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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
47static unsigned int vdso32_pages;
48static void *vdso32_kbase;
49static struct page **vdso32_pagelist;
50unsigned long vdso32_sigtramp;
51unsigned long vdso32_rt_sigtramp;
52
53#ifdef CONFIG_VDSO32
54extern char vdso32_start, vdso32_end;
55#endif
56
57#ifdef CONFIG_PPC64
58extern char vdso64_start, vdso64_end;
59static void *vdso64_kbase = &vdso64_start;
60static unsigned int vdso64_pages;
61static struct page **vdso64_pagelist;
62unsigned long vdso64_rt_sigtramp;
63#endif /* CONFIG_PPC64 */
64
65static 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 */
72static union {
73 struct vdso_data data;
74 u8 page[PAGE_SIZE];
75} vdso_data_store __page_aligned_data;
76struct vdso_data *vdso_data = &vdso_data_store.data;
77
78/* Format of the patch table */
79struct 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 */
91static 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 */
102struct 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
111struct 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 */
125int 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
221const 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
231static 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
254static 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 */
277static 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
290static 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 */
319static unsigned long __init find_function32(struct lib32_elfinfo *lib,
320 const char *symname)
321{
322 return 0;
323}
324
325static 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
336static 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
360static 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 */
383static 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
396static 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
428static __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
470static __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
484static __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
520static __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
575static __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
608static __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 */
638static 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
666int 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 */
689early_initcall(vdso_getcpu_init);
690#endif
691
692static 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}
792arch_initcall(vdso_init);
1
2/*
3 * Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
4 * <benh@kernel.crashing.org>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/errno.h>
13#include <linux/sched.h>
14#include <linux/kernel.h>
15#include <linux/mm.h>
16#include <linux/smp.h>
17#include <linux/stddef.h>
18#include <linux/unistd.h>
19#include <linux/slab.h>
20#include <linux/user.h>
21#include <linux/elf.h>
22#include <linux/security.h>
23#include <linux/memblock.h>
24
25#include <asm/pgtable.h>
26#include <asm/processor.h>
27#include <asm/mmu.h>
28#include <asm/mmu_context.h>
29#include <asm/prom.h>
30#include <asm/machdep.h>
31#include <asm/cputable.h>
32#include <asm/sections.h>
33#include <asm/firmware.h>
34#include <asm/vdso.h>
35#include <asm/vdso_datapage.h>
36#include <asm/setup.h>
37
38#undef DEBUG
39
40#ifdef DEBUG
41#define DBG(fmt...) printk(fmt)
42#else
43#define DBG(fmt...)
44#endif
45
46/* Max supported size for symbol names */
47#define MAX_SYMNAME 64
48
49/* The alignment of the vDSO */
50#define VDSO_ALIGNMENT (1 << 16)
51
52static unsigned int vdso32_pages;
53static void *vdso32_kbase;
54static struct page **vdso32_pagelist;
55unsigned long vdso32_sigtramp;
56unsigned long vdso32_rt_sigtramp;
57
58#ifdef CONFIG_VDSO32
59extern char vdso32_start, vdso32_end;
60#endif
61
62#ifdef CONFIG_PPC64
63extern char vdso64_start, vdso64_end;
64static void *vdso64_kbase = &vdso64_start;
65static unsigned int vdso64_pages;
66static struct page **vdso64_pagelist;
67unsigned long vdso64_rt_sigtramp;
68#endif /* CONFIG_PPC64 */
69
70static int vdso_ready;
71
72/*
73 * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
74 * Once the early boot kernel code no longer needs to muck around
75 * with it, it will become dynamically allocated
76 */
77static union {
78 struct vdso_data data;
79 u8 page[PAGE_SIZE];
80} vdso_data_store __page_aligned_data;
81struct vdso_data *vdso_data = &vdso_data_store.data;
82
83/* Format of the patch table */
84struct vdso_patch_def
85{
86 unsigned long ftr_mask, ftr_value;
87 const char *gen_name;
88 const char *fix_name;
89};
90
91/* Table of functions to patch based on the CPU type/revision
92 *
93 * Currently, we only change sync_dicache to do nothing on processors
94 * with a coherent icache
95 */
96static struct vdso_patch_def vdso_patches[] = {
97 {
98 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
99 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
100 },
101 {
102 CPU_FTR_USE_TB, 0,
103 "__kernel_gettimeofday", NULL
104 },
105 {
106 CPU_FTR_USE_TB, 0,
107 "__kernel_clock_gettime", NULL
108 },
109 {
110 CPU_FTR_USE_TB, 0,
111 "__kernel_clock_getres", NULL
112 },
113 {
114 CPU_FTR_USE_TB, 0,
115 "__kernel_get_tbfreq", NULL
116 },
117 {
118 CPU_FTR_USE_TB, 0,
119 "__kernel_time", NULL
120 },
121};
122
123/*
124 * Some infos carried around for each of them during parsing at
125 * boot time.
