linux-mips
[Top] [All Lists]

Re: pci_alloc_consistent usage

To: Ralf Baechle <ralf@linux-mips.org>
Subject: Re: pci_alloc_consistent usage
From: Christoph Hellwig <hch@infradead.org>
Date: Tue, 27 May 2003 12:33:29 +0100
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>, wgowcher@yahoo.com, linux-mips@linux-mips.org
In-reply-to: <20030527112237.GA24905@linux-mips.org>; from ralf@linux-mips.org on Tue, May 27, 2003 at 01:22:37PM +0200
Original-recipient: rfc822;linux-mips@linux-mips.org
References: <20030523215935.71373.qmail@web11901.mail.yahoo.com> <20030527091740.GA23296@linux-mips.org> <20030527.190749.39150100.nemoto@toshiba-tops.co.jp> <20030527115322.A7124@infradead.org> <20030527112237.GA24905@linux-mips.org>
Sender: linux-mips-bounce@linux-mips.org
User-agent: Mutt/1.2.5.1i
On Tue, May 27, 2003 at 01:22:37PM +0200, Ralf Baechle wrote:
> [...]
> portably refer to any piece of memory.  If you have a cpu pointer
> (which may be validly DMA'd too) you may easily obtain the page
> and offset using something like this:
>                                                                               
>   
>         struct page *page = virt_to_page(ptr);
>         unsigned long offset = ((unsigned long)ptr & ~PAGE_MASK);
> [...]
> 
> While it's officially documented I still don't like it.

Hmm, I remembered that some ports used vmalloc-like allocators for
this and virt_to_page doesn't work for those..


<Prev in Thread] Current Thread [Next in Thread>