1 // SPDX-License-Identifier: GPL-2.0-or-later
2
3 /*
4 * Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
5 * <benh@kernel.crashing.org>
6 */
7
8 #include <linux/errno.h>
9 #include <linux/sched.h>
10 #include <linux/kernel.h>
11 #include <linux/mm.h>
12 #include <linux/smp.h>
13 #include <linux/stddef.h>
14 #include <linux/unistd.h>
15 #include <linux/slab.h>
16 #include <linux/user.h>
17 #include <linux/elf.h>
18 #include <linux/security.h>
19 #include <linux/memblock.h>
20
21 #include <asm/processor.h>
22 #include <asm/mmu.h>
23 #include <asm/mmu_context.h>
24 #include <asm/prom.h>
25 #include <asm/machdep.h>
26 #include <asm/cputable.h>
27 #include <asm/sections.h>
28 #include <asm/firmware.h>
29 #include <asm/vdso.h>
30 #include <asm/vdso_datapage.h>
31 #include <asm/setup.h>
32
33 #undef DEBUG
34
35 #ifdef DEBUG
36 #define DBG(fmt...) printk(fmt)
37 #else
38 #define DBG(fmt...)
39 #endif
40
41 /* Max supported size for symbol names */
42 #define MAX_SYMNAME 64
43
44 /* The alignment of the vDSO */
45 #define VDSO_ALIGNMENT (1 << 16)
46
47 static unsigned int vdso32_pages;
48 static void *vdso32_kbase;
49 static struct page **vdso32_pagelist;
50 unsigned long vdso32_sigtramp;
51 unsigned long vdso32_rt_sigtramp;
52
53 #ifdef CONFIG_VDSO32
54 extern char vdso32_start, vdso32_end;
55 #endif
56
57 #ifdef CONFIG_PPC64
58 extern char vdso64_start, vdso64_end;
59 static void *vdso64_kbase = &vdso64_start;
60 static unsigned int vdso64_pages;
61 static struct page **vdso64_pagelist;
62 unsigned long vdso64_rt_sigtramp;
63 #endif /* CONFIG_PPC64 */
64
65 static int vdso_ready;
66
67 /*
68 * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
69 * Once the early boot kernel code no longer needs to muck around
70 * with it, it will become dynamically allocated
71 */
72 static union {
73 struct vdso_data data;
74 u8 page[PAGE_SIZE];
75 } vdso_data_store __page_aligned_data;
76 struct vdso_data *vdso_data = &vdso_data_store.data;
77
78 /* Format of the patch table */
79 struct vdso_patch_def
80 {
81 unsigned long ftr_mask, ftr_value;
82 const char *gen_name;
83 const char *fix_name;
84 };
85
86 /* Table of functions to patch based on the CPU type/revision
87 *
88 * Currently, we only change sync_dicache to do nothing on processors
89 * with a coherent icache
90 */
91 static struct vdso_patch_def vdso_patches[] = {
92 {
93 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
94 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
95 },
96 };
97
98 /*
99 * Some infos carried around for each of them during parsing at
100 * boot time.
101 */
102 struct lib32_elfinfo
103 {
104 Elf32_Ehdr *hdr; /* ptr to ELF */
105 Elf32_Sym *dynsym; /* ptr to .dynsym section */
106 unsigned long dynsymsize; /* size of .dynsym section */
107 char *dynstr; /* ptr to .dynstr section */
108 unsigned long text; /* offset of .text section in .so */
109 };
110
111 struct lib64_elfinfo
112 {
113 Elf64_Ehdr *hdr;
114 Elf64_Sym *dynsym;
115 unsigned long dynsymsize;
116 char *dynstr;
117 unsigned long text;
118 };
119
120
121 /*
122 * This is called from binfmt_elf, we create the special vma for the
123 * vDSO and insert it into the mm struct tree
124 */
arch_setup_additional_pages(struct linux_binprm * bprm,int uses_interp)125 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
126 {
127 struct mm_struct *mm = current->mm;
128 struct page **vdso_pagelist;
129 unsigned long vdso_pages;
130 unsigned long vdso_base;
131 int rc;
132
133 if (!vdso_ready)
134 return 0;
135
136 #ifdef CONFIG_PPC64
137 if (is_32bit_task()) {
138 vdso_pagelist = vdso32_pagelist;
139 vdso_pages = vdso32_pages;
140 vdso_base = VDSO32_MBASE;
141 } else {
142 vdso_pagelist = vdso64_pagelist;
143 vdso_pages = vdso64_pages;
144 /*
145 * On 64bit we don't have a preferred map address. This
146 * allows get_unmapped_area to find an area near other mmaps
147 * and most likely share a SLB entry.
