1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * This file contains ioremap and related functions for 64-bit machines. 4 * 5 * Derived from arch/ppc64/mm/init.c 6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 7 * 8 * Modifications by Paul Mackerras (PowerMac) (paulus@samba.org) 9 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 10 * Copyright (C) 1996 Paul Mackerras 11 * 12 * Derived from "arch/i386/mm/init.c" 13 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 14 * 15 * Dave Engebretsen <engebret@us.ibm.com> 16 * Rework for PPC64 port. 17 */ 18 19 #include <linux/signal.h> 20 #include <linux/sched.h> 21 #include <linux/kernel.h> 22 #include <linux/errno.h> 23 #include <linux/string.h> 24 #include <linux/export.h> 25 #include <linux/types.h> 26 #include <linux/mman.h> 27 #include <linux/mm.h> 28 #include <linux/swap.h> 29 #include <linux/stddef.h> 30 #include <linux/vmalloc.h> 31 #include <linux/slab.h> 32 #include <linux/hugetlb.h> 33 34 #include <asm/pgalloc.h> 35 #include <asm/page.h> 36 #include <asm/prom.h> 37 #include <asm/io.h> 38 #include <asm/mmu_context.h> 39 #include <asm/pgtable.h> 40 #include <asm/mmu.h> 41 #include <asm/smp.h> 42 #include <asm/machdep.h> 43 #include <asm/tlb.h> 44 #include <asm/processor.h> 45 #include <asm/cputable.h> 46 #include <asm/sections.h> 47 #include <asm/firmware.h> 48 #include <asm/dma.h> 49 50 #include <mm/mmu_decl.h> 51 52 53 #ifdef CONFIG_PPC_BOOK3S_64 54 /* 55 * partition table and process table for ISA 3.0 56 */ 57 struct prtb_entry *process_tb; 58 struct patb_entry *partition_tb; 59 /* 60 * page table size 61 */ 62 unsigned long __pte_index_size; 63 EXPORT_SYMBOL(__pte_index_size); 64 unsigned long __pmd_index_size; 65 EXPORT_SYMBOL(__pmd_index_size); 66 unsigned long __pud_index_size; 67 EXPORT_SYMBOL(__pud_index_size); 68 unsigned long __pgd_index_size; 69 EXPORT_SYMBOL(__pgd_index_size); 70 unsigned long __pud_cache_index; 71 EXPORT_SYMBOL(__pud_cache_index); 72 unsigned long __pte_table_size; 73 EXPORT_SYMBOL(__pte_table_size); 74 unsigned long __pmd_table_size; 75 EXPORT_SYMBOL(__pmd_table_size); 76 unsigned long __pud_table_size; 77 EXPORT_SYMBOL(__pud_table_size); 78 unsigned long __pgd_table_size; 79 EXPORT_SYMBOL(__pgd_table_size); 80 unsigned long __pmd_val_bits; 81 EXPORT_SYMBOL(__pmd_val_bits); 82 unsigned long __pud_val_bits; 83 EXPORT_SYMBOL(__pud_val_bits); 84 unsigned long __pgd_val_bits; 85 EXPORT_SYMBOL(__pgd_val_bits); 86 unsigned long __kernel_virt_start; 87 EXPORT_SYMBOL(__kernel_virt_start); 88 unsigned long __vmalloc_start; 89 EXPORT_SYMBOL(__vmalloc_start); 90 unsigned long __vmalloc_end; 91 EXPORT_SYMBOL(__vmalloc_end); 92 unsigned long __kernel_io_start; 93 EXPORT_SYMBOL(__kernel_io_start); 94 unsigned long __kernel_io_end; 95 struct page *vmemmap; 96 EXPORT_SYMBOL(vmemmap); 97 unsigned long __pte_frag_nr; 98 EXPORT_SYMBOL(__pte_frag_nr); 99 unsigned long __pte_frag_size_shift; 100 EXPORT_SYMBOL(__pte_frag_size_shift); 101 unsigned long ioremap_bot; 102 #else /* !CONFIG_PPC_BOOK3S_64 */ 103 unsigned long ioremap_bot = IOREMAP_BASE; 104 #endif 105 106 /** 