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#ifndef _I386_PGALLOC_H
#define _I386_PGALLOC_H
#include <linux/config.h>
#include <asm/processor.h>
#include <asm/fixmap.h>
#include <linux/threads.h>
#define pgd_quicklist (current_cpu_data.pgd_quick)
#define pmd_quicklist (current_cpu_data.pmd_quick)
#define pte_quicklist (current_cpu_data.pte_quick)
#define pgtable_cache_size (current_cpu_data.pgtable_cache_sz)
#define pmd_populate(mm, pmd, pte) \
set_pmd(pmd, __pmd(_PAGE_TABLE + __pa(pte)))
/*
* Allocate and free page tables.
*/
#if CONFIG_X86_PAE
extern void *kmalloc(size_t, int);
extern void kfree(const void *);
static __inline__ pgd_t *get_pgd_slow(void)
{
int i;
pgd_t *pgd = kmalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL);
if (pgd) {
for (i = 0; i < USER_PTRS_PER_PGD; i++) {
unsigned long pmd = __get_free_page(GFP_KERNEL);
if (!pmd)
goto out_oom;
clear_page(pmd);
set_pgd(pgd + i, __pgd(1 + __pa(pmd)));
}
memcpy(pgd + USER_PTRS_PER_PGD, swapper_pg_dir + USER_PTRS_PER_PGD, (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
}
return pgd;
out_oom:
for (i--; i >= 0; i--)
free_page((unsigned long)__va(pgd_val(pgd[i])-1));
kfree(pgd);
return NULL;
}
#else
static __inline__ pgd_t *get_pgd_slow(void)
{
pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
if (pgd) {
memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
memcpy(pgd + USER_PTRS_PER_PGD, swapper_pg_dir + USER_PTRS_PER_PGD, (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
}
return pgd;
}
#endif
static __inline__ pgd_t *get_pgd_fast(void)
{
unsigned long *ret;
if ((ret = pgd_quicklist) != NULL) {
pgd_quicklist = (unsigned long *)(*ret);
ret[0] = 0;
pgtable_cache_size--;
} else
ret = (unsigned long *)get_pgd_slow();
return (pgd_t *)ret;
}
static __inline__ void free_pgd_fast(pgd_t *pgd)
{
*(unsigned long *)pgd = (unsigned long) pgd_quicklist;
pgd_quicklist = (unsigned long *) pgd;
pgtable_cache_size++;
}
static __inline__ void free_pgd_slow(pgd_t *pgd)
{
#if CONFIG_X86_PAE
int i;
for (i = 0; i < USER_PTRS_PER_PGD; i++)
free_page((unsigned long)__va(pgd_val(pgd[i])-1));
kfree(pgd);
#else
free_page((unsigned long)pgd);
#endif
}
static inline pte_t *pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
pte_t *pte;
pte = (pte_t *) __get_free_page(GFP_KERNEL);
if (pte)
clear_page(pte);
return pte;
}
static inline pte_t *pte_alloc_one_fast(struct mm_struct *mm, unsigned long address)
{
unsigned long *ret;
if ((ret = (unsigned long *)pte_quicklist) != NULL) {
pte_quicklist = (unsigned long *)(*ret);
ret[0] = ret[1];
pgtable_cache_size--;
}
return (pte_t *)ret;
}
static __inline__ void pte_free_fast(pte_t *pte)
{
*(unsigned long *)pte = (unsigned long) pte_quicklist;
pte_quicklist = (unsigned long *) pte;
pgtable_cache_size++;
}
static __inline__ void pte_free_slow(pte_t *pte)
{
free_page((unsigned long)pte);
}
#define pte_free(pte) pte_free_fast(pte)
#ifdef CONFIG_X86_PAE
#define pgd_alloc(mm) get_pgd_slow()
#define pgd_free(pgd) free_pgd_slow(pgd)
#else
#define pgd_alloc(mm) get_pgd_fast()
#define pgd_free(pgd) free_pgd_fast(pgd)
#endif
/*
* allocating and freeing a pmd is trivial: the 1-entry pmd is
* inside the pgd, so has no extra memory associated with it.
* (In the PAE case we free the pmds as part of the pgd.)
*/
#define pmd_alloc_one_fast(mm, addr) ({ BUG(); ((pmd_t *)1); })
#define pmd_alloc_one(mm, addr) ({ BUG(); ((pmd_t *)2); })
#define pmd_free_slow(x) do { } while (0)
#define pmd_free_fast(x) do { } while (0)
#define pmd_free(x) do { } while (0)
#define pgd_populate(mm, pmd, pte) BUG()
extern int do_check_pgt_cache(int, int);
/*
* TLB flushing:
*
* - flush_tlb() flushes the current mm struct TLBs
* - flush_tlb_all() flushes all processes TLBs
* - flush_tlb_mm(mm) flushes the specified mm context TLB's
* - flush_tlb_page(vma, vmaddr) flushes one page
* - flush_tlb_range(mm, start, end) flushes a range of pages
* - flush_tlb_pgtables(mm, start, end) flushes a range of page tables
*
* ..but the i386 has somewhat limited tlb flushing capabilities,
* and page-granular flushes are available only on i486 and up.
*/
#ifndef CONFIG_SMP
#define flush_tlb() __flush_tlb()
#define flush_tlb_all() __flush_tlb_all()
#define local_flush_tlb() __flush_tlb()
static inline void flush_tlb_mm(struct mm_struct *mm)
{
if (mm == current->active_mm)
__flush_tlb();
}
static inline void flush_tlb_page(struct vm_area_struct *vma,
unsigned long addr)
{
if (vma->vm_mm == current->active_mm)
__flush_tlb_one(addr);
}
static inline void flush_tlb_range(struct mm_struct *mm,
unsigned long start, unsigned long end)
{
if (mm == current->active_mm)
__flush_tlb();
}
#else
#include <asm/smp.h>
#define local_flush_tlb() \
__flush_tlb()
extern void flush_tlb_all(void);
extern void flush_tlb_current_task(void);
extern void flush_tlb_mm(struct mm_struct *);
extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
#define flush_tlb() flush_tlb_current_task()
static inline void flush_tlb_range(struct mm_struct * mm, unsigned long start, unsigned long end)
{
flush_tlb_mm(mm);
}
#define TLBSTATE_OK 1
#define TLBSTATE_LAZY 2
struct tlb_state
{
struct mm_struct *active_mm;
int state;
};
extern struct tlb_state cpu_tlbstate[NR_CPUS];
#endif
static inline void flush_tlb_pgtables(struct mm_struct *mm,
unsigned long start, unsigned long end)
{
/* i386 does not keep any page table caches in TLB */
}
#endif /* _I386_PGALLOC_H */
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