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#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 void set_pgdir(unsigned long address, pgd_t entry)
{
struct task_struct * p;
pgd_t *pgd;
#ifdef CONFIG_SMP
int i;
#endif
read_lock(&tasklist_lock);
for_each_task(p) {
if (!p->mm)
continue;
*pgd_offset(p->mm,address) = entry;
}
read_unlock(&tasklist_lock);
#ifndef CONFIG_SMP
for (pgd = (pgd_t *)pgd_quicklist; pgd; pgd = (pgd_t *)*(unsigned long *)pgd)
pgd[address >> PGDIR_SHIFT] = entry;
#else
/* To pgd_alloc/pgd_free, one holds master kernel lock and so does our callee, so we can
modify pgd caches of other CPUs as well. -jj */
for (i = 0; i < NR_CPUS; i++)
for (pgd = (pgd_t *)cpu_data[i].pgd_cache; pgd; pgd = (pgd_t *)*(unsigned long *)pgd)
pgd[address >> PGDIR_SHIFT] = entry;
#endif
}
/* We don't use pmd cache, so this is a dummy routine */
extern __inline__ pmd_t *get_pmd_fast(void)
{
return (pmd_t *)0;
}
extern __inline__ void free_pmd_fast(pmd_t *pmd)
{
}
extern __inline__ void free_pmd_slow(pmd_t *pmd)
{
}
/*
* allocating and freeing a pmd is trivial: the 1-entry pmd is
* inside the pgd, so has no extra memory associated with it.
*/
extern inline void pmd_free(pmd_t * pmd)
{
}
extern inline pmd_t * pmd_alloc(pgd_t * pgd, unsigned long address)
{
return (pmd_t *) pgd;
}
#define pmd_free_kernel pmd_free
#define pmd_alloc_kernel pmd_alloc
#define pte_alloc_kernel pte_alloc
extern __inline__ pgd_t *get_pgd_slow(void)
{
pgd_t *ret, *init;
/*if ( (ret = (pgd_t *)get_zero_page_fast()) == NULL )*/
if ( (ret = (pgd_t *)__get_free_page(GFP_KERNEL)) != NULL )
memset (ret, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
if (ret) {
init = pgd_offset(&init_mm, 0);
memcpy (ret + USER_PTRS_PER_PGD, init + 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 = 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 __inline__ pte_t *get_pte_fast(void)
{
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 free_pte_fast(pte_t *pte)
{
*(unsigned long **)pte = 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_fast(pte)
#define pte_free(pte) free_pte_fast(pte)
#define pgd_free(pgd) free_pgd_fast(pgd)
#define pgd_alloc() get_pgd_fast()
extern inline pte_t * pte_alloc(pmd_t * pmd, unsigned long address)
{
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_slow(pmd, address);
pmd_val(*pmd) = (unsigned long) page;
return page + address;
}
if (pmd_bad(*pmd)) {
__bad_pte(pmd);
return NULL;
}
return (pte_t *) pmd_page(*pmd) + address;
}
extern int do_check_pgt_cache(int, int);
#endif /* _PPC_PGALLOC_H */
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