mm: replace pmd_write with pmd_access_permitted in fault + gup paths
authorDan Williams <dan.j.williams@intel.com>
Thu, 30 Nov 2017 00:10:18 +0000 (16:10 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 30 Nov 2017 02:40:42 +0000 (18:40 -0800)
commitc7da82b894e9eef60a04a15f065a8502341bf13b
treec59fd3cca98b6247bcd36f2cea370c3ce746b4e2
parente7fe7b5cae90cf85bb6fed5ec5d4c5cf311a4fe9
mm: replace pmd_write with pmd_access_permitted in fault + gup paths

The 'access_permitted' helper is used in the gup-fast path and goes
beyond the simple _PAGE_RW check to also:

 - validate that the mapping is writable from a protection keys
   standpoint

 - validate that the pte has _PAGE_USER set since all fault paths where
   pmd_write is must be referencing user-memory.

Link: http://lkml.kernel.org/r/151043111049.2842.15241454964150083466.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/sparc/mm/gup.c
fs/dax.c
mm/hmm.c
mm/huge_memory.c
mm/memory.c