xref: /openbmc/linux/arch/powerpc/kernel/vdso.c (revision e8e0929d)
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/module.h>
13 #include <linux/errno.h>
14 #include <linux/sched.h>
15 #include <linux/kernel.h>
16 #include <linux/mm.h>
17 #include <linux/smp.h>
18 #include <linux/stddef.h>
19 #include <linux/unistd.h>
20 #include <linux/slab.h>
21 #include <linux/user.h>
22 #include <linux/elf.h>
23 #include <linux/security.h>
24 #include <linux/bootmem.h>
25 #include <linux/lmb.h>
26 
27 #include <asm/pgtable.h>
28 #include <asm/system.h>
29 #include <asm/processor.h>
30 #include <asm/mmu.h>
31 #include <asm/mmu_context.h>
32 #include <asm/prom.h>
33 #include <asm/machdep.h>
34 #include <asm/cputable.h>
35 #include <asm/sections.h>
36 #include <asm/firmware.h>
37 #include <asm/vdso.h>
38 #include <asm/vdso_datapage.h>
39 
40 #include "setup.h"
41 
42 #undef DEBUG
43 
44 #ifdef DEBUG
45 #define DBG(fmt...) printk(fmt)
46 #else
47 #define DBG(fmt...)
48 #endif
49 
50 /* Max supported size for symbol names */
51 #define MAX_SYMNAME	64
52 
53 extern char vdso32_start, vdso32_end;
54 static void *vdso32_kbase = &vdso32_start;
55 static unsigned int vdso32_pages;
56 static struct page **vdso32_pagelist;
57 unsigned long vdso32_sigtramp;
58 unsigned long vdso32_rt_sigtramp;
59 
60 #ifdef CONFIG_PPC64
61 extern char vdso64_start, vdso64_end;
62 static void *vdso64_kbase = &vdso64_start;
63 static unsigned int vdso64_pages;
64 static struct page **vdso64_pagelist;
65 unsigned long vdso64_rt_sigtramp;
66 #endif /* CONFIG_PPC64 */
67 
68 static int vdso_ready;
69 
70 /*
71  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
72  * Once the early boot kernel code no longer needs to muck around
73  * with it, it will become dynamically allocated
74  */
75 static union {
76 	struct vdso_data	data;
77 	u8			page[PAGE_SIZE];
78 } vdso_data_store __page_aligned_data;
79 struct vdso_data *vdso_data = &vdso_data_store.data;
80 
81 /* Format of the patch table */
82 struct vdso_patch_def
83 {
84 	unsigned long	ftr_mask, ftr_value;
85 	const char	*gen_name;
86 	const char	*fix_name;
87 };
88 
89 /* Table of functions to patch based on the CPU type/revision
90  *
91  * Currently, we only change sync_dicache to do nothing on processors
92  * with a coherent icache
93  */
94 static struct vdso_patch_def vdso_patches[] = {
95 	{
96 		CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
97 		"__kernel_sync_dicache", "__kernel_sync_dicache_p5"
98 	},
99 	{
100 		CPU_FTR_USE_TB, 0,
101 		"__kernel_gettimeofday", NULL
102 	},
103 	{
104 		CPU_FTR_USE_TB, 0,
105 		"__kernel_clock_gettime", NULL
106 	},
107 	{
108 		CPU_FTR_USE_TB, 0,
109 		"__kernel_clock_getres", NULL
110 	},
111 	{
112 		CPU_FTR_USE_TB, 0,
113 		"__kernel_get_tbfreq", NULL
114 	},
115 };
116 
117 /*
118  * Some infos carried around for each of them during parsing at
119  * boot time.
120  */
121 struct lib32_elfinfo
122 {
123 	Elf32_Ehdr	*hdr;		/* ptr to ELF */
124 	Elf32_Sym	*dynsym;	/* ptr to .dynsym section */
125 	unsigned long	dynsymsize;	/* size of .dynsym section */
126 	char		*dynstr;	/* ptr to .dynstr section */
127 	unsigned long	text;		/* offset of .text section in .so */
128 };
129 
130 struct lib64_elfinfo
131 {
132 	Elf64_Ehdr	*hdr;
133 	Elf64_Sym	*dynsym;
134 	unsigned long	dynsymsize;
135 	char		*dynstr;
136 	unsigned long	text;
137 };
138 
139 
140 #ifdef __DEBUG
141 static void dump_one_vdso_page(struct page *pg, struct page *upg)
142 {
143 	printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
144 	       page_count(pg),
145 	       pg->flags);
146 	if (upg && !IS_ERR(upg) /* && pg != upg*/) {
147 		printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
148 						       << PAGE_SHIFT),
149 		       page_count(upg),
150 		       upg->flags);
151 	}
152 	printk("\n");
153 }
154 
155 static void dump_vdso_pages(struct vm_area_struct * vma)
156 {
157 	int i;
158 
159 	if (!vma || test_thread_flag(TIF_32BIT)) {
160 		printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
161 		for (i=0; i<vdso32_pages; i++) {
162 			struct page *pg = virt_to_page(vdso32_kbase +
163 						       i*PAGE_SIZE);
164 			struct page *upg = (vma && vma->vm_mm) ?
