xref: /linux/arch/powerpc/kernel/vdso.c (revision 2b8232ce512105e28453f301d1510de8363bccd1)
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 
11 #include <linux/module.h>
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/bootmem.h>
24 
25 #include <asm/pgtable.h>
26 #include <asm/system.h>
27 #include <asm/processor.h>
28 #include <asm/mmu.h>
29 #include <asm/mmu_context.h>
30 #include <asm/lmb.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 
38 #include "setup.h"
39 
40 #undef DEBUG
41 
42 #ifdef DEBUG
43 #define DBG(fmt...) printk(fmt)
44 #else
45 #define DBG(fmt...)
46 #endif
47 
48 /* Max supported size for symbol names */
49 #define MAX_SYMNAME	64
50 
51 extern char vdso32_start, vdso32_end;
52 static void *vdso32_kbase = &vdso32_start;
53 static unsigned int vdso32_pages;
54 static struct page **vdso32_pagelist;
55 unsigned long vdso32_sigtramp;
56 unsigned long vdso32_rt_sigtramp;
57 
58 #ifdef CONFIG_PPC64
59 extern char vdso64_start, vdso64_end;
60 static void *vdso64_kbase = &vdso64_start;
61 static unsigned int vdso64_pages;
62 static struct page **vdso64_pagelist;
63 unsigned long vdso64_rt_sigtramp;
64 #endif /* CONFIG_PPC64 */
65 
66 static int vdso_ready;
67 
68 /*
69  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
70  * Once the early boot kernel code no longer needs to muck around
71  * with it, it will become dynamically allocated
72  */
73 static union {
74 	struct vdso_data	data;
75 	u8			page[PAGE_SIZE];
76 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
77 struct vdso_data *vdso_data = &vdso_data_store.data;
78 
79 /* Format of the patch table */
80 struct vdso_patch_def
81 {
82 	unsigned long	ftr_mask, ftr_value;
83 	const char	*gen_name;
84 	const char	*fix_name;
85 };
86 
87 /* Table of functions to patch based on the CPU type/revision
88  *
89  * Currently, we only change sync_dicache to do nothing on processors
90  * with a coherent icache
91  */
92 static struct vdso_patch_def vdso_patches[] = {
93 	{
94 		CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
95 		"__kernel_sync_dicache", "__kernel_sync_dicache_p5"
96 	},
97 	{
98 		CPU_FTR_USE_TB, 0,
99 		"__kernel_gettimeofday", NULL
100 	},
101 	{
102 		CPU_FTR_USE_TB, 0,
103 		"__kernel_clock_gettime", NULL
104 	},
105 	{
106 		CPU_FTR_USE_TB, 0,
107 		"__kernel_clock_getres", NULL
108 	},
109 	{
110 		CPU_FTR_USE_TB, 0,
111 		"__kernel_get_tbfreq", NULL
112 	},
113 };
114 
115 /*
116  * Some infos carried around for each of them during parsing at
117  * boot time.
118  */
119 struct lib32_elfinfo
120 {
121 	Elf32_Ehdr	*hdr;		/* ptr to ELF */
122 	Elf32_Sym	*dynsym;	/* ptr to .dynsym section */
123 	unsigned long	dynsymsize;	/* size of .dynsym section */
124 	char		*dynstr;	/* ptr to .dynstr section */
125 	unsigned long	text;		/* offset of .text section in .so */
126 };
127 
128 struct lib64_elfinfo
129 {
130 	Elf64_Ehdr	*hdr;
131 	Elf64_Sym	*dynsym;
132 	unsigned long	dynsymsize;
133 	char		*dynstr;
134 	unsigned long	text;
135 };
136 
137 
138 #ifdef __DEBUG
139 static void dump_one_vdso_page(struct page *pg, struct page *upg)
140 {
141 	printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
142 	       page_count(pg),
143 	       pg->flags);
144 	if (upg/* && pg != upg*/) {
145 		printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
146 						       << PAGE_SHIFT),
147 		       page_count(upg),
148 		       upg->flags);
149 	}
150 	printk("\n");
151 }
152 
153 static void dump_vdso_pages(struct vm_area_struct * vma)
154 {
155 	int i;
156 
157 	if (!vma || test_thread_flag(TIF_32BIT)) {
158 		printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
159 		for (i=0; i<vdso32_pages; i++) {
160 			struct page *pg = virt_to_page(vdso32_kbase +
161 						       i*PAGE_SIZE);
162 			struct page *upg = (vma && vma->vm_mm) ?
