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1/*
2 * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
3 *
4 * PowerPC version
5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 * Copyright (C) 2001 IBM
7 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
8 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
9 *
10 * Derived from "arch/i386/kernel/signal.c"
11 * Copyright (C) 1991, 1992 Linus Torvalds
12 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 */
19
20#include <linux/sched.h>
21#include <linux/mm.h>
22#include <linux/smp.h>
23#include <linux/kernel.h>
24#include <linux/signal.h>
25#include <linux/errno.h>
26#include <linux/elf.h>
27#include <linux/ptrace.h>
28#include <linux/ratelimit.h>
29#ifdef CONFIG_PPC64
30#include <linux/syscalls.h>
31#include <linux/compat.h>
32#else
33#include <linux/wait.h>
34#include <linux/unistd.h>
35#include <linux/stddef.h>
36#include <linux/tty.h>
37#include <linux/binfmts.h>
38#endif
39
40#include <linux/uaccess.h>
41#include <asm/cacheflush.h>
42#include <asm/syscalls.h>
43#include <asm/sigcontext.h>
44#include <asm/vdso.h>
45#include <asm/switch_to.h>
46#include <asm/tm.h>
47#include <asm/asm-prototypes.h>
48#ifdef CONFIG_PPC64
49#include "ppc32.h"
50#include <asm/unistd.h>
51#else
52#include <asm/ucontext.h>
53#include <asm/pgtable.h>
54#endif
55
56#include "signal.h"
57
58
59#ifdef CONFIG_PPC64
60#define sys_rt_sigreturn compat_sys_rt_sigreturn
61#define sys_swapcontext compat_sys_swapcontext
62#define sys_sigreturn compat_sys_sigreturn
63
64#define old_sigaction old_sigaction32
65#define sigcontext sigcontext32
66#define mcontext mcontext32
67#define ucontext ucontext32
68
69#define __save_altstack __compat_save_altstack
70
71/*
72 * Userspace code may pass a ucontext which doesn't include VSX added
73 * at the end. We need to check for this case.
74 */
75#define UCONTEXTSIZEWITHOUTVSX \
76 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
77
78/*
79 * Returning 0 means we return to userspace via
80 * ret_from_except and thus restore all user
81 * registers from *regs. This is what we need
82 * to do when a signal has been delivered.
83 */
84
85#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
86#undef __SIGNAL_FRAMESIZE
87#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
88#undef ELF_NVRREG
89#define ELF_NVRREG ELF_NVRREG32
90
91/*
92 * Functions for flipping sigsets (thanks to brain dead generic
93 * implementation that makes things simple for little endian only)
94 */
95static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
96{
97 return put_compat_sigset(uset, set, sizeof(*uset));
98}
99
100static inline int get_sigset_t(sigset_t *set,
101 const compat_sigset_t __user *uset)
102{
103 return get_compat_sigset(set, uset);
104}
105
106#define to_user_ptr(p) ptr_to_compat(p)
107#define from_user_ptr(p) compat_ptr(p)
108
109static inline int save_general_regs(struct pt_regs *regs,
110 struct mcontext __user *frame)
111{
112 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
113 int i;
114 /* Force usr to alway see softe as 1 (interrupts enabled) */
115 elf_greg_t64 softe = 0x1;
116
117 WARN_ON(!FULL_REGS(regs));
118
119 for (i = 0; i <= PT_RESULT; i ++) {
120 if (i == 14 && !FULL_REGS(regs))
121 i = 32;
122 if ( i == PT_SOFTE) {
123 if(__put_user((unsigned int)softe, &frame->mc_gregs[i]))
124 return -EFAULT;
125 else
126 continue;
127 }
128 if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
129 return -EFAULT;
130 }
131 return 0;
132}
133
134static inline int restore_general_regs(struct pt_regs *regs,
135 struct mcontext __user *sr)
136{
137 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
138 int i;
139
140 for (i = 0; i <= PT_RESULT; i++) {
141 if ((i == PT_MSR) || (i == PT_SOFTE))
142 continue;
143 if (__get_user(gregs[i], &sr->mc_gregs[i]))
144 return -EFAULT;
145 }
146 return 0;
147}
148
149#else /* CONFIG_PPC64 */
150
151#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
152
153static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
154{
155 return copy_to_user(uset, set, sizeof(*uset));
156}
157
158static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
159{
160 return copy_from_user(set, uset, sizeof(*uset));
161}
162
163#define to_user_ptr(p) ((unsigned long)(p))
164#define from_user_ptr(p) ((void __user *)(p))
165
166static inline int save_general_regs(struct pt_regs *regs,
167 struct mcontext __user *frame)
168{
169 WARN_ON(!FULL_REGS(regs));
170 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
171}
172
173static inline int restore_general_regs(struct pt_regs *regs,
174 struct mcontext __user *sr)
175{
176 /* copy up to but not including MSR */
177 if (__copy_from_user(regs, &sr->mc_gregs,
178 PT_MSR * sizeof(elf_greg_t)))
179 return -EFAULT;
180 /* copy from orig_r3 (the word after the MSR) up to the end */
181 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
182 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
183 return -EFAULT;
184 return 0;
185}
186#endif
187
188/*
189 * When we have signals to deliver, we set up on the
190 * user stack, going down from the original stack pointer:
191 * an ABI gap of 56 words
192 * an mcontext struct
193 * a sigcontext struct
194 * a gap of __SIGNAL_FRAMESIZE bytes
195 *
196 * Each of these things must be a multiple of 16 bytes in size. The following
197 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
198 *
199 */
200struct sigframe {
201 struct sigcontext sctx; /* the sigcontext */
202 struct mcontext mctx; /* all the register values */
203#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
204 struct sigcontext sctx_transact;
205 struct mcontext mctx_transact;
206#endif
207 /*
208 * Programs using the rs6000/xcoff abi can save up to 19 gp
209 * regs and 18 fp regs below sp before decrementing it.
210 */
211 int abigap[56];
212};
213
214/* We use the mc_pad field for the signal return trampoline. */
215#define tramp mc_pad
216
217/*
218 * When we have rt signals to deliver, we set up on the
219 * user stack, going down from the original stack pointer:
220 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
221 * a gap of __SIGNAL_FRAMESIZE+16 bytes
222 * (the +16 is to get the siginfo and ucontext in the same
223 * positions as in older kernels).
224 *
225 * Each of these things must be a multiple of 16 bytes in size.
226 *
227 */
228struct rt_sigframe {
229#ifdef CONFIG_PPC64
230 compat_siginfo_t info;
231#else
232 struct siginfo info;
233#endif
234 struct ucontext uc;
235#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
236 struct ucontext uc_transact;
237#endif
238 /*
239 * Programs using the rs6000/xcoff abi can save up to 19 gp
240 * regs and 18 fp regs below sp before decrementing it.