165 				follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
166 				: NULL;
167 			dump_one_vdso_page(pg, upg);
168 		}
169 	}
170 	if (!vma || !test_thread_flag(TIF_32BIT)) {
171 		printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
172 		for (i=0; i<vdso64_pages; i++) {
173 			struct page *pg = virt_to_page(vdso64_kbase +
174 						       i*PAGE_SIZE);
175 			struct page *upg = (vma && vma->vm_mm) ?
176 				follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
177 				: NULL;
178 			dump_one_vdso_page(pg, upg);
179 		}
180 	}
181 }
182 #endif /* DEBUG */
183 
184 /*
185  * This is called from binfmt_elf, we create the special vma for the
186  * vDSO and insert it into the mm struct tree
187  */
188 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
189 {
190 	struct mm_struct *mm = current->mm;
191 	struct page **vdso_pagelist;
192 	unsigned long vdso_pages;
193 	unsigned long vdso_base;
194 	int rc;
195 
196 	if (!vdso_ready)
197 		return 0;
198 
199 #ifdef CONFIG_PPC64
200 	if (test_thread_flag(TIF_32BIT)) {
201 		vdso_pagelist = vdso32_pagelist;
202 		vdso_pages = vdso32_pages;
203 		vdso_base = VDSO32_MBASE;
204 	} else {
205 		vdso_pagelist = vdso64_pagelist;
206 		vdso_pages = vdso64_pages;
207 		/*
208 		 * On 64bit we don't have a preferred map address. This
209 		 * allows get_unmapped_area to find an area near other mmaps
210 		 * and most likely share a SLB entry.
211 		 */
212 		vdso_base = 0;
213 	}
214 #else
215 	vdso_pagelist = vdso32_pagelist;
216 	vdso_pages = vdso32_pages;
217 	vdso_base = VDSO32_MBASE;
218 #endif
219 
220 	current->mm->context.vdso_base = 0;
221 
222 	/* vDSO has a problem and was disabled, just don't "enable" it for the
223 	 * process
224 	 */
225 	if (vdso_pages == 0)
226 		return 0;
227 	/* Add a page to the vdso size for the data page */
228 	vdso_pages ++;
229 
230 	/*
231 	 * pick a base address for the vDSO in process space. We try to put it
232 	 * at vdso_base which is the "natural" base for it, but we might fail
233 	 * and end up putting it elsewhere.
234 	 */
235 	down_write(&mm->mmap_sem);
236 	vdso_base = get_unmapped_area(NULL, vdso_base,
237 				      vdso_pages << PAGE_SHIFT, 0, 0);
238 	if (IS_ERR_VALUE(vdso_base)) {
239 		rc = vdso_base;
240 		goto fail_mmapsem;
241 	}
242 
243 	/*
244 	 * Put vDSO base into mm struct. We need to do this before calling
245 	 * install_special_mapping or the perf counter mmap tracking code
246 	 * will fail to recognise it as a vDSO (since arch_vma_name fails).
247 	 */
248 	current->mm->context.vdso_base = vdso_base;
249 
250 	/*
251 	 * our vma flags don't have VM_WRITE so by default, the process isn't
252 	 * allowed to write those pages.
253 	 * gdb can break that with ptrace interface, and thus trigger COW on
254 	 * those pages but it's then your responsibility to never do that on
255 	 * the "data" page of the vDSO or you'll stop getting kernel updates
256 	 * and your nice userland gettimeofday will be totally dead.
257 	 * It's fine to use that for setting breakpoints in the vDSO code
258 	 * pages though
259 	 *
260 	 * Make sure the vDSO gets into every core dump.
261 	 * Dumping its contents makes post-mortem fully interpretable later
262 	 * without matching up the same kernel and hardware config to see
263 	 * what PC values meant.