148 */
149 vdso_base = 0;
150 }
151 #else
152 vdso_pagelist = vdso32_pagelist;
153 vdso_pages = vdso32_pages;
154 vdso_base = VDSO32_MBASE;
155 #endif
156
157 current->mm->context.vdso_base = 0;
158
159 /* vDSO has a problem and was disabled, just don't "enable" it for the
160 * process
161 */
162 if (vdso_pages == 0)
163 return 0;
164 /* Add a page to the vdso size for the data page */
165 vdso_pages ++;
166
167 /*
168 * pick a base address for the vDSO in process space. We try to put it
169 * at vdso_base which is the "natural" base for it, but we might fail
170 * and end up putting it elsewhere.
171 * Add enough to the size so that the result can be aligned.
172 */
173 if (mmap_write_lock_killable(mm))
174 return -EINTR;
175 vdso_base = get_unmapped_area(NULL, vdso_base,
176 (vdso_pages << PAGE_SHIFT) +
177 ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
178 0, 0);
179 if (IS_ERR_VALUE(vdso_base)) {
180 rc = vdso_base;
181 goto fail_mmapsem;
182 }
183
184 /* Add required alignment. */
185 vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
186
187 /*
188 * Put vDSO base into mm struct. We need to do this before calling
189 * install_special_mapping or the perf counter mmap tracking code
190 * will fail to recognise it as a vDSO (since arch_vma_name fails).
191 */
192 current->mm->context.vdso_base = vdso_base;
193
194 /*
195 * our vma flags don't have VM_WRITE so by default, the process isn't
196 * allowed to write those pages.
197 * gdb can break that with ptrace interface, and thus trigger COW on
198 * those pages but it's then your responsibility to never do that on
199 * the "data" page of the vDSO or you'll stop getting kernel updates
200 * and your nice userland gettimeofday will be totally dead.
201 * It's fine to use that for setting breakpoints in the vDSO code
202 * pages though.
203 */
204 rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
205 VM_READ|VM_EXEC|
206 VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
207 vdso_pagelist);
208 if (rc) {
209 current->mm->context.vdso_base = 0;
210 goto fail_mmapsem;
211 }
212
213 mmap_write_unlock(mm);
214 return 0;
215
216 fail_mmapsem:
217 mmap_write_unlock(mm);
218 return rc;
219 }
220
arch_vma_name(struct vm_area_struct * vma)221 const char *arch_vma_name(struct vm_area_struct *vma)
222 {
223 if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
224 return "[vdso]";
225 return NULL;
226 }
227
228
229
230 #ifdef CONFIG_VDSO32
find_section32(Elf32_Ehdr * ehdr,const char * secname,unsigned long * size)231 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
232 unsigned long *size)
233 {
234 Elf32_Shdr *sechdrs;
235 unsigned int i;
236 char *secnames;
237
238 /* Grab section headers and strings so we can tell who is who */
239 sechdrs = (void *)ehdr + ehdr->e_shoff;
240 secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
241
242 /* Find the section they want */
243 for (i = 1; i < ehdr->e_shnum; i++) {
244 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
245 if (size)
246 *size = sechdrs[i].sh_size;
247 return (void *)ehdr + sechdrs[i].sh_offset;
248 }
249 }
250 *size = 0;
251 return NULL;
252 }
253
find_symbol32(struct lib32_elfinfo * lib,const char * symname)254 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
255 const char *symname)
256 {
257 unsigned int i;
258 char name[MAX_SYMNAME], *c;
259
260 for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
261 if (lib->dynsym[i].st_name == 0)
262 continue;
263 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
