[PATCH] powerpc: Unify mem= handling
[linux-2.6] / 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/config.h>
12 #include <linux/module.h>
13 #include <linux/errno.h>
14 #include <linux/sched.h>
15 #include <linux/kernel.h>
16 #include <linux/mm.h>
17 #include <linux/smp.h>
18 #include <linux/smp_lock.h>
19 #include <linux/stddef.h>
20 #include <linux/unistd.h>
21 #include <linux/slab.h>
22 #include <linux/user.h>
23 #include <linux/elf.h>
24 #include <linux/security.h>
25 #include <linux/bootmem.h>
26
27 #include <asm/pgtable.h>
28 #include <asm/system.h>
29 #include <asm/processor.h>
30 #include <asm/mmu.h>
31 #include <asm/mmu_context.h>
32 #include <asm/lmb.h>
33 #include <asm/machdep.h>
34 #include <asm/cputable.h>
35 #include <asm/sections.h>
36 #include <asm/firmware.h>
37 #include <asm/vdso.h>
38 #include <asm/vdso_datapage.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 extern char vdso32_start, vdso32_end;
52 static void *vdso32_kbase = &vdso32_start;
53 unsigned int vdso32_pages;
54 unsigned long vdso32_sigtramp;
55 unsigned long vdso32_rt_sigtramp;
56
57 #ifdef CONFIG_PPC64
58 extern char vdso64_start, vdso64_end;
59 static void *vdso64_kbase = &vdso64_start;
60 unsigned int vdso64_pages;
61 unsigned long vdso64_rt_sigtramp;
62 #endif /* CONFIG_PPC64 */
63
64 /*
65  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
66  * Once the early boot kernel code no longer needs to muck around
67  * with it, it will become dynamically allocated
68  */
69 static union {
70         struct vdso_data        data;
71         u8                      page[PAGE_SIZE];
72 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
73 struct vdso_data *vdso_data = &vdso_data_store.data;
74
75 /* Format of the patch table */
76 struct vdso_patch_def
77 {
78         unsigned long   ftr_mask, ftr_value;
79         const char      *gen_name;
80         const char      *fix_name;
81 };
82
83 /* Table of functions to patch based on the CPU type/revision
84  *
85  * Currently, we only change sync_dicache to do nothing on processors
86  * with a coherent icache
87  */
88 static struct vdso_patch_def vdso_patches[] = {
89         {
90                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
91                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
92         },
93         {
94                 CPU_FTR_USE_TB, 0,
95                 "__kernel_gettimeofday", NULL
96         },
97 };
98
99 /*
100  * Some infos carried around for each of them during parsing at
101  * boot time.
102  */
103 struct lib32_elfinfo
104 {
105         Elf32_Ehdr      *hdr;           /* ptr to ELF */
106         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
107         unsigned long   dynsymsize;     /* size of .dynsym section */
108         char            *dynstr;        /* ptr to .dynstr section */
109         unsigned long   text;           /* offset of .text section in .so */
110 };
111
112 struct lib64_elfinfo
113 {
114         Elf64_Ehdr      *hdr;
115         Elf64_Sym       *dynsym;
116         unsigned long   dynsymsize;
117         char            *dynstr;
118         unsigned long   text;
119 };
120
121
122 #ifdef __DEBUG
123 static void dump_one_vdso_page(struct page *pg, struct page *upg)
124 {
125         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
126                page_count(pg),
127                pg->flags);
128         if (upg/* && pg != upg*/) {
129                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
130                                                        << PAGE_SHIFT),
131                        page_count(upg),
132                        upg->flags);
133         }
134         printk("\n");
135 }
136
137 static void dump_vdso_pages(struct vm_area_struct * vma)
138 {
139         int i;
140
141         if (!vma || test_thread_flag(TIF_32BIT)) {
142                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
143                 for (i=0; i<vdso32_pages; i++) {
144                         struct page *pg = virt_to_page(vdso32_kbase +
145                                                        i*PAGE_SIZE);
146                         struct page *upg = (vma && vma->vm_mm) ?
147                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
148                                 : NULL;
149                         dump_one_vdso_page(pg, upg);
150                 }
151         }
152         if (!vma || !test_thread_flag(TIF_32BIT)) {
153                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
154                 for (i=0; i<vdso64_pages; i++) {
155                         struct page *pg = virt_to_page(vdso64_kbase +
156                                                        i*PAGE_SIZE);
157                         struct page *upg = (vma && vma->vm_mm) ?
