linux/arch/arm/include/asm/pgtable-nommu.h
Mike Rapoport 974b9b2c68 mm: consolidate pte_index() and pte_offset_*() definitions
All architectures define pte_index() as

	(address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)

and all architectures define pte_offset_kernel() as an entry in the array
of PTEs indexed by the pte_index().

For the most architectures the pte_offset_kernel() implementation relies
on the availability of pmd_page_vaddr() that converts a PMD entry value to
the virtual address of the page containing PTEs array.

Let's move x86 definitions of the PTE accessors to the generic place in
<linux/pgtable.h> and then simply drop the respective definitions from the
other architectures.

The architectures that didn't provide pmd_page_vaddr() are updated to have
that defined.

The generic implementation of pte_offset_kernel() can be overridden by an
architecture and alpha makes use of this because it has special ordering
requirements for its version of pte_offset_kernel().

[rppt@linux.ibm.com: v2]
  Link: http://lkml.kernel.org/r/20200514170327.31389-11-rppt@kernel.org
[rppt@linux.ibm.com: update]
  Link: http://lkml.kernel.org/r/20200514170327.31389-12-rppt@kernel.org
[rppt@linux.ibm.com: update]
  Link: http://lkml.kernel.org/r/20200514170327.31389-13-rppt@kernel.org
[akpm@linux-foundation.org: fix x86 warning]
[sfr@canb.auug.org.au: fix powerpc build]
  Link: http://lkml.kernel.org/r/20200607153443.GB738695@linux.ibm.com

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-10-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00

98 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* arch/arm/include/asm/pgtable-nommu.h
*
* Copyright (C) 1995-2002 Russell King
* Copyright (C) 2004 Hyok S. Choi
*/
#ifndef _ASMARM_PGTABLE_NOMMU_H
#define _ASMARM_PGTABLE_NOMMU_H
#ifndef __ASSEMBLY__
#include <linux/slab.h>
#include <asm/processor.h>
#include <asm/page.h>
/*
* Trivial page table functions.
*/
#define pgd_present(pgd) (1)
#define pgd_none(pgd) (0)
#define pgd_bad(pgd) (0)
#define pgd_clear(pgdp)
#define kern_addr_valid(addr) (1)
/* FIXME */
/*
* PMD_SHIFT determines the size of the area a second-level page table can map
* PGDIR_SHIFT determines what a third-level page table entry can map
*/
#define PGDIR_SHIFT 21
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
/* FIXME */
#define PAGE_NONE __pgprot(0)
#define PAGE_SHARED __pgprot(0)
#define PAGE_COPY __pgprot(0)
#define PAGE_READONLY __pgprot(0)
#define PAGE_KERNEL __pgprot(0)
#define swapper_pg_dir ((pgd_t *) 0)
typedef pte_t *pte_addr_t;
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
*/
#define ZERO_PAGE(vaddr) (virt_to_page(0))
/*
* Mark the prot value as uncacheable and unbufferable.
*/
#define pgprot_noncached(prot) (prot)
#define pgprot_writecombine(prot) (prot)
#define pgprot_device(prot) (prot)
/*
* These would be in other places but having them here reduces the diffs.
*/
extern unsigned int kobjsize(const void *objp);
/*
* All 32bit addresses are effectively valid for vmalloc...
* Sort of meaningless for non-VM targets.
*/
#define VMALLOC_START 0UL
#define VMALLOC_END 0xffffffffUL
#define FIRST_USER_ADDRESS 0UL
#else
/*
* dummy tlb and user structures.
*/
#define v3_tlb_fns (0)
#define v4_tlb_fns (0)
#define v4wb_tlb_fns (0)
#define v4wbi_tlb_fns (0)
#define v6wbi_tlb_fns (0)
#define v7wbi_tlb_fns (0)
#define v3_user_fns (0)
#define v4_user_fns (0)
#define v4_mc_user_fns (0)
#define v4wb_user_fns (0)
#define v4wt_user_fns (0)
#define v6_user_fns (0)
#define xscale_mc_user_fns (0)
#endif /*__ASSEMBLY__*/
#endif /* _ASMARM_PGTABLE_H */