Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * |
3 | * Copyright (C) 1995 Linus Torvalds | |
4 | * | |
5 | * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 | |
6 | */ | |
7 | ||
1da177e4 LT |
8 | #include <linux/module.h> |
9 | #include <linux/signal.h> | |
10 | #include <linux/sched.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/hugetlb.h> | |
19 | #include <linux/swap.h> | |
20 | #include <linux/smp.h> | |
21 | #include <linux/init.h> | |
22 | #include <linux/highmem.h> | |
23 | #include <linux/pagemap.h> | |
6fb14755 | 24 | #include <linux/pfn.h> |
c9cf5528 | 25 | #include <linux/poison.h> |
1da177e4 LT |
26 | #include <linux/bootmem.h> |
27 | #include <linux/slab.h> | |
28 | #include <linux/proc_fs.h> | |
05039b92 | 29 | #include <linux/memory_hotplug.h> |
27d99f7e | 30 | #include <linux/initrd.h> |
55b2355e | 31 | #include <linux/cpumask.h> |
1da177e4 | 32 | |
f832ff18 | 33 | #include <asm/asm.h> |
1da177e4 LT |
34 | #include <asm/processor.h> |
35 | #include <asm/system.h> | |
36 | #include <asm/uaccess.h> | |
37 | #include <asm/pgtable.h> | |
38 | #include <asm/dma.h> | |
39 | #include <asm/fixmap.h> | |
40 | #include <asm/e820.h> | |
41 | #include <asm/apic.h> | |
8550eb99 | 42 | #include <asm/bugs.h> |
1da177e4 LT |
43 | #include <asm/tlb.h> |
44 | #include <asm/tlbflush.h> | |
a5a19c63 | 45 | #include <asm/pgalloc.h> |
1da177e4 | 46 | #include <asm/sections.h> |
b239fb25 | 47 | #include <asm/paravirt.h> |
551889a6 | 48 | #include <asm/setup.h> |
7bfeab9a | 49 | #include <asm/cacheflush.h> |
1da177e4 LT |
50 | |
51 | unsigned int __VMALLOC_RESERVE = 128 << 20; | |
52 | ||
67794292 | 53 | unsigned long max_pfn_mapped; |
7d1116a9 | 54 | |
1da177e4 LT |
55 | DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); |
56 | unsigned long highstart_pfn, highend_pfn; | |
57 | ||
8550eb99 | 58 | static noinline int do_test_wp_bit(void); |
1da177e4 LT |
59 | |
60 | /* | |
61 | * Creates a middle page table and puts a pointer to it in the | |
62 | * given global directory entry. This only returns the gd entry | |
63 | * in non-PAE compilation mode, since the middle layer is folded. | |
64 | */ | |
65 | static pmd_t * __init one_md_table_init(pgd_t *pgd) | |
66 | { | |
67 | pud_t *pud; | |
68 | pmd_t *pmd_table; | |
8550eb99 | 69 | |
1da177e4 | 70 | #ifdef CONFIG_X86_PAE |
b239fb25 JF |
71 | if (!(pgd_val(*pgd) & _PAGE_PRESENT)) { |
72 | pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE); | |
73 | ||
6c435456 | 74 | paravirt_alloc_pd(&init_mm, __pa(pmd_table) >> PAGE_SHIFT); |
b239fb25 JF |
75 | set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT)); |
76 | pud = pud_offset(pgd, 0); | |
8550eb99 | 77 | BUG_ON(pmd_table != pmd_offset(pud, 0)); |
b239fb25 JF |
78 | } |
79 | #endif | |
1da177e4 LT |
80 | pud = pud_offset(pgd, 0); |
81 | pmd_table = pmd_offset(pud, 0); | |
8550eb99 | 82 | |
1da177e4 LT |
83 | return pmd_table; |
84 | } | |
85 | ||
86 | /* | |
87 | * Create a page table and place a pointer to it in a middle page | |
8550eb99 | 88 | * directory entry: |
1da177e4 LT |
89 | */ |
90 | static pte_t * __init one_page_table_init(pmd_t *pmd) | |
91 | { | |
b239fb25 | 92 | if (!(pmd_val(*pmd) & _PAGE_PRESENT)) { |
509a80c4 IM |
93 | pte_t *page_table = NULL; |
94 | ||
95 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
96 | page_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE); | |
97 | #endif | |
8550eb99 | 98 | if (!page_table) { |
509a80c4 IM |
99 | page_table = |
100 | (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE); | |
8550eb99 | 101 | } |
b239fb25 | 102 | |
fdb4c338 | 103 | paravirt_alloc_pt(&init_mm, __pa(page_table) >> PAGE_SHIFT); |
1da177e4 | 104 | set_pmd(pmd, __pmd(__pa(page_table) | _PAGE_TABLE)); |
b239fb25 | 105 | BUG_ON(page_table != pte_offset_kernel(pmd, 0)); |
