kernel-ark/include/asm-generic/pgtable-nopud.h
Dave McCracken 46a82b2d55 [PATCH] Standardize pxx_page macros
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>
2006-09-26 08:48:51 -07:00

62 lines
1.8 KiB
C

#ifndef _PGTABLE_NOPUD_H
#define _PGTABLE_NOPUD_H
#ifndef __ASSEMBLY__
#define __PAGETABLE_PUD_FOLDED
/*
* Having the pud type consist of a pgd gets the size right, and allows
* us to conceptually access the pgd entry that this pud is folded into
* without casting.
*/
typedef struct { pgd_t pgd; } pud_t;
#define PUD_SHIFT PGDIR_SHIFT
#define PTRS_PER_PUD 1
#define PUD_SIZE (1UL << PUD_SHIFT)
#define PUD_MASK (~(PUD_SIZE-1))
/*
* The "pgd_xxx()" functions here are trivial for a folded two-level
* setup: the pud is never bad, and a pud always exists (as it's folded
* into the pgd entry)
*/
static inline int pgd_none(pgd_t pgd) { return 0; }
static inline int pgd_bad(pgd_t pgd) { return 0; }
static inline int pgd_present(pgd_t pgd) { return 1; }
static inline void pgd_clear(pgd_t *pgd) { }
#define pud_ERROR(pud) (pgd_ERROR((pud).pgd))
#define pgd_populate(mm, pgd, pud) do { } while (0)
/*
* (puds are folded into pgds so this doesn't get actually called,
* but the define is needed for a generic inline function.)
*/
#define set_pgd(pgdptr, pgdval) set_pud((pud_t *)(pgdptr), (pud_t) { pgdval })
static inline pud_t * pud_offset(pgd_t * pgd, unsigned long address)
{
return (pud_t *)pgd;
}
#define pud_val(x) (pgd_val((x).pgd))
#define __pud(x) ((pud_t) { __pgd(x) } )
#define pgd_page(pgd) (pud_page((pud_t){ pgd }))
#define pgd_page_vaddr(pgd) (pud_page_vaddr((pud_t){ pgd }))
/*
* allocating and freeing a pud is trivial: the 1-entry pud is
* inside the pgd, so has no extra memory associated with it.
*/
#define pud_alloc_one(mm, address) NULL
#define pud_free(x) do { } while (0)
#define __pud_free_tlb(tlb, x) do { } while (0)
#undef pud_addr_end
#define pud_addr_end(addr, end) (end)
#endif /* __ASSEMBLY__ */
#endif /* _PGTABLE_NOPUD_H */