vdso.c 21 KB

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  1. /*
  2. * Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
  3. * <benh@kernel.crashing.org>
  4. *
  5. * This program is free software; you can redistribute it and/or
  6. * modify it under the terms of the GNU General Public License
  7. * as published by the Free Software Foundation; either version
  8. * 2 of the License, or (at your option) any later version.
  9. */
  10. #include <linux/errno.h>
  11. #include <linux/sched.h>
  12. #include <linux/kernel.h>
  13. #include <linux/mm.h>
  14. #include <linux/smp.h>
  15. #include <linux/stddef.h>
  16. #include <linux/unistd.h>
  17. #include <linux/slab.h>
  18. #include <linux/user.h>
  19. #include <linux/elf.h>
  20. #include <linux/security.h>
  21. #include <linux/bootmem.h>
  22. #include <linux/memblock.h>
  23. #include <asm/pgtable.h>
  24. #include <asm/processor.h>
  25. #include <asm/mmu.h>
  26. #include <asm/mmu_context.h>
  27. #include <asm/prom.h>
  28. #include <asm/machdep.h>
  29. #include <asm/cputable.h>
  30. #include <asm/sections.h>
  31. #include <asm/firmware.h>
  32. #include <asm/vdso.h>
  33. #include <asm/vdso_datapage.h>
  34. #include "setup.h"
  35. #undef DEBUG
  36. #ifdef DEBUG
  37. #define DBG(fmt...) printk(fmt)
  38. #else
  39. #define DBG(fmt...)
  40. #endif
  41. /* Max supported size for symbol names */
  42. #define MAX_SYMNAME 64
  43. /* The alignment of the vDSO */
  44. #define VDSO_ALIGNMENT (1 << 16)
  45. extern char vdso32_start, vdso32_end;
  46. static void *vdso32_kbase = &vdso32_start;
  47. static unsigned int vdso32_pages;
  48. static struct page **vdso32_pagelist;
  49. unsigned long vdso32_sigtramp;
  50. unsigned long vdso32_rt_sigtramp;
  51. #ifdef CONFIG_PPC64
  52. extern char vdso64_start, vdso64_end;
  53. static void *vdso64_kbase = &vdso64_start;
  54. static unsigned int vdso64_pages;
  55. static struct page **vdso64_pagelist;
  56. unsigned long vdso64_rt_sigtramp;
  57. #endif /* CONFIG_PPC64 */
  58. static int vdso_ready;
  59. /*
  60. * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  61. * Once the early boot kernel code no longer needs to muck around
  62. * with it, it will become dynamically allocated
  63. */
  64. static union {
  65. struct vdso_data data;
  66. u8 page[PAGE_SIZE];
  67. } vdso_data_store __page_aligned_data;
  68. struct vdso_data *vdso_data = &vdso_data_store.data;
  69. /* Format of the patch table */
  70. struct vdso_patch_def
  71. {
  72. unsigned long ftr_mask, ftr_value;
  73. const char *gen_name;
  74. const char *fix_name;
  75. };
  76. /* Table of functions to patch based on the CPU type/revision
  77. *
  78. * Currently, we only change sync_dicache to do nothing on processors
  79. * with a coherent icache
  80. */
  81. static struct vdso_patch_def vdso_patches[] = {
  82. {
  83. CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  84. "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  85. },
  86. {
  87. CPU_FTR_USE_TB, 0,
  88. "__kernel_gettimeofday", NULL
  89. },
  90. {
  91. CPU_FTR_USE_TB, 0,
  92. "__kernel_clock_gettime", NULL
  93. },
  94. {
  95. CPU_FTR_USE_TB, 0,
  96. "__kernel_clock_getres", NULL
  97. },
  98. {
  99. CPU_FTR_USE_TB, 0,
  100. "__kernel_get_tbfreq", NULL
  101. },
  102. {
  103. CPU_FTR_USE_TB, 0,
  104. "__kernel_time", NULL
  105. },
  106. };
  107. /*
  108. * Some infos carried around for each of them during parsing at
  109. * boot time.