126 */
127struct lib32_elfinfo
128{
129 Elf32_Ehdr *hdr; /* ptr to ELF */
130 Elf32_Sym *dynsym; /* ptr to .dynsym section */
131 unsigned long dynsymsize; /* size of .dynsym section */
132 char *dynstr; /* ptr to .dynstr section */
133 unsigned long text; /* offset of .text section in .so */
134};
135
136struct lib64_elfinfo
137{
138 Elf64_Ehdr *hdr;
139 Elf64_Sym *dynsym;
140 unsigned long dynsymsize;
141 char *dynstr;
142 unsigned long text;
143};
144
145
146/*
147 * This is called from binfmt_elf, we create the special vma for the
148 * vDSO and insert it into the mm struct tree
149 */
150int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
151{
152 struct mm_struct *mm = current->mm;
153 struct page **vdso_pagelist;
154 unsigned long vdso_pages;
155 unsigned long vdso_base;
156 int rc;
157
158 if (!vdso_ready)
159 return 0;
160
161#ifdef CONFIG_PPC64
162 if (is_32bit_task()) {
163 vdso_pagelist = vdso32_pagelist;
164 vdso_pages = vdso32_pages;
165 vdso_base = VDSO32_MBASE;
166 } else {
167 vdso_pagelist = vdso64_pagelist;
168 vdso_pages = vdso64_pages;
169 /*
170 * On 64bit we don't have a preferred map address. This
171 * allows get_unmapped_area to find an area near other mmaps
172 * and most likely share a SLB entry.
173 */
174 vdso_base = 0;
175 }
176#else
177 vdso_pagelist = vdso32_pagelist;
178 vdso_pages = vdso32_pages;
179 vdso_base = VDSO32_MBASE;
180#endif
181
182 current->mm->context.vdso_base = 0;
183
184 /* vDSO has a problem and was disabled, just don't "enable" it for the
185 * process
186 */
187 if (vdso_pages == 0)
188 return 0;
189 /* Add a page to the vdso size for the data page */
190 vdso_pages ++;
191
192 /*
193 * pick a base address for the vDSO in process space. We try to put it
194 * at vdso_base which is the "natural" base for it, but we might fail
195 * and end up putting it elsewhere.
196 * Add enough to the size so that the result can be aligned.
197 */
198 down_write(&mm->mmap_sem);
199 vdso_base = get_unmapped_area(NULL, vdso_base,
200 (vdso_pages << PAGE_SHIFT) +
201 ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
202 0, 0);
203 if (IS_ERR_VALUE(vdso_base)) {
204 rc = vdso_base;
205 goto fail_mmapsem;
206 }
207
208 /* Add required alignment. */
209 vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
210
211 /*
212 * Put vDSO base into mm struct. We need to do this before calling
213 * install_special_mapping or the perf counter mmap tracking code
214 * will fail to recognise it as a vDSO (since arch_vma_name fails).
215 */
216 current->mm->context.vdso_base = vdso_base;
217
218 /*
219 * our vma flags don't have VM_WRITE so by default, the process isn't
220 * allowed to write those pages.
221 * gdb can break that with ptrace interface, and thus trigger COW on
222 * those pages but it's then your responsibility to never do that on
223 * the "data" page of the vDSO or you'll stop getting kernel updates
224 * and your nice userland gettimeofday will be totally dead.
225 * It's fine to use that for setting breakpoints in the vDSO code
226 * pages though.
