linux/arch/riscv/include/asm/pgalloc.h
Palmer Dabbelt 07037db5d4 RISC-V: Paging and MMU
This patch contains code to manage the RISC-V MMU, including definitions
of the page tables and the page walking code.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26 15:26:47 -07:00

125 lines
3.1 KiB
C

/*
* Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
* Copyright (C) 2012 Regents of the University of California
*
* 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, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _ASM_RISCV_PGALLOC_H
#define _ASM_RISCV_PGALLOC_H
#include <linux/mm.h>
#include <asm/tlb.h>
static inline void pmd_populate_kernel(struct mm_struct *mm,
pmd_t *pmd, pte_t *pte)
{
unsigned long pfn = virt_to_pfn(pte);
set_pmd(pmd, __pmd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
}
static inline void pmd_populate(struct mm_struct *mm,
pmd_t *pmd, pgtable_t pte)
{
unsigned long pfn = virt_to_pfn(page_address(pte));
set_pmd(pmd, __pmd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
}
#ifndef __PAGETABLE_PMD_FOLDED
static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
{
unsigned long pfn = virt_to_pfn(pmd);
set_pud(pud, __pud((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
}
#endif /* __PAGETABLE_PMD_FOLDED */
#define pmd_pgtable(pmd) pmd_page(pmd)
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd;
pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
if (likely(pgd != NULL)) {
memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
/* Copy kernel mappings */
memcpy(pgd + USER_PTRS_PER_PGD,
init_mm.pgd + USER_PTRS_PER_PGD,
(PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
}
return pgd;
}
static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
free_page((unsigned long)pgd);
}
#ifndef __PAGETABLE_PMD_FOLDED
static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
{
return (pmd_t *)__get_free_page(
GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_ZERO);
}
static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
{
free_page((unsigned long)pmd);
}
#define __pmd_free_tlb(tlb, pmd, addr) pmd_free((tlb)->mm, pmd)
#endif /* __PAGETABLE_PMD_FOLDED */
static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
unsigned long address)
{
return (pte_t *)__get_free_page(
GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_ZERO);
}
static inline struct page *pte_alloc_one(struct mm_struct *mm,
unsigned long address)
{
struct page *pte;
pte = alloc_page(GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_ZERO);
if (likely(pte != NULL))
pgtable_page_ctor(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, pgtable_t pte)
{
pgtable_page_dtor(pte);
__free_page(pte);
}
#define __pte_free_tlb(tlb, pte, buf) \
do { \
pgtable_page_dtor(pte); \
tlb_remove_page((tlb), pte); \
} while (0)
static inline void check_pgt_cache(void)
{
}
#endif /* _ASM_RISCV_PGALLOC_H */