mm/ioremap: probe platform for p4d huge map support
authorAnshuman Khandual <anshuman.khandual@arm.com>
Tue, 16 Jul 2019 23:27:33 +0000 (16:27 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 17 Jul 2019 02:23:22 +0000 (19:23 -0700)
commit0f472d04f59ff89d15b2a1c4eafde7317ddd67a2
tree20786684171109ec50859a88c6a354e12e2a8390
parent6b95ab4218bfa59bc315105127ffe03aef3b5742
mm/ioremap: probe platform for p4d huge map support

Finish up what commit c2febafc6773 ("mm: convert generic code to 5-level
paging") started while levelling up P4D huge mapping support at par with
PUD and PMD.  A new arch call back arch_ioremap_p4d_supported() is added
which just maintains status quo (P4D huge map not supported) on x86,
arm64 and powerpc.

When HAVE_ARCH_HUGE_VMAP is enabled its just a simple check from the
arch about the support, hence runtime effects are minimal.

Link: http://lkml.kernel.org/r/1561699231-20991-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/arm64/mm/mmu.c
arch/powerpc/mm/book3s64/radix_pgtable.c
arch/x86/mm/ioremap.c
include/linux/io.h
lib/ioremap.c