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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)
#if CONFIG_X86_PAE
# include <asm/pgalloc-3level.h>
#else
# include <asm/pgalloc-2level.h>
#endif
/*
* Allocate and free page tables. The xxx_kernel() versions are
* used to allocate a kernel page table - this turns on ASN bits
* if any.
*/
extern __inline__ pgd_t *get_pgd_slow(void)
{
pgd_t *ret = (pgd_t *)__get_free_page(GFP_KERNEL);
if (ret) {
#if CONFIG_X86_PAE
int i;
for (i = 0; i < USER_PTRS_PER_PGD; i++)
__pgd_clear(ret + i);
#else
memset(ret, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
#endif
memcpy(ret + USER_PTRS_PER_PGD, swapper_pg_dir + USER_PTRS_PER_PGD, (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
}
return ret;
}
extern __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;
}
extern __inline__ void free_pgd_fast(pgd_t *pgd)
{
*(unsigned long *)pgd = (unsigned long) pgd_quicklist;
pgd_quicklist = (unsigned long *) pgd;
pgtable_cache_size++;
}
extern __inline__ void free_pgd_slow(pgd_t *pgd)
{
free_page((unsigned long)pgd);
}
extern pte_t *get_pte_slow(pmd_t *pmd, unsigned long address_preadjusted);
extern pte_t *get_pte_kernel_slow(pmd_t *pmd, unsigned long address_preadjusted);
extern __inline__ pte_t *get_pte_fast(void)
{
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;
}
extern __inline__ void free_pte_fast(pte_t *pte)
{
*(unsigned long *)pte = (unsigned long) pte_quicklist;
pte_quicklist = (unsigned long *) pte;
pgtable_cache_size++;
}
extern __inline__ void free_pte_slow(pte_t *pte)
{
free_page((unsigned long)pte);
}
#define pte_free_kernel(pte) free_pte_slow(pte)
#define pte_free(pte) free_pte_slow(pte)
#define pgd_free(pgd) free_pgd_slow(pgd)
#define pgd_alloc() get_pgd_fast()
extern inline pte_t * pte_alloc_kernel(pmd_t * pmd, unsigned long address)
{
if (!pmd)
BUG();
address = (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
if (pmd_none(*pmd)) {
pte_t * page = (pte_t *) get_pte_fast();
if (!page)
return get_pte_kernel_slow(pmd, address);
set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(page)));
return page + address;
}
if (pmd_bad(*pmd)) {
__handle_bad_pmd_kernel(pmd);
return NULL;
}
return (pte_t *) pmd_page(*pmd) + address;
}
extern inline pte_t * pte_alloc(pmd_t * pmd, unsigned long address)
{
address = (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
if (pmd_none(*pmd))
goto getnew;
if (pmd_bad(*pmd))
goto fix;
return (pte_t *)pmd_page(*pmd) + address;
getnew:
{
unsigned long page = (unsigned long) get_pte_fast();
if (!page)
return get_pte_slow(pmd, address);
set_pmd(pmd, __pmd(_PAGE_TABLE + __pa(page)));
return (pte_t *)page + address;
}
fix:
__handle_bad_pmd(pmd);
return NULL;
}
/*
* 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 page.)
*/
#define pmd_free(pmd) free_pmd_slow(pmd)
#define pmd_free_kernel pmd_free
#define pmd_alloc_kernel pmd_alloc
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
extern 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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