158                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
159                                 : NULL;
160                         dump_one_vdso_page(pg, upg);
161                 }
162         }
163 }
164 #endif /* DEBUG */
165
166 /*
167  * Keep a dummy vma_close for now, it will prevent VMA merging.
168  */
169 static void vdso_vma_close(struct vm_area_struct * vma)
170 {
171 }
172
173 /*
174  * Our nopage() function, maps in the actual vDSO kernel pages, they will
175  * be mapped read-only by do_no_page(), and eventually COW'ed, either
176  * right away for an initial write access, or by do_wp_page().
177  */
178 static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
179                                      unsigned long address, int *type)
180 {
181         unsigned long offset = address - vma->vm_start;
182         struct page *pg;
183 #ifdef CONFIG_PPC64
184         void *vbase = (vma->vm_mm->task_size > TASK_SIZE_USER32) ?
185                 vdso64_kbase : vdso32_kbase;
186 #else
187         void *vbase = vdso32_kbase;
188 #endif
189
190         DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
191             current->comm, address, offset);
192
193         if (address < vma->vm_start || address > vma->vm_end)
194                 return NOPAGE_SIGBUS;
195
196         /*
197          * Last page is systemcfg.
198          */
199         if ((vma->vm_end - address) <= PAGE_SIZE)
200                 pg = virt_to_page(vdso_data);
201         else
202                 pg = virt_to_page(vbase + offset);
203
204         get_page(pg);
205         DBG(" ->page count: %d\n", page_count(pg));
206
207         return pg;
208 }
209
210 static struct vm_operations_struct vdso_vmops = {
211         .close  = vdso_vma_close,
212         .nopage = vdso_vma_nopage,
213 };
214
215 /*
216  * This is called from binfmt_elf, we create the special vma for the
217  * vDSO and insert it into the mm struct tree
218  */
219 int arch_setup_additional_pages(struct linux_binprm *bprm,
220                                 int executable_stack)
221 {
222         struct mm_struct *mm = current->mm;
223         struct vm_area_struct *vma;
224         unsigned long vdso_pages;
225         unsigned long vdso_base;
226
227 #ifdef CONFIG_PPC64
228         if (test_thread_flag(TIF_32BIT)) {
229                 vdso_pages = vdso32_pages;
230                 vdso_base = VDSO32_MBASE;
231         } else {
232                 vdso_pages = vdso64_pages;
233                 vdso_base = VDSO64_MBASE;
234         }
235 #else
236         vdso_pages = vdso32_pages;
237         vdso_base = VDSO32_MBASE;
238 #endif
239
240         current->thread.vdso_base = 0;
241
242         /* vDSO has a problem and was disabled, just don't "enable" it for the
243          * process
244          */
245         if (vdso_pages == 0)
246                 return 0;
247
248         vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
249         if (vma == NULL)
250                 return -ENOMEM;
251
252         memset(vma, 0, sizeof(*vma));
253
254         /* Add a page to the vdso size for the data page */
255         vdso_pages ++;
256
257         /*
258          * pick a base address for the vDSO in process space. We try to put it
259          * at vdso_base which is the "natural" base for it, but we might fail
260          * and end up putting it elsewhere.
261          */
262         vdso_base = get_unmapped_area(NULL, vdso_base,
263                                       vdso_pages << PAGE_SHIFT, 0, 0);
264         if (vdso_base & ~PAGE_MASK) {
265                 kmem_cache_free(vm_area_cachep, vma);
266                 return (int)vdso_base;
267         }
268
269         current->thread.vdso_base = vdso_base;
270
271         vma->vm_mm = mm;
272         vma->vm_start = current->thread.vdso_base;
273         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
274
275         /*
276          * our vma flags don't have VM_WRITE so by default, the process isn't
277          * allowed to write those pages.
278          * gdb can break that with ptrace interface, and thus trigger COW on
279          * those pages but it's then your responsibility to never do that on
280          * the "data" page of the vDSO or you'll stop getting kernel updates
281          * and your nice userland gettimeofday will be totally dead.