264 MAX_SYMNAME);
265 c = strchr(name, '@');
266 if (c)
267 *c = 0;
268 if (strcmp(symname, name) == 0)
269 return &lib->dynsym[i];
270 }
271 return NULL;
272 }
273
274 /* Note that we assume the section is .text and the symbol is relative to
275 * the library base
276 */
find_function32(struct lib32_elfinfo * lib,const char * symname)277 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
278 const char *symname)
279 {
280 Elf32_Sym *sym = find_symbol32(lib, symname);
281
282 if (sym == NULL) {
283 printk(KERN_WARNING "vDSO32: function %s not found !\n",
284 symname);
285 return 0;
286 }
287 return sym->st_value - VDSO32_LBASE;
288 }
289
vdso_do_func_patch32(struct lib32_elfinfo * v32,struct lib64_elfinfo * v64,const char * orig,const char * fix)290 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
291 struct lib64_elfinfo *v64,
292 const char *orig, const char *fix)
293 {
294 Elf32_Sym *sym32_gen, *sym32_fix;
295
296 sym32_gen = find_symbol32(v32, orig);
297 if (sym32_gen == NULL) {
298 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
299 return -1;
300 }
301 if (fix == NULL) {
302 sym32_gen->st_name = 0;
303 return 0;
304 }
305 sym32_fix = find_symbol32(v32, fix);
306 if (sym32_fix == NULL) {
307 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
308 return -1;
309 }
310 sym32_gen->st_value = sym32_fix->st_value;
311 sym32_gen->st_size = sym32_fix->st_size;
312 sym32_gen->st_info = sym32_fix->st_info;
313 sym32_gen->st_other = sym32_fix->st_other;
314 sym32_gen->st_shndx = sym32_fix->st_shndx;
315
316 return 0;
317 }
318 #else /* !CONFIG_VDSO32 */
find_function32(struct lib32_elfinfo * lib,const char * symname)319 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
320 const char *symname)
321 {
322 return 0;
323 }
324
vdso_do_func_patch32(struct lib32_elfinfo * v32,struct lib64_elfinfo * v64,const char * orig,const char * fix)325 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
326 struct lib64_elfinfo *v64,
327 const char *orig, const char *fix)
328 {
329 return 0;
330 }
331 #endif /* CONFIG_VDSO32 */
332
333
334 #ifdef CONFIG_PPC64
335
find_section64(Elf64_Ehdr * ehdr,const char * secname,unsigned long * size)336 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
337 unsigned long *size)
338 {
339 Elf64_Shdr *sechdrs;
340 unsigned int i;
341 char *secnames;
342
343 /* Grab section headers and strings so we can tell who is who */
344 sechdrs = (void *)ehdr + ehdr->e_shoff;
345 secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
346
347 /* Find the section they want */
348 for (i = 1; i < ehdr->e_shnum; i++) {
349 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
350 if (size)
351 *size = sechdrs[i].sh_size;
352 return (void *)ehdr + sechdrs[i].sh_offset;
353 }
354 }
355 if (size)
356 *size = 0;
357 return NULL;
358 }
359
find_symbol64(struct lib64_elfinfo * lib,const char * symname)360 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
361 const char *symname)
362 {
363 unsigned int i;
364 char name[MAX_SYMNAME], *c;
365
366 for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
367 if (lib->dynsym[i].st_name == 0)
368 continue;
369 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
370 MAX_SYMNAME);
371 c = strchr(name, '@');
372 if (c)
373 *c = 0;
374 if (strcmp(symname, name) == 0)
375 return &lib->dynsym[i];
376 }
377 return NULL;
378 }
379
380 /* Note that we assume the section is .text and the symbol is relative to
381 * the library base
382 */