163 				follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
164 				: NULL;
165 			dump_one_vdso_page(pg, upg);
166 		}
167 	}
168 	if (!vma || !test_thread_flag(TIF_32BIT)) {
169 		printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
170 		for (i=0; i<vdso64_pages; i++) {
171 			struct page *pg = virt_to_page(vdso64_kbase +
172 						       i*PAGE_SIZE);
173 			struct page *upg = (vma && vma->vm_mm) ?
174 				follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
175 				: NULL;
176 			dump_one_vdso_page(pg, upg);
177 		}
178 	}
179 }
180 #endif /* DEBUG */
181 
182 /*
183  * This is called from binfmt_elf, we create the special vma for the
184  * vDSO and insert it into the mm struct tree
185  */
186 int arch_setup_additional_pages(struct linux_binprm *bprm,
187 				int executable_stack)
188 {
189 	struct mm_struct *mm = current->mm;
190 	struct page **vdso_pagelist;
191 	unsigned long vdso_pages;
192 	unsigned long vdso_base;
193 	int rc;
194 
195 	if (!vdso_ready)
196 		return 0;
197 
198 #ifdef CONFIG_PPC64
199 	if (test_thread_flag(TIF_32BIT)) {
200 		vdso_pagelist = vdso32_pagelist;
201 		vdso_pages = vdso32_pages;
202 		vdso_base = VDSO32_MBASE;
203 	} else {
204 		vdso_pagelist = vdso64_pagelist;
205 		vdso_pages = vdso64_pages;
206 		vdso_base = VDSO64_MBASE;
207 	}
208 #else
209 	vdso_pagelist = vdso32_pagelist;
210 	vdso_pages = vdso32_pages;
211 	vdso_base = VDSO32_MBASE;
212 #endif
213 
214 	current->mm->context.vdso_base = 0;
215 
216 	/* vDSO has a problem and was disabled, just don't "enable" it for the
217 	 * process
218 	 */
219 	if (vdso_pages == 0)
220 		return 0;
221 	/* Add a page to the vdso size for the data page */
222 	vdso_pages ++;
223 
224 	/*
225 	 * pick a base address for the vDSO in process space. We try to put it
226 	 * at vdso_base which is the "natural" base for it, but we might fail
227 	 * and end up putting it elsewhere.
228 	 */
229 	down_write(&mm->mmap_sem);
230 	vdso_base = get_unmapped_area(NULL, vdso_base,
231 				      vdso_pages << PAGE_SHIFT, 0, 0);
232 	if (IS_ERR_VALUE(vdso_base)) {
233 		rc = vdso_base;
234 		goto fail_mmapsem;
235 	}
236 
237 	/*
238 	 * our vma flags don't have VM_WRITE so by default, the process isn't
239 	 * allowed to write those pages.
240 	 * gdb can break that with ptrace interface, and thus trigger COW on
241 	 * those pages but it's then your responsibility to never do that on
242 	 * the "data" page of the vDSO or you'll stop getting kernel updates
243 	 * and your nice userland gettimeofday will be totally dead.
244 	 * It's fine to use that for setting breakpoints in the vDSO code
245 	 * pages though
246 	 *
247 	 * Make sure the vDSO gets into every core dump.
248 	 * Dumping its contents makes post-mortem fully interpretable later
249 	 * without matching up the same kernel and hardware config to see
250 	 * what PC values meant.
