linux/drivers/gpu/drm
Eric Anholt bd95e0a4a6 i915: Remove racy delayed vblank swap ioctl.
When userland detected that this ioctl was supported (by version number check),
it used it in a racy way -- dispatch delayed swap, wait for vblank, continue
rendering. As there was no mechanism for it to wait for the swap to finish,
sometimes it would render before the swap and garbage would be displayed on
the screen.

By removing the ioctl and returning -EINVAL, userland returns to its previous,
correct rendering path of waiting for a vblank then dispatching a swap.  The
only path that could have used this ioctl correctly was page flipping, which
relied on only one client running and emitting wait-for-vblank-before-rendering
in the command stream.  That path also falls back correctly, at the performance
cost of not being able to queue up rendering before the flip occurs.

Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>
2008-11-11 17:44:22 +10:00
..
i810 drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
i830 drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
i915 i915: Remove racy delayed vblank swap ioctl. 2008-11-11 17:44:22 +10:00
mga drm: kill drm_device->irq 2008-10-18 07:10:53 +10:00
r128 drm: kill drm_device->irq 2008-10-18 07:10:53 +10:00
radeon drm/radeon: fixup further bus mastering confusion. 2008-10-28 07:48:34 +10:00
savage drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
sis SiS DRM: fix a pointer cast warning 2008-10-18 07:10:10 +10:00
tdfx drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
via drm: kill drm_device->irq 2008-10-18 07:10:53 +10:00
ati_pcigart.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_agpsupport.c i915: Map status page cached for chips with GTT-based HWS location. 2008-10-18 07:10:53 +10:00
drm_auth.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_bufs.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_cache.c drm: wbinvd is cache coherent. 2008-10-18 07:10:53 +10:00
drm_context.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_dma.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_drawable.c drm: Avoid oops in DRM_IOCTL_RM_DRAW if a bad handle is supplied. 2008-10-23 13:46:54 +10:00
drm_drv.c drm: Add GEM ("graphics execution manager") to i915 driver. 2008-10-18 07:10:12 +10:00
drm_fops.c saner FASYNC handling on file close 2008-11-01 09:49:46 -07:00
drm_gem.c DRM: Return -EBADF on bad object in flink, and return curent name if it exists. 2008-10-18 07:10:52 +10:00
drm_hashtab.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_ioc32.c drm: Add 32-bit compatibility for DRM_IOCTL_UPDATE_DRAW. 2008-10-23 13:46:33 +10:00
drm_ioctl.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_irq.c drm: Remove two leaks of vblank reference count in error paths. 2008-10-23 13:42:27 +10:00
drm_lock.c drm/i915: hold dev->struct_mutex and DRM lock during vblank ring operations 2008-10-23 13:45:56 +10:00
drm_memory.c drm: Add GEM ("graphics execution manager") to i915 driver. 2008-10-18 07:10:12 +10:00
drm_mm.c drm: Add GEM ("graphics execution manager") to i915 driver. 2008-10-18 07:10:12 +10:00
drm_pci.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_proc.c i915: Fix format string warnings on x86-64. 2008-10-23 13:42:27 +10:00
drm_scatter.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_sman.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
drm_stub.c drm: kill drm_device->irq 2008-10-18 07:10:53 +10:00
drm_sysfs.c drm: fix sysfs error path. 2008-10-18 07:10:11 +10:00
drm_vm.c drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00
Kconfig Export tiny shmem_file_setup for DRM-GEM 2008-10-20 16:17:42 -07:00
Makefile drm: Add GEM ("graphics execution manager") to i915 driver. 2008-10-18 07:10:12 +10:00
README.drm drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +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