Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm...
[linux-2.6.git] / arch / powerpc / kernel / vdso.c
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         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
268                                      VM_READ|VM_EXEC|
269                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
270                                      vdso_pagelist);
271         if (rc) {
272                 current->mm->context.vdso_base = 0;
273                 goto fail_mmapsem;
274         }
275
276         up_write(&mm->mmap_sem);
277         return 0;
278
279  fail_mmapsem:
280         up_write(&mm->mmap_sem);
281         return rc;
282 }
283
284 const char *arch_vma_name(struct vm_area_struct *vma)
285 {
286         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
287                 return "[vdso]";
288         return NULL;
289 }
290
291
292
293 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
294                                   unsigned long *size)
295 {
296         Elf32_Shdr *sechdrs;
297         unsigned int i;
298         char *secnames;
299
300         /* Grab section headers and strings so we can tell who is who */
301         sechdrs = (void *)ehdr + ehdr->e_shoff;
302         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
303
304         /* Find the section they want */
305         for (i = 1; i < ehdr->e_shnum; i++) {
306                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
307                         if (size)
308                                 *size = sechdrs[i].sh_size;
309                         return (void *)ehdr + sechdrs[i].sh_offset;
310                 }
311         }
312         *size = 0;
313         return NULL;
314 }
315
316 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
317                                         const char *symname)
318 {
319         unsigned int i;
320         char name[MAX_SYMNAME], *c;
321
322         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
323                 if (lib->dynsym[i].st_name == 0)
324                         continue;
325                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
326                         MAX_SYMNAME);
327                 c = strchr(name, '@');
328                 if (c)
329                         *c = 0;
330                 if (strcmp(symname, name) == 0)
331                         return &lib->dynsym[i];
332         }
333         return NULL;
334 }
335
336 /* Note that we assume the section is .text and the symbol is relative to
337  * the library base
338  */
339 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
340                                             const char *symname)
341 {
342         Elf32_Sym *sym = find_symbol32(lib, symname);
343
344         if (sym == NULL) {
345                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
346                        symname);
347                 return 0;
348         }
349         return sym->st_value - VDSO32_LBASE;
350 }
351
352 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
353                                        struct lib64_elfinfo *v64,
354                                        const char *orig, const char *fix)
355 {
356         Elf32_Sym *sym32_gen, *sym32_fix;
357
358         sym32_gen = find_symbol32(v32, orig);
359         if (sym32_gen == NULL) {
360                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
361                 return -1;
362         }
363         if (fix == NULL) {
364                 sym32_gen->st_name = 0;
365                 return 0;
366         }
367         sym32_fix = find_symbol32(v32, fix);
368         if (sym32_fix == NULL) {
369                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
370                 return -1;
371         }
372         sym32_gen->st_value = sym32_fix->st_value;
373         sym32_gen->st_size = sym32_fix->st_size;
374         sym32_gen->st_info = sym32_fix->st_info;
375         sym32_gen->st_other = sym32_fix->st_other;
376         sym32_gen->st_shndx = sym32_fix->st_shndx;
377
378         return 0;
379 }
380
381
382 #ifdef CONFIG_PPC64
383
384 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
385                                   unsigned long *size)
386 {
387         Elf64_Shdr *sechdrs;
388         unsigned int i;
389         char *secnames;
390
391         /* Grab section headers and strings so we can tell who is who */
392         sechdrs = (void *)ehdr + ehdr->e_shoff;
393         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
394
395         /* Find the section they want */
396         for (i = 1; i < ehdr->e_shnum; i++) {
397                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
398                         if (size)
399                                 *size = sechdrs[i].sh_size;
400                         return (void *)ehdr + sechdrs[i].sh_offset;
401                 }
402         }
403         if (size)
404                 *size = 0;
405         return NULL;
406 }
407