107 * __ioremap_at - Low level function to establish the page tables 108 * for an IO mapping 109 */ 110 void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_t prot) 111 { 112 unsigned long i; 113 114 /* We don't support the 4K PFN hack with ioremap */ 115 if (pgprot_val(prot) & H_PAGE_4K_PFN) 116 return NULL; 117 118 if ((ea + size) >= (void *)IOREMAP_END) { 119 pr_warn("Outside the supported range\n"); 120 return NULL; 121 } 122 123 WARN_ON(pa & ~PAGE_MASK); 124 WARN_ON(((unsigned long)ea) & ~PAGE_MASK); 125 WARN_ON(size & ~PAGE_MASK); 126 127 for (i = 0; i < size; i += PAGE_SIZE) 128 if (map_kernel_page((unsigned long)ea + i, pa + i, prot)) 129 return NULL; 130 131 return (void __iomem *)ea; 132 } 133 134 /** 135 * __iounmap_from - Low level function to tear down the page tables 136 * for an IO mapping. This is used for mappings that 137 * are manipulated manually, like partial unmapping of 138 * PCI IOs or ISA space. 139 */ 140 void __iounmap_at(void *ea, unsigned long size) 141 { 142 WARN_ON(((unsigned long)ea) & ~PAGE_MASK); 143 WARN_ON(size & ~PAGE_MASK); 144 145 unmap_kernel_range((unsigned long)ea, size); 146 } 147 148 void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size, 149 pgprot_t prot, void *caller) 150 { 151 phys_addr_t paligned; 152 void __iomem *ret; 153 154 /* 155 * Choose an address to map it to. 156 * Once the imalloc system is running, we use it. 157 * Before that, we map using addresses going 158 * up from ioremap_bot. imalloc will use 159 * the addresses from ioremap_bot through 160 * IMALLOC_END 161 * 162 */ 163 paligned = addr & PAGE_MASK; 164 size = PAGE_ALIGN(addr + size) - paligned; 165 166 if ((size == 0) || (paligned == 0)) 167 return NULL; 168 169 if (slab_is_available()) { 170 struct vm_struct *area; 171 172 area = __get_vm_area_caller(size, VM_IOREMAP, 173 ioremap_bot, IOREMAP_END, 174 caller); 175 if (area == NULL) 176 return NULL; 177 178 area->phys_addr = paligned; 179 ret = __ioremap_at(paligned, area->addr, size, prot); 180 if (!ret) 181 vunmap(area->addr); 182 } else { 183 ret = __ioremap_at(paligned, (void *)ioremap_bot, size, prot); 184 if (ret) 185 ioremap_bot += size; 186 } 187 188 if (ret) 189 ret += addr & ~PAGE_MASK; 190 return ret; 191 } 192 193 void __iomem * __ioremap(phys_addr_t addr, unsigned long size, 194 unsigned long flags) 195 { 196 return __ioremap_caller(addr, size, __pgprot(flags), __builtin_return_address(0)); 197 } 198 199 void __iomem * ioremap(phys_addr_t addr, unsigned long size) 200 { 201 pgprot_t prot = pgprot_noncached(PAGE_KERNEL); 202 void *caller = __builtin_return_address(0); 203 204 if (ppc_md.ioremap) 205 return ppc_md.ioremap(addr, size, prot, caller); 206 return __ioremap_caller(addr, size, prot, caller); 207 } 208 209 void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size) 210 { 211 pgprot_t prot = pgprot_noncached_wc(PAGE_KERNEL); 212 void *caller = __builtin_return_address(0); 213 214 if (ppc_md.ioremap) 215 return ppc_md.ioremap(addr, size, prot, caller); 216 return __ioremap_caller(addr, size, prot, caller); 217 } 218 219 void __iomem *ioremap_coherent(phys_addr_t