diff options
Diffstat (limited to 'arch/arm/mm/hugetlbpage-2level.c')
| -rw-r--r-- | arch/arm/mm/hugetlbpage-2level.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/arch/arm/mm/hugetlbpage-2level.c b/arch/arm/mm/hugetlbpage-2level.c new file mode 100644 index 00000000000..4b2b38ca0f4 --- /dev/null +++ b/arch/arm/mm/hugetlbpage-2level.c @@ -0,0 +1,115 @@ +/* + * arch/arm/mm/hugetlbpage-2level.c + * + * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com> + * Copyright (C) 2012 ARM Ltd + * Copyright (C) 2012 Bill Carson. + * + * Based on arch/x86/include/asm/hugetlb.h and Bill Carson's patches + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/init.h> +#include <linux/fs.h> +#include <linux/mm.h> +#include <linux/hugetlb.h> +#include <linux/pagemap.h> +#include <linux/err.h> +#include <linux/sysctl.h> +#include <asm/mman.h> +#include <asm/tlb.h> +#include <asm/tlbflush.h> +#include <asm/pgalloc.h> + +int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) +{ + return 0; +} + +pte_t *huge_pte_alloc(struct mm_struct *mm, + unsigned long addr, unsigned long sz) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + + pgd = pgd_offset(mm, addr); + pud = pud_offset(pgd, addr); + pmd = pmd_offset(pud, addr); + + return (pte_t *)pmd; /* our huge pte is actually a pmd */ +} + +struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address, + pmd_t *pmd, int write) +{ + struct page *page; + unsigned long pfn; + + BUG_ON((pmd_val(*pmd) & PMD_TYPE_MASK) != PMD_TYPE_SECT); + pfn = ((pmd_val(*pmd) & HPAGE_MASK) >> PAGE_SHIFT); + page = pfn_to_page(pfn); + return page; +} + +pte_t huge_ptep_get(pte_t *ptep) +{ + pmd_t *pmdp = (pmd_t*)ptep; + pmdval_t pmdval = pmd_val(*pmdp); + pteval_t retval; + + if (!pmdval) + return __pte(0); + + retval = (pteval_t) (pmdval & HPAGE_MASK); + HPMD_XLATE(retval, pmdval, PMD_SECT_XN, L_PTE_XN); + HPMD_XLATE(retval, pmdval, PMD_SECT_S, L_PTE_SHARED); + HPMD_XLATE(retval, pmdval, PMD_DSECT_AF, L_PTE_YOUNG); + HPMD_XLATE(retval, pmdval, PMD_DSECT_DIRTY, L_PTE_DIRTY); + + /* preserve bits C & B */ + retval |= (pmdval & (3 << 2)); + + /* PMD TEX bit 0 corresponds to Linux PTE bit 4 */ + HPMD_XLATE(retval, pmdval, PMD_SECT_TEX(1), 1 << 4); + + if (pmdval & PMD_SECT_AP_WRITE) + retval &= ~L_PTE_RDONLY; + else + retval |= L_PTE_RDONLY; + + if ((pmdval & PMD_TYPE_MASK) == PMD_TYPE_SECT) + retval |= L_PTE_VALID; + + /* we assume all hugetlb pages are user */ + retval |= L_PTE_USER; + + return __pte(retval); +} + +void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + pmdval_t pmdval = (pmdval_t) pte_val(pte); + pmd_t *pmdp = (pmd_t*) ptep; + + pmdval &= HPAGE_MASK; + pmdval |= PMD_SECT_AP_READ | PMD_SECT_nG | PMD_TYPE_SECT; + pmdval = pmd_val(pmd_modify(__pmd(pmdval), __pgprot(pte_val(pte)))); + + __sync_icache_dcache(pte); + + set_pmd_at(mm, addr, pmdp, __pmd(pmdval)); +} |