282          * It's fine to use that for setting breakpoints in the vDSO code
283          * pages though
284          */
285         vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
286         vma->vm_flags |= mm->def_flags;
287         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
288         vma->vm_ops = &vdso_vmops;
289
290         down_write(&mm->mmap_sem);
291         if (insert_vm_struct(mm, vma)) {
292                 up_write(&mm->mmap_sem);
293                 kmem_cache_free(vm_area_cachep, vma);
294                 return -ENOMEM;
295         }
296         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
297         up_write(&mm->mmap_sem);
298
299         return 0;
300 }
301
302 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
303                                   unsigned long *size)
304 {
305         Elf32_Shdr *sechdrs;
306         unsigned int i;
307         char *secnames;
308
309         /* Grab section headers and strings so we can tell who is who */
310         sechdrs = (void *)ehdr + ehdr->e_shoff;
311         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
312
313         /* Find the section they want */
314         for (i = 1; i < ehdr->e_shnum; i++) {
315                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
316                         if (size)
317                                 *size = sechdrs[i].sh_size;
318                         return (void *)ehdr + sechdrs[i].sh_offset;
319                 }
320         }
321         *size = 0;
322         return NULL;
323 }
324
325 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
326                                         const char *symname)
327 {
328         unsigned int i;
329         char name[MAX_SYMNAME], *c;
330
331         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
332                 if (lib->dynsym[i].st_name == 0)
333                         continue;
334                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
335                         MAX_SYMNAME);
336                 c = strchr(name, '@');
337                 if (c)
338                         *c = 0;
339                 if (strcmp(symname, name) == 0)
340                         return &lib->dynsym[i];
341         }
342         return NULL;
343 }
344
345 /* Note that we assume the section is .text and the symbol is relative to
346  * the library base
347  */
348 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
349                                             const char *symname)
350 {
351         Elf32_Sym *sym = find_symbol32(lib, symname);
352
353         if (sym == NULL) {
354                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
355                        symname);
356                 return 0;
357         }
358         return sym->st_value - VDSO32_LBASE;
359 }
360
361 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
362                                 struct lib64_elfinfo *v64,
363                                 const char *orig, const char *fix)
364 {
365         Elf32_Sym *sym32_gen, *sym32_fix;
366
367         sym32_gen = find_symbol32(v32, orig);
368         if (sym32_gen == NULL) {
369                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
370                 return -1;
371         }
372         if (fix == NULL) {
373                 sym32_gen->st_name = 0;
374                 return 0;
375         }
376         sym32_fix = find_symbol32(v32, fix);
377         if (sym32_fix == NULL) {
378                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
379                 return -1;
380         }
381         sym32_gen->st_value = sym32_fix->st_value;
382         sym32_gen->st_size = sym32_fix->st_size;
383         sym32_gen->st_info = sym32_fix->st_info;
384         sym32_gen->st_other = sym32_fix->st_other;
385         sym32_gen->st_shndx = sym32_fix->st_shndx;
386
387         return 0;
388 }
389
390
391 #ifdef CONFIG_PPC64
392
393 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
394                                   unsigned long *size)
395 {
396         Elf64_Shdr *sechdrs;
397         unsigned int i;
398         char *secnames;
399
400         /* Grab section headers and strings so we can tell who is who */
401         sechdrs = (void *)ehdr + ehdr->e_shoff;
402         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
403
404         /* Find the section they want */
405         for (i = 1; i < ehdr->e_shnum; i++) {
406                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
407                         if (size)
408                                 *size = sechdrs[i].sh_size;
409                         return (void *)ehdr + sechdrs[i].sh_offset;
410                 }
411         }
412         if (size)
413                 *size = 0;
414         return NULL;
415 }
416
417 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
418                                         const char *symname)
419 {
420         unsigned int i;
421         char name[MAX_SYMNAME], *c;
422
423         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
424                 if (lib->dynsym[i].st_name == 0)
425                         continue;
426                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
427                         MAX_SYMNAME);
428                 c = strchr(name, '@');
429                 if (c)
430                         *c = 0;
431                 if (strcmp(symname, name) == 0)
432                         return &lib->dynsym[i];
433         }
434         return NULL;
435 }
436
437 /* Note that we assume the section is .text and the symbol is relative to
438  * the library base
439  */
440 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
