drm: use anon-inode instead of relying on cdevs
authorDavid Herrmann <dh.herrmann@gmail.com>
Fri, 3 Jan 2014 13:24:19 +0000 (14:24 +0100)
committerDavid Herrmann <dh.herrmann@gmail.com>
Sun, 16 Mar 2014 11:23:33 +0000 (12:23 +0100)
commit6796cb16c088905bf3af40548fda68c09e6f6ee5
treed40162f17dad7b54ac63feaf62b7c84493556f5a
parent31bbe16f6d88622d6731fa2cb4ab38d57d844ac1
drm: use anon-inode instead of relying on cdevs

DRM drivers share a common address_space across all character-devices of a
single DRM device. This allows simple buffer eviction and mapping-control.
However, DRM core currently waits for the first ->open() on any char-dev
to mark the underlying inode as backing inode of the device. This delayed
initialization causes ugly conditions all over the place:
  if (dev->dev_mapping)
    do_sth();

To avoid delayed initialization and to stop reusing the inode of the
char-dev, we allocate an anonymous inode for each DRM device and reset
filp->f_mapping to it on ->open().

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
15 files changed:
drivers/gpu/drm/ast/ast_ttm.c
drivers/gpu/drm/bochs/bochs_mm.c
drivers/gpu/drm/cirrus/cirrus_ttm.c
drivers/gpu/drm/drm_fops.c
drivers/gpu/drm/drm_stub.c
drivers/gpu/drm/i915/i915_gem.c
drivers/gpu/drm/mgag200/mgag200_ttm.c
drivers/gpu/drm/nouveau/nouveau_gem.c
drivers/gpu/drm/omapdrm/omap_gem.c
drivers/gpu/drm/qxl/qxl_object.c
drivers/gpu/drm/qxl/qxl_ttm.c
drivers/gpu/drm/radeon/radeon_object.c
drivers/gpu/drm/radeon/radeon_ttm.c
drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
include/drm/drmP.h