1 /* 2 * This file contains ioremap and related functions for 64-bit machines. 3 * 4 * Derived from arch/ppc64/mm/init.c 5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 6 * 7 * Modifications by Paul Mackerras (PowerMac) (paulus@samba.org) 8 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 9 * Copyright (C) 1996 Paul Mackerras 10 * 11 * Derived from "arch/i386/mm/init.c" 12 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 13 * 14 * Dave Engebretsen <engebret@us.ibm.com> 15 * Rework for PPC64 port. 16 * 17 * This program is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU General Public License 19 * as published by the Free Software Foundation; either version 20 * 2 of the License, or (at your option) any later version. 21 * 22 */ 23 24 #include <linux/signal.h> 25 #include <linux/sched.h> 26 #include <linux/kernel.h> 27 #include <linux/errno.h> 28 #include <linux/string.h> 29 #include <linux/export.h> 30 #include <linux/types.h> 31 #include <linux/mman.h> 32 #include <linux/mm.h> 33 #include <linux/swap.h> 34 #include <linux/stddef.h> 35 #include <linux/vmalloc.h> 36 #include <linux/slab.h> 37 #include <linux/hugetlb.h> 38 39 #include <asm/pgalloc.h> 40 #include <asm/page.h> 41 #include <asm/prom.h> 42 #include <asm/io.h> 43 #include <asm/mmu_context.h> 44 #include <asm/pgtable.h> 45 #include <asm/mmu.h> 46 #include <asm/smp.h> 47 #include <asm/machdep.h> 48 #include <asm/tlb.h> 49 #include <asm/processor.h> 50 #include <asm/cputable.h> 51 #include <asm/sections.h> 52 #include <asm/firmware.h> 53 #include <asm/dma.h> 54 55 #include <mm/mmu_decl.h> 56 57 58 #ifdef CONFIG_PPC_BOOK3S_64 59 /* 60 * partition table and process table for ISA 3.0 61 */ 62 struct prtb_entry *process_tb; 63 struct patb_entry *partition_tb; 64 /* 65 * page table size 66 */ 67 unsigned long __pte_index_size; 68 EXPORT_SYMBOL(__pte_index_size); 69 unsigned long __pmd_index_size; 70 EXPORT_SYMBOL(__pmd_index_size); 71 unsigned long __pud_index_size; 72 EXPORT_SYMBOL(__pud_index_size); 73 unsigned long __pgd_index_size; 74 EXPORT_SYMBOL(__pgd_index_size); 75 unsigned long __pud_cache_index; 76 EXPORT_SYMBOL(__pud_cache_index); 77 unsigned long __pte_table_size; 78 EXPORT_SYMBOL(__pte_table_size); 79 unsigned long __pmd_table_size; 80 EXPORT_SYMBOL(__pmd_table_size); 81 unsigned long __pud_table_size; 82 EXPORT_SYMBOL(__pud_table_size); 83 unsigned long __pgd_table_size; 84 EXPORT_SYMBOL(__pgd_table_size); 85 unsigned long __pmd_val_bits; 86 EXPORT_SYMBOL(__pmd_val_bits); 87 unsigned long __pud_val_bits; 88 EXPORT_SYMBOL(__pud_val_bits); 89 unsigned long __pgd_val_bits; 90 EXPORT_SYMBOL(__pgd_val_bits); 91 unsigned long __kernel_virt_start; 92 EXPORT_SYMBOL(__kernel_virt_start); 93 unsigned long __vmalloc_start; 94 EXPORT_SYMBOL(__vmalloc_start); 95 unsigned long __vmalloc_end; 96 EXPORT_SYMBOL(__vmalloc_end); 97 unsigned long __kernel_io_start; 98 EXPORT_SYMBOL(__kernel_io_start); 99 unsigned long __kernel_io_end; 100 struct page *vmemmap; 101 EXPORT_SYMBOL(vmemmap); 102 unsigned long __pte_frag_nr; 103 EXPORT_SYMBOL(__pte_frag_nr); 104 unsigned long __pte_frag_size_shift; 105 EXPORT_SYMBOL(__pte_frag_size_shift); 106 unsigned