xref: /linux/arch/powerpc/kernel/vdso.c (revision 1f2367a39f17bd553a75e179a747f9b257bc9478)
1 
2 /*
3  *    Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
4  *			 <benh@kernel.crashing.org>
5  *
6  *  This program is free software; you can redistribute it and/or
7  *  modify it under the terms of the GNU General Public License
8  *  as published by the Free Software Foundation; either version
9  *  2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/errno.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/mm.h>
16 #include <linux/smp.h>
17 #include <linux/stddef.h>
18 #include <linux/unistd.h>
19 #include <linux/slab.h>
20 #include <linux/user.h>
21 #include <linux/elf.h>
22 #include <linux/security.h>
23 #include <linux/memblock.h>
24 
25 #include <asm/pgtable.h>
26 #include <asm/processor.h>
27 #include <asm/mmu.h>
28 #include <asm/mmu_context.h>
29 #include <asm/prom.h>
30 #include <asm/machdep.h>
31 #include <asm/cputable.h>
32 #include <asm/sections.h>
33 #include <asm/firmware.h>
34 #include <asm/vdso.h>
35 #include <asm/vdso_datapage.h>
36 #include <asm/setup.h>
37 
38 #undef DEBUG
39 
40 #ifdef DEBUG
41 #define DBG(fmt...) printk(fmt)
42 #else
43 #define DBG(fmt...)
44 #endif
45 
46 /* Max supported size for symbol names */
47 #define MAX_SYMNAME	64
48 
49 /* The alignment of the vDSO */
50 #define VDSO_ALIGNMENT	(1 << 16)
51 
52 static unsigned int vdso32_pages;
53 static void *vdso32_kbase;
54 static struct page **vdso32_pagelist;
55 unsigned long vdso32_sigtramp;
56 unsigned long vdso32_rt_sigtramp;
57 
58 #ifdef CONFIG_VDSO32
59 extern char vdso32_start, vdso32_end;
60 #endif
61 
62 #ifdef CONFIG_PPC64
63 extern char vdso64_start, vdso64_end;
64 static void *vdso64_kbase = &vdso64_start;
65 static unsigned int vdso64_pages;
66 static struct page **vdso64_pagelist;
67 unsigned long vdso64_rt_sigtramp;
68 #endif /* CONFIG_PPC64 */
69 
70 static int vdso_ready;
71 
72 /*
73  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
74  * Once the early boot kernel code no longer needs to muck around
75  * with it, it will become dynamically allocated
76  */
77 static union {
78 	struct vdso_data	data;
79 	u8			page[PAGE_SIZE];
80 } vdso_data_store __page_aligned_data;
81 struct vdso_data *vdso_data = &vdso_data_store.data;
82 
83 /* Format of the patch table */
84 struct vdso_patch_def
85 {
86 	unsigned long	ftr_mask, ftr_value;
87 	const char	*gen_name;
88 	const char	*fix_name;
89 };
90 
91 /* Table of functions to patch based on the CPU type/revision
92  *
93  * Currently, we only change sync_dicache to do nothing on processors
94  * with a coherent icache
95  */
96 static struct vdso_patch_def vdso_patches[] = {
97 	{
98 		CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
99 		"__kernel_sync_dicache", "__kernel_sync_dicache_p5"
100 	},
101 #ifdef CONFIG_PPC32
102 	{
103 		CPU_FTR_USE_RTC, CPU_FTR_USE_RTC,
104 		"__kernel_gettimeofday", NULL
105 	},
106 	{
107 		CPU_FTR_USE_RTC, CPU_FTR_USE_RTC,
108 		"__kernel_clock_gettime", NULL
109 	},
110 	{
111 		CPU_FTR_USE_RTC, CPU_FTR_USE_RTC,
112 		"__kernel_clock_getres", NULL
113 	},
114 	{
115 		CPU_FTR_USE_RTC, CPU_FTR_USE_RTC,
116 		"__kernel_get_tbfreq", NULL
117 	},
118 	{
119 		CPU_FTR_USE_RTC, CPU_FTR_USE_RTC,
120 		"__kernel_time", NULL
121 	},
122 #endif
123 };
124 
125 /*
126  * Some infos carried around for each of them during parsing at
127  * boot time.
