Like cleanup in an earlier patch, the code becomes much more readable,
and easier to extend if we extract out helper functions for the various
stages of init.
Note that with this patch it becomes really simple, and tempting to begin
using the 'goto out' idiom with explicit free/fini semantics. I've
kept the error path as similar as possible to the cleanup() function to
make sure cleanup is as robust as possible
v2: Remove comment "NB:From here on, ppgtt->base.cleanup() should
function properly"
Update commit message to reflect above
v3: Rebased on top of bugfixes found in the previous patch by Imre
Moved number of pd pages assertion to the proper place (Imre)
v4:
Allocate dma address space for num_pd_pages, not num_pd_entries (Ben)
Don't use gen8_pt_dma_addr after free on error path (Imre)
With new fix from v4 of the previous patch.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
************************************************************
* 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