xref: /openbmc/linux/arch/powerpc/kernel/vdso.c (revision 68198dca)
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/cpu_has_feature.h>
26 #include <asm/pgtable.h>
27 #include <asm/processor.h>
28 #include <asm/mmu.h>
29 #include <asm/mmu_context.h>
30 #include <asm/prom.h>
31 #include <asm/machdep.h>
32 #include <asm/cputable.h>
33 #include <asm/sections.h>
34 #include <asm/firmware.h>
35 #include <asm/vdso.h>
36 #include <asm/vdso_datapage.h>
37 #include <asm/setup.h>
38 
39 #undef DEBUG
40 
41 #ifdef DEBUG
42 #define DBG(fmt...) printk(fmt)
43 #else
44 #define DBG(fmt...)
45 #endif
46 
47 /* Max supported size for symbol names */
48 #define MAX_SYMNAME	64
49 
50 /* The alignment of the vDSO */
51 #define VDSO_ALIGNMENT	(1 << 16)
52 
53 static unsigned int vdso32_pages;
54 static void *vdso32_kbase;
55 static struct page **vdso32_pagelist;
56 unsigned long vdso32_sigtramp;
57 unsigned long vdso32_rt_sigtramp;
58 
59 #ifdef CONFIG_VDSO32
60 extern char vdso32_start, vdso32_end;
61 #endif
62 
63 #ifdef CONFIG_PPC64
64 extern char vdso64_start, vdso64_end;
65 static void *vdso64_kbase = &vdso64_start;
66 static unsigned int vdso64_pages;
67 static struct page **vdso64_pagelist;
68 unsigned long vdso64_rt_sigtramp;
69 #endif /* CONFIG_PPC64 */
70 
71 static int vdso_ready;
72 
73 /*
74  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
75  * Once the early boot kernel code no longer needs to muck around
76  * with it, it will become dynamically allocated
77  */
78 static union {
79 	struct vdso_data	data;
80 	u8			page[PAGE_SIZE];
81 } vdso_data_store __page_aligned_data;
82 struct vdso_data *vdso_data = &vdso_data_store.data;
83 
84 /* Format of the patch table */
85 struct vdso_patch_def
86 {
87 	unsigned long	ftr_mask, ftr_value;
88 	const char	*gen_name;
89 	const char	*fix_name;
90 };
91 
92 /* Table of functions to patch based on the CPU type/revision
93  *
94  * Currently, we only change sync_dicache to do nothing on processors
95  * with a coherent icache
96  */
97 static struct vdso_patch_def vdso_patches[] = {
98 	{
99 		CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
100 		"__kernel_sync_dicache", "__kernel_sync_dicache_p5"
101 	},
102 	{
103 		CPU_FTR_USE_TB, 0,
104 		"__kernel_gettimeofday", NULL
105 	},
106 	{
107 		CPU_FTR_USE_TB, 0,
108 		"__kernel_clock_gettime", NULL
109 	},
110 	{
111 		CPU_FTR_USE_TB, 0,
112 		"__kernel_clock_getres", NULL
113 	},
114 	{
115 		CPU_FTR_USE_TB, 0,
116 		"__kernel_get_tbfreq", NULL
117 	},
118 	{
119 		CPU_FTR_USE_TB, 0,
120 		"__kernel_time", NULL
121 	},
122 };
123 
124 /*
125  * Some infos carried around for each of them during parsing at
126  * boot time.
127  */
128 struct lib32_elfinfo
129 {
130 	Elf32_Ehdr	*hdr;		/* ptr to ELF */
131 	Elf32_Sym	*dynsym;	/* ptr to .dynsym section */
132 	unsigned long	dynsymsize;	/* size of .dynsym section */
133 	char		*dynstr;	/* ptr to .dynstr section */
134 	unsigned long	text;		/* offset of .text section in .so */
135 };
136 
137 struct lib64_elfinfo
138 {
139 	Elf64_Ehdr	*hdr;
140 	Elf64_Sym	*dynsym;
141 	unsigned long	dynsymsize;
142 	char		*dynstr;
143 	unsigned long	text;
144 };
145 
146 
147 /*
148  * This is called from binfmt_elf, we create the special vma for the
149  * vDSO and insert it into the mm struct tree
150  */
151 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
152 {
153 	struct mm_struct *mm = current->mm;
154 	struct page **vdso_pagelist;
155 	unsigned long vdso_pages;
156 	unsigned long vdso_base;
157 	int rc;
158 
159 	if (!vdso_ready)
160 		return 0;
161 
162 #ifdef CONFIG_PPC64
163 	if (is_32bit_task()) {
164 		vdso_pagelist = vdso32_pagelist;
165 		vdso_pages = vdso32_pages;
166 		vdso_base = VDSO32_MBASE;
167 	} else {
168 		vdso_pagelist = vdso64_pagelist;
169 		vdso_pages = vdso64_pages;
170 		/*
171 		 * On 64bit we don't have a preferred map address. This
172 		 * allows get_unmapped_area to find an area near other mmaps
173 		 * and most likely share a SLB entry.