264 	 */
265 	rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
266 				     VM_READ|VM_EXEC|
267 				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
268 				     VM_ALWAYSDUMP,
269 				     vdso_pagelist);
270 	if (rc) {
271 		current->mm->context.vdso_base = 0;
272 		goto fail_mmapsem;
273 	}
274 
275 	up_write(&mm->mmap_sem);
276 	return 0;
277 
278  fail_mmapsem:
279 	up_write(&mm->mmap_sem);
280 	return rc;
281 }
282 
283 const char *arch_vma_name(struct vm_area_struct *vma)
284 {
285 	if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
286 		return "[vdso]";
287 	return NULL;
288 }
289 
290 
291 
292 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
293 				  unsigned long *size)
294 {
295 	Elf32_Shdr *sechdrs;
296 	unsigned int i;
297 	char *secnames;
298 
299 	/* Grab section headers and strings so we can tell who is who */
300 	sechdrs = (void *)ehdr + ehdr->e_shoff;
301 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
302 
303 	/* Find the section they want */
304 	for (i = 1; i < ehdr->e_shnum; i++) {
305 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
306 			if (size)
307 				*size = sechdrs[i].sh_size;
308 			return (void *)ehdr + sechdrs[i].sh_offset;
309 		}
310 	}
311 	*size = 0;
312 	return NULL;
313 }
314 
315 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
316 					const char *symname)
317 {
318 	unsigned int i;
319 	char name[MAX_SYMNAME], *c;
320 
321 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
322 		if (lib->dynsym[i].st_name == 0)
323 			continue;
324 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
325 			MAX_SYMNAME);
326 		c = strchr(name, '@');
327 		if (c)
328 			*c = 0;
329 		if (strcmp(symname, name) == 0)
330 			return &lib->dynsym[i];
331 	}
332 	return NULL;
333 }
334 
335 /* Note that we assume the section is .text and the symbol is relative to
336  * the library base
337  */
338 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
339 					    const char *symname)
340 {
341 	Elf32_Sym *sym = find_symbol32(lib, symname);
342 
343 	if (sym == NULL) {
344 		printk(KERN_WARNING "vDSO32: function %s not found !\n",
345 		       symname);
346 		return 0;
347 	}
348 	return sym->st_value - VDSO32_LBASE;
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 	Elf32_Sym *sym32_gen, *sym32_fix;
356 
357 	sym32_gen = find_symbol32(v32, orig);
358 	if (sym32_gen == NULL) {
359 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
360 		return -1;
361 	}
362 	if (fix == NULL) {
363 		sym32_gen->st_name = 0;
364 		return 0;
365 	}
366 	sym32_fix = find_symbol32(v32, fix);
367 	if (sym32_fix == NULL) {
368 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
369 		return -1;
370 	}
371 	sym32_gen->st_value = sym32_fix->st_value;
372 	sym32_gen->st_size = sym32_fix->st_size;
373 	sym32_gen->st_info = sym32_fix->st_info;
374 	sym32_gen->st_other = sym32_fix->st_other;
375 	sym32_gen->st_shndx = sym32_fix->st_shndx;
376 
377 	return 0;
378 }
379 
380 
381 #ifdef CONFIG_PPC64
382 
383 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
384 				  unsigned long *size)
385 {
386 	Elf64_Shdr *sechdrs;
387 	unsigned int i;
388 	char *secnames;
389 
390 	/* Grab section headers and strings so we can tell who is who */
391 	sechdrs = (void *)ehdr + ehdr->e_shoff;
392 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
393 
394 	/* Find the section they want */
395 	for (i = 1; i < ehdr->e_shnum; i++) {
396 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
397 			if (size)
398 				*size = sechdrs[i].sh_size;
399 			return (void *)ehdr + sechdrs[i].sh_offset;
400 		}
401 	}
402 	if (size)
403 		*size = 0;
404 	return NULL;
405 }
406 
407 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
408 					const char *symname)
409 {
410 	unsigned int i;
411 	char name[MAX_SYMNAME], *c;
412 
413 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
414 		if (lib->dynsym[i].st_name == 0)
415 			continue;
416 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
