lkml.org 
[lkml]   [2002]   [Sep]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC] On paging of kernel VM.
Hi,

On Mon, Sep 09, 2002 at 10:20:53AM +0100, David Woodhouse wrote:
> I think I'd like to introduce 'real' VMAs into kernel space, so that areas
> in the vmalloc range can have 'real' vm_ops and more to the point a real
> nopage function.

The alternative is a kmap-style mechanism for temporarily mapping
pages beyond physical memory on demand. That would avoid the space
limits we have on vmalloc etc; there's only a few tens of MB of
address space we can use for mmap tricks in kernel space, so
persistent maps are seriously constrained if you've got a lot of flash
you want to map.

And with a kmap interface, your locking problems are much simpler ---
you can trap accesses at source and you don't have to go hunting ptes
to invalidate.

Cheers,
Stephen
-
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 13:22    [W:0.050 / U:0.628 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site