[PATCH] powerpc vDSO: use VM_ALWAYSDUMP
[sfrench/cifs-2.6.git] / arch / powerpc / kernel / vdso.c
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/smp_lock.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
26 #include <asm/pgtable.h>
27 #include <asm/system.h>
28 #include <asm/processor.h>
29 #include <asm/mmu.h>
30 #include <asm/mmu_context.h>
31 #include <asm/lmb.h>
32 #include <asm/machdep.h>
33 #include <asm/cputable.h>
34 #include <asm/sections.h>
35 #include <asm/firmware.h>
36 #include <asm/vdso.h>
37 #include <asm/vdso_datapage.h>
38
39 #include "setup.h"
40
41 #undef DEBUG
42
43 #ifdef DEBUG
44 #define DBG(fmt...) printk(fmt)
45 #else
46 #define DBG(fmt...)
47 #endif
48
49 /* Max supported size for symbol names */
50 #define MAX_SYMNAME     64
51
52 extern char vdso32_start, vdso32_end;
53 static void *vdso32_kbase = &vdso32_start;
54 unsigned int vdso32_pages;
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 unsigned int vdso64_pages;
62 unsigned long vdso64_rt_sigtramp;
63 #endif /* CONFIG_PPC64 */
64
65 /*
66  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
67  * Once the early boot kernel code no longer needs to muck around
68  * with it, it will become dynamically allocated
69  */
70 static union {
71         struct vdso_data        data;
72         u8                      page[PAGE_SIZE];
73 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
74 struct vdso_data *vdso_data = &vdso_data_store.data;
75
76 /* Format of the patch table */
77 struct vdso_patch_def
78 {
79         unsigned long   ftr_mask, ftr_value;
80         const char      *gen_name;
81         const char      *fix_name;
82 };
83
84 /* Table of functions to patch based on the CPU type/revision
85  *
86  * Currently, we only change sync_dicache to do nothing on processors
87  * with a coherent icache
88  */
89 static struct vdso_patch_def vdso_patches[] = {
90         {
91                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
92                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
93         },
94         {
95                 CPU_FTR_USE_TB, 0,
96                 "__kernel_gettimeofday", NULL
97         },
98 };
99
100 /*
101  * Some infos carried around for each of them during parsing at
102  * boot time.
103  */
104 struct lib32_elfinfo
105 {
106         Elf32_Ehdr      *hdr;           /* ptr to ELF */
107         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
108         unsigned long   dynsymsize;     /* size of .dynsym section */
109         char            *dynstr;        /* ptr to .dynstr section */
110         unsigned long   text;           /* offset of .text section in .so */
111 };
112
113 struct lib64_elfinfo
114 {
115         Elf64_Ehdr      *hdr;
116         Elf64_Sym       *dynsym;
117         unsigned long   dynsymsize;
118         char            *dynstr;
119         unsigned long   text;
120 };
121
122
123 #ifdef __DEBUG
124 static void dump_one_vdso_page(struct page *pg, struct page *upg)
125 {
126         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
127                page_count(pg),
128                pg->flags);
129         if (upg/* && pg != upg*/) {
130                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
131                                                        << PAGE_SHIFT),
132                        page_count(upg),
133                        upg->flags);
134         }
135         printk("\n");
136 }
137
138 static void dump_vdso_pages(struct vm_area_struct * vma)
139 {
140         int i;
141
142         if (!vma || test_thread_flag(TIF_32BIT)) {
143                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
144                 for (i=0; i<vdso32_pages; i++) {
145                         struct page *pg = virt_to_page(vdso32_kbase +
146                                                        i*PAGE_SIZE);
147                         struct page *upg = (vma && vma->vm_mm) ?
148                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
149                                 : NULL;
150                         dump_one_vdso_page(pg, upg);
151                 }
152         }
153         if (!vma || !test_thread_flag(TIF_32BIT)) {
154                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
155                 for (i=0; i<vdso64_pages; i++) {
156                         struct page *pg = virt_to_page(vdso64_kbase +
157                                                        i*PAGE_SIZE);
158                         struct page *upg = (vma && vma->vm_mm) ?
159                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
160                                 : NULL;
161                         dump_one_vdso_page(pg, upg);
162                 }
163         }
164 }
165 #endif /* DEBUG */
166
167 /*
168  * Keep a dummy vma_close for now, it will prevent VMA merging.
169  */
170 static void vdso_vma_close(struct vm_area_struct * vma)
171 {
172 }
173
174 /*
175  * Our nopage() function, maps in the actual vDSO kernel pages, they will
176  * be mapped read-only by do_no_page(), and eventually COW'ed, either
177  * right away for an initial write access, or by do_wp_page().
