Loading...
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/cpu_has_feature.h>
26#include <asm/pgtable.h>
27#include <asm/processor.h>
28#include <asm/mmu.h>
29#include <asm/mmu_context.h>
30#include <asm/prom.h>
31#include <asm/machdep.h>
32#include <asm/cputable.h>
33#include <asm/sections.h>
34#include <asm/firmware.h>
35#include <asm/vdso.h>
36#include <asm/vdso_datapage.h>
37#include <asm/setup.h>
38
39#undef DEBUG
40
41#ifdef DEBUG
42#define DBG(fmt...) printk(fmt)
43#else
44#define DBG(fmt...)
45#endif
46
47/* Max supported size for symbol names */
48#define MAX_SYMNAME 64
49
50/* The alignment of the vDSO */
51#define VDSO_ALIGNMENT (1 << 16)
52
53static unsigned int vdso32_pages;
54static void *vdso32_kbase;
55static struct page **vdso32_pagelist;
56unsigned long vdso32_sigtramp;
57unsigned long vdso32_rt_sigtramp;
58
59#ifdef CONFIG_VDSO32
60extern char vdso32_start, vdso32_end;
61#endif
62
63#ifdef CONFIG_PPC64
64extern char vdso64_start, vdso64_end;
65static void *vdso64_kbase = &vdso64_start;
66static unsigned int vdso64_pages;
67static struct page **vdso64_pagelist;
68unsigned long vdso64_rt_sigtramp;
69#endif /* CONFIG_PPC64 */
70
71static int vdso_ready;
72
73/*
74 * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
75 * Once the early boot kernel code no longer needs to muck around
76 * with it, it will become dynamically allocated
77 */
78static union {
79 struct vdso_data data;
80 u8 page[PAGE_SIZE];
81} vdso_data_store __page_aligned_data;
82struct vdso_data *vdso_data = &vdso_data_store.data;
83
84/* Format of the patch table */
85struct vdso_patch_def
86{
87 unsigned long ftr_mask, ftr_value;
88 const char *gen_name;
89 const char *fix_name;
90};
91
92/* Table of functions to patch based on the CPU type/revision
93 *
94 * Currently, we only change sync_dicache to do nothing on processors
95 * with a coherent icache
96 */
97static struct vdso_patch_def vdso_patches[] = {
98 {
99 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
100 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
101 },
102 {
103 CPU_FTR_USE_TB, 0,
104 "__kernel_gettimeofday", NULL
105 },
106 {
107 CPU_FTR_USE_TB, 0,
108 "__kernel_clock_gettime", NULL
109 },
110 {
111 CPU_FTR_USE_TB, 0,
112 "__kernel_clock_getres", NULL
113 },
114 {
115 CPU_FTR_USE_TB, 0,
116 "__kernel_get_tbfreq", NULL
117 },
118 {
119 CPU_FTR_USE_TB, 0,
120 "__kernel_time", NULL
121 },
122};
123
124/*
125 * Some infos carried around for each of them during parsing at
126 * boot time.
127 */
128struct lib32_elfinfo
129{
130 Elf32_Ehdr *hdr; /* ptr to ELF */
131 Elf32_Sym *dynsym; /* ptr to .dynsym section */
132 unsigned long dynsymsize; /* size of .dynsym section */
133 char *dynstr; /* ptr to .dynstr section */
134 unsigned long text; /* offset of .text section in .so */
135};
136
137struct lib64_elfinfo
138{
139 Elf64_Ehdr *hdr;
140 Elf64_Sym *dynsym;
141 unsigned long dynsymsize;
142 char *dynstr;
143 unsigned long text;
144};
145
146
147/*
148 * This is called from binfmt_elf, we create the special vma for the
149 * vDSO and insert it into the mm struct tree
150 */
151int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
152{
153 struct mm_struct *mm = current->mm;
154 struct page **vdso_pagelist;
155 unsigned long vdso_pages;
156 unsigned long vdso_base;
157 int rc;
158
159 if (!vdso_ready)
160 return 0;
161
162#ifdef CONFIG_PPC64
163 if (is_32bit_task()) {
164 vdso_pagelist = vdso32_pagelist;
165 vdso_pages = vdso32_pages;
166 vdso_base = VDSO32_MBASE;
167 } else {
168 vdso_pagelist = vdso64_pagelist;
169 vdso_pages = vdso64_pages;
170 /*
171 * On 64bit we don't have a preferred map address. This
172 * allows get_unmapped_area to find an area near other mmaps
173 * and most likely share a SLB entry.
