ia64/linux-2.6.18-xen.hg

view arch/cris/mm/ioremap.c @ 647:a5bb490065f6

Fix the build after public header sync.
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Wed Aug 13 14:01:49 2008 +0100 (2008-08-13)
parents 831230e53067
children
line source
1 /*
2 * arch/cris/mm/ioremap.c
3 *
4 * Re-map IO memory to kernel address space so that we can access it.
5 * Needed for memory-mapped I/O devices mapped outside our normal DRAM
6 * window (that is, all memory-mapped I/O devices).
7 *
8 * (C) Copyright 1995 1996 Linus Torvalds
9 * CRIS-port by Axis Communications AB
10 */
12 #include <linux/vmalloc.h>
13 #include <asm/io.h>
14 #include <asm/pgalloc.h>
15 #include <asm/cacheflush.h>
16 #include <asm/tlbflush.h>
17 #include <asm/arch/memmap.h>
19 static inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
20 unsigned long phys_addr, pgprot_t prot)
21 {
22 unsigned long end;
24 address &= ~PMD_MASK;
25 end = address + size;
26 if (end > PMD_SIZE)
27 end = PMD_SIZE;
28 if (address >= end)
29 BUG();
30 do {
31 if (!pte_none(*pte)) {
32 printk("remap_area_pte: page already exists\n");
33 BUG();
34 }
35 set_pte(pte, mk_pte_phys(phys_addr, prot));
36 address += PAGE_SIZE;
37 phys_addr += PAGE_SIZE;
38 pte++;
39 } while (address && (address < end));
40 }
42 static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
43 unsigned long phys_addr, pgprot_t prot)
44 {
45 unsigned long end;
47 address &= ~PGDIR_MASK;
48 end = address + size;
49 if (end > PGDIR_SIZE)
50 end = PGDIR_SIZE;
51 phys_addr -= address;
52 if (address >= end)
53 BUG();
54 do {
55 pte_t * pte = pte_alloc_kernel(pmd, address);
56 if (!pte)
57 return -ENOMEM;
58 remap_area_pte(pte, address, end - address, address + phys_addr, prot);
59 address = (address + PMD_SIZE) & PMD_MASK;
60 pmd++;
61 } while (address && (address < end));
62 return 0;
63 }
65 static int remap_area_pages(unsigned long address, unsigned long phys_addr,
66 unsigned long size, pgprot_t prot)
67 {
68 int error;
69 pgd_t * dir;
70 unsigned long end = address + size;
72 phys_addr -= address;
73 dir = pgd_offset(&init_mm, address);
74 flush_cache_all();
75 if (address >= end)
76 BUG();
77 do {
78 pud_t *pud;
79 pmd_t *pmd;
81 error = -ENOMEM;
82 pud = pud_alloc(&init_mm, dir, address);
83 if (!pud)
84 break;
85 pmd = pmd_alloc(&init_mm, pud, address);
87 if (!pmd)
88 break;
89 if (remap_area_pmd(pmd, address, end - address,
90 phys_addr + address, prot))
91 break;
92 error = 0;
93 address = (address + PGDIR_SIZE) & PGDIR_MASK;
94 dir++;
95 } while (address && (address < end));
96 flush_tlb_all();
97 return error;
98 }
100 /*
101 * Generic mapping function (not visible outside):
102 */
104 /*
105 * Remap an arbitrary physical address space into the kernel virtual
106 * address space. Needed when the kernel wants to access high addresses
107 * directly.
108 *
109 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
110 * have to convert them into an offset in a page-aligned mapping, but the
111 * caller shouldn't need to know that small detail.
112 */
113 void __iomem * __ioremap_prot(unsigned long phys_addr, unsigned long size, pgprot_t prot)
114 {
115 void __iomem * addr;
116 struct vm_struct * area;
117 unsigned long offset, last_addr;
119 /* Don't allow wraparound or zero size */
120 last_addr = phys_addr + size - 1;
121 if (!size || last_addr < phys_addr)
122 return NULL;
124 /*
125 * Mappings have to be page-aligned
126 */
127 offset = phys_addr & ~PAGE_MASK;
128 phys_addr &= PAGE_MASK;
129 size = PAGE_ALIGN(last_addr+1) - phys_addr;
131 /*
132 * Ok, go for it..
133 */
134 area = get_vm_area(size, VM_IOREMAP);
135 if (!area)
136 return NULL;
137 addr = (void __iomem *)area->addr;
138 if (remap_area_pages((unsigned long) addr, phys_addr, size, prot)) {
139 vfree((void __force *)addr);
140 return NULL;
141 }
142 return (void __iomem *) (offset + (char __iomem *)addr);
143 }
145 void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
146 {
147 return __ioremap_prot(phys_addr, size,
148 __pgprot(_PAGE_PRESENT | __READABLE |
149 __WRITEABLE | _PAGE_GLOBAL |
150 _PAGE_KERNEL | flags));
151 }
153 /**
154 * ioremap_nocache - map bus memory into CPU space
155 * @offset: bus address of the memory
156 * @size: size of the resource to map
157 *
158 * Must be freed with iounmap.
159 */
161 void __iomem *ioremap_nocache (unsigned long phys_addr, unsigned long size)
162 {
163 return __ioremap(phys_addr | MEM_NON_CACHEABLE, size, 0);
164 }
166 void iounmap(volatile void __iomem *addr)
167 {
168 if (addr > high_memory)
169 return vfree((void *) (PAGE_MASK & (unsigned long) addr));
170 }