128  */
129 struct lib32_elfinfo
130 {
131 	Elf32_Ehdr	*hdr;		/* ptr to ELF */
132 	Elf32_Sym	*dynsym;	/* ptr to .dynsym section */
133 	unsigned long	dynsymsize;	/* size of .dynsym section */
134 	char		*dynstr;	/* ptr to .dynstr section */
135 	unsigned long	text;		/* offset of .text section in .so */
136 };
137 
138 struct lib64_elfinfo
139 {
140 	Elf64_Ehdr	*hdr;
141 	Elf64_Sym	*dynsym;
142 	unsigned long	dynsymsize;
143 	char		*dynstr;
144 	unsigned long	text;
145 };
146 
147 
148 /*
149  * This is called from binfmt_elf, we create the special vma for the
150  * vDSO and insert it into the mm struct tree
151  */
152 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
153 {
154 	struct mm_struct *mm = current->mm;
155 	struct page **vdso_pagelist;
156 	unsigned long vdso_pages;
157 	unsigned long vdso_base;
158 	int rc;
159 
160 	if (!vdso_ready)
161 		return 0;
162 
163 #ifdef CONFIG_PPC64
164 	if (is_32bit_task()) {
165 		vdso_pagelist = vdso32_pagelist;
166 		vdso_pages = vdso32_pages;
167 		vdso_base = VDSO32_MBASE;
168 	} else {
169 		vdso_pagelist = vdso64_pagelist;
170 		vdso_pages = vdso64_pages;
171 		/*
172 		 * On 64bit we don't have a preferred map address. This
173 		 * allows get_unmapped_area to find an area near other mmaps
174 		 * and most likely share a SLB entry.
175 		 */
176 		vdso_base = 0;
177 	}
178 #else
179 	vdso_pagelist = vdso32_pagelist;
180 	vdso_pages = vdso32_pages;
181 	vdso_base = VDSO32_MBASE;
182 #endif
183 
184 	current->mm->context.vdso_base = 0;
185 
186 	/* vDSO has a problem and was disabled, just don't "enable" it for the
187 	 * process
188 	 */
189 	if (vdso_pages == 0)
190 		return 0;
191 	/* Add a page to the vdso size for the data page */
192 	vdso_pages ++;
193 
194 	/*
195 	 * pick a base address for the vDSO in process space. We try to put it
196 	 * at vdso_base which is the "natural" base for it, but we might fail
197 	 * and end up putting it elsewhere.
198 	 * Add enough to the size so that the result can be aligned.
199 	 */
200 	if (down_write_killable(&mm->mmap_sem))
201 		return -EINTR;
202 	vdso_base = get_unmapped_area(NULL, vdso_base,
203 				      (vdso_pages << PAGE_SHIFT) +
204 				      ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
205 				      0, 0);
206 	if (IS_ERR_VALUE(vdso_base)) {
207 		rc = vdso_base;
208 		goto fail_mmapsem;
209 	}
210 
211 	/* Add required alignment. */
212 	vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
213 
214 	/*
215 	 * Put vDSO base into mm struct. We need to do this before calling
216 	 * install_special_mapping or the perf counter mmap tracking code
217 	 * will fail to recognise it as a vDSO (since arch_vma_name fails).
218 	 */
219 	current->mm->context.vdso_base = vdso_base;
220 
221 	/*
222 	 * our vma flags don't have VM_WRITE so by default, the process isn't
223 	 * allowed to write those pages.
