linux.git/arch/arc/include/asm/pgtable.h, branch v7.1

arch, mm: consolidate empty_zero_page

2026-04-05T20:53:01+00:00

Reduce 22 declarations of empty_zero_page to 3 and 23 declarations of
ZERO_PAGE() to 4.

Every architecture defines empty_zero_page that way or another, but for the
most of them it is always a page aligned page in BSS and most definitions
of ZERO_PAGE do virt_to_page(empty_zero_page).

Move Linus vetted x86 definition of empty_zero_page and ZERO_PAGE() to the
core MM and drop these definitions in architectures that do not implement
colored zero page (MIPS and s390).

ZERO_PAGE() remains a macro because turning it to a wrapper for a static
inline causes severe pain in header dependencies.

For the most part the change is mechanical, with these being noteworthy:

* alpha: aliased empty_zero_page with ZERO_PGE that was also used for boot
  parameters. Switching to a generic empty_zero_page removes the aliasing
  and keeps ZERO_PGE for boot parameters only
* arm64: uses __pa_symbol() in ZERO_PAGE() so that definition of
  ZERO_PAGE() is kept intact.
* m68k/parisc/um: allocated empty_zero_page from memblock,
  although they do not support zero page coloring and having it in BSS
  will work fine.
* sparc64 can have empty_zero_page in BSS rather allocate it, but it
  can't use virt_to_page() for BSS. Keep it's definition of ZERO_PAGE()
  but instead of allocating it, make mem_map_zero point to
  empty_zero_page.
* sh: used empty_zero_page for boot parameters at the very early boot.
  Rename the parameters page to boot_params_page and let sh use the generic
  empty_zero_page.
* hexagon: had an amusing comment about empty_zero_page

	/* A handy thing to have if one has the RAM. Declared in head.S */

  that unfortunately had to go :)

Link: https://lkml.kernel.org/r/20260211103141.3215197-4-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Acked-by: Helge Deller 		[parisc]
Tested-by: Helge Deller 		[parisc]
Reviewed-by: Christophe Leroy (CS GROUP) 
Acked-by: Dave Hansen 
Acked-by: Catalin Marinas 
Acked-by: Magnus Lindholm 	[alpha]
Acked-by: Dinh Nguyen 	[nios2]
Acked-by: Andreas Larsson 	[sparc]
Acked-by: David Hildenbrand (Arm) 
Acked-by: Liam R. Howlett 
Cc: "Borislav Petkov (AMD)" 
Cc: David S. Miller 
Cc: Geert Uytterhoeven 
Cc: Guo Ren 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Johannes Berg 
Cc: John Paul Adrian Glaubitz 
Cc: Lorenzo Stoakes 
Cc: Madhavan Srinivasan 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Michal Simek 
Cc: Palmer Dabbelt 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Suren Baghdasaryan 
Cc: Vineet Gupta 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

ARC: Replace ASSEMBLY with ASSEMBLER in the non-uapi headers

2025-06-09T16:18:12+00:00

While the GCC and Clang compilers already define __ASSEMBLER__
automatically when compiling assembly code, __ASSEMBLY__ is a
macro that only gets defined by the Makefiles in the kernel.
This can be very confusing when switching between userspace
and kernelspace coding, or when dealing with uapi headers that
rather should use __ASSEMBLER__ instead. So let's standardize on
the __ASSEMBLER__ macro that is provided by the compilers now.

This is a completely mechanical patch (done with a simple "sed -i"
statement).

Cc: linux-snps-arc@lists.infradead.org
Signed-off-by: Thomas Huth 
Signed-off-by: Vineet Gupta

ARC: fix potential build snafu

2021-10-16T01:06:32+00:00

In the big pgtable header split, I inadvertently introduced a couple of
duplicate symbols.

