linux/arch/m68k
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
..
68000 m68knommu: Replace deprecated strcpy with strscpy in init_ucsimm 2026-01-27 12:38:52 +10:00
amiga Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
apollo m68k: remove unneeded tty includes 2025-06-17 13:42:33 +02:00
atari Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
bvme6000 m68k: Replace GPL 2.0+ README.legal boilerplate with SPDX 2023-10-06 10:03:04 +02:00
coldfire m68k: coldfire: remove creating a fixed phy 2025-11-04 18:46:13 -08:00
configs m68knommu: updates and fixes for v7.0 2026-02-15 19:45:00 -08:00
emu Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
fpsp040 m68k: fpsp040: Fix indentation by 5 spaces 2023-10-16 14:30:40 +02:00
hp300 serial: 8250: Move hp300_setup_serial_console() to <linux/serial_8250.h> 2024-01-27 19:01:39 -08:00
ifpsp060 m68k: Replace GPL 2.0+ README.legal boilerplate with SPDX 2023-10-06 10:03:04 +02:00
include arch, mm: consolidate empty_zero_page 2026-04-05 13:53:01 -07:00
kernel kbuild: Split .modinfo out from ELF_DETAILS 2026-02-26 11:50:19 -07:00
lib m68k: nommu: fix memmove() with differently aligned src and dest for 68000 2026-01-27 12:38:52 +10:00
mac m68k updates for v6.17 2025-07-29 20:19:47 -07:00
math-emu m68k: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers 2025-07-06 12:50:50 +02:00
mm arch, mm: consolidate empty_zero_page 2026-04-05 13:53:01 -07:00
mvme16x m68k: mvme147, mvme16x: Adopt rtc-m48t59 platform driver 2024-11-22 20:59:40 +01:00
mvme147 RTC for 6.13 2024-11-30 11:18:16 -08:00
q40 m68k: remove unneeded tty includes 2025-06-17 13:42:33 +02:00
sun3 m68k: sun3: Replace vsprintf() with bounded vsnprintf() 2026-01-26 12:26:01 +01:00
sun3x m68k: sun3/3x: Add and use "sun3.h" 2023-10-06 10:03:04 +02:00
tools/amiga
virt
install.sh kbuild: Abort make on install failures 2024-07-20 13:34:54 +09:00
Kbuild
Kconfig m68k: Enable dead code elimination 2025-07-06 12:50:50 +02:00
Kconfig.bus
Kconfig.cpu m68k: Select M68020 as fallback for classic 2024-11-06 15:10:14 +01:00
Kconfig.debug m68k: Don't unregister boot console needlessly 2025-07-06 12:50:50 +02:00
Kconfig.devices m68k: /proc/hardware should depend on PROC_FS 2023-02-13 11:34:49 +01:00
Kconfig.machine m68k: Move Sun 3 into a top-level platform option 2024-11-06 15:10:14 +01:00
Makefile kbuild: use 4-space indentation when followed by conditionals 2024-02-15 06:05:44 +09:00