linux/arch/openrisc/include/asm
Mike Rapoport (Microsoft) 6215d9f447 arch, mm: consolidate empty_zero_page
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) <rppt@kernel.org>
Acked-by: Helge Deller <deller@gmx.de>		[parisc]
Tested-by: Helge Deller <deller@gmx.de>		[parisc]
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Magnus Lindholm <linmag7@gmail.com>	[alpha]
Acked-by: Dinh Nguyen <dinguyen@kernel.org>	[nios2]
Acked-by: Andreas Larsson <andreas@gaisler.com>	[sparc]
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:01 -07:00
..
bitops openrisc: Add __attribute_const__ to ffs()-family implementations 2025-09-08 14:58:51 -07:00
asm-offsets.h
atomic.h locking/atomic: make atomic*_{cmp,}xchg optional 2023-06-05 09:57:14 +02:00
barrier.h openrisc: define arch-specific version of nop() 2026-01-20 19:24:05 +00:00
bitops.h include: move find.h from asm_generic to linux 2022-01-15 08:47:31 -08:00
bug.h openrisc: Add prototype for die to bug.h 2023-08-21 08:15:25 +01:00
cache.h
cacheflush.h mm: introduce memdesc_flags_t 2025-09-13 16:55:07 -07:00
cmpxchg.h locking/arch: Rename all internal __xchg() names to __arch_xchg() 2023-04-29 09:08:44 +02:00
cpuinfo.h openrisc: Introduce new utility functions to flush and invalidate caches 2025-04-20 07:06:54 +01:00
delay.h
elf.h
fixmap.h openrisc: Add text patching API support 2025-09-11 11:27:59 +01:00
fpu.h openrisc: Move FPU state out of pt_regs 2024-04-15 15:20:39 +01:00
futex.h
insn-def.h openrisc: Add jump label support 2025-09-11 11:27:59 +01:00
io.h openrisc: mm: convert to GENERIC_IOREMAP 2023-08-18 10:12:34 -07:00
irq.h
irqflags.h
jump_label.h openrisc: Add jump label support 2025-09-11 11:27:59 +01:00
Kbuild openrisc: Add text patching API support 2025-09-11 11:27:59 +01:00
linkage.h
mmu_context.h
mmu.h openrisc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers 2025-06-07 06:44:28 +01:00
page.h treewide: provide a generic clear_user_page() variant 2026-01-20 19:24:39 -08:00
pgalloc.h mm: pgtable: convert some architectures to use tlb_remove_ptdesc() 2025-04-01 15:17:13 -07:00
pgtable.h arch, mm: consolidate empty_zero_page 2026-04-05 13:53:01 -07:00
processor.h openrisc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers 2025-06-07 06:44:28 +01:00
ptrace.h openrisc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers 2025-06-07 06:44:28 +01:00
serial.h
setup.h openrisc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers 2025-06-07 06:44:28 +01:00
smp.h openrisc: Fix IPIs on simple multicore systems 2026-01-16 16:38:56 +00:00
spr_defs.h
spr.h
string.h
syscall.h syscall.h: introduce syscall_set_nr() 2025-05-11 17:48:15 -07:00
syscalls.h openrisc: convert to generic syscall table 2024-07-10 14:23:38 +02:00
text-patching.h openrisc: Add text patching API support 2025-09-11 11:27:59 +01:00
thread_info.h openrisc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers 2025-06-07 06:44:28 +01:00
time.h
timex.h openrisc: start CPU timer early in boot 2022-05-13 23:59:23 +02:00
tlb.h
tlbflush.h
uaccess.h uaccess: remove CONFIG_SET_FS 2022-02-25 09:36:06 +01:00
unistd.h openrisc: convert to generic syscall table 2024-07-10 14:23:38 +02:00
unwinder.h
vmalloc.h