408 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
409                                         const char *symname)
410 {
411         unsigned int i;
412         char name[MAX_SYMNAME], *c;
413
414         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
415                 if (lib->dynsym[i].st_name == 0)
416                         continue;
417                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
418                         MAX_SYMNAME);
419                 c = strchr(name, '@');
420                 if (c)
421                         *c = 0;
422                 if (strcmp(symname, name) == 0)
423                         return &lib->dynsym[i];
424         }
425         return NULL;
426 }
427
428 /* Note that we assume the section is .text and the symbol is relative to
429  * the library base
430  */
431 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
432                                             const char *symname)
433 {
434         Elf64_Sym *sym = find_symbol64(lib, symname);
435
436         if (sym == NULL) {
437                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
438                        symname);
439                 return 0;
440         }
441 #ifdef VDS64_HAS_DESCRIPTORS
442         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
443                 VDSO64_LBASE;
444 #else
445         return sym->st_value - VDSO64_LBASE;
446 #endif
447 }
448
449 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
450                                        struct lib64_elfinfo *v64,
451                                        const char *orig, const char *fix)
452 {
453         Elf64_Sym *sym64_gen, *sym64_fix;
454
455         sym64_gen = find_symbol64(v64, orig);
456         if (sym64_gen == NULL) {
457                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
458                 return -1;
459         }
460         if (fix == NULL) {
461                 sym64_gen->st_name = 0;
462                 return 0;
463         }
464         sym64_fix = find_symbol64(v64, fix);
465         if (sym64_fix == NULL) {
466                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
467                 return -1;
468         }
469         sym64_gen->st_value = sym64_fix->st_value;
470         sym64_gen->st_size = sym64_fix->st_size;
471         sym64_gen->st_info = sym64_fix->st_info;
472         sym64_gen->st_other = sym64_fix->st_other;
473         sym64_gen->st_shndx = sym64_fix->st_shndx;
474
475         return 0;
476 }
477
478 #endif /* CONFIG_PPC64 */
479
480
481 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
482                                         struct lib64_elfinfo *v64)
483 {
484         void *sect;
485
486         /*
487          * Locate symbol tables & text section
488          */
489
490         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
491         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
492         if (v32->dynsym == NULL || v32->dynstr == NULL) {
493                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
494                 return -1;
495         }
496         sect = find_section32(v32->hdr, ".text", NULL);
497         if (sect == NULL) {
498                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
499                 return -1;
500         }
501         v32->text = sect - vdso32_kbase;
502
503 #ifdef CONFIG_PPC64
504         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
505         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
506         if (v64->dynsym == NULL || v64->dynstr == NULL) {
507                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
508                 return -1;
509         }
510         sect = find_section64(v64->hdr, ".text", NULL);
511         if (sect == NULL) {
512                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
513                 return -1;
514         }
515         v64->text = sect - vdso64_kbase;
516 #endif /* CONFIG_PPC64 */
517
518         return 0;
519 }
520
521 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
522                                           struct lib64_elfinfo *v64)
523 {
524         /*
525          * Find signal trampolines
526          */
527
528 #ifdef CONFIG_PPC64
529         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
530 #endif
531         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
532         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
533 }
534
535 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
536                                        struct lib64_elfinfo *v64)
537 {
538         Elf32_Sym *sym32;
539 #ifdef CONFIG_PPC64
540         Elf64_Sym *sym64;
541
542         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
543         if (sym64 == NULL) {
544                 printk(KERN_ERR "vDSO64: Can't find symbol "
545                        "__kernel_datapage_offset !\n");
546                 return -1;
547         }
548         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
549                 (vdso64_pages << PAGE_SHIFT) -