224 	 * gdb can break that with ptrace interface, and thus trigger COW on
225 	 * those pages but it's then your responsibility to never do that on
226 	 * the "data" page of the vDSO or you'll stop getting kernel updates
227 	 * and your nice userland gettimeofday will be totally dead.
228 	 * It's fine to use that for setting breakpoints in the vDSO code
229 	 * pages though.
230 	 */
231 	rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
232 				     VM_READ|VM_EXEC|
233 				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
234 				     vdso_pagelist);
235 	if (rc) {
236 		current->mm->context.vdso_base = 0;
237 		goto fail_mmapsem;
238 	}
239 
240 	up_write(&mm->mmap_sem);
241 	return 0;
242 
243  fail_mmapsem:
244 	up_write(&mm->mmap_sem);
245 	return rc;
246 }
247 
248 const char *arch_vma_name(struct vm_area_struct *vma)
249 {
250 	if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
251 		return "[vdso]";
252 	return NULL;
253 }
254 
255 
256 
257 #ifdef CONFIG_VDSO32
258 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
259 				  unsigned long *size)
260 {
261 	Elf32_Shdr *sechdrs;
262 	unsigned int i;
263 	char *secnames;
264 
265 	/* Grab section headers and strings so we can tell who is who */
266 	sechdrs = (void *)ehdr + ehdr->e_shoff;
267 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
268 
269 	/* Find the section they want */
270 	for (i = 1; i < ehdr->e_shnum; i++) {
271 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
272 			if (size)
273 				*size = sechdrs[i].sh_size;
274 			return (void *)ehdr + sechdrs[i].sh_offset;
275 		}
276 	}
277 	*size = 0;
278 	return NULL;
279 }
280 
281 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
282 					const char *symname)
283 {
284 	unsigned int i;
285 	char name[MAX_SYMNAME], *c;
286 
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 
301 /* Note that we assume the section is .text and the symbol is relative to
302  * the library base
303  */
304 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
305 					    const char *symname)
306 {
307 	Elf32_Sym *sym = find_symbol32(lib, symname);
308 
309 	if (sym == NULL) {
310 		printk(KERN_WARNING "vDSO32: function %s not found !\n",
311 		       symname);
312 		return 0;
313 	}
314 	return sym->st_value - VDSO32_LBASE;
315 }
316 
317 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
318 				       struct lib64_elfinfo *v64,
319 				       const char *orig, const char *fix)
320 {
321 	Elf32_Sym *sym32_gen, *sym32_fix;
322 
323 	sym32_gen = find_symbol32(v32, orig);
324 	if (sym32_gen == NULL) {
325 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
326 		return -1;
327 	}
328 	if (fix == NULL) {
329 		sym32_gen->st_name = 0;
330 		return 0;
331 	}
332 	sym32_fix = find_symbol32(v32, fix);
333 	if (sym32_fix == NULL) {
334 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
335 		return -1;
336 	}
337 	sym32_gen->st_value = sym32_fix->st_value;
338 	sym32_gen->st_size = sym32_fix->st_size;
339 	sym32_gen->st_info = sym32_fix->st_info;
340 	sym32_gen->st_other = sym32_fix->st_other;
341 	sym32_gen->st_shndx = sym32_fix->st_shndx;
342 
343 	return 0;
344 }
345 #else /* !CONFIG_VDSO32 */
346 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
347 					    const char *symname)
348 {
349 	return 0;
350 }
351 
352 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
353 				       struct lib64_elfinfo *v64,
354 				       const char *orig, const char *fix)
355 {
356 	return 0;
357 }
358 #endif /* CONFIG_VDSO32 */
359 
360 
361 #ifdef CONFIG_PPC64
362 
363 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
364 				  unsigned long *size)
365 {
366 	Elf64_Shdr *sechdrs;
367 	unsigned int i;
368 	char *secnames;