241 */
242 int abigap[56];
243};
244
245#ifdef CONFIG_VSX
246unsigned long copy_fpr_to_user(void __user *to,
247 struct task_struct *task)
248{
249 u64 buf[ELF_NFPREG];
250 int i;
251
252 /* save FPR copy to local buffer then write to the thread_struct */
253 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
254 buf[i] = task->thread.TS_FPR(i);
255 buf[i] = task->thread.fp_state.fpscr;
256 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
257}
258
259unsigned long copy_fpr_from_user(struct task_struct *task,
260 void __user *from)
261{
262 u64 buf[ELF_NFPREG];
263 int i;
264
265 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
266 return 1;
267 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
268 task->thread.TS_FPR(i) = buf[i];
269 task->thread.fp_state.fpscr = buf[i];
270
271 return 0;
272}
273
274unsigned long copy_vsx_to_user(void __user *to,
275 struct task_struct *task)
276{
277 u64 buf[ELF_NVSRHALFREG];
278 int i;
279
280 /* save FPR copy to local buffer then write to the thread_struct */
281 for (i = 0; i < ELF_NVSRHALFREG; i++)
282 buf[i] = task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET];
283 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
284}
285
286unsigned long copy_vsx_from_user(struct task_struct *task,
287 void __user *from)
288{
289 u64 buf[ELF_NVSRHALFREG];
290 int i;
291
292 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
293 return 1;
294 for (i = 0; i < ELF_NVSRHALFREG ; i++)
295 task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
296 return 0;
297}
298
299#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
300unsigned long copy_ckfpr_to_user(void __user *to,
301 struct task_struct *task)
302{
303 u64 buf[ELF_NFPREG];
304 int i;
305
306 /* save FPR copy to local buffer then write to the thread_struct */
307 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
308 buf[i] = task->thread.TS_CKFPR(i);
309 buf[i] = task->thread.ckfp_state.fpscr;
310 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
311}
312
313unsigned long copy_ckfpr_from_user(struct task_struct *task,
314 void __user *from)
315{
316 u64 buf[ELF_NFPREG];
317 int i;
318
319 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
320 return 1;
321 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
322 task->thread.TS_CKFPR(i) = buf[i];
323 task->thread.ckfp_state.fpscr = buf[i];
324
325 return 0;
326}
327
328unsigned long copy_ckvsx_to_user(void __user *to,
329 struct task_struct *task)
330{
331 u64 buf[ELF_NVSRHALFREG];
332 int i;
333
334 /* save FPR copy to local buffer then write to the thread_struct */
335 for (i = 0; i < ELF_NVSRHALFREG; i++)
336 buf[i] = task->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET];
337 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
338}
339
340unsigned long copy_ckvsx_from_user(struct task_struct *task,
341 void __user *from)
342{
343 u64 buf[ELF_NVSRHALFREG];
344 int i;
345
346 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
347 return 1;
348 for (i = 0; i < ELF_NVSRHALFREG ; i++)
349 task->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
350 return 0;
351}
352#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
353#else
354inline unsigned long copy_fpr_to_user(void __user *to,
355 struct task_struct *task)
356{
357 return __copy_to_user(to, task->thread.fp_state.fpr,
358 ELF_NFPREG * sizeof(double));
359}
360
361inline unsigned long copy_fpr_from_user(struct task_struct *task,
362 void __user *from)
363{
364 return __copy_from_user(task->thread.fp_state.fpr, from,
365 ELF_NFPREG * sizeof(double));
366}
367
368#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
369inline unsigned long copy_ckfpr_to_user(void __user *to,
370 struct task_struct *task)
371{
372 return __copy_to_user(to, task->thread.ckfp_state.fpr,
373 ELF_NFPREG * sizeof(double));
374}
375
376inline unsigned long copy_ckfpr_from_user(struct task_struct *task,
377 void __user *from)
378{
379 return __copy_from_user(task->thread.ckfp_state.fpr, from,
380 ELF_NFPREG * sizeof(double));
381}
382#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
383#endif
384
385/*
386 * Save the current user registers on the user stack.
387 * We only save the altivec/spe registers if the process has used
388 * altivec/spe instructions at some point.
389 */
390static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
391 struct mcontext __user *tm_frame, int sigret,
392 int ctx_has_vsx_region)
393{
394 unsigned long msr = regs->msr;
395
396 /* Make sure floating point registers are stored in regs */
397 flush_fp_to_thread(current);
398
399 /* save general registers */
400 if (save_general_regs(regs, frame))
401 return 1;
402
403#ifdef CONFIG_ALTIVEC
404 /* save altivec registers */
405 if (current->thread.used_vr) {
406 flush_altivec_to_thread(current);
407 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
408 ELF_NVRREG * sizeof(vector128)))
409 return 1;
410 /* set MSR_VEC in the saved MSR value to indicate that
411 frame->mc_vregs contains valid data */
412 msr |= MSR_VEC;
413 }
414 /* else assert((regs->msr & MSR_VEC) == 0) */
415
416 /* We always copy to/from vrsave, it's 0 if we don't have or don't
417 * use altivec. Since VSCR only contains 32 bits saved in the least
418 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
419 * most significant bits of that same vector. --BenH
420 * Note that the current VRSAVE value is in the SPR at this point.
421 */
422 if (cpu_has_feature(CPU_FTR_ALTIVEC))
423 current->thread.vrsave = mfspr(SPRN_VRSAVE);
424 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
425 return 1;
426#endif /* CONFIG_ALTIVEC */
427 if (copy_fpr_to_user(&frame->mc_fregs, current))
428 return 1;
429
430 /*
431 * Clear the MSR VSX bit to indicate there is no valid state attached
432 * to this context, except in the specific case below where we set it.
433 */
434 msr &= ~MSR_VSX;
435#ifdef CONFIG_VSX
436 /*
437 * Copy VSR 0-31 upper half from thread_struct to local
438 * buffer, then write that to userspace. Also set MSR_VSX in
439 * the saved MSR value to indicate that frame->mc_vregs
440 * contains valid data
441 */
442 if (current->thread.used_vsr && ctx_has_vsx_region) {
443 flush_vsx_to_thread(current);
444 if (copy_vsx_to_user(&frame->mc_vsregs, current))
445 return 1;
446 msr |= MSR_VSX;
447 }
448#endif /* CONFIG_VSX */
449#ifdef CONFIG_SPE
450 /* save spe registers */
451 if (current->thread.used_spe) {
452 flush_spe_to_thread(current);
453 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
454 ELF_NEVRREG * sizeof(u32)))
455 return 1;
456 /* set MSR_SPE in the saved MSR value to indicate that
457 frame->mc_vregs contains valid data */
458 msr |= MSR_SPE;
459 }
460 /* else assert((regs->msr & MSR_SPE) == 0) */
461
462 /* We always copy to/from spefscr */
463 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
464 return 1;
465#endif /* CONFIG_SPE */
466
467 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
468 return 1;
469 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
470 * can check it on the restore to see if TM is active
471 */
472 if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
473 return 1;
474
475 if (sigret) {
476 /* Set up the sigreturn trampoline: li r0,sigret; sc */
477 if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
478 || __put_user(0x44000002UL, &frame->tramp[1]))
479 return 1;
480 flush_icache_range((unsigned long) &frame->tramp[0],
481 (unsigned long) &frame->tramp[2]);
482 }
483
484 return 0;
485}
486
487#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
488/*
489 * Save the current user registers on the user stack.
490 * We only save the altivec/spe registers if the process has used
491 * altivec/spe instructions at some point.
492 * We also save the transactional registers to a second ucontext in the
493 * frame.
494 *
495 * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
496 */
497static int save_tm_user_regs(struct pt_regs *regs,
498 struct mcontext __user *frame,
499 struct mcontext __user *tm_frame, int sigret)
500{
501 unsigned long msr = regs->msr;
502
503 WARN_ON(tm_suspend_disabled);
504
505 /* Remove TM bits from thread's MSR. The MSR in the sigcontext
506 * just indicates to userland that we were doing a transaction, but we
507 * don't want to return in transactional state. This also ensures
508 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
509 */
510 regs->msr &= ~MSR_TS_MASK;
511
512 /* Save both sets of general registers */
513 if (save_general_regs(¤t->thread.ckpt_regs, frame)
514 || save_general_regs(regs, tm_frame))
515 return 1;
516
517 /* Stash the top half of the 64bit MSR into the 32bit MSR word
518 * of the transactional mcontext. This way we have a backward-compatible
519 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
520 * also look at what type of transaction (T or S) was active at the
521 * time of the signal.
522 */
523 if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
524 return 1;
525
526#ifdef CONFIG_ALTIVEC
527 /* save altivec registers */
528 if (current->thread.used_vr) {
529 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
530 ELF_NVRREG * sizeof(vector128)))
531 return 1;
532 if (msr & MSR_VEC) {
533 if (__copy_to_user(&tm_frame->mc_vregs,
534 ¤t->thread.vr_state,
535 ELF_NVRREG * sizeof(vector128)))
536 return 1;
537 } else {
538 if (__copy_to_user(&tm_frame->mc_vregs,
539 ¤t->thread.ckvr_state,
540 ELF_NVRREG * sizeof(vector128)))
541 return 1;
542 }
543
544 /* set MSR_VEC in the saved MSR value to indicate that
545 * frame->mc_vregs contains valid data
546 */
547 msr |= MSR_VEC;
548 }
549
550 /* We always copy to/from vrsave, it's 0 if we don't have or don't
551 * use altivec. Since VSCR only contains 32 bits saved in the least
552 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
553 * most significant bits of that same vector. --BenH
554 */
555 if (cpu_has_feature(CPU_FTR_ALTIVEC))
556 current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
557 if (__put_user(current->thread.ckvrsave,
558 (u32 __user *)&frame->mc_vregs[32]))
559 return 1;
560 if (msr & MSR_VEC) {
561 if (__put_user(current->thread.vrsave,
562 (u32 __user *)&tm_frame->mc_vregs[32]))
563 return 1;
564 } else {
565 if (__put_user(current->thread.ckvrsave,
566 (u32 __user *)&tm_frame->mc_vregs[32]))
567 return 1;
568 }
569#endif /* CONFIG_ALTIVEC */
570
571 if (copy_ckfpr_to_user(&frame->mc_fregs, current))
572 return 1;
573 if (msr & MSR_FP) {
574 if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
575 return 1;
576 } else {
577 if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
578 return 1;
579 }
580
581#ifdef CONFIG_VSX
582 /*
583 * Copy VSR 0-31 upper half from thread_struct to local
584 * buffer, then write that to userspace. Also set MSR_VSX in
585 * the saved MSR value to indicate that frame->mc_vregs
586 * contains valid data
587 */
588 if (current->thread.used_vsr) {
589 if (copy_ckvsx_to_user(&frame->mc_vsregs, current))
590 return 1;
591 if (msr & MSR_VSX) {
592 if (copy_vsx_to_user(&tm_frame->mc_vsregs,
593 current))
594 return 1;
595 } else {
596 if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
597 return 1;
598 }
599
600 msr |= MSR_VSX;
601 }
602#endif /* CONFIG_VSX */
603#ifdef CONFIG_SPE
604 /* SPE regs are not checkpointed with TM, so this section is
605 * simply the same as in save_user_regs().
