[PATCH] unpaged: VM_UNPAGED
[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 | VM_MAYEXEC;
289         vma->vm_flags |= mm->def_flags;
290         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
291         vma->vm_ops = &vdso_vmops;
292
293         down_write(&mm->mmap_sem);
294         if (insert_vm_struct(mm, vma)) {
295                 up_write(&mm->mmap_sem);
296                 kmem_cache_free(vm_area_cachep, vma);
297                 return -ENOMEM;
298         }
299         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
300         up_write(&mm->mmap_sem);
301
302         return 0;
303 }
304
305 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
306                                   unsigned long *size)
307 {
308         Elf32_Shdr *sechdrs;
309         unsigned int i;
310         char *secnames;
311
312         /* Grab section headers and strings so we can tell who is who */
313         sechdrs = (void *)ehdr + ehdr->e_shoff;
314         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
315
316         /* Find the section they want */
317         for (i = 1; i < ehdr->e_shnum; i++) {
318                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
319                         if (size)
320                                 *size = sechdrs[i].sh_size;
321                         return (void *)ehdr + sechdrs[i].sh_offset;
322                 }
323         }
324         *size = 0;
325         return NULL;
326 }
327
328 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
329                                         const char *symname)
330 {
331         unsigned int i;
332         char name[MAX_SYMNAME], *c;
333
334         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
335                 if (lib->dynsym[i].st_name == 0)
336                         continue;
337                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
338                         MAX_SYMNAME);
339                 c = strchr(name, '@');
340                 if (c)
341                         *c = 0;
342                 if (strcmp(symname, name) == 0)
343                         return &lib->dynsym[i];
344         }
345         return NULL;
346 }
347
348 /* Note that we assume the section is .text and the symbol is relative to
349  * the library base
350  */
351 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
352                                             const char *symname)
353 {
354         Elf32_Sym *sym = find_symbol32(lib, symname);
355
356         if (sym == NULL) {
357                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
358                        symname);
359                 return 0;
360         }
361         return sym->st_value - VDSO32_LBASE;
362 }
363
364 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
365                                 struct lib64_elfinfo *v64,
366                                 const char *orig, const char *fix)
367 {
368         Elf32_Sym *sym32_gen, *sym32_fix;
369
370         sym32_gen = find_symbol32(v32, orig);
371         if (sym32_gen == NULL) {
372                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
373                 return -1;
374         }
375         if (fix == NULL) {
376                 sym32_gen->st_name = 0;
377                 return 0;
378         }
379         sym32_fix = find_symbol32(v32, fix);
380         if (sym32_fix == NULL) {
381                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
382                 return -1;
383         }
384         sym32_gen->st_value = sym32_fix->st_value;
385         sym32_gen->st_size = sym32_fix->st_size;
386         sym32_gen->st_info = sym32_fix->st_info;
387         sym32_gen->st_other = sym32_fix->st_other;
388         sym32_gen->st_shndx = sym32_fix->st_shndx;
389
390         return 0;
391 }
392
393
394 #ifdef CONFIG_PPC64
395
396 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
397                                   unsigned long *size)
398 {
399         Elf64_Shdr *sechdrs;
400         unsigned int i;
401         char *secnames;
402
403         /* Grab section headers and strings so we can tell who is who */
404         sechdrs = (void *)ehdr + ehdr->e_shoff;
405         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
406
407         /* Find the section they want */
408         for (i = 1; i < ehdr->e_shnum; i++) {
409                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
410                         if (size)
411                                 *size = sechdrs[i].sh_size;
412                         return (void *)ehdr + sechdrs[i].sh_offset;
413                 }
414         }
415         if (size)
416                 *size = 0;
417         return NULL;
418 }
419
420 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
421                                         const char *symname)
422 {
423         unsigned int i;
424         char name[MAX_SYMNAME], *c;
425
426         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
427                 if (lib->dynsym[i].st_name == 0)
428                         continue;
429                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
430                         MAX_SYMNAME);
431                 c = strchr(name, '@');
432                 if (c)
433                         *c = 0;
434                 if (strcmp(symname, name) == 0)
435                         return &lib->dynsym[i];
436         }
437         return NULL;
438 }
439
440 /* Note that we assume the section is .text and the symbol is relative to
441  * the library base
442  */
443 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