  110. */
  111. struct lib32_elfinfo
  112. {
  113. Elf32_Ehdr *hdr; /* ptr to ELF */
  114. Elf32_Sym *dynsym; /* ptr to .dynsym section */
  115. unsigned long dynsymsize; /* size of .dynsym section */
  116. char *dynstr; /* ptr to .dynstr section */
  117. unsigned long text; /* offset of .text section in .so */
  118. };
  119. struct lib64_elfinfo
  120. {
  121. Elf64_Ehdr *hdr;
  122. Elf64_Sym *dynsym;
  123. unsigned long dynsymsize;
  124. char *dynstr;
  125. unsigned long text;
  126. };
  127. #ifdef __DEBUG
  128. static void dump_one_vdso_page(struct page *pg, struct page *upg)
  129. {
  130. printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
  131. page_count(pg),
  132. pg->flags);
  133. if (upg && !IS_ERR(upg) /* && pg != upg*/) {
  134. printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
  135. << PAGE_SHIFT),
  136. page_count(upg),
  137. upg->flags);
  138. }
  139. printk("\n");
  140. }
  141. static void dump_vdso_pages(struct vm_area_struct * vma)
  142. {
  143. int i;
  144. if (!vma || is_32bit_task()) {
  145. printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
  146. for (i=0; i<vdso32_pages; i++) {
  147. struct page *pg = virt_to_page(vdso32_kbase +
  148. i*PAGE_SIZE);
  149. struct page *upg = (vma && vma->vm_mm) ?
  150. follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
  151. : NULL;
  152. dump_one_vdso_page(pg, upg);
  153. }
  154. }
  155. if (!vma || !is_32bit_task()) {
  156. printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
  157. for (i=0; i<vdso64_pages; i++) {
  158. struct page *pg = virt_to_page(vdso64_kbase +
  159. i*PAGE_SIZE);
  160. struct page *upg = (vma && vma->vm_mm) ?
  161. follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
  162. : NULL;
  163. dump_one_vdso_page(pg, upg);
  164. }
  165. }
  166. }
  167. #endif /* DEBUG */
  168. /*
  169. * This is called from binfmt_elf, we create the special vma for the
  170. * vDSO and insert it into the mm struct tree
  171. */
  172. int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
  173. {
  174. struct mm_struct *mm = current->mm;
  175. struct page **vdso_pagelist;
  176. unsigned long vdso_pages;
  177. unsigned long vdso_base;
  178. int rc;
  179. if (!vdso_ready)
  180. return 0;
  181. #ifdef CONFIG_PPC64
  182. if (is_32bit_task()) {
  183. vdso_pagelist = vdso32_pagelist;
  184. vdso_pages = vdso32_pages;
  185. vdso_base = VDSO32_MBASE;
  186. } else {
  187. vdso_pagelist = vdso64_pagelist;
  188. vdso_pages = vdso64_pages;
  189. /*
  190. * On 64bit we don't have a preferred map address. This
  191. * allows get_unmapped_area to find an area near other mmaps
  192. * and most likely share a SLB entry.
  193. */
  194. vdso_base = 0;
  195. }
  196. #else
  197. vdso_pagelist = vdso32_pagelist;
  198. vdso_pages = vdso32_pages;
  199. vdso_base = VDSO32_MBASE;
  200. #endif
  201. current->mm->context.vdso_base = 0;
  202. /* vDSO has a problem and was disabled, just don't "enable" it for the
  203. * process
  204. */
  205. if (vdso_pages == 0)
  206. return 0;
  207. /* Add a page to the vdso size for the data page */
  208. vdso_pages ++;
  209. /*
  210. * pick a base address for the vDSO in process space. We try to put it
  211. * at vdso_base which is the "natural" base for it, but we might fail
  212. * and end up putting it elsewhere.
  213. * Add enough to the size so that the result can be aligned.