long ioremap_bot; 107 #else /* !CONFIG_PPC_BOOK3S_64 */ 108 unsigned long ioremap_bot = IOREMAP_BASE; 109 #endif 110 111 /** 112 * __ioremap_at - Low level function to establish the page tables 113 * for an IO mapping 114 */ 115 void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_t prot) 116 { 117 unsigned long i; 118 119 /* We don't support the 4K PFN hack with ioremap */ 120 if (pgprot_val(prot) & H_PAGE_4K_PFN) 121 return NULL; 122 123 if ((ea + size) >= (void *)IOREMAP_END) { 124 pr_warn("Outside the supported range\n"); 125 return NULL; 126 } 127 128 WARN_ON(pa & ~PAGE_MASK); 129 WARN_ON(((unsigned long)ea) & ~PAGE_MASK); 130 WARN_ON(size & ~PAGE_MASK); 131 132 for (i = 0; i < size; i += PAGE_SIZE) 133 if (map_kernel_page((unsigned long)ea + i, pa + i, prot)) 134 return NULL; 135 136 return (void __iomem *)ea; 137 } 138 139 /** 140 * __iounmap_from - Low level function to tear down the page tables 141 * for an IO mapping. This is used for mappings that 142 * are manipulated manually, like partial unmapping of 143 * PCI IOs or ISA space. 144 */ 145 void __iounmap_at(void *ea, unsigned long size) 146 { 147 WARN_ON(((unsigned long)ea) & ~PAGE_MASK); 148 WARN_ON(size & ~PAGE_MASK); 149 150 unmap_kernel_range((unsigned long)ea, size); 151 } 152 153 void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size, 154 pgprot_t prot, void *caller) 155 { 156 phys_addr_t paligned; 157 void __iomem *ret; 158 159 /* 160 * Choose an address to map it to. 161 * Once the imalloc system is running, we use it. 162 * Before that, we map using addresses going 163 * up from ioremap_bot. imalloc will use 164 * the addresses from ioremap_bot through 165 * IMALLOC_END 166 * 167 */ 168 paligned = addr & PAGE_MASK; 169 size = PAGE_ALIGN(addr + size) - paligned; 170 171 if ((size == 0) || (paligned == 0)) 172 return NULL; 173 174 if (slab_is_available()) { 175 struct vm_struct *area; 176 177 area = __get_vm_area_caller(size, VM_IOREMAP, 178 ioremap_bot, IOREMAP_END, 179 caller); 180 if (area == NULL) 181 return NULL; 182 183 area->phys_addr = paligned; 184 ret = __ioremap_at(paligned, area->addr, size, prot); 185 if (!ret) 186 vunmap(area->addr); 187 } else { 188 ret = __ioremap_at(paligned, (void *)ioremap_bot, size, prot); 189 if (ret) 190 ioremap_bot += size; 191 } 192 193 if (ret) 194 ret += addr & ~PAGE_MASK; 195 return ret; 196 } 197 198 void __iomem * __ioremap(phys_addr_t addr, unsigned long size, 199 unsigned long flags) 200 { 201 return __ioremap_caller(addr, size, __pgprot(flags), __builtin_return_address(0)); 202 } 203 204 void __iomem * ioremap(phys_addr_t addr, unsigned long size) 205 { 206 pgprot_t prot = pgprot_noncached(PAGE_KERNEL); 207 void *caller = __builtin_return_address(0); 208 209 if (ppc_md.ioremap) 210 return ppc_md.ioremap(addr, size, prot, caller); 211 return __ioremap_caller(addr, size, prot, caller); 212 } 213 214 void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size) 215 { 216 pgprot_t prot = pgprot_noncached_wc(PAGE_KERNEL); 217 void *caller = __builtin_return_address(0); 218 219 if (ppc_md.ioremap) 220 return ppc_md.ioremap(addr, size, prot, caller); 221 return __ioremap_caller(addr, size, prot, caller); 