174 */
175 vdso_base = 0;
176 }
177#else
178 vdso_pagelist = vdso32_pagelist;
179 vdso_pages = vdso32_pages;
180 vdso_base = VDSO32_MBASE;
181#endif
182
183 current->mm->context.vdso_base = 0;
184
185 /* vDSO has a problem and was disabled, just don't "enable" it for the
186 * process
187 */
188 if (vdso_pages == 0)
189 return 0;
190 /* Add a page to the vdso size for the data page */
191 vdso_pages ++;
192
193 /*
194 * pick a base address for the vDSO in process space. We try to put it
195 * at vdso_base which is the "natural" base for it, but we might fail
196 * and end up putting it elsewhere.
197 * Add enough to the size so that the result can be aligned.
198 */
199 if (down_write_killable(&mm->mmap_sem))
200 return -EINTR;
201 vdso_base = get_unmapped_area(NULL, vdso_base,
202 (vdso_pages << PAGE_SHIFT) +
203 ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
204 0, 0);
205 if (IS_ERR_VALUE(vdso_base)) {
206 rc = vdso_base;
207 goto fail_mmapsem;
208 }
209
210 /* Add required alignment. */
211 vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
212
213 /*
214 * Put vDSO base into mm struct. We need to do this before calling
215 * install_special_mapping or the perf counter mmap tracking code
216 * will fail to recognise it as a vDSO (since arch_vma_name fails).
217 */
218 current->mm->context.vdso_base = vdso_base;
219
220 /*
221 * our vma flags don't have VM_WRITE so by default, the process isn't
222 * allowed to write those pages.
223 * gdb can break that with ptrace interface, and thus trigger COW on
224 * those pages but it's then your responsibility to never do that on
225 * the "data" page of the vDSO or you'll stop getting kernel updates
226 * and your nice userland gettimeofday will be totally dead.
227 * It's fine to use that for setting breakpoints in the vDSO code
228 * pages though.
229 */
230 rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
231 VM_READ|VM_EXEC|
232 VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
233 vdso_pagelist);
234 if (rc) {
235 current->mm->context.vdso_base = 0;
236 goto fail_mmapsem;
237 }
238
239 up_write(&mm->mmap_sem);
240 return 0;
241
242 fail_mmapsem:
243 up_write(&mm->mmap_sem);
244 return rc;
245}
246
247const char *arch_vma_name(struct vm_area_struct *vma)
248{
249 if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
250 return "[vdso]";
251 return NULL;
252}
253
254
255
256#ifdef CONFIG_VDSO32
257static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
258 unsigned long *size)
259{
260 Elf32_Shdr *sechdrs;
261 unsigned int i;
262 char *secnames;
263
264 /* Grab section headers and strings so we can tell who is who */
265 sechdrs = (void *)ehdr + ehdr->e_shoff;
266 secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
267
268 /* Find the section they want */
269 for (i = 1; i < ehdr->e_shnum; i++) {
270 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
271 if (size)
272 *size = sechdrs[i].sh_size;
273 return (void *)ehdr + sechdrs[i].sh_offset;
274 }
275 }
276 *size = 0;
277 return NULL;
278}
279
280static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
281 const char *symname)
282{
283 unsigned int i;
284 char name[MAX_SYMNAME], *c;
285
286 for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
287 if (lib->dynsym[i].st_name == 0)
288 continue;
289 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
290 MAX_SYMNAME);
291 c = strchr(name, '@');
292 if (c)
293 *c = 0;
294 if (strcmp(symname, name) == 0)
295 return &lib->dynsym[i];
296 }
297 return NULL;
298}
299