addr, unsigned long size) 220 { 221 pgprot_t prot = pgprot_cached(PAGE_KERNEL); 222 void *caller = __builtin_return_address(0); 223 224 if (ppc_md.ioremap) 225 return ppc_md.ioremap(addr, size, prot, caller); 226 return __ioremap_caller(addr, size, prot, caller); 227 } 228 229 void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, 230 unsigned long flags) 231 { 232 pte_t pte = __pte(flags); 233 void *caller = __builtin_return_address(0); 234 235 /* writeable implies dirty for kernel addresses */ 236 if (pte_write(pte)) 237 pte = pte_mkdirty(pte); 238 239 /* we don't want to let _PAGE_EXEC leak out */ 240 pte = pte_exprotect(pte); 241 /* 242 * Force kernel mapping. 243 */ 244 pte = pte_mkprivileged(pte); 245 246 if (ppc_md.ioremap) 247 return ppc_md.ioremap(addr, size, pte_pgprot(pte), caller); 248 return __ioremap_caller(addr, size, pte_pgprot(pte), caller); 249 } 250 251 252 /* 253 * Unmap an IO region and remove it from imalloc'd list. 254 * Access to IO memory should be serialized by driver. 255 */ 256 void __iounmap(volatile void __iomem *token) 257 { 258 void *addr; 259 260 if (!slab_is_available()) 261 return; 262 263 addr = (void *) ((unsigned long __force) 264 PCI_FIX_ADDR(token) & PAGE_MASK); 265 if ((unsigned long)addr < ioremap_bot) { 266 printk(KERN_WARNING "Attempt to iounmap early bolted mapping" 267 " at 0x%p\n", addr); 268 return; 269 } 270 vunmap(addr); 271 } 272 273 void iounmap(volatile void __iomem *token) 274 { 275 if (ppc_md.iounmap) 276 ppc_md.iounmap(token); 277 else 278 __iounmap(token); 279 } 280 281 EXPORT_SYMBOL(ioremap); 282 EXPORT_SYMBOL(ioremap_wc); 283 EXPORT_SYMBOL(ioremap_prot); 284 EXPORT_SYMBOL(__ioremap); 285 EXPORT_SYMBOL(__ioremap_at); 286 EXPORT_SYMBOL(iounmap); 287 EXPORT_SYMBOL(__iounmap); 288 EXPORT_SYMBOL(__iounmap_at); 289 290 #ifndef __PAGETABLE_PUD_FOLDED 291 /* 4 level page table */ 292 struct page *pgd_page(pgd_t pgd) 293 { 294 if (pgd_huge(pgd)) 295 return pte_page(pgd_pte(pgd)); 296 return virt_to_page(pgd_page_vaddr(pgd)); 297 } 298 #endif 299 300 struct page *pud_page(pud_t pud) 301 { 302 if (pud_huge(pud)) 303 return pte_page(pud_pte(pud)); 304 return virt_to_page(pud_page_vaddr(pud)); 305 } 306 307 /* 308 * For hugepage we have pfn in the pmd, we use PTE_RPN_SHIFT bits for flags 309 * For PTE page, we have a PTE_FRAG_SIZE (4K) aligned virtual address. 310 */ 311 struct page *pmd_page(pmd_t pmd) 312 { 313 if (pmd_large(pmd) || pmd_huge(pmd) || pmd_devmap(pmd)) 314 return pte_page(pmd_pte(pmd)); 315 return virt_to_page(pmd_page_vaddr(pmd)); 316 } 317 318 #ifdef CONFIG_STRICT_KERNEL_RWX 319 void mark_rodata_ro(void) 320 { 321 if (!mmu_has_feature(MMU_FTR_KERNEL_RO)) { 322 pr_warn("Warning: Unable to mark rodata read only on this CPU.\n"); 323 return; 324 } 325 326 if (radix_enabled()) 327 radix__mark_rodata_ro(); 328 else 329 hash__mark_rodata_ro(); 330 331 // mark_initmem_nx() should have already run by now 332 ptdump_check_wx(); 333 } 334 335 void mark_initmem_nx(void) 336 { 337 if (radix_enabled()) 338 radix__mark_initmem_nx(); 339 else 340 hash__mark_initmem_nx(); 341 } 342 #endif 343