find_function64(struct lib64_elfinfo * lib,const char * symname)383 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
384 const char *symname)
385 {
386 Elf64_Sym *sym = find_symbol64(lib, symname);
387
388 if (sym == NULL) {
389 printk(KERN_WARNING "vDSO64: function %s not found !\n",
390 symname);
391 return 0;
392 }
393 return sym->st_value - VDSO64_LBASE;
394 }
395
vdso_do_func_patch64(struct lib32_elfinfo * v32,struct lib64_elfinfo * v64,const char * orig,const char * fix)396 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
397 struct lib64_elfinfo *v64,
398 const char *orig, const char *fix)
399 {
400 Elf64_Sym *sym64_gen, *sym64_fix;
401
402 sym64_gen = find_symbol64(v64, orig);
403 if (sym64_gen == NULL) {
404 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
405 return -1;
406 }
407 if (fix == NULL) {
408 sym64_gen->st_name = 0;
409 return 0;
410 }
411 sym64_fix = find_symbol64(v64, fix);
412 if (sym64_fix == NULL) {
413 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
414 return -1;
415 }
416 sym64_gen->st_value = sym64_fix->st_value;
417 sym64_gen->st_size = sym64_fix->st_size;
418 sym64_gen->st_info = sym64_fix->st_info;
419 sym64_gen->st_other = sym64_fix->st_other;
420 sym64_gen->st_shndx = sym64_fix->st_shndx;
421
422 return 0;
423 }
424
425 #endif /* CONFIG_PPC64 */
426
427
vdso_do_find_sections(struct lib32_elfinfo * v32,struct lib64_elfinfo * v64)428 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
429 struct lib64_elfinfo *v64)
430 {
431 void *sect;
432
433 /*
434 * Locate symbol tables & text section
435 */
436
437 #ifdef CONFIG_VDSO32
438 v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
439 v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
440 if (v32->dynsym == NULL || v32->dynstr == NULL) {
441 printk(KERN_ERR "vDSO32: required symbol section not found\n");
442 return -1;
443 }
444 sect = find_section32(v32->hdr, ".text", NULL);
445 if (sect == NULL) {
446 printk(KERN_ERR "vDSO32: the .text section was not found\n");
447 return -1;
448 }
449 v32->text = sect - vdso32_kbase;
450 #endif
451
452 #ifdef CONFIG_PPC64
453 v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
454 v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
455 if (v64->dynsym == NULL || v64->dynstr == NULL) {
456 printk(KERN_ERR "vDSO64: required symbol section not found\n");
457 return -1;
458 }
459 sect = find_section64(v64->hdr, ".text", NULL);
460 if (sect == NULL) {
461 printk(KERN_ERR "vDSO64: the .text section was not found\n");
462 return -1;
463 }
464 v64->text = sect - vdso64_kbase;
465 #endif /* CONFIG_PPC64 */
466
467 return 0;
468 }
469
vdso_setup_trampolines(struct lib32_elfinfo * v32,struct lib64_elfinfo * v64)470 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
471 struct lib64_elfinfo *v64)
472 {
473 /*
474 * Find signal trampolines
475 */
476
477 #ifdef CONFIG_PPC64
478 vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
479 #endif
480 vdso32_sigtramp = find_function32(v32, "__kernel_sigtramp32");
481 vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
482 }
483
vdso_fixup_datapage(struct lib32_elfinfo * v32,struct lib64_elfinfo * v64)484 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
485 struct lib64_elfinfo *v64)
486 {
487 #ifdef CONFIG_VDSO32
488 Elf32_Sym *sym32;
489 #endif
490 #ifdef CONFIG_PPC64
491 Elf64_Sym *sym64;
492
493 sym64 = find_symbol64(v64, "__kernel_datapage_offset");
494 if (sym64 == NULL) {
495 printk(KERN_ERR "vDSO64: Can't find symbol "
496 "__kernel_datapage_offset !\n");
497 return -1;
498 }