178  */
179 static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
180                                      unsigned long address, int *type)
181 {
182         unsigned long offset = address - vma->vm_start;
183         struct page *pg;
184 #ifdef CONFIG_PPC64
185         void *vbase = (vma->vm_mm->task_size > TASK_SIZE_USER32) ?
186                 vdso64_kbase : vdso32_kbase;
187 #else
188         void *vbase = vdso32_kbase;
189 #endif
190
191         DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
192             current->comm, address, offset);
193
194         if (address < vma->vm_start || address > vma->vm_end)
195                 return NOPAGE_SIGBUS;
196
197         /*
198          * Last page is systemcfg.
199          */
200         if ((vma->vm_end - address) <= PAGE_SIZE)
201                 pg = virt_to_page(vdso_data);
202         else
203                 pg = virt_to_page(vbase + offset);
204
205         get_page(pg);
206         DBG(" ->page count: %d\n", page_count(pg));
207
208         return pg;
209 }
210
211 static struct vm_operations_struct vdso_vmops = {
212         .close  = vdso_vma_close,
213         .nopage = vdso_vma_nopage,
214 };
215
216 /*
217  * This is called from binfmt_elf, we create the special vma for the
218  * vDSO and insert it into the mm struct tree
219  */
220 int arch_setup_additional_pages(struct linux_binprm *bprm,
221                                 int executable_stack)
222 {
223         struct mm_struct *mm = current->mm;
224         struct vm_area_struct *vma;
225         unsigned long vdso_pages;
226         unsigned long vdso_base;
227         int rc;
228
229 #ifdef CONFIG_PPC64
230         if (test_thread_flag(TIF_32BIT)) {
231                 vdso_pages = vdso32_pages;
232                 vdso_base = VDSO32_MBASE;
233         } else {
234                 vdso_pages = vdso64_pages;
235                 vdso_base = VDSO64_MBASE;
236         }
237 #else
238         vdso_pages = vdso32_pages;
239         vdso_base = VDSO32_MBASE;
240 #endif
241
242         current->mm->context.vdso_base = 0;
243
244         /* vDSO has a problem and was disabled, just don't "enable" it for the
245          * process
246          */
247         if (vdso_pages == 0)
248                 return 0;
249         /* Add a page to the vdso size for the data page */
250         vdso_pages ++;
251
252         /*
253          * pick a base address for the vDSO in process space. We try to put it
254          * at vdso_base which is the "natural" base for it, but we might fail
255          * and end up putting it elsewhere.
256          */
257         down_write(&mm->mmap_sem);
258         vdso_base = get_unmapped_area(NULL, vdso_base,
259                                       vdso_pages << PAGE_SHIFT, 0, 0);
260         if (IS_ERR_VALUE(vdso_base)) {
261                 rc = vdso_base;
262                 goto fail_mmapsem;
263         }
264
265
266         /* Allocate a VMA structure and fill it up */
267         vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
268         if (vma == NULL) {
269                 rc = -ENOMEM;
270                 goto fail_mmapsem;
271         }
272         vma->vm_mm = mm;
273         vma->vm_start = vdso_base;
274         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
275
276         /*
277          * our vma flags don't have VM_WRITE so by default, the process isn't
278          * allowed to write those pages.
279          * gdb can break that with ptrace interface, and thus trigger COW on
280          * those pages but it's then your responsibility to never do that on
281          * the "data" page of the vDSO or you'll stop getting kernel updates
282          * and your nice userland gettimeofday will be totally dead.
283          * It's fine to use that for setting breakpoints in the vDSO code
284          * pages though
285          */
286         vma->vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
287         /*
288          * Make sure the vDSO gets into every core dump.
289          * Dumping its contents makes post-mortem fully interpretable later
290          * without matching up the same kernel and hardware config to see
291          * what PC values meant.