  214. */
  215. down_write(&mm->mmap_sem);
  216. vdso_base = get_unmapped_area(NULL, vdso_base,
  217. (vdso_pages << PAGE_SHIFT) +
  218. ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
  219. 0, 0);
  220. if (IS_ERR_VALUE(vdso_base)) {
  221. rc = vdso_base;
  222. goto fail_mmapsem;
  223. }
  224. /* Add required alignment. */
  225. vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
  226. /*
  227. * Put vDSO base into mm struct. We need to do this before calling
  228. * install_special_mapping or the perf counter mmap tracking code
  229. * will fail to recognise it as a vDSO (since arch_vma_name fails).
  230. */
  231. current->mm->context.vdso_base = vdso_base;
  232. /*
  233. * our vma flags don't have VM_WRITE so by default, the process isn't
  234. * allowed to write those pages.
  235. * gdb can break that with ptrace interface, and thus trigger COW on
  236. * those pages but it's then your responsibility to never do that on
  237. * the "data" page of the vDSO or you'll stop getting kernel updates
  238. * and your nice userland gettimeofday will be totally dead.
  239. * It's fine to use that for setting breakpoints in the vDSO code
  240. * pages though.
  241. */
  242. rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
  243. VM_READ|VM_EXEC|
  244. VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
  245. vdso_pagelist);
  246. if (rc) {
  247. current->mm->context.vdso_base = 0;
  248. goto fail_mmapsem;
  249. }
  250. up_write(&mm->mmap_sem);
  251. return 0;
  252. fail_mmapsem:
  253. up_write(&mm->mmap_sem);
  254. return rc;
  255. }
  256. const char *arch_vma_name(struct vm_area_struct *vma)
  257. {
  258. if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
  259. return "[vdso]";
  260. return NULL;
  261. }
  262. static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
  263. unsigned long *size)
  264. {
  265. Elf32_Shdr *sechdrs;
  266. unsigned int i;
  267. char *secnames;
  268. /* Grab section headers and strings so we can tell who is who */
  269. sechdrs = (void *)ehdr + ehdr->e_shoff;
  270. secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
  271. /* Find the section they want */
  272. for (i = 1; i < ehdr->e_shnum; i++) {
  273. if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
  274. if (size)
  275. *size = sechdrs[i].sh_size;
  276. return (void *)ehdr + sechdrs[i].sh_offset;
  277. }
  278. }
  279. *size = 0;
  280. return NULL;
  281. }
  282. static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
  283. const char *symname)
  284. {
  285. unsigned int i;
  286. char name[MAX_SYMNAME], *c;
  287. for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
  288. if (lib->dynsym[i].st_name == 0)
  289. continue;
  290. strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
  291. MAX_SYMNAME);
  292. c = strchr(name, '@');
  293. if (c)
  294. *c = 0;
  295. if (strcmp(symname, name) == 0)
  296. return &lib->dynsym[i];
  297. }
  298. return NULL;
  299. }
  300. /* Note that we assume the section is .text and the symbol is relative to
  301. * the library base
  302. */
  303. static unsigned long __init find_function32(struct lib32_elfinfo *lib,
  304. const char *symname)
  305. {
  306. Elf32_Sym *sym = find_symbol32(lib, symname);
  307. if (sym == NULL) {
  308. printk(KERN_WARNING "vDSO32: function %s not found !\n",
  309. symname);
  310. return 0;
  311. }
  312. return sym->st_value - VDSO32_LBASE;
  313. }
  314. static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
  315. struct lib64_elfinfo *v64,
  316. const char *orig, const char *fix)
  317. {
  318. Elf32_Sym *sym32_gen, *sym32_fix;
  319. sym32_gen = find_symbol32(v32, orig);
  320. if (sym32_gen == NULL) {
  321. printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
  322. return -1;
  323. }
  324. if (fix == NULL) {
  325. sym32_gen->st_name = 0;
  326. return 0;
  327. }
  328. sym32_fix = find_symbol32(v32, fix);
  329. if (sym32_fix == NULL) {
  330. printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