441                                             const char *symname)
442 {
443         Elf64_Sym *sym = find_symbol64(lib, symname);
444
445         if (sym == NULL) {
446                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
447                        symname);
448                 return 0;
449         }
450 #ifdef VDS64_HAS_DESCRIPTORS
451         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
452                 VDSO64_LBASE;
453 #else
454         return sym->st_value - VDSO64_LBASE;
455 #endif
456 }
457
458 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
459                                 struct lib64_elfinfo *v64,
460                                 const char *orig, const char *fix)
461 {
462         Elf64_Sym *sym64_gen, *sym64_fix;
463
464         sym64_gen = find_symbol64(v64, orig);
465         if (sym64_gen == NULL) {
466                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
467                 return -1;
468         }
469         if (fix == NULL) {
470                 sym64_gen->st_name = 0;
471                 return 0;
472         }
473         sym64_fix = find_symbol64(v64, fix);
474         if (sym64_fix == NULL) {
475                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
476                 return -1;
477         }
478         sym64_gen->st_value = sym64_fix->st_value;
479         sym64_gen->st_size = sym64_fix->st_size;
480         sym64_gen->st_info = sym64_fix->st_info;
481         sym64_gen->st_other = sym64_fix->st_other;
482         sym64_gen->st_shndx = sym64_fix->st_shndx;
483
484         return 0;
485 }
486
487 #endif /* CONFIG_PPC64 */
488
489
490 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
491                                         struct lib64_elfinfo *v64)
492 {
493         void *sect;
494
495         /*
496          * Locate symbol tables & text section
497          */
498
499         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
500         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
501         if (v32->dynsym == NULL || v32->dynstr == NULL) {
502                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
503                 return -1;
504         }
505         sect = find_section32(v32->hdr, ".text", NULL);
506         if (sect == NULL) {
507                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
508                 return -1;
509         }
510         v32->text = sect - vdso32_kbase;
511
512 #ifdef CONFIG_PPC64
513         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
514         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
515         if (v64->dynsym == NULL || v64->dynstr == NULL) {
516                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
517                 return -1;
518         }
519         sect = find_section64(v64->hdr, ".text", NULL);
520         if (sect == NULL) {
521                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
522                 return -1;
523         }
524         v64->text = sect - vdso64_kbase;
525 #endif /* CONFIG_PPC64 */
526
527         return 0;
528 }
529
530 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
531                                           struct lib64_elfinfo *v64)
532 {
533         /*
534          * Find signal trampolines
535          */
536
537 #ifdef CONFIG_PPC64
538         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
539 #endif
540         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
541         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
542 }
543
544 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
545                                        struct lib64_elfinfo *v64)
546 {
547         Elf32_Sym *sym32;
548 #ifdef CONFIG_PPC64
549         Elf64_Sym *sym64;
550
551         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
552         if (sym64 == NULL) {
553                 printk(KERN_ERR "vDSO64: Can't find symbol "
554                        "__kernel_datapage_offset !\n");
555                 return -1;
556         }
557         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
558                 (vdso64_pages << PAGE_SHIFT) -
559                 (sym64->st_value - VDSO64_LBASE);
560 #endif /* CONFIG_PPC64 */
561
562         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
563         if (sym32 == NULL) {
564                 printk(KERN_ERR "vDSO32: Can't find symbol "
565                        "__kernel_datapage_offset !\n");
566                 return -1;
567         }
568         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
569                 (vdso32_pages << PAGE_SHIFT) -
570                 (sym32->st_value - VDSO32_LBASE);
571
572         return 0;
573 }
574
575 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
576                                        struct lib64_elfinfo *v64)
577 {
578         int i;
579
580         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
581                 struct vdso_patch_def *patch = &vdso_patches[i];
582                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
583                         == patch->ftr_value;
584                 if (!match)
585                         continue;
586
587                 DBG("replacing %s with %s...\n", patch->gen_name,
588                     patch->fix_name ? "NONE" : patch->fix_name);
589
590                 /*
591                  * Patch the 32 bits and 64 bits symbols. Note that we do not
592                  * patch the "." symbol on 64 bits.
593                  * It would be easy to do, but doesn't seem to be necessary,
594                  * patching the OPD symbol is enough.
