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Commit | Line | Data |
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540aca06 | 1 | #include <linux/ioport.h> |
e5b2bb55 | 2 | #include <linux/swap.h> |
540aca06 | 3 | |
e5b2bb55 | 4 | #include <asm/cacheflush.h> |
f765090a | 5 | #include <asm/e820.h> |
4fcb2083 | 6 | #include <asm/init.h> |
e5b2bb55 | 7 | #include <asm/page.h> |
540aca06 | 8 | #include <asm/page_types.h> |
e5b2bb55 PE |
9 | #include <asm/sections.h> |
10 | #include <asm/system.h> | |
f765090a PE |
11 | #include <asm/tlbflush.h> |
12 | ||
298af9d8 PE |
13 | unsigned long __initdata e820_table_start; |
14 | unsigned long __meminitdata e820_table_end; | |
15 | unsigned long __meminitdata e820_table_top; | |
f765090a PE |
16 | |
17 | int after_bootmem; | |
18 | ||
19 | int direct_gbpages | |
20 | #ifdef CONFIG_DIRECT_GBPAGES | |
21 | = 1 | |
22 | #endif | |
23 | ; | |
24 | ||
89388913 PE |
25 | int nx_enabled; |
26 | ||
27 | #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) | |
28 | static int disable_nx __cpuinitdata; | |
29 | ||
30 | /* | |
31 | * noexec = on|off | |
32 | * | |
33 | * Control non-executable mappings for processes. | |
34 | * | |
35 | * on Enable | |
36 | * off Disable | |
37 | */ | |
38 | static int __init noexec_setup(char *str) | |
39 | { | |
40 | if (!str) | |
41 | return -EINVAL; | |
42 | if (!strncmp(str, "on", 2)) { | |
43 | __supported_pte_mask |= _PAGE_NX; | |
44 | disable_nx = 0; | |
45 | } else if (!strncmp(str, "off", 3)) { | |
46 | disable_nx = 1; | |
47 | __supported_pte_mask &= ~_PAGE_NX; | |
48 | } | |
49 | return 0; | |
50 | } | |
51 | early_param("noexec", noexec_setup); | |
52 | #endif | |
53 | ||
54 | #ifdef CONFIG_X86_PAE | |
55 | static void __init set_nx(void) | |
56 | { | |
57 | unsigned int v[4], l, h; | |
58 | ||
59 | if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) { | |
60 | cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]); | |
61 | ||
62 | if ((v[3] & (1 << 20)) && !disable_nx) { | |
63 | rdmsr(MSR_EFER, l, h); | |
64 | l |= EFER_NX; | |
65 | wrmsr(MSR_EFER, l, h); | |
66 | nx_enabled = 1; | |
67 | __supported_pte_mask |= _PAGE_NX; | |
68 | } | |
69 | } | |
70 | } | |
71 | #else | |
72 | static inline void set_nx(void) | |
73 | { | |
74 | } | |
75 | #endif | |
76 | ||
77 | #ifdef CONFIG_X86_64 | |
78 | void __cpuinit check_efer(void) | |
79 | { | |
80 | unsigned long efer; | |
81 | ||
82 | rdmsrl(MSR_EFER, efer); | |
83 | if (!(efer & EFER_NX) || disable_nx) | |
84 | __supported_pte_mask &= ~_PAGE_NX; | |
85 | } | |
86 | #endif | |
87 | ||
f765090a PE |
88 | static void __init find_early_table_space(unsigned long end, int use_pse, |
89 | int use_gbpages) | |
90 | { | |
91 | unsigned long puds, pmds, ptes, tables, start; | |
92 | ||
93 | puds = (end + PUD_SIZE - 1) >> PUD_SHIFT; | |
94 | tables = roundup(puds * sizeof(pud_t), PAGE_SIZE); | |
95 | ||
96 | if (use_gbpages) { | |
97 | unsigned long extra; | |
98 | ||
99 | extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT); | |
100 | pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT; | |
101 | } else | |
102 | pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; | |
103 | ||
104 | tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE); | |
105 | ||
106 | if (use_pse) { | |
107 | unsigned long extra; | |
108 | ||
109 | extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT); | |
110 | #ifdef CONFIG_X86_32 | |
111 | extra += PMD_SIZE; | |
112 | #endif | |
113 | ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
114 | } else | |
115 | ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
116 | ||
117 | tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE); | |
118 | ||
119 | #ifdef CONFIG_X86_32 | |
120 | /* for fixmap */ | |
121 | tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE); | |
122 | #endif | |
123 | ||
124 | /* | |
125 | * RED-PEN putting page tables only on node 0 could | |
126 | * cause a hotspot and fill up ZONE_DMA. The page tables | |