369 
370 	/* Grab section headers and strings so we can tell who is who */
371 	sechdrs = (void *)ehdr + ehdr->e_shoff;
372 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
373 
374 	/* Find the section they want */
375 	for (i = 1; i < ehdr->e_shnum; i++) {
376 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
377 			if (size)
378 				*size = sechdrs[i].sh_size;
379 			return (void *)ehdr + sechdrs[i].sh_offset;
380 		}
381 	}
382 	if (size)
383 		*size = 0;
384 	return NULL;
385 }
386 
387 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
388 					const char *symname)
389 {
390 	unsigned int i;
391 	char name[MAX_SYMNAME], *c;
392 
393 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
394 		if (lib->dynsym[i].st_name == 0)
395 			continue;
396 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
397 			MAX_SYMNAME);
398 		c = strchr(name, '@');
399 		if (c)
400 			*c = 0;
401 		if (strcmp(symname, name) == 0)
402 			return &lib->dynsym[i];
403 	}
404 	return NULL;
405 }
406 
407 /* Note that we assume the section is .text and the symbol is relative to
408  * the library base
409  */
410 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
411 					    const char *symname)
412 {
413 	Elf64_Sym *sym = find_symbol64(lib, symname);
414 
415 	if (sym == NULL) {
416 		printk(KERN_WARNING "vDSO64: function %s not found !\n",
417 		       symname);
418 		return 0;
419 	}
420 #ifdef VDS64_HAS_DESCRIPTORS
421 	return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
422 		VDSO64_LBASE;
423 #else
424 	return sym->st_value - VDSO64_LBASE;
425 #endif
426 }
427 
428 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
429 				       struct lib64_elfinfo *v64,
430 				       const char *orig, const char *fix)
431 {
432 	Elf64_Sym *sym64_gen, *sym64_fix;
433 
434 	sym64_gen = find_symbol64(v64, orig);
435 	if (sym64_gen == NULL) {
436 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
437 		return -1;
438 	}
439 	if (fix == NULL) {
440 		sym64_gen->st_name = 0;
441 		return 0;
442 	}
443 	sym64_fix = find_symbol64(v64, fix);
444 	if (sym64_fix == NULL) {
445 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
446 		return -1;
447 	}
448 	sym64_gen->st_value = sym64_fix->st_value;
449 	sym64_gen->st_size = sym64_fix->st_size;
450 	sym64_gen->st_info = sym64_fix->st_info;
451 	sym64_gen->st_other = sym64_fix->st_other;
452 	sym64_gen->st_shndx = sym64_fix->st_shndx;
453 
454 	return 0;
455 }
456 
457 #endif /* CONFIG_PPC64 */
458 
459 
460 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
461 					struct lib64_elfinfo *v64)
462 {
463 	void *sect;
464 
465 	/*
466 	 * Locate symbol tables & text section
467 	 */
468 
469 #ifdef CONFIG_VDSO32
470 	v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
471 	v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
472 	if (v32->dynsym == NULL || v32->dynstr == NULL) {
473 		printk(KERN_ERR "vDSO32: required symbol section not found\n");
474 		return -1;
475 	}
476 	sect = find_section32(v32->hdr, ".text", NULL);
477 	if (sect == NULL) {
478 		printk(KERN_ERR "vDSO32: the .text section was not found\n");
479 		return -1;
480 	}
481 	v32->text = sect - vdso32_kbase;
482 #endif
483 
484 #ifdef CONFIG_PPC64
485 	v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
486 	v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
487 	if (v64->dynsym == NULL || v64->dynstr == NULL) {
488 		printk(KERN_ERR "vDSO64: required symbol section not found\n");
489 		return -1;
490 	}
491 	sect = find_section64(v64->hdr, ".text", NULL);
492 	if (sect == NULL) {
493 		printk(KERN_ERR "vDSO64: the .text section was not found\n");
494 		return -1;
495 	}
496 	v64->text = sect - vdso64_kbase;
497 #endif /* CONFIG_PPC64 */
