xref: /linux/arch/powerpc/kernel/vdso.c (revision 9ffc93f203c18a70623f21950f1dd473c9ec48cd)
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/bootmem.h>
24 #include <linux/memblock.h>
25 
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 
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 /* The alignment of the vDSO */
52 #define VDSO_ALIGNMENT	(1 << 16)
53 
54 extern char vdso32_start, vdso32_end;
55 static void *vdso32_kbase = &vdso32_start;
56 static unsigned int vdso32_pages;
57 static struct page **vdso32_pagelist;
58 unsigned long vdso32_sigtramp;
59 unsigned long vdso32_rt_sigtramp;
60 
61 #ifdef CONFIG_PPC64
62 extern char vdso64_start, vdso64_end;
63 static void *vdso64_kbase = &vdso64_start;
64 static unsigned int vdso64_pages;
65 static struct page **vdso64_pagelist;
66 unsigned long vdso64_rt_sigtramp;
67 #endif /* CONFIG_PPC64 */
68 
69 static int vdso_ready;
70 
71 /*
72  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
73  * Once the early boot kernel code no longer needs to muck around
74  * with it, it will become dynamically allocated
75  */
76 static union {
77 	struct vdso_data	data;
78 	u8			page[PAGE_SIZE];
79 } vdso_data_store __page_aligned_data;
80 struct vdso_data *vdso_data = &vdso_data_store.data;
81 
82 /* Format of the patch table */
83 struct vdso_patch_def
84 {
85 	unsigned long	ftr_mask, ftr_value;
86 	const char	*gen_name;
87 	const char	*fix_name;
88 };
89 
90 /* Table of functions to patch based on the CPU type/revision
91  *
92  * Currently, we only change sync_dicache to do nothing on processors
93  * with a coherent icache
94  */
95 static struct vdso_patch_def vdso_patches[] = {
96 	{
97 		CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
98 		"__kernel_sync_dicache", "__kernel_sync_dicache_p5"
99 	},
100 	{
101 		CPU_FTR_USE_TB, 0,
102 		"__kernel_gettimeofday", NULL
103 	},
104 	{
105 		CPU_FTR_USE_TB, 0,
106 		"__kernel_clock_gettime", NULL
107 	},
108 	{
109 		CPU_FTR_USE_TB, 0,
110 		"__kernel_clock_getres", NULL
111 	},
112 	{
113 		CPU_FTR_USE_TB, 0,
114 		"__kernel_get_tbfreq", NULL
115 	},
116 };
117 
118 /*
119  * Some infos carried around for each of them during parsing at
120  * boot time.
121  */
122 struct lib32_elfinfo
123 {
124 	Elf32_Ehdr	*hdr;		/* ptr to ELF */
125 	Elf32_Sym	*dynsym;	/* ptr to .dynsym section */
126 	unsigned long	dynsymsize;	/* size of .dynsym section */
127 	char		*dynstr;	/* ptr to .dynstr section */
128 	unsigned long	text;		/* offset of .text section in .so */
129 };
130 
131 struct lib64_elfinfo
132 {
133 	Elf64_Ehdr	*hdr;
134 	Elf64_Sym	*dynsym;
135 	unsigned long	dynsymsize;
136 	char		*dynstr;
137 	unsigned long	text;
138 };
139 
140 
141 #ifdef __DEBUG
142 static void dump_one_vdso_page(struct page *pg, struct page *upg)
143 {
144 	printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
145 	       page_count(pg),
146 	       pg->flags);
147 	if (upg && !IS_ERR(upg) /* && pg != upg*/) {
148 		printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
149 						       << PAGE_SHIFT),
150 		       page_count(upg),
151 		       upg->flags);
152 	}
153 	printk("\n");
154 }
155 
156 static void dump_vdso_pages(struct vm_area_struct * vma)
157 {
158 	int i;
159 
160 	if (!vma || is_32bit_task()) {
161 		printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
162 		for (i=0; i<vdso32_pages; i++) {
163 			struct page *pg = virt_to_page(vdso32_kbase +
164 						       i*PAGE_SIZE);
165 			struct page *upg = (vma && vma->vm_mm) ?