222 } 223 224 void __iomem *ioremap_coherent(phys_addr_t addr, unsigned long size) 225 { 226 pgprot_t prot = pgprot_cached(PAGE_KERNEL); 227 void *caller = __builtin_return_address(0); 228 229 if (ppc_md.ioremap) 230 return ppc_md.ioremap(addr, size, prot, caller); 231 return __ioremap_caller(addr, size, prot, caller); 232 } 233 234 void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, 235 unsigned long flags) 236 { 237 pte_t pte = __pte(flags); 238 void *caller = __builtin_return_address(0); 239 240 /* writeable implies dirty for kernel addresses */ 241 if (pte_write(pte)) 242 pte = pte_mkdirty(pte); 243 244 /* we don't want to let _PAGE_EXEC leak out */ 245 pte = pte_exprotect(pte); 246 /* 247 * Force kernel mapping. 248 */ 249 pte = pte_mkprivileged(pte); 250 251 if (ppc_md.ioremap) 252 return ppc_md.ioremap(addr, size, pte_pgprot(pte), caller); 253 return __ioremap_caller(addr, size, pte_pgprot(pte), caller); 254 } 255 256 257 /* 258 * Unmap an IO region and remove it from imalloc'd list. 259 * Access to IO memory should be serialized by driver. 260 */ 261 void __iounmap(volatile void __iomem *token) 262 { 263 void *addr; 264 265 if (!slab_is_available()) 266 return; 267 268 addr = (void *) ((unsigned long __force) 269 PCI_FIX_ADDR(token) & PAGE_MASK); 270 if ((unsigned long)addr < ioremap_bot) { 271 printk(KERN_WARNING "Attempt to iounmap early bolted mapping" 272 " at 0x%p\n", addr); 273 return; 274 } 275 vunmap(addr); 276 } 277 278 void iounmap(volatile void __iomem *token) 279 { 280 if (ppc_md.iounmap) 281 ppc_md.iounmap(token); 282 else 283 __iounmap(token); 284 } 285 286 EXPORT_SYMBOL(ioremap); 287 EXPORT_SYMBOL(ioremap_wc); 288 EXPORT_SYMBOL(ioremap_prot); 289 EXPORT_SYMBOL(__ioremap); 290 EXPORT_SYMBOL(__ioremap_at); 291 EXPORT_SYMBOL(iounmap); 292 EXPORT_SYMBOL(__iounmap); 293 EXPORT_SYMBOL(__iounmap_at); 294 295 #ifndef __PAGETABLE_PUD_FOLDED 296 /* 4 level page table */ 297 struct page *pgd_page(pgd_t pgd) 298 { 299 if (pgd_huge(pgd)) 300 return pte_page(pgd_pte(pgd)); 301 return virt_to_page(pgd_page_vaddr(pgd)); 302 } 303 #endif 304 305 struct page *pud_page(pud_t pud) 306 { 307 if (pud_huge(pud)) 308 return pte_page(pud_pte(pud)); 309 return virt_to_page(pud_page_vaddr(pud)); 310 } 311 312 /* 313 * For hugepage we have pfn in the pmd, we use PTE_RPN_SHIFT bits for flags 314 * For PTE page, we have a PTE_FRAG_SIZE (4K) aligned virtual address. 315 */ 316 struct page *pmd_page(pmd_t pmd) 317 { 318 if (pmd_large(pmd) || pmd_huge(pmd) || pmd_devmap(pmd)) 319 return pte_page(pmd_pte(pmd)); 320 return virt_to_page(pmd_page_vaddr(pmd)); 321 } 322 323 #ifdef CONFIG_STRICT_KERNEL_RWX 324 void mark_rodata_ro(void) 325 { 326 if (!mmu_has_feature(MMU_FTR_KERNEL_RO)) { 327 pr_warn("Warning: Unable to mark rodata read only on this CPU.\n"); 328 return; 329 } 330 331 if (radix_enabled()) 332 radix__mark_rodata_ro(); 333 else 334 hash__mark_rodata_ro(); 335 336 // mark_initmem_nx() should have already run by now 337 ptdump_check_wx(); 338 } 339 340 void mark_initmem_nx(void) 341 { 342 if (radix_enabled()) 343 radix__mark_initmem_nx(); 344 else 345 hash__mark_initmem_nx(); 346 } 347 #endif 348