300/* Note that we assume the section is .text and the symbol is relative to
301 * the library base
302 */
303static unsigned long __init find_function32(struct lib32_elfinfo *lib,
304 const char *symname)
305{
306 Elf32_Sym *sym = find_symbol32(lib, symname);
307
308 if (sym == NULL) {
309 printk(KERN_WARNING "vDSO32: function %s not found !\n",
310 symname);
311 return 0;
312 }
313 return sym->st_value - VDSO32_LBASE;
314}
315
316static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
317 struct lib64_elfinfo *v64,
318 const char *orig, const char *fix)
319{
320 Elf32_Sym *sym32_gen, *sym32_fix;
321
322 sym32_gen = find_symbol32(v32, orig);
323 if (sym32_gen == NULL) {
324 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
325 return -1;
326 }
327 if (fix == NULL) {
328 sym32_gen->st_name = 0;
329 return 0;
330 }
331 sym32_fix = find_symbol32(v32, fix);
332 if (sym32_fix == NULL) {
333 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
334 return -1;
335 }
336 sym32_gen->st_value = sym32_fix->st_value;
337 sym32_gen->st_size = sym32_fix->st_size;
338 sym32_gen->st_info = sym32_fix->st_info;
339 sym32_gen->st_other = sym32_fix->st_other;
340 sym32_gen->st_shndx = sym32_fix->st_shndx;
341
342 return 0;
343}
344#else /* !CONFIG_VDSO32 */
345static unsigned long __init find_function32(struct lib32_elfinfo *lib,
346 const char *symname)
347{
348 return 0;
349}
350
351static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
352 struct lib64_elfinfo *v64,
353 const char *orig, const char *fix)
354{
355 return 0;
356}
357#endif /* CONFIG_VDSO32 */
358
359
360#ifdef CONFIG_PPC64
361
362static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
363 unsigned long *size)
364{
365 Elf64_Shdr *sechdrs;
366 unsigned int i;
367 char *secnames;
368
369 /* Grab section headers and strings so we can tell who is who */
370 sechdrs = (void *)ehdr + ehdr->e_shoff;
371 secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
372
373 /* Find the section they want */
374 for (i = 1; i < ehdr->e_shnum; i++) {
375 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
376 if (size)
377 *size = sechdrs[i].sh_size;
378 return (void *)ehdr + sechdrs[i].sh_offset;
379 }
380 }
381 if (size)
382 *size = 0;
383 return NULL;
384}
385
386static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
387 const char *symname)
388{
389 unsigned int i;
390 char name[MAX_SYMNAME], *c;
391
392 for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
393 if (lib->dynsym[i].st_name == 0)
394 continue;
395 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
396 MAX_SYMNAME);
397 c = strchr(name, '@');
398 if (c)
399 *c = 0;
400 if (strcmp(symname, name) == 0)
401 return &lib->dynsym[i];
402 }
403 return NULL;
404}
405
406/* Note that we assume the section is .text and the symbol is relative to
407 * the library base
408 */
409static unsigned long __init find_function64(struct lib64_elfinfo *lib,
410 const char *symname)
411{
412 Elf64_Sym *sym = find_symbol64(lib, symname);
413
414 if (sym == NULL) {
415 printk(KERN_WARNING "vDSO64: function %s not found !\n",
416 symname);
417 return 0;
418 }
419#ifdef VDS64_HAS_DESCRIPTORS
420 return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
421 VDSO64_LBASE;
422#else
423 return sym->st_value - VDSO64_LBASE;
424#endif
425}
426
427static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
428 struct lib64_elfinfo *v64,
429 const char *orig, const char *fix)
430{
431 Elf64_Sym *sym64_gen, *sym64_fix;
432
433 sym64_gen = find_symbol64(v64, orig);
434 if (sym64_gen == NULL) {
435 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