166 				follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
167 				: NULL;
168 			dump_one_vdso_page(pg, upg);
169 		}
170 	}
171 	if (!vma || !is_32bit_task()) {
172 		printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
173 		for (i=0; i<vdso64_pages; i++) {
174 			struct page *pg = virt_to_page(vdso64_kbase +
175 						       i*PAGE_SIZE);
176 			struct page *upg = (vma && vma->vm_mm) ?
177 				follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
178 				: NULL;
179 			dump_one_vdso_page(pg, upg);
180 		}
181 	}
182 }
183 #endif /* DEBUG */
184 
185 /*
186  * This is called from binfmt_elf, we create the special vma for the
187  * vDSO and insert it into the mm struct tree
188  */
189 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
190 {
191 	struct mm_struct *mm = current->mm;
192 	struct page **vdso_pagelist;
193 	unsigned long vdso_pages;
194 	unsigned long vdso_base;
195 	int rc;
196 
197 	if (!vdso_ready)
198 		return 0;
199 
200 #ifdef CONFIG_PPC64
201 	if (is_32bit_task()) {
202 		vdso_pagelist = vdso32_pagelist;
203 		vdso_pages = vdso32_pages;
204 		vdso_base = VDSO32_MBASE;
205 	} else {
206 		vdso_pagelist = vdso64_pagelist;
207 		vdso_pages = vdso64_pages;
208 		/*
209 		 * On 64bit we don't have a preferred map address. This
210 		 * allows get_unmapped_area to find an area near other mmaps
211 		 * and most likely share a SLB entry.
212 		 */
213 		vdso_base = 0;
214 	}
215 #else
216 	vdso_pagelist = vdso32_pagelist;
217 	vdso_pages = vdso32_pages;
218 	vdso_base = VDSO32_MBASE;
219 #endif
220 
221 	current->mm->context.vdso_base = 0;
222 
223 	/* vDSO has a problem and was disabled, just don't "enable" it for the
224 	 * process
225 	 */
226 	if (vdso_pages == 0)
227 		return 0;
228 	/* Add a page to the vdso size for the data page */
229 	vdso_pages ++;
230 
231 	/*
232 	 * pick a base address for the vDSO in process space. We try to put it
233 	 * at vdso_base which is the "natural" base for it, but we might fail
234 	 * and end up putting it elsewhere.
235 	 * Add enough to the size so that the result can be aligned.
236 	 */
237 	down_write(&mm->mmap_sem);
238 	vdso_base = get_unmapped_area(NULL, vdso_base,
239 				      (vdso_pages << PAGE_SHIFT) +
240 				      ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
241 				      0, 0);
242 	if (IS_ERR_VALUE(vdso_base)) {
243 		rc = vdso_base;
244 		goto fail_mmapsem;
245 	}
246 
247 	/* Add required alignment. */
248 	vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
249 
250 	/*
251 	 * Put vDSO base into mm struct. We need to do this before calling
252 	 * install_special_mapping or the perf counter mmap tracking code
253 	 * will fail to recognise it as a vDSO (since arch_vma_name fails).
254 	 */
255 	current->mm->context.vdso_base = vdso_base;
256 
257 	/*
258 	 * our vma flags don't have VM_WRITE so by default, the process isn't
259 	 * allowed to write those pages.
260 	 * gdb can break that with ptrace interface, and thus trigger COW on
261 	 * those pages but it's then your responsibility to never do that on
262 	 * the "data" page of the vDSO or you'll stop getting kernel updates
263 	 * and your nice userland gettimeofday will be totally dead.
264 	 * It's fine to use that for setting breakpoints in the vDSO code
265 	 * pages though
266 	 *
267 	 * Make sure the vDSO gets into every core dump.
268 	 * Dumping its contents makes post-mortem fully interpretable later
269 	 * without matching up the same kernel and hardware config to see
270 	 * what PC values meant.