  331. return -1;
  332. }
  333. sym32_gen->st_value = sym32_fix->st_value;
  334. sym32_gen->st_size = sym32_fix->st_size;
  335. sym32_gen->st_info = sym32_fix->st_info;
  336. sym32_gen->st_other = sym32_fix->st_other;
  337. sym32_gen->st_shndx = sym32_fix->st_shndx;
  338. return 0;
  339. }
  340. #ifdef CONFIG_PPC64
  341. static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
  342. unsigned long *size)
  343. {
  344. Elf64_Shdr *sechdrs;
  345. unsigned int i;
  346. char *secnames;
  347. /* Grab section headers and strings so we can tell who is who */
  348. sechdrs = (void *)ehdr + ehdr->e_shoff;
  349. secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
  350. /* Find the section they want */
  351. for (i = 1; i < ehdr->e_shnum; i++) {
  352. if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
  353. if (size)
  354. *size = sechdrs[i].sh_size;
  355. return (void *)ehdr + sechdrs[i].sh_offset;
  356. }
  357. }
  358. if (size)
  359. *size = 0;
  360. return NULL;
  361. }
  362. static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
  363. const char *symname)
  364. {
  365. unsigned int i;
  366. char name[MAX_SYMNAME], *c;
  367. for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
  368. if (lib->dynsym[i].st_name == 0)
  369. continue;
  370. strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
  371. MAX_SYMNAME);
  372. c = strchr(name, '@');
  373. if (c)
  374. *c = 0;
  375. if (strcmp(symname, name) == 0)
  376. return &lib->dynsym[i];
  377. }
  378. return NULL;
  379. }
  380. /* Note that we assume the section is .text and the symbol is relative to
  381. * the library base
  382. */
  383. static unsigned long __init find_function64(struct lib64_elfinfo *lib,
  384. const char *symname)
  385. {
  386. Elf64_Sym *sym = find_symbol64(lib, symname);
  387. if (sym == NULL) {
  388. printk(KERN_WARNING "vDSO64: function %s not found !\n",
  389. symname);
  390. return 0;
  391. }
  392. #ifdef VDS64_HAS_DESCRIPTORS
  393. return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
  394. VDSO64_LBASE;
  395. #else
  396. return sym->st_value - VDSO64_LBASE;
  397. #endif
  398. }
  399. static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
  400. struct lib64_elfinfo *v64,
  401. const char *orig, const char *fix)
  402. {
  403. Elf64_Sym *sym64_gen, *sym64_fix;
  404. sym64_gen = find_symbol64(v64, orig);
  405. if (sym64_gen == NULL) {
  406. printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
  407. return -1;
  408. }
  409. if (fix == NULL) {
  410. sym64_gen->st_name = 0;
  411. return 0;
  412. }
  413. sym64_fix = find_symbol64(v64, fix);
  414. if (sym64_fix == NULL) {
  415. printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
  416. return -1;
  417. }
  418. sym64_gen->st_value = sym64_fix->st_value;
  419. sym64_gen->st_size = sym64_fix->st_size;
  420. sym64_gen->st_info = sym64_fix->st_info;
  421. sym64_gen->st_other = sym64_fix->st_other;
  422. sym64_gen->st_shndx = sym64_fix->st_shndx;
  423. return 0;
  424. }
  425. #endif /* CONFIG_PPC64 */
  426. static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
  427. struct lib64_elfinfo *v64)
  428. {
  429. void *sect;
  430. /*
  431. * Locate symbol tables & text section
  432. */
  433. v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
  434. v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
  435. if (v32->dynsym == NULL || v32->dynstr == NULL) {
  436. printk(KERN_ERR "vDSO32: required symbol section not found\n");
  437. return -1;
  438. }
  439. sect = find_section32(v32->hdr, ".text", NULL);
  440. if (sect == NULL) {
  441. printk(KERN_ERR "vDSO32: the .text section was not found\n");
  442. return -1;
  443. }
  444. v32->text = sect - vdso32_kbase;
  445. #ifdef CONFIG_PPC64
  446. v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
  447. v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
  448. if (v64->dynsym == NULL || v64->dynstr == NULL) {
  449. printk(KERN_ERR "vDSO64: required symbol section not found\n");
