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 */
8 #include <linux/vmalloc.h>
9 #include <linux/mm.h>
10 #include <linux/sched.h>
11 #include <linux/io.h>
12 #include <asm/cacheflush.h>
13 #include <asm/pgtable.h>
14
15 static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
16 unsigned long end, unsigned long phys_addr, pgprot_t prot)
17 {
18 pte_t *pte;
19 unsigned long pfn;
20
21 pfn = phys_addr >> PAGE_SHIFT;
22 pte = pte_alloc_kernel(pmd, addr);
23 if (!pte)
24 return -ENOMEM;
25 do {
26 BUG_ON(!pte_none(*pte));
27 set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
28 pfn++;
29 } while (pte++, addr += PAGE_SIZE, addr != end);
30 return 0;
31 }
32
33 static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
34 unsigned long end, unsigned long phys_addr, pgprot_t prot)
35 {
36 pmd_t *pmd;
37 unsigned long next;
38
39 phys_addr -= addr;
40 pmd = pmd_alloc(&init_mm, pud, addr);
41 if (!pmd)
42 return -ENOMEM;
43 do {
44 next = pmd_addr_end(addr, end);
45 if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
46 return -ENOMEM;
47 } while (pmd++, addr = next, addr != end);
48 return 0;
49 }
50
51 static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
52 unsigned long end, unsigned long phys_addr, pgprot_t prot)
53 {
54 pud_t *pud;
55 unsigned long next;
56
57 phys_addr -= addr;
58 pud = pud_alloc(&init_mm, pgd, addr);
59 if (!pud)
60 return -ENOMEM;
61 do {
62 next = pud_addr_end(addr, end);
63 if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
64 return -ENOMEM;
65 } while (pud++, addr = next, addr != end);
66 return 0;
67 }
68
69 int ioremap_page_range(unsigned long addr,
70 unsigned long end, unsigned long phys_addr, pgprot_t prot)
71 {
72 pgd_t *pgd;
73 unsigned long start;
74 unsigned long next;
75 int err;
76
77 BUG_ON(addr >= end);
78
79 start = addr;
80 phys_addr -= addr;
81 pgd = pgd_offset_k(addr);
82 do {
83 next = pgd_addr_end(addr, end);
84 err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot);
85 if (err)
86 break;
87 } while (pgd++, addr = next, addr != end);
88
89 flush_cache_vmap(start, end);
90
91 return err;
92 }
93
|
This page was automatically generated by the
LXR engine.
|