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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 | // SPDX-License-Identifier: GPL-2.0 /* * Re-map IO memory to kernel address space so that we can access it. * This is needed for high PCI addresses that aren't mapped in the * 640k-1MB IO memory area on PC's * * (C) Copyright 1995 1996 Linus Torvalds */ #include <linux/vmalloc.h> #include <linux/mm.h> #include <linux/sched.h> #include <linux/io.h> #include <linux/export.h> #include <asm/cacheflush.h> #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP static int __read_mostly ioremap_p4d_capable; static int __read_mostly ioremap_pud_capable; static int __read_mostly ioremap_pmd_capable; static int __read_mostly ioremap_huge_disabled; static int __init set_nohugeiomap(char *str) { ioremap_huge_disabled = 1; return 0; } early_param("nohugeiomap", set_nohugeiomap); void __init ioremap_huge_init(void) { if (!ioremap_huge_disabled) { if (arch_ioremap_p4d_supported()) ioremap_p4d_capable = 1; if (arch_ioremap_pud_supported()) ioremap_pud_capable = 1; if (arch_ioremap_pmd_supported()) ioremap_pmd_capable = 1; } } static inline int ioremap_p4d_enabled(void) { return ioremap_p4d_capable; } static inline int ioremap_pud_enabled(void) { return ioremap_pud_capable; } static inline int ioremap_pmd_enabled(void) { return ioremap_pmd_capable; } #else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */ static inline int ioremap_p4d_enabled(void) { return 0; } static inline int ioremap_pud_enabled(void) { return 0; } static inline int ioremap_pmd_enabled(void) { return 0; } #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ static int ioremap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot, pgtbl_mod_mask *mask) { pte_t *pte; u64 pfn; pfn = phys_addr >> PAGE_SHIFT; pte = pte_alloc_kernel_track(pmd, addr, mask); if (!pte) return -ENOMEM; do { BUG_ON(!pte_none(*pte)); set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot)); pfn++; } while (pte++, addr += PAGE_SIZE, addr != end); *mask |= PGTBL_PTE_MODIFIED; return 0; } static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { if (!ioremap_pmd_enabled()) return 0; if ((end - addr) != PMD_SIZE) return 0; if (!IS_ALIGNED(addr, PMD_SIZE)) return 0; if (!IS_ALIGNED(phys_addr, PMD_SIZE)) return 0; if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr)) return 0; return pmd_set_huge(pmd, phys_addr, prot); } static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot, pgtbl_mod_mask *mask) { pmd_t *pmd; unsigned long next; pmd = pmd_alloc_track(&init_mm, pud, addr, mask); if (!pmd) return -ENOMEM; do { next = pmd_addr_end(addr, end); if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) { *mask |= PGTBL_PMD_MODIFIED; continue; } if (ioremap_pte_range(pmd, addr, next, phys_addr, prot, mask)) return -ENOMEM; } while (pmd++, phys_addr += (next - addr), addr = next, addr != end); return 0; } static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { if (!ioremap_pud_enabled()) return 0; if ((end - addr) != PUD_SIZE) return 0; if (!IS_ALIGNED(addr, PUD_SIZE)) return 0; if (!IS_ALIGNED(phys_addr, PUD_SIZE)) return 0; if (pud_present(*pud) && !pud_free_pmd_page(pud, addr)) return 0; return pud_set_huge(pud, phys_addr, prot); } static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot, pgtbl_mod_mask *mask) { pud_t *pud; unsigned long next; pud = pud_alloc_track(&init_mm, p4d, addr, mask); if (!pud) return -ENOMEM; do { next = pud_addr_end(addr, end); if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot)) { *mask |= PGTBL_PUD_MODIFIED; continue; } if (ioremap_pmd_range(pud, addr, next, phys_addr, prot, mask)) return -ENOMEM; } while (pud++, phys_addr += (next - addr), addr = next, addr != end); return 0; } static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { if (!ioremap_p4d_enabled()) return 0; if ((end - addr) != P4D_SIZE) return 0; if (!IS_ALIGNED(addr, P4D_SIZE)) return 0; if (!IS_ALIGNED(phys_addr, P4D_SIZE)) return 0; if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr)) return 0; return p4d_set_huge(p4d, phys_addr, prot); } static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot, pgtbl_mod_mask *mask) { p4d_t *p4d; unsigned long next; p4d = p4d_alloc_track(&init_mm, pgd, addr, mask); if (!p4d) return -ENOMEM; do { next = p4d_addr_end(addr, end); if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) { *mask |= PGTBL_P4D_MODIFIED; continue; } if (ioremap_pud_range(p4d, addr, next, phys_addr, prot, mask)) return -ENOMEM; } while (p4d++, phys_addr += (next - addr), addr = next, addr != end); return 0; } int ioremap_page_range(unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { pgd_t *pgd; unsigned long start; unsigned long next; int err; pgtbl_mod_mask mask = 0; might_sleep(); BUG_ON(addr >= end); start = addr; pgd = pgd_offset_k(addr); do { next = pgd_addr_end(addr, end); err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot, &mask); if (err) break; } while (pgd++, phys_addr += (next - addr), addr = next, addr != end); flush_cache_vmap(start, end); if (mask & ARCH_PAGE_TABLE_SYNC_MASK) arch_sync_kernel_mappings(start, end); return err; } #ifdef CONFIG_GENERIC_IOREMAP void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot) { unsigned long offset, vaddr; phys_addr_t last_addr; struct vm_struct *area; /* Disallow wrap-around or zero size */ last_addr = addr + size - 1; if (!size || last_addr < addr) return NULL; /* Page-align mappings */ offset = addr & (~PAGE_MASK); addr -= offset; size = PAGE_ALIGN(size + offset); area = get_vm_area_caller(size, VM_IOREMAP, __builtin_return_address(0)); if (!area) return NULL; vaddr = (unsigned long)area->addr; if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) { free_vm_area(area); return NULL; } return (void __iomem *)(vaddr + offset); } EXPORT_SYMBOL(ioremap_prot); void iounmap(volatile void __iomem *addr) { vunmap((void *)((unsigned long)addr & PAGE_MASK)); } EXPORT_SYMBOL(iounmap); #endif /* CONFIG_GENERIC_IOREMAP */ |