436 return -1;
437 }
438 if (fix == NULL) {
439 sym64_gen->st_name = 0;
440 return 0;
441 }
442 sym64_fix = find_symbol64(v64, fix);
443 if (sym64_fix == NULL) {
444 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
445 return -1;
446 }
447 sym64_gen->st_value = sym64_fix->st_value;
448 sym64_gen->st_size = sym64_fix->st_size;
449 sym64_gen->st_info = sym64_fix->st_info;
450 sym64_gen->st_other = sym64_fix->st_other;
451 sym64_gen->st_shndx = sym64_fix->st_shndx;
452
453 return 0;
454}
455
456#endif /* CONFIG_PPC64 */
457
458
459static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
460 struct lib64_elfinfo *v64)
461{
462 void *sect;
463
464 /*
465 * Locate symbol tables & text section
466 */
467
468#ifdef CONFIG_VDSO32
469 v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
470 v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
471 if (v32->dynsym == NULL || v32->dynstr == NULL) {
472 printk(KERN_ERR "vDSO32: required symbol section not found\n");
473 return -1;
474 }
475 sect = find_section32(v32->hdr, ".text", NULL);
476 if (sect == NULL) {
477 printk(KERN_ERR "vDSO32: the .text section was not found\n");
478 return -1;
479 }
480 v32->text = sect - vdso32_kbase;
481#endif
482
483#ifdef CONFIG_PPC64
484 v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
485 v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
486 if (v64->dynsym == NULL || v64->dynstr == NULL) {
487 printk(KERN_ERR "vDSO64: required symbol section not found\n");
488 return -1;
489 }
490 sect = find_section64(v64->hdr, ".text", NULL);
491 if (sect == NULL) {
492 printk(KERN_ERR "vDSO64: the .text section was not found\n");
493 return -1;
494 }
495 v64->text = sect - vdso64_kbase;
496#endif /* CONFIG_PPC64 */
497
498 return 0;
499}
500
501static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
502 struct lib64_elfinfo *v64)
503{
504 /*
505 * Find signal trampolines
506 */
507
508#ifdef CONFIG_PPC64
509 vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
510#endif
511 vdso32_sigtramp = find_function32(v32, "__kernel_sigtramp32");
512 vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
513}
514
515static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
516 struct lib64_elfinfo *v64)
517{
518#ifdef CONFIG_VDSO32
519 Elf32_Sym *sym32;
520#endif
521#ifdef CONFIG_PPC64
522 Elf64_Sym *sym64;
523
524 sym64 = find_symbol64(v64, "__kernel_datapage_offset");
525 if (sym64 == NULL) {
526 printk(KERN_ERR "vDSO64: Can't find symbol "
527 "__kernel_datapage_offset !\n");
528 return -1;
529 }
530 *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
531 (vdso64_pages << PAGE_SHIFT) -
532 (sym64->st_value - VDSO64_LBASE);
533#endif /* CONFIG_PPC64 */
534
535#ifdef CONFIG_VDSO32
536 sym32 = find_symbol32(v32, "__kernel_datapage_offset");
537 if (sym32 == NULL) {
538 printk(KERN_ERR "vDSO32: Can't find symbol "
539 "__kernel_datapage_offset !\n");
540 return -1;
541 }
542 *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
543 (vdso32_pages << PAGE_SHIFT) -
544 (sym32->st_value - VDSO32_LBASE);
545#endif
546
547 return 0;
548}
549
550
551static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
552 struct lib64_elfinfo *v64)
553{
554 unsigned long size;
555 void *start;
556
557#ifdef CONFIG_PPC64
558 start = find_section64(v64->hdr, "__ftr_fixup", &size);
559 if (start)
560 do_feature_fixups(cur_cpu_spec->cpu_features,
561 start, start + size);
562
563 start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);
564 if (start)
565 do_feature_fixups(cur_cpu_spec->mmu_features,