251 	 */
252 	rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
253 				     VM_READ|VM_EXEC|
254 				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
255 				     VM_ALWAYSDUMP,
256 				     vdso_pagelist);
257 	if (rc)
258 		goto fail_mmapsem;
259 
260 	/* Put vDSO base into mm struct */
261 	current->mm->context.vdso_base = vdso_base;
262 
263 	up_write(&mm->mmap_sem);
264 	return 0;
265 
266  fail_mmapsem:
267 	up_write(&mm->mmap_sem);
268 	return rc;
269 }
270 
271 const char *arch_vma_name(struct vm_area_struct *vma)
272 {
273 	if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
274 		return "[vdso]";
275 	return NULL;
276 }
277 
278 
279 
280 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
281 				  unsigned long *size)
282 {
283 	Elf32_Shdr *sechdrs;
284 	unsigned int i;
285 	char *secnames;
286 
287 	/* Grab section headers and strings so we can tell who is who */
288 	sechdrs = (void *)ehdr + ehdr->e_shoff;
289 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
290 
291 	/* Find the section they want */
292 	for (i = 1; i < ehdr->e_shnum; i++) {
293 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
294 			if (size)
295 				*size = sechdrs[i].sh_size;
296 			return (void *)ehdr + sechdrs[i].sh_offset;
297 		}
298 	}
299 	*size = 0;
300 	return NULL;
301 }
302 
303 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
304 					const char *symname)
305 {
306 	unsigned int i;
307 	char name[MAX_SYMNAME], *c;
308 
309 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
310 		if (lib->dynsym[i].st_name == 0)
311 			continue;
312 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
313 			MAX_SYMNAME);
314 		c = strchr(name, '@');
315 		if (c)
316 			*c = 0;
317 		if (strcmp(symname, name) == 0)
318 			return &lib->dynsym[i];
319 	}
320 	return NULL;
321 }
322 
323 /* Note that we assume the section is .text and the symbol is relative to
324  * the library base
325  */
326 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
327 					    const char *symname)
328 {
329 	Elf32_Sym *sym = find_symbol32(lib, symname);
330 
331 	if (sym == NULL) {
332 		printk(KERN_WARNING "vDSO32: function %s not found !\n",
333 		       symname);
334 		return 0;
335 	}
336 	return sym->st_value - VDSO32_LBASE;
337 }
338 
339 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
340 				struct lib64_elfinfo *v64,
341 				const char *orig, const char *fix)
342 {
343 	Elf32_Sym *sym32_gen, *sym32_fix;
344 
345 	sym32_gen = find_symbol32(v32, orig);
346 	if (sym32_gen == NULL) {
347 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
348 		return -1;
349 	}
350 	if (fix == NULL) {
351 		sym32_gen->st_name = 0;
352 		return 0;
353 	}
354 	sym32_fix = find_symbol32(v32, fix);
355 	if (sym32_fix == NULL) {
356 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
357 		return -1;
358 	}
359 	sym32_gen->st_value = sym32_fix->st_value;
360 	sym32_gen->st_size = sym32_fix->st_size;
361 	sym32_gen->st_info = sym32_fix->st_info;
362 	sym32_gen->st_other = sym32_fix->st_other;
363 	sym32_gen->st_shndx = sym32_fix->st_shndx;
364 
365 	return 0;
366 }
367 
368 
369 #ifdef CONFIG_PPC64
370 
371 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
372 				  unsigned long *size)
373 {
374 	Elf64_Shdr *sechdrs;
375 	unsigned int i;
376 	char *secnames;
377 
378 	/* Grab section headers and strings so we can tell who is who */
379 	sechdrs = (void *)ehdr + ehdr->e_shoff;
380 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
381 
382 	/* Find the section they want */
383 	for (i = 1; i < ehdr->e_shnum; i++) {
384 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
385 			if (size)
386 				*size = sechdrs[i].sh_size;
387 			return (void *)ehdr + sechdrs[i].sh_offset;