444                                             const char *symname)
445 {
446         Elf64_Sym *sym = find_symbol64(lib, symname);
447
448         if (sym == NULL) {
449                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
450                        symname);
451                 return 0;
452         }
453 #ifdef VDS64_HAS_DESCRIPTORS
454         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
455                 VDSO64_LBASE;
456 #else
457         return sym->st_value - VDSO64_LBASE;
458 #endif
459 }
460
461 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
462                                 struct lib64_elfinfo *v64,
463                                 const char *orig, const char *fix)
464 {
465         Elf64_Sym *sym64_gen, *sym64_fix;
466
467         sym64_gen = find_symbol64(v64, orig);
468         if (sym64_gen == NULL) {
469                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
470                 return -1;
471         }
472         if (fix == NULL) {
473                 sym64_gen->st_name = 0;
474                 return 0;
475         }
476         sym64_fix = find_symbol64(v64, fix);
477         if (sym64_fix == NULL) {
478                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
479                 return -1;
480         }
481         sym64_gen->st_value = sym64_fix->st_value;
482         sym64_gen->st_size = sym64_fix->st_size;
483         sym64_gen->st_info = sym64_fix->st_info;
484         sym64_gen->st_other = sym64_fix->st_other;
485         sym64_gen->st_shndx = sym64_fix->st_shndx;
486
487         return 0;
488 }
489
490 #endif /* CONFIG_PPC64 */
491
492
493 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
494                                         struct lib64_elfinfo *v64)
495 {
496         void *sect;
497
498         /*
499          * Locate symbol tables & text section
500          */
501
502         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
503         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
504         if (v32->dynsym == NULL || v32->dynstr == NULL) {
505                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
506                 return -1;
507         }
508         sect = find_section32(v32->hdr, ".text", NULL);
509         if (sect == NULL) {
510                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
511                 return -1;
512         }
513         v32->text = sect - vdso32_kbase;
514
515 #ifdef CONFIG_PPC64
516         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
517         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
518         if (v64->dynsym == NULL || v64->dynstr == NULL) {
519                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
520                 return -1;
521         }
522         sect = find_section64(v64->hdr, ".text", NULL);
523         if (sect == NULL) {
524                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
525                 return -1;
526         }
527         v64->text = sect - vdso64_kbase;
528 #endif /* CONFIG_PPC64 */
529
530         return 0;
531 }
532
533 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
534                                           struct lib64_elfinfo *v64)
535 {
536         /*
537          * Find signal trampolines
538          */
539
540 #ifdef CONFIG_PPC64
541         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
542 #endif
543         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
544         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
545 }
546
547 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
548                                        struct lib64_elfinfo *v64)
549 {
550         Elf32_Sym *sym32;
551 #ifdef CONFIG_PPC64
552         Elf64_Sym *sym64;
553
554         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
555         if (sym64 == NULL) {
556                 printk(KERN_ERR "vDSO64: Can't find symbol "
557                        "__kernel_datapage_offset !\n");
558                 return -1;
559         }
560         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
561                 (vdso64_pages << PAGE_SHIFT) -
562                 (sym64->st_value - VDSO64_LBASE);
563 #endif /* CONFIG_PPC64 */
564
565         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
566         if (sym32 == NULL) {
567                 printk(KERN_ERR "vDSO32: Can't find symbol "
568                        "__kernel_datapage_offset !\n");
569                 return -1;
570         }
571         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
572                 (vdso32_pages << PAGE_SHIFT) -
573                 (sym32->st_value - VDSO32_LBASE);
574
575         return 0;
576 }
577
578 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
579                                        struct lib64_elfinfo *v64)
580 {
581         int i;
582
583         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
584                 struct vdso_patch_def *patch = &vdso_patches[i];
585                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
586                         == patch->ftr_value;
587                 if (!match)
588                         continue;
589
590                 DBG("replacing %s with %s...\n", patch->gen_name,
591                     patch->fix_name ? "NONE" : patch->fix_name);
592
593                 /*
594                  * Patch the 32 bits and 64 bits symbols. Note that we do not
595                  * patch the "." symbol on 64 bits.
596                  * It would be easy to do, but doesn't seem to be necessary,
597                  * patching the OPD symbol is enough.