606 */
607 if (current->thread.used_spe) {
608 flush_spe_to_thread(current);
609 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
610 ELF_NEVRREG * sizeof(u32)))
611 return 1;
612 /* set MSR_SPE in the saved MSR value to indicate that
613 * frame->mc_vregs contains valid data */
614 msr |= MSR_SPE;
615 }
616
617 /* We always copy to/from spefscr */
618 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
619 return 1;
620#endif /* CONFIG_SPE */
621
622 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
623 return 1;
624 if (sigret) {
625 /* Set up the sigreturn trampoline: li r0,sigret; sc */
626 if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
627 || __put_user(0x44000002UL, &frame->tramp[1]))
628 return 1;
629 flush_icache_range((unsigned long) &frame->tramp[0],
630 (unsigned long) &frame->tramp[2]);
631 }
632
633 return 0;
634}
635#endif
636
637/*
638 * Restore the current user register values from the user stack,
639 * (except for MSR).
640 */
641static long restore_user_regs(struct pt_regs *regs,
642 struct mcontext __user *sr, int sig)
643{
644 long err;
645 unsigned int save_r2 = 0;
646 unsigned long msr;
647#ifdef CONFIG_VSX
648 int i;
649#endif
650
651 /*
652 * restore general registers but not including MSR or SOFTE. Also
653 * take care of keeping r2 (TLS) intact if not a signal
654 */
655 if (!sig)
656 save_r2 = (unsigned int)regs->gpr[2];
657 err = restore_general_regs(regs, sr);
658 regs->trap = 0;
659 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
660 if (!sig)
661 regs->gpr[2] = (unsigned long) save_r2;
662 if (err)
663 return 1;
664
665 /* if doing signal return, restore the previous little-endian mode */
666 if (sig)
667 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
668
669#ifdef CONFIG_ALTIVEC
670 /*
671 * Force the process to reload the altivec registers from
672 * current->thread when it next does altivec instructions
673 */
674 regs->msr &= ~MSR_VEC;
675 if (msr & MSR_VEC) {
676 /* restore altivec registers from the stack */
677 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
678 sizeof(sr->mc_vregs)))
679 return 1;
680 current->thread.used_vr = true;
681 } else if (current->thread.used_vr)
682 memset(¤t->thread.vr_state, 0,
683 ELF_NVRREG * sizeof(vector128));
684
685 /* Always get VRSAVE back */
686 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
687 return 1;
688 if (cpu_has_feature(CPU_FTR_ALTIVEC))
689 mtspr(SPRN_VRSAVE, current->thread.vrsave);
690#endif /* CONFIG_ALTIVEC */
691 if (copy_fpr_from_user(current, &sr->mc_fregs))
692 return 1;
693
694#ifdef CONFIG_VSX
695 /*
696 * Force the process to reload the VSX registers from
697 * current->thread when it next does VSX instruction.
698 */
699 regs->msr &= ~MSR_VSX;
700 if (msr & MSR_VSX) {
701 /*
702 * Restore altivec registers from the stack to a local
703 * buffer, then write this out to the thread_struct
704 */
705 if (copy_vsx_from_user(current, &sr->mc_vsregs))
706 return 1;
707 current->thread.used_vsr = true;
708 } else if (current->thread.used_vsr)
709 for (i = 0; i < 32 ; i++)
710 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
711#endif /* CONFIG_VSX */
712 /*
713 * force the process to reload the FP registers from
714 * current->thread when it next does FP instructions
715 */
716 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
717
718#ifdef CONFIG_SPE
719 /* force the process to reload the spe registers from
720 current->thread when it next does spe instructions */
721 regs->msr &= ~MSR_SPE;
722 if (msr & MSR_SPE) {
723 /* restore spe registers from the stack */
724 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
725 ELF_NEVRREG * sizeof(u32)))
726 return 1;
727 current->thread.used_spe = true;
728 } else if (current->thread.used_spe)
729 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
730
731 /* Always get SPEFSCR back */
732 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
733 return 1;
734#endif /* CONFIG_SPE */
735
736 return 0;
737}
738
739#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
740/*
741 * Restore the current user register values from the user stack, except for
742 * MSR, and recheckpoint the original checkpointed register state for processes
743 * in transactions.
744 */
745static long restore_tm_user_regs(struct pt_regs *regs,
746 struct mcontext __user *sr,
747 struct mcontext __user *tm_sr)
748{
749 long err;
750 unsigned long msr, msr_hi;
751#ifdef CONFIG_VSX
752 int i;
753#endif
754
755 if (tm_suspend_disabled)
756 return 1;
757 /*
758 * restore general registers but not including MSR or SOFTE. Also
759 * take care of keeping r2 (TLS) intact if not a signal.
760 * See comment in signal_64.c:restore_tm_sigcontexts();
761 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
762 * were set by the signal delivery.
763 */
764 err = restore_general_regs(regs, tm_sr);
765 err |= restore_general_regs(¤t->thread.ckpt_regs, sr);
766
767 err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
768
769 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
770 if (err)
771 return 1;
772
773 /* Restore the previous little-endian mode */
774 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
775
776#ifdef CONFIG_ALTIVEC
777 regs->msr &= ~MSR_VEC;
778 if (msr & MSR_VEC) {
779 /* restore altivec registers from the stack */
780 if (__copy_from_user(¤t->thread.ckvr_state, &sr->mc_vregs,
781 sizeof(sr->mc_vregs)) ||
782 __copy_from_user(¤t->thread.vr_state,
783 &tm_sr->mc_vregs,
784 sizeof(sr->mc_vregs)))
785 return 1;
786 current->thread.used_vr = true;
787 } else if (current->thread.used_vr) {
788 memset(¤t->thread.vr_state, 0,
789 ELF_NVRREG * sizeof(vector128));
790 memset(¤t->thread.ckvr_state, 0,
791 ELF_NVRREG * sizeof(vector128));
792 }
793
794 /* Always get VRSAVE back */
795 if (__get_user(current->thread.ckvrsave,
796 (u32 __user *)&sr->mc_vregs[32]) ||
797 __get_user(current->thread.vrsave,
798 (u32 __user *)&tm_sr->mc_vregs[32]))
799 return 1;
800 if (cpu_has_feature(CPU_FTR_ALTIVEC))
801 mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
802#endif /* CONFIG_ALTIVEC */
803
804 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
805
806 if (copy_fpr_from_user(current, &sr->mc_fregs) ||
807 copy_ckfpr_from_user(current, &tm_sr->mc_fregs))
808 return 1;
809
810#ifdef CONFIG_VSX
811 regs->msr &= ~MSR_VSX;
812 if (msr & MSR_VSX) {
813 /*
814 * Restore altivec registers from the stack to a local
815 * buffer, then write this out to the thread_struct
816 */
817 if (copy_vsx_from_user(current, &tm_sr->mc_vsregs) ||
818 copy_ckvsx_from_user(current, &sr->mc_vsregs))
819 return 1;
820 current->thread.used_vsr = true;
821 } else if (current->thread.used_vsr)
822 for (i = 0; i < 32 ; i++) {
823 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
824 current->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
825 }
826#endif /* CONFIG_VSX */
827
828#ifdef CONFIG_SPE
829 /* SPE regs are not checkpointed with TM, so this section is
830 * simply the same as in restore_user_regs().
831 */
832 regs->msr &= ~MSR_SPE;
833 if (msr & MSR_SPE) {
834 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
835 ELF_NEVRREG * sizeof(u32)))
836 return 1;
837 current->thread.used_spe = true;
838 } else if (current->thread.used_spe)
839 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
840
841 /* Always get SPEFSCR back */
842 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
843 + ELF_NEVRREG))
844 return 1;
845#endif /* CONFIG_SPE */
846
847 /* Get the top half of the MSR from the user context */
848 if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
849 return 1;
850 msr_hi <<= 32;
851 /* If TM bits are set to the reserved value, it's an invalid context */
852 if (MSR_TM_RESV(msr_hi))
853 return 1;
854 /* Pull in the MSR TM bits from the user context */
855 regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK);
856 /* Now, recheckpoint. This loads up all of the checkpointed (older)
857 * registers, including FP and V[S]Rs. After recheckpointing, the
858 * transactional versions should be loaded.