227 */
228 rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
229 VM_READ|VM_EXEC|
230 VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
231 vdso_pagelist);
232 if (rc) {
233 current->mm->context.vdso_base = 0;
234 goto fail_mmapsem;
235 }
236
237 up_write(&mm->mmap_sem);
238 return 0;
239
240 fail_mmapsem:
241 up_write(&mm->mmap_sem);
242 return rc;
243}
244
245const char *arch_vma_name(struct vm_area_struct *vma)
246{
247 if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
248 return "[vdso]";
249 return NULL;
250}
251
252
253
254#ifdef CONFIG_VDSO32
255static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
256 unsigned long *size)
257{
258 Elf32_Shdr *sechdrs;
259 unsigned int i;
260 char *secnames;
261
262 /* Grab section headers and strings so we can tell who is who */
263 sechdrs = (void *)ehdr + ehdr->e_shoff;
264 secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
265
266 /* Find the section they want */
267 for (i = 1; i < ehdr->e_shnum; i++) {
268 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
269 if (size)
270 *size = sechdrs[i].sh_size;
271 return (void *)ehdr + sechdrs[i].sh_offset;
272 }
273 }
274 *size = 0;
275 return NULL;
276}
277
278static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
279 const char *symname)
280{
281 unsigned int i;
282 char name[MAX_SYMNAME], *c;
283
284 for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
285 if (lib->dynsym[i].st_name == 0)
286 continue;
287 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
288 MAX_SYMNAME);
289 c = strchr(name, '@');
290 if (c)
291 *c = 0;
292 if (strcmp(symname, name) == 0)
293 return &lib->dynsym[i];
294 }
295 return NULL;
296}
297
298/* Note that we assume the section is .text and the symbol is relative to
299 * the library base
300 */
301static unsigned long __init find_function32(struct lib32_elfinfo *lib,
302 const char *symname)
303{
304 Elf32_Sym *sym = find_symbol32(lib, symname);
305
306 if (sym == NULL) {
307 printk(KERN_WARNING "vDSO32: function %s not found !\n",
308 symname);
309 return 0;
310 }
311 return sym->st_value - VDSO32_LBASE;
312}
313
314static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
315 struct lib64_elfinfo *v64,
316 const char *orig, const char *fix)
317{
318 Elf32_Sym *sym32_gen, *sym32_fix;
319
320 sym32_gen = find_symbol32(v32, orig);
321 if (sym32_gen == NULL) {
322 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
323 return -1;
324 }
325 if (fix == NULL) {
326 sym32_gen->st_name = 0;
327 return 0;
328 }
329 sym32_fix = find_symbol32(v32, fix);
330 if (sym32_fix == NULL) {
331 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
332 return -1;
333 }
334 sym32_gen->st_value = sym32_fix->st_value;
335 sym32_gen->st_size = sym32_fix->st_size;
336 sym32_gen->st_info = sym32_fix->st_info;
337 sym32_gen->st_other = sym32_fix->st_other;
338 sym32_gen->st_shndx = sym32_fix->st_shndx;
339
340 return 0;
341}
342#else /* !CONFIG_VDSO32 */
343static unsigned long __init find_function32(struct lib32_elfinfo *lib,
344 const char *symname)
345{
346 return 0;
347}
348
349static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
350 struct lib64_elfinfo *v64,
351 const char *orig, const char *fix)
352{
353 return 0;
354}
355#endif /* CONFIG_VDSO32 */
356
357
358#ifdef CONFIG_PPC64
359
360static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
361 unsigned long *size)
362{
363 Elf64_Shdr *sechdrs;
364 unsigned int i;
365 char *secnames;
366
367 /* Grab section headers and strings so we can tell who is who */
368 sechdrs = (void *)ehdr + ehdr->e_shoff;
369 secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
370
371 /* Find the section they want */
372 for (i = 1; i < ehdr->e_shnum; i++) {
373 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
374 if (size)
375 *size = sechdrs[i].sh_size;
376 return (void *)ehdr + sechdrs[i].sh_offset;
377 }
378 }
379 if (size)
380 *size = 0;
381 return NULL;
382}
383
384static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
385 const char *symname)
386{
387 unsigned int i;
388 char name[MAX_SYMNAME], *c;
389
390 for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
