diff options
Diffstat (limited to 'kernel/arch/x86/mm/hugetlbpage.c')
| -rw-r--r-- | kernel/arch/x86/mm/hugetlbpage.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/kernel/arch/x86/mm/hugetlbpage.c b/kernel/arch/x86/mm/hugetlbpage.c new file mode 100644 index 000000000..42982b26e --- /dev/null +++ b/kernel/arch/x86/mm/hugetlbpage.c @@ -0,0 +1,186 @@ +/* + * IA-32 Huge TLB Page Support for Kernel. + * + * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com> + */ + +#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> + +#if 0 /* This is just for testing */ +struct page * +follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) +{ + unsigned long start = address; + int length = 1; + int nr; + struct page *page; + struct vm_area_struct *vma; + + vma = find_vma(mm, addr); + if (!vma || !is_vm_hugetlb_page(vma)) + return ERR_PTR(-EINVAL); + + pte = huge_pte_offset(mm, address); + + /* hugetlb should be locked, and hence, prefaulted */ + WARN_ON(!pte || pte_none(*pte)); + + page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)]; + + WARN_ON(!PageHead(page)); + + return page; +} + +int pmd_huge(pmd_t pmd) +{ + return 0; +} + +int pud_huge(pud_t pud) +{ + return 0; +} + +#else + +/* + * pmd_huge() returns 1 if @pmd is hugetlb related entry, that is normal + * hugetlb entry or non-present (migration or hwpoisoned) hugetlb entry. + * Otherwise, returns 0. + */ +int pmd_huge(pmd_t pmd) +{ + return !pmd_none(pmd) && + (pmd_val(pmd) & (_PAGE_PRESENT|_PAGE_PSE)) != _PAGE_PRESENT; +} + +int pud_huge(pud_t pud) +{ + return !!(pud_val(pud) & _PAGE_PSE); +} +#endif + +#ifdef CONFIG_HUGETLB_PAGE +static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file, + unsigned long addr, unsigned long len, + unsigned long pgoff, unsigned long flags) +{ + struct hstate *h = hstate_file(file); + struct vm_unmapped_area_info info; + + info.flags = 0; + info.length = len; + info.low_limit = current->mm->mmap_legacy_base; + info.high_limit = TASK_SIZE; + info.align_mask = PAGE_MASK & ~huge_page_mask(h); + info.align_offset = 0; + return vm_unmapped_area(&info); +} + +static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, + unsigned long addr0, unsigned long len, + unsigned long pgoff, unsigned long flags) +{ + struct hstate *h = hstate_file(file); + struct vm_unmapped_area_info info; + unsigned long addr; + + info.flags = VM_UNMAPPED_AREA_TOPDOWN; + info.length = len; + info.low_limit = PAGE_SIZE; + info.high_limit = current->mm->mmap_base; + info.align_mask = PAGE_MASK & ~huge_page_mask(h); + info.align_offset = 0; + addr = vm_unmapped_area(&info); + + /* + * A failed mmap() very likely causes application failure, + * so fall back to the bottom-up function here. This scenario + * can happen with large stack limits and large mmap() + * allocations. + */ + if (addr & ~PAGE_MASK) { + VM_BUG_ON(addr != -ENOMEM); + info.flags = 0; + info.low_limit = TASK_UNMAPPED_BASE; + info.high_limit = TASK_SIZE; + addr = vm_unmapped_area(&info); + } + + return addr; +} + +unsigned long +hugetlb_get_unmapped_area(struct file *file, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + struct hstate *h = hstate_file(file); + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + + if (len & ~huge_page_mask(h)) + return -EINVAL; + if (len > TASK_SIZE) + return -ENOMEM; + + if (flags & MAP_FIXED) { + if (prepare_hugepage_range(file, addr, len)) + return -EINVAL; + return addr; + } + + if (addr) { + addr = ALIGN(addr, huge_page_size(h)); + vma = find_vma(mm, addr); + if (TASK_SIZE - len >= addr && + (!vma || addr + len <= vma->vm_start)) + return addr; + } + if (mm->get_unmapped_area == arch_get_unmapped_area) + return hugetlb_get_unmapped_area_bottomup(file, addr, len, + pgoff, flags); + else + return hugetlb_get_unmapped_area_topdown(file, addr, len, + pgoff, flags); +} +#endif /* CONFIG_HUGETLB_PAGE */ + +#ifdef CONFIG_X86_64 +static __init int setup_hugepagesz(char *opt) +{ + unsigned long ps = memparse(opt, &opt); + if (ps == PMD_SIZE) { + hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT); + } else if (ps == PUD_SIZE && cpu_has_gbpages) { + hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT); + } else { + printk(KERN_ERR "hugepagesz: Unsupported page size %lu M\n", + ps >> 20); + return 0; + } + return 1; +} +__setup("hugepagesz=", setup_hugepagesz); + +#ifdef CONFIG_CMA +static __init int gigantic_pages_init(void) +{ + /* With CMA we can allocate gigantic pages at runtime */ + if (cpu_has_gbpages && !size_to_hstate(1UL << PUD_SHIFT)) + hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT); + return 0; +} +arch_initcall(gigantic_pages_init); +#endif +#endif |