1da177e4 | 106 | } |
509a80c4 | 107 | |
1da177e4 LT |
108 | return pte_offset_kernel(pmd, 0); |
109 | } | |
110 | ||
111 | /* | |
8550eb99 | 112 | * This function initializes a certain range of kernel virtual memory |
1da177e4 LT |
113 | * with new bootmem page tables, everywhere page tables are missing in |
114 | * the given range. | |
8550eb99 IM |
115 | * |
116 | * NOTE: The pagetables are allocated contiguous on the physical space | |
117 | * so we can cache the place of the first one and move around without | |
1da177e4 LT |
118 | * checking the pgd every time. |
119 | */ | |
8550eb99 IM |
120 | static void __init |
121 | page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base) | |
1da177e4 | 122 | { |
1da177e4 LT |
123 | int pgd_idx, pmd_idx; |
124 | unsigned long vaddr; | |
8550eb99 IM |
125 | pgd_t *pgd; |
126 | pmd_t *pmd; | |
1da177e4 LT |
127 | |
128 | vaddr = start; | |
129 | pgd_idx = pgd_index(vaddr); | |
130 | pmd_idx = pmd_index(vaddr); | |
131 | pgd = pgd_base + pgd_idx; | |
132 | ||
133 | for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd++, pgd_idx++) { | |
b239fb25 JF |
134 | pmd = one_md_table_init(pgd); |
135 | pmd = pmd + pmd_index(vaddr); | |
8550eb99 IM |
136 | for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end); |
137 | pmd++, pmd_idx++) { | |
b239fb25 | 138 | one_page_table_init(pmd); |
1da177e4 LT |
139 | |
140 | vaddr += PMD_SIZE; | |
141 | } | |
142 | pmd_idx = 0; | |
143 | } | |
144 | } | |
145 | ||
146 | static inline int is_kernel_text(unsigned long addr) | |
147 | { | |
148 | if (addr >= PAGE_OFFSET && addr <= (unsigned long)__init_end) | |
149 | return 1; | |
150 | return 0; | |
151 | } | |
152 | ||
153 | /* | |
8550eb99 IM |
154 | * This maps the physical memory to kernel virtual address space, a total |
155 | * of max_low_pfn pages, by creating page tables starting from address | |
156 | * PAGE_OFFSET: | |
1da177e4 LT |
157 | */ |
158 | static void __init kernel_physical_mapping_init(pgd_t *pgd_base) | |
159 | { | |
8550eb99 | 160 | int pgd_idx, pmd_idx, pte_ofs; |
1da177e4 LT |
161 | unsigned long pfn; |
162 | pgd_t *pgd; | |
163 | pmd_t *pmd; | |
164 | pte_t *pte; | |
1da177e4 LT |
165 | |
166 | pgd_idx = pgd_index(PAGE_OFFSET); | |
167 | pgd = pgd_base + pgd_idx; | |
168 | pfn = 0; | |
169 | ||
170 | for (; pgd_idx < PTRS_PER_PGD; pgd++, pgd_idx++) { | |
171 | pmd = one_md_table_init(pgd); | |
172 | if (pfn >= max_low_pfn) | |
173 | continue; | |
8550eb99 | 174 | |
f3f20de8 JF |
175 | for (pmd_idx = 0; |
176 | pmd_idx < PTRS_PER_PMD && pfn < max_low_pfn; | |
177 | pmd++, pmd_idx++) { | |
8550eb99 | 178 | unsigned int addr = pfn * PAGE_SIZE + PAGE_OFFSET; |
1da177e4 | 179 | |
8550eb99 IM |
180 | /* |
181 | * Map with big pages if possible, otherwise | |
182 | * create normal page tables: | |
f5c24a7f AK |
183 | * |
184 | * Don't use a large page for the first 2/4MB of memory | |
185 | * because there are often fixed size MTRRs in there | |
186 | * and overlapping MTRRs into large pages can cause | |
187 | * slowdowns. | |
8550eb99 | 188 | */ |
f5c24a7f | 189 | if (cpu_has_pse && !(pgd_idx == 0 && pmd_idx == 0)) { |
8550eb99 | 190 | unsigned int addr2; |
f3f20de8 JF |
191 | pgprot_t prot = PAGE_KERNEL_LARGE; |
192 | ||
8550eb99 | 193 | addr2 = (pfn + PTRS_PER_PTE-1) * PAGE_SIZE + |
f3f20de8 JF |
194 | PAGE_OFFSET + PAGE_SIZE-1; |
195 | ||
8550eb99 IM |
196 | if (is_kernel_text(addr) || |
197 | is_kernel_text(addr2)) | |
f3f20de8 JF |
198 | prot = PAGE_KERNEL_LARGE_EXEC; |
199 | ||
200 | set_pmd(pmd, pfn_pmd(pfn, prot)); | |
b239fb25 | 201 | |
1da177e4 | 202 | pfn += PTRS_PER_PTE; |
67794292 | 203 | max_pfn_mapped = pfn; |
8550eb99 IM |
204 | continue; |
205 | } | |
206 | pte = one_page_table_init(pmd); | |
1da177e4 | 207 | |
8550eb99 IM |