174 		 */
175 		vdso_base = 0;
176 	}
177 #else
178 	vdso_pagelist = vdso32_pagelist;
179 	vdso_pages = vdso32_pages;
180 	vdso_base = VDSO32_MBASE;
181 #endif
182 
183 	current->mm->context.vdso_base = 0;
184 
185 	/* vDSO has a problem and was disabled, just don't "enable" it for the
186 	 * process
187 	 */
188 	if (vdso_pages == 0)
189 		return 0;
190 	/* Add a page to the vdso size for the data page */
191 	vdso_pages ++;
192 
193 	/*
194 	 * pick a base address for the vDSO in process space. We try to put it
195 	 * at vdso_base which is the "natural" base for it, but we might fail
196 	 * and end up putting it elsewhere.
197 	 * Add enough to the size so that the result can be aligned.
198 	 */
199 	if (down_write_killable(&mm->mmap_sem))
200 		return -EINTR;
201 	vdso_base = get_unmapped_area(NULL, vdso_base,
202 				      (vdso_pages << PAGE_SHIFT) +
203 				      ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
204 				      0, 0);
205 	if (IS_ERR_VALUE(vdso_base)) {
206 		rc = vdso_base;
207 		goto fail_mmapsem;
208 	}
209 
210 	/* Add required alignment. */
211 	vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
212 
213 	/*
214 	 * Put vDSO base into mm struct. We need to do this before calling
215 	 * install_special_mapping or the perf counter mmap tracking code
216 	 * will fail to recognise it as a vDSO (since arch_vma_name fails).
217 	 */
218 	current->mm->context.vdso_base = vdso_base;
219 
220 	/*
221 	 * our vma flags don't have VM_WRITE so by default, the process isn't
222 	 * allowed to write those pages.
223 	 * gdb can break that with ptrace interface, and thus trigger COW on
224 	 * those pages but it's then your responsibility to never do that on
225 	 * the "data" page of the vDSO or you'll stop getting kernel updates
226 	 * and your nice userland gettimeofday will be totally dead.
227 	 * It's fine to use that for setting breakpoints in the vDSO code
228 	 * pages though.
229 	 */
230 	rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
231 				     VM_READ|VM_EXEC|
232 				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
233 				     vdso_pagelist);
234 	if (rc) {
235 		current->mm->context.vdso_base = 0;
236 		goto fail_mmapsem;
237 	}
238 
239 	up_write(&mm->mmap_sem);
240 	return 0;
241 
242  fail_mmapsem:
243 	up_write(&mm->mmap_sem);
244 	return rc;
245 }
246 
247 const char *arch_vma_name(struct vm_area_struct *vma)
248 {
249 	if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
250 		return "[vdso]";
251 	return NULL;
252 }
253 
254 
255 
256 #ifdef CONFIG_VDSO32
257 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
258 				  unsigned long *size)
259 {
260 	Elf32_Shdr *sechdrs;
261 	unsigned int i;
262 	char *secnames;
263 
264 	/* Grab section headers and strings so we can tell who is who */
265 	sechdrs = (void *)ehdr + ehdr->e_shoff;
266 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
267 
268 	/* Find the section they want */
269 	for (i = 1; i < ehdr->e_shnum; i++) {
270 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
271 			if (size)
272 				*size = sechdrs[i].sh_size;
273 			return (void *)ehdr + sechdrs[i].sh_offset;
274 		}
275 	}
276 	*size = 0;
277 	return NULL;
278 }
279 
280 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
281 					const char *symname)
282 {
283 	unsigned int i;
284 	char name[MAX_SYMNAME], *c;
285 
286 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
287 		if (lib->dynsym[i].st_name == 0)
288 			continue;
289 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
290 			MAX_SYMNAME);
291 		c = strchr(name, '@');
292 		if (c)
293 			*c = 0;
294 		if (strcmp(symname, name) == 0)
295 			return &lib->dynsym[i];
296 	}
