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29#include <linux/export.h>
30#include <linux/kernel.h>
31#include <linux/types.h>
32#include <linux/vmalloc.h>
33#include <linux/init.h>
34#include <linux/mm_types.h>
35#include <linux/pgtable.h>
36#include <linux/memblock.h>
37
38#include <asm/pgalloc.h>
39#include <linux/io.h>
40#include <asm/mmu.h>
41#include <asm/sections.h>
42#include <asm/fixmap.h>
43
44unsigned long ioremap_base;
45unsigned long ioremap_bot;
46EXPORT_SYMBOL(ioremap_bot);
47
48static void __iomem *__ioremap(phys_addr_t addr, unsigned long size,
49 unsigned long flags)
50{
51 unsigned long v, i;
52 phys_addr_t p;
53 int err;
54
55
56
57
58
59
60
61 p = addr & PAGE_MASK;
62 size = PAGE_ALIGN(addr + size) - p;
63
64
65
66
67
68
69
70
71 if (mem_init_done &&
72 p >= memory_start && p < virt_to_phys(high_memory) &&
73 !(p >= __virt_to_phys((phys_addr_t)__bss_stop) &&
74 p < __virt_to_phys((phys_addr_t)__bss_stop))) {
75 pr_warn("__ioremap(): phys addr "PTE_FMT" is RAM lr %ps\n",
76 (unsigned long)p, __builtin_return_address(0));
77 return NULL;
78 }
79
80 if (size == 0)
81 return NULL;
82
83
84
85
86
87
88
89
90
91
92
93
94 if (mem_init_done) {
95 struct vm_struct *area;
96 area = get_vm_area(size, VM_IOREMAP);
97 if (area == NULL)
98 return NULL;
99 v = (unsigned long) area->addr;
100 } else {
101 v = (ioremap_bot -= size);
102 }
103
104 if ((flags & _PAGE_PRESENT) == 0)
105 flags |= _PAGE_KERNEL;
106 if (flags & _PAGE_NO_CACHE)
107 flags |= _PAGE_GUARDED;
108
109 err = 0;
110 for (i = 0; i < size && err == 0; i += PAGE_SIZE)
111 err = map_page(v + i, p + i, flags);
112 if (err) {
113 if (mem_init_done)
114 vfree((void *)v);
115 return NULL;
116 }
117
118 return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
119}
120
121void __iomem *ioremap(phys_addr_t addr, unsigned long size)
122{
123 return __ioremap(addr, size, _PAGE_NO_CACHE);
124}
125EXPORT_SYMBOL(ioremap);
126
127void iounmap(volatile void __iomem *addr)
128{
129 if ((__force void *)addr > high_memory &&
130 (unsigned long) addr < ioremap_bot)
131 vfree((void *) (PAGE_MASK & (unsigned long) addr));
132}
133EXPORT_SYMBOL(iounmap);
134
135
136int map_page(unsigned long va, phys_addr_t pa, int flags)
137{
138 p4d_t *p4d;
139 pud_t *pud;
140 pmd_t *pd;
141 pte_t *pg;
142 int err = -ENOMEM;
143
144
145 p4d = p4d_offset(pgd_offset_k(va), va);
146 pud = pud_offset(p4d, va);
147 pd = pmd_offset(pud, va);
148
149 pg = pte_alloc_kernel(pd, va);
150
151
152 if (pg != NULL) {
153 err = 0;
154 set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
155 __pgprot(flags)));
156 if (unlikely(mem_init_done))
157 _tlbie(va);
158 }
159 return err;
160}
161
162
163
164
165void __init mapin_ram(void)
166{
167 unsigned long v, p, s, f;
168
169 v = CONFIG_KERNEL_START;
170 p = memory_start;
171 for (s = 0; s < lowmem_size; s += PAGE_SIZE) {
172 f = _PAGE_PRESENT | _PAGE_ACCESSED |
173 _PAGE_SHARED | _PAGE_HWEXEC;
174 if ((char *) v < _stext || (char *) v >= _etext)
175 f |= _PAGE_WRENABLE;
176 else
177
178
179 f |= _PAGE_USER;
180 map_page(v, p, f);
181 v += PAGE_SIZE;
182 p += PAGE_SIZE;
183 }
184}
185
186
187#define is_power_of_2(x) ((x) != 0 && (((x) & ((x) - 1)) == 0))
188
189
190
191
192
193
194static int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep)
195{
196 pgd_t *pgd;
197 p4d_t *p4d;
198 pud_t *pud;
199 pmd_t *pmd;
200 pte_t *pte;
201 int retval = 0;
202
203 pgd = pgd_offset(mm, addr & PAGE_MASK);
204 if (pgd) {
205 p4d = p4d_offset(pgd, addr & PAGE_MASK);
206 pud = pud_offset(p4d, addr & PAGE_MASK);
207 pmd = pmd_offset(pud, addr & PAGE_MASK);
208 if (pmd_present(*pmd)) {
209 pte = pte_offset_kernel(pmd, addr & PAGE_MASK);
210 if (pte) {
211 retval = 1;
212 *ptep = pte;
213 }
214 }
215 }
216 return retval;
217}
218
219
220
221
222unsigned long iopa(unsigned long addr)
223{
224 unsigned long pa;
225
226 pte_t *pte;
227 struct mm_struct *mm;
228
229
230
231
232 if (addr < TASK_SIZE)
233 mm = current->mm;
234 else
235 mm = &init_mm;
236
237 pa = 0;
238 if (get_pteptr(mm, addr, &pte))
239 pa = (pte_val(*pte) & PAGE_MASK) | (addr & ~PAGE_MASK);
240
241 return pa;
242}
243
244__ref pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
245{
246 if (mem_init_done)
247 return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
248 else
249 return memblock_alloc_try_nid(PAGE_SIZE, PAGE_SIZE,
250 MEMBLOCK_LOW_LIMIT,
251 memory_start + kernel_tlb,
252 NUMA_NO_NODE);
253}
254
255void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
256{
257 unsigned long address = __fix_to_virt(idx);
258
259 if (idx >= __end_of_fixed_addresses)
260 BUG();
261
262 map_page(address, phys, pgprot_val(flags));
263}
264