[PATCH] powerpc: Merge vdso's and add vdso support to 32 bits kernel
[linux-2.6.git] / arch / powerpc / kernel / vdso.c
1 /*
2  *  linux/arch/ppc64/kernel/vdso.c
3  *
4  *    Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
5  *                       <benh@kernel.crashing.org>
6  *
7  *  This program is free software; you can redistribute it and/or
8  *  modify it under the terms of the GNU General Public License
9  *  as published by the Free Software Foundation; either version
10  *  2 of the License, or (at your option) any later version.
11  */
12
13 #include <linux/config.h>
14 #include <linux/module.h>
15 #include <linux/errno.h>
16 #include <linux/sched.h>
17 #include <linux/kernel.h>
18 #include <linux/mm.h>
19 #include <linux/smp.h>
20 #include <linux/smp_lock.h>
21 #include <linux/stddef.h>
22 #include <linux/unistd.h>
23 #include <linux/slab.h>
24 #include <linux/user.h>
25 #include <linux/elf.h>
26 #include <linux/security.h>
27 #include <linux/bootmem.h>
28
29 #include <asm/pgtable.h>
30 #include <asm/system.h>
31 #include <asm/processor.h>
32 #include <asm/mmu.h>
33 #include <asm/mmu_context.h>
34 #include <asm/lmb.h>
35 #include <asm/machdep.h>
36 #include <asm/cputable.h>
37 #include <asm/sections.h>
38 #include <asm/vdso.h>
39 #include <asm/vdso_datapage.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->vm_mm, vma->vm_start +
149                                             i*PAGE_SIZE, 0)
150                                 : NULL;
151                         dump_one_vdso_page(pg, upg);
152                 }
153         }
154         if (!vma || !test_thread_flag(TIF_32BIT)) {
155                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
156                 for (i=0; i<vdso64_pages; i++) {
157                         struct page *pg = virt_to_page(vdso64_kbase +
158                                                        i*PAGE_SIZE);
159                         struct page *upg = (vma && vma->vm_mm) ?
160                                 follow_page(vma->vm_mm, vma->vm_start +
161                                             i*PAGE_SIZE, 0)
162                                 : NULL;
163                         dump_one_vdso_page(pg, upg);
164                 }
165         }
166 }
167 #endif /* DEBUG */
168
169 /*
170  * Keep a dummy vma_close for now, it will prevent VMA merging.
171  */
172 static void vdso_vma_close(struct vm_area_struct * vma)
173 {
174 }
175
176 /*
177  * Our nopage() function, maps in the actual vDSO kernel pages, they will
178  * be mapped read-only by do_no_page(), and eventually COW'ed, either
179  * right away for an initial write access, or by do_wp_page().
180  */
181 static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
182                                      unsigned long address, int *type)
183 {
184         unsigned long offset = address - vma->vm_start;
185         struct page *pg;
186 #ifdef CONFIG_PPC64
187         void *vbase = test_thread_flag(TIF_32BIT) ?
188                 vdso32_kbase : vdso64_kbase;
189 #else
190         void *vbase = vdso32_kbase;
191 #endif
192
193         DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
194             current->comm, address, offset);
195
196         if (address < vma->vm_start || address > vma->vm_end)
197                 return NOPAGE_SIGBUS;
198
199         /*
200          * Last page is systemcfg.
201          */
202         if ((vma->vm_end - address) <= PAGE_SIZE)
203                 pg = virt_to_page(vdso_data);
204         else
205                 pg = virt_to_page(vbase + offset);
206
207         get_page(pg);
208         DBG(" ->page count: %d\n", page_count(pg));
209
210         return pg;
211 }
212
213 static struct vm_operations_struct vdso_vmops = {
214         .close  = vdso_vma_close,
215         .nopage = vdso_vma_nopage,
216 };
217
218 /*
219  * This is called from binfmt_elf, we create the special vma for the
220  * vDSO and insert it into the mm struct tree
221  */
222 int arch_setup_additional_pages(struct linux_binprm *bprm,
223                                 int executable_stack)
224 {
225         struct mm_struct *mm = current->mm;
226         struct vm_area_struct *vma;
227         unsigned long vdso_pages;
228         unsigned long vdso_base;
229
230 #ifdef CONFIG_PPC64
231         if (test_thread_flag(TIF_32BIT)) {
232                 vdso_pages = vdso32_pages;
233                 vdso_base = VDSO32_MBASE;
234         } else {
235                 vdso_pages = vdso64_pages;
236                 vdso_base = VDSO64_MBASE;
237         }
238 #else
239         vdso_pages = vdso32_pages;
240         vdso_base = VDSO32_MBASE;
241 #endif
242
243         current->thread.vdso_base = 0;
244
245         /* vDSO has a problem and was disabled, just don't "enable" it for the
246          * process
247          */
248         if (vdso_pages == 0)
249                 return 0;
250
251         vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
252         if (vma == NULL)
253                 return -ENOMEM;
254
255         memset(vma, 0, sizeof(*vma));
256
257         /* Add a page to the vdso size for the data page */
258         vdso_pages ++;
259
260         /*
261          * pick a base address for the vDSO in process space. We try to put it
262          * at vdso_base which is the "natural" base for it, but we might fail
263          * and end up putting it elsewhere.
