Files
erofs-linux/include/asm-generic/pgtable-nopmd.h
T
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().

[[email protected]: v2]
  Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: update]
  Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: update]
  Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: fix x86 warning]
[[email protected]: fix powerpc build]
  Link: http://lkml.kernel.org/r/[email protected]

Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Cain <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Chris Zankel <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Greentime Hu <[email protected]>
Cc: Greg Ungerer <[email protected]>
Cc: Guan Xuetao <[email protected]>
Cc: Guo Ren <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Ley Foon Tan <[email protected]>
Cc: Mark Salter <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Nick Hu <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Rich Felker <[email protected]>
Cc: Russell King <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Vincent Chen <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09 09:39:14 -07:00

72 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PGTABLE_NOPMD_H
#define _PGTABLE_NOPMD_H
#ifndef __ASSEMBLY__
#include <asm-generic/pgtable-nopud.h>
struct mm_struct;
#define __PAGETABLE_PMD_FOLDED 1
/*
* Having the pmd type consist of a pud gets the size right, and allows
* us to conceptually access the pud entry that this pmd is folded into
* without casting.
*/
typedef struct { pud_t pud; } pmd_t;
#define PMD_SHIFT PUD_SHIFT
#define PTRS_PER_PMD 1
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
/*
* The "pud_xxx()" functions here are trivial for a folded two-level
* setup: the pmd is never bad, and a pmd always exists (as it's folded
* into the pud entry)
*/
static inline int pud_none(pud_t pud) { return 0; }
static inline int pud_bad(pud_t pud) { return 0; }
static inline int pud_present(pud_t pud) { return 1; }
static inline void pud_clear(pud_t *pud) { }
#define pmd_ERROR(pmd) (pud_ERROR((pmd).pud))
#define pud_populate(mm, pmd, pte) do { } while (0)
/*
* (pmds are folded into puds so this doesn't get actually called,
* but the define is needed for a generic inline function.)
*/
#define set_pud(pudptr, pudval) set_pmd((pmd_t *)(pudptr), (pmd_t) { pudval })
static inline pmd_t * pmd_offset(pud_t * pud, unsigned long address)
{
return (pmd_t *)pud;
}
#define pmd_offset pmd_offset
#define pmd_val(x) (pud_val((x).pud))
#define __pmd(x) ((pmd_t) { __pud(x) } )
#define pud_page(pud) (pmd_page((pmd_t){ pud }))
#define pud_page_vaddr(pud) (pmd_page_vaddr((pmd_t){ pud }))
/*
* allocating and freeing a pmd is trivial: the 1-entry pmd is
* inside the pud, so has no extra memory associated with it.
*/
#define pmd_alloc_one(mm, address) NULL
static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
{
}
#define pmd_free_tlb(tlb, x, a) do { } while (0)
#undef pmd_addr_end
#define pmd_addr_end(addr, end) (end)
#endif /* __ASSEMBLY__ */
#endif /* _PGTABLE_NOPMD_H */