Commit | Line | Data |
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74588d8b HS |
1 | /* |
2 | * Re-map IO memory to kernel address space so that we can access it. | |
3 | * This is needed for high PCI addresses that aren't mapped in the | |
4 | * 640k-1MB IO memory area on PC's | |
5 | * | |
6 | * (C) Copyright 1995 1996 Linus Torvalds | |
7 | */ | |
74588d8b HS |
8 | #include <linux/vmalloc.h> |
9 | #include <linux/mm.h> | |
e8edc6e0 | 10 | #include <linux/sched.h> |
74588d8b HS |
11 | #include <asm/cacheflush.h> |
12 | #include <asm/pgtable.h> | |
13 | ||
14 | static int ioremap_pte_range(pmd_t *pmd, unsigned long addr, | |
15 | unsigned long end, unsigned long phys_addr, pgprot_t prot) | |
16 | { | |
17 | pte_t *pte; | |
18 | unsigned long pfn; | |
19 | ||
20 | pfn = phys_addr >> PAGE_SHIFT; | |
21 | pte = pte_alloc_kernel(pmd, addr); | |
22 | if (!pte) | |
23 | return -ENOMEM; | |
24 | do { | |
25 | BUG_ON(!pte_none(*pte)); | |
26 | set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot)); | |
27 | pfn++; | |
28 | } while (pte++, addr += PAGE_SIZE, addr != end); | |
29 | return 0; | |
30 | } | |
31 | ||
32 | static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr, | |
33 | unsigned long end, unsigned long phys_addr, pgprot_t prot) | |
34 | { | |
35 | pmd_t *pmd; | |
36 | unsigned long next; | |
37 | ||
38 | phys_addr -= addr; | |
39 | pmd = pmd_alloc(&init_mm, pud, addr); | |
40 | if (!pmd) | |
41 | return -ENOMEM; | |
42 | do { | |
43 | next = pmd_addr_end(addr, end); | |
44 | if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot)) | |
45 | return -ENOMEM; | |
46 | } while (pmd++, addr = next, addr != end); | |
47 | return 0; | |
48 | } | |
49 | ||
50 | static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr, | |
51 | unsigned long end, unsigned long phys_addr, pgprot_t prot) | |
52 | { | |
53 | pud_t *pud; | |
54 | unsigned long next; | |
55 | ||
56 | phys_addr -= addr; | |
57 | pud = pud_alloc(&init_mm, pgd, addr); | |
58 | if (!pud) | |
59 | return -ENOMEM; | |
60 | do { | |
61 | next = pud_addr_end(addr, end); | |
62 | if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot)) | |
63 | return -ENOMEM; | |
64 | } while (pud++, addr = next, addr != end); | |
65 | return 0; | |
66 | } | |
67 | ||
68 | int ioremap_page_range(unsigned long addr, | |
69 | unsigned long end, unsigned long phys_addr, pgprot_t prot) | |
70 | { | |
71 | pgd_t *pgd; | |
72 | unsigned long start; | |
73 | unsigned long next; | |
74 | int err; | |
75 | ||
76 | BUG_ON(addr >= end); | |
77 | ||
74588d8b HS |
78 | start = addr; |
79 | phys_addr -= addr; | |
80 | pgd = pgd_offset_k(addr); | |
81 | do { | |
82 | next = pgd_addr_end(addr, end); | |
83 | err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot); | |
84 | if (err) | |
85 | break; | |
86 | } while (pgd++, addr = next, addr != end); | |
87 | ||
db71daab | 88 | flush_cache_vmap(start, end); |
74588d8b HS |
89 | |
90 | return err; | |
91 | } |