[Intel-gfx] [RFC PATCH v2 0/1] Replace shmem memory region and object backend

[Adrian Larumbe]

This patch is a second attempt at eliminating the old shmem memory region
and GEM object backend, in favour of a TTM-based one that is able to manage
objects placed on both system and local memory.

Questions addressed since previous revision:

* Creating an anonymous vfs mount for shmem files in TTM
* Fixing LLC caching properties and bit 17 swizzling before setting a TTM
bo's pages when calling get_pages
* Added handling of phys backend from TTM functions
* Added pread callback to TTM gem object backend
* In shmem_create_from_object, ensuring an shmem object we just got a filp
for has its pages marked dirty and accessed. Otherwise, the engine won't be
able to read the initial state and a GPU hung will ensue

However, one of the issues persists:

Many GPU hungs in machines of GEN <= 5. My assumption is this has something
 to do with a caching pitfall, but everywhere across the TTM backend code
 I've tried to handle object creation and getting its pages with the same
 set of caching and coherency properties as in the old shmem backend.

Adrian Larumbe (1):
  drm/i915: Replace shmem memory region and object backend with TTM

 drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c   |  12 +-
 drivers/gpu/drm/i915/gem/i915_gem_mman.c     |  32 +-
 drivers/gpu/drm/i915/gem/i915_gem_object.h   |   4 +-
 drivers/gpu/drm/i915/gem/i915_gem_phys.c     |  32 +-
 drivers/gpu/drm/i915/gem/i915_gem_shmem.c    | 390 +------------------
 drivers/gpu/drm/i915/gem/i915_gem_ttm.c      | 267 ++++++++++++-
 drivers/gpu/drm/i915/gem/i915_gem_ttm.h      |   3 +
 drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c |   9 +-
 drivers/gpu/drm/i915/gt/shmem_utils.c        |  64 ++-
 drivers/gpu/drm/i915/intel_memory_region.c   |   7 +-
 10 files changed, 398 insertions(+), 422 deletions(-)

-- 
2.35.1