297 	return NULL;
298 }
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 
308 	if (sym == NULL) {
309 		printk(KERN_WARNING "vDSO32: function %s not found !\n",
310 		       symname);
311 		return 0;
312 	}
313 	return sym->st_value - VDSO32_LBASE;
314 }
315 
316 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
317 				       struct lib64_elfinfo *v64,
318 				       const char *orig, const char *fix)
319 {
320 	Elf32_Sym *sym32_gen, *sym32_fix;
321 
322 	sym32_gen = find_symbol32(v32, orig);
323 	if (sym32_gen == NULL) {
324 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
325 		return -1;
326 	}
327 	if (fix == NULL) {
328 		sym32_gen->st_name = 0;
329 		return 0;
330 	}
331 	sym32_fix = find_symbol32(v32, fix);
332 	if (sym32_fix == NULL) {
333 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
334 		return -1;
335 	}
336 	sym32_gen->st_value = sym32_fix->st_value;
337 	sym32_gen->st_size = sym32_fix->st_size;
338 	sym32_gen->st_info = sym32_fix->st_info;
339 	sym32_gen->st_other = sym32_fix->st_other;
340 	sym32_gen->st_shndx = sym32_fix->st_shndx;
341 
342 	return 0;
343 }
344 #else /* !CONFIG_VDSO32 */
345 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
346 					    const char *symname)
347 {
348 	return 0;
349 }
350 
351 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
352 				       struct lib64_elfinfo *v64,
353 				       const char *orig, const char *fix)
354 {
355 	return 0;
356 }
357 #endif /* CONFIG_VDSO32 */
358 
359 
360 #ifdef CONFIG_PPC64
361 
362 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
363 				  unsigned long *size)
364 {
365 	Elf64_Shdr *sechdrs;
366 	unsigned int i;
367 	char *secnames;
368 
369 	/* Grab section headers and strings so we can tell who is who */
370 	sechdrs = (void *)ehdr + ehdr->e_shoff;
371 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
372 
373 	/* Find the section they want */
374 	for (i = 1; i < ehdr->e_shnum; i++) {
375 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
376 			if (size)
377 				*size = sechdrs[i].sh_size;
378 			return (void *)ehdr + sechdrs[i].sh_offset;
379 		}
380 	}
381 	if (size)
382 		*size = 0;
383 	return NULL;
384 }
385 
386 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
387 					const char *symname)
388 {
389 	unsigned int i;
390 	char name[MAX_SYMNAME], *c;
391 
392 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
393 		if (lib->dynsym[i].st_name == 0)
394 			continue;
395 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
396 			MAX_SYMNAME);
397 		c = strchr(name, '@');
398 		if (c)
399 			*c = 0;
400 		if (strcmp(symname, name) == 0)
401 			return &lib->dynsym[i];
402 	}
403 	return NULL;
404 }
405 
406 /* Note that we assume the section is .text and the symbol is relative to
407  * the library base
408  */
409 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
410 					    const char *symname)
411 {
412 	Elf64_Sym *sym = find_symbol64(lib, symname);
413 
414 	if (sym == NULL) {
415 		printk(KERN_WARNING "vDSO64: function %s not found !\n",
416 		       symname);
417 		return 0;
418 	}
419 #ifdef VDS64_HAS_DESCRIPTORS
420 	return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
421 		VDSO64_LBASE;
422 #else
423 	return sym->st_value - VDSO64_LBASE;
424 #endif
425 }
426 
427 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
428 				       struct lib64_elfinfo *v64,
429 				       const char *orig, const char *fix)
430 {
431 	Elf64_Sym *sym64_gen, *sym64_fix;
432 
433 	sym64_gen = find_symbol64(v64, orig);
434 	if (sym64_gen == NULL) {
435 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
436 		return -1;
437 	}
438 	if (fix == NULL) {
439 		sym64_gen->st_name = 0;
440 		return 0;
441 	}