271 	 */
272 	rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
273 				     VM_READ|VM_EXEC|
274 				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
275 				     VM_ALWAYSDUMP,
276 				     vdso_pagelist);
277 	if (rc) {
278 		current->mm->context.vdso_base = 0;
279 		goto fail_mmapsem;
280 	}
281 
282 	up_write(&mm->mmap_sem);
283 	return 0;
284 
285  fail_mmapsem:
286 	up_write(&mm->mmap_sem);
287 	return rc;
288 }
289 
290 const char *arch_vma_name(struct vm_area_struct *vma)
291 {
292 	if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
293 		return "[vdso]";
294 	return NULL;
295 }
296 
297 
298 
299 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
300 				  unsigned long *size)
301 {
302 	Elf32_Shdr *sechdrs;
303 	unsigned int i;
304 	char *secnames;
305 
306 	/* Grab section headers and strings so we can tell who is who */
307 	sechdrs = (void *)ehdr + ehdr->e_shoff;
308 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
309 
310 	/* Find the section they want */
311 	for (i = 1; i < ehdr->e_shnum; i++) {
312 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
313 			if (size)
314 				*size = sechdrs[i].sh_size;
315 			return (void *)ehdr + sechdrs[i].sh_offset;
316 		}
317 	}
318 	*size = 0;
319 	return NULL;
320 }
321 
322 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
323 					const char *symname)
324 {
325 	unsigned int i;
326 	char name[MAX_SYMNAME], *c;
327 
328 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
329 		if (lib->dynsym[i].st_name == 0)
330 			continue;
331 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
332 			MAX_SYMNAME);
333 		c = strchr(name, '@');
334 		if (c)
335 			*c = 0;
336 		if (strcmp(symname, name) == 0)
337 			return &lib->dynsym[i];
338 	}
339 	return NULL;
340 }
341 
342 /* Note that we assume the section is .text and the symbol is relative to
343  * the library base
344  */
345 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
346 					    const char *symname)
347 {
348 	Elf32_Sym *sym = find_symbol32(lib, symname);
349 
350 	if (sym == NULL) {
351 		printk(KERN_WARNING "vDSO32: function %s not found !\n",
352 		       symname);
353 		return 0;
354 	}
355 	return sym->st_value - VDSO32_LBASE;
356 }
357 
358 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
359 				       struct lib64_elfinfo *v64,
360 				       const char *orig, const char *fix)
361 {
362 	Elf32_Sym *sym32_gen, *sym32_fix;
363 
364 	sym32_gen = find_symbol32(v32, orig);
365 	if (sym32_gen == NULL) {
366 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
367 		return -1;
368 	}
369 	if (fix == NULL) {
370 		sym32_gen->st_name = 0;
371 		return 0;
372 	}
373 	sym32_fix = find_symbol32(v32, fix);
374 	if (sym32_fix == NULL) {
375 		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
376 		return -1;
377 	}
378 	sym32_gen->st_value = sym32_fix->st_value;
379 	sym32_gen->st_size = sym32_fix->st_size;
380 	sym32_gen->st_info = sym32_fix->st_info;
381 	sym32_gen->st_other = sym32_fix->st_other;
382 	sym32_gen->st_shndx = sym32_fix->st_shndx;
383 
384 	return 0;
385 }
386 
387 
388 #ifdef CONFIG_PPC64
389 
390 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
391 				  unsigned long *size)
392 {
393 	Elf64_Shdr *sechdrs;
394 	unsigned int i;
395 	char *secnames;
396 
397 	/* Grab section headers and strings so we can tell who is who */
398 	sechdrs = (void *)ehdr + ehdr->e_shoff;
399 	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
400 
401 	/* Find the section they want */
402 	for (i = 1; i < ehdr->e_shnum; i++) {
403 		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
404 			if (size)
405 				*size = sechdrs[i].sh_size;
406 			return (void *)ehdr + sechdrs[i].sh_offset;
407 		}
408 	}
409 	if (size)
410 		*size = 0;
411 	return NULL;
412 }
413 
414 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
415 					const char *symname)
416 {
417 	unsigned int i;
418 	char name[MAX_SYMNAME], *c;
419 
420 	for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
421 		if (lib->dynsym[i].st_name == 0)
