lkml.org 
[lkml]   [2004]   [Jun]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: DMA API issues
Russell King wrote:
> On Mon, Jun 21, 2004 at 03:35:42PM +0200, Takashi Iwai wrote:
>>Yes, the struct page pointer is needed for vma_ops.nopage in mmap on
>>ALSA. So far, this is broken on some architectures like ARM. We need
>>a proper conversion from virtual/bus pointer to a page struct.
>
>
> Please get away from your nopage implementation. We've been around this
> before with Linus, and the conclusion was that it's up to architectures
> to provide a MMAP method for DMA memory, which _may_ use the nopage
> method if and only if it is appropriate for their implementation.


Can you elaborate?

When I was writing sound/oss/via82cxxx_audio.c, Linus specifically
recommended using ->nopage, which worked out quite well (modulo cleaning
up VM_xxx flags).

Jeff


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:04    [W:0.059 / U:0.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site