264          */
265         vdso_base = get_unmapped_area(NULL, vdso_base,
266                                       vdso_pages << PAGE_SHIFT, 0, 0);
267         if (vdso_base & ~PAGE_MASK) {
268                 kmem_cache_free(vm_area_cachep, vma);
269                 return (int)vdso_base;
270         }
271
272         current->thread.vdso_base = vdso_base;
273
274         vma->vm_mm = mm;
275         vma->vm_start = current->thread.vdso_base;
276         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
277
278         /*
279          * our vma flags don't have VM_WRITE so by default, the process isn't
280          * allowed to write those pages.
281          * gdb can break that with ptrace interface, and thus trigger COW on
282          * those pages but it's then your responsibility to never do that on
283          * the "data" page of the vDSO or you'll stop getting kernel updates
284          * and your nice userland gettimeofday will be totally dead.
285          * It's fine to use that for setting breakpoints in the vDSO code
286          * pages though
287          */
288         vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE |
289                 VM_MAYEXEC | VM_RESERVED;
290         vma->vm_flags |= mm->def_flags;
291         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
292         vma->vm_ops = &vdso_vmops;
293
294         down_write(&mm->mmap_sem);
295         if (insert_vm_struct(mm, vma)) {
296                 up_write(&mm->mmap_sem);
297                 kmem_cache_free(vm_area_cachep, vma);
298                 return -ENOMEM;
299         }
300         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
301         up_write(&mm->mmap_sem);
302
303         return 0;
304 }
305
306 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
307                                   unsigned long *size)
308 {
309         Elf32_Shdr *sechdrs;
310         unsigned int i;
311         char *secnames;
312
313         /* Grab section headers and strings so we can tell who is who */
314         sechdrs = (void *)ehdr + ehdr->e_shoff;
315         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
316
317         /* Find the section they want */
318         for (i = 1; i < ehdr->e_shnum; i++) {
319                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
320                         if (size)
321                                 *size = sechdrs[i].sh_size;
322                         return (void *)ehdr + sechdrs[i].sh_offset;
323                 }
324         }
325         *size = 0;
326         return NULL;
327 }
328
329 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
330                                         const char *symname)
331 {
332         unsigned int i;
333         char name[MAX_SYMNAME], *c;
334
335         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
336                 if (lib->dynsym[i].st_name == 0)
337                         continue;
338                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
339                         MAX_SYMNAME);
340                 c = strchr(name, '@');
341                 if (c)
342                         *c = 0;
343                 if (strcmp(symname, name) == 0)
344                         return &lib->dynsym[i];
345         }
346         return NULL;
347 }
348
349 /* Note that we assume the section is .text and the symbol is relative to
350  * the library base
351  */
352 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
353                                             const char *symname)
354 {
355         Elf32_Sym *sym = find_symbol32(lib, symname);
356
357         if (sym == NULL) {
358                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
359                        symname);
360                 return 0;
361         }
362         return sym->st_value - VDSO32_LBASE;
363 }
364
365 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
366                                 struct lib64_elfinfo *v64,
367                                 const char *orig, const char *fix)
368 {
369         Elf32_Sym *sym32_gen, *sym32_fix;
370
371         sym32_gen = find_symbol32(v32, orig);
372         if (sym32_gen == NULL) {
373                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
374                 return -1;
375         }
376         if (fix == NULL) {
377                 sym32_gen->st_name = 0;
378                 return 0;
379         }
380         sym32_fix = find_symbol32(v32, fix);
381         if (sym32_fix == NULL) {
382                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
383                 return -1;
384         }
385         sym32_gen->st_value = sym32_fix->st_value;
386         sym32_gen->st_size = sym32_fix->st_size;
387         sym32_gen->st_info = sym32_fix->st_info;
388         sym32_gen->st_other = sym32_fix->st_other;
389         sym32_gen->st_shndx = sym32_fix->st_shndx;
390
391         return 0;
392 }
393
394
395 #ifdef CONFIG_PPC64
396
397 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
398                                   unsigned long *size)
399 {
400         Elf64_Shdr *sechdrs;
401         unsigned int i;
402         char *secnames;
403
404         /* Grab section headers and strings so we can tell who is who */
405         sechdrs = (void *)ehdr + ehdr->e_shoff;
406         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
407
408         /* Find the section they want */
409         for (i = 1; i < ehdr->e_shnum; i++) {
410                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
411                         if (size)
412                                 *size = sechdrs[i].sh_size;
413                         return (void *)ehdr + sechdrs[i].sh_offset;
414                 }
415         }
416         if (size)
417                 *size = 0;
418         return NULL;
419 }
420
421 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
422                                         const char *symname)
423 {
424         unsigned int i;
425         char name[MAX_SYMNAME], *c;
426
427         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