499 *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
500 (vdso64_pages << PAGE_SHIFT) -
501 (sym64->st_value - VDSO64_LBASE);
502 #endif /* CONFIG_PPC64 */
503
504 #ifdef CONFIG_VDSO32
505 sym32 = find_symbol32(v32, "__kernel_datapage_offset");
506 if (sym32 == NULL) {
507 printk(KERN_ERR "vDSO32: Can't find symbol "
508 "__kernel_datapage_offset !\n");
509 return -1;
510 }
511 *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
512 (vdso32_pages << PAGE_SHIFT) -
513 (sym32->st_value - VDSO32_LBASE);
514 #endif
515
516 return 0;
517 }
518
519
vdso_fixup_features(struct lib32_elfinfo * v32,struct lib64_elfinfo * v64)520 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
521 struct lib64_elfinfo *v64)
522 {
523 unsigned long size;
524 void *start;
525
526 #ifdef CONFIG_PPC64
527 start = find_section64(v64->hdr, "__ftr_fixup", &size);
528 if (start)
529 do_feature_fixups(cur_cpu_spec->cpu_features,
530 start, start + size);
531
532 start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);
533 if (start)
534 do_feature_fixups(cur_cpu_spec->mmu_features,
535 start, start + size);
536
537 start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);
538 if (start)
539 do_feature_fixups(powerpc_firmware_features,
540 start, start + size);
541
542 start = find_section64(v64->hdr, "__lwsync_fixup", &size);
543 if (start)
544 do_lwsync_fixups(cur_cpu_spec->cpu_features,
545 start, start + size);
546 #endif /* CONFIG_PPC64 */
547
548 #ifdef CONFIG_VDSO32
549 start = find_section32(v32->hdr, "__ftr_fixup", &size);
550 if (start)
551 do_feature_fixups(cur_cpu_spec->cpu_features,
552 start, start + size);
553
554 start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);
555 if (start)
556 do_feature_fixups(cur_cpu_spec->mmu_features,
557 start, start + size);
558
559 #ifdef CONFIG_PPC64
560 start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);
561 if (start)
562 do_feature_fixups(powerpc_firmware_features,
563 start, start + size);
564 #endif /* CONFIG_PPC64 */
565
566 start = find_section32(v32->hdr, "__lwsync_fixup", &size);
567 if (start)
568 do_lwsync_fixups(cur_cpu_spec->cpu_features,
569 start, start + size);
570 #endif
571
572 return 0;
573 }
574
vdso_fixup_alt_funcs(struct lib32_elfinfo * v32,struct lib64_elfinfo * v64)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
vdso_setup(void)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_features(&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 */
vdso_setup_syscall_map(void)638 static void __init vdso_setup_syscall_map(void)
639 {
640 unsigned int i;
641 extern unsigned long *sys_call_table;
642 #ifdef CONFIG_PPC64
643 extern unsigned long *compat_sys_call_table;
644 #endif
645 extern unsigned long sys_ni_syscall;
646
647
648 for (i = 0; i < NR_syscalls; i++) {
649 #ifdef CONFIG_PPC64
650 if (sys_call_table[i] != sys_ni_syscall)
651 vdso_data->syscall_map_64[i >> 5] |=
652 0x80000000UL >> (i & 0x1f);
653 if (IS_ENABLED(CONFIG_COMPAT) &&
654 compat_sys_call_table[i] != sys_ni_syscall)
655 vdso_data->syscall_map_32[i >> 5] |=
656 0x80000000UL >> (i & 0x1f);
657 #else /* CONFIG_PPC64 */
658 if (sys_call_table[i] != sys_ni_syscall)
659 vdso_data->syscall_map_32[i >> 5] |=
660 0x80000000UL >> (i & 0x1f);
661 #endif /* CONFIG_PPC64 */
662 }
663 }
664
665 #ifdef CONFIG_PPC64
vdso_getcpu_init(void)666 int vdso_getcpu_init(void)
667 {
668 unsigned long cpu, node, val;
669
670 /*
671 * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
672 * in the next 16 bits. The VDSO uses this to implement getcpu().
