pgalloc.h

Go to the documentation of this file.

/*
 * OpenRISC Linux
 *
 * Linux architectural port borrowing liberally from similar works of
 * others.  All original copyrights apply as per the original source
 * declaration.
 *
 * OpenRISC implementation:
 * Copyright (C) 2003 Matjaz Breskvar <[email protected]>
 * Copyright (C) 2010-2011 Jonas Bonn <[email protected]>
 * et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#ifndef __ASM_OPENRISC_PGALLOC_H
#define __ASM_OPENRISC_PGALLOC_H

#include <asm/page.h>
#include <linux/threads.h>
#include <linux/mm.h>
#include <linux/memblock.h>
#include <linux/bootmem.h>

extern int mem_init_done;

#define pmd_populate_kernel(mm, pmd, pte) \
    set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(pte)))

static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
                struct page *pte)
{
    set_pmd(pmd, __pmd(_KERNPG_TABLE +
             ((unsigned long)page_to_pfn(pte) <<
             (unsigned long) PAGE_SHIFT)));
}

/*
 * Allocate and free page tables.
 */
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
    pgd_t *ret = (pgd_t *)__get_free_page(GFP_KERNEL);

    if (ret) {
        memset(ret, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
        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;
}

#if 0
/* FIXME: This seems to be the preferred style, but we are using
 * current_pgd (from mm->pgd) to load kernel pages so we need it
 * initialized.  This needs to be looked into.
 */
extern inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
    return (pgd_t *)get_zeroed_page(GFP_KERNEL);
}
#endif

static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
    free_page((unsigned long)pgd);
}

extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address);

static inline struct page *pte_alloc_one(struct mm_struct *mm,
                     unsigned long address)
{
    struct page *pte;
    pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0);
    if (pte)
        clear_page(page_address(pte));
    return pte;
}

static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
{
    free_page((unsigned long)pte);
}

static inline void pte_free(struct mm_struct *mm, struct page *pte)
{
    __free_page(pte);
}


#define __pte_free_tlb(tlb, pte, addr) tlb_remove_page((tlb), (pte))
#define pmd_pgtable(pmd) pmd_page(pmd)

#define check_pgt_cache()          do { } while (0)

#endif