859 */
860 tm_enable();
861 /* Make sure the transaction is marked as failed */
862 current->thread.tm_texasr |= TEXASR_FS;
863 /* This loads the checkpointed FP/VEC state, if used */
864 tm_recheckpoint(¤t->thread);
865
866 /* This loads the speculative FP/VEC state, if used */
867 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
868 if (msr & MSR_FP) {
869 load_fp_state(¤t->thread.fp_state);
870 regs->msr |= (MSR_FP | current->thread.fpexc_mode);
871 }
872#ifdef CONFIG_ALTIVEC
873 if (msr & MSR_VEC) {
874 load_vr_state(¤t->thread.vr_state);
875 regs->msr |= MSR_VEC;
876 }
877#endif
878
879 return 0;
880}
881#endif
882
883#ifdef CONFIG_PPC64
884
885#define copy_siginfo_to_user copy_siginfo_to_user32
886
887#endif /* CONFIG_PPC64 */
888
889/*
890 * Set up a signal frame for a "real-time" signal handler
891 * (one which gets siginfo).
892 */
893int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
894 struct task_struct *tsk)
895{
896 struct rt_sigframe __user *rt_sf;
897 struct mcontext __user *frame;
898 struct mcontext __user *tm_frame = NULL;
899 void __user *addr;
900 unsigned long newsp = 0;
901 int sigret;
902 unsigned long tramp;
903 struct pt_regs *regs = tsk->thread.regs;
904
905 BUG_ON(tsk != current);
906
907 /* Set up Signal Frame */
908 /* Put a Real Time Context onto stack */
909 rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
910 addr = rt_sf;
911 if (unlikely(rt_sf == NULL))
912 goto badframe;
913
914 /* Put the siginfo & fill in most of the ucontext */
915 if (copy_siginfo_to_user(&rt_sf->info, &ksig->info)
916 || __put_user(0, &rt_sf->uc.uc_flags)
917 || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
918 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
919 &rt_sf->uc.uc_regs)
920 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
921 goto badframe;
922
923 /* Save user registers on the stack */
924 frame = &rt_sf->uc.uc_mcontext;
925 addr = frame;
926 if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
927 sigret = 0;
928 tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
929 } else {
930 sigret = __NR_rt_sigreturn;
931 tramp = (unsigned long) frame->tramp;
932 }
933
934#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
935 tm_frame = &rt_sf->uc_transact.uc_mcontext;
936 if (MSR_TM_ACTIVE(regs->msr)) {
937 if (__put_user((unsigned long)&rt_sf->uc_transact,
938 &rt_sf->uc.uc_link) ||
939 __put_user((unsigned long)tm_frame,
940 &rt_sf->uc_transact.uc_regs))
941 goto badframe;
942 if (save_tm_user_regs(regs, frame, tm_frame, sigret))
943 goto badframe;
944 }
945 else
946#endif
947 {
948 if (__put_user(0, &rt_sf->uc.uc_link))
949 goto badframe;
950 if (save_user_regs(regs, frame, tm_frame, sigret, 1))
951 goto badframe;
952 }
953 regs->link = tramp;
954
955 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
956
957 /* create a stack frame for the caller of the handler */
958 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
959 addr = (void __user *)regs->gpr[1];
960 if (put_user(regs->gpr[1], (u32 __user *)newsp))
961 goto badframe;
962
963 /* Fill registers for signal handler */
964 regs->gpr[1] = newsp;
965 regs->gpr[3] = ksig->sig;
966 regs->gpr[4] = (unsigned long) &rt_sf->info;
967 regs->gpr[5] = (unsigned long) &rt_sf->uc;
968 regs->gpr[6] = (unsigned long) rt_sf;
969 regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
970 /* enter the signal handler in native-endian mode */
971 regs->msr &= ~MSR_LE;
972 regs->msr |= (MSR_KERNEL & MSR_LE);
973 return 0;
974
975badframe:
976 if (show_unhandled_signals)
977 printk_ratelimited(KERN_INFO
978 "%s[%d]: bad frame in handle_rt_signal32: "
979 "%p nip %08lx lr %08lx\n",
980 tsk->comm, tsk->pid,
981 addr, regs->nip, regs->link);
982
983 return 1;
984}
985
986static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
987{
988 sigset_t set;
989 struct mcontext __user *mcp;
990
991 if (get_sigset_t(&set, &ucp->uc_sigmask))
992 return -EFAULT;
993#ifdef CONFIG_PPC64
994 {
995 u32 cmcp;
996
997 if (__get_user(cmcp, &ucp->uc_regs))
998 return -EFAULT;
999 mcp = (struct mcontext __user *)(u64)cmcp;
1000 /* no need to check access_ok(mcp), since mcp < 4GB */
1001 }
1002#else
1003 if (__get_user(mcp, &ucp->uc_regs))
1004 return -EFAULT;
1005 if (!access_ok(VERIFY_READ, mcp, sizeof(*mcp)))
1006 return -EFAULT;
1007#endif
1008 set_current_blocked(&set);
1009 if (restore_user_regs(regs, mcp, sig))
1010 return -EFAULT;
1011
1012 return 0;
1013}
1014
1015#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1016static int do_setcontext_tm(struct ucontext __user *ucp,
1017 struct ucontext __user *tm_ucp,
1018 struct pt_regs *regs)
1019{
1020 sigset_t set;
1021 struct mcontext __user *mcp;
1022 struct mcontext __user *tm_mcp;
1023 u32 cmcp;
1024 u32 tm_cmcp;
1025
1026 if (get_sigset_t(&set, &ucp->uc_sigmask))
1027 return -EFAULT;
1028
1029 if (__get_user(cmcp, &ucp->uc_regs) ||
1030 __get_user(tm_cmcp, &tm_ucp->uc_regs))
1031 return -EFAULT;
1032 mcp = (struct mcontext __user *)(u64)cmcp;
1033 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
1034 /* no need to check access_ok(mcp), since mcp < 4GB */
1035
1036 set_current_blocked(&set);
1037 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1038 return -EFAULT;
1039
1040 return 0;
1041}
1042#endif
1043
1044long sys_swapcontext(struct ucontext __user *old_ctx,
1045 struct ucontext __user *new_ctx,
1046 int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
1047{
1048 unsigned char tmp __maybe_unused;
1049 int ctx_has_vsx_region = 0;
1050
1051#ifdef CONFIG_PPC64
1052 unsigned long new_msr = 0;
1053
1054 if (new_ctx) {
1055 struct mcontext __user *mcp;
1056 u32 cmcp;
1057
1058 /*
1059 * Get pointer to the real mcontext. No need for
1060 * access_ok since we are dealing with compat
1061 * pointers.
1062 */
1063 if (__get_user(cmcp, &new_ctx->uc_regs))
1064 return -EFAULT;
1065 mcp = (struct mcontext __user *)(u64)cmcp;
1066 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
1067 return -EFAULT;
1068 }
1069 /*
1070 * Check that the context is not smaller than the original
1071 * size (with VMX but without VSX)
1072 */
1073 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
1074 return -EINVAL;
1075 /*
1076 * If the new context state sets the MSR VSX bits but
1077 * it doesn't provide VSX state.
1078 */
1079 if ((ctx_size < sizeof(struct ucontext)) &&
1080 (new_msr & MSR_VSX))
1081 return -EINVAL;
1082 /* Does the context have enough room to store VSX data? */
1083 if (ctx_size >= sizeof(struct ucontext))
1084 ctx_has_vsx_region = 1;
1085#else
1086 /* Context size is for future use. Right now, we only make sure
1087 * we are passed something we understand
1088 */
1089 if (ctx_size < sizeof(struct ucontext))
1090 return -EINVAL;
1091#endif
1092 if (old_ctx != NULL) {
1093 struct mcontext __user *mctx;
1094
1095 /*
1096 * old_ctx might not be 16-byte aligned, in which
1097 * case old_ctx->uc_mcontext won't be either.
1098 * Because we have the old_ctx->uc_pad2 field
1099 * before old_ctx->uc_mcontext, we need to round down
1100 * from &old_ctx->uc_mcontext to a 16-byte boundary.
1101 */
1102 mctx = (struct mcontext __user *)
1103 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
1104 if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size)
1105 || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
1106 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
1107 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
1108 return -EFAULT;
1109 }
1110 if (new_ctx == NULL)
1111 return 0;
1112 if (!access_ok(VERIFY_READ, new_ctx, ctx_size)
1113 || __get_user(tmp, (u8 __user *) new_ctx)
1114 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
1115 return -EFAULT;
1116
1117 /*
1118 * If we get a fault copying the context into the kernel's
1119 * image of the user's registers, we can't just return -EFAULT
1120 * because the user's registers will be corrupted. For instance
1121 * the NIP value may have been updated but not some of the
1122 * other registers. Given that we have done the access_ok
1123 * and successfully read the first and last bytes of the region
1124 * above, this should only happen in an out-of-memory situation
1125 * or if another thread unmaps the region containing the context.