422 			continue;
423 		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
424 			MAX_SYMNAME);
425 		c = strchr(name, '@');
426 		if (c)
427 			*c = 0;
428 		if (strcmp(symname, name) == 0)
429 			return &lib->dynsym[i];
430 	}
431 	return NULL;
432 }
433 
434 /* Note that we assume the section is .text and the symbol is relative to
435  * the library base
436  */
437 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
438 					    const char *symname)
439 {
440 	Elf64_Sym *sym = find_symbol64(lib, symname);
441 
442 	if (sym == NULL) {
443 		printk(KERN_WARNING "vDSO64: function %s not found !\n",
444 		       symname);
445 		return 0;
446 	}
447 #ifdef VDS64_HAS_DESCRIPTORS
448 	return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
449 		VDSO64_LBASE;
450 #else
451 	return sym->st_value - VDSO64_LBASE;
452 #endif
453 }
454 
455 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
456 				       struct lib64_elfinfo *v64,
457 				       const char *orig, const char *fix)
458 {
459 	Elf64_Sym *sym64_gen, *sym64_fix;
460 
461 	sym64_gen = find_symbol64(v64, orig);
462 	if (sym64_gen == NULL) {
463 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
464 		return -1;
465 	}
466 	if (fix == NULL) {
467 		sym64_gen->st_name = 0;
468 		return 0;
469 	}
470 	sym64_fix = find_symbol64(v64, fix);
471 	if (sym64_fix == NULL) {
472 		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
473 		return -1;
474 	}
475 	sym64_gen->st_value = sym64_fix->st_value;
476 	sym64_gen->st_size = sym64_fix->st_size;
477 	sym64_gen->st_info = sym64_fix->st_info;
478 	sym64_gen->st_other = sym64_fix->st_other;
479 	sym64_gen->st_shndx = sym64_fix->st_shndx;
480 
481 	return 0;
482 }
483 
484 #endif /* CONFIG_PPC64 */
485 
486 
487 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
488 					struct lib64_elfinfo *v64)
489 {
490 	void *sect;
491 
492 	/*
493 	 * Locate symbol tables & text section
494 	 */
495 
496 	v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
497 	v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
498 	if (v32->dynsym == NULL || v32->dynstr == NULL) {
499 		printk(KERN_ERR "vDSO32: required symbol section not found\n");
500 		return -1;
501 	}
502 	sect = find_section32(v32->hdr, ".text", NULL);
503 	if (sect == NULL) {
504 		printk(KERN_ERR "vDSO32: the .text section was not found\n");
505 		return -1;
506 	}
507 	v32->text = sect - vdso32_kbase;
508 
509 #ifdef CONFIG_PPC64
510 	v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
511 	v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
512 	if (v64->dynsym == NULL || v64->dynstr == NULL) {
513 		printk(KERN_ERR "vDSO64: required symbol section not found\n");
514 		return -1;
515 	}
516 	sect = find_section64(v64->hdr, ".text", NULL);
517 	if (sect == NULL) {
518 		printk(KERN_ERR "vDSO64: the .text section was not found\n");
519 		return -1;
520 	}
521 	v64->text = sect - vdso64_kbase;
522 #endif /* CONFIG_PPC64 */
523 
524 	return 0;
525 }
526 
527 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
528 					  struct lib64_elfinfo *v64)
529 {
530 	/*
531 	 * Find signal trampolines
532 	 */
533 
534 #ifdef CONFIG_PPC64
535 	vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
536 #endif
537 	vdso32_sigtramp	   = find_function32(v32, "__kernel_sigtramp32");
538 	vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
539 }
540 
541 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
542 				       struct lib64_elfinfo *v64)
543 {
544 	Elf32_Sym *sym32;
545 #ifdef CONFIG_PPC64
546 	Elf64_Sym *sym64;
547 
548        	sym64 = find_symbol64(v64, "__kernel_datapage_offset");
549 	if (sym64 == NULL) {
550 		printk(KERN_ERR "vDSO64: Can't find symbol "
551 		       "__kernel_datapage_offset !\n");
552 		return -1;
553 	}
554 	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
555 		(vdso64_pages << PAGE_SHIFT) -
556 		(sym64->st_value - VDSO64_LBASE);
557 #endif /* CONFIG_PPC64 */
558 
559 	sym32 = find_symbol32(v32, "__kernel_datapage_offset");
560 	if (sym32 == NULL) {
