linux-stable/arch/powerpc/include/asm/pgalloc-64.h
David Gibson d28513bc7f powerpc/mm: Fix pgtable cache cleanup with CONFIG_PPC_SUBPAGE_PROT
Commit a0668cdc15 cleans up the handling
of kmem_caches for allocating various levels of pagetables.
Unfortunately, it conflicts badly with CONFIG_PPC_SUBPAGE_PROT, due to
the latter's cleverly hidden technique of adding some extra allocation
space to the top level page directory to store the extra information
it needs.

Since that extra allocation really doesn't fit into the cleaned up
page directory allocating scheme, this patch alters
CONFIG_PPC_SUBPAGE_PROT to instead allocate its struct
subpage_prot_table as part of the mm_context_t.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-08 15:59:33 +11:00

137 lines
3.9 KiB
C

#ifndef _ASM_POWERPC_PGALLOC_64_H
#define _ASM_POWERPC_PGALLOC_64_H
/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/slab.h>
#include <linux/cpumask.h>
#include <linux/percpu.h>
/*
* Functions that deal with pagetables that could be at any level of
* the table need to be passed an "index_size" so they know how to
* handle allocation. For PTE pages (which are linked to a struct
* page for now, and drawn from the main get_free_pages() pool), the
* allocation size will be (2^index_size * sizeof(pointer)) and
* allocations are drawn from the kmem_cache in PGT_CACHE(index_size).
*
* The maximum index size needs to be big enough to allow any
* pagetable sizes we need, but small enough to fit in the low bits of
* any page table pointer. In other words all pagetables, even tiny
* ones, must be aligned to allow at least enough low 0 bits to
* contain this value. This value is also used as a mask, so it must
* be one less than a power of two.
*/
#define MAX_PGTABLE_INDEX_SIZE 0xf
extern struct kmem_cache *pgtable_cache[];
#define PGT_CACHE(shift) (pgtable_cache[(shift)-1])
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE), GFP_KERNEL);
}
static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
}
#ifndef CONFIG_PPC_64K_PAGES
#define pgd_populate(MM, PGD, PUD) pgd_set(PGD, PUD)
static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
{
return kmem_cache_alloc(PGT_CACHE(PUD_INDEX_SIZE),
GFP_KERNEL|__GFP_REPEAT);
}
static inline void pud_free(struct mm_struct *mm, pud_t *pud)
{
kmem_cache_free(PGT_CACHE(PUD_INDEX_SIZE), pud);
}
static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
{
pud_set(pud, (unsigned long)pmd);
}
#define pmd_populate(mm, pmd, pte_page) \
pmd_populate_kernel(mm, pmd, page_address(pte_page))
#define pmd_populate_kernel(mm, pmd, pte) pmd_set(pmd, (unsigned long)(pte))
#define pmd_pgtable(pmd) pmd_page(pmd)
#else /* CONFIG_PPC_64K_PAGES */
#define pud_populate(mm, pud, pmd) pud_set(pud, (unsigned long)pmd)
static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
pte_t *pte)
{
pmd_set(pmd, (unsigned long)pte);
}
#define pmd_populate(mm, pmd, pte_page) \
pmd_populate_kernel(mm, pmd, page_address(pte_page))
#define pmd_pgtable(pmd) pmd_page(pmd)
#endif /* CONFIG_PPC_64K_PAGES */
static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
{
return kmem_cache_alloc(PGT_CACHE(PMD_INDEX_SIZE),
GFP_KERNEL|__GFP_REPEAT);
}
static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
{
kmem_cache_free(PGT_CACHE(PMD_INDEX_SIZE), pmd);
}
static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
unsigned long address)
{
return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO);
}
static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
unsigned long address)
{
struct page *page;
pte_t *pte;
pte = pte_alloc_one_kernel(mm, address);
if (!pte)
return NULL;
page = virt_to_page(pte);
pgtable_page_ctor(page);
return page;
}
static inline void pgtable_free(void *table, unsigned index_size)
{
if (!index_size)
free_page((unsigned long)table);
else {
BUG_ON(index_size > MAX_PGTABLE_INDEX_SIZE);
kmem_cache_free(PGT_CACHE(index_size), table);
}
}
#define __pmd_free_tlb(tlb, pmd, addr) \
pgtable_free_tlb(tlb, pmd, PMD_INDEX_SIZE)
#ifndef CONFIG_PPC_64K_PAGES
#define __pud_free_tlb(tlb, pud, addr) \
pgtable_free_tlb(tlb, pud, PUD_INDEX_SIZE)
#endif /* CONFIG_PPC_64K_PAGES */
#define check_pgt_cache() do { } while (0)
#endif /* _ASM_POWERPC_PGALLOC_64_H */