292          */
293         vma->vm_flags |= VM_ALWAYSDUMP;
294         vma->vm_flags |= mm->def_flags;
295         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
296         vma->vm_ops = &vdso_vmops;
297
298         /* Insert new VMA */
299         rc = insert_vm_struct(mm, vma);
300         if (rc)
301                 goto fail_vma;
302
303         /* Put vDSO base into mm struct and account for memory usage */
304         current->mm->context.vdso_base = vdso_base;
305         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
306         up_write(&mm->mmap_sem);
307         return 0;
308
309  fail_vma:
310         kmem_cache_free(vm_area_cachep, vma);
311  fail_mmapsem:
312         up_write(&mm->mmap_sem);
313         return rc;
314 }
315
316 const char *arch_vma_name(struct vm_area_struct *vma)
317 {
318         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
319                 return "[vdso]";
320         return NULL;
321 }
322
323
324
325 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
326                                   unsigned long *size)
327 {
328         Elf32_Shdr *sechdrs;
329         unsigned int i;
330         char *secnames;
331
332         /* Grab section headers and strings so we can tell who is who */
333         sechdrs = (void *)ehdr + ehdr->e_shoff;
334         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
335
336         /* Find the section they want */
337         for (i = 1; i < ehdr->e_shnum; i++) {
338                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
339                         if (size)
340                                 *size = sechdrs[i].sh_size;
341                         return (void *)ehdr + sechdrs[i].sh_offset;
342                 }
343         }
344         *size = 0;
345         return NULL;
346 }
347
348 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
349                                         const char *symname)
350 {
351         unsigned int i;
352         char name[MAX_SYMNAME], *c;
353
354         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
355                 if (lib->dynsym[i].st_name == 0)
356                         continue;
357                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
358                         MAX_SYMNAME);
359                 c = strchr(name, '@');
360                 if (c)
361                         *c = 0;
362                 if (strcmp(symname, name) == 0)
363                         return &lib->dynsym[i];
364         }
365         return NULL;
366 }
367
368 /* Note that we assume the section is .text and the symbol is relative to
369  * the library base
370  */
371 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
372                                             const char *symname)
373 {
374         Elf32_Sym *sym = find_symbol32(lib, symname);
375
376         if (sym == NULL) {
377                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
378                        symname);
379                 return 0;
380         }
381         return sym->st_value - VDSO32_LBASE;
382 }
383
384 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
385                                 struct lib64_elfinfo *v64,
386                                 const char *orig, const char *fix)
387 {
388         Elf32_Sym *sym32_gen, *sym32_fix;
389
390         sym32_gen = find_symbol32(v32, orig);
391         if (sym32_gen == NULL) {
392                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
393                 return -1;
394         }
395         if (fix == NULL) {
396                 sym32_gen->st_name = 0;
397                 return 0;
398         }
399         sym32_fix = find_symbol32(v32, fix);
400         if (sym32_fix == NULL) {
401                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
402                 return -1;
403         }
404         sym32_gen->st_value = sym32_fix->st_value;
405         sym32_gen->st_size = sym32_fix->st_size;
406         sym32_gen->st_info = sym32_fix->st_info;
407         sym32_gen->st_other = sym32_fix->st_other;
408         sym32_gen->st_shndx = sym32_fix->st_shndx;
409
410         return 0;
411 }
412
413
414 #ifdef CONFIG_PPC64
415
416 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
417                                   unsigned long *size)
418 {
419         Elf64_Shdr *sechdrs;
420         unsigned int i;
421         char *secnames;
422
423         /* Grab section headers and strings so we can tell who is who */
424         sechdrs = (void *)ehdr + ehdr->e_shoff;
425         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
426
427         /* Find the section they want */
428         for (i = 1; i < ehdr->e_shnum; i++) {
429                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
430                         if (size)
431                                 *size = sechdrs[i].sh_size;
432                         return (void *)ehdr + sechdrs[i].sh_offset;
433                 }
434         }
435         if (size)
436                 *size = 0;
437         return NULL;
438 }
439
440 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
441                                         const char *symname)
442 {
443         unsigned int i;
444         char name[MAX_SYMNAME], *c;
445
446         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
447                 if (lib->dynsym[i].st_name == 0)
448                         continue;
449                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
450                         MAX_SYMNAME);
451                 c = strchr(name, '@');
452                 if (c)
453                         *c = 0;
454                 if (strcmp(symname, name) == 0)
455                         return &lib->dynsym[i];
456         }
457         return NULL;
458 }
459
460 /* Note that we assume the section is .text and the symbol is relative to
461  * the library base
462  */
463 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
464                                             const char *symname)
465 {
466         Elf64_Sym *sym = find_symbol64(lib, symname);
467
468         if (sym == NULL) {
469                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
470                        symname);
471                 return 0;
472         }
473 #ifdef VDS64_HAS_DESCRIPTORS
474         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
475                 VDSO64_LBASE;
476 #else
477         return sym->st_value - VDSO64_LBASE;