550                 (sym64->st_value - VDSO64_LBASE);
551 #endif /* CONFIG_PPC64 */
552
553         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
554         if (sym32 == NULL) {
555                 printk(KERN_ERR "vDSO32: Can't find symbol "
556                        "__kernel_datapage_offset !\n");
557                 return -1;
558         }
559         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
560                 (vdso32_pages << PAGE_SHIFT) -
561                 (sym32->st_value - VDSO32_LBASE);
562
563         return 0;
564 }
565
566
567 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
568                                       struct lib64_elfinfo *v64)
569 {
570         void *start32;
571         unsigned long size32;
572
573 #ifdef CONFIG_PPC64
574         void *start64;
575         unsigned long size64;
576
577         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
578         if (start64)
579                 do_feature_fixups(cur_cpu_spec->cpu_features,
580                                   start64, start64 + size64);
581
582         start64 = find_section64(v64->hdr, "__mmu_ftr_fixup", &size64);
583         if (start64)
584                 do_feature_fixups(cur_cpu_spec->mmu_features,
585                                   start64, start64 + size64);
586
587         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
588         if (start64)
589                 do_feature_fixups(powerpc_firmware_features,
590                                   start64, start64 + size64);
591
592         start64 = find_section64(v64->hdr, "__lwsync_fixup", &size64);
593         if (start64)
594                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
595                                  start64, start64 + size64);
596 #endif /* CONFIG_PPC64 */
597
598         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
599         if (start32)
600                 do_feature_fixups(cur_cpu_spec->cpu_features,
601                                   start32, start32 + size32);
602
603         start32 = find_section32(v32->hdr, "__mmu_ftr_fixup", &size32);
604         if (start32)
605                 do_feature_fixups(cur_cpu_spec->mmu_features,
606                                   start32, start32 + size32);
607
608 #ifdef CONFIG_PPC64
609         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
610         if (start32)
611                 do_feature_fixups(powerpc_firmware_features,
612                                   start32, start32 + size32);
613 #endif /* CONFIG_PPC64 */
614
615         start32 = find_section32(v32->hdr, "__lwsync_fixup", &size32);
616         if (start32)
617                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
618                                  start32, start32 + size32);
619
620         return 0;
621 }
622
623 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
624                                        struct lib64_elfinfo *v64)
625 {
626         int i;
627
628         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
629                 struct vdso_patch_def *patch = &vdso_patches[i];
630                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
631                         == patch->ftr_value;
632                 if (!match)
633                         continue;
634
635                 DBG("replacing %s with %s...\n", patch->gen_name,
636                     patch->fix_name ? "NONE" : patch->fix_name);
637
638                 /*
639                  * Patch the 32 bits and 64 bits symbols. Note that we do not
640                  * patch the "." symbol on 64 bits.
641                  * It would be easy to do, but doesn't seem to be necessary,
642                  * patching the OPD symbol is enough.
643                  */
644                 vdso_do_func_patch32(v32, v64, patch->gen_name,
645                                      patch->fix_name);
646 #ifdef CONFIG_PPC64
647                 vdso_do_func_patch64(v32, v64, patch->gen_name,
648                                      patch->fix_name);
649 #endif /* CONFIG_PPC64 */
650         }
651
652         return 0;
653 }
654
655
656 static __init int vdso_setup(void)
657 {
658         struct lib32_elfinfo    v32;
659         struct lib64_elfinfo    v64;
660
661         v32.hdr = vdso32_kbase;
662 #ifdef CONFIG_PPC64
663         v64.hdr = vdso64_kbase;
664 #endif
665         if (vdso_do_find_sections(&v32, &v64))
666                 return -1;
667
668         if (vdso_fixup_datapage(&v32, &v64))
669                 return -1;
670
671         if (vdso_fixup_features(&v32, &v64))
672                 return -1;
673
674         if (vdso_fixup_alt_funcs(&v32, &v64))
675                 return -1;
676
677         vdso_setup_trampolines(&v32, &v64);
678
679         return 0;
680 }
681
682 /*
683  * Called from setup_arch to initialize the bitmap of available
684  * syscalls in the systemcfg page
685  */
686 static void __init vdso_setup_syscall_map(void)
687 {
688         unsigned int i;
689         extern unsigned long *sys_call_table;