428                 if (lib->dynsym[i].st_name == 0)
429                         continue;
430                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
431                         MAX_SYMNAME);
432                 c = strchr(name, '@');
433                 if (c)
434                         *c = 0;
435                 if (strcmp(symname, name) == 0)
436                         return &lib->dynsym[i];
437         }
438         return NULL;
439 }
440
441 /* Note that we assume the section is .text and the symbol is relative to
442  * the library base
443  */
444 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
445                                             const char *symname)
446 {
447         Elf64_Sym *sym = find_symbol64(lib, symname);
448
449         if (sym == NULL) {
450                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
451                        symname);
452                 return 0;
453         }
454 #ifdef VDS64_HAS_DESCRIPTORS
455         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
456                 VDSO64_LBASE;
457 #else
458         return sym->st_value - VDSO64_LBASE;
459 #endif
460 }
461
462 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
463                                 struct lib64_elfinfo *v64,
464                                 const char *orig, const char *fix)
465 {
466         Elf64_Sym *sym64_gen, *sym64_fix;
467
468         sym64_gen = find_symbol64(v64, orig);
469         if (sym64_gen == NULL) {
470                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
471                 return -1;
472         }
473         if (fix == NULL) {
474                 sym64_gen->st_name = 0;
475                 return 0;
476         }
477         sym64_fix = find_symbol64(v64, fix);
478         if (sym64_fix == NULL) {
479                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
480                 return -1;
481         }
482         sym64_gen->st_value = sym64_fix->st_value;
483         sym64_gen->st_size = sym64_fix->st_size;
484         sym64_gen->st_info = sym64_fix->st_info;
485         sym64_gen->st_other = sym64_fix->st_other;
486         sym64_gen->st_shndx = sym64_fix->st_shndx;
487
488         return 0;
489 }
490
491 #endif /* CONFIG_PPC64 */
492
493
494 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
495                                         struct lib64_elfinfo *v64)
496 {
497         void *sect;
498
499         /*
500          * Locate symbol tables & text section
501          */
502
503         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
504         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
505         if (v32->dynsym == NULL || v32->dynstr == NULL) {
506                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
507                 return -1;
508         }
509         sect = find_section32(v32->hdr, ".text", NULL);
510         if (sect == NULL) {
511                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
512                 return -1;
513         }
514         v32->text = sect - vdso32_kbase;
515
516 #ifdef CONFIG_PPC64
517         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
518         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
519         if (v64->dynsym == NULL || v64->dynstr == NULL) {
520                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
521                 return -1;
522         }
523         sect = find_section64(v64->hdr, ".text", NULL);
524         if (sect == NULL) {
525                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
526                 return -1;
527         }
528         v64->text = sect - vdso64_kbase;
529 #endif /* CONFIG_PPC64 */
530
531         return 0;
532 }
533
534 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
535                                           struct lib64_elfinfo *v64)
536 {
537         /*
538          * Find signal trampolines
539          */
540
541 #ifdef CONFIG_PPC64
542         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
543 #endif
544         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
545         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
546 }
547
548 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
549                                        struct lib64_elfinfo *v64)
550 {
551         Elf32_Sym *sym32;
552 #ifdef CONFIG_PPC64
553         Elf64_Sym *sym64;
554
555         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
556         if (sym64 == NULL) {
557                 printk(KERN_ERR "vDSO64: Can't find symbol "
558                        "__kernel_datapage_offset !\n");
559                 return -1;
560         }
561         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
562                 (vdso64_pages << PAGE_SHIFT) -
563                 (sym64->st_value - VDSO64_LBASE);
564 #endif /* CONFIG_PPC64 */
565
566         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
567         if (sym32 == NULL) {
568                 printk(KERN_ERR "vDSO32: Can't find symbol "
569                        "__kernel_datapage_offset !\n");
570                 return -1;
571         }
572         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
573                 (vdso32_pages << PAGE_SHIFT) -
574                 (sym32->st_value - VDSO32_LBASE);
575
576         return 0;
577 }
578
579 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
580                                        struct lib64_elfinfo *v64)
581 {
582         int i;
583
584         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
585                 struct vdso_patch_def *patch = &vdso_patches[i];
586                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
587                         == patch->ftr_value;
588                 if (!match)
589                         continue;
590
591                 DBG("replacing %s with %s...\n", patch->gen_name,
592                     patch->fix_name ? "NONE" : patch->fix_name);
593
594                 /*
595                  * Patch the 32 bits and 64 bits symbols. Note that we do not
596                  * patch the "." symbol on 64 bits.
