This source file includes following definitions.
- __bad_pagetable
- __bad_page
- show_mem
- paging_init
- mem_init
- si_meminfo
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7 #include <linux/config.h>
8 #include <linux/signal.h>
9 #include <linux/sched.h>
10 #include <linux/head.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/string.h>
14 #include <linux/types.h>
15 #include <linux/ptrace.h>
16 #include <linux/mman.h>
17 #include <linux/mm.h>
18 #include <linux/swap.h>
19 #include <linux/smp.h>
20 #ifdef CONFIG_BLK_DEV_INITRD
21 #include <linux/blk.h>
22 #endif
23
24 #include <asm/system.h>
25 #include <asm/segment.h>
26 #include <asm/pgtable.h>
27 #include <asm/dma.h>
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29
30
31
32 #ifdef __SMP__
33 #undef USE_PENTIUM_MM
34 #endif
35
36 extern void die_if_kernel(char *,struct pt_regs *,long);
37 extern void show_net_buffers(void);
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51
52 pte_t * __bad_pagetable(void)
53 {
54 extern char empty_bad_page_table[PAGE_SIZE];
55
56 __asm__ __volatile__("cld ; rep ; stosl":
57 :"a" (pte_val(BAD_PAGE)),
58 "D" ((long) empty_bad_page_table),
59 "c" (PAGE_SIZE/4)
60 :"di","cx");
61 return (pte_t *) empty_bad_page_table;
62 }
63
64 pte_t __bad_page(void)
65 {
66 extern char empty_bad_page[PAGE_SIZE];
67
68 __asm__ __volatile__("cld ; rep ; stosl":
69 :"a" (0),
70 "D" ((long) empty_bad_page),
71 "c" (PAGE_SIZE/4)
72 :"di","cx");
73 return pte_mkdirty(mk_pte((unsigned long) empty_bad_page, PAGE_SHARED));
74 }
75
76 void show_mem(void)
77 {
78 int i,free = 0,total = 0,reserved = 0;
79 int shared = 0;
80
81 printk("Mem-info:\n");
82 show_free_areas();
83 printk("Free swap: %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10));
84 i = high_memory >> PAGE_SHIFT;
85 while (i-- > 0) {
86 total++;
87 if (mem_map[i].reserved)
88 reserved++;
89 else if (!mem_map[i].count)
90 free++;
91 else
92 shared += mem_map[i].count-1;
93 }
94 printk("%d pages of RAM\n",total);
95 printk("%d free pages\n",free);
96 printk("%d reserved pages\n",reserved);
97 printk("%d pages shared\n",shared);
98 show_buffers();
99 #ifdef CONFIG_NET
100 show_net_buffers();
101 #endif
102 }
103
104 extern unsigned long free_area_init(unsigned long, unsigned long);
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112
113 unsigned long paging_init(unsigned long start_mem, unsigned long end_mem)
114 {
115 pgd_t * pg_dir;
116 pte_t * pg_table;
117 unsigned long tmp;
118 unsigned long address;
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126
127 #if 0
128 memset((void *) 0, 0, PAGE_SIZE);
129 #endif
130 #ifdef __SMP__
131 smp_scan_config(0x0,0x400);
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135
136 smp_scan_config(639*0x400,0x400);
137 smp_scan_config(0xF0000,0x10000);
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144
145 #endif
146 #ifdef TEST_VERIFY_AREA
147 wp_works_ok = 0;
148 #endif
149 start_mem = PAGE_ALIGN(start_mem);
150 address = 0;
151 pg_dir = swapper_pg_dir;
152 while (address < end_mem) {
153 #ifdef USE_PENTIUM_MM
154 if (address <= end_mem + 4*1024*1024 &&
155 (x86_capability & 8)) {
156 #ifdef GAS_KNOWS_CR4
157 __asm__("movl %%cr4,%%eax\n\t"
158 "orl $16,%%eax\n\t"
159 "movl %%eax,%%cr4"
160 : : :"ax");
161 #else
162 __asm__(".byte 0x0f,0x20,0xe0\n\t"