391 if (lib->dynsym[i].st_name == 0)
392 continue;
393 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
394 MAX_SYMNAME);
395 c = strchr(name, '@');
396 if (c)
397 *c = 0;
398 if (strcmp(symname, name) == 0)
399 return &lib->dynsym[i];
400 }
401 return NULL;
402}
403
404/* Note that we assume the section is .text and the symbol is relative to
405 * the library base
406 */
407static unsigned long __init find_function64(struct lib64_elfinfo *lib,
408 const char *symname)
409{
410 Elf64_Sym *sym = find_symbol64(lib, symname);
411
412 if (sym == NULL) {
413 printk(KERN_WARNING "vDSO64: function %s not found !\n",
414 symname);
415 return 0;
416 }
417#ifdef VDS64_HAS_DESCRIPTORS
418 return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
419 VDSO64_LBASE;
420#else
421 return sym->st_value - VDSO64_LBASE;
422#endif
423}
424
425static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
426 struct lib64_elfinfo *v64,
427 const char *orig, const char *fix)
428{
429 Elf64_Sym *sym64_gen, *sym64_fix;
430
431 sym64_gen = find_symbol64(v64, orig);
432 if (sym64_gen == NULL) {
433 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
434 return -1;
435 }
436 if (fix == NULL) {
437 sym64_gen->st_name = 0;
438 return 0;
439 }
440 sym64_fix = find_symbol64(v64, fix);
441 if (sym64_fix == NULL) {
442 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
443 return -1;
444 }
445 sym64_gen->st_value = sym64_fix->st_value;
446 sym64_gen->st_size = sym64_fix->st_size;
447 sym64_gen->st_info = sym64_fix->st_info;
448 sym64_gen->st_other = sym64_fix->st_other;
449 sym64_gen->st_shndx = sym64_fix->st_shndx;
450
451 return 0;
452}
453
454#endif /* CONFIG_PPC64 */
455
456
457static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
458 struct lib64_elfinfo *v64)
459{
460 void *sect;
461
462 /*
463 * Locate symbol tables & text section
464 */
465
466#ifdef CONFIG_VDSO32
467 v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
468 v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
469 if (v32->dynsym == NULL || v32->dynstr == NULL) {
470 printk(KERN_ERR "vDSO32: required symbol section not found\n");
471 return -1;
472 }
473 sect = find_section32(v32->hdr, ".text", NULL);
474 if (sect == NULL) {
475 printk(KERN_ERR "vDSO32: the .text section was not found\n");
476 return -1;
477 }
478 v32->text = sect - vdso32_kbase;
479#endif
480
481#ifdef CONFIG_PPC64
482 v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
483 v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
484 if (v64->dynsym == NULL || v64->dynstr == NULL) {
485 printk(KERN_ERR "vDSO64: required symbol section not found\n");
486 return -1;
487 }
488 sect = find_section64(v64->hdr, ".text", NULL);
489 if (sect == NULL) {
490 printk(KERN_ERR "vDSO64: the .text section was not found\n");
491 return -1;
492 }
493 v64->text = sect - vdso64_kbase;
494#endif /* CONFIG_PPC64 */
495
496 return 0;
497}
498
499static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
500 struct lib64_elfinfo *v64)
501{
502 /*
503 * Find signal trampolines
504 */
505
506#ifdef CONFIG_PPC64
507 vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
508#endif
509 vdso32_sigtramp = find_function32(v32, "__kernel_sigtramp32");
510 vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
511}
512
513static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
514 struct lib64_elfinfo *v64)
515{
516#ifdef CONFIG_VDSO32
517 Elf32_Sym *sym32;
518#endif
519#ifdef CONFIG_PPC64
520 Elf64_Sym *sym64;
521
522 sym64 = find_symbol64(v64, "__kernel_datapage_offset");
523 if (sym64 == NULL) {
524 printk(KERN_ERR "vDSO64: Can't find symbol "
525 "__kernel_datapage_offset !\n");
526 return -1;
527 }
528 *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
529 (vdso64_pages << PAGE_SHIFT) -
530 (sym64->st_value - VDSO64_LBASE);
531#endif /* CONFIG_PPC64 */
532
533#ifdef CONFIG_VDSO32
534 sym32 = find_symbol32(v32, "__kernel_datapage_offset");
535 if (sym32 == NULL) {
536 printk(KERN_ERR "vDSO32: Can't find symbol "
537 "__kernel_datapage_offset !\n");
538 return -1;
539 }
540 *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