478 #endif
479 }
480
481 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
482                                 struct lib64_elfinfo *v64,
483                                 const char *orig, const char *fix)
484 {
485         Elf64_Sym *sym64_gen, *sym64_fix;
486
487         sym64_gen = find_symbol64(v64, orig);
488         if (sym64_gen == NULL) {
489                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
490                 return -1;
491         }
492         if (fix == NULL) {
493                 sym64_gen->st_name = 0;
494                 return 0;
495         }
496         sym64_fix = find_symbol64(v64, fix);
497         if (sym64_fix == NULL) {
498                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
499                 return -1;
500         }
501         sym64_gen->st_value = sym64_fix->st_value;
502         sym64_gen->st_size = sym64_fix->st_size;
503         sym64_gen->st_info = sym64_fix->st_info;
504         sym64_gen->st_other = sym64_fix->st_other;
505         sym64_gen->st_shndx = sym64_fix->st_shndx;
506
507         return 0;
508 }
509
510 #endif /* CONFIG_PPC64 */
511
512
513 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
514                                         struct lib64_elfinfo *v64)
515 {
516         void *sect;
517
518         /*
519          * Locate symbol tables & text section
520          */
521
522         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
523         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
524         if (v32->dynsym == NULL || v32->dynstr == NULL) {
525                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
526                 return -1;
527         }
528         sect = find_section32(v32->hdr, ".text", NULL);
529         if (sect == NULL) {
530                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
531                 return -1;
532         }
533         v32->text = sect - vdso32_kbase;
534
535 #ifdef CONFIG_PPC64
536         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
537         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
538         if (v64->dynsym == NULL || v64->dynstr == NULL) {
539                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
540                 return -1;
541         }
542         sect = find_section64(v64->hdr, ".text", NULL);
543         if (sect == NULL) {
544                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
545                 return -1;
546         }
547         v64->text = sect - vdso64_kbase;
548 #endif /* CONFIG_PPC64 */
549
550         return 0;
551 }
552
553 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
554                                           struct lib64_elfinfo *v64)
555 {
556         /*
557          * Find signal trampolines
558          */
559
560 #ifdef CONFIG_PPC64
561         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
562 #endif
563         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
564         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
565 }
566
567 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
568                                        struct lib64_elfinfo *v64)
569 {
570         Elf32_Sym *sym32;
571 #ifdef CONFIG_PPC64
572         Elf64_Sym *sym64;
573
574         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
575         if (sym64 == NULL) {
576                 printk(KERN_ERR "vDSO64: Can't find symbol "
577                        "__kernel_datapage_offset !\n");
578                 return -1;
579         }
580         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
581                 (vdso64_pages << PAGE_SHIFT) -
582                 (sym64->st_value - VDSO64_LBASE);
583 #endif /* CONFIG_PPC64 */
584
585         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
586         if (sym32 == NULL) {
587                 printk(KERN_ERR "vDSO32: Can't find symbol "
588                        "__kernel_datapage_offset !\n");
589                 return -1;
590         }
591         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
592                 (vdso32_pages << PAGE_SHIFT) -
593                 (sym32->st_value - VDSO32_LBASE);
594
595         return 0;
596 }
597
598
599 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
600                                       struct lib64_elfinfo *v64)
601 {
602         void *start32;
603         unsigned long size32;
604
605 #ifdef CONFIG_PPC64
606         void *start64;
607         unsigned long size64;
608
609         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
610         if (start64)
611                 do_feature_fixups(cur_cpu_spec->cpu_features,
612                                   start64, start64 + size64);
613
614         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
615         if (start64)
616                 do_feature_fixups(powerpc_firmware_features,
617                                   start64, start64 + size64);
618 #endif /* CONFIG_PPC64 */
619
620         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
621         if (start32)
622                 do_feature_fixups(cur_cpu_spec->cpu_features,
623                                   start32, start32 + size32);
624
625 #ifdef CONFIG_PPC64
626         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
627         if (start32)
628                 do_feature_fixups(powerpc_firmware_features,
629                                   start32, start32 + size32);
630 #endif /* CONFIG_PPC64 */
631
632         return 0;
633 }
634
635 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
636                                        struct lib64_elfinfo *v64)
637 {
638         int i;
639
640         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
641                 struct vdso_patch_def *patch = &vdso_patches[i];
642                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
643                         == patch->ftr_value;
644                 if (!match)
645                         continue;
646
647                 DBG("replacing %s with %s...\n", patch->gen_name,
648                     patch->fix_name ? "NONE" : patch->fix_name);
649
650                 /*
651                  * Patch the 32 bits and 64 bits symbols. Note that we do not
652                  * patch the "." symbol on 64 bits.
653                  * It would be easy to do, but doesn't seem to be necessary,
654                  * patching the OPD symbol is enough.