597                  * It would be easy to do, but doesn't seem to be necessary,
598                  * patching the OPD symbol is enough.
599                  */
600                 vdso_do_func_patch32(v32, v64, patch->gen_name,
601                                      patch->fix_name);
602 #ifdef CONFIG_PPC64
603                 vdso_do_func_patch64(v32, v64, patch->gen_name,
604                                      patch->fix_name);
605 #endif /* CONFIG_PPC64 */
606         }
607
608         return 0;
609 }
610
611
612 static __init int vdso_setup(void)
613 {
614         struct lib32_elfinfo    v32;
615         struct lib64_elfinfo    v64;
616
617         v32.hdr = vdso32_kbase;
618 #ifdef CONFIG_PPC64
619         v64.hdr = vdso64_kbase;
620 #endif
621         if (vdso_do_find_sections(&v32, &v64))
622                 return -1;
623
624         if (vdso_fixup_datapage(&v32, &v64))
625                 return -1;
626
627         if (vdso_fixup_alt_funcs(&v32, &v64))
628                 return -1;
629
630         vdso_setup_trampolines(&v32, &v64);
631
632         return 0;
633 }
634
635 /*
636  * Called from setup_arch to initialize the bitmap of available
637  * syscalls in the systemcfg page
638  */
639 static void __init vdso_setup_syscall_map(void)
640 {
641         unsigned int i;
642         extern unsigned long *sys_call_table;
643         extern unsigned long sys_ni_syscall;
644
645
646         for (i = 0; i < __NR_syscalls; i++) {
647 #ifdef CONFIG_PPC64
648                 if (sys_call_table[i*2] != sys_ni_syscall)
649                         vdso_data->syscall_map_64[i >> 5] |=
650                                 0x80000000UL >> (i & 0x1f);
651                 if (sys_call_table[i*2+1] != sys_ni_syscall)
652                         vdso_data->syscall_map_32[i >> 5] |=
653                                 0x80000000UL >> (i & 0x1f);
654 #else /* CONFIG_PPC64 */
655                 if (sys_call_table[i] != sys_ni_syscall)
656                         vdso_data->syscall_map_32[i >> 5] |=
657                                 0x80000000UL >> (i & 0x1f);
658 #endif /* CONFIG_PPC64 */
659         }
660 }
661
662
663 void __init vdso_init(void)
664 {
665         int i;
666
667 #ifdef CONFIG_PPC64
668         /*
669          * Fill up the "systemcfg" stuff for backward compatiblity
670          */
671         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
672         vdso_data->version.major = SYSTEMCFG_MAJOR;
673         vdso_data->version.minor = SYSTEMCFG_MINOR;
674         vdso_data->processor = mfspr(SPRN_PVR);
675         vdso_data->platform = _machine;
676         vdso_data->physicalMemorySize = lmb_phys_mem_size();
677         vdso_data->dcache_size = ppc64_caches.dsize;
678         vdso_data->dcache_line_size = ppc64_caches.dline_size;
679         vdso_data->icache_size = ppc64_caches.isize;
680         vdso_data->icache_line_size = ppc64_caches.iline_size;
681
682         /*
683          * Calculate the size of the 64 bits vDSO
684          */
685         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
686         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
687 #endif /* CONFIG_PPC64 */
688
689
690         /*
691          * Calculate the size of the 32 bits vDSO
692          */
693         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
694         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
695
696
697         /*
698          * Setup the syscall map in the vDOS
699          */
700         vdso_setup_syscall_map();
701         /*
702          * Initialize the vDSO images in memory, that is do necessary
703          * fixups of vDSO symbols, locate trampolines, etc...
704          */
705         if (vdso_setup()) {
706                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
707                 vdso32_pages = 0;
708 #ifdef CONFIG_PPC64
709                 vdso64_pages = 0;
710 #endif
711                 return;
712         }
713
714         /* Make sure pages are in the correct state */
715         for (i = 0; i < vdso32_pages; i++) {
716                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
717                 ClearPageReserved(pg);
718                 get_page(pg);
719
720         }
721 #ifdef CONFIG_PPC64
722         for (i = 0; i < vdso64_pages; i++) {
723                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
724                 ClearPageReserved(pg);
725                 get_page(pg);
726         }
727 #endif /* CONFIG_PPC64 */
728
729         get_page(virt_to_page(vdso_data));
730 }
731
732 int in_gate_area_no_task(unsigned long addr)
733 {
734         return 0;
735 }
736
737 int in_gate_area(struct task_struct *task, unsigned long addr)
738 {
739         return 0;
740 }
741
742 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
743 {
744         return NULL;
745 }
746