541 (vdso32_pages << PAGE_SHIFT) -
542 (sym32->st_value - VDSO32_LBASE);
543#endif
544
545 return 0;
546}
547
548
549static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
550 struct lib64_elfinfo *v64)
551{
552 unsigned long size;
553 void *start;
554
555#ifdef CONFIG_PPC64
556 start = find_section64(v64->hdr, "__ftr_fixup", &size);
557 if (start)
558 do_feature_fixups(cur_cpu_spec->cpu_features,
559 start, start + size);
560
561 start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);
562 if (start)
563 do_feature_fixups(cur_cpu_spec->mmu_features,
564 start, start + size);
565
566 start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);
567 if (start)
568 do_feature_fixups(powerpc_firmware_features,
569 start, start + size);
570
571 start = find_section64(v64->hdr, "__lwsync_fixup", &size);
572 if (start)
573 do_lwsync_fixups(cur_cpu_spec->cpu_features,
574 start, start + size);
575#endif /* CONFIG_PPC64 */
576
577#ifdef CONFIG_VDSO32
578 start = find_section32(v32->hdr, "__ftr_fixup", &size);
579 if (start)
580 do_feature_fixups(cur_cpu_spec->cpu_features,
581 start, start + size);
582
583 start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);
584 if (start)
585 do_feature_fixups(cur_cpu_spec->mmu_features,
586 start, start + size);
587
588#ifdef CONFIG_PPC64
589 start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);
590 if (start)
591 do_feature_fixups(powerpc_firmware_features,
592 start, start + size);
593#endif /* CONFIG_PPC64 */
594
595 start = find_section32(v32->hdr, "__lwsync_fixup", &size);
596 if (start)
597 do_lwsync_fixups(cur_cpu_spec->cpu_features,
598 start, start + size);
599#endif
600
601 return 0;
602}
603
604static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
605 struct lib64_elfinfo *v64)
606{
607 int i;
608
609 for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
610 struct vdso_patch_def *patch = &vdso_patches[i];
611 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
612 == patch->ftr_value;
613 if (!match)
614 continue;
615
616 DBG("replacing %s with %s...\n", patch->gen_name,
617 patch->fix_name ? "NONE" : patch->fix_name);
618
619 /*
620 * Patch the 32 bits and 64 bits symbols. Note that we do not
621 * patch the "." symbol on 64 bits.
622 * It would be easy to do, but doesn't seem to be necessary,
623 * patching the OPD symbol is enough.
624 */
625 vdso_do_func_patch32(v32, v64, patch->gen_name,
626 patch->fix_name);
627#ifdef CONFIG_PPC64
628 vdso_do_func_patch64(v32, v64, patch->gen_name,
629 patch->fix_name);
630#endif /* CONFIG_PPC64 */
631 }
632
633 return 0;
634}
635
636
637static __init int vdso_setup(void)
638{
639 struct lib32_elfinfo v32;
640 struct lib64_elfinfo v64;
641
642 v32.hdr = vdso32_kbase;
643#ifdef CONFIG_PPC64
644 v64.hdr = vdso64_kbase;
645#endif
646 if (vdso_do_find_sections(&v32, &v64))
647 return -1;
648
649 if (vdso_fixup_datapage(&v32, &v64))
650 return -1;
651
652 if (vdso_fixup_features(&v32, &v64))
653 return -1;
654
655 if (vdso_fixup_alt_funcs(&v32, &v64))
656 return -1;
657
658 vdso_setup_trampolines(&v32, &v64);
659
660 return 0;
661}
662
663/*
664 * Called from setup_arch to initialize the bitmap of available
665 * syscalls in the systemcfg page
666 */
667static void __init vdso_setup_syscall_map(void)
668{
669 unsigned int i;
670 extern unsigned long *sys_call_table;
671 extern unsigned long sys_ni_syscall;
672
673
674 for (i = 0; i < NR_syscalls; i++) {
675#ifdef CONFIG_PPC64
676 if (sys_call_table[i*2] != sys_ni_syscall)
677 vdso_data->syscall_map_64[i >> 5] |=
678 0x80000000UL >> (i & 0x1f);
679 if (sys_call_table[i*2+1] != sys_ni_syscall)
680 vdso_data->syscall_map_32[i >> 5] |=
681 0x80000000UL >> (i & 0x1f);
682#else /* CONFIG_PPC64 */
683 if (sys_call_table[i] != sys_ni_syscall)
684 vdso_data->syscall_map_32[i >> 5] |=
685 0x80000000UL >> (i & 0x1f);
686#endif /* CONFIG_PPC64 */
687 }
688}
689
690#ifdef CONFIG_PPC64
691int vdso_getcpu_init(void)
692{
693 unsigned long cpu, node, val;
694
695 /*
696 * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
697 * in the next 16 bits. The VDSO uses this to implement getcpu().