  450. return -1;
  451. }
  452. sect = find_section64(v64->hdr, ".text", NULL);
  453. if (sect == NULL) {
  454. printk(KERN_ERR "vDSO64: the .text section was not found\n");
  455. return -1;
  456. }
  457. v64->text = sect - vdso64_kbase;
  458. #endif /* CONFIG_PPC64 */
  459. return 0;
  460. }
  461. static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
  462. struct lib64_elfinfo *v64)
  463. {
  464. /*
  465. * Find signal trampolines
  466. */
  467. #ifdef CONFIG_PPC64
  468. vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
  469. #endif
  470. vdso32_sigtramp = find_function32(v32, "__kernel_sigtramp32");
  471. vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
  472. }
  473. static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
  474. struct lib64_elfinfo *v64)
  475. {
  476. Elf32_Sym *sym32;
  477. #ifdef CONFIG_PPC64
  478. Elf64_Sym *sym64;
  479. sym64 = find_symbol64(v64, "__kernel_datapage_offset");
  480. if (sym64 == NULL) {
  481. printk(KERN_ERR "vDSO64: Can't find symbol "
  482. "__kernel_datapage_offset !\n");
  483. return -1;
  484. }
  485. *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
  486. (vdso64_pages << PAGE_SHIFT) -
  487. (sym64->st_value - VDSO64_LBASE);
  488. #endif /* CONFIG_PPC64 */
  489. sym32 = find_symbol32(v32, "__kernel_datapage_offset");
  490. if (sym32 == NULL) {
  491. printk(KERN_ERR "vDSO32: Can't find symbol "
  492. "__kernel_datapage_offset !\n");
  493. return -1;
  494. }
  495. *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
  496. (vdso32_pages << PAGE_SHIFT) -
  497. (sym32->st_value - VDSO32_LBASE);
  498. return 0;
  499. }
  500. static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
  501. struct lib64_elfinfo *v64)
  502. {
  503. void *start32;
  504. unsigned long size32;
  505. #ifdef CONFIG_PPC64
  506. void *start64;
  507. unsigned long size64;
  508. start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
  509. if (start64)
  510. do_feature_fixups(cur_cpu_spec->cpu_features,
  511. start64, start64 + size64);
  512. start64 = find_section64(v64->hdr, "__mmu_ftr_fixup", &size64);
  513. if (start64)
  514. do_feature_fixups(cur_cpu_spec->mmu_features,
  515. start64, start64 + size64);
  516. start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
  517. if (start64)
  518. do_feature_fixups(powerpc_firmware_features,
  519. start64, start64 + size64);
  520. start64 = find_section64(v64->hdr, "__lwsync_fixup", &size64);
  521. if (start64)
  522. do_lwsync_fixups(cur_cpu_spec->cpu_features,
  523. start64, start64 + size64);
  524. #endif /* CONFIG_PPC64 */
  525. start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
  526. if (start32)
  527. do_feature_fixups(cur_cpu_spec->cpu_features,
  528. start32, start32 + size32);
  529. start32 = find_section32(v32->hdr, "__mmu_ftr_fixup", &size32);
  530. if (start32)
  531. do_feature_fixups(cur_cpu_spec->mmu_features,
  532. start32, start32 + size32);
  533. #ifdef CONFIG_PPC64
  534. start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
  535. if (start32)
  536. do_feature_fixups(powerpc_firmware_features,
  537. start32, start32 + size32);
  538. #endif /* CONFIG_PPC64 */
  539. start32 = find_section32(v32->hdr, "__lwsync_fixup", &size32);
  540. if (start32)
  541. do_lwsync_fixups(cur_cpu_spec->cpu_features,
  542. start32, start32 + size32);
  543. return 0;
  544. }
  545. static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
  546. struct lib64_elfinfo *v64)
  547. {
  548. int i;
  549. for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
  550. struct vdso_patch_def *patch = &vdso_patches[i];
  551. int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
  552. == patch->ftr_value;
  553. if (!match)
  554. continue;
  555. DBG("replacing %s with %s...\n", patch->gen_name,
  556. patch->fix_name ? "NONE" : patch->fix_name);
  557. /*
  558. * Patch the 32 bits and 64 bits symbols. Note that we do not
  559. * patch the "." symbol on 64 bits.
