Subject: Re: Allocating page frames
To: Eduardo E. Horvath <email@example.com>
From: Jason Thorpe <firstname.lastname@example.org>
Date: 03/28/1997 10:47:59
On Fri, 28 Mar 1997 10:04:47 -0800 (PST)
"Eduardo E. Horvath" <email@example.com> wrote:
> Are there any facilities for allocating physical page frames witout
> mapping them in? Since I will only be accessing the pages though physical
> addresses, I don't want to maintain the info about any virtual mappings
> just so I can free them later on.
I am currently working on a machine-independent interface for this. I
assume you need this for some DMA application, perhaps a framegrabber?
I expect to post another revision of my design document soon, once I
get some of the details worked out. (My i386 bus dma implementation
is about 45% complete, and the allocation of DMA-safe memory is the
> As far as I can see, you can allocate a virtual page using
> vm_page_alloc(), or you can frob the page free list yourself, which is
> breaks modularity. Any other ideas?
Jason R. Thorpe firstname.lastname@example.org
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