698 */
699 cpu = get_cpu();
700 WARN_ON_ONCE(cpu > 0xffff);
701
702 node = cpu_to_node(cpu);
703 WARN_ON_ONCE(node > 0xffff);
704
705 val = (cpu & 0xfff) | ((node & 0xffff) << 16);
706 mtspr(SPRN_SPRG_VDSO_WRITE, val);
707 get_paca()->sprg_vdso = val;
708
709 put_cpu();
710
711 return 0;
712}
713/* We need to call this before SMP init */
714early_initcall(vdso_getcpu_init);
715#endif
716
717static int __init vdso_init(void)
718{
719 int i;
720
721#ifdef CONFIG_PPC64
722 /*
723 * Fill up the "systemcfg" stuff for backward compatibility
724 */
725 strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
726 vdso_data->version.major = SYSTEMCFG_MAJOR;
727 vdso_data->version.minor = SYSTEMCFG_MINOR;
728 vdso_data->processor = mfspr(SPRN_PVR);
729 /*
730 * Fake the old platform number for pSeries and add
731 * in LPAR bit if necessary
732 */
733 vdso_data->platform = 0x100;
734 if (firmware_has_feature(FW_FEATURE_LPAR))
735 vdso_data->platform |= 1;
736 vdso_data->physicalMemorySize = memblock_phys_mem_size();
737 vdso_data->dcache_size = ppc64_caches.dsize;
738 vdso_data->dcache_line_size = ppc64_caches.dline_size;
739 vdso_data->icache_size = ppc64_caches.isize;
740 vdso_data->icache_line_size = ppc64_caches.iline_size;
741
742 /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
743 vdso_data->dcache_block_size = ppc64_caches.dline_size;
744 vdso_data->icache_block_size = ppc64_caches.iline_size;
745 vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
746 vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
747
748 /*
749 * Calculate the size of the 64 bits vDSO
750 */
751 vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
752 DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
753#else
754 vdso_data->dcache_block_size = L1_CACHE_BYTES;
755 vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
756 vdso_data->icache_block_size = L1_CACHE_BYTES;
757 vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
758#endif /* CONFIG_PPC64 */
759
760
761#ifdef CONFIG_VDSO32
762 vdso32_kbase = &vdso32_start;
763
764 /*
765 * Calculate the size of the 32 bits vDSO
766 */
767 vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
768 DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
769#endif
770
771
772 /*
773 * Setup the syscall map in the vDOS
774 */
775 vdso_setup_syscall_map();
776
777 /*
778 * Initialize the vDSO images in memory, that is do necessary
779 * fixups of vDSO symbols, locate trampolines, etc...
780 */
781 if (vdso_setup()) {
782 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
783 vdso32_pages = 0;
784#ifdef CONFIG_PPC64
785 vdso64_pages = 0;
786#endif
787 return 0;
788 }
789
790#ifdef CONFIG_VDSO32
791 /* Make sure pages are in the correct state */
792 vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
793 GFP_KERNEL);
794 BUG_ON(vdso32_pagelist == NULL);
795 for (i = 0; i < vdso32_pages; i++) {
796 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
797 ClearPageReserved(pg);
798 get_page(pg);
799 vdso32_pagelist[i] = pg;
800 }
801 vdso32_pagelist[i++] = virt_to_page(vdso_data);
802 vdso32_pagelist[i] = NULL;
803#endif
804
805#ifdef CONFIG_PPC64
806 vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
807 GFP_KERNEL);
808 BUG_ON(vdso64_pagelist == NULL);
809 for (i = 0; i < vdso64_pages; i++) {
810 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
811 ClearPageReserved(pg);
812 get_page(pg);
813 vdso64_pagelist[i] = pg;
814 }
815 vdso64_pagelist[i++] = virt_to_page(vdso_data);
816 vdso64_pagelist[i] = NULL;
817#endif /* CONFIG_PPC64 */
818
819 get_page(virt_to_page(vdso_data));
820
821 smp_wmb();
822 vdso_ready = 1;
823
824 return 0;
825}
826arch_initcall(vdso_init);