  560. * It would be easy to do, but doesn't seem to be necessary,
  561. * patching the OPD symbol is enough.
  562. */
  563. vdso_do_func_patch32(v32, v64, patch->gen_name,
  564. patch->fix_name);
  565. #ifdef CONFIG_PPC64
  566. vdso_do_func_patch64(v32, v64, patch->gen_name,
  567. patch->fix_name);
  568. #endif /* CONFIG_PPC64 */
  569. }
  570. return 0;
  571. }
  572. static __init int vdso_setup(void)
  573. {
  574. struct lib32_elfinfo v32;
  575. struct lib64_elfinfo v64;
  576. v32.hdr = vdso32_kbase;
  577. #ifdef CONFIG_PPC64
  578. v64.hdr = vdso64_kbase;
  579. #endif
  580. if (vdso_do_find_sections(&v32, &v64))
  581. return -1;
  582. if (vdso_fixup_datapage(&v32, &v64))
  583. return -1;
  584. if (vdso_fixup_features(&v32, &v64))
  585. return -1;
  586. if (vdso_fixup_alt_funcs(&v32, &v64))
  587. return -1;
  588. vdso_setup_trampolines(&v32, &v64);
  589. return 0;
  590. }
  591. /*
  592. * Called from setup_arch to initialize the bitmap of available
  593. * syscalls in the systemcfg page
  594. */
  595. static void __init vdso_setup_syscall_map(void)
  596. {
  597. unsigned int i;
  598. extern unsigned long *sys_call_table;
  599. extern unsigned long sys_ni_syscall;
  600. for (i = 0; i < __NR_syscalls; i++) {
  601. #ifdef CONFIG_PPC64
  602. if (sys_call_table[i*2] != sys_ni_syscall)
  603. vdso_data->syscall_map_64[i >> 5] |=
  604. 0x80000000UL >> (i & 0x1f);
  605. if (sys_call_table[i*2+1] != sys_ni_syscall)
  606. vdso_data->syscall_map_32[i >> 5] |=
  607. 0x80000000UL >> (i & 0x1f);
  608. #else /* CONFIG_PPC64 */
  609. if (sys_call_table[i] != sys_ni_syscall)
  610. vdso_data->syscall_map_32[i >> 5] |=
  611. 0x80000000UL >> (i & 0x1f);
  612. #endif /* CONFIG_PPC64 */
  613. }
  614. }
  615. #ifdef CONFIG_PPC64
  616. int vdso_getcpu_init(void)
  617. {
  618. unsigned long cpu, node, val;
  619. /*
  620. * SPRG3 contains the CPU in the bottom 16 bits and the NUMA node in
  621. * the next 16 bits. The VDSO uses this to implement getcpu().