498 
499 	return 0;
500 }
501 
502 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
503 					  struct lib64_elfinfo *v64)
504 {
505 	/*
506 	 * Find signal trampolines
507 	 */
508 
509 #ifdef CONFIG_PPC64
510 	vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
511 #endif
512 	vdso32_sigtramp	   = find_function32(v32, "__kernel_sigtramp32");
513 	vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
514 }
515 
516 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
517 				       struct lib64_elfinfo *v64)
518 {
519 #ifdef CONFIG_VDSO32
520 	Elf32_Sym *sym32;
521 #endif
522 #ifdef CONFIG_PPC64
523 	Elf64_Sym *sym64;
524 
525        	sym64 = find_symbol64(v64, "__kernel_datapage_offset");
526 	if (sym64 == NULL) {
527 		printk(KERN_ERR "vDSO64: Can't find symbol "
528 		       "__kernel_datapage_offset !\n");
529 		return -1;
530 	}
531 	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
532 		(vdso64_pages << PAGE_SHIFT) -
533 		(sym64->st_value - VDSO64_LBASE);
534 #endif /* CONFIG_PPC64 */
535 
536 #ifdef CONFIG_VDSO32
537 	sym32 = find_symbol32(v32, "__kernel_datapage_offset");
538 	if (sym32 == NULL) {
539 		printk(KERN_ERR "vDSO32: Can't find symbol "
540 		       "__kernel_datapage_offset !\n");
541 		return -1;
542 	}
543 	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
544 		(vdso32_pages << PAGE_SHIFT) -
545 		(sym32->st_value - VDSO32_LBASE);
546 #endif
547 
548 	return 0;
549 }
550 
551 
552 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
553 				      struct lib64_elfinfo *v64)
554 {
555 	unsigned long size;
556 	void *start;
557 
558 #ifdef CONFIG_PPC64
559 	start = find_section64(v64->hdr, "__ftr_fixup", &size);
560 	if (start)
561 		do_feature_fixups(cur_cpu_spec->cpu_features,
562 				  start, start + size);
563 
564 	start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);
565 	if (start)
566 		do_feature_fixups(cur_cpu_spec->mmu_features,
567 				  start, start + size);
568 
569 	start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);
570 	if (start)
571 		do_feature_fixups(powerpc_firmware_features,
572 				  start, start + size);
573 
574 	start = find_section64(v64->hdr, "__lwsync_fixup", &size);
575 	if (start)
576 		do_lwsync_fixups(cur_cpu_spec->cpu_features,
577 				 start, start + size);
578 #endif /* CONFIG_PPC64 */
579 
580 #ifdef CONFIG_VDSO32
581 	start = find_section32(v32->hdr, "__ftr_fixup", &size);
582 	if (start)
583 		do_feature_fixups(cur_cpu_spec->cpu_features,
584 				  start, start + size);
585 
586 	start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);
587 	if (start)
588 		do_feature_fixups(cur_cpu_spec->mmu_features,
589 				  start, start + size);
590 
591 #ifdef CONFIG_PPC64
592 	start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);
593 	if (start)
594 		do_feature_fixups(powerpc_firmware_features,
595 				  start, start + size);
596 #endif /* CONFIG_PPC64 */
597 
598 	start = find_section32(v32->hdr, "__lwsync_fixup", &size);
599 	if (start)
600 		do_lwsync_fixups(cur_cpu_spec->cpu_features,
601 				 start, start + size);
602 #endif
603 
604 	return 0;
605 }
606 
607 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
608 				       struct lib64_elfinfo *v64)
609 {
610 	int i;
611 
612 	for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
613 		struct vdso_patch_def *patch = &vdso_patches[i];
614 		int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
615 			== patch->ftr_value;
616 		if (!match)
617 			continue;
618 
619 		DBG("replacing %s with %s...\n", patch->gen_name,
620 		    patch->fix_name ? "NONE" : patch->fix_name);
621 
622 		/*
623 		 * Patch the 32 bits and 64 bits symbols. Note that we do not
624 		 * patch the "." symbol on 64 bits.