673 */
674 cpu = get_cpu();
675 WARN_ON_ONCE(cpu > 0xffff);
676
677 node = cpu_to_node(cpu);
678 WARN_ON_ONCE(node > 0xffff);
679
680 val = (cpu & 0xffff) | ((node & 0xffff) << 16);
681 mtspr(SPRN_SPRG_VDSO_WRITE, val);
682 get_paca()->sprg_vdso = val;
683
684 put_cpu();
685
686 return 0;
687 }
688 /* We need to call this before SMP init */
689 early_initcall(vdso_getcpu_init);
690 #endif
691
vdso_init(void)692 static int __init vdso_init(void)
693 {
694 int i;
695
696 #ifdef CONFIG_PPC64
697 /*
698 * Fill up the "systemcfg" stuff for backward compatibility
699 */
700 strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
701 vdso_data->version.major = SYSTEMCFG_MAJOR;
702 vdso_data->version.minor = SYSTEMCFG_MINOR;
703 vdso_data->processor = mfspr(SPRN_PVR);
704 /*
705 * Fake the old platform number for pSeries and add
706 * in LPAR bit if necessary
707 */
708 vdso_data->platform = 0x100;
709 if (firmware_has_feature(FW_FEATURE_LPAR))
710 vdso_data->platform |= 1;
711 vdso_data->physicalMemorySize = memblock_phys_mem_size();
712 vdso_data->dcache_size = ppc64_caches.l1d.size;
713 vdso_data->dcache_line_size = ppc64_caches.l1d.line_size;
714 vdso_data->icache_size = ppc64_caches.l1i.size;
715 vdso_data->icache_line_size = ppc64_caches.l1i.line_size;
716 vdso_data->dcache_block_size = ppc64_caches.l1d.block_size;
717 vdso_data->icache_block_size = ppc64_caches.l1i.block_size;
718 vdso_data->dcache_log_block_size = ppc64_caches.l1d.log_block_size;
719 vdso_data->icache_log_block_size = ppc64_caches.l1i.log_block_size;
720
721 /*
722 * Calculate the size of the 64 bits vDSO
723 */
724 vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
725 DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
726 #endif /* CONFIG_PPC64 */
727
728
729 #ifdef CONFIG_VDSO32
730 vdso32_kbase = &vdso32_start;
731
732 /*
733 * Calculate the size of the 32 bits vDSO
734 */
735 vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
736 DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
737 #endif
738
739
740 /*
741 * Setup the syscall map in the vDOS
742 */
743 vdso_setup_syscall_map();
744
745 /*
746 * Initialize the vDSO images in memory, that is do necessary
747 * fixups of vDSO symbols, locate trampolines, etc...
748 */
749 if (vdso_setup()) {
750 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
751 vdso32_pages = 0;
752 #ifdef CONFIG_PPC64
753 vdso64_pages = 0;
754 #endif
755 return 0;
756 }
757
758 #ifdef CONFIG_VDSO32
759 /* Make sure pages are in the correct state */
760 vdso32_pagelist = kcalloc(vdso32_pages + 2, sizeof(struct page *),
761 GFP_KERNEL);
762 BUG_ON(vdso32_pagelist == NULL);
763 for (i = 0; i < vdso32_pages; i++) {
764 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
765 get_page(pg);
766 vdso32_pagelist[i] = pg;
767 }
768 vdso32_pagelist[i++] = virt_to_page(vdso_data);
769 vdso32_pagelist[i] = NULL;
770 #endif
771
772 #ifdef CONFIG_PPC64
773 vdso64_pagelist = kcalloc(vdso64_pages + 2, sizeof(struct page *),
774 GFP_KERNEL);
775 BUG_ON(vdso64_pagelist == NULL);
776 for (i = 0; i < vdso64_pages; i++) {
777 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
778 get_page(pg);
779 vdso64_pagelist[i] = pg;
780 }
781 vdso64_pagelist[i++] = virt_to_page(vdso_data);
782 vdso64_pagelist[i] = NULL;
783 #endif /* CONFIG_PPC64 */
784
785 get_page(virt_to_page(vdso_data));
786
787 smp_wmb();
788 vdso_ready = 1;
789
790 return 0;
791 }
792 arch_initcall(vdso_init);
793