598                  */
599                 vdso_do_func_patch32(v32, v64, patch->gen_name,
600                                      patch->fix_name);
601 #ifdef CONFIG_PPC64
602                 vdso_do_func_patch64(v32, v64, patch->gen_name,
603                                      patch->fix_name);
604 #endif /* CONFIG_PPC64 */
605         }
606
607         return 0;
608 }
609
610
611 static __init int vdso_setup(void)
612 {
613         struct lib32_elfinfo    v32;
614         struct lib64_elfinfo    v64;
615
616         v32.hdr = vdso32_kbase;
617 #ifdef CONFIG_PPC64
618         v64.hdr = vdso64_kbase;
619 #endif
620         if (vdso_do_find_sections(&v32, &v64))
621                 return -1;
622
623         if (vdso_fixup_datapage(&v32, &v64))
624                 return -1;
625
626         if (vdso_fixup_alt_funcs(&v32, &v64))
627                 return -1;
628
629         vdso_setup_trampolines(&v32, &v64);
630
631         return 0;
632 }
633
634 /*
635  * Called from setup_arch to initialize the bitmap of available
636  * syscalls in the systemcfg page
637  */
638 static void __init vdso_setup_syscall_map(void)
639 {
640         unsigned int i;
641         extern unsigned long *sys_call_table;
642         extern unsigned long sys_ni_syscall;
643
644
645         for (i = 0; i < __NR_syscalls; i++) {
646 #ifdef CONFIG_PPC64
647                 if (sys_call_table[i*2] != sys_ni_syscall)
648                         vdso_data->syscall_map_64[i >> 5] |=
649                                 0x80000000UL >> (i & 0x1f);
650                 if (sys_call_table[i*2+1] != sys_ni_syscall)
651                         vdso_data->syscall_map_32[i >> 5] |=
652                                 0x80000000UL >> (i & 0x1f);
653 #else /* CONFIG_PPC64 */
654                 if (sys_call_table[i] != sys_ni_syscall)
655                         vdso_data->syscall_map_32[i >> 5] |=
656                                 0x80000000UL >> (i & 0x1f);
657 #endif /* CONFIG_PPC64 */
658         }
659 }
660
661
662 void __init vdso_init(void)
663 {
664         int i;
665
666 #ifdef CONFIG_PPC64
667         /*
668          * Fill up the "systemcfg" stuff for backward compatiblity
669          */
670         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
671         vdso_data->version.major = SYSTEMCFG_MAJOR;
672         vdso_data->version.minor = SYSTEMCFG_MINOR;
673         vdso_data->processor = mfspr(SPRN_PVR);
674         vdso_data->platform = _machine;
675         vdso_data->physicalMemorySize = lmb_phys_mem_size();
676         vdso_data->dcache_size = ppc64_caches.dsize;
677         vdso_data->dcache_line_size = ppc64_caches.dline_size;
678         vdso_data->icache_size = ppc64_caches.isize;
679         vdso_data->icache_line_size = ppc64_caches.iline_size;
680
681         /*
682          * Calculate the size of the 64 bits vDSO
683          */
684         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
685         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
686 #endif /* CONFIG_PPC64 */
687
688
689         /*
690          * Calculate the size of the 32 bits vDSO
691          */
692         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
693         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
694
695
696         /*
697          * Setup the syscall map in the vDOS
698          */
699         vdso_setup_syscall_map();
700         /*
701          * Initialize the vDSO images in memory, that is do necessary
702          * fixups of vDSO symbols, locate trampolines, etc...
703          */
704         if (vdso_setup()) {
705                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
706                 vdso32_pages = 0;
707 #ifdef CONFIG_PPC64
708                 vdso64_pages = 0;
709 #endif
710                 return;
711         }
712
713         /* Make sure pages are in the correct state */
714         for (i = 0; i < vdso32_pages; i++) {
715                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
716                 ClearPageReserved(pg);
717                 get_page(pg);
718
719         }
720 #ifdef CONFIG_PPC64
721         for (i = 0; i < vdso64_pages; i++) {
722                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
723                 ClearPageReserved(pg);
724                 get_page(pg);
725         }
726 #endif /* CONFIG_PPC64 */
727
728         get_page(virt_to_page(vdso_data));
729 }
730
731 int in_gate_area_no_task(unsigned long addr)
732 {
733         return 0;
734 }
735
736 int in_gate_area(struct task_struct *task, unsigned long addr)
737 {
738         return 0;
739 }
740
741 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
742 {
743         return NULL;
744 }
745