566 start, start + size);
567
568 start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);
569 if (start)
570 do_feature_fixups(powerpc_firmware_features,
571 start, start + size);
572
573 start = find_section64(v64->hdr, "__lwsync_fixup", &size);
574 if (start)
575 do_lwsync_fixups(cur_cpu_spec->cpu_features,
576 start, start + size);
577#endif /* CONFIG_PPC64 */
578
579#ifdef CONFIG_VDSO32
580 start = find_section32(v32->hdr, "__ftr_fixup", &size);
581 if (start)
582 do_feature_fixups(cur_cpu_spec->cpu_features,
583 start, start + size);
584
585 start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);
586 if (start)
587 do_feature_fixups(cur_cpu_spec->mmu_features,
588 start, start + size);
589
590#ifdef CONFIG_PPC64
591 start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);
592 if (start)
593 do_feature_fixups(powerpc_firmware_features,
594 start, start + size);
595#endif /* CONFIG_PPC64 */
596
597 start = find_section32(v32->hdr, "__lwsync_fixup", &size);
598 if (start)
599 do_lwsync_fixups(cur_cpu_spec->cpu_features,
600 start, start + size);
601#endif
602
603 return 0;
604}
605
606static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
607 struct lib64_elfinfo *v64)
608{
609 int i;
610
611 for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
612 struct vdso_patch_def *patch = &vdso_patches[i];
613 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
614 == patch->ftr_value;
615 if (!match)
616 continue;
617
618 DBG("replacing %s with %s...\n", patch->gen_name,
619 patch->fix_name ? "NONE" : patch->fix_name);
620
621 /*
622 * Patch the 32 bits and 64 bits symbols. Note that we do not
623 * patch the "." symbol on 64 bits.
624 * It would be easy to do, but doesn't seem to be necessary,
625 * patching the OPD symbol is enough.
626 */
627 vdso_do_func_patch32(v32, v64, patch->gen_name,
628 patch->fix_name);
629#ifdef CONFIG_PPC64
630 vdso_do_func_patch64(v32, v64, patch->gen_name,
631 patch->fix_name);
632#endif /* CONFIG_PPC64 */
633 }
634
635 return 0;
636}
637
638
639static __init int vdso_setup(void)
640{
641 struct lib32_elfinfo v32;
642 struct lib64_elfinfo v64;
643
644 v32.hdr = vdso32_kbase;
645#ifdef CONFIG_PPC64
646 v64.hdr = vdso64_kbase;
647#endif
648 if (vdso_do_find_sections(&v32, &v64))
649 return -1;
650
651 if (vdso_fixup_datapage(&v32, &v64))
652 return -1;
653
654 if (vdso_fixup_features(&v32, &v64))
655 return -1;
656
657 if (vdso_fixup_alt_funcs(&v32, &v64))
658 return -1;
659
660 vdso_setup_trampolines(&v32, &v64);
661
662 return 0;
663}
664
665/*
666 * Called from setup_arch to initialize the bitmap of available
667 * syscalls in the systemcfg page
668 */
669static void __init vdso_setup_syscall_map(void)
670{
671 unsigned int i;
672 extern unsigned long *sys_call_table;
673 extern unsigned long sys_ni_syscall;
674
675
676 for (i = 0; i < NR_syscalls; i++) {
677#ifdef CONFIG_PPC64
678 if (sys_call_table[i*2] != sys_ni_syscall)
679 vdso_data->syscall_map_64[i >> 5] |=
680 0x80000000UL >> (i & 0x1f);
681 if (sys_call_table[i*2+1] != sys_ni_syscall)
682 vdso_data->syscall_map_32[i >> 5] |=
683 0x80000000UL >> (i & 0x1f);
684#else /* CONFIG_PPC64 */
685 if (sys_call_table[i] != sys_ni_syscall)
686 vdso_data->syscall_map_32[i >> 5] |=
687 0x80000000UL >> (i & 0x1f);
688#endif /* CONFIG_PPC64 */
689 }
690}
691
692#ifdef CONFIG_PPC64
693int vdso_getcpu_init(void)
694{
695 unsigned long cpu, node, val;
696
697 /*
698 * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
699 * in the next 16 bits. The VDSO uses this to implement getcpu().