1126 * We kill the task with a SIGSEGV in this situation.
1127 */
1128 if (do_setcontext(new_ctx, regs, 0))
1129 do_exit(SIGSEGV);
1130
1131 set_thread_flag(TIF_RESTOREALL);
1132 return 0;
1133}
1134
1135long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1136 struct pt_regs *regs)
1137{
1138 struct rt_sigframe __user *rt_sf;
1139#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1140 struct ucontext __user *uc_transact;
1141 unsigned long msr_hi;
1142 unsigned long tmp;
1143 int tm_restore = 0;
1144#endif
1145 /* Always make any pending restarted system calls return -EINTR */
1146 current->restart_block.fn = do_no_restart_syscall;
1147
1148 rt_sf = (struct rt_sigframe __user *)
1149 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1150 if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
1151 goto bad;
1152
1153#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1154 /*
1155 * If there is a transactional state then throw it away.
1156 * The purpose of a sigreturn is to destroy all traces of the
1157 * signal frame, this includes any transactional state created
1158 * within in. We only check for suspended as we can never be
1159 * active in the kernel, we are active, there is nothing better to
1160 * do than go ahead and Bad Thing later.
1161 * The cause is not important as there will never be a
1162 * recheckpoint so it's not user visible.
1163 */
1164 if (MSR_TM_SUSPENDED(mfmsr()))
1165 tm_reclaim_current(0);
1166
1167 if (__get_user(tmp, &rt_sf->uc.uc_link))
1168 goto bad;
1169 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1170 if (uc_transact) {
1171 u32 cmcp;
1172 struct mcontext __user *mcp;
1173
1174 if (__get_user(cmcp, &uc_transact->uc_regs))
1175 return -EFAULT;
1176 mcp = (struct mcontext __user *)(u64)cmcp;
1177 /* The top 32 bits of the MSR are stashed in the transactional
1178 * ucontext. */
1179 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1180 goto bad;
1181
1182 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1183 /* We only recheckpoint on return if we're
1184 * transaction.
1185 */
1186 tm_restore = 1;
1187 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1188 goto bad;
1189 }
1190 }
1191 if (!tm_restore)
1192 /* Fall through, for non-TM restore */
1193#endif
1194 if (do_setcontext(&rt_sf->uc, regs, 1))
1195 goto bad;
1196
1197 /*
1198 * It's not clear whether or why it is desirable to save the
1199 * sigaltstack setting on signal delivery and restore it on
1200 * signal return. But other architectures do this and we have
1201 * always done it up until now so it is probably better not to
1202 * change it. -- paulus
1203 */
1204#ifdef CONFIG_PPC64
1205 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1206 goto bad;
1207#else
1208 if (restore_altstack(&rt_sf->uc.uc_stack))
1209 goto bad;
1210#endif
1211 set_thread_flag(TIF_RESTOREALL);
1212 return 0;
1213
1214 bad:
1215 if (show_unhandled_signals)
1216 printk_ratelimited(KERN_INFO
1217 "%s[%d]: bad frame in sys_rt_sigreturn: "
1218 "%p nip %08lx lr %08lx\n",
1219 current->comm, current->pid,
1220 rt_sf, regs->nip, regs->link);
1221
1222 force_sig(SIGSEGV, current);
1223 return 0;
1224}
1225
1226#ifdef CONFIG_PPC32
1227int sys_debug_setcontext(struct ucontext __user *ctx,
1228 int ndbg, struct sig_dbg_op __user *dbg,
1229 int r6, int r7, int r8,
1230 struct pt_regs *regs)
1231{
1232 struct sig_dbg_op op;
1233 int i;
1234 unsigned char tmp __maybe_unused;
1235 unsigned long new_msr = regs->msr;
1236#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1237 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1238#endif
1239
1240 for (i=0; i<ndbg; i++) {
1241 if (copy_from_user(&op, dbg + i, sizeof(op)))
1242 return -EFAULT;
1243 switch (op.dbg_type) {
1244 case SIG_DBG_SINGLE_STEPPING:
1245#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1246 if (op.dbg_value) {
1247 new_msr |= MSR_DE;
1248 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1249 } else {
1250 new_dbcr0 &= ~DBCR0_IC;
1251 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1252 current->thread.debug.dbcr1)) {
1253 new_msr &= ~MSR_DE;
1254 new_dbcr0 &= ~DBCR0_IDM;
1255 }
1256 }
1257#else
1258 if (op.dbg_value)
1259 new_msr |= MSR_SE;
1260 else
1261 new_msr &= ~MSR_SE;
1262#endif
1263 break;
1264 case SIG_DBG_BRANCH_TRACING:
1265#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1266 return -EINVAL;
1267#else
1268 if (op.dbg_value)
1269 new_msr |= MSR_BE;
1270 else
1271 new_msr &= ~MSR_BE;
1272#endif
1273 break;
1274
1275 default:
1276 return -EINVAL;
1277 }
1278 }
1279
1280 /* We wait until here to actually install the values in the
1281 registers so if we fail in the above loop, it will not
1282 affect the contents of these registers. After this point,
1283 failure is a problem, anyway, and it's very unlikely unless
1284 the user is really doing something wrong. */
1285 regs->msr = new_msr;
1286#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1287 current->thread.debug.dbcr0 = new_dbcr0;
1288#endif
1289
1290 if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx))
1291 || __get_user(tmp, (u8 __user *) ctx)
1292 || __get_user(tmp, (u8 __user *) (ctx + 1) - 1))
1293 return -EFAULT;
1294
1295 /*
1296 * If we get a fault copying the context into the kernel's
1297 * image of the user's registers, we can't just return -EFAULT
1298 * because the user's registers will be corrupted. For instance
1299 * the NIP value may have been updated but not some of the
1300 * other registers. Given that we have done the access_ok
1301 * and successfully read the first and last bytes of the region
1302 * above, this should only happen in an out-of-memory situation
1303 * or if another thread unmaps the region containing the context.
1304 * We kill the task with a SIGSEGV in this situation.
1305 */
1306 if (do_setcontext(ctx, regs, 1)) {
1307 if (show_unhandled_signals)
1308 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1309 "sys_debug_setcontext: %p nip %08lx "
1310 "lr %08lx\n",
1311 current->comm, current->pid,
1312 ctx, regs->nip, regs->link);
1313
1314 force_sig(SIGSEGV, current);
1315 goto out;
1316 }
1317
1318 /*
1319 * It's not clear whether or why it is desirable to save the
1320 * sigaltstack setting on signal delivery and restore it on
1321 * signal return. But other architectures do this and we have
1322 * always done it up until now so it is probably better not to
1323 * change it. -- paulus
1324 */
1325 restore_altstack(&ctx->uc_stack);
1326
1327 set_thread_flag(TIF_RESTOREALL);
1328 out:
1329 return 0;
1330}
1331#endif
1332
1333/*
1334 * OK, we're invoking a handler
1335 */
1336int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
1337 struct task_struct *tsk)
1338{
1339 struct sigcontext __user *sc;
1340 struct sigframe __user *frame;
1341 struct mcontext __user *tm_mctx = NULL;
1342 unsigned long newsp = 0;
1343 int sigret;
1344 unsigned long tramp;
1345 struct pt_regs *regs = tsk->thread.regs;
1346
1347 BUG_ON(tsk != current);
1348
1349 /* Set up Signal Frame */
1350 frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
1351 if (unlikely(frame == NULL))
1352 goto badframe;
1353 sc = (struct sigcontext __user *) &frame->sctx;
1354
1355#if _NSIG != 64
1356#error "Please adjust handle_signal()"
1357#endif
1358 if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
1359 || __put_user(oldset->sig[0], &sc->oldmask)
1360#ifdef CONFIG_PPC64
1361 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1362#else
1363 || __put_user(oldset->sig[1], &sc->_unused[3])
1364#endif
1365 || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1366 || __put_user(ksig->sig, &sc->signal))
1367 goto badframe;
1368
1369 if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
1370 sigret = 0;
1371 tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
1372 } else {
1373 sigret = __NR_sigreturn;
1374 tramp = (unsigned long) frame->mctx.tramp;
1375 }
1376
1377#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1378 tm_mctx = &frame->mctx_transact;
1379 if (MSR_TM_ACTIVE(regs->msr)) {
1380 if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
1381 sigret))
1382 goto badframe;
1383 }
1384 else
1385#endif
1386 {
1387 if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
1388 goto badframe;
1389 }
1390
1391 regs->link = tramp;
1392
1393 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
1394
1395 /* create a stack frame for the caller of the handler */
1396 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1397 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1398 goto badframe;
1399
1400 regs->gpr[1] = newsp;
1401 regs->gpr[3] = ksig->sig;
1402 regs->gpr[4] = (unsigned long) sc;
1403 regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
1404 /* enter the signal handler in big-endian mode */
1405 regs->msr &= ~MSR_LE;
1406 return 0;
1407
1408badframe:
1409 if (show_unhandled_signals)
1410 printk_ratelimited(KERN_INFO
1411 "%s[%d]: bad frame in handle_signal32: "
1412 "%p nip %08lx lr %08lx\n",
1413 tsk->comm, tsk->pid,
1414 frame, regs->nip, regs->link);
1415
1416 return 1;
1417}
1418
1419/*
1420 * Do a signal return; undo the signal stack.