208 | for (pte_ofs = 0; |
209 | pte_ofs < PTRS_PER_PTE && pfn < max_low_pfn; | |
210 | pte++, pfn++, pte_ofs++, addr += PAGE_SIZE) { | |
211 | pgprot_t prot = PAGE_KERNEL; | |
f3f20de8 | 212 | |
8550eb99 IM |
213 | if (is_kernel_text(addr)) |
214 | prot = PAGE_KERNEL_EXEC; | |
f3f20de8 | 215 | |
8550eb99 | 216 | set_pte(pte, pfn_pte(pfn, prot)); |
1da177e4 | 217 | } |
67794292 | 218 | max_pfn_mapped = pfn; |
1da177e4 LT |
219 | } |
220 | } | |
221 | } | |
222 | ||
223 | static inline int page_kills_ppro(unsigned long pagenr) | |
224 | { | |
225 | if (pagenr >= 0x70000 && pagenr <= 0x7003F) | |
226 | return 1; | |
227 | return 0; | |
228 | } | |
229 | ||
1da177e4 LT |
230 | #ifdef CONFIG_HIGHMEM |
231 | pte_t *kmap_pte; | |
232 | pgprot_t kmap_prot; | |
233 | ||
8550eb99 IM |
234 | static inline pte_t *kmap_get_fixmap_pte(unsigned long vaddr) |
235 | { | |
236 | return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), | |
237 | vaddr), vaddr), vaddr); | |
238 | } | |
1da177e4 LT |
239 | |
240 | static void __init kmap_init(void) | |
241 | { | |
242 | unsigned long kmap_vstart; | |
243 | ||
8550eb99 IM |
244 | /* |
245 | * Cache the first kmap pte: | |
246 | */ | |
1da177e4 LT |
247 | kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN); |
248 | kmap_pte = kmap_get_fixmap_pte(kmap_vstart); | |
249 | ||
250 | kmap_prot = PAGE_KERNEL; | |
251 | } | |
252 | ||
253 | static void __init permanent_kmaps_init(pgd_t *pgd_base) | |
254 | { | |
8550eb99 | 255 | unsigned long vaddr; |
1da177e4 LT |
256 | pgd_t *pgd; |
257 | pud_t *pud; | |
258 | pmd_t *pmd; | |
259 | pte_t *pte; | |
1da177e4 LT |
260 | |
261 | vaddr = PKMAP_BASE; | |
262 | page_table_range_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base); | |
263 | ||
264 | pgd = swapper_pg_dir + pgd_index(vaddr); | |
265 | pud = pud_offset(pgd, vaddr); | |
266 | pmd = pmd_offset(pud, vaddr); | |
267 | pte = pte_offset_kernel(pmd, vaddr); | |
8550eb99 | 268 | pkmap_page_table = pte; |
1da177e4 LT |
269 | } |
270 | ||
c09b4240 | 271 | static void __meminit free_new_highpage(struct page *page) |
05039b92 | 272 | { |
7835e98b | 273 | init_page_count(page); |
05039b92 DH |
274 | __free_page(page); |
275 | totalhigh_pages++; | |
276 | } | |
277 | ||
278 | void __init add_one_highpage_init(struct page *page, int pfn, int bad_ppro) | |
1da177e4 LT |
279 | { |
280 | if (page_is_ram(pfn) && !(bad_ppro && page_kills_ppro(pfn))) { | |
281 | ClearPageReserved(page); | |
05039b92 | 282 | free_new_highpage(page); |
1da177e4 LT |
283 | } else |
284 | SetPageReserved(page); | |
285 | } | |
286 | ||
8550eb99 IM |
287 | static int __meminit |
288 | add_one_highpage_hotplug(struct page *page, unsigned long pfn) | |
05039b92 DH |
289 | { |
290 | free_new_highpage(page); | |
291 | totalram_pages++; | |
292 | #ifdef CONFIG_FLATMEM | |
293 | max_mapnr = max(pfn, max_mapnr); | |
294 | #endif | |
295 | num_physpages++; | |
8550eb99 | 296 | |
05039b92 DH |
297 | return 0; |
298 | } | |
299 | ||
300 | /* | |
301 | * Not currently handling the NUMA case. | |
302 | * Assuming single node and all memory that | |
303 | * has been added dynamically that would be | |
8550eb99 | 304 | * onlined here is in HIGHMEM. |
05039b92 | 305 | */ |
0e0be25d | 306 | void __meminit online_page(struct page *page) |
05039b92 DH |
307 | { |
308 | ClearPageReserved(page); | |
309 | add_one_highpage_hotplug(page, page_to_pfn(page)); | |
310 | } | |
311 | ||
8550eb99 | 312 | #ifndef CONFIG_NUMA |
1da177e4 LT |
313 | static void __init set_highmem_pages_init(int bad_ppro) |
314 | { | |
315 | int pfn; | |
8550eb99 | 316 | |
23be8c7d IM |
317 | for (pfn = highstart_pfn; pfn < highend_pfn; pfn++) { |
318 | /* | |
319 | * Holes under sparsemem might not have no mem_map[]: | |
320 | */ | |
321 | if (pfn_valid(pfn)) | |
