arch/powerpc/mm/pgtable_64.c

   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 int __weak ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size, pgprot_t prot, int nid)
 107 {
 108         unsigned long i;
 109
 110         for (i = 0; i < size; i += PAGE_SIZE) {
 111                 int err = map_kernel_page(ea + i, pa + i, prot);
 112                 if (err) {
 113                         if (slab_is_available())
 114                                 unmap_kernel_range(ea, size);
 115                         else
 116                                 WARN_ON_ONCE(1); /* Should clean up */
 117                         return err;
 118                 }
 119         }
 120
 121         return 0;
 122 }
 123
 124 /**
 125  * __ioremap_at - Low level function to establish the page tables
 126  *                for an IO mapping
 127  */
 128 void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_t prot)
 129 {
 130         /* We don't support the 4K PFN hack with ioremap */
 131         if (pgprot_val(prot) & H_PAGE_4K_PFN)
 132                 return NULL;
 133
 134         if ((ea + size) >= (void *)IOREMAP_END) {
 135                 pr_warn("Outside the supported range\n");
 136                 return NULL;
 137         }
 138
 139         WARN_ON(pa & ~PAGE_MASK);
 140         WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
 141         WARN_ON(size & ~PAGE_MASK);
 142
 143         if (ioremap_range((unsigned long)ea, pa, size, prot, NUMA_NO_NODE))
 144                 return NULL;
 145
 146         return (void __iomem *)ea;
 147 }
 148
 149 /**
 150  * __iounmap_from - Low level function to tear down the page tables
 151  *                  for an IO mapping. This is used for mappings that
 152  *                  are manipulated manually, like partial unmapping of
 153  *                  PCI IOs or ISA space.
 154  */
 155 void __iounmap_at(void *ea, unsigned long size)
 156 {
 157         WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
 158         WARN_ON(size & ~PAGE_MASK);
 159
 160         unmap_kernel_range((unsigned long)ea, size);
 161 }
 162
 163 void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size,
 164                                 pgprot_t prot, void *caller)
 165 {
 166         phys_addr_t paligned;
 167         void __iomem *ret;
 168
 169         /*
 170          * Choose an address to map it to.
 171          * Once the imalloc system is running, we use it.
 172          * Before that, we map using addresses going
 173          * up from ioremap_bot.  imalloc will use
 174          * the addresses from ioremap_bot through
 175          * IMALLOC_END
 176          *
 177          */
 178         paligned = addr & PAGE_MASK;
 179         size = PAGE_ALIGN(addr + size) - paligned;
 180
 181         if ((size == 0) || (paligned == 0))
 182                 return NULL;
 183
 184         if (slab_is_available()) {
 185                 struct vm_struct *area;
 186
 187                 area = __get_vm_area_caller(size, VM_IOREMAP,
 188                                             ioremap_bot, IOREMAP_END,
 189                                             caller);
 190                 if (area == NULL)
 191                         return NULL;
 192
 193                 area->phys_addr = paligned;
 194                 ret = __ioremap_at(paligned, area->addr, size, prot);
 195         } else {
 196                 ret = __ioremap_at(paligned, (void *)ioremap_bot, size, prot);
 197                 if (ret)
 198                         ioremap_bot += size;
 199         }
 200
 201         if (ret)
 202                 ret += addr & ~PAGE_MASK;
 203         return ret;
 204 }
 205
 206 void __iomem * __ioremap(phys_addr_t addr, unsigned long size,
 207                          unsigned long flags)
 208 {
 209         return __ioremap_caller(addr, size, __pgprot(flags), __builtin_return_address(0));
 210 }
 211
 212 void __iomem * ioremap(phys_addr_t addr, unsigned long size)
 213 {
 214         pgprot_t prot = pgprot_noncached(PAGE_KERNEL);
 215         void *caller = __builtin_return_address(0);
 216
 217         if (ppc_md.ioremap)
 218                 return ppc_md.ioremap(addr, size, prot, caller);
 219         return __ioremap_caller(addr, size, prot, caller);
 220 }
 221
 222 void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size)
 223 {
 224         pgprot_t prot = pgprot_noncached_wc(PAGE_KERNEL);
 225         void *caller = __builtin_return_address(0);
 226
 227         if (ppc_md.ioremap)
 228                 return ppc_md.ioremap(addr, size, prot, caller);
 229         return __ioremap_caller(addr, size, prot, caller);
 230 }
 231
 232 void __iomem *ioremap_coherent(phys_addr_t addr, unsigned long size)
 233 {
 234         pgprot_t prot = pgprot_cached(PAGE_KERNEL);
 235         void *caller = __builtin_return_address(0);
 236
 237         if (ppc_md.ioremap)
 238                 return ppc_md.ioremap(addr, size, prot, caller);
 239         return __ioremap_caller(addr, size, prot, caller);
 240 }
 241
 242 void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size,
 243                              unsigned long flags)
 244 {
 245         pte_t pte = __pte(flags);
 246         void *caller = __builtin_return_address(0);
 247
 248         /* writeable implies dirty for kernel addresses */
 249         if (pte_write(pte))
 250                 pte = pte_mkdirty(pte);
 251
 252         /* we don't want to let _PAGE_EXEC leak out */
 253         pte = pte_exprotect(pte);
 254         /*
 255          * Force kernel mapping.
 256          */
 257         pte = pte_mkprivileged(pte);
 258
 259         if (ppc_md.ioremap)
 260                 return ppc_md.ioremap(addr, size, pte_pgprot(pte), caller);
 261         return __ioremap_caller(addr, size, pte_pgprot(pte), caller);
 262 }
 263
 264
 265 /*
 266  * Unmap an IO region and remove it from imalloc'd list.
 267  * Access to IO memory should be serialized by driver.
 268  */
 269 void __iounmap(volatile void __iomem *token)
 270 {
 271         void *addr;
 272
 273         if (!slab_is_available())
 274                 return;
 275
 276         addr = (void *) ((unsigned long __force)
 277                          PCI_FIX_ADDR(token) & PAGE_MASK);
 278         if ((unsigned long)addr < ioremap_bot) {
 279                 printk(KERN_WARNING "Attempt to iounmap early bolted mapping"
 280                        " at 0x%p\n", addr);
 281                 return;
 282         }
 283         vunmap(addr);
 284 }
 285
 286 void iounmap(volatile void __iomem *token)
 287 {
 288         if (ppc_md.iounmap)
 289                 ppc_md.iounmap(token);
 290         else
 291                 __iounmap(token);
 292 }
 293
 294 EXPORT_SYMBOL(ioremap);
 295 EXPORT_SYMBOL(ioremap_wc);
 296 EXPORT_SYMBOL(ioremap_prot);
 297 EXPORT_SYMBOL(__ioremap);
 298 EXPORT_SYMBOL(__ioremap_at);
 299 EXPORT_SYMBOL(iounmap);
 300 EXPORT_SYMBOL(__iounmap);
 301 EXPORT_SYMBOL(__iounmap_at);
 302
 303 #ifndef __PAGETABLE_PUD_FOLDED
 304 /* 4 level page table */
 305 struct page *pgd_page(pgd_t pgd)
 306 {
 307         if (pgd_is_leaf(pgd)) {
 308                 VM_WARN_ON(!pgd_huge(pgd));
 309                 return pte_page(pgd_pte(pgd));
 310         }
 311         return virt_to_page(pgd_page_vaddr(pgd));
 312 }
 313 #endif
 314
 315 struct page *pud_page(pud_t pud)
 316 {
 317         if (pud_is_leaf(pud)) {
 318                 VM_WARN_ON(!pud_huge(pud));
 319                 return pte_page(pud_pte(pud));
 320         }
 321         return virt_to_page(pud_page_vaddr(pud));
 322 }
 323
 324 /*
 325  * For hugepage we have pfn in the pmd, we use PTE_RPN_SHIFT bits for flags
 326  * For PTE page, we have a PTE_FRAG_SIZE (4K) aligned virtual address.
 327  */
 328 struct page *pmd_page(pmd_t pmd)
 329 {
 330         if (pmd_is_leaf(pmd)) {
 331                 VM_WARN_ON(!(pmd_large(pmd) || pmd_huge(pmd)));
 332                 return pte_page(pmd_pte(pmd));
 333         }
 334         return virt_to_page(pmd_page_vaddr(pmd));
 335 }
 336
 337 #ifdef CONFIG_STRICT_KERNEL_RWX
 338 void mark_rodata_ro(void)
 339 {
 340         if (!mmu_has_feature(MMU_FTR_KERNEL_RO)) {
 341                 pr_warn("Warning: Unable to mark rodata read only on this CPU.\n");
 342                 return;
 343         }
 344
 345         if (radix_enabled())
 346                 radix__mark_rodata_ro();
 347         else
 348                 hash__mark_rodata_ro();
 349
 350         // mark_initmem_nx() should have already run by now
 351         ptdump_check_wx();
 352 }
 353
 354 void mark_initmem_nx(void)
 355 {
 356         if (radix_enabled())
 357                 radix__mark_initmem_nx();
 358         else
 359                 hash__mark_initmem_nx();
 360 }
 361 #endif