595                  */
596                 vdso_do_func_patch32(v32, v64, patch->gen_name,
597                                      patch->fix_name);
598 #ifdef CONFIG_PPC64
599                 vdso_do_func_patch64(v32, v64, patch->gen_name,
600                                      patch->fix_name);
601 #endif /* CONFIG_PPC64 */
602         }
603
604         return 0;
605 }
606
607
608 static __init int vdso_setup(void)
609 {
610         struct lib32_elfinfo    v32;
611         struct lib64_elfinfo    v64;
612
613         v32.hdr = vdso32_kbase;
614 #ifdef CONFIG_PPC64
615         v64.hdr = vdso64_kbase;
616 #endif
617         if (vdso_do_find_sections(&v32, &v64))
618                 return -1;
619
620         if (vdso_fixup_datapage(&v32, &v64))
621                 return -1;
622
623         if (vdso_fixup_alt_funcs(&v32, &v64))
624                 return -1;
625
626         vdso_setup_trampolines(&v32, &v64);
627
628         return 0;
629 }
630
631 /*
632  * Called from setup_arch to initialize the bitmap of available
633  * syscalls in the systemcfg page
634  */
635 static void __init vdso_setup_syscall_map(void)
636 {
637         unsigned int i;
638         extern unsigned long *sys_call_table;
639         extern unsigned long sys_ni_syscall;
640
641
642         for (i = 0; i < __NR_syscalls; i++) {
643 #ifdef CONFIG_PPC64
644                 if (sys_call_table[i*2] != sys_ni_syscall)
645                         vdso_data->syscall_map_64[i >> 5] |=
646                                 0x80000000UL >> (i & 0x1f);
647                 if (sys_call_table[i*2+1] != sys_ni_syscall)
648                         vdso_data->syscall_map_32[i >> 5] |=
649                                 0x80000000UL >> (i & 0x1f);
650 #else /* CONFIG_PPC64 */
651                 if (sys_call_table[i] != sys_ni_syscall)
652                         vdso_data->syscall_map_32[i >> 5] |=
653                                 0x80000000UL >> (i & 0x1f);
654 #endif /* CONFIG_PPC64 */
655         }
656 }
657
658
659 void __init vdso_init(void)
660 {
661         int i;
662
663 #ifdef CONFIG_PPC64
664         /*
665          * Fill up the "systemcfg" stuff for backward compatiblity
666          */
667         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
668         vdso_data->version.major = SYSTEMCFG_MAJOR;
669         vdso_data->version.minor = SYSTEMCFG_MINOR;
670         vdso_data->processor = mfspr(SPRN_PVR);
671         /*
672          * Fake the old platform number for pSeries and iSeries and add
673          * in LPAR bit if necessary
674          */
675         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
676         if (firmware_has_feature(FW_FEATURE_LPAR))
677                 vdso_data->platform |= 1;
678         vdso_data->physicalMemorySize = lmb_phys_mem_size();
679         vdso_data->dcache_size = ppc64_caches.dsize;
680         vdso_data->dcache_line_size = ppc64_caches.dline_size;
681         vdso_data->icache_size = ppc64_caches.isize;
682         vdso_data->icache_line_size = ppc64_caches.iline_size;
683
684         /*
685          * Calculate the size of the 64 bits vDSO
686          */
687         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
688         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
689 #endif /* CONFIG_PPC64 */
690
691
692         /*
693          * Calculate the size of the 32 bits vDSO
694          */
695         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
696         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
697
698
699         /*
700          * Setup the syscall map in the vDOS
701          */
702         vdso_setup_syscall_map();
703         /*
704          * Initialize the vDSO images in memory, that is do necessary
705          * fixups of vDSO symbols, locate trampolines, etc...
706          */
707         if (vdso_setup()) {
708                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
709                 vdso32_pages = 0;
710 #ifdef CONFIG_PPC64
711                 vdso64_pages = 0;
712 #endif
713                 return;
714         }
715
716         /* Make sure pages are in the correct state */
717         for (i = 0; i < vdso32_pages; i++) {
718                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
719                 ClearPageReserved(pg);
720                 get_page(pg);
721
722         }
723 #ifdef CONFIG_PPC64
724         for (i = 0; i < vdso64_pages; i++) {
725                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
726                 ClearPageReserved(pg);
727                 get_page(pg);
728         }
729 #endif /* CONFIG_PPC64 */
730
731         get_page(virt_to_page(vdso_data));
732 }
733
734 int in_gate_area_no_task(unsigned long addr)
735 {
736         return 0;
737 }
738
739 int in_gate_area(struct task_struct *task, unsigned long addr)
740 {
741         return 0;
742 }
743
744 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
745 {
746         return NULL;
747 }
748