417 			MAX_SYMNAME);
418 		c = strchr(name, '@');
419 		if (c)
420 			*c = 0;
421 		if (strcmp(symname, name) == 0)
422 			return &lib->dynsym[i];
423 	}
424 	return NULL;
425 }
426 
427 /* Note that we assume the section is .text and the symbol is relative to
428  * the library base
429  */
430 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
431 					    const char *symname)
432 {
433 	Elf64_Sym *sym = find_symbol64(lib, symname);
434 
435 	if (sym == NULL) {
436 		printk(KERN_WARNING "vDSO64: function %s not found !\n",
437 		       symname);
438 		return 0;
439 	}
440 #ifdef VDS64_HAS_DESCRIPTORS
441 	return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
442 		VDSO64_LBASE;
443 #else
444 	return sym->st_value - VDSO64_LBASE;
445 #endif
446 }
447 
448 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
449 				       struct lib64_elfinfo *v64,
450 				       const char *orig, const char *fix)
451 {
452 	Elf64_Sym *sym64_gen, *sym64_fix;
453 
454 	sym64_gen = find_symbol64(v64, orig);
455 	if (sym64_gen == NULL) {
456 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
457 		return -1;
458 	}
459 	if (fix == NULL) {
460 		sym64_gen->st_name = 0;
461 		return 0;
462 	}
463 	sym64_fix = find_symbol64(v64, fix);
464 	if (sym64_fix == NULL) {
465 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
466 		return -1;
467 	}
468 	sym64_gen->st_value = sym64_fix->st_value;
469 	sym64_gen->st_size = sym64_fix->st_size;
470 	sym64_gen->st_info = sym64_fix->st_info;
471 	sym64_gen->st_other = sym64_fix->st_other;
472 	sym64_gen->st_shndx = sym64_fix->st_shndx;
473 
474 	return 0;
475 }
476 
477 #endif /* CONFIG_PPC64 */
478 
479 
480 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
481 					struct lib64_elfinfo *v64)
482 {
483 	void *sect;
484 
485 	/*
486 	 * Locate symbol tables & text section
487 	 */
488 
489 	v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
490 	v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
491 	if (v32->dynsym == NULL || v32->dynstr == NULL) {
492 		printk(KERN_ERR "vDSO32: required symbol section not found\n");
493 		return -1;
494 	}
495 	sect = find_section32(v32->hdr, ".text", NULL);
496 	if (sect == NULL) {
497 		printk(KERN_ERR "vDSO32: the .text section was not found\n");
498 		return -1;
499 	}
500 	v32->text = sect - vdso32_kbase;
501 
502 #ifdef CONFIG_PPC64
503 	v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
504 	v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
505 	if (v64->dynsym == NULL || v64->dynstr == NULL) {
506 		printk(KERN_ERR "vDSO64: required symbol section not found\n");
507 		return -1;
508 	}
509 	sect = find_section64(v64->hdr, ".text", NULL);
510 	if (sect == NULL) {
511 		printk(KERN_ERR "vDSO64: the .text section was not found\n");
512 		return -1;
513 	}
514 	v64->text = sect - vdso64_kbase;
515 #endif /* CONFIG_PPC64 */
516 
517 	return 0;
518 }
519 
520 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
521 					  struct lib64_elfinfo *v64)
522 {
523 	/*
524 	 * Find signal trampolines
525 	 */
526 
527 #ifdef CONFIG_PPC64
528 	vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
529 #endif
530 	vdso32_sigtramp	   = find_function32(v32, "__kernel_sigtramp32");
531 	vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
532 }
533 
534 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
535 				       struct lib64_elfinfo *v64)
536 {
537 	Elf32_Sym *sym32;
538 #ifdef CONFIG_PPC64
539 	Elf64_Sym *sym64;
540 
541        	sym64 = find_symbol64(v64, "__kernel_datapage_offset");
542 	if (sym64 == NULL) {
543 		printk(KERN_ERR "vDSO64: Can't find symbol "
544 		       "__kernel_datapage_offset !\n");
545 		return -1;
546 	}
547 	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
548 		(vdso64_pages << PAGE_SHIFT) -
549 		(sym64->st_value - VDSO64_LBASE);
550 #endif /* CONFIG_PPC64 */
551 
552 	sym32 = find_symbol32(v32, "__kernel_datapage_offset");
553 	if (sym32 == NULL) {
554 		printk(KERN_ERR "vDSO32: Can't find symbol "