  622. */
  623. cpu = get_cpu();
  624. WARN_ON_ONCE(cpu > 0xffff);
  625. node = cpu_to_node(cpu);
  626. WARN_ON_ONCE(node > 0xffff);
  627. val = (cpu & 0xfff) | ((node & 0xffff) << 16);
  628. mtspr(SPRN_SPRG3, val);
  629. get_paca()->sprg3 = val;
  630. put_cpu();
  631. return 0;
  632. }
  633. /* We need to call this before SMP init */
  634. early_initcall(vdso_getcpu_init);
  635. #endif
  636. static int __init vdso_init(void)
  637. {
  638. int i;
  639. #ifdef CONFIG_PPC64
  640. /*
  641. * Fill up the "systemcfg" stuff for backward compatibility
  642. */
  643. strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
  644. vdso_data->version.major = SYSTEMCFG_MAJOR;
  645. vdso_data->version.minor = SYSTEMCFG_MINOR;
  646. vdso_data->processor = mfspr(SPRN_PVR);
  647. /*
  648. * Fake the old platform number for pSeries and add
  649. * in LPAR bit if necessary
  650. */
  651. vdso_data->platform = 0x100;
  652. if (firmware_has_feature(FW_FEATURE_LPAR))
  653. vdso_data->platform |= 1;
  654. vdso_data->physicalMemorySize = memblock_phys_mem_size();
  655. vdso_data->dcache_size = ppc64_caches.dsize;
  656. vdso_data->dcache_line_size = ppc64_caches.dline_size;
  657. vdso_data->icache_size = ppc64_caches.isize;
  658. vdso_data->icache_line_size = ppc64_caches.iline_size;
  659. /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
  660. vdso_data->dcache_block_size = ppc64_caches.dline_size;
  661. vdso_data->icache_block_size = ppc64_caches.iline_size;
  662. vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
  663. vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
  664. /*
  665. * Calculate the size of the 64 bits vDSO
  666. */
  667. vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
  668. DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
  669. #else
  670. vdso_data->dcache_block_size = L1_CACHE_BYTES;
  671. vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
  672. vdso_data->icache_block_size = L1_CACHE_BYTES;
  673. vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
  674. #endif /* CONFIG_PPC64 */
  675. /*
  676. * Calculate the size of the 32 bits vDSO
  677. */
  678. vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
  679. DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
  680. /*
  681. * Setup the syscall map in the vDOS
  682. */
  683. vdso_setup_syscall_map();
  684. /*
  685. * Initialize the vDSO images in memory, that is do necessary
  686. * fixups of vDSO symbols, locate trampolines, etc...
  687. */
  688. if (vdso_setup()) {
  689. printk(KERN_ERR "vDSO setup failure, not enabled !\n");
  690. vdso32_pages = 0;
  691. #ifdef CONFIG_PPC64
  692. vdso64_pages = 0;
  693. #endif
  694. return 0;
  695. }
  696. /* Make sure pages are in the correct state */
  697. vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
  698. GFP_KERNEL);
  699. BUG_ON(vdso32_pagelist == NULL);
  700. for (i = 0; i < vdso32_pages; i++) {
  701. struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
  702. ClearPageReserved(pg);
  703. get_page(pg);
  704. vdso32_pagelist[i] = pg;
  705. }
  706. vdso32_pagelist[i++] = virt_to_page(vdso_data);
  707. vdso32_pagelist[i] = NULL;
  708. #ifdef CONFIG_PPC64
  709. vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
  710. GFP_KERNEL);
  711. BUG_ON(vdso64_pagelist == NULL);
  712. for (i = 0; i < vdso64_pages; i++) {
  713. struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
  714. ClearPageReserved(pg);
  715. get_page(pg);
  716. vdso64_pagelist[i] = pg;
  717. }
  718. vdso64_pagelist[i++] = virt_to_page(vdso_data);
  719. vdso64_pagelist[i] = NULL;
  720. #endif /* CONFIG_PPC64 */
  721. get_page(virt_to_page(vdso_data));
  722. smp_wmb();
  723. vdso_ready = 1;
  724. return 0;
  725. }
  726. arch_initcall(vdso_init);
  727. int in_gate_area_no_mm(unsigned long addr)
  728. {
  729. return 0;
  730. }
  731. int in_gate_area(struct mm_struct *mm, unsigned long addr)
  732. {
  733. return 0;
  734. }
  735. struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
  736. {
  737. return NULL;
  738. }