diff options
author | Ingo Molnar <mingo@elte.hu> | 2009-03-06 10:44:14 -0500 |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-03-06 10:45:01 -0500 |
commit | f0ef03985130287c6c84ebe69416cf790e6cc00e (patch) | |
tree | 3ecb04cc4d82e5fc3ae5f1747e6da172ae8cbcb7 /arch/x86/mm/init.c | |
parent | 16097439703bcd38e9fe5608c12add6dacb825ea (diff) | |
parent | 31bbed527e7039203920c51c9fb48c27aed0820c (diff) |
Merge branch 'x86/core' into tracing/textedit
Conflicts:
arch/x86/Kconfig
block/blktrace.c
kernel/irq/handle.c
Semantic conflict:
kernel/trace/blktrace.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/mm/init.c')
-rw-r--r-- | arch/x86/mm/init.c | 393 |
1 files changed, 393 insertions, 0 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c new file mode 100644 index 000000000000..6d63e3d1253d --- /dev/null +++ b/arch/x86/mm/init.c | |||
@@ -0,0 +1,393 @@ | |||
1 | #include <linux/ioport.h> | ||
2 | #include <linux/swap.h> | ||
3 | |||
4 | #include <asm/cacheflush.h> | ||
5 | #include <asm/e820.h> | ||
6 | #include <asm/init.h> | ||
7 | #include <asm/page.h> | ||
8 | #include <asm/page_types.h> | ||
9 | #include <asm/sections.h> | ||
10 | #include <asm/system.h> | ||
11 | #include <asm/tlbflush.h> | ||
12 | |||
13 | unsigned long __initdata e820_table_start; | ||
14 | unsigned long __meminitdata e820_table_end; | ||
15 | unsigned long __meminitdata e820_table_top; | ||
16 | |||
17 | int after_bootmem; | ||
18 | |||
19 | int direct_gbpages | ||
20 | #ifdef CONFIG_DIRECT_GBPAGES | ||
21 | = 1 | ||
22 | #endif | ||
23 | ; | ||
24 | |||
25 | static void __init find_early_table_space(unsigned long end, int use_pse, | ||
26 | int use_gbpages) | ||
27 | { | ||
28 | unsigned long puds, pmds, ptes, tables, start; | ||
29 | |||
30 | puds = (end + PUD_SIZE - 1) >> PUD_SHIFT; | ||
31 | tables = roundup(puds * sizeof(pud_t), PAGE_SIZE); | ||
32 | |||
33 | if (use_gbpages) { | ||
34 | unsigned long extra; | ||
35 | |||
36 | extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT); | ||
37 | pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT; | ||
38 | } else | ||
39 | pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; | ||
40 | |||
41 | tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE); | ||
42 | |||
43 | if (use_pse) { | ||
44 | unsigned long extra; | ||
45 | |||
46 | extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT); | ||
47 | #ifdef CONFIG_X86_32 | ||
48 | extra += PMD_SIZE; | ||
49 | #endif | ||
50 | ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT; | ||
51 | } else | ||
52 | ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT; | ||
53 | |||
54 | tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE); | ||
55 | |||
56 | #ifdef CONFIG_X86_32 | ||
57 | /* for fixmap */ | ||
58 | tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE); | ||
59 | #endif | ||
60 | |||
61 | /* | ||
62 | * RED-PEN putting page tables only on node 0 could | ||
63 | * cause a hotspot and fill up ZONE_DMA. The page tables | ||
64 | * need roughly 0.5KB per GB. | ||
65 | */ | ||
66 | #ifdef CONFIG_X86_32 | ||
67 | start = 0x7000; | ||
68 | e820_table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT, | ||
69 | tables, PAGE_SIZE); | ||
70 | #else /* CONFIG_X86_64 */ | ||
71 | start = 0x8000; | ||
72 | e820_table_start = find_e820_area(start, end, tables, PAGE_SIZE); | ||
73 | #endif | ||
74 | if (e820_table_start == -1UL) | ||
75 | panic("Cannot find space for the kernel page tables"); | ||
76 | |||
77 | e820_table_start >>= PAGE_SHIFT; | ||
78 | e820_table_end = e820_table_start; | ||
79 | e820_table_top = e820_table_start + (tables >> PAGE_SHIFT); | ||
80 | |||
81 | printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n", | ||