555 		       "__kernel_datapage_offset !\n");
556 		return -1;
557 	}
558 	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
559 		(vdso32_pages << PAGE_SHIFT) -
560 		(sym32->st_value - VDSO32_LBASE);
561 
562 	return 0;
563 }
564 
565 
566 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
567 				      struct lib64_elfinfo *v64)
568 {
569 	void *start32;
570 	unsigned long size32;
571 
572 #ifdef CONFIG_PPC64
573 	void *start64;
574 	unsigned long size64;
575 
576 	start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
577 	if (start64)
578 		do_feature_fixups(cur_cpu_spec->cpu_features,
579 				  start64, start64 + size64);
580 
581 	start64 = find_section64(v64->hdr, "__mmu_ftr_fixup", &size64);
582 	if (start64)
583 		do_feature_fixups(cur_cpu_spec->mmu_features,
584 				  start64, start64 + size64);
585 
586 	start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
587 	if (start64)
588 		do_feature_fixups(powerpc_firmware_features,
589 				  start64, start64 + size64);
590 
591 	start64 = find_section64(v64->hdr, "__lwsync_fixup", &size64);
592 	if (start64)
593 		do_lwsync_fixups(cur_cpu_spec->cpu_features,
594 				 start64, start64 + size64);
595 #endif /* CONFIG_PPC64 */
596 
597 	start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
598 	if (start32)
599 		do_feature_fixups(cur_cpu_spec->cpu_features,
600 				  start32, start32 + size32);
601 
602 	start32 = find_section32(v32->hdr, "__mmu_ftr_fixup", &size32);
603 	if (start32)
604 		do_feature_fixups(cur_cpu_spec->mmu_features,
605 				  start32, start32 + size32);
606 
607 #ifdef CONFIG_PPC64
608 	start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
609 	if (start32)
610 		do_feature_fixups(powerpc_firmware_features,
611 				  start32, start32 + size32);
612 #endif /* CONFIG_PPC64 */
613 
614 	start32 = find_section32(v32->hdr, "__lwsync_fixup", &size32);
615 	if (start32)
616 		do_lwsync_fixups(cur_cpu_spec->cpu_features,
617 				 start32, start32 + size32);
618 
619 	return 0;
620 }
621 
622 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
623 				       struct lib64_elfinfo *v64)
624 {
625 	int i;
626 
627 	for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
628 		struct vdso_patch_def *patch = &vdso_patches[i];
629 		int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
630 			== patch->ftr_value;
631 		if (!match)
632 			continue;
633 
634 		DBG("replacing %s with %s...\n", patch->gen_name,
635 		    patch->fix_name ? "NONE" : patch->fix_name);
636 
637 		/*
638 		 * Patch the 32 bits and 64 bits symbols. Note that we do not
639 		 * patch the "." symbol on 64 bits.
640 		 * It would be easy to do, but doesn't seem to be necessary,
641 		 * patching the OPD symbol is enough.
642 		 */
643 		vdso_do_func_patch32(v32, v64, patch->gen_name,
644 				     patch->fix_name);
645 #ifdef CONFIG_PPC64
646 		vdso_do_func_patch64(v32, v64, patch->gen_name,
647 				     patch->fix_name);
648 #endif /* CONFIG_PPC64 */
649 	}
650 
651 	return 0;
652 }
653 
654 
655 static __init int vdso_setup(void)
656 {
657 	struct lib32_elfinfo	v32;
658 	struct lib64_elfinfo	v64;
659 
660 	v32.hdr = vdso32_kbase;
661 #ifdef CONFIG_PPC64
662 	v64.hdr = vdso64_kbase;
663 #endif
664 	if (vdso_do_find_sections(&v32, &v64))
665 		return -1;
666 
667 	if (vdso_fixup_datapage(&v32, &v64))
668 		return -1;
669 
670 	if (vdso_fixup_features(&v32, &v64))
671 		return -1;
672 
673 	if (vdso_fixup_alt_funcs(&v32, &v64))
674 		return -1;
675 
676 	vdso_setup_trampolines(&v32, &v64);
677 
678 	return 0;
679 }
680 
681 /*
682  * Called from setup_arch to initialize the bitmap of available
683  * syscalls in the systemcfg page
684  */
685 static void __init vdso_setup_syscall_map(void)
686 {
687 	unsigned int i;
688 	extern unsigned long *sys_call_table;
689 	extern unsigned long sys_ni_syscall;
690 
691 
692 	for (i = 0; i < __NR_syscalls; i++) {
693 #ifdef CONFIG_PPC64
694 		if (sys_call_table[i*2] != sys_ni_syscall)
695 			vdso_data->syscall_map_64[i >> 5] |=
696 				0x80000000UL >> (i & 0x1f);