1421 */
1422long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1423 struct pt_regs *regs)
1424{
1425 struct sigframe __user *sf;
1426 struct sigcontext __user *sc;
1427 struct sigcontext sigctx;
1428 struct mcontext __user *sr;
1429 void __user *addr;
1430 sigset_t set;
1431#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1432 struct mcontext __user *mcp, *tm_mcp;
1433 unsigned long msr_hi;
1434#endif
1435
1436 /* Always make any pending restarted system calls return -EINTR */
1437 current->restart_block.fn = do_no_restart_syscall;
1438
1439 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1440 sc = &sf->sctx;
1441 addr = sc;
1442 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1443 goto badframe;
1444
1445#ifdef CONFIG_PPC64
1446 /*
1447 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1448 * unused part of the signal stackframe
1449 */
1450 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1451#else
1452 set.sig[0] = sigctx.oldmask;
1453 set.sig[1] = sigctx._unused[3];
1454#endif
1455 set_current_blocked(&set);
1456
1457#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1458 mcp = (struct mcontext __user *)&sf->mctx;
1459 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1460 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1461 goto badframe;
1462 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1463 if (!cpu_has_feature(CPU_FTR_TM))
1464 goto badframe;
1465 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1466 goto badframe;
1467 } else
1468#endif
1469 {
1470 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1471 addr = sr;
1472 if (!access_ok(VERIFY_READ, sr, sizeof(*sr))
1473 || restore_user_regs(regs, sr, 1))
1474 goto badframe;
1475 }
1476
1477 set_thread_flag(TIF_RESTOREALL);
1478 return 0;
1479
1480badframe:
1481 if (show_unhandled_signals)
1482 printk_ratelimited(KERN_INFO
1483 "%s[%d]: bad frame in sys_sigreturn: "
1484 "%p nip %08lx lr %08lx\n",
1485 current->comm, current->pid,
1486 addr, regs->nip, regs->link);
1487
1488 force_sig(SIGSEGV, current);
1489 return 0;
1490}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
4 *
5 * PowerPC version
6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
7 * Copyright (C) 2001 IBM
8 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
9 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
10 *
11 * Derived from "arch/i386/kernel/signal.c"
12 * Copyright (C) 1991, 1992 Linus Torvalds
13 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
14 */
15
16#include <linux/sched.h>
17#include <linux/mm.h>
18#include <linux/smp.h>
19#include <linux/kernel.h>
20#include <linux/signal.h>
21#include <linux/errno.h>
22#include <linux/elf.h>
23#include <linux/ptrace.h>
24#include <linux/pagemap.h>
25#include <linux/ratelimit.h>
26#include <linux/syscalls.h>
27#ifdef CONFIG_PPC64
28#include <linux/compat.h>
29#else
30#include <linux/wait.h>
31#include <linux/unistd.h>
32#include <linux/stddef.h>
33#include <linux/tty.h>
34#include <linux/binfmts.h>
35#endif
36
37#include <linux/uaccess.h>
38#include <asm/cacheflush.h>
39#include <asm/syscalls.h>
40#include <asm/sigcontext.h>
41#include <asm/vdso.h>
42#include <asm/switch_to.h>
43#include <asm/tm.h>
44#include <asm/asm-prototypes.h>
45#ifdef CONFIG_PPC64
46#include <asm/syscalls_32.h>
47#include <asm/unistd.h>
48#else
49#include <asm/ucontext.h>
50#endif
51
52#include "signal.h"
53
54
55#ifdef CONFIG_PPC64
56#define old_sigaction old_sigaction32
57#define sigcontext sigcontext32
58#define mcontext mcontext32
59#define ucontext ucontext32
60
61/*
62 * Userspace code may pass a ucontext which doesn't include VSX added
63 * at the end. We need to check for this case.
64 */
65#define UCONTEXTSIZEWITHOUTVSX \
66 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
67
68/*
69 * Returning 0 means we return to userspace via
70 * ret_from_except and thus restore all user
71 * registers from *regs. This is what we need
72 * to do when a signal has been delivered.
73 */
74
75#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
76#undef __SIGNAL_FRAMESIZE
77#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
78#undef ELF_NVRREG
79#define ELF_NVRREG ELF_NVRREG32
80
81/*
82 * Functions for flipping sigsets (thanks to brain dead generic
83 * implementation that makes things simple for little endian only)
84 */
85#define unsafe_put_sigset_t unsafe_put_compat_sigset
86#define unsafe_get_sigset_t unsafe_get_compat_sigset
87
88#define to_user_ptr(p) ptr_to_compat(p)
89#define from_user_ptr(p) compat_ptr(p)
90
91static __always_inline int
92__unsafe_save_general_regs(struct pt_regs *regs, struct mcontext __user *frame)
93{
94 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
95 int val, i;
96
97 for (i = 0; i <= PT_RESULT; i ++) {
98 /* Force usr to alway see softe as 1 (interrupts enabled) */
99 if (i == PT_SOFTE)
100 val = 1;
101 else
102 val = gregs[i];
103
104 unsafe_put_user(val, &frame->mc_gregs[i], failed);
105 }
106 return 0;
107
108failed:
109 return 1;
110}
111
112static __always_inline int
113__unsafe_restore_general_regs(struct pt_regs *regs, struct mcontext __user *sr)
114{
115 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
116 int i;
117
118 for (i = 0; i <= PT_RESULT; i++) {
119 if ((i == PT_MSR) || (i == PT_SOFTE))
120 continue;
121 unsafe_get_user(gregs[i], &sr->mc_gregs[i], failed);
122 }
123 return 0;
124
125failed:
126 return 1;
127}
128
129#else /* CONFIG_PPC64 */
130
131#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
132
133#define unsafe_put_sigset_t(uset, set, label) do { \
134 sigset_t __user *__us = uset ; \
135 const sigset_t *__s = set; \
136 \
137 unsafe_copy_to_user(__us, __s, sizeof(*__us), label); \
138} while (0)
139
140#define unsafe_get_sigset_t unsafe_get_user_sigset
141
142#define to_user_ptr(p) ((unsigned long)(p))
143#define from_user_ptr(p) ((void __user *)(p))
144
145static __always_inline int
146__unsafe_save_general_regs(struct pt_regs *regs, struct mcontext __user *frame)
147{
148 unsafe_copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE, failed);
149 return 0;
150
151failed:
152 return 1;
153}
154
155static __always_inline
156int __unsafe_restore_general_regs(struct pt_regs *regs, struct mcontext __user *sr)
157{
158 /* copy up to but not including MSR */
159 unsafe_copy_from_user(regs, &sr->mc_gregs, PT_MSR * sizeof(elf_greg_t), failed);
160
161 /* copy from orig_r3 (the word after the MSR) up to the end */
162 unsafe_copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
163 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t), failed);
164
165 return 0;
166
167failed:
168 return 1;
169}
170#endif
171
172#define unsafe_save_general_regs(regs, frame, label) do { \
173 if (__unsafe_save_general_regs(regs, frame)) \
174 goto label; \
175} while (0)
176
177#define unsafe_restore_general_regs(regs, frame, label) do { \
178 if (__unsafe_restore_general_regs(regs, frame)) \
179 goto label; \
180} while (0)
181
182/*
183 * When we have signals to deliver, we set up on the
184 * user stack, going down from the original stack pointer:
185 * an ABI gap of 56 words
186 * an mcontext struct
187 * a sigcontext struct
188 * a gap of __SIGNAL_FRAMESIZE bytes
189 *
190 * Each of these things must be a multiple of 16 bytes in size. The following
191 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
192 *
193 */
194struct sigframe {
195 struct sigcontext sctx; /* the sigcontext */
196 struct mcontext mctx; /* all the register values */
197#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
198 struct sigcontext sctx_transact;
199 struct mcontext mctx_transact;
200#endif
201 /*
202 * Programs using the rs6000/xcoff abi can save up to 19 gp
203 * regs and 18 fp regs below sp before decrementing it.