388 		}
389 	}
390 	if (size)
391 		*size = 0;
392 	return NULL;
393 }
394 
395 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
396 					const char *symname)
397 {
398 	unsigned int i;
399 	char name[MAX_SYMNAME], *c;
400 
401 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
402 		if (lib->dynsym[i].st_name == 0)
403 			continue;
404 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
405 			MAX_SYMNAME);
406 		c = strchr(name, '@');
407 		if (c)
408 			*c = 0;
409 		if (strcmp(symname, name) == 0)
410 			return &lib->dynsym[i];
411 	}
412 	return NULL;
413 }
414 
415 /* Note that we assume the section is .text and the symbol is relative to
416  * the library base
417  */
418 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
419 					    const char *symname)
420 {
421 	Elf64_Sym *sym = find_symbol64(lib, symname);
422 
423 	if (sym == NULL) {
424 		printk(KERN_WARNING "vDSO64: function %s not found !\n",
425 		       symname);
426 		return 0;
427 	}
428 #ifdef VDS64_HAS_DESCRIPTORS
429 	return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
430 		VDSO64_LBASE;
431 #else
432 	return sym->st_value - VDSO64_LBASE;
433 #endif
434 }
435 
436 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
437 				struct lib64_elfinfo *v64,
438 				const char *orig, const char *fix)
439 {
440 	Elf64_Sym *sym64_gen, *sym64_fix;
441 
442 	sym64_gen = find_symbol64(v64, orig);
443 	if (sym64_gen == NULL) {
444 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
445 		return -1;
446 	}
447 	if (fix == NULL) {
448 		sym64_gen->st_name = 0;
449 		return 0;
450 	}
451 	sym64_fix = find_symbol64(v64, fix);
452 	if (sym64_fix == NULL) {
453 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
454 		return -1;
455 	}
456 	sym64_gen->st_value = sym64_fix->st_value;
457 	sym64_gen->st_size = sym64_fix->st_size;
458 	sym64_gen->st_info = sym64_fix->st_info;
459 	sym64_gen->st_other = sym64_fix->st_other;
460 	sym64_gen->st_shndx = sym64_fix->st_shndx;
461 
462 	return 0;
463 }
464 
465 #endif /* CONFIG_PPC64 */
466 
467 
468 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
469 					struct lib64_elfinfo *v64)
470 {
471 	void *sect;
472 
473 	/*
474 	 * Locate symbol tables & text section
475 	 */
476 
477 	v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
478 	v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
479 	if (v32->dynsym == NULL || v32->dynstr == NULL) {
480 		printk(KERN_ERR "vDSO32: required symbol section not found\n");
481 		return -1;
482 	}
483 	sect = find_section32(v32->hdr, ".text", NULL);
484 	if (sect == NULL) {
485 		printk(KERN_ERR "vDSO32: the .text section was not found\n");
486 		return -1;
487 	}
488 	v32->text = sect - vdso32_kbase;
489 
490 #ifdef CONFIG_PPC64
491 	v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
492 	v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
493 	if (v64->dynsym == NULL || v64->dynstr == NULL) {
494 		printk(KERN_ERR "vDSO64: required symbol section not found\n");
495 		return -1;
496 	}
497 	sect = find_section64(v64->hdr, ".text", NULL);
498 	if (sect == NULL) {
499 		printk(KERN_ERR "vDSO64: the .text section was not found\n");
500 		return -1;
501 	}
502 	v64->text = sect - vdso64_kbase;
503 #endif /* CONFIG_PPC64 */
504 
505 	return 0;
506 }
507 
508 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
509 					  struct lib64_elfinfo *v64)
510 {
511 	/*
512 	 * Find signal trampolines
513 	 */
514 
515 #ifdef CONFIG_PPC64
516 	vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
517 #endif
518 	vdso32_sigtramp	   = find_function32(v32, "__kernel_sigtramp32");
519 	vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
520 }
521 
522 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