700 */
701 cpu = get_cpu();
702 WARN_ON_ONCE(cpu > 0xffff);
703
704 node = cpu_to_node(cpu);
705 WARN_ON_ONCE(node > 0xffff);
706
707 val = (cpu & 0xfff) | ((node & 0xffff) << 16);
708 mtspr(SPRN_SPRG_VDSO_WRITE, val);
709 get_paca()->sprg_vdso = val;
710
711 put_cpu();
712
713 return 0;
714}
715/* We need to call this before SMP init */
716early_initcall(vdso_getcpu_init);
717#endif
718
719static int __init vdso_init(void)
720{
721 int i;
722
723#ifdef CONFIG_PPC64
724 /*
725 * Fill up the "systemcfg" stuff for backward compatibility
726 */
727 strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
728 vdso_data->version.major = SYSTEMCFG_MAJOR;
729 vdso_data->version.minor = SYSTEMCFG_MINOR;
730 vdso_data->processor = mfspr(SPRN_PVR);
731 /*
732 * Fake the old platform number for pSeries and add
733 * in LPAR bit if necessary
734 */
735 vdso_data->platform = 0x100;
736 if (firmware_has_feature(FW_FEATURE_LPAR))
737 vdso_data->platform |= 1;
738 vdso_data->physicalMemorySize = memblock_phys_mem_size();
739 vdso_data->dcache_size = ppc64_caches.dsize;
740 vdso_data->dcache_line_size = ppc64_caches.dline_size;
741 vdso_data->icache_size = ppc64_caches.isize;
742 vdso_data->icache_line_size = ppc64_caches.iline_size;
743
744 /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
745 vdso_data->dcache_block_size = ppc64_caches.dline_size;
746 vdso_data->icache_block_size = ppc64_caches.iline_size;
747 vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
748 vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
749
750 /*
751 * Calculate the size of the 64 bits vDSO
752 */
753 vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
754 DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
755#else
756 vdso_data->dcache_block_size = L1_CACHE_BYTES;
757 vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
758 vdso_data->icache_block_size = L1_CACHE_BYTES;
759 vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
760#endif /* CONFIG_PPC64 */
761
762
763#ifdef CONFIG_VDSO32
764 vdso32_kbase = &vdso32_start;
765
766 /*
767 * Calculate the size of the 32 bits vDSO
768 */
769 vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
770 DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
771#endif
772
773
774 /*
775 * Setup the syscall map in the vDOS
776 */
777 vdso_setup_syscall_map();
778
779 /*
780 * Initialize the vDSO images in memory, that is do necessary
781 * fixups of vDSO symbols, locate trampolines, etc...
782 */
783 if (vdso_setup()) {
784 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
785 vdso32_pages = 0;
786#ifdef CONFIG_PPC64
787 vdso64_pages = 0;
788#endif
789 return 0;
790 }
791
792#ifdef CONFIG_VDSO32
793 /* Make sure pages are in the correct state */
794 vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
795 GFP_KERNEL);
796 BUG_ON(vdso32_pagelist == NULL);
797 for (i = 0; i < vdso32_pages; i++) {
798 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
799 ClearPageReserved(pg);
800 get_page(pg);
801 vdso32_pagelist[i] = pg;
802 }
803 vdso32_pagelist[i++] = virt_to_page(vdso_data);
804 vdso32_pagelist[i] = NULL;
805#endif
806
807#ifdef CONFIG_PPC64
808 vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
809 GFP_KERNEL);
810 BUG_ON(vdso64_pagelist == NULL);
811 for (i = 0; i < vdso64_pages; i++) {
812 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
813 ClearPageReserved(pg);
814 get_page(pg);
815 vdso64_pagelist[i] = pg;
816 }
817 vdso64_pagelist[i++] = virt_to_page(vdso_data);
818 vdso64_pagelist[i] = NULL;
819#endif /* CONFIG_PPC64 */
820
821 get_page(virt_to_page(vdso_data));
822
823 smp_wmb();
824 vdso_ready = 1;
825
826 return 0;
827}
828arch_initcall(vdso_init);