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19#include <asm/iomap.h>
20#include <asm/pat.h>
21#include <linux/export.h>
22#include <linux/highmem.h>
23
24static int is_io_mapping_possible(resource_size_t base, unsigned long size)
25{
26#if !defined(CONFIG_X86_PAE) && defined(CONFIG_PHYS_ADDR_T_64BIT)
27
28 if (base + size > 0x100000000ULL)
29 return 0;
30#endif
31 return 1;
32}
33
34int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot)
35{
36 enum page_cache_mode pcm = _PAGE_CACHE_MODE_WC;
37 int ret;
38
39 if (!is_io_mapping_possible(base, size))
40 return -EINVAL;
41
42 ret = io_reserve_memtype(base, base + size, &pcm);
43 if (ret)
44 return ret;
45
46 *prot = __pgprot(__PAGE_KERNEL | cachemode2protval(pcm));
47 return 0;
48}
49EXPORT_SYMBOL_GPL(iomap_create_wc);
50
51void iomap_free(resource_size_t base, unsigned long size)
52{
53 io_free_memtype(base, base + size);
54}
55EXPORT_SYMBOL_GPL(iomap_free);
56
57void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
58{
59 unsigned long vaddr;
60 int idx, type;
61
62 preempt_disable();
63 pagefault_disable();
64
65 type = kmap_atomic_idx_push();
66 idx = type + KM_TYPE_NR * smp_processor_id();
67 vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
68 set_pte(kmap_pte - idx, pfn_pte(pfn, prot));
69 arch_flush_lazy_mmu_mode();
70
71 return (void *)vaddr;
72}
73
74
75
76
77void __iomem *
78iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
79{
80
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84
85
86
87 if (!pat_enabled() && pgprot2cachemode(prot) != _PAGE_CACHE_MODE_WB)
88 prot = __pgprot(__PAGE_KERNEL |
89 cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS));
90
91 return (void __force __iomem *) kmap_atomic_prot_pfn(pfn, prot);
92}
93EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn);
94
95void
96iounmap_atomic(void __iomem *kvaddr)
97{
98 unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
99
100 if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
101 vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
102 int idx, type;
103
104 type = kmap_atomic_idx();
105 idx = type + KM_TYPE_NR * smp_processor_id();
106
107#ifdef CONFIG_DEBUG_HIGHMEM
108 WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
109#endif
110
111
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115
116 kpte_clear_flush(kmap_pte-idx, vaddr);
117 kmap_atomic_idx_pop();
118 }
119
120 pagefault_enable();
121 preempt_enable();
122}
123EXPORT_SYMBOL_GPL(iounmap_atomic);
124