625 		 * It would be easy to do, but doesn't seem to be necessary,
626 		 * patching the OPD symbol is enough.
627 		 */
628 		vdso_do_func_patch32(v32, v64, patch->gen_name,
629 				     patch->fix_name);
630 #ifdef CONFIG_PPC64
631 		vdso_do_func_patch64(v32, v64, patch->gen_name,
632 				     patch->fix_name);
633 #endif /* CONFIG_PPC64 */
634 	}
635 
636 	return 0;
637 }
638 
639 
640 static __init int vdso_setup(void)
641 {
642 	struct lib32_elfinfo	v32;
643 	struct lib64_elfinfo	v64;
644 
645 	v32.hdr = vdso32_kbase;
646 #ifdef CONFIG_PPC64
647 	v64.hdr = vdso64_kbase;
648 #endif
649 	if (vdso_do_find_sections(&v32, &v64))
650 		return -1;
651 
652 	if (vdso_fixup_datapage(&v32, &v64))
653 		return -1;
654 
655 	if (vdso_fixup_features(&v32, &v64))
656 		return -1;
657 
658 	if (vdso_fixup_alt_funcs(&v32, &v64))
659 		return -1;
660 
661 	vdso_setup_trampolines(&v32, &v64);
662 
663 	return 0;
664 }
665 
666 /*
667  * Called from setup_arch to initialize the bitmap of available
668  * syscalls in the systemcfg page
669  */
670 static void __init vdso_setup_syscall_map(void)
671 {
672 	unsigned int i;
673 	extern unsigned long *sys_call_table;
674 #ifdef CONFIG_PPC64
675 	extern unsigned long *compat_sys_call_table;
676 #endif
677 	extern unsigned long sys_ni_syscall;
678 
679 
680 	for (i = 0; i < NR_syscalls; i++) {
681 #ifdef CONFIG_PPC64
682 		if (sys_call_table[i] != sys_ni_syscall)
683 			vdso_data->syscall_map_64[i >> 5] |=
684 				0x80000000UL >> (i & 0x1f);
685 		if (compat_sys_call_table[i] != sys_ni_syscall)
686 			vdso_data->syscall_map_32[i >> 5] |=
687 				0x80000000UL >> (i & 0x1f);
688 #else /* CONFIG_PPC64 */
689 		if (sys_call_table[i] != sys_ni_syscall)
690 			vdso_data->syscall_map_32[i >> 5] |=
691 				0x80000000UL >> (i & 0x1f);
692 #endif /* CONFIG_PPC64 */
693 	}
694 }
695 
696 #ifdef CONFIG_PPC64
697 int vdso_getcpu_init(void)
698 {
699 	unsigned long cpu, node, val;
700 
701 	/*
702 	 * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
703 	 * in the next 16 bits.  The VDSO uses this to implement getcpu().