82 | end, e820_table_start << PAGE_SHIFT, e820_table_top << PAGE_SHIFT); | ||
83 | } | ||
84 | |||
85 | struct map_range { | ||
86 | unsigned long start; | ||
87 | unsigned long end; | ||
88 | unsigned page_size_mask; | ||
89 | }; | ||
90 | |||
91 | #ifdef CONFIG_X86_32 | ||
92 | #define NR_RANGE_MR 3 | ||
93 | #else /* CONFIG_X86_64 */ | ||
94 | #define NR_RANGE_MR 5 | ||
95 | #endif | ||
96 | |||
97 | static int save_mr(struct map_range *mr, int nr_range, | ||
98 | unsigned long start_pfn, unsigned long end_pfn, | ||
99 | unsigned long page_size_mask) | ||
100 | { | ||
101 | if (start_pfn < end_pfn) { | ||
102 | if (nr_range >= NR_RANGE_MR) | ||
103 | panic("run out of range for init_memory_mapping\n"); | ||
104 | mr[nr_range].start = start_pfn<<PAGE_SHIFT; | ||
105 | mr[nr_range].end = end_pfn<<PAGE_SHIFT; | ||
106 | mr[nr_range].page_size_mask = page_size_mask; | ||
107 | nr_range++; | ||
108 | } | ||
109 | |||
110 | return nr_range; | ||
111 | } | ||
112 | |||
113 | #ifdef CONFIG_X86_64 | ||
114 | static void __init init_gbpages(void) | ||
115 | { | ||
116 | if (direct_gbpages && cpu_has_gbpages) | ||
117 | printk(KERN_INFO "Using GB pages for direct mapping\n"); | ||
118 | else | ||
119 | direct_gbpages = 0; | ||
120 | } | ||
121 | #else | ||
122 | static inline void init_gbpages(void) | ||
123 | { | ||
124 | } | ||
125 | #endif | ||
126 | |||
127 | /* | ||
128 | * Setup the direct mapping of the physical memory at PAGE_OFFSET. | ||
129 | * This runs before bootmem is initialized and gets pages directly from | ||
130 | * the physical memory. To access them they are temporarily mapped. | ||
131 | */ | ||
132 | unsigned long __init_refok init_memory_mapping(unsigned long start, | ||
133 | unsigned long end) | ||
134 | { | ||
135 | unsigned long page_size_mask = 0; | ||
136 | unsigned long start_pfn, end_pfn; | ||
137 | unsigned long pos; | ||
138 | unsigned long ret; | ||
139 | |||
140 | struct map_range mr[NR_RANGE_MR]; | ||
141 | int nr_range, i; | ||
142 | int use_pse, use_gbpages; | ||
143 | |||
144 | printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end); | ||
145 | |||
146 | if (!after_bootmem) | ||
147 | init_gbpages(); | ||
148 | |||
149 | #ifdef CONFIG_DEBUG_PAGEALLOC | ||
150 | /* | ||
151 | * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages. | ||
152 | * This will simplify cpa(), which otherwise needs to support splitting | ||
153 | * large pages into small in interrupt context, etc. | ||
154 | */ | ||
155 | use_pse = use_gbpages = 0; | ||
156 | #else | ||
157 | use_pse = cpu_has_pse; | ||
158 | use_gbpages = direct_gbpages; | ||
159 | #endif | ||
160 | |||
161 | #ifdef CONFIG_X86_32 | ||
162 | #ifdef CONFIG_X86_PAE | ||
163 | set_nx(); | ||
164 | if (nx_enabled) | ||
165 | printk(KERN_INFO "NX (Execute Disable) protection: active\n"); | ||
166 | #endif | ||
167 | |||
168 | /* Enable PSE if available */ | ||
169 | if (cpu_has_pse) | ||
170 | set_in_cr4(X86_CR4_PSE); | ||
171 | |||
172 | /* Enable PGE if available */ | ||
173 | if (cpu_has_pge) { | ||
174 | set_in_cr4(X86_CR4_PGE); | ||
175 | __supported_pte_mask |= _PAGE_GLOBAL; | ||
176 | } | ||
177 | #endif | ||
178 | |||
179 | if (use_gbpages) | ||
180 | page_size_mask |= 1 << PG_LEVEL_1G; | ||
181 | if (use_pse) | ||
182 | page_size_mask |= 1 << PG_LEVEL_2M; | ||
183 | |||
184 | memset(mr, 0, sizeof(mr)); | ||
185 | nr_range = 0; | ||
186 | |||
187 | /* head if not big page alignment ? */ | ||
188 | start_pfn = start >> PAGE_SHIFT; | ||
189 | pos = start_pfn << PAGE_SHIFT; | ||
190 | #ifdef CONFIG_X86_32 | ||
191 | /* | ||
192 | * Don't use a large page for the first 2/4MB of memory | ||
193 | * because there are often fixed size MTRRs in there | ||
194 | * and overlapping MTRRs into large pages can cause | ||
195 | * slowdowns. | ||
