Thomas Hellstrom 1df6a2ebd7 drm/ttm: Fix two race conditions + fix busy codepaths
This fixes a race pointed out by Dave Airlie where we don't take a buffer
object about to be destroyed off the LRU lists properly. It also fixes a rare
case where a buffer object could be destroyed in the middle of an
accelerated eviction.

The patch also adds a utility function that can be used to prematurely
release GPU memory space usage of an object waiting to be destroyed.
For example during eviction or swapout.

The above mentioned commit didn't queue the buffer on the delayed destroy
list under some rare circumstances. It also didn't completely honor the
remove_all parameter.

Fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=615505
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=591061

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-06 09:04:43 +10:00
..
2010-05-18 15:57:05 +10:00
2010-09-24 10:10:23 +10:00
2010-08-10 10:47:00 +10:00
2010-05-18 15:57:05 +10:00
2010-08-10 08:20:20 +10:00
2010-09-28 09:14:34 +10:00
2010-08-04 09:46:06 +10:00

************************************************************
* For the very latest on DRI development, please see:      *
*     http://dri.freedesktop.org/                          *
************************************************************

The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).

The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:

    1. The DRM provides synchronized access to the graphics hardware via
       the use of an optimized two-tiered lock.

    2. The DRM enforces the DRI security policy for access to the graphics
       hardware by only allowing authenticated X11 clients access to
       restricted regions of memory.

    3. The DRM provides a generic DMA engine, complete with multiple
       queues and the ability to detect the need for an OpenGL context
       switch.

    4. The DRM is extensible via the use of small device-specific modules
       that rely extensively on the API exported by the DRM module.


Documentation on the DRI is available from:
    http://dri.freedesktop.org/wiki/Documentation
    http://sourceforge.net/project/showfiles.php?group_id=387
    http://dri.sourceforge.net/doc/

For specific information about kernel-level support, see:

    The Direct Rendering Manager, Kernel Support for the Direct Rendering
    Infrastructure
    http://dri.sourceforge.net/doc/drm_low_level.html

    Hardware Locking for the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/hardware_locking_low_level.html

    A Security Analysis of the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/security_low_level.html