ia64/linux-2.6.18-xen.hg

view arch/m32r/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 * linux/arch/m32r/mm/ioremap.c
3 *
4 * Copyright (c) 2001, 2002 Hiroyuki Kondo
5 *
6 * Taken from mips version.
7 * (C) Copyright 1995 1996 Linus Torvalds
8 * (C) Copyright 2001 Ralf Baechle
9 */
11 /*
12 * This file is subject to the terms and conditions of the GNU General Public
13 * License. See the file "COPYING" in the main directory of this archive
14 * for more details.
15 *
16 */
18 #include <linux/module.h>
19 #include <asm/addrspace.h>
20 #include <asm/byteorder.h>
22 #include <linux/vmalloc.h>
23 #include <asm/io.h>
24 #include <asm/pgalloc.h>
25 #include <asm/cacheflush.h>
26 #include <asm/tlbflush.h>
28 static inline void
29 remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
30 unsigned long phys_addr, unsigned long flags)
31 {
32 unsigned long end;
33 unsigned long pfn;
34 pgprot_t pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | _PAGE_READ
35 | _PAGE_WRITE | flags);
37 address &= ~PMD_MASK;
38 end = address + size;
39 if (end > PMD_SIZE)
40 end = PMD_SIZE;
41 if (address >= end)
42 BUG();
43 pfn = phys_addr >> PAGE_SHIFT;
44 do {
45 if (!pte_none(*pte)) {
46 printk("remap_area_pte: page already exists\n");
47 BUG();
48 }
49 set_pte(pte, pfn_pte(pfn, pgprot));
50 address += PAGE_SIZE;
51 pfn++;
52 pte++;
53 } while (address && (address < end));
54 }
56 static inline int
57 remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
58 unsigned long phys_addr, unsigned long flags)
59 {
60 unsigned long end;
62 address &= ~PGDIR_MASK;
63 end = address + size;
64 if (end > PGDIR_SIZE)
65 end = PGDIR_SIZE;
66 phys_addr -= address;
67 if (address >= end)
68 BUG();
69 do {
70 pte_t * pte = pte_alloc_kernel(pmd, address);
71 if (!pte)
72 return -ENOMEM;
73 remap_area_pte(pte, address, end - address, address + phys_addr, flags);
74 address = (address + PMD_SIZE) & PMD_MASK;
75 pmd++;
76 } while (address && (address < end));
77 return 0;
78 }
80 static int
81 remap_area_pages(unsigned long address, unsigned long phys_addr,
82 unsigned long size, unsigned long flags)
83 {
84 int error;
85 pgd_t * dir;
86 unsigned long end = address + size;
88 phys_addr -= address;
89 dir = pgd_offset(&init_mm, address);
90 flush_cache_all();
91 if (address >= end)
92 BUG();
93 do {
94 pmd_t *pmd;
95 pmd = pmd_alloc(&init_mm, dir, address);
96 error = -ENOMEM;
97 if (!pmd)
98 break;
99 if (remap_area_pmd(pmd, address, end - address,
100 phys_addr + address, flags))
101 break;
102 error = 0;
103 address = (address + PGDIR_SIZE) & PGDIR_MASK;
104 dir++;
105 } while (address && (address < end));
106 flush_tlb_all();
107 return error;
108 }
110 /*
111 * Generic mapping function (not visible outside):
112 */
114 /*
115 * Remap an arbitrary physical address space into the kernel virtual
116 * address space. Needed when the kernel wants to access high addresses
117 * directly.
118 *
119 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
120 * have to convert them into an offset in a page-aligned mapping, but the
121 * caller shouldn't need to know that small detail.
122 */
124 #define IS_LOW512(addr) (!((unsigned long)(addr) & ~0x1fffffffUL))
126 void __iomem *
127 __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
128 {
129 void __iomem * addr;
130 struct vm_struct * area;
131 unsigned long offset, last_addr;
133 /* Don't allow wraparound or zero size */
134 last_addr = phys_addr + size - 1;
135 if (!size || last_addr < phys_addr)
136 return NULL;
138 /*
139 * Map objects in the low 512mb of address space using KSEG1, otherwise
140 * map using page tables.
141 */
142 if (IS_LOW512(phys_addr) && IS_LOW512(phys_addr + size - 1))
143 return (void *) KSEG1ADDR(phys_addr);
145 /*
146 * Don't allow anybody to remap normal RAM that we're using..
147 */
148 if (phys_addr < virt_to_phys(high_memory)) {
149 char *t_addr, *t_end;
150 struct page *page;
152 t_addr = __va(phys_addr);
153 t_end = t_addr + (size - 1);
155 for(page = virt_to_page(t_addr); page <= virt_to_page(t_end); page++)
156 if(!PageReserved(page))
157 return NULL;
158 }
160 /*
161 * Mappings have to be page-aligned
162 */
163 offset = phys_addr & ~PAGE_MASK;
164 phys_addr &= PAGE_MASK;
165 size = PAGE_ALIGN(last_addr + 1) - phys_addr;
167 /*
168 * Ok, go for it..
169 */
170 area = get_vm_area(size, VM_IOREMAP);
171 if (!area)
172 return NULL;
173 area->phys_addr = phys_addr;
174 addr = (void __iomem *) area->addr;
175 if (remap_area_pages((unsigned long)addr, phys_addr, size, flags)) {
176 vunmap((void __force *) addr);
177 return NULL;
178 }
180 return (void __iomem *) (offset + (char __iomem *)addr);
181 }
183 #define IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == KSEG1)
185 void iounmap(volatile void __iomem *addr)
186 {
187 if (!IS_KSEG1(addr))
188 vfree((void *) (PAGE_MASK & (unsigned long) addr));
189 }