196 | */ | ||
197 | if (pos == 0) | ||
198 | end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT); | ||
199 | else | ||
200 | end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) | ||
201 | << (PMD_SHIFT - PAGE_SHIFT); | ||
202 | #else /* CONFIG_X86_64 */ | ||
203 | end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT) | ||
204 | << (PMD_SHIFT - PAGE_SHIFT); | ||
205 | #endif | ||
206 | if (end_pfn > (end >> PAGE_SHIFT)) | ||
207 | end_pfn = end >> PAGE_SHIFT; | ||
208 | if (start_pfn < end_pfn) { | ||
209 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0); | ||
210 | pos = end_pfn << PAGE_SHIFT; | ||
211 | } | ||
212 | |||
213 | /* big page (2M) range */ | ||
214 | start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) | ||
215 | << (PMD_SHIFT - PAGE_SHIFT); | ||
216 | #ifdef CONFIG_X86_32 | ||
217 | end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); | ||
218 | #else /* CONFIG_X86_64 */ | ||
219 | end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT) | ||
220 | << (PUD_SHIFT - PAGE_SHIFT); | ||
221 | if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT))) | ||
222 | end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)); | ||
223 | #endif | ||
224 | |||
225 | if (start_pfn < end_pfn) { | ||
226 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, | ||
227 | page_size_mask & (1<<PG_LEVEL_2M)); | ||
228 | pos = end_pfn << PAGE_SHIFT; | ||
229 | } | ||
230 | |||
231 | #ifdef CONFIG_X86_64 | ||
232 | /* big page (1G) range */ | ||
233 | start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT) | ||
234 | << (PUD_SHIFT - PAGE_SHIFT); | ||
235 | end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT); | ||
236 | if (start_pfn < end_pfn) { | ||
237 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, | ||
238 | page_size_mask & | ||
239 | ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G))); | ||
240 | pos = end_pfn << PAGE_SHIFT; | ||
241 | } | ||
242 | |||
243 | /* tail is not big page (1G) alignment */ | ||
244 | start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) | ||
245 | << (PMD_SHIFT - PAGE_SHIFT); | ||
246 | end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); | ||
247 | if (start_pfn < end_pfn) { | ||
248 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, | ||
249 | page_size_mask & (1<<PG_LEVEL_2M)); | ||
250 | pos = end_pfn << PAGE_SHIFT; | ||
251 | } | ||
252 | #endif | ||
253 | |||
254 | /* tail is not big page (2M) alignment */ | ||
255 | start_pfn = pos>>PAGE_SHIFT; | ||
256 | end_pfn = end>>PAGE_SHIFT; | ||
257 | nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0); | ||
258 | |||
259 | /* try to merge same page size and continuous */ | ||
260 | for (i = 0; nr_range > 1 && i < nr_range - 1; i++) { | ||
261 | unsigned long old_start; | ||
262 | if (mr[i].end != mr[i+1].start || | ||
263 | mr[i].page_size_mask != mr[i+1].page_size_mask) | ||
264 | continue; | ||
265 | /* move it */ | ||
266 | old_start = mr[i].start; | ||
267 | memmove(&mr[i], &mr[i+1], | ||
268 | (nr_range - 1 - i) * sizeof(struct map_range)); | ||
269 | mr[i--].start = old_start; | ||
270 | nr_range--; | ||
271 | } | ||
272 | |||
273 | for (i = 0; i < nr_range; i++) | ||
274 | printk(KERN_DEBUG " %010lx - %010lx page %s\n", | ||
275 | mr[i].start, mr[i].end, | ||
276 | (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":( | ||
277 | (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k")); | ||
278 | |||
279 | /* | ||
280 | * Find space for the kernel direct mapping tables. | ||
281 | * | ||
282 | * Later we should allocate these tables in the local node of the | ||
283 | * memory mapped. Unfortunately this is done currently before the | ||
284 | * nodes are discovered. | ||
285 | */ | ||
286 | if (!after_bootmem) | ||