690         extern unsigned long sys_ni_syscall;
691
692
693         for (i = 0; i < __NR_syscalls; i++) {
694 #ifdef CONFIG_PPC64
695                 if (sys_call_table[i*2] != sys_ni_syscall)
696                         vdso_data->syscall_map_64[i >> 5] |=
697                                 0x80000000UL >> (i & 0x1f);
698                 if (sys_call_table[i*2+1] != sys_ni_syscall)
699                         vdso_data->syscall_map_32[i >> 5] |=
700                                 0x80000000UL >> (i & 0x1f);
701 #else /* CONFIG_PPC64 */
702                 if (sys_call_table[i] != sys_ni_syscall)
703                         vdso_data->syscall_map_32[i >> 5] |=
704                                 0x80000000UL >> (i & 0x1f);
705 #endif /* CONFIG_PPC64 */
706         }
707 }
708
709
710 static int __init vdso_init(void)
711 {
712         int i;
713
714 #ifdef CONFIG_PPC64
715         /*
716          * Fill up the "systemcfg" stuff for backward compatibility
717          */
718         strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
719         vdso_data->version.major = SYSTEMCFG_MAJOR;
720         vdso_data->version.minor = SYSTEMCFG_MINOR;
721         vdso_data->processor = mfspr(SPRN_PVR);
722         /*
723          * Fake the old platform number for pSeries and add
724          * in LPAR bit if necessary
725          */
726         vdso_data->platform = 0x100;
727         if (firmware_has_feature(FW_FEATURE_LPAR))
728                 vdso_data->platform |= 1;
729         vdso_data->physicalMemorySize = memblock_phys_mem_size();
730         vdso_data->dcache_size = ppc64_caches.dsize;
731         vdso_data->dcache_line_size = ppc64_caches.dline_size;
732         vdso_data->icache_size = ppc64_caches.isize;
733         vdso_data->icache_line_size = ppc64_caches.iline_size;
734
735         /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
736         vdso_data->dcache_block_size = ppc64_caches.dline_size;
737         vdso_data->icache_block_size = ppc64_caches.iline_size;
738         vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
739         vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
740
741         /*
742          * Calculate the size of the 64 bits vDSO
743          */
744         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
745         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
746 #else
747         vdso_data->dcache_block_size = L1_CACHE_BYTES;
748         vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
749         vdso_data->icache_block_size = L1_CACHE_BYTES;
750         vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
751 #endif /* CONFIG_PPC64 */
752
753
754         /*
755          * Calculate the size of the 32 bits vDSO
756          */
757         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
758         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
759
760
761         /*
762          * Setup the syscall map in the vDOS
763          */
764         vdso_setup_syscall_map();
765
766         /*
767          * Initialize the vDSO images in memory, that is do necessary
768          * fixups of vDSO symbols, locate trampolines, etc...
769          */
770         if (vdso_setup()) {
771                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
772                 vdso32_pages = 0;
773 #ifdef CONFIG_PPC64
774                 vdso64_pages = 0;
775 #endif
776                 return 0;
777         }
778
779         /* Make sure pages are in the correct state */
780         vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
781                                   GFP_KERNEL);
782         BUG_ON(vdso32_pagelist == NULL);
783         for (i = 0; i < vdso32_pages; i++) {
784                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
785                 ClearPageReserved(pg);
786                 get_page(pg);
787                 vdso32_pagelist[i] = pg;
788         }
789         vdso32_pagelist[i++] = virt_to_page(vdso_data);
790         vdso32_pagelist[i] = NULL;
791
792 #ifdef CONFIG_PPC64
793         vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
794                                   GFP_KERNEL);
795         BUG_ON(vdso64_pagelist == NULL);
796         for (i = 0; i < vdso64_pages; i++) {
797                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
798                 ClearPageReserved(pg);
799                 get_page(pg);
800                 vdso64_pagelist[i] = pg;
801         }
802         vdso64_pagelist[i++] = virt_to_page(vdso_data);
803         vdso64_pagelist[i] = NULL;
804 #endif /* CONFIG_PPC64 */
805
806         get_page(virt_to_page(vdso_data));
807
808         smp_wmb();
809         vdso_ready = 1;
810
811         return 0;
812 }
813 arch_initcall(vdso_init);
814
815 int in_gate_area_no_mm(unsigned long addr)
816 {
817         return 0;
818 }
819
820 int in_gate_area(struct mm_struct *mm, unsigned long addr)
821 {
822         return 0;
823 }
824
825 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
826 {
827         return NULL;
828 }
829