442 	sym64_fix = find_symbol64(v64, fix);
443 	if (sym64_fix == NULL) {
444 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
445 		return -1;
446 	}
447 	sym64_gen->st_value = sym64_fix->st_value;
448 	sym64_gen->st_size = sym64_fix->st_size;
449 	sym64_gen->st_info = sym64_fix->st_info;
450 	sym64_gen->st_other = sym64_fix->st_other;
451 	sym64_gen->st_shndx = sym64_fix->st_shndx;
452 
453 	return 0;
454 }
455 
456 #endif /* CONFIG_PPC64 */
457 
458 
459 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
460 					struct lib64_elfinfo *v64)
461 {
462 	void *sect;
463 
464 	/*
465 	 * Locate symbol tables & text section
466 	 */
467 
468 #ifdef CONFIG_VDSO32
469 	v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
470 	v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
471 	if (v32->dynsym == NULL || v32->dynstr == NULL) {
472 		printk(KERN_ERR "vDSO32: required symbol section not found\n");
473 		return -1;
474 	}
475 	sect = find_section32(v32->hdr, ".text", NULL);
476 	if (sect == NULL) {
477 		printk(KERN_ERR "vDSO32: the .text section was not found\n");
478 		return -1;
479 	}
480 	v32->text = sect - vdso32_kbase;
481 #endif
482 
483 #ifdef CONFIG_PPC64
484 	v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
485 	v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
486 	if (v64->dynsym == NULL || v64->dynstr == NULL) {
487 		printk(KERN_ERR "vDSO64: required symbol section not found\n");
488 		return -1;
489 	}
490 	sect = find_section64(v64->hdr, ".text", NULL);
491 	if (sect == NULL) {
492 		printk(KERN_ERR "vDSO64: the .text section was not found\n");
493 		return -1;
494 	}
495 	v64->text = sect - vdso64_kbase;
496 #endif /* CONFIG_PPC64 */
497 
498 	return 0;
499 }
500 
501 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
502 					  struct lib64_elfinfo *v64)
503 {
504 	/*
505 	 * Find signal trampolines
506 	 */
507 
508 #ifdef CONFIG_PPC64
509 	vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
510 #endif
511 	vdso32_sigtramp	   = find_function32(v32, "__kernel_sigtramp32");
512 	vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
513 }
514 
515 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
516 				       struct lib64_elfinfo *v64)
517 {
518 #ifdef CONFIG_VDSO32
519 	Elf32_Sym *sym32;
520 #endif
521 #ifdef CONFIG_PPC64
522 	Elf64_Sym *sym64;
523 
524        	sym64 = find_symbol64(v64, "__kernel_datapage_offset");
525 	if (sym64 == NULL) {
526 		printk(KERN_ERR "vDSO64: Can't find symbol "
527 		       "__kernel_datapage_offset !\n");
528 		return -1;
529 	}
530 	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
531 		(vdso64_pages << PAGE_SHIFT) -
532 		(sym64->st_value - VDSO64_LBASE);
533 #endif /* CONFIG_PPC64 */
534 
535 #ifdef CONFIG_VDSO32
536 	sym32 = find_symbol32(v32, "__kernel_datapage_offset");
537 	if (sym32 == NULL) {
538 		printk(KERN_ERR "vDSO32: Can't find symbol "
539 		       "__kernel_datapage_offset !\n");
540 		return -1;
541 	}
542 	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
543 		(vdso32_pages << PAGE_SHIFT) -
544 		(sym32->st_value - VDSO32_LBASE);
545 #endif
546 
547 	return 0;
548 }
549 
550 
551 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
552 				      struct lib64_elfinfo *v64)
553 {
554 	unsigned long size;
555 	void *start;
556 
557 #ifdef CONFIG_PPC64
558 	start = find_section64(v64->hdr, "__ftr_fixup", &size);
559 	if (start)
560 		do_feature_fixups(cur_cpu_spec->cpu_features,
561 				  start, start + size);
562 
563 	start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);
564 	if (start)
565 		do_feature_fixups(cur_cpu_spec->mmu_features,
566 				  start, start + size);
567 
568 	start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);