322 | add_one_highpage_init(pfn_to_page(pfn), pfn, bad_ppro); | |
323 | } | |
1da177e4 LT |
324 | totalram_pages += totalhigh_pages; |
325 | } | |
8550eb99 | 326 | #endif /* !CONFIG_NUMA */ |
1da177e4 LT |
327 | |
328 | #else | |
8550eb99 IM |
329 | # define kmap_init() do { } while (0) |
330 | # define permanent_kmaps_init(pgd_base) do { } while (0) | |
331 | # define set_highmem_pages_init(bad_ppro) do { } while (0) | |
1da177e4 LT |
332 | #endif /* CONFIG_HIGHMEM */ |
333 | ||
c93c82bb | 334 | pteval_t __PAGE_KERNEL = _PAGE_KERNEL; |
129f6946 | 335 | EXPORT_SYMBOL(__PAGE_KERNEL); |
1da177e4 | 336 | |
8550eb99 | 337 | pteval_t __PAGE_KERNEL_EXEC = _PAGE_KERNEL_EXEC; |
1da177e4 | 338 | |
b239fb25 | 339 | void __init native_pagetable_setup_start(pgd_t *base) |
1da177e4 | 340 | { |
551889a6 IC |
341 | unsigned long pfn, va; |
342 | pgd_t *pgd; | |
343 | pud_t *pud; | |
344 | pmd_t *pmd; | |
345 | pte_t *pte; | |
b239fb25 JF |
346 | |
347 | /* | |
551889a6 IC |
348 | * Remove any mappings which extend past the end of physical |
349 | * memory from the boot time page table: | |
b239fb25 | 350 | */ |
551889a6 IC |
351 | for (pfn = max_low_pfn + 1; pfn < 1<<(32-PAGE_SHIFT); pfn++) { |
352 | va = PAGE_OFFSET + (pfn<<PAGE_SHIFT); | |
353 | pgd = base + pgd_index(va); | |
354 | if (!pgd_present(*pgd)) | |
355 | break; | |
356 | ||
357 | pud = pud_offset(pgd, va); | |
358 | pmd = pmd_offset(pud, va); | |
359 | if (!pmd_present(*pmd)) | |
360 | break; | |
361 | ||
362 | pte = pte_offset_kernel(pmd, va); | |
363 | if (!pte_present(*pte)) | |
364 | break; | |
365 | ||
366 | pte_clear(NULL, va, pte); | |
367 | } | |
6c435456 | 368 | paravirt_alloc_pd(&init_mm, __pa(base) >> PAGE_SHIFT); |
b239fb25 JF |
369 | } |
370 | ||
371 | void __init native_pagetable_setup_done(pgd_t *base) | |
372 | { | |
b239fb25 JF |
373 | } |
374 | ||
375 | /* | |
376 | * Build a proper pagetable for the kernel mappings. Up until this | |
377 | * point, we've been running on some set of pagetables constructed by | |
378 | * the boot process. | |
379 | * | |
380 | * If we're booting on native hardware, this will be a pagetable | |
551889a6 IC |
381 | * constructed in arch/x86/kernel/head_32.S. The root of the |
382 | * pagetable will be swapper_pg_dir. | |
b239fb25 JF |
383 | * |
384 | * If we're booting paravirtualized under a hypervisor, then there are | |
385 | * more options: we may already be running PAE, and the pagetable may | |
386 | * or may not be based in swapper_pg_dir. In any case, | |
387 | * paravirt_pagetable_setup_start() will set up swapper_pg_dir | |
388 | * appropriately for the rest of the initialization to work. | |
389 | * | |
390 | * In general, pagetable_init() assumes that the pagetable may already | |
391 | * be partially populated, and so it avoids stomping on any existing | |
392 | * mappings. | |
393 | */ | |
8550eb99 | 394 | static void __init pagetable_init(void) |
b239fb25 | 395 | { |
b239fb25 | 396 | pgd_t *pgd_base = swapper_pg_dir; |
8550eb99 | 397 | unsigned long vaddr, end; |
b239fb25 JF |
398 | |
399 | paravirt_pagetable_setup_start(pgd_base); | |
1da177e4 LT |
400 | |
401 | /* Enable PSE if available */ | |
b239fb25 | 402 | if (cpu_has_pse) |
1da177e4 | 403 | set_in_cr4(X86_CR4_PSE); |
1da177e4 LT |
404 | |
405 | /* Enable PGE if available */ | |
406 | if (cpu_has_pge) { | |
407 | set_in_cr4(X86_CR4_PGE); | |
408 | __PAGE_KERNEL |= _PAGE_GLOBAL; | |
409 | __PAGE_KERNEL_EXEC |= _PAGE_GLOBAL; | |
410 | } | |
411 | ||
412 | kernel_physical_mapping_init(pgd_base); | |
413 | remap_numa_kva(); | |
414 | ||
415 | /* | |
416 | * Fixed mappings, only the page table structure has to be | |
417 | * created - mappings will be set by set_fixmap(): | |
418 | */ | |
beacfaac | 419 | early_ioremap_clear(); |