163 "orl $16,%%eax\n\t"
164 ".byte 0x0f,0x22,0xe0"
165 : : :"ax");
166 #endif
167 wp_works_ok = 1;
168 pgd_val(pg_dir[0]) = _PAGE_TABLE | _PAGE_4M | address;
169 pgd_val(pg_dir[768]) = _PAGE_TABLE | _PAGE_4M | address;
170 pg_dir++;
171 address += 4*1024*1024;
172 continue;
173 }
174 #endif
175
176 pg_table = (pte_t *) (PAGE_MASK & pgd_val(pg_dir[768]));
177 if (!pg_table) {
178 pg_table = (pte_t *) start_mem;
179 start_mem += PAGE_SIZE;
180 }
181
182
183 pgd_val(pg_dir[0]) = _PAGE_TABLE | (unsigned long) pg_table;
184 pgd_val(pg_dir[768]) = _PAGE_TABLE | (unsigned long) pg_table;
185 pg_dir++;
186 for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) {
187 if (address < end_mem)
188 set_pte(pg_table, mk_pte(address, PAGE_SHARED));
189 else
190 pte_clear(pg_table);
191 address += PAGE_SIZE;
192 }
193 }
194 invalidate();
195 return free_area_init(start_mem, end_mem);
196 }
197
198 void mem_init(unsigned long start_mem, unsigned long end_mem)
199 {
200 unsigned long start_low_mem = PAGE_SIZE;
201 int codepages = 0;
202 int reservedpages = 0;
203 int datapages = 0;
204 unsigned long tmp;
205 extern int _etext;
206
207 end_mem &= PAGE_MASK;
208 high_memory = end_mem;
209
210
211 memset(empty_zero_page, 0, PAGE_SIZE);
212
213
214 start_low_mem = PAGE_ALIGN(start_low_mem);
215
216 #ifdef __SMP__
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220 start_low_mem += PAGE_SIZE;
221 start_low_mem = smp_alloc_memory(start_low_mem);
222 #endif
223 start_mem = PAGE_ALIGN(start_mem);
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230 while (start_low_mem < 0x9f000) {
231 mem_map[MAP_NR(start_low_mem)].reserved = 0;
232 start_low_mem += PAGE_SIZE;
233 }
234
235 while (start_mem < high_memory) {
236 mem_map[MAP_NR(start_mem)].reserved = 0;
237 start_mem += PAGE_SIZE;
238 }
239 for (tmp = 0 ; tmp < high_memory ; tmp += PAGE_SIZE) {
240 if (tmp >= MAX_DMA_ADDRESS)
241 mem_map[MAP_NR(tmp)].dma = 0;
242 if (mem_map[MAP_NR(tmp)].reserved) {
243 if (tmp >= 0xA0000 && tmp < 0x100000)
244 reservedpages++;
245 else if (tmp < (unsigned long) &_etext)
246 codepages++;
247 else
248 datapages++;
249 continue;
250 }
251 mem_map[MAP_NR(tmp)].count = 1;
252 #ifdef CONFIG_BLK_DEV_INITRD
253 if (!initrd_start || (tmp < initrd_start || tmp >=
254 initrd_end))
255 #endif
256 free_page(tmp);
257 }
258 tmp = nr_free_pages << PAGE_SHIFT;
259 printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data)\n",
260 tmp >> 10,
261 high_memory >> 10,
262 codepages << (PAGE_SHIFT-10),
263 reservedpages << (PAGE_SHIFT-10),
264 datapages << (PAGE_SHIFT-10));
265
266 if (wp_works_ok < 0) {
267 pg0[0] = pte_val(mk_pte(0, PAGE_READONLY));
268 invalidate();
269 __asm__ __volatile__("movb 0,%%al ; movb %%al,0": : :"ax", "memory");
270 pg0[0] = 0;
271 invalidate();
272 if (wp_works_ok < 0)
273 wp_works_ok = 0;
274 }
275 return;
276 }
277
278 void si_meminfo(struct sysinfo *val)
279 {
280 int i;
281
282 i = high_memory >> PAGE_SHIFT;
283 val->totalram = 0;
284 val->sharedram = 0;
285 val->freeram = nr_free_pages << PAGE_SHIFT;
286 val->bufferram = buffermem;
287 while (i-- > 0) {
288 if (mem_map[i].reserved)
289 continue;
290 val->totalram++;
291 if (!mem_map[i].count)
292 continue;
293 val->sharedram += mem_map[i].count-1;
294 }
295 val->totalram <<= PAGE_SHIFT;
296 val->sharedram <<= PAGE_SHIFT;
297 return;
298 }