mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-27 13:05:03 +08:00
46a82b2d55
One of the changes necessary for shared page tables is to standardize the pxx_page macros. pte_page and pmd_page have always returned the struct page associated with their entry, while pte_page_kernel and pmd_page_kernel have returned the kernel virtual address. pud_page and pgd_page, on the other hand, return the kernel virtual address. Shared page tables needs pud_page and pgd_page to return the actual page structures. There are very few actual users of these functions, so it is simple to standardize their usage. Since this is basic cleanup, I am submitting these changes as a standalone patch. Per Hugh Dickins' comments about it, I am also changing the pxx_page_kernel macros to pxx_page_vaddr to clarify their meaning. Signed-off-by: Dave McCracken <dmccr@us.ibm.com> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
66 lines
1.8 KiB
C
66 lines
1.8 KiB
C
#ifndef _PGTABLE_NOPMD_H
|
|
#define _PGTABLE_NOPMD_H
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#include <asm-generic/pgtable-nopud.h>
|
|
|
|
#define __PAGETABLE_PMD_FOLDED
|
|
|
|
/*
|
|
* 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_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
|
|
#define pmd_free(x) do { } while (0)
|
|
#define __pmd_free_tlb(tlb, x) do { } while (0)
|
|
|
|
#undef pmd_addr_end
|
|
#define pmd_addr_end(addr, end) (end)
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
|
|
#endif /* _PGTABLE_NOPMD_H */
|