287 | find_early_table_space(end, use_pse, use_gbpages); | ||
288 | |||
289 | #ifdef CONFIG_X86_32 | ||
290 | for (i = 0; i < nr_range; i++) | ||
291 | kernel_physical_mapping_init(mr[i].start, mr[i].end, | ||
292 | mr[i].page_size_mask); | ||
293 | ret = end; | ||
294 | #else /* CONFIG_X86_64 */ | ||
295 | for (i = 0; i < nr_range; i++) | ||
296 | ret = kernel_physical_mapping_init(mr[i].start, mr[i].end, | ||
297 | mr[i].page_size_mask); | ||
298 | #endif | ||
299 | |||
300 | #ifdef CONFIG_X86_32 | ||
301 | early_ioremap_page_table_range_init(); | ||
302 | |||
303 | load_cr3(swapper_pg_dir); | ||
304 | #endif | ||
305 | |||
306 | #ifdef CONFIG_X86_64 | ||
307 | if (!after_bootmem) | ||
308 | mmu_cr4_features = read_cr4(); | ||
309 | #endif | ||
310 | __flush_tlb_all(); | ||
311 | |||
312 | if (!after_bootmem && e820_table_end > e820_table_start) | ||
313 | reserve_early(e820_table_start << PAGE_SHIFT, | ||
314 | e820_table_end << PAGE_SHIFT, "PGTABLE"); | ||
315 | |||
316 | if (!after_bootmem) | ||
317 | early_memtest(start, end); | ||
318 | |||
319 | return ret >> PAGE_SHIFT; | ||
320 | } | ||
321 | |||
322 | |||
323 | /* | ||
324 | * devmem_is_allowed() checks to see if /dev/mem access to a certain address | ||
325 | * is valid. The argument is a physical page number. | ||
326 | * | ||
327 | * | ||
328 | * On x86, access has to be given to the first megabyte of ram because that area | ||
329 | * contains bios code and data regions used by X and dosemu and similar apps. | ||
330 | * Access has to be given to non-kernel-ram areas as well, these contain the PCI | ||
331 | * mmio resources as well as potential bios/acpi data regions. | ||
332 | */ | ||
333 | int devmem_is_allowed(unsigned long pagenr) | ||
334 | { | ||
335 | if (pagenr <= 256) | ||
336 | return 1; | ||
337 | if (iomem_is_exclusive(pagenr << PAGE_SHIFT)) | ||
338 | return 0; | ||
339 | if (!page_is_ram(pagenr)) | ||
340 | return 1; | ||
341 | return 0; | ||
342 | } | ||
343 | |||
344 | void free_init_pages(char *what, unsigned long begin, unsigned long end) | ||
345 | { | ||
346 | unsigned long addr = begin; | ||
347 | |||
348 | if (addr >= end) | ||
349 | return; | ||
350 | |||
351 | /* | ||
352 | * If debugging page accesses then do not free this memory but | ||
353 | * mark them not present - any buggy init-section access will | ||
354 | * create a kernel page fault: | ||
355 | */ | ||
356 | #ifdef CONFIG_DEBUG_PAGEALLOC | ||
357 | printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n", | ||
358 | begin, PAGE_ALIGN(end)); | ||
359 | set_memory_np(begin, (end - begin) >> PAGE_SHIFT); | ||
360 | #else | ||
361 | /* | ||
362 | * We just marked the kernel text read only above, now that | ||
363 | * we are going to free part of that, we need to make that | ||
364 | * writeable first. | ||
365 | */ | ||
366 | set_memory_rw(begin, (end - begin) >> PAGE_SHIFT); | ||
367 | |||
368 | printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); | ||
369 | |||
370 | for (; addr < end; addr += PAGE_SIZE) { | ||
371 | ClearPageReserved(virt_to_page(addr)); | ||
372 | init_page_count(virt_to_page(addr)); | ||
373 | memset((void *)(addr & ~(PAGE_SIZE-1)), | ||
374 | POISON_FREE_INITMEM, PAGE_SIZE); | ||
375 | free_page(addr); | ||
376 | totalram_pages++; | ||
377 | } | ||
378 | #endif | ||
379 | } | ||
380 | |||
381 | void free_initmem(void) | ||
382 | { | ||
383 | free_init_pages("unused kernel memory", | ||
384 | (unsigned long)(&__init_begin), | ||
385 | (unsigned long)(&__init_end)); | ||
386 | } | ||
387 | |||
388 | #ifdef CONFIG_BLK_DEV_INITRD | ||
389 | void free_initrd_mem(unsigned long start, unsigned long end) | ||
390 | { | ||
391 | free_init_pages("initrd memory", start, end); | ||
392 | } | ||
393 | #endif | ||