127 | * need roughly 0.5KB per GB. | |
128 | */ | |
129 | #ifdef CONFIG_X86_32 | |
130 | start = 0x7000; | |
298af9d8 | 131 | e820_table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT, |
f765090a PE |
132 | tables, PAGE_SIZE); |
133 | #else /* CONFIG_X86_64 */ | |
134 | start = 0x8000; | |
298af9d8 | 135 | e820_table_start = find_e820_area(start, end, tables, PAGE_SIZE); |
f765090a | 136 | #endif |
298af9d8 | 137 | if (e820_table_start == -1UL) |
f765090a PE |
138 | panic("Cannot find space for the kernel page tables"); |
139 | ||
298af9d8 PE |
140 | e820_table_start >>= PAGE_SHIFT; |
141 | e820_table_end = e820_table_start; | |
142 | e820_table_top = e820_table_start + (tables >> PAGE_SHIFT); | |
f765090a PE |
143 | |
144 | printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n", | |
298af9d8 | 145 | end, e820_table_start << PAGE_SHIFT, e820_table_top << PAGE_SHIFT); |
f765090a PE |
146 | } |
147 | ||
148 | struct map_range { | |
149 | unsigned long start; | |
150 | unsigned long end; | |
151 | unsigned page_size_mask; | |
152 | }; | |
153 | ||
154 | #ifdef CONFIG_X86_32 | |
155 | #define NR_RANGE_MR 3 | |
156 | #else /* CONFIG_X86_64 */ | |
157 | #define NR_RANGE_MR 5 | |
158 | #endif | |
159 | ||
dc9dd5cc JB |
160 | static int __meminit save_mr(struct map_range *mr, int nr_range, |
161 | unsigned long start_pfn, unsigned long end_pfn, | |
162 | unsigned long page_size_mask) | |
f765090a PE |
163 | { |
164 | if (start_pfn < end_pfn) { | |
165 | if (nr_range >= NR_RANGE_MR) | |
166 | panic("run out of range for init_memory_mapping\n"); | |
167 | mr[nr_range].start = start_pfn<<PAGE_SHIFT; | |
168 | mr[nr_range].end = end_pfn<<PAGE_SHIFT; | |
169 | mr[nr_range].page_size_mask = page_size_mask; | |
170 | nr_range++; | |
171 | } | |
172 | ||
173 | return nr_range; | |
174 | } | |
175 | ||
176 | #ifdef CONFIG_X86_64 | |
177 | static void __init init_gbpages(void) | |
178 | { | |
179 | if (direct_gbpages && cpu_has_gbpages) | |
180 | printk(KERN_INFO "Using GB pages for direct mapping\n"); | |
181 | else | |
182 | direct_gbpages = 0; | |
183 | } | |
184 | #else | |
185 | static inline void init_gbpages(void) | |
186 | { | |
187 | } | |
188 | #endif | |
189 | ||
190 | /* | |
191 | * Setup the direct mapping of the physical memory at PAGE_OFFSET. | |
192 | * This runs before bootmem is initialized and gets pages directly from | |
193 | * the physical memory. To access them they are temporarily mapped. | |
194 | */ | |
195 | unsigned long __init_refok init_memory_mapping(unsigned long start, | |
196 | unsigned long end) | |
197 | { | |
198 | unsigned long page_size_mask = 0; | |
199 | unsigned long start_pfn, end_pfn; | |
c77a3b59 | 200 | unsigned long ret = 0; |
f765090a | 201 | unsigned long pos; |
f765090a PE |
202 | |
203 | struct map_range mr[NR_RANGE_MR]; | |
204 | int nr_range, i; | |
205 | int use_pse, use_gbpages; | |
206 | ||
207 | printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end); | |
208 | ||
209 | if (!after_bootmem) | |
210 | init_gbpages(); | |
211 | ||
212 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
213 | /* | |
214 | * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages. | |
215 | * This will simplify cpa(), which otherwise needs to support splitting | |
216 | * large pages into small in interrupt context, etc. | |
217 | */ | |
218 | use_pse = use_gbpages = 0; | |
219 | #else | |
220 | use_pse = cpu_has_pse; | |
221 | use_gbpages = direct_gbpages; | |
222 | #endif | |
223 | ||
f765090a PE |
224 | set_nx(); |
225 | if (nx_enabled) | |
226 | printk(KERN_INFO "NX (Execute Disable) protection: active\n"); | |
f765090a PE |
227 | |
228 | /* Enable PSE if available */ | |
229 | if (cpu_has_pse) | |
230 | set_in_cr4(X86_CR4_PSE); | |
231 | ||
232 | /* Enable PGE if available */ | |
233 | if (cpu_has_pge) { | |
234 | set_in_cr4(X86_CR4_PGE); | |
235 | __supported_pte_mask |= _PAGE_GLOBAL; | |
236 | } | |
f765090a PE |
237 | |
238 | if (use_gbpages) | |
