lkml.org 
[lkml]   [1997]   [Dec]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: iopl on ALPHA
On Mon, Dec 15, 1997 at 11:33:50PM +0000, linux-kernel subscriber wrote:

> I'm in the process of updating isapnptools, and just got rid
> of all references to ioperm because iopl is needed anyway on
> x86 systems and gives unrestricted port access.
>
> I have some alpha patches, which don't use iopl, but just
> use ioperm, so the question is, how do IO permissions work
> on Alpha ? (More specifically, does iopl exist and do the
> same thing for alpha systems as x86).
>
> Grepping the kernel sources shows nothing for ioperm or iopl
> for alpha systems, so I guess it's a C library thing. Would
> someone please tell me how IO works on Alpha systems, or
> point me in the right direction.

The same problem also hit's other platforms. Basically the problem
is that supporting ioperm/iopl on non-Intel platforms is suboptimal
in terms of performance. You should probably use /dev/port only
to handle this. The performance hit of /dev/port shouldn't matter
for this case.

Ralf

\
 
 \ /
  Last update: 2005-03-22 13:40    [W:0.368 / U:0.196 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site