569 	if (start)
570 		do_feature_fixups(powerpc_firmware_features,
571 				  start, start + size);
572 
573 	start = find_section64(v64->hdr, "__lwsync_fixup", &size);
574 	if (start)
575 		do_lwsync_fixups(cur_cpu_spec->cpu_features,
576 				 start, start + size);
577 #endif /* CONFIG_PPC64 */
578 
579 #ifdef CONFIG_VDSO32
580 	start = find_section32(v32->hdr, "__ftr_fixup", &size);
581 	if (start)
582 		do_feature_fixups(cur_cpu_spec->cpu_features,
583 				  start, start + size);
584 
585 	start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);
586 	if (start)
587 		do_feature_fixups(cur_cpu_spec->mmu_features,
588 				  start, start + size);
589 
590 #ifdef CONFIG_PPC64
591 	start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);
592 	if (start)
593 		do_feature_fixups(powerpc_firmware_features,
594 				  start, start + size);
595 #endif /* CONFIG_PPC64 */
596 
597 	start = find_section32(v32->hdr, "__lwsync_fixup", &size);
598 	if (start)
599 		do_lwsync_fixups(cur_cpu_spec->cpu_features,
600 				 start, start + size);
601 #endif
602 
603 	return 0;
604 }
605 
606 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
607 				       struct lib64_elfinfo *v64)
608 {
609 	int i;
610 
611 	for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
612 		struct vdso_patch_def *patch = &vdso_patches[i];
613 		int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
614 			== patch->ftr_value;
615 		if (!match)
616 			continue;
617 
618 		DBG("replacing %s with %s...\n", patch->gen_name,
619 		    patch->fix_name ? "NONE" : patch->fix_name);
620 
621 		/*
622 		 * Patch the 32 bits and 64 bits symbols. Note that we do not
623 		 * patch the "." symbol on 64 bits.
624 		 * It would be easy to do, but doesn't seem to be necessary,
625 		 * patching the OPD symbol is enough.
626 		 */
627 		vdso_do_func_patch32(v32, v64, patch->gen_name,
628 				     patch->fix_name);
629 #ifdef CONFIG_PPC64
630 		vdso_do_func_patch64(v32, v64, patch->gen_name,
631 				     patch->fix_name);
632 #endif /* CONFIG_PPC64 */
633 	}
634 
635 	return 0;
636 }
637 
638 
639 static __init int vdso_setup(void)
640 {
641 	struct lib32_elfinfo	v32;
642 	struct lib64_elfinfo	v64;
643 
644 	v32.hdr = vdso32_kbase;
645 #ifdef CONFIG_PPC64
646 	v64.hdr = vdso64_kbase;
647 #endif
648 	if (vdso_do_find_sections(&v32, &v64))
649 		return -1;
650 
651 	if (vdso_fixup_datapage(&v32, &v64))
652 		return -1;
653 
654 	if (vdso_fixup_features(&v32, &v64))
655 		return -1;
656 
657 	if (vdso_fixup_alt_funcs(&v32, &v64))
658 		return -1;
659 
660 	vdso_setup_trampolines(&v32, &v64);
661 
662 	return 0;
663 }
664 
665 /*
666  * Called from setup_arch to initialize the bitmap of available
667  * syscalls in the systemcfg page
668  */
669 static void __init vdso_setup_syscall_map(void)
670 {
671 	unsigned int i;
672 	extern unsigned long *sys_call_table;
673 	extern unsigned long sys_ni_syscall;
674 
675 
676 	for (i = 0; i < NR_syscalls; i++) {
677 #ifdef CONFIG_PPC64
678 		if (sys_call_table[i*2] != sys_ni_syscall)
679 			vdso_data->syscall_map_64[i >> 5] |=
680 				0x80000000UL >> (i & 0x1f);
681 		if (sys_call_table[i*2+1] != sys_ni_syscall)
682 			vdso_data->syscall_map_32[i >> 5] |=
683 				0x80000000UL >> (i & 0x1f);
684 #else /* CONFIG_PPC64 */
685 		if (sys_call_table[i] != sys_ni_syscall)
686 			vdso_data->syscall_map_32[i >> 5] |=
687 				0x80000000UL >> (i & 0x1f);
688 #endif /* CONFIG_PPC64 */
689 	}
690 }
691 
692 #ifdef CONFIG_PPC64
693 int vdso_getcpu_init(void)
694 {
695 	unsigned long cpu, node, val;
696 
697 	/*
698 	 * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
699 	 * in the next 16 bits.  The VDSO uses this to implement getcpu().