704 	 */
705 	cpu = get_cpu();
706 	WARN_ON_ONCE(cpu > 0xffff);
707 
708 	node = cpu_to_node(cpu);
709 	WARN_ON_ONCE(node > 0xffff);
710 
711 	val = (cpu & 0xfff) | ((node & 0xffff) << 16);
712 	mtspr(SPRN_SPRG_VDSO_WRITE, val);
713 	get_paca()->sprg_vdso = val;
714 
715 	put_cpu();
716 
717 	return 0;
718 }
719 /* We need to call this before SMP init */
720 early_initcall(vdso_getcpu_init);
721 #endif
722 
723 static int __init vdso_init(void)
724 {
725 	int i;
726 
727 #ifdef CONFIG_PPC64
728 	/*
729 	 * Fill up the "systemcfg" stuff for backward compatibility
730 	 */
731 	strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
732 	vdso_data->version.major = SYSTEMCFG_MAJOR;
733 	vdso_data->version.minor = SYSTEMCFG_MINOR;
734 	vdso_data->processor = mfspr(SPRN_PVR);
735 	/*
736 	 * Fake the old platform number for pSeries and add
737 	 * in LPAR bit if necessary
738 	 */
739 	vdso_data->platform = 0x100;
740 	if (firmware_has_feature(FW_FEATURE_LPAR))
741 		vdso_data->platform |= 1;
742 	vdso_data->physicalMemorySize = memblock_phys_mem_size();
743 	vdso_data->dcache_size = ppc64_caches.l1d.size;
744 	vdso_data->dcache_line_size = ppc64_caches.l1d.line_size;
745 	vdso_data->icache_size = ppc64_caches.l1i.size;
746 	vdso_data->icache_line_size = ppc64_caches.l1i.line_size;
747 	vdso_data->dcache_block_size = ppc64_caches.l1d.block_size;
748 	vdso_data->icache_block_size = ppc64_caches.l1i.block_size;
749 	vdso_data->dcache_log_block_size = ppc64_caches.l1d.log_block_size;
750 	vdso_data->icache_log_block_size = ppc64_caches.l1i.log_block_size;
751 
752 	/*
753 	 * Calculate the size of the 64 bits vDSO
754 	 */
755 	vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
756 	DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
757 #else
758 	vdso_data->dcache_block_size = L1_CACHE_BYTES;
759 	vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
760 	vdso_data->icache_block_size = L1_CACHE_BYTES;
761 	vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
762 #endif /* CONFIG_PPC64 */
763 
764 
765 #ifdef CONFIG_VDSO32
766 	vdso32_kbase = &vdso32_start;
767 
768 	/*
769 	 * Calculate the size of the 32 bits vDSO
770 	 */
771 	vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
772 	DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
773 #endif
774 
775 
776 	/*
777 	 * Setup the syscall map in the vDOS
778 	 */
779 	vdso_setup_syscall_map();
780 
781 	/*
782 	 * Initialize the vDSO images in memory, that is do necessary
783 	 * fixups of vDSO symbols, locate trampolines, etc...
784 	 */
785 	if (vdso_setup()) {
786 		printk(KERN_ERR "vDSO setup failure, not enabled !\n");
787 		vdso32_pages = 0;
788 #ifdef CONFIG_PPC64
789 		vdso64_pages = 0;
790 #endif
791 		return 0;
792 	}
793 
794 #ifdef CONFIG_VDSO32
795 	/* Make sure pages are in the correct state */
796 	vdso32_pagelist = kcalloc(vdso32_pages + 2, sizeof(struct page *),
797 				  GFP_KERNEL);
798 	BUG_ON(vdso32_pagelist == NULL);
799 	for (i = 0; i < vdso32_pages; i++) {
800 		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
801 		get_page(pg);
802 		vdso32_pagelist[i] = pg;
803 	}
804 	vdso32_pagelist[i++] = virt_to_page(vdso_data);
805 	vdso32_pagelist[i] = NULL;
806 #endif
807 
808 #ifdef CONFIG_PPC64
809 	vdso64_pagelist = kcalloc(vdso64_pages + 2, sizeof(struct page *),
810 				  GFP_KERNEL);
811 	BUG_ON(vdso64_pagelist == NULL);
812 	for (i = 0; i < vdso64_pages; i++) {
813 		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
814 		get_page(pg);
815 		vdso64_pagelist[i] = pg;
816 	}
817 	vdso64_pagelist[i++] = virt_to_page(vdso_data);
818 	vdso64_pagelist[i] = NULL;
819 #endif /* CONFIG_PPC64 */
820 
821 	get_page(virt_to_page(vdso_data));
822 
823 	smp_wmb();
824 	vdso_ready = 1;
825 
826 	return 0;
827 }
828 arch_initcall(vdso_init);
829