204 */
205 int abigap[56];
206};
207
208/*
209 * When we have rt signals to deliver, we set up on the
210 * user stack, going down from the original stack pointer:
211 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
212 * a gap of __SIGNAL_FRAMESIZE+16 bytes
213 * (the +16 is to get the siginfo and ucontext in the same
214 * positions as in older kernels).
215 *
216 * Each of these things must be a multiple of 16 bytes in size.
217 *
218 */
219struct rt_sigframe {
220#ifdef CONFIG_PPC64
221 compat_siginfo_t info;
222#else
223 struct siginfo info;
224#endif
225 struct ucontext uc;
226#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
227 struct ucontext uc_transact;
228#endif
229 /*
230 * Programs using the rs6000/xcoff abi can save up to 19 gp
231 * regs and 18 fp regs below sp before decrementing it.
232 */
233 int abigap[56];
234};
235
236unsigned long get_min_sigframe_size_32(void)
237{
238 return max(sizeof(struct rt_sigframe) + __SIGNAL_FRAMESIZE + 16,
239 sizeof(struct sigframe) + __SIGNAL_FRAMESIZE);
240}
241
242/*
243 * Save the current user registers on the user stack.
244 * We only save the altivec/spe registers if the process has used
245 * altivec/spe instructions at some point.
246 */
247static void prepare_save_user_regs(int ctx_has_vsx_region)
248{
249 /* Make sure floating point registers are stored in regs */
250 flush_fp_to_thread(current);
251#ifdef CONFIG_ALTIVEC
252 if (current->thread.used_vr)
253 flush_altivec_to_thread(current);
254 if (cpu_has_feature(CPU_FTR_ALTIVEC))
255 current->thread.vrsave = mfspr(SPRN_VRSAVE);
256#endif
257#ifdef CONFIG_VSX
258 if (current->thread.used_vsr && ctx_has_vsx_region)
259 flush_vsx_to_thread(current);
260#endif
261#ifdef CONFIG_SPE
262 if (current->thread.used_spe)
263 flush_spe_to_thread(current);
264#endif
265}
266
267static __always_inline int
268__unsafe_save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
269 struct mcontext __user *tm_frame, int ctx_has_vsx_region)
270{
271 unsigned long msr = regs->msr;
272
273 /* save general registers */
274 unsafe_save_general_regs(regs, frame, failed);
275
276#ifdef CONFIG_ALTIVEC
277 /* save altivec registers */
278 if (current->thread.used_vr) {
279 unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
280 ELF_NVRREG * sizeof(vector128), failed);
281 /* set MSR_VEC in the saved MSR value to indicate that
282 frame->mc_vregs contains valid data */
283 msr |= MSR_VEC;
284 }
285 /* else assert((regs->msr & MSR_VEC) == 0) */
286
287 /* We always copy to/from vrsave, it's 0 if we don't have or don't
288 * use altivec. Since VSCR only contains 32 bits saved in the least
289 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
290 * most significant bits of that same vector. --BenH
291 * Note that the current VRSAVE value is in the SPR at this point.
292 */
293 unsafe_put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32],
294 failed);
295#endif /* CONFIG_ALTIVEC */
296 unsafe_copy_fpr_to_user(&frame->mc_fregs, current, failed);
297
298 /*
299 * Clear the MSR VSX bit to indicate there is no valid state attached
300 * to this context, except in the specific case below where we set it.
301 */
302 msr &= ~MSR_VSX;
303#ifdef CONFIG_VSX
304 /*
305 * Copy VSR 0-31 upper half from thread_struct to local
306 * buffer, then write that to userspace. Also set MSR_VSX in
307 * the saved MSR value to indicate that frame->mc_vregs
308 * contains valid data
309 */
310 if (current->thread.used_vsr && ctx_has_vsx_region) {
311 unsafe_copy_vsx_to_user(&frame->mc_vsregs, current, failed);
312 msr |= MSR_VSX;
313 }
314#endif /* CONFIG_VSX */
315#ifdef CONFIG_SPE
316 /* save spe registers */
317 if (current->thread.used_spe) {
318 unsafe_copy_to_user(&frame->mc_vregs, current->thread.evr,
319 ELF_NEVRREG * sizeof(u32), failed);
320 /* set MSR_SPE in the saved MSR value to indicate that
321 frame->mc_vregs contains valid data */
322 msr |= MSR_SPE;
323 }
324 /* else assert((regs->msr & MSR_SPE) == 0) */
325
326 /* We always copy to/from spefscr */
327 unsafe_put_user(current->thread.spefscr,
328 (u32 __user *)&frame->mc_vregs + ELF_NEVRREG, failed);
329#endif /* CONFIG_SPE */
330
331 unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
332
333 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
334 * can check it on the restore to see if TM is active
335 */
336 if (tm_frame)
337 unsafe_put_user(0, &tm_frame->mc_gregs[PT_MSR], failed);
338
339 return 0;
340
341failed:
342 return 1;
343}
344
345#define unsafe_save_user_regs(regs, frame, tm_frame, has_vsx, label) do { \
346 if (__unsafe_save_user_regs(regs, frame, tm_frame, has_vsx)) \
347 goto label; \
348} while (0)
349
350#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
351/*
352 * Save the current user registers on the user stack.
353 * We only save the altivec/spe registers if the process has used
354 * altivec/spe instructions at some point.
355 * We also save the transactional registers to a second ucontext in the
356 * frame.
357 *
358 * See __unsafe_save_user_regs() and signal_64.c:setup_tm_sigcontexts().
359 */
360static void prepare_save_tm_user_regs(void)
361{
362 WARN_ON(tm_suspend_disabled);
363
364 if (cpu_has_feature(CPU_FTR_ALTIVEC))
365 current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
366}
367
368static __always_inline int
369save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
370 struct mcontext __user *tm_frame, unsigned long msr)
371{
372 /* Save both sets of general registers */
373 unsafe_save_general_regs(¤t->thread.ckpt_regs, frame, failed);
374 unsafe_save_general_regs(regs, tm_frame, failed);
375
376 /* Stash the top half of the 64bit MSR into the 32bit MSR word
377 * of the transactional mcontext. This way we have a backward-compatible
378 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
379 * also look at what type of transaction (T or S) was active at the
380 * time of the signal.
381 */
382 unsafe_put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR], failed);
383
384 /* save altivec registers */
385 if (current->thread.used_vr) {
386 unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
387 ELF_NVRREG * sizeof(vector128), failed);
388 if (msr & MSR_VEC)
389 unsafe_copy_to_user(&tm_frame->mc_vregs,
390 ¤t->thread.vr_state,
391 ELF_NVRREG * sizeof(vector128), failed);
392 else
393 unsafe_copy_to_user(&tm_frame->mc_vregs,
394 ¤t->thread.ckvr_state,
395 ELF_NVRREG * sizeof(vector128), failed);
396
397 /* set MSR_VEC in the saved MSR value to indicate that
398 * frame->mc_vregs contains valid data
399 */
400 msr |= MSR_VEC;
401 }
402
403 /* We always copy to/from vrsave, it's 0 if we don't have or don't
404 * use altivec. Since VSCR only contains 32 bits saved in the least
405 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
406 * most significant bits of that same vector. --BenH
407 */
408 unsafe_put_user(current->thread.ckvrsave,
409 (u32 __user *)&frame->mc_vregs[32], failed);
410 if (msr & MSR_VEC)
411 unsafe_put_user(current->thread.vrsave,
412 (u32 __user *)&tm_frame->mc_vregs[32], failed);
413 else
414 unsafe_put_user(current->thread.ckvrsave,
415 (u32 __user *)&tm_frame->mc_vregs[32], failed);
416
417 unsafe_copy_ckfpr_to_user(&frame->mc_fregs, current, failed);
418 if (msr & MSR_FP)
419 unsafe_copy_fpr_to_user(&tm_frame->mc_fregs, current, failed);
420 else
421 unsafe_copy_ckfpr_to_user(&tm_frame->mc_fregs, current, failed);
422
423 /*
424 * Copy VSR 0-31 upper half from thread_struct to local
425 * buffer, then write that to userspace. Also set MSR_VSX in
426 * the saved MSR value to indicate that frame->mc_vregs
427 * contains valid data
428 */
429 if (current->thread.used_vsr) {
430 unsafe_copy_ckvsx_to_user(&frame->mc_vsregs, current, failed);
431 if (msr & MSR_VSX)
432 unsafe_copy_vsx_to_user(&tm_frame->mc_vsregs, current, failed);
433 else
434 unsafe_copy_ckvsx_to_user(&tm_frame->mc_vsregs, current, failed);
435
436 msr |= MSR_VSX;
437 }
438
439 unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
440
441 return 0;
442
443failed:
444 return 1;
445}
446#else
447static void prepare_save_tm_user_regs(void) { }
448
449static __always_inline int
450save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
451 struct mcontext __user *tm_frame, unsigned long msr)
452{
453 return 0;
454}
455#endif
456
457#define unsafe_save_tm_user_regs(regs, frame, tm_frame, msr, label) do { \
458 if (save_tm_user_regs_unsafe(regs, frame, tm_frame, msr)) \
459 goto label; \
460} while (0)
461
462/*
463 * Restore the current user register values from the user stack,
464 * (except for MSR).
