed (in fact, > will likely fail)...so you should allocate whatever you need contiguous > during the device attach and olny release it later if you know you won't > need it. Why doesn't it push pages around to get a contiguous space so that it won't fail? Regards, Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.
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