1da177e4 | 420 | vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK; |
b239fb25 JF |
421 | end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK; |
422 | page_table_range_init(vaddr, end, pgd_base); | |
beacfaac | 423 | early_ioremap_reset(); |
1da177e4 LT |
424 | |
425 | permanent_kmaps_init(pgd_base); | |
426 | ||
b239fb25 | 427 | paravirt_pagetable_setup_done(pgd_base); |
1da177e4 LT |
428 | } |
429 | ||
a6eb84bc | 430 | #ifdef CONFIG_ACPI_SLEEP |
1da177e4 | 431 | /* |
a6eb84bc | 432 | * ACPI suspend needs this for resume, because things like the intel-agp |
1da177e4 LT |
433 | * driver might have split up a kernel 4MB mapping. |
434 | */ | |
a6eb84bc | 435 | char swsusp_pg_dir[PAGE_SIZE] |
8550eb99 | 436 | __attribute__ ((aligned(PAGE_SIZE))); |
1da177e4 LT |
437 | |
438 | static inline void save_pg_dir(void) | |
439 | { | |
440 | memcpy(swsusp_pg_dir, swapper_pg_dir, PAGE_SIZE); | |
441 | } | |
a6eb84bc | 442 | #else /* !CONFIG_ACPI_SLEEP */ |
1da177e4 LT |
443 | static inline void save_pg_dir(void) |
444 | { | |
445 | } | |
a6eb84bc | 446 | #endif /* !CONFIG_ACPI_SLEEP */ |
1da177e4 | 447 | |
8550eb99 | 448 | void zap_low_mappings(void) |
1da177e4 LT |
449 | { |
450 | int i; | |
451 | ||
452 | save_pg_dir(); | |
453 | ||
454 | /* | |
455 | * Zap initial low-memory mappings. | |
456 | * | |
457 | * Note that "pgd_clear()" doesn't do it for | |
458 | * us, because pgd_clear() is a no-op on i386. | |
459 | */ | |
8550eb99 | 460 | for (i = 0; i < USER_PTRS_PER_PGD; i++) { |
1da177e4 LT |
461 | #ifdef CONFIG_X86_PAE |
462 | set_pgd(swapper_pg_dir+i, __pgd(1 + __pa(empty_zero_page))); | |
463 | #else | |
464 | set_pgd(swapper_pg_dir+i, __pgd(0)); | |
465 | #endif | |
8550eb99 | 466 | } |
1da177e4 LT |
467 | flush_tlb_all(); |
468 | } | |
469 | ||
8550eb99 | 470 | int nx_enabled; |
d5321abe | 471 | |
6fdc05d4 JF |
472 | pteval_t __supported_pte_mask __read_mostly = ~_PAGE_NX; |
473 | EXPORT_SYMBOL_GPL(__supported_pte_mask); | |
474 | ||
d5321abe JB |
475 | #ifdef CONFIG_X86_PAE |
476 | ||
8550eb99 | 477 | static int disable_nx __initdata; |
1da177e4 LT |
478 | |
479 | /* | |
480 | * noexec = on|off | |
481 | * | |
482 | * Control non executable mappings. | |
483 | * | |
484 | * on Enable | |
485 | * off Disable | |
486 | */ | |
1a3f239d | 487 | static int __init noexec_setup(char *str) |
1da177e4 | 488 | { |
1a3f239d RR |
489 | if (!str || !strcmp(str, "on")) { |
490 | if (cpu_has_nx) { | |
491 | __supported_pte_mask |= _PAGE_NX; | |
492 | disable_nx = 0; | |
493 | } | |
8550eb99 IM |
494 | } else { |
495 | if (!strcmp(str, "off")) { | |
496 | disable_nx = 1; | |
497 | __supported_pte_mask &= ~_PAGE_NX; | |
498 | } else { | |
499 | return -EINVAL; | |
500 | } | |
501 | } | |
1a3f239d RR |
502 | |
503 | return 0; | |
1da177e4 | 504 | } |
1a3f239d | 505 | early_param("noexec", noexec_setup); |
1da177e4 | 506 | |
1da177e4 LT |
507 | static void __init set_nx(void) |
508 | { | |
509 | unsigned int v[4], l, h; | |
510 | ||
511 | if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) { | |
512 | cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]); | |
8550eb99 | 513 | |
1da177e4 LT |
514 | if ((v[3] & (1 << 20)) && !disable_nx) { |
515 | rdmsr(MSR_EFER, l, h); | |
516 | l |= EFER_NX; | |
517 | wrmsr(MSR_EFER, l, h); | |
518 | nx_enabled = 1; | |
519 | __supported_pte_mask |= _PAGE_NX; | |
520 | } | |
521 | } | |
522 | } | |
1da177e4 LT |
523 | #endif |
524 | ||
525 | /* | |
526 | * paging_init() sets up the page tables - note that the first 8MB are | |
527 | * already mapped by head.S. | |
528 | * | |
529 | * This routines also unmaps the page at virtual kernel address 0, so | |
530 | * that we can trap those pesky NULL-reference errors in the kernel. | |
531 | */ | |
532 | void __init paging_init(void) | |
533 | { | |
