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#ifndef _X86_64_PGALLOC_H
#define _X86_64_PGALLOC_H
#include <asm/fixmap.h>
#include <asm/pda.h>
#include <linux/threads.h>
#include <linux/mm.h>
#define pmd_populate_kernel(mm, pmd, pte) \
set_pmd(pmd, __pmd(_PAGE_TABLE | __pa(pte)))
#define pud_populate(mm, pud, pmd) \
set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)))
#define pgd_populate(mm, pgd, pud) \
set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(pud)))
static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, struct page *pte)
{
set_pmd(pmd, __pmd(_PAGE_TABLE | (page_to_pfn(pte) << PAGE_SHIFT)));
}
static inline pmd_t *get_pmd(void)
{
return (pmd_t *)get_zeroed_page(GFP_KERNEL);
}
static inline void pmd_free(pmd_t *pmd)
{
BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
free_page((unsigned long)pmd);
}
static inline pmd_t *pmd_alloc_one (struct mm_struct *mm, unsigned long addr)
{
return (pmd_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
}
static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
{
return (pud_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
}
static inline void pud_free (pud_t *pud)
{
BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
free_page((unsigned long)pud);
}
static inline void pgd_list_add(pgd_t *pgd)
{
struct page *page = virt_to_page(pgd);
spin_lock(&pgd_lock);
page->index = (pgoff_t)pgd_list;
if (pgd_list)
pgd_list->private = (unsigned long)&page->index;
pgd_list = page;
page->private = (unsigned long)&pgd_list;
spin_unlock(&pgd_lock);
}
static inline void pgd_list_del(pgd_t *pgd)
{
struct page *next, **pprev, *page = virt_to_page(pgd);
spin_lock(&pgd_lock);
next = (struct page *)page->index;
pprev = (struct page **)page->private;
*pprev = next;
if (next)
next->private = (unsigned long)pprev;
spin_unlock(&pgd_lock);
}
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
unsigned boundary;
pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
if (!pgd)
return NULL;
pgd_list_add(pgd);
/*
* Copy kernel pointers in from init.
* Could keep a freelist or slab cache of those because the kernel
* part never changes.
*/
boundary = pgd_index(__PAGE_OFFSET);
memset(pgd, 0, boundary * sizeof(pgd_t));
memcpy(pgd + boundary,
init_level4_pgt + boundary,
(PTRS_PER_PGD - boundary) * sizeof(pgd_t));
return pgd;
}
static inline void pgd_free(pgd_t *pgd)
{
BUG_ON((unsigned long)pgd & (PAGE_SIZE-1));
pgd_list_del(pgd);
free_page((unsigned long)pgd);
}
static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
{
return (pte_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
}
static inline struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
void *p = (void *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
if (!p)
return NULL;
return virt_to_page(p);
}
/* Should really implement gc for free page table pages. This could be
done with a reference count in struct page. */
static inline void pte_free_kernel(pte_t *pte)
{
BUG_ON((unsigned long)pte & (PAGE_SIZE-1));
free_page((unsigned long)pte);
}
static inline void pte_free(struct page *pte)
{
__free_page(pte);
}
#define __pte_free_tlb(tlb,pte) tlb_remove_page((tlb),(pte))
#define __pmd_free_tlb(tlb,x) tlb_remove_page((tlb),virt_to_page(x))
#define __pud_free_tlb(tlb,x) tlb_remove_page((tlb),virt_to_page(x))
#endif /* _X86_64_PGALLOC_H */
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