linux-stable/arch/x86/include/asm/pgtable_32_types.h
Ingo Molnar 186525bd6b mm, x86/mm: Untangle address space layout definitions from basic pgtable type definitions
- Untangle the somewhat incestous way of how VMALLOC_START is used all across the
  kernel, but is, on x86, defined deep inside one of the lowest level page table headers.
  It doesn't help that vmalloc.h only includes a single asm header:

     #include <asm/page.h>           /* pgprot_t */

  So there was no existing cross-arch way to decouple address layout
  definitions from page.h details. I used this:

   #ifndef VMALLOC_START
   # include <asm/vmalloc.h>
   #endif

  This way every architecture that wants to simplify page.h can do so.

- Also on x86 we had a couple of LDT related inline functions that used
  the late-stage address space layout positions - but these could be
  uninlined without real trouble - the end result is cleaner this way as
  well.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-10 10:12:55 +01:00

23 lines
634 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_PGTABLE_32_TYPES_H
#define _ASM_X86_PGTABLE_32_TYPES_H
/*
* The Linux x86 paging architecture is 'compile-time dual-mode', it
* implements both the traditional 2-level x86 page tables and the
* newer 3-level PAE-mode page tables.
*/
#ifdef CONFIG_X86_PAE
# include <asm/pgtable-3level_types.h>
# define PMD_SIZE (1UL << PMD_SHIFT)
# define PMD_MASK (~(PMD_SIZE - 1))
#else
# include <asm/pgtable-2level_types.h>
#endif
#define pgtable_l5_enabled() 0
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE - 1))
#endif /* _ASM_X86_PGTABLE_32_TYPES_H */