Fixes: fe6cb7b043b69cd9 ("ARC: mm: disintegrate pgtable.h into levels and flags")
Signed-off-by: Vineet Gupta

ARC: mm: disintegrate pgtable.h into levels and flags

2021-08-25T22:53:19+00:00

 - pgtable-bits-arcv2.h (MMU specific page table flags)
 - pgtable-levels.h (paging levels)

No functional changes, but paves way for easy addition of new MMU code
with different bits and levels etc

Signed-off-by: Vineet Gupta

ARC: mm: disintegrate mmu.h (arcv2 bits out)

2021-08-25T22:53:19+00:00

non functional change

Tested-by: kernel test robot 
Signed-off-by: Vineet Gupta

ARC: mm: pmd_populate* to use the canonical set_pmd (and drop pmd_set)

2021-08-24T21:25:48+00:00

Signed-off-by: Vineet Gupta

ARC: ioremap: use more commonly used PAGE_KERNEL based uncached flag

2021-08-24T21:25:48+00:00

and remove the one off uncached definition for ARC

Signed-off-by: Vineet Gupta

ARC: mm: use SCRATCH_DATA0 register for caching pgdir in ARCv2 only

2021-08-24T21:25:48+00:00

MMU SCRATCH_DATA0 register is intended to cache task pgd. However in
ARC700 SMP port, it has to be repurposed for re-entrant interrupt
handling, while UP port doesn't. We currently handle these use-cases
using a fabricated #define which has usual issues of dependency nesting
and obvious ugliness.

So clean this up: for ARC700 don't use to cache pgd (even in UP) and do
the opposite for ARCv2.

And while here, switch to canonical pgd_offset().

Acked-by: Mike Rapoport 
Signed-off-by: Vineet Gupta

ARC: retire MMUv1 and MMUv2 support

2021-08-24T21:25:47+00:00

There's no known/active customer using them with latest kernels anyways.

Removal helps cleanup code and remove the hack for
MMU_VER to MMU_V[3-4] conversion

Signed-off-by: Vineet Gupta

mm/thp: define default pmd_pgtable()

2021-07-01T18:06:03+00:00

Currently most platforms define pmd_pgtable() as pmd_page() duplicating
the same code all over.  Instead just define a default value i.e
pmd_page() for pmd_pgtable() and let platforms override when required via
.  All the existing platform that override pmd_pgtable()
have been moved into their respective  header in order to
precede before the new generic definition.  This makes it much cleaner
with reduced code.

Link: https://lkml.kernel.org/r/1623646133-20306-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual 
Acked-by: Geert Uytterhoeven 
Acked-by: Mike Rapoport 
Cc: Nick Hu 
Cc: Richard Henderson 
Cc: Vineet Gupta 
Cc: Catalin Marinas 
Cc: Will Deacon 
Cc: Guo Ren 
Cc: Brian Cain 
Cc: Geert Uytterhoeven 
Cc: Michal Simek 
Cc: Thomas Bogendoerfer 
Cc: Ley Foon Tan 
Cc: Jonas Bonn 
Cc: Stefan Kristiansson 
Cc: Stafford Horne 
Cc: "James E.J. Bottomley" 
Cc: Michael Ellerman 
Cc: Christophe Leroy 
Cc: Paul Walmsley 
Cc: Palmer Dabbelt 
Cc: Heiko Carstens 
Cc: Yoshinori Sato 
Cc: "David S. Miller" 
Cc: Jeff Dike 
Cc: Thomas Gleixner 
Cc: Chris Zankel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

linux.git/arch/arc/include/asm/pgtable.h, branch v7.1

arch, mm: consolidate empty_zero_page

ARC: Replace __ASSEMBLY__ with __ASSEMBLER__ in the non-uapi headers

ARC: fix potential build snafu

ARC: mm: disintegrate pgtable.h into levels and flags

ARC: mm: disintegrate mmu.h (arcv2 bits out)

ARC: mm: pmd_populate* to use the canonical set_pmd (and drop pmd_set)

ARC: ioremap: use more commonly used PAGE_KERNEL based uncached flag

ARC: mm: use SCRATCH_DATA0 register for caching pgdir in ARCv2 only

ARC: retire MMUv1 and MMUv2 support

mm/thp: define default pmd_pgtable()

ARC: Replace ASSEMBLY with ASSEMBLER in the non-uapi headers