534 | #ifdef CONFIG_X86_PAE | |
535 | set_nx(); | |
536 | if (nx_enabled) | |
d7d119d7 | 537 | printk(KERN_INFO "NX (Execute Disable) protection: active\n"); |
1da177e4 | 538 | #endif |
1da177e4 LT |
539 | pagetable_init(); |
540 | ||
541 | load_cr3(swapper_pg_dir); | |
542 | ||
1da177e4 LT |
543 | __flush_tlb_all(); |
544 | ||
545 | kmap_init(); | |
546 | } | |
547 | ||
548 | /* | |
549 | * Test if the WP bit works in supervisor mode. It isn't supported on 386's | |
550 | * and also on some strange 486's (NexGen etc.). All 586+'s are OK. This | |
551 | * used to involve black magic jumps to work around some nasty CPU bugs, | |
552 | * but fortunately the switch to using exceptions got rid of all that. | |
553 | */ | |
1da177e4 LT |
554 | static void __init test_wp_bit(void) |
555 | { | |
d7d119d7 IM |
556 | printk(KERN_INFO |
557 | "Checking if this processor honours the WP bit even in supervisor mode..."); | |
1da177e4 LT |
558 | |
559 | /* Any page-aligned address will do, the test is non-destructive */ | |
560 | __set_fixmap(FIX_WP_TEST, __pa(&swapper_pg_dir), PAGE_READONLY); | |
561 | boot_cpu_data.wp_works_ok = do_test_wp_bit(); | |
562 | clear_fixmap(FIX_WP_TEST); | |
563 | ||
564 | if (!boot_cpu_data.wp_works_ok) { | |
d7d119d7 | 565 | printk(KERN_CONT "No.\n"); |
1da177e4 | 566 | #ifdef CONFIG_X86_WP_WORKS_OK |
d7d119d7 IM |
567 | panic( |
568 | "This kernel doesn't support CPU's with broken WP. Recompile it for a 386!"); | |
1da177e4 LT |
569 | #endif |
570 | } else { | |
d7d119d7 | 571 | printk(KERN_CONT "Ok.\n"); |
1da177e4 LT |
572 | } |
573 | } | |
574 | ||
8550eb99 | 575 | static struct kcore_list kcore_mem, kcore_vmalloc; |
1da177e4 LT |
576 | |
577 | void __init mem_init(void) | |
578 | { | |
1da177e4 | 579 | int codesize, reservedpages, datasize, initsize; |
8550eb99 | 580 | int tmp, bad_ppro; |
1da177e4 | 581 | |
05b79bdc | 582 | #ifdef CONFIG_FLATMEM |
8d8f3cbe | 583 | BUG_ON(!mem_map); |
1da177e4 | 584 | #endif |
1da177e4 LT |
585 | bad_ppro = ppro_with_ram_bug(); |
586 | ||
587 | #ifdef CONFIG_HIGHMEM | |
588 | /* check that fixmap and pkmap do not overlap */ | |
d7d119d7 IM |
589 | if (PKMAP_BASE + LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) { |
590 | printk(KERN_ERR | |
591 | "fixmap and kmap areas overlap - this will crash\n"); | |
1da177e4 | 592 | printk(KERN_ERR "pkstart: %lxh pkend: %lxh fixstart %lxh\n", |
d7d119d7 IM |
593 | PKMAP_BASE, PKMAP_BASE + LAST_PKMAP*PAGE_SIZE, |
594 | FIXADDR_START); | |
1da177e4 LT |
595 | BUG(); |
596 | } | |
597 | #endif | |
1da177e4 LT |
598 | /* this will put all low memory onto the freelists */ |
599 | totalram_pages += free_all_bootmem(); | |
600 | ||
601 | reservedpages = 0; | |
602 | for (tmp = 0; tmp < max_low_pfn; tmp++) | |
603 | /* | |
8550eb99 | 604 | * Only count reserved RAM pages: |
1da177e4 LT |
605 | */ |
606 | if (page_is_ram(tmp) && PageReserved(pfn_to_page(tmp))) | |
607 | reservedpages++; | |
608 | ||
609 | set_highmem_pages_init(bad_ppro); | |
610 | ||
611 | codesize = (unsigned long) &_etext - (unsigned long) &_text; | |
612 | datasize = (unsigned long) &_edata - (unsigned long) &_etext; | |
613 | initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; | |
614 | ||
8550eb99 IM |
615 | kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT); |
616 | kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, | |
1da177e4 LT |
617 | VMALLOC_END-VMALLOC_START); |
618 | ||
8550eb99 IM |
619 | printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, " |
620 | "%dk reserved, %dk data, %dk init, %ldk highmem)\n", | |
1da177e4 LT |
621 | (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), |
622 | num_physpages << (PAGE_SHIFT-10), | |
623 | codesize >> 10, | |
624 | reservedpages << (PAGE_SHIFT-10), | |
625 | datasize >> 10, | |