561 		printk(KERN_ERR "vDSO32: Can't find symbol "
562 		       "__kernel_datapage_offset !\n");
563 		return -1;
564 	}
565 	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
566 		(vdso32_pages << PAGE_SHIFT) -
567 		(sym32->st_value - VDSO32_LBASE);
568 
569 	return 0;
570 }
571 
572 
573 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
574 				      struct lib64_elfinfo *v64)
575 {
576 	void *start32;
577 	unsigned long size32;
578 
579 #ifdef CONFIG_PPC64
580 	void *start64;
581 	unsigned long size64;
582 
583 	start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
584 	if (start64)
585 		do_feature_fixups(cur_cpu_spec->cpu_features,
586 				  start64, start64 + size64);
587 
588 	start64 = find_section64(v64->hdr, "__mmu_ftr_fixup", &size64);
589 	if (start64)
590 		do_feature_fixups(cur_cpu_spec->mmu_features,
591 				  start64, start64 + size64);
592 
593 	start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
594 	if (start64)
595 		do_feature_fixups(powerpc_firmware_features,
596 				  start64, start64 + size64);
597 
598 	start64 = find_section64(v64->hdr, "__lwsync_fixup", &size64);
599 	if (start64)
600 		do_lwsync_fixups(cur_cpu_spec->cpu_features,
601 				 start64, start64 + size64);
602 #endif /* CONFIG_PPC64 */
603 
604 	start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
605 	if (start32)
606 		do_feature_fixups(cur_cpu_spec->cpu_features,
607 				  start32, start32 + size32);
608 
609 	start32 = find_section32(v32->hdr, "__mmu_ftr_fixup", &size32);
610 	if (start32)
611 		do_feature_fixups(cur_cpu_spec->mmu_features,
612 				  start32, start32 + size32);
613 
614 #ifdef CONFIG_PPC64
615 	start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
616 	if (start32)
617 		do_feature_fixups(powerpc_firmware_features,
618 				  start32, start32 + size32);
619 #endif /* CONFIG_PPC64 */
620 
621 	start32 = find_section32(v32->hdr, "__lwsync_fixup", &size32);
622 	if (start32)
623 		do_lwsync_fixups(cur_cpu_spec->cpu_features,
624 				 start32, start32 + size32);
625 
626 	return 0;
627 }
628 
629 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
630 				       struct lib64_elfinfo *v64)
631 {
632 	int i;
633 
634 	for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
635 		struct vdso_patch_def *patch = &vdso_patches[i];
636 		int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
637 			== patch->ftr_value;
638 		if (!match)
639 			continue;
640 
641 		DBG("replacing %s with %s...\n", patch->gen_name,
642 		    patch->fix_name ? "NONE" : patch->fix_name);
643 
644 		/*
645 		 * Patch the 32 bits and 64 bits symbols. Note that we do not
646 		 * patch the "." symbol on 64 bits.
647 		 * It would be easy to do, but doesn't seem to be necessary,
648 		 * patching the OPD symbol is enough.
649 		 */
650 		vdso_do_func_patch32(v32, v64, patch->gen_name,
651 				     patch->fix_name);
652 #ifdef CONFIG_PPC64
653 		vdso_do_func_patch64(v32, v64, patch->gen_name,
654 				     patch->fix_name);
655 #endif /* CONFIG_PPC64 */
656 	}
657 
658 	return 0;
659 }
660 
661 
662 static __init int vdso_setup(void)
663 {
664 	struct lib32_elfinfo	v32;
665 	struct lib64_elfinfo	v64;
666 
667 	v32.hdr = vdso32_kbase;
668 #ifdef CONFIG_PPC64
669 	v64.hdr = vdso64_kbase;
670 #endif
671 	if (vdso_do_find_sections(&v32, &v64))
672 		return -1;
673 
674 	if (vdso_fixup_datapage(&v32, &v64))
675 		return -1;
676 
677 	if (vdso_fixup_features(&v32, &v64))
678 		return -1;
679 
680 	if (vdso_fixup_alt_funcs(&v32, &v64))
681 		return -1;
682 
683 	vdso_setup_trampolines(&v32, &v64);
684 
685 	return 0;
686 }
687 
688 /*
689  * Called from setup_arch to initialize the bitmap of available
690  * syscalls in the systemcfg page
691  */
692 static void __init vdso_setup_syscall_map(void)
693 {
694 	unsigned int i;
695 	extern unsigned long *sys_call_table;
696 	extern unsigned long sys_ni_syscall;
697 
698 
699 	for (i = 0; i < __NR_syscalls; i++) {
700 #ifdef CONFIG_PPC64
701 		if (sys_call_table[i*2] != sys_ni_syscall)
702 			vdso_data->syscall_map_64[i >> 5] |=