523 				       struct lib64_elfinfo *v64)
524 {
525 	Elf32_Sym *sym32;
526 #ifdef CONFIG_PPC64
527 	Elf64_Sym *sym64;
528 
529        	sym64 = find_symbol64(v64, "__kernel_datapage_offset");
530 	if (sym64 == NULL) {
531 		printk(KERN_ERR "vDSO64: Can't find symbol "
532 		       "__kernel_datapage_offset !\n");
533 		return -1;
534 	}
535 	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
536 		(vdso64_pages << PAGE_SHIFT) -
537 		(sym64->st_value - VDSO64_LBASE);
538 #endif /* CONFIG_PPC64 */
539 
540 	sym32 = find_symbol32(v32, "__kernel_datapage_offset");
541 	if (sym32 == NULL) {
542 		printk(KERN_ERR "vDSO32: Can't find symbol "
543 		       "__kernel_datapage_offset !\n");
544 		return -1;
545 	}
546 	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
547 		(vdso32_pages << PAGE_SHIFT) -
548 		(sym32->st_value - VDSO32_LBASE);
549 
550 	return 0;
551 }
552 
553 
554 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
555 				      struct lib64_elfinfo *v64)
556 {
557 	void *start32;
558 	unsigned long size32;
559 
560 #ifdef CONFIG_PPC64
561 	void *start64;
562 	unsigned long size64;
563 
564 	start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
565 	if (start64)
566 		do_feature_fixups(cur_cpu_spec->cpu_features,
567 				  start64, start64 + size64);
568 
569 	start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
570 	if (start64)
571 		do_feature_fixups(powerpc_firmware_features,
572 				  start64, start64 + size64);
573 #endif /* CONFIG_PPC64 */
574 
575 	start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
576 	if (start32)
577 		do_feature_fixups(cur_cpu_spec->cpu_features,
578 				  start32, start32 + size32);
579 
580 #ifdef CONFIG_PPC64
581 	start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
582 	if (start32)
583 		do_feature_fixups(powerpc_firmware_features,
584 				  start32, start32 + size32);
585 #endif /* CONFIG_PPC64 */
586 
587 	return 0;
588 }
589 
590 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
591 				       struct lib64_elfinfo *v64)
592 {
593 	int i;
594 
595 	for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
596 		struct vdso_patch_def *patch = &vdso_patches[i];
597 		int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
598 			== patch->ftr_value;
599 		if (!match)
600 			continue;
601 
602 		DBG("replacing %s with %s...\n", patch->gen_name,
603 		    patch->fix_name ? "NONE" : patch->fix_name);
604 
605 		/*
606 		 * Patch the 32 bits and 64 bits symbols. Note that we do not
607 		 * patch the "." symbol on 64 bits.
608 		 * It would be easy to do, but doesn't seem to be necessary,
609 		 * patching the OPD symbol is enough.
610 		 */
611 		vdso_do_func_patch32(v32, v64, patch->gen_name,
612 				     patch->fix_name);
613 #ifdef CONFIG_PPC64
614 		vdso_do_func_patch64(v32, v64, patch->gen_name,
615 				     patch->fix_name);
616 #endif /* CONFIG_PPC64 */
617 	}
618 
619 	return 0;
620 }
621 
622 
623 static __init int vdso_setup(void)
624 {
625 	struct lib32_elfinfo	v32;
626 	struct lib64_elfinfo	v64;
627 
628 	v32.hdr = vdso32_kbase;
629 #ifdef CONFIG_PPC64
630 	v64.hdr = vdso64_kbase;
631 #endif
632 	if (vdso_do_find_sections(&v32, &v64))
633 		return -1;
634 
635 	if (vdso_fixup_datapage(&v32, &v64))
636 		return -1;
637 
638 	if (vdso_fixup_features(&v32, &v64))
639 		return -1;
640 
641 	if (vdso_fixup_alt_funcs(&v32, &v64))
642 		return -1;
643 
644 	vdso_setup_trampolines(&v32, &v64);
645 
646 	return 0;
647 }
648 
649 /*
650  * Called from setup_arch to initialize the bitmap of available
651  * syscalls in the systemcfg page
652  */
653 static void __init vdso_setup_syscall_map(void)
654 {
655 	unsigned int i;
656 	extern unsigned long *sys_call_table;