626 | initsize >> 10, | |
627 | (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)) | |
628 | ); | |
629 | ||
052e7994 | 630 | #if 1 /* double-sanity-check paranoia */ |
d7d119d7 | 631 | printk(KERN_INFO "virtual kernel memory layout:\n" |
8550eb99 | 632 | " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" |
052e7994 | 633 | #ifdef CONFIG_HIGHMEM |
8550eb99 | 634 | " pkmap : 0x%08lx - 0x%08lx (%4ld kB)\n" |
052e7994 | 635 | #endif |
8550eb99 IM |
636 | " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" |
637 | " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" | |
638 | " .init : 0x%08lx - 0x%08lx (%4ld kB)\n" | |
639 | " .data : 0x%08lx - 0x%08lx (%4ld kB)\n" | |
640 | " .text : 0x%08lx - 0x%08lx (%4ld kB)\n", | |
641 | FIXADDR_START, FIXADDR_TOP, | |
642 | (FIXADDR_TOP - FIXADDR_START) >> 10, | |
052e7994 JF |
643 | |
644 | #ifdef CONFIG_HIGHMEM | |
8550eb99 IM |
645 | PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE, |
646 | (LAST_PKMAP*PAGE_SIZE) >> 10, | |
052e7994 JF |
647 | #endif |
648 | ||
8550eb99 IM |
649 | VMALLOC_START, VMALLOC_END, |
650 | (VMALLOC_END - VMALLOC_START) >> 20, | |
052e7994 | 651 | |
8550eb99 IM |
652 | (unsigned long)__va(0), (unsigned long)high_memory, |
653 | ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20, | |
052e7994 | 654 | |
8550eb99 IM |
655 | (unsigned long)&__init_begin, (unsigned long)&__init_end, |
656 | ((unsigned long)&__init_end - | |
657 | (unsigned long)&__init_begin) >> 10, | |
052e7994 | 658 | |
8550eb99 IM |
659 | (unsigned long)&_etext, (unsigned long)&_edata, |
660 | ((unsigned long)&_edata - (unsigned long)&_etext) >> 10, | |
052e7994 | 661 | |
8550eb99 IM |
662 | (unsigned long)&_text, (unsigned long)&_etext, |
663 | ((unsigned long)&_etext - (unsigned long)&_text) >> 10); | |
052e7994 JF |
664 | |
665 | #ifdef CONFIG_HIGHMEM | |
8550eb99 IM |
666 | BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE > FIXADDR_START); |
667 | BUG_ON(VMALLOC_END > PKMAP_BASE); | |
052e7994 | 668 | #endif |
8550eb99 IM |
669 | BUG_ON(VMALLOC_START > VMALLOC_END); |
670 | BUG_ON((unsigned long)high_memory > VMALLOC_START); | |
052e7994 JF |
671 | #endif /* double-sanity-check paranoia */ |
672 | ||
1da177e4 LT |
673 | if (boot_cpu_data.wp_works_ok < 0) |
674 | test_wp_bit(); | |
675 | ||
76ebd054 TG |
676 | cpa_init(); |
677 | ||
1da177e4 LT |
678 | /* |
679 | * Subtle. SMP is doing it's boot stuff late (because it has to | |
680 | * fork idle threads) - but it also needs low mappings for the | |
681 | * protected-mode entry to work. We zap these entries only after | |
682 | * the WP-bit has been tested. | |
683 | */ | |
684 | #ifndef CONFIG_SMP | |
685 | zap_low_mappings(); | |
686 | #endif | |
687 | } | |
688 | ||
ad8f5797 | 689 | #ifdef CONFIG_MEMORY_HOTPLUG |
bc02af93 | 690 | int arch_add_memory(int nid, u64 start, u64 size) |
05039b92 | 691 | { |
7c7e9425 | 692 | struct pglist_data *pgdata = NODE_DATA(nid); |
776ed98b | 693 | struct zone *zone = pgdata->node_zones + ZONE_HIGHMEM; |
05039b92 DH |
694 | unsigned long start_pfn = start >> PAGE_SHIFT; |
695 | unsigned long nr_pages = size >> PAGE_SHIFT; | |
696 | ||
697 | return __add_pages(zone, start_pfn, nr_pages); | |
698 | } | |
9d99aaa3 | 699 | #endif |
05039b92 | 700 | |
1da177e4 LT |
701 | /* |
702 | * This function cannot be __init, since exceptions don't work in that | |
703 | * section. Put this after the callers, so that it cannot be inlined. | |
704 | */ | |
8550eb99 | 705 | static noinline int do_test_wp_bit(void) |
1da177e4 LT |
706 | { |
707 | char tmp_reg; | |
708 | int flag; | |
709 | ||
710 | __asm__ __volatile__( | |
8550eb99 IM |
711 | " movb %0, %1 \n" |
712 | "1: movb %1, %0 \n" | |
713 | " xorl %2, %2 \n" | |
1da177e4 | 714 | "2: \n" |
f832ff18 | 715 | _ASM_EXTABLE(1b,2b) |