465 */
466static long restore_user_regs(struct pt_regs *regs,
467 struct mcontext __user *sr, int sig)
468{
469 unsigned int save_r2 = 0;
470 unsigned long msr;
471#ifdef CONFIG_VSX
472 int i;
473#endif
474
475 if (!user_read_access_begin(sr, sizeof(*sr)))
476 return 1;
477 /*
478 * restore general registers but not including MSR or SOFTE. Also
479 * take care of keeping r2 (TLS) intact if not a signal
480 */
481 if (!sig)
482 save_r2 = (unsigned int)regs->gpr[2];
483 unsafe_restore_general_regs(regs, sr, failed);
484 set_trap_norestart(regs);
485 unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed);
486 if (!sig)
487 regs->gpr[2] = (unsigned long) save_r2;
488
489 /* if doing signal return, restore the previous little-endian mode */
490 if (sig)
491 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (msr & MSR_LE));
492
493#ifdef CONFIG_ALTIVEC
494 /*
495 * Force the process to reload the altivec registers from
496 * current->thread when it next does altivec instructions
497 */
498 regs_set_return_msr(regs, regs->msr & ~MSR_VEC);
499 if (msr & MSR_VEC) {
500 /* restore altivec registers from the stack */
501 unsafe_copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
502 sizeof(sr->mc_vregs), failed);
503 current->thread.used_vr = true;
504 } else if (current->thread.used_vr)
505 memset(¤t->thread.vr_state, 0,
506 ELF_NVRREG * sizeof(vector128));
507
508 /* Always get VRSAVE back */
509 unsafe_get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32], failed);
510 if (cpu_has_feature(CPU_FTR_ALTIVEC))
511 mtspr(SPRN_VRSAVE, current->thread.vrsave);
512#endif /* CONFIG_ALTIVEC */
513 unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed);
514
515#ifdef CONFIG_VSX
516 /*
517 * Force the process to reload the VSX registers from
518 * current->thread when it next does VSX instruction.
519 */
520 regs_set_return_msr(regs, regs->msr & ~MSR_VSX);
521 if (msr & MSR_VSX) {
522 /*
523 * Restore altivec registers from the stack to a local
524 * buffer, then write this out to the thread_struct
525 */
526 unsafe_copy_vsx_from_user(current, &sr->mc_vsregs, failed);
527 current->thread.used_vsr = true;
528 } else if (current->thread.used_vsr)
529 for (i = 0; i < 32 ; i++)
530 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
531#endif /* CONFIG_VSX */
532 /*
533 * force the process to reload the FP registers from
534 * current->thread when it next does FP instructions
535 */
536 regs_set_return_msr(regs, regs->msr & ~(MSR_FP | MSR_FE0 | MSR_FE1));
537
538#ifdef CONFIG_SPE
539 /*
540 * Force the process to reload the spe registers from
541 * current->thread when it next does spe instructions.
542 * Since this is user ABI, we must enforce the sizing.
543 */
544 BUILD_BUG_ON(sizeof(current->thread.spe) != ELF_NEVRREG * sizeof(u32));
545 regs_set_return_msr(regs, regs->msr & ~MSR_SPE);
546 if (msr & MSR_SPE) {
547 /* restore spe registers from the stack */
548 unsafe_copy_from_user(¤t->thread.spe, &sr->mc_vregs,
549 sizeof(current->thread.spe), failed);
550 current->thread.used_spe = true;
551 } else if (current->thread.used_spe)
552 memset(¤t->thread.spe, 0, sizeof(current->thread.spe));
553
554 /* Always get SPEFSCR back */
555 unsafe_get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG, failed);
556#endif /* CONFIG_SPE */
557
558 user_read_access_end();
559 return 0;
560
561failed:
562 user_read_access_end();
563 return 1;
564}
565
566#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
567/*
568 * Restore the current user register values from the user stack, except for
569 * MSR, and recheckpoint the original checkpointed register state for processes
570 * in transactions.
571 */
572static long restore_tm_user_regs(struct pt_regs *regs,
573 struct mcontext __user *sr,
574 struct mcontext __user *tm_sr)
575{
576 unsigned long msr, msr_hi;
577 int i;
578
579 if (tm_suspend_disabled)
580 return 1;
581 /*
582 * restore general registers but not including MSR or SOFTE. Also
583 * take care of keeping r2 (TLS) intact if not a signal.
584 * See comment in signal_64.c:restore_tm_sigcontexts();
585 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
586 * were set by the signal delivery.
587 */
588 if (!user_read_access_begin(sr, sizeof(*sr)))
589 return 1;
590
591 unsafe_restore_general_regs(¤t->thread.ckpt_regs, sr, failed);
592 unsafe_get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP], failed);
593 unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed);
594
595 /* Restore the previous little-endian mode */
596 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (msr & MSR_LE));
597
598 regs_set_return_msr(regs, regs->msr & ~MSR_VEC);
599 if (msr & MSR_VEC) {
600 /* restore altivec registers from the stack */
601 unsafe_copy_from_user(¤t->thread.ckvr_state, &sr->mc_vregs,
602 sizeof(sr->mc_vregs), failed);
603 current->thread.used_vr = true;
604 } else if (current->thread.used_vr) {
605 memset(¤t->thread.vr_state, 0,
606 ELF_NVRREG * sizeof(vector128));
607 memset(¤t->thread.ckvr_state, 0,
608 ELF_NVRREG * sizeof(vector128));
609 }
610
611 /* Always get VRSAVE back */
612 unsafe_get_user(current->thread.ckvrsave,
613 (u32 __user *)&sr->mc_vregs[32], failed);
614 if (cpu_has_feature(CPU_FTR_ALTIVEC))
615 mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
616
617 regs_set_return_msr(regs, regs->msr & ~(MSR_FP | MSR_FE0 | MSR_FE1));
618
619 unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed);
620
621 regs_set_return_msr(regs, regs->msr & ~MSR_VSX);
622 if (msr & MSR_VSX) {
623 /*
624 * Restore altivec registers from the stack to a local
625 * buffer, then write this out to the thread_struct
626 */
627 unsafe_copy_ckvsx_from_user(current, &sr->mc_vsregs, failed);
628 current->thread.used_vsr = true;
629 } else if (current->thread.used_vsr)
630 for (i = 0; i < 32 ; i++) {
631 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
632 current->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
633 }
634
635 user_read_access_end();
636
637 if (!user_read_access_begin(tm_sr, sizeof(*tm_sr)))
638 return 1;
639
640 unsafe_restore_general_regs(regs, tm_sr, failed);
641
642 /* restore altivec registers from the stack */
643 if (msr & MSR_VEC)
644 unsafe_copy_from_user(¤t->thread.vr_state, &tm_sr->mc_vregs,
645 sizeof(sr->mc_vregs), failed);
646
647 /* Always get VRSAVE back */
648 unsafe_get_user(current->thread.vrsave,
649 (u32 __user *)&tm_sr->mc_vregs[32], failed);
650
651 unsafe_copy_ckfpr_from_user(current, &tm_sr->mc_fregs, failed);
652
653 if (msr & MSR_VSX) {
654 /*
655 * Restore altivec registers from the stack to a local
656 * buffer, then write this out to the thread_struct
657 */
658 unsafe_copy_vsx_from_user(current, &tm_sr->mc_vsregs, failed);
659 current->thread.used_vsr = true;
660 }
661
662 /* Get the top half of the MSR from the user context */
663 unsafe_get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR], failed);
664 msr_hi <<= 32;
665
666 user_read_access_end();
667
668 /* If TM bits are set to the reserved value, it's an invalid context */
669 if (MSR_TM_RESV(msr_hi))
670 return 1;
671
672 /*
673 * Disabling preemption, since it is unsafe to be preempted
674 * with MSR[TS] set without recheckpointing.
675 */
676 preempt_disable();
677
678 /*
679 * CAUTION:
680 * After regs->MSR[TS] being updated, make sure that get_user(),
681 * put_user() or similar functions are *not* called. These
682 * functions can generate page faults which will cause the process
683 * to be de-scheduled with MