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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 | /* * 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> #include <asm/pgtable.h> #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP 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_pud_supported()) ioremap_pud_capable = 1; if (arch_ioremap_pmd_supported()) ioremap_pmd_capable = 1; } } 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_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) { pte_t *pte; u64 pfn; pfn = phys_addr >> PAGE_SHIFT; pte = pte_alloc_kernel(pmd, addr); 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); return 0; } static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { pmd_t *pmd; unsigned long next; phys_addr -= addr; pmd = pmd_alloc(&init_mm, pud, addr); if (!pmd) return -ENOMEM; do { next = pmd_addr_end(addr, end); if (ioremap_pmd_enabled() && ((next - addr) == PMD_SIZE) && IS_ALIGNED(phys_addr + addr, PMD_SIZE) && pmd_free_pte_page(pmd)) { if (pmd_set_huge(pmd, phys_addr + addr, prot)) continue; } if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot)) return -ENOMEM; } while (pmd++, addr = next, addr != end); return 0; } static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { pud_t *pud; unsigned long next; phys_addr -= addr; pud = pud_alloc(&init_mm, pgd, addr); if (!pud) return -ENOMEM; do { next = pud_addr_end(addr, end); if (ioremap_pud_enabled() && ((next - addr) == PUD_SIZE) && IS_ALIGNED(phys_addr + addr, PUD_SIZE) && pud_free_pmd_page(pud)) { if (pud_set_huge(pud, phys_addr + addr, prot)) continue; } if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot)) return -ENOMEM; } while (pud++, 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; BUG_ON(addr >= end); start = addr; phys_addr -= addr; pgd = pgd_offset_k(addr); do { next = pgd_addr_end(addr, end); err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot); if (err) break; } while (pgd++, addr = next, addr != end); flush_cache_vmap(start, end); return err; } EXPORT_SYMBOL_GPL(ioremap_page_range); |