1da177e4 LT |
716 | :"=m" (*(char *)fix_to_virt(FIX_WP_TEST)), |
717 | "=q" (tmp_reg), | |
718 | "=r" (flag) | |
719 | :"2" (1) | |
720 | :"memory"); | |
8550eb99 | 721 | |
1da177e4 LT |
722 | return flag; |
723 | } | |
724 | ||
63aaf308 | 725 | #ifdef CONFIG_DEBUG_RODATA |
edeed305 AV |
726 | const int rodata_test_data = 0xC3; |
727 | EXPORT_SYMBOL_GPL(rodata_test_data); | |
63aaf308 | 728 | |
63aaf308 AV |
729 | void mark_rodata_ro(void) |
730 | { | |
6fb14755 JB |
731 | unsigned long start = PFN_ALIGN(_text); |
732 | unsigned long size = PFN_ALIGN(_etext) - start; | |
63aaf308 | 733 | |
4e4eee0e MD |
734 | set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT); |
735 | printk(KERN_INFO "Write protecting the kernel text: %luk\n", | |
736 | size >> 10); | |
0c42f392 AK |
737 | |
738 | #ifdef CONFIG_CPA_DEBUG | |
4e4eee0e MD |
739 | printk(KERN_INFO "Testing CPA: Reverting %lx-%lx\n", |
740 | start, start+size); | |
741 | set_pages_rw(virt_to_page(start), size>>PAGE_SHIFT); | |
0c42f392 | 742 | |
4e4eee0e MD |
743 | printk(KERN_INFO "Testing CPA: write protecting again\n"); |
744 | set_pages_ro(virt_to_page(start), size>>PAGE_SHIFT); | |
602033ed | 745 | #endif |
6fb14755 JB |
746 | start += size; |
747 | size = (unsigned long)__end_rodata - start; | |
6d238cc4 | 748 | set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT); |
d7d119d7 IM |
749 | printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", |
750 | size >> 10); | |
edeed305 | 751 | rodata_test(); |
63aaf308 | 752 | |
0c42f392 | 753 | #ifdef CONFIG_CPA_DEBUG |
d7d119d7 | 754 | printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, start + size); |
6d238cc4 | 755 | set_pages_rw(virt_to_page(start), size >> PAGE_SHIFT); |
0c42f392 | 756 | |
d7d119d7 | 757 | printk(KERN_INFO "Testing CPA: write protecting again\n"); |
6d238cc4 | 758 | set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT); |
0c42f392 | 759 | #endif |
63aaf308 AV |
760 | } |
761 | #endif | |
762 | ||
9a0b5817 GH |
763 | void free_init_pages(char *what, unsigned long begin, unsigned long end) |
764 | { | |
ee01f112 IM |
765 | #ifdef CONFIG_DEBUG_PAGEALLOC |
766 | /* | |
767 | * If debugging page accesses then do not free this memory but | |
768 | * mark them not present - any buggy init-section access will | |
769 | * create a kernel page fault: | |
770 | */ | |
771 | printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n", | |
772 | begin, PAGE_ALIGN(end)); | |
773 | set_memory_np(begin, (end - begin) >> PAGE_SHIFT); | |
774 | #else | |
86f03989 IM |
775 | unsigned long addr; |
776 | ||
3c1df68b AV |
777 | /* |
778 | * We just marked the kernel text read only above, now that | |
779 | * we are going to free part of that, we need to make that | |
780 | * writeable first. | |
781 | */ | |
782 | set_memory_rw(begin, (end - begin) >> PAGE_SHIFT); | |
783 | ||
9a0b5817 | 784 | for (addr = begin; addr < end; addr += PAGE_SIZE) { |
e3ebadd9 LT |
785 | ClearPageReserved(virt_to_page(addr)); |
786 | init_page_count(virt_to_page(addr)); | |
787 | memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE); | |
788 | free_page(addr); | |
9a0b5817 GH |
789 | totalram_pages++; |
790 | } | |
6fb14755 | 791 | printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); |
ee01f112 | 792 | #endif |
9a0b5817 GH |
793 | } |
794 | ||
795 | void free_initmem(void) | |
796 | { | |
797 | free_init_pages("unused kernel memory", | |
e3ebadd9 LT |
798 | (unsigned long)(&__init_begin), |
799 | (unsigned long)(&__init_end)); | |
9a0b5817 | 800 | } |
63aaf308 | 801 | |
1da177e4 LT |
802 | #ifdef CONFIG_BLK_DEV_INITRD |
803 | void free_initrd_mem(unsigned long start, unsigned long end) | |
804 | { | |
e3ebadd9 | 805 | free_init_pages("initrd memory", start, end); |
1da177e4 LT |
806 | } |
807 | #endif |