1 /* 2 * IA-64 Huge TLB Page Support for Kernel. 3 * 4 * Copyright (C) 2002-2004 Rohit Seth <rohit.seth@intel.com> 5 * Copyright (C) 2003-2004 Ken Chen <kenneth.w.chen@intel.com> 6 * 7 * Sep, 2003: add numa support 8 * Feb, 2004: dynamic hugetlb page size via boot parameter 9 */ 10 11 #include <linux/config.h> 12 #include <linux/init.h> 13 #include <linux/fs.h> 14 #include <linux/mm.h> 15 #include <linux/hugetlb.h> 16 #include <linux/pagemap.h> 17 #include <linux/smp_lock.h> 18 #include <linux/slab.h> 19 #include <linux/sysctl.h> 20 #include <asm/mman.h> 21 #include <asm/pgalloc.h> 22 #include <asm/tlb.h> 23 #include <asm/tlbflush.h> 24 25 unsigned int hpage_shift=HPAGE_SHIFT_DEFAULT; 26 27 pte_t * 28 huge_pte_alloc (struct mm_struct *mm, unsigned long addr) 29 { 30 unsigned long taddr = htlbpage_to_page(addr); 31 pgd_t *pgd; 32 pud_t *pud; 33 pmd_t *pmd; 34 pte_t *pte = NULL; 35 36 pgd = pgd_offset(mm, taddr); 37 pud = pud_alloc(mm, pgd, taddr); 38 if (pud) { 39 pmd = pmd_alloc(mm, pud, taddr); 40 if (pmd) 41 pte = pte_alloc_map(mm, pmd, taddr); 42 } 43 return pte; 44 } 45 46 pte_t * 47 huge_pte_offset (struct mm_struct *mm, unsigned long addr) 48 { 49 unsigned long taddr = htlbpage_to_page(addr); 50 pgd_t *pgd; 51 pud_t *pud; 52 pmd_t *pmd; 53 pte_t *pte = NULL; 54 55 pgd = pgd_offset(mm, taddr); 56 if (pgd_present(*pgd)) { 57 pud = pud_offset(pgd, taddr); 58 if (pud_present(*pud)) { 59 pmd = pmd_offset(pud, taddr); 60 if (pmd_present(*pmd)) 61 pte = pte_offset_map(pmd, taddr); 62 } 63 } 64 65 return pte; 66 } 67 68 #define mk_pte_huge(entry) { pte_val(entry) |= _PAGE_P; } 69 70 /* 71 * This function checks for proper alignment of input addr and len parameters. 72 */ 73 int is_aligned_hugepage_range(unsigned long addr, unsigned long len) 74 { 75 if (len & ~HPAGE_MASK) 76 return -EINVAL; 77 if (addr & ~HPAGE_MASK) 78 return -EINVAL; 79 if (REGION_NUMBER(addr) != RGN_HPAGE) 80 return -EINVAL; 81 82 return 0; 83 } 84 85 struct page *follow_huge_addr(struct mm_struct *mm, unsigned long addr, int write) 86 { 87 struct page *page; 88 pte_t *ptep; 89 90 if (REGION_NUMBER(addr) != RGN_HPAGE) 91 return ERR_PTR(-EINVAL); 92 93 ptep = huge_pte_offset(mm, addr); 94 if (!ptep || pte_none(*ptep)) 95 return NULL; 96 page = pte_page(*ptep); 97 page += ((addr & ~HPAGE_MASK) >> PAGE_SHIFT); 98 return page; 99 } 100 int pmd_huge(pmd_t pmd) 101 { 102 return 0; 103 } 104 struct page * 105 follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int write) 106 { 107 return NULL; 108 } 109 110 void hugetlb_free_pgd_range(struct mmu_gather **tlb, 111 unsigned long addr, unsigned long end, 112 unsigned long floor, unsigned long ceiling) 113 { 114 /* 115 * This is called only when is_hugepage_only_range(addr,), 116 * and it follows that is_hugepage_only_range(end,) also. 117 * 118 * The offset of these addresses from the base of the hugetlb 119 * region must be scaled down by HPAGE_SIZE/PAGE_SIZE so that 120 * the standard free_pgd_range will free the right page tables. 121 * 122 * If floor and ceiling are also in the hugetlb region, they 123 * must likewise be scaled down; but if outside, left unchanged. 124 */ 125 126 addr = htlbpage_to_page(addr); 127 end = htlbpage_to_page(end); 128 if (is_hugepage_only_range(tlb->mm, floor, HPAGE_SIZE)) 129 floor = htlbpage_to_page(floor); 130 if (is_hugepage_only_range(tlb->mm, ceiling, HPAGE_SIZE)) 131 ceiling = htlbpage_to_page(ceiling); 132 133 free_pgd_range(tlb, addr, end, floor, ceiling); 134 } 135 136 unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, 137 unsigned long pgoff, unsigned long flags) 138 { 139 struct vm_area_struct *vmm; 140 141 if (len > RGN_MAP_LIMIT) 142 return -ENOMEM; 143 if (len & ~HPAGE_MASK) 144 return -EINVAL; 145 /* This code assumes that RGN_HPAGE != 0. */ 146 if ((REGION_NUMBER(addr) != RGN_HPAGE) || (addr & (HPAGE_SIZE - 1))) 147 addr = HPAGE_REGION_BASE; 148 else 149 addr = ALIGN(addr, HPAGE_SIZE); 150 for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) { 151 /* At this point: (!vmm || addr < vmm->vm_end). */ 152 if (REGION_OFFSET(addr) + len > RGN_MAP_LIMIT) 153 return -ENOMEM; 154 if (!vmm || (addr + len) <= vmm->vm_start) 155 return addr; 156 addr = ALIGN(vmm->vm_end, HPAGE_SIZE); 157 } 158 } 159 160 static int __init hugetlb_setup_sz(char *str) 161 { 162 u64 tr_pages; 163 unsigned long long size; 164 165 if (ia64_pal_vm_page_size(&tr_pages, NULL) != 0) 166 /* 167 * shouldn't happen, but just in case. 168 */ 169 tr_pages = 0x15557000UL; 170 171 size = memparse(str, &str); 172 if (*str || (size & (size-1)) || !(tr_pages & size) || 173 size <= PAGE_SIZE || 174 size >= (1UL << PAGE_SHIFT << MAX_ORDER)) { 175 printk(KERN_WARNING "Invalid huge page size specified\n"); 176 return 1; 177 } 178 179 hpage_shift = __ffs(size); 180 /* 181 * boot cpu already executed ia64_mmu_init, and has HPAGE_SHIFT_DEFAULT 182 * override here with new page shift. 183 */ 184 ia64_set_rr(HPAGE_REGION_BASE, hpage_shift << 2); 185 return 1; 186 } 187 __setup("hugepagesz=", hugetlb_setup_sz); 188