655                  */
656                 vdso_do_func_patch32(v32, v64, patch->gen_name,
657                                      patch->fix_name);
658 #ifdef CONFIG_PPC64
659                 vdso_do_func_patch64(v32, v64, patch->gen_name,
660                                      patch->fix_name);
661 #endif /* CONFIG_PPC64 */
662         }
663
664         return 0;
665 }
666
667
668 static __init int vdso_setup(void)
669 {
670         struct lib32_elfinfo    v32;
671         struct lib64_elfinfo    v64;
672
673         v32.hdr = vdso32_kbase;
674 #ifdef CONFIG_PPC64
675         v64.hdr = vdso64_kbase;
676 #endif
677         if (vdso_do_find_sections(&v32, &v64))
678                 return -1;
679
680         if (vdso_fixup_datapage(&v32, &v64))
681                 return -1;
682
683         if (vdso_fixup_features(&v32, &v64))
684                 return -1;
685
686         if (vdso_fixup_alt_funcs(&v32, &v64))
687                 return -1;
688
689         vdso_setup_trampolines(&v32, &v64);
690
691         return 0;
692 }
693
694 /*
695  * Called from setup_arch to initialize the bitmap of available
696  * syscalls in the systemcfg page
697  */
698 static void __init vdso_setup_syscall_map(void)
699 {
700         unsigned int i;
701         extern unsigned long *sys_call_table;
702         extern unsigned long sys_ni_syscall;
703
704
705         for (i = 0; i < __NR_syscalls; i++) {
706 #ifdef CONFIG_PPC64
707                 if (sys_call_table[i*2] != sys_ni_syscall)
708                         vdso_data->syscall_map_64[i >> 5] |=
709                                 0x80000000UL >> (i & 0x1f);
710                 if (sys_call_table[i*2+1] != sys_ni_syscall)
711                         vdso_data->syscall_map_32[i >> 5] |=
712                                 0x80000000UL >> (i & 0x1f);
713 #else /* CONFIG_PPC64 */
714                 if (sys_call_table[i] != sys_ni_syscall)
715                         vdso_data->syscall_map_32[i >> 5] |=
716                                 0x80000000UL >> (i & 0x1f);
717 #endif /* CONFIG_PPC64 */
718         }
719 }
720
721
722 void __init vdso_init(void)
723 {
724         int i;
725
726 #ifdef CONFIG_PPC64
727         /*
728          * Fill up the "systemcfg" stuff for backward compatiblity
729          */
730         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
731         vdso_data->version.major = SYSTEMCFG_MAJOR;
732         vdso_data->version.minor = SYSTEMCFG_MINOR;
733         vdso_data->processor = mfspr(SPRN_PVR);
734         /*
735          * Fake the old platform number for pSeries and iSeries and add
736          * in LPAR bit if necessary
737          */
738         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
739         if (firmware_has_feature(FW_FEATURE_LPAR))
740                 vdso_data->platform |= 1;
741         vdso_data->physicalMemorySize = lmb_phys_mem_size();
742         vdso_data->dcache_size = ppc64_caches.dsize;
743         vdso_data->dcache_line_size = ppc64_caches.dline_size;
744         vdso_data->icache_size = ppc64_caches.isize;
745         vdso_data->icache_line_size = ppc64_caches.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 #endif /* CONFIG_PPC64 */
753
754
755         /*
756          * Calculate the size of the 32 bits vDSO
757          */
758         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
759         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
760
761
762         /*
763          * Setup the syscall map in the vDOS
764          */
765         vdso_setup_syscall_map();
766
767         /*
768          * Initialize the vDSO images in memory, that is do necessary
769          * fixups of vDSO symbols, locate trampolines, etc...
770          */
771         if (vdso_setup()) {
772                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
773                 vdso32_pages = 0;
774 #ifdef CONFIG_PPC64
775                 vdso64_pages = 0;
776 #endif
777                 return;
778         }
779
780         /* Make sure pages are in the correct state */
781         for (i = 0; i < vdso32_pages; i++) {
782                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
783                 ClearPageReserved(pg);
784                 get_page(pg);
785
786         }
787 #ifdef CONFIG_PPC64
788         for (i = 0; i < vdso64_pages; i++) {
789                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
790                 ClearPageReserved(pg);
791                 get_page(pg);
792         }
793 #endif /* CONFIG_PPC64 */
794
795         get_page(virt_to_page(vdso_data));
796 }
797
798 int in_gate_area_no_task(unsigned long addr)
799 {
800         return 0;
801 }
802
803 int in_gate_area(struct task_struct *task, unsigned long addr)
804 {
805         return 0;
806 }
807
808 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
809 {
810         return NULL;
811 }
812