697 		if (sys_call_table[i*2+1] != sys_ni_syscall)
698 			vdso_data->syscall_map_32[i >> 5] |=
699 				0x80000000UL >> (i & 0x1f);
700 #else /* CONFIG_PPC64 */
701 		if (sys_call_table[i] != sys_ni_syscall)
702 			vdso_data->syscall_map_32[i >> 5] |=
703 				0x80000000UL >> (i & 0x1f);
704 #endif /* CONFIG_PPC64 */
705 	}
706 }
707 
708 
709 static int __init vdso_init(void)
710 {
711 	int i;
712 
713 #ifdef CONFIG_PPC64
714 	/*
715 	 * Fill up the "systemcfg" stuff for backward compatiblity
716 	 */
717 	strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
718 	vdso_data->version.major = SYSTEMCFG_MAJOR;
719 	vdso_data->version.minor = SYSTEMCFG_MINOR;
720 	vdso_data->processor = mfspr(SPRN_PVR);
721 	/*
722 	 * Fake the old platform number for pSeries and iSeries and add
723 	 * in LPAR bit if necessary
724 	 */
725 	vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
726 	if (firmware_has_feature(FW_FEATURE_LPAR))
727 		vdso_data->platform |= 1;
728 	vdso_data->physicalMemorySize = lmb_phys_mem_size();
729 	vdso_data->dcache_size = ppc64_caches.dsize;
730 	vdso_data->dcache_line_size = ppc64_caches.dline_size;
731 	vdso_data->icache_size = ppc64_caches.isize;
732 	vdso_data->icache_line_size = ppc64_caches.iline_size;
733 
734 	/* XXXOJN: Blocks should be added to ppc64_caches and used instead */
735 	vdso_data->dcache_block_size = ppc64_caches.dline_size;
736 	vdso_data->icache_block_size = ppc64_caches.iline_size;
737 	vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
738 	vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
739 
740 	/*
741 	 * Calculate the size of the 64 bits vDSO
742 	 */
743 	vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
744 	DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
745 #else
746 	vdso_data->dcache_block_size = L1_CACHE_BYTES;
747 	vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
748 	vdso_data->icache_block_size = L1_CACHE_BYTES;
749 	vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
750 #endif /* CONFIG_PPC64 */
751 
752 
753 	/*
754 	 * Calculate the size of the 32 bits vDSO
755 	 */
756 	vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
757 	DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
758 
759 
760 	/*
761 	 * Setup the syscall map in the vDOS
762 	 */
763 	vdso_setup_syscall_map();
764 
765 	/*
766 	 * Initialize the vDSO images in memory, that is do necessary
767 	 * fixups of vDSO symbols, locate trampolines, etc...
768 	 */
769 	if (vdso_setup()) {
770 		printk(KERN_ERR "vDSO setup failure, not enabled !\n");
771 		vdso32_pages = 0;
772 #ifdef CONFIG_PPC64
773 		vdso64_pages = 0;
774 #endif
775 		return 0;
776 	}
777 
778 	/* Make sure pages are in the correct state */
779 	vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
780 				  GFP_KERNEL);
781 	BUG_ON(vdso32_pagelist == NULL);
782 	for (i = 0; i < vdso32_pages; i++) {
783 		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
784 		ClearPageReserved(pg);
785 		get_page(pg);
786 		vdso32_pagelist[i] = pg;
787 	}
788 	vdso32_pagelist[i++] = virt_to_page(vdso_data);
789 	vdso32_pagelist[i] = NULL;
790 
791 #ifdef CONFIG_PPC64
792 	vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
793 				  GFP_KERNEL);
794 	BUG_ON(vdso64_pagelist == NULL);
795 	for (i = 0; i < vdso64_pages; i++) {
796 		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
797 		ClearPageReserved(pg);
798 		get_page(pg);
799 		vdso64_pagelist[i] = pg;
800 	}
801 	vdso64_pagelist[i++] = virt_to_page(vdso_data);
802 	vdso64_pagelist[i] = NULL;
803 #endif /* CONFIG_PPC64 */
804 
805 	get_page(virt_to_page(vdso_data));
806 
807 	smp_wmb();
808 	vdso_ready = 1;
809 
810 	return 0;
811 }
812 arch_initcall(vdso_init);
813 
814 int in_gate_area_no_task(unsigned long addr)
815 {
816 	return 0;
817 }
818 
819 int in_gate_area(struct task_struct *task, unsigned long addr)
820 {
821 	return 0;
822 }
823 
824 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
825 {
826 	return NULL;
827 }
828 
829