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/*
* BK Id: SCCS/s.pgalloc.h 1.9 05/17/01 18:14:25 cort
*/
#ifdef __KERNEL__
#ifndef _PPC_PGALLOC_H
#define _PPC_PGALLOC_H
#include <linux/config.h>
#include <linux/threads.h>
#include <asm/processor.h>
/*
* This is handled very differently on the PPC since out page tables
* are all 0's and I want to be able to use these zero'd pages elsewhere
* as well - it gives us quite a speedup.
*
* Note that the SMP/UP versions are the same but we don't need a
* per cpu list of zero pages because we do the zero-ing with the cache
* off and the access routines are lock-free but the pgt cache stuff
* is per-cpu since it isn't done with any lock-free access routines
* (although I think we need arch-specific routines so I can do lock-free).
*
* I need to generalize this so we can use it for other arch's as well.
* -- Cort
*/
#ifdef CONFIG_SMP
#define quicklists cpu_data[smp_processor_id()]
#else
extern struct pgtable_cache_struct {
unsigned long *pgd_cache;
unsigned long *pte_cache;
unsigned long pgtable_cache_sz;
} quicklists;
#endif
#define pgd_quicklist (quicklists.pgd_cache)
#define pmd_quicklist ((unsigned long *)0)
#define pte_quicklist (quicklists.pte_cache)
#define pgtable_cache_size (quicklists.pgtable_cache_sz)
extern unsigned long *zero_cache; /* head linked list of pre-zero'd pages */
extern atomic_t zero_sz; /* # currently pre-zero'd pages */
extern atomic_t zeropage_hits; /* # zero'd pages request that we've done */
extern atomic_t zeropage_calls; /* # zero'd pages request that've been made */
extern atomic_t zerototal; /* # pages zero'd over time */
#define zero_quicklist (zero_cache)
#define zero_cache_sz (zero_sz)
#define zero_cache_calls (zeropage_calls)
#define zero_cache_hits (zeropage_hits)
#define zero_cache_total (zerototal)
/* return a pre-zero'd page from the list, return NULL if none available -- Cort */
extern unsigned long get_zero_page_fast(void);
extern void __bad_pte(pmd_t *pmd);
extern __inline__ pgd_t *get_pgd_slow(void)
{
pgd_t *ret;
if ((ret = (pgd_t *)__get_free_page(GFP_KERNEL)) != NULL)
clear_page(ret);
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 = pgd_quicklist;
pgd_quicklist = (unsigned long *) pgd;
pgtable_cache_size++;
}
extern __inline__ void free_pgd_slow(pgd_t *pgd)
{
free_page((unsigned long)pgd);
}
#define pgd_free(pgd) free_pgd_fast(pgd)
#define pgd_alloc(mm) get_pgd_fast()
/*
* We don't have any real pmd's, and this code never triggers because
* the pgd will always be present..
*/
#define pmd_alloc_one_fast(mm, address) ({ BUG(); ((pmd_t *)1); })
#define pmd_alloc_one(mm,address) ({ BUG(); ((pmd_t *)2); })
#define pmd_free(x) do { } while (0)
#define pgd_populate(mm, pmd, pte) BUG()
static inline pte_t *pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
pte_t *pte;
extern int mem_init_done;
extern void *early_get_page(void);
if (mem_init_done)
pte = (pte_t *) __get_free_page(GFP_KERNEL);
else
pte = (pte_t *) early_get_page();
if (pte != NULL)
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 = pte_quicklist) != NULL) {
pte_quicklist = (unsigned long *)(*ret);
ret[0] = 0;
pgtable_cache_size--;
}
return (pte_t *)ret;
}
extern __inline__ void pte_free_fast(pte_t *pte)
{
*(unsigned long **)pte = pte_quicklist;
pte_quicklist = (unsigned long *) pte;
pgtable_cache_size++;
}
extern __inline__ void pte_free_slow(pte_t *pte)
{
free_page((unsigned long)pte);
}
#define pte_free(pte) pte_free_slow(pte)
#define pmd_populate(mm, pmd, pte) (pmd_val(*(pmd)) = (unsigned long) (pte))
extern int do_check_pgt_cache(int, int);
#endif /* _PPC_PGALLOC_H */
#endif /* __KERNEL__ */
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