remarkable-linux/include/asm-generic/pgtable-nopud.h
Benjamin Herrenschmidt 9e1b32caa5 mm: Pass virtual address to [__]p{te,ud,md}_free_tlb()
mm: Pass virtual address to [__]p{te,ud,md}_free_tlb()

Upcoming paches to support the new 64-bit "BookE" powerpc architecture
will need to have the virtual address corresponding to PTE page when
freeing it, due to the way the HW table walker works.

Basically, the TLB can be loaded with "large" pages that cover the whole
virtual space (well, sort-of, half of it actually) represented by a PTE
page, and which contain an "indirect" bit indicating that this TLB entry
RPN points to an array of PTEs from which the TLB can then create direct
entries. Thus, in order to invalidate those when PTE pages are deleted,
we need the virtual address to pass to tlbilx or tlbivax instructions.

The old trick of sticking it somewhere in the PTE page struct page sucks
too much, the address is almost readily available in all call sites and
almost everybody implemets these as macros, so we may as well add the
argument everywhere. I added it to the pmd and pud variants for consistency.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: David Howells <dhowells@redhat.com> [MN10300 & FRV]
Acked-by: Nick Piggin <npiggin@suse.de>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-27 12:10:38 -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(mm, x) do { } while (0)
#define __pud_free_tlb(tlb, x, a) do { } while (0)
#undef pud_addr_end
#define pud_addr_end(addr, end) (end)
#endif /* __ASSEMBLY__ */
#endif /* _PGTABLE_NOPUD_H */