700 	 */
701 	cpu = get_cpu();
702 	WARN_ON_ONCE(cpu > 0xffff);
703 
704 	node = cpu_to_node(cpu);
705 	WARN_ON_ONCE(node > 0xffff);
706 
707 	val = (cpu & 0xfff) | ((node & 0xffff) << 16);
708 	mtspr(SPRN_SPRG_VDSO_WRITE, val);
709 	get_paca()->sprg_vdso = val;
710 
711 	put_cpu();
712 
713 	return 0;
714 }
715 /* We need to call this before SMP init */
716 early_initcall(vdso_getcpu_init);
717 #endif
718 
719 static int __init vdso_init(void)
720 {
721 	int i;
722 
723 #ifdef CONFIG_PPC64
724 	/*
725 	 * Fill up the "systemcfg" stuff for backward compatibility
726 	 */
727 	strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
728 	vdso_data->version.major = SYSTEMCFG_MAJOR;
729 	vdso_data->version.minor = SYSTEMCFG_MINOR;
730 	vdso_data->processor = mfspr(SPRN_PVR);
731 	/*
732 	 * Fake the old platform number for pSeries and add
733 	 * in LPAR bit if necessary
734 	 */
735 	vdso_data->platform = 0x100;
736 	if (firmware_has_feature(FW_FEATURE_LPAR))
737 		vdso_data->platform |= 1;
738 	vdso_data->physicalMemorySize = memblock_phys_mem_size();
739 	vdso_data->dcache_size = ppc64_caches.l1d.size;
740 	vdso_data->dcache_line_size = ppc64_caches.l1d.line_size;
741 	vdso_data->icache_size = ppc64_caches.l1i.size;
742 	vdso_data->icache_line_size = ppc64_caches.l1i.line_size;
743 	vdso_data->dcache_block_size = ppc64_caches.l1d.block_size;
744 	vdso_data->icache_block_size = ppc64_caches.l1i.block_size;
745 	vdso_data->dcache_log_block_size = ppc64_caches.l1d.log_block_size;
746 	vdso_data->icache_log_block_size = ppc64_caches.l1i.log_block_size;
747 
748 	/*
749 	 * Calculate the size of the 64 bits vDSO
750 	 */
751 	vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
752 	DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
753 #else
754 	vdso_data->dcache_block_size = L1_CACHE_BYTES;
755 	vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
756 	vdso_data->icache_block_size = L1_CACHE_BYTES;
757 	vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
758 #endif /* CONFIG_PPC64 */
759 
760 
761 #ifdef CONFIG_VDSO32
762 	vdso32_kbase = &vdso32_start;
763 
764 	/*
765 	 * Calculate the size of the 32 bits vDSO
766 	 */
767 	vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
768 	DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
769 #endif
770 
771 
772 	/*
773 	 * Setup the syscall map in the vDOS
774 	 */
775 	vdso_setup_syscall_map();
776 
777 	/*
778 	 * Initialize the vDSO images in memory, that is do necessary
779 	 * fixups of vDSO symbols, locate trampolines, etc...
780 	 */
781 	if (vdso_setup()) {
782 		printk(KERN_ERR "vDSO setup failure, not enabled !\n");
783 		vdso32_pages = 0;
784 #ifdef CONFIG_PPC64
785 		vdso64_pages = 0;
786 #endif
787 		return 0;
788 	}
789 
790 #ifdef CONFIG_VDSO32
791 	/* Make sure pages are in the correct state */
792 	vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
793 				  GFP_KERNEL);
794 	BUG_ON(vdso32_pagelist == NULL);
795 	for (i = 0; i < vdso32_pages; i++) {
796 		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
797 		ClearPageReserved(pg);
798 		get_page(pg);
799 		vdso32_pagelist[i] = pg;
800 	}
801 	vdso32_pagelist[i++] = virt_to_page(vdso_data);
802 	vdso32_pagelist[i] = NULL;
803 #endif
804 
805 #ifdef CONFIG_PPC64
806 	vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
807 				  GFP_KERNEL);
808 	BUG_ON(vdso64_pagelist == NULL);
809 	for (i = 0; i < vdso64_pages; i++) {
810 		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
811 		ClearPageReserved(pg);
812 		get_page(pg);
813 		vdso64_pagelist[i] = pg;
814 	}
815 	vdso64_pagelist[i++] = virt_to_page(vdso_data);
816 	vdso64_pagelist[i] = NULL;
817 #endif /* CONFIG_PPC64 */
818 
819 	get_page(virt_to_page(vdso_data));
820 
821 	smp_wmb();
822 	vdso_ready = 1;
823 
824 	return 0;
825 }
826 arch_initcall(vdso_init);
827