[PATCH v2 hmm 0/9] Small hmm_range_fault() cleanups

[Jason Gunthorpe]

From: Jason Gunthorpe <jgg at mellanox.com>

This is v2 of the first simple series with a few additional patches of little
adjustments.

This needs an additional patch to the hmm tester:

diff --git a/tools/testing/selftests/vm/hmm-tests.c b/tools/testing/selftests/vm/hmm-tests.c
index 033a12c7ab5b6d..da15471a2bbf9a 100644
--- a/tools/testing/selftests/vm/hmm-tests.c
+++ b/tools/testing/selftests/vm/hmm-tests.c
@@ -1274,7 +1274,7 @@ TEST_F(hmm2, snapshot)
 	/* Check what the device saw. */
 	m = buffer->mirror;
 	ASSERT_EQ(m[0], HMM_DMIRROR_PROT_ERROR);
-	ASSERT_EQ(m[1], HMM_DMIRROR_PROT_NONE);
+	ASSERT_EQ(m[1], HMM_DMIRROR_PROT_ERROR);
 	ASSERT_EQ(m[2], HMM_DMIRROR_PROT_ZERO | HMM_DMIRROR_PROT_READ);
 	ASSERT_EQ(m[3], HMM_DMIRROR_PROT_READ);
 	ASSERT_EQ(m[4], HMM_DMIRROR_PROT_WRITE);

v2 changes:
 - Simplify and rename the flags, rework hmm_vma_walk_test in patch 2 (CH)
 - Adjust more comments in patch 3 (CH, Ralph)
 - Put the ugly boolean logic into a function in patch 3 (CH)
 - Update commit message of patch 4 (CH)
 - Adjust formatting in patch 5 (CH)
 Patches 6, 7, 8 are new

v1: https://lore.kernel.org/r/20200320164905.21722-1-jgg@ziepe.ca

Jason Gunthorpe (9):
  mm/hmm: remove pgmap checking for devmap pages
  mm/hmm: return the fault type from hmm_pte_need_fault()
  mm/hmm: remove unused code and tidy comments
  mm/hmm: remove HMM_FAULT_SNAPSHOT
  mm/hmm: remove the CONFIG_TRANSPARENT_HUGEPAGE #ifdef
  mm/hmm: use device_private_entry_to_pfn()
  mm/hmm: do not unconditionally set pfns when returning EBUSY
  mm/hmm: do not set pfns when returning an error code
  mm/hmm: return error for non-vma snapshots

 Documentation/vm/hmm.rst                |  12 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c |   2 +-
 drivers/gpu/drm/nouveau/nouveau_svm.c   |   2 +-
 include/linux/hmm.h                     | 109 +--------
 mm/hmm.c                                | 312 ++++++++++--------------
 5 files changed, 133 insertions(+), 304 deletions(-)

-- 
2.25.2