| /* |
| * IA-64 Huge TLB Page Support for Kernel. |
| * |
| * Copyright (C) 2002-2004 Rohit Seth <rohit.seth@intel.com> |
| * Copyright (C) 2003-2004 Ken Chen <kenneth.w.chen@intel.com> |
| * |
| * Sep, 2003: add numa support |
| * Feb, 2004: dynamic hugetlb page size via boot parameter |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/init.h> |
| #include <linux/fs.h> |
| #include <linux/mm.h> |
| #include <linux/hugetlb.h> |
| #include <linux/pagemap.h> |
| #include <linux/smp_lock.h> |
| #include <linux/slab.h> |
| #include <linux/sysctl.h> |
| #include <asm/mman.h> |
| #include <asm/pgalloc.h> |
| #include <asm/tlb.h> |
| #include <asm/tlbflush.h> |
| |
| unsigned int hpage_shift=HPAGE_SHIFT_DEFAULT; |
| |
| static pte_t * |
| huge_pte_alloc (struct mm_struct *mm, unsigned long addr) |
| { |
| unsigned long taddr = htlbpage_to_page(addr); |
| pgd_t *pgd; |
| pud_t *pud; |
| pmd_t *pmd; |
| pte_t *pte = NULL; |
| |
| pgd = pgd_offset(mm, taddr); |
| pud = pud_alloc(mm, pgd, taddr); |
| if (pud) { |
| pmd = pmd_alloc(mm, pud, taddr); |
| if (pmd) |
| pte = pte_alloc_map(mm, pmd, taddr); |
| } |
| return pte; |
| } |
| |
| static pte_t * |
| huge_pte_offset (struct mm_struct *mm, unsigned long addr) |
| { |
| unsigned long taddr = htlbpage_to_page(addr); |
| pgd_t *pgd; |
| pud_t *pud; |
| pmd_t *pmd; |
| pte_t *pte = NULL; |
| |
| pgd = pgd_offset(mm, taddr); |
| if (pgd_present(*pgd)) { |
| pud = pud_offset(pgd, taddr); |
| if (pud_present(*pud)) { |
| pmd = pmd_offset(pud, taddr); |
| if (pmd_present(*pmd)) |
| pte = pte_offset_map(pmd, taddr); |
| } |
| } |
| |
| return pte; |
| } |
| |
| #define mk_pte_huge(entry) { pte_val(entry) |= _PAGE_P; } |
| |
| static void |
| set_huge_pte (struct mm_struct *mm, struct vm_area_struct *vma, |
| struct page *page, pte_t * page_table, int write_access) |
| { |
| pte_t entry; |
| |
| add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE); |
| if (write_access) { |
| entry = |
| pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot))); |
| } else |
| entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot)); |
| entry = pte_mkyoung(entry); |
| mk_pte_huge(entry); |
| set_pte(page_table, entry); |
| return; |
| } |
| /* |
| * This function checks for proper alignment of input addr and len parameters. |
| */ |
| int is_aligned_hugepage_range(unsigned long addr, unsigned long len) |
| { |
| if (len & ~HPAGE_MASK) |
| return -EINVAL; |
| if (addr & ~HPAGE_MASK) |
| return -EINVAL; |
| if (REGION_NUMBER(addr) != REGION_HPAGE) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, |
| struct vm_area_struct *vma) |
| { |
| pte_t *src_pte, *dst_pte, entry; |
| struct page *ptepage; |
| unsigned long addr = vma->vm_start; |
| unsigned long end = vma->vm_end; |
| |
| while (addr < end) { |
| dst_pte = huge_pte_alloc(dst, addr); |
| if (!dst_pte) |
| goto nomem; |
| src_pte = huge_pte_offset(src, addr); |
| entry = *src_pte; |
| ptepage = pte_page(entry); |
| get_page(ptepage); |
| set_pte(dst_pte, entry); |
| add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE); |
| addr += HPAGE_SIZE; |
| } |
| return 0; |
| nomem: |
| return -ENOMEM; |
| } |
| |
| int |
| follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, |
| struct page **pages, struct vm_area_struct **vmas, |
| unsigned long *st, int *length, int i) |
| { |
| pte_t *ptep, pte; |
| unsigned long start = *st; |
| unsigned long pstart; |
| int len = *length; |
| struct page *page; |
| |
| do { |
| pstart = start & HPAGE_MASK; |
| ptep = huge_pte_offset(mm, start); |
| pte = *ptep; |
| |
| back1: |
| page = pte_page(pte); |
| if (pages) { |
| page += ((start & ~HPAGE_MASK) >> PAGE_SHIFT); |
| get_page(page); |
| pages[i] = page; |
| } |
| if (vmas) |
| vmas[i] = vma; |
| i++; |
| len--; |
| start += PAGE_SIZE; |
| if (((start & HPAGE_MASK) == pstart) && len && |
| (start < vma->vm_end)) |
| goto back1; |
| } while (len && start < vma->vm_end); |
| *length = len; |
| *st = start; |
| return i; |
| } |
| |
| struct page *follow_huge_addr(struct mm_struct *mm, unsigned long addr, int write) |
| { |
| struct page *page; |
| pte_t *ptep; |
| |
| if (REGION_NUMBER(addr) != REGION_HPAGE) |
| return ERR_PTR(-EINVAL); |
| |
| ptep = huge_pte_offset(mm, addr); |
| if (!ptep || pte_none(*ptep)) |
| return NULL; |
| page = pte_page(*ptep); |
| page += ((addr & ~HPAGE_MASK) >> PAGE_SHIFT); |
| return page; |
| } |
| int pmd_huge(pmd_t pmd) |
| { |
| return 0; |
| } |
| struct page * |
| follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int write) |
| { |
| return NULL; |
| } |
| |
| void hugetlb_free_pgd_range(struct mmu_gather **tlb, |
| unsigned long addr, unsigned long end, |
| unsigned long floor, unsigned long ceiling) |
| { |
| /* |
| * This is called only when is_hugepage_only_range(addr,), |
| * and it follows that is_hugepage_only_range(end,) also. |
| * |
| * The offset of these addresses from the base of the hugetlb |
| * region must be scaled down by HPAGE_SIZE/PAGE_SIZE so that |
| * the standard free_pgd_range will free the right page tables. |
| * |
| * If floor and ceiling are also in the hugetlb region, they |
| * must likewise be scaled down; but if outside, left unchanged. |
| */ |
| |
| addr = htlbpage_to_page(addr); |
| end = htlbpage_to_page(end); |
| if (is_hugepage_only_range(tlb->mm, floor, HPAGE_SIZE)) |
| floor = htlbpage_to_page(floor); |
| if (is_hugepage_only_range(tlb->mm, ceiling, HPAGE_SIZE)) |
| ceiling = htlbpage_to_page(ceiling); |
| |
| free_pgd_range(tlb, addr, end, floor, ceiling); |
| } |
| |
| void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) |
| { |
| struct mm_struct *mm = vma->vm_mm; |
| unsigned long address; |
| pte_t *pte; |
| struct page *page; |
| |
| BUG_ON(start & (HPAGE_SIZE - 1)); |
| BUG_ON(end & (HPAGE_SIZE - 1)); |
| |
| for (address = start; address < end; address += HPAGE_SIZE) { |
| pte = huge_pte_offset(mm, address); |
| if (pte_none(*pte)) |
| continue; |
| page = pte_page(*pte); |
| put_page(page); |
| pte_clear(mm, address, pte); |
| } |
| add_mm_counter(mm, rss, - ((end - start) >> PAGE_SHIFT)); |
| flush_tlb_range(vma, start, end); |
| } |
| |
| int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma) |
| { |
| struct mm_struct *mm = current->mm; |
| unsigned long addr; |
| int ret = 0; |
| |
| BUG_ON(vma->vm_start & ~HPAGE_MASK); |
| BUG_ON(vma->vm_end & ~HPAGE_MASK); |
| |
| spin_lock(&mm->page_table_lock); |
| for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) { |
| unsigned long idx; |
| pte_t *pte = huge_pte_alloc(mm, addr); |
| struct page *page; |
| |
| if (!pte) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| if (!pte_none(*pte)) |
| continue; |
| |
| idx = ((addr - vma->vm_start) >> HPAGE_SHIFT) |
| + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT)); |
| page = find_get_page(mapping, idx); |
| if (!page) { |
| /* charge the fs quota first */ |
| if (hugetlb_get_quota(mapping)) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| page = alloc_huge_page(); |
| if (!page) { |
| hugetlb_put_quota(mapping); |
| ret = -ENOMEM; |
| goto out; |
| } |
| ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC); |
| if (! ret) { |
| unlock_page(page); |
| } else { |
| hugetlb_put_quota(mapping); |
| page_cache_release(page); |
| goto out; |
| } |
| } |
| set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE); |
| } |
| out: |
| spin_unlock(&mm->page_table_lock); |
| return ret; |
| } |
| |
| unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, |
| unsigned long pgoff, unsigned long flags) |
| { |
| struct vm_area_struct *vmm; |
| |
| if (len > RGN_MAP_LIMIT) |
| return -ENOMEM; |
| if (len & ~HPAGE_MASK) |
| return -EINVAL; |
| /* This code assumes that REGION_HPAGE != 0. */ |
| if ((REGION_NUMBER(addr) != REGION_HPAGE) || (addr & (HPAGE_SIZE - 1))) |
| addr = HPAGE_REGION_BASE; |
| else |
| addr = ALIGN(addr, HPAGE_SIZE); |
| for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) { |
| /* At this point: (!vmm || addr < vmm->vm_end). */ |
| if (REGION_OFFSET(addr) + len > RGN_MAP_LIMIT) |
| return -ENOMEM; |
| if (!vmm || (addr + len) <= vmm->vm_start) |
| return addr; |
| addr = ALIGN(vmm->vm_end, HPAGE_SIZE); |
| } |
| } |
| |
| static int __init hugetlb_setup_sz(char *str) |
| { |
| u64 tr_pages; |
| unsigned long long size; |
| |
| if (ia64_pal_vm_page_size(&tr_pages, NULL) != 0) |
| /* |
| * shouldn't happen, but just in case. |
| */ |
| tr_pages = 0x15557000UL; |
| |
| size = memparse(str, &str); |
| if (*str || (size & (size-1)) || !(tr_pages & size) || |
| size <= PAGE_SIZE || |
| size >= (1UL << PAGE_SHIFT << MAX_ORDER)) { |
| printk(KERN_WARNING "Invalid huge page size specified\n"); |
| return 1; |
| } |
| |
| hpage_shift = __ffs(size); |
| /* |
| * boot cpu already executed ia64_mmu_init, and has HPAGE_SHIFT_DEFAULT |
| * override here with new page shift. |
| */ |
| ia64_set_rr(HPAGE_REGION_BASE, hpage_shift << 2); |
| return 1; |
| } |
| __setup("hugepagesz=", hugetlb_setup_sz); |