657 	extern unsigned long sys_ni_syscall;
658 
659 
660 	for (i = 0; i < __NR_syscalls; i++) {
661 #ifdef CONFIG_PPC64
662 		if (sys_call_table[i*2] != sys_ni_syscall)
663 			vdso_data->syscall_map_64[i >> 5] |=
664 				0x80000000UL >> (i & 0x1f);
665 		if (sys_call_table[i*2+1] != sys_ni_syscall)
666 			vdso_data->syscall_map_32[i >> 5] |=
667 				0x80000000UL >> (i & 0x1f);
668 #else /* CONFIG_PPC64 */
669 		if (sys_call_table[i] != sys_ni_syscall)
670 			vdso_data->syscall_map_32[i >> 5] |=
671 				0x80000000UL >> (i & 0x1f);
672 #endif /* CONFIG_PPC64 */
673 	}
674 }
675 
676 
677 static int __init vdso_init(void)
678 {
679 	int i;
680 
681 #ifdef CONFIG_PPC64
682 	/*
683 	 * Fill up the "systemcfg" stuff for backward compatiblity
684 	 */
685 	strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
686 	vdso_data->version.major = SYSTEMCFG_MAJOR;
687 	vdso_data->version.minor = SYSTEMCFG_MINOR;
688 	vdso_data->processor = mfspr(SPRN_PVR);
689 	/*
690 	 * Fake the old platform number for pSeries and iSeries and add
691 	 * in LPAR bit if necessary
692 	 */
693 	vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
694 	if (firmware_has_feature(FW_FEATURE_LPAR))
695 		vdso_data->platform |= 1;
696 	vdso_data->physicalMemorySize = lmb_phys_mem_size();
697 	vdso_data->dcache_size = ppc64_caches.dsize;
698 	vdso_data->dcache_line_size = ppc64_caches.dline_size;
699 	vdso_data->icache_size = ppc64_caches.isize;
700 	vdso_data->icache_line_size = ppc64_caches.iline_size;
701 
702 	/*
703 	 * Calculate the size of the 64 bits vDSO
704 	 */
705 	vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
706 	DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
707 #endif /* CONFIG_PPC64 */
708 
709 
710 	/*
711 	 * Calculate the size of the 32 bits vDSO
712 	 */
713 	vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
714 	DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
715 
716 
717 	/*
718 	 * Setup the syscall map in the vDOS
719 	 */
720 	vdso_setup_syscall_map();
721 
722 	/*
723 	 * Initialize the vDSO images in memory, that is do necessary
724 	 * fixups of vDSO symbols, locate trampolines, etc...
725 	 */
726 	if (vdso_setup()) {
727 		printk(KERN_ERR "vDSO setup failure, not enabled !\n");
728 		vdso32_pages = 0;
729 #ifdef CONFIG_PPC64
730 		vdso64_pages = 0;
731 #endif
732 		return 0;
733 	}
734 
735 	/* Make sure pages are in the correct state */
736 	vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
737 				  GFP_KERNEL);
738 	BUG_ON(vdso32_pagelist == NULL);
739 	for (i = 0; i < vdso32_pages; i++) {
740 		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
741 		ClearPageReserved(pg);
742 		get_page(pg);
743 		vdso32_pagelist[i] = pg;
744 	}
745 	vdso32_pagelist[i++] = virt_to_page(vdso_data);
746 	vdso32_pagelist[i] = NULL;
747 
748 #ifdef CONFIG_PPC64
749 	vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
750 				  GFP_KERNEL);
751 	BUG_ON(vdso64_pagelist == NULL);
752 	for (i = 0; i < vdso64_pages; i++) {
753 		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
754 		ClearPageReserved(pg);
755 		get_page(pg);
756 		vdso64_pagelist[i] = pg;
757 	}
758 	vdso64_pagelist[i++] = virt_to_page(vdso_data);
759 	vdso64_pagelist[i] = NULL;
760 #endif /* CONFIG_PPC64 */
761 
762 	get_page(virt_to_page(vdso_data));
763 
764 	smp_wmb();
765 	vdso_ready = 1;
766 
767 	return 0;
768 }
769 #ifdef CONFIG_PPC_MERGE
770 arch_initcall(vdso_init);
771 #endif
772 
773 int in_gate_area_no_task(unsigned long addr)
774 {
775 	return 0;
776 }
777 
778 int in_gate_area(struct task_struct *task, unsigned long addr)
779 {
780 	return 0;
781 }
782 
783 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
784 {
785 	return NULL;
786 }
787 
788