703 				0x80000000UL >> (i & 0x1f);
704 		if (sys_call_table[i*2+1] != sys_ni_syscall)
705 			vdso_data->syscall_map_32[i >> 5] |=
706 				0x80000000UL >> (i & 0x1f);
707 #else /* CONFIG_PPC64 */
708 		if (sys_call_table[i] != sys_ni_syscall)
709 			vdso_data->syscall_map_32[i >> 5] |=
710 				0x80000000UL >> (i & 0x1f);
711 #endif /* CONFIG_PPC64 */
712 	}
713 }
714 
715 
716 static int __init vdso_init(void)
717 {
718 	int i;
719 
720 #ifdef CONFIG_PPC64
721 	/*
722 	 * Fill up the "systemcfg" stuff for backward compatibility
723 	 */
724 	strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
725 	vdso_data->version.major = SYSTEMCFG_MAJOR;
726 	vdso_data->version.minor = SYSTEMCFG_MINOR;
727 	vdso_data->processor = mfspr(SPRN_PVR);
728 	/*
729 	 * Fake the old platform number for pSeries and iSeries and add
730 	 * in LPAR bit if necessary
731 	 */
732 	vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
733 	if (firmware_has_feature(FW_FEATURE_LPAR))
734 		vdso_data->platform |= 1;
735 	vdso_data->physicalMemorySize = memblock_phys_mem_size();
736 	vdso_data->dcache_size = ppc64_caches.dsize;
737 	vdso_data->dcache_line_size = ppc64_caches.dline_size;
738 	vdso_data->icache_size = ppc64_caches.isize;
739 	vdso_data->icache_line_size = ppc64_caches.iline_size;
740 
741 	/* XXXOJN: Blocks should be added to ppc64_caches and used instead */
742 	vdso_data->dcache_block_size = ppc64_caches.dline_size;
743 	vdso_data->icache_block_size = ppc64_caches.iline_size;
744 	vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
745 	vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
746 
747 	/*
748 	 * Calculate the size of the 64 bits vDSO
749 	 */
750 	vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
751 	DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
752 #else
753 	vdso_data->dcache_block_size = L1_CACHE_BYTES;
754 	vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
755 	vdso_data->icache_block_size = L1_CACHE_BYTES;
756 	vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
757 #endif /* CONFIG_PPC64 */
758 
759 
760 	/*
761 	 * Calculate the size of the 32 bits vDSO
762 	 */
763 	vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
764 	DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
765 
766 
767 	/*
768 	 * Setup the syscall map in the vDOS
769 	 */
770 	vdso_setup_syscall_map();
771 
772 	/*
773 	 * Initialize the vDSO images in memory, that is do necessary
774 	 * fixups of vDSO symbols, locate trampolines, etc...
775 	 */
776 	if (vdso_setup()) {
777 		printk(KERN_ERR "vDSO setup failure, not enabled !\n");
778 		vdso32_pages = 0;
779 #ifdef CONFIG_PPC64
780 		vdso64_pages = 0;
781 #endif
782 		return 0;
783 	}
784 
785 	/* Make sure pages are in the correct state */
786 	vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
787 				  GFP_KERNEL);
788 	BUG_ON(vdso32_pagelist == NULL);
789 	for (i = 0; i < vdso32_pages; i++) {
790 		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
791 		ClearPageReserved(pg);
792 		get_page(pg);
793 		vdso32_pagelist[i] = pg;
794 	}
795 	vdso32_pagelist[i++] = virt_to_page(vdso_data);
796 	vdso32_pagelist[i] = NULL;
797 
798 #ifdef CONFIG_PPC64
799 	vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
800 				  GFP_KERNEL);
801 	BUG_ON(vdso64_pagelist == NULL);
802 	for (i = 0; i < vdso64_pages; i++) {
803 		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
804 		ClearPageReserved(pg);
805 		get_page(pg);
806 		vdso64_pagelist[i] = pg;
807 	}
808 	vdso64_pagelist[i++] = virt_to_page(vdso_data);
809 	vdso64_pagelist[i] = NULL;
810 #endif /* CONFIG_PPC64 */
811 
812 	get_page(virt_to_page(vdso_data));
813 
814 	smp_wmb();
815 	vdso_ready = 1;
816 
817 	return 0;
818 }
819 arch_initcall(vdso_init);
820 
821 int in_gate_area_no_mm(unsigned long addr)
822 {
823 	return 0;
824 }
825 
826 int in_gate_area(struct mm_struct *mm, unsigned long addr)
827 {
828 	return 0;
829 }
830 
831 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
832 {
833 	return NULL;
834 }
835 
836