lkml.org 
[lkml]   [1999]   [Nov]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: map_user_kiobuf question
> What type of address gets passed to the third argument of
> map_user_kiobuf?
>
> can I do something like
>
> addr = vmalloc (size);
> ...
> map_user_kiobuf (xxx, iobuf, (unsigned long) addr, xxx);
> [ ... mess around with iobuf'd pages ... ]
> unmap_kiobuf (iobuf);

An address from the user space. For example the 2nd argument of
a read() [both the user space system call and a character device
read]. Not sure about the vmalloc() aspect.

Just to save you a little time, you may be needing the
recently added page_address() macro as well to get a 32 bit
address back out of a page object suitable for a DMA chip.


Doug Gilbert

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

\
 
 \ /
  Last update: 2005-03-22 13:54    [W:0.054 / U:0.268 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site