#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 */