239 | page_size_mask |= 1 << PG_LEVEL_1G; | |
240 | if (use_pse) | |
241 | page_size_mask |= 1 << PG_LEVEL_2M; | |
242 | ||
243 | memset(mr, 0, sizeof(mr)); | |
244 | nr_range = 0; | |
245 | ||
246 | /* head if not big page alignment ? */ | |
247 | start_pfn = start >> PAGE_SHIFT; | |
248 | pos = start_pfn << PAGE_SHIFT; | |
249 | #ifdef CONFIG_X86_32 | |
250 | /* | |
251 | * Don't use a large page for the first 2/4MB of memory | |
252 | * because there are often fixed size MTRRs in there | |
253 | * and overlapping MTRRs into large pages can cause | |
254 | * slowdowns. | |
255 | */ | |
256 | if (pos == 0) | |
257 | end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT); | |
258 | else | |
259 | end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) | |
260 | << (PMD_SHIFT - PAGE_SHIFT); | |
261 | #else /* CONFIG_X86_64 */ | |
262 | end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT) | |
263 | << (PMD_SHIFT - PAGE_SHIFT); | |
264 | #endif | |
265 | if (end_pfn > (end >> PAGE_SHIFT)) | |
266 | end_pfn = end >> PAGE_SHIFT; | |
267 | if (start_pfn < end_pfn) { | |
268 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0); | |
269 | pos = end_pfn << PAGE_SHIFT; | |
270 | } | |
271 | ||
272 | /* big page (2M) range */ | |
273 | start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) | |
274 | << (PMD_SHIFT - PAGE_SHIFT); | |
275 | #ifdef CONFIG_X86_32 | |
276 | end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); | |
277 | #else /* CONFIG_X86_64 */ | |
278 | end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT) | |
279 | << (PUD_SHIFT - PAGE_SHIFT); | |
280 | if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT))) | |
281 | end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)); | |
282 | #endif | |
283 | ||
284 | if (start_pfn < end_pfn) { | |
285 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, | |
286 | page_size_mask & (1<<PG_LEVEL_2M)); | |
287 | pos = end_pfn << PAGE_SHIFT; | |
288 | } | |
289 | ||
290 | #ifdef CONFIG_X86_64 | |
291 | /* big page (1G) range */ | |
292 | start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT) | |
293 | << (PUD_SHIFT - PAGE_SHIFT); | |
294 | end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT); | |
295 | if (start_pfn < end_pfn) { | |
296 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, | |
297 | page_size_mask & | |
298 | ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G))); | |
299 | pos = end_pfn << PAGE_SHIFT; | |
300 | } | |
301 | ||
302 | /* tail is not big page (1G) alignment */ | |
303 | start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) | |
304 | << (PMD_SHIFT - PAGE_SHIFT); | |
305 | end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); | |
306 | if (start_pfn < end_pfn) { | |
307 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, | |
308 | page_size_mask & (1<<PG_LEVEL_2M)); | |
309 | pos = end_pfn << PAGE_SHIFT; | |
310 | } | |
311 | #endif | |
312 | ||
313 | /* tail is not big page (2M) alignment */ | |
314 | start_pfn = pos>>PAGE_SHIFT; | |
315 | end_pfn = end>>PAGE_SHIFT; | |
316 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0); | |
317 | ||
318 | /* try to merge same page size and continuous */ | |
319 | for (i = 0; nr_range > 1 && i < nr_range - 1; i++) { | |
320 | unsigned long old_start; | |
321 | if (mr[i].end != mr[i+1].start || | |
322 | mr[i].page_size_mask != mr[i+1].page_size_mask) | |
323 | continue; | |
324 | /* move it */ | |
325 | old_start = mr[i].start; | |
326 | memmove(&mr[i], &mr[i+1], | |
327 | (nr_range - 1 - i) * sizeof(struct map_range)); | |
328 | mr[i--].start = old_start; | |
329 | nr_range--; | |
330 | } | |
331 | ||
332 | for (i = 0; i < nr_range; i++) | |
333 | printk(KERN_DEBUG " %010lx - %010lx page %s\n", | |
334 | mr[i].start, mr[i].end, | |
335 | (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":( | |
336 | (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k")); | |
337 | ||
338 | /* | |
339 | * Find space for the kernel direct mapping tables. | |
340 | * | |
341 | * Later we should allocate these tables in the local node of the | |
342 | * memory mapped. Unfortunately this is done currently before the | |
343 | * nodes are discovered. | |
344 | */ | |
345 | if (!after_bootmem) | |
346 | find_early_table_space(end, use_pse, use_gbpages); | |
347 | ||
348 | #ifdef CONFIG_X86_32 | |
349 | for (i = 0; i < nr_range; i++) | |
e53fb04f PE |
350 | kernel_physical_mapping_init(mr[i].start, mr[i].end, |
351 | mr[i].page_size_mask); | |
f765090a PE |
352 | ret = end; |
353 | #else /* CONFIG_X86_64 */ | |
354 | for (i = 0; i < nr_range; i++) | |
355 | ret = kernel_physical_mapping_init(mr[i].start, mr[i].end, | |
356 | mr[i].page_size_mask); | |
357 | #endif | |
358 | ||
359 | #ifdef CONFIG_X86_32 | |
360 | early_ioremap_page_table_range_init(); | |
361 | ||
362 | load_cr3(swapper_pg_dir); | |
363 | #endif | |
364 | ||
365 | #ifdef CONFIG_X86_64 | |
366 | if (!after_bootmem) | |
367 | mmu_cr4_features = read_cr4(); | |
368 | #endif | |
369 | __flush_tlb_all(); | |
370 | ||
298af9d8 PE |
371 | if (!after_bootmem && e820_table_end > e820_table_start) |
372 | reserve_early(e820_table_start << PAGE_SHIFT, | |
373 | e820_table_end << PAGE_SHIFT, "PGTABLE"); | |
f765090a PE |
374 | |
375 | if (!after_bootmem) | |
376 | early_memtest(start, end); | |
377 | ||
378 | return ret >> PAGE_SHIFT; | |
379 | } | |
380 | ||
e5b2bb55 | 381 | |
540aca06 PE |
382 | /* |
383 | * devmem_is_allowed() checks to see if /dev/mem access to a certain address | |
384 | * is valid. The argument is a physical page number. | |
385 | * | |
386 | * | |
387 | * On x86, access has to be given to the first megabyte of ram because that area | |
388 | * contains bios code and data regions used by X and dosemu and similar apps. | |
389 | * Access has to be given to non-kernel-ram areas as well, these contain the PCI | |
390 | * mmio resources as well as potential bios/acpi data regions. | |
391 | */ | |
392 | int devmem_is_allowed(unsigned long pagenr) | |
393 | { | |
394 | if (pagenr <= 256) | |
395 | return 1; | |
396 | if (iomem_is_exclusive(pagenr << PAGE_SHIFT)) | |
397 | return 0; | |
398 | if (!page_is_ram(pagenr)) | |
399 | return 1; | |
400 | return 0; | |
401 | } | |
402 | ||
e5b2bb55 PE |
403 | void free_init_pages(char *what, unsigned long begin, unsigned long end) |
404 | { | |
405 | unsigned long addr = begin; | |
406 | ||
407 | if (addr >= end) | |
408 | return; | |
409 | ||
410 | /* | |
411 | * If debugging page accesses then do not free this memory but | |
412 | * mark them not present - any buggy init-section access will | |
413 | * create a kernel page fault: | |
414 | */ | |
415 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
416 | printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n", | |
417 | begin, PAGE_ALIGN(end)); | |
418 | set_memory_np(begin, (end - begin) >> PAGE_SHIFT); | |
419 | #else | |
420 | /* | |
421 | * We just marked the kernel text read only above, now that | |
422 | * we are going to free part of that, we need to make that | |
423 | * writeable first. | |
424 | */ | |
425 | set_memory_rw(begin, (end - begin) >> PAGE_SHIFT); | |
426 | ||
427 | printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); | |
428 | ||
429 | for (; addr < end; addr += PAGE_SIZE) { | |
430 | ClearPageReserved(virt_to_page(addr)); | |
431 | init_page_count(virt_to_page(addr)); | |
432 | memset((void *)(addr & ~(PAGE_SIZE-1)), | |
433 | POISON_FREE_INITMEM, PAGE_SIZE); | |
434 | free_page(addr); | |
435 | totalram_pages++; | |
436 | } | |
437 | #endif | |
438 | } | |
439 | ||
440 | void free_initmem(void) | |
441 | { | |
442 | free_init_pages("unused kernel memory", | |
443 | (unsigned long)(&__init_begin), | |
444 | (unsigned long)(&__init_end)); | |
445 | } | |
731ddea6 PE |
446 | |
447 | #ifdef CONFIG_BLK_DEV_INITRD | |
448 | void free_initrd_mem(unsigned long start, unsigned long end) | |
449 | { | |
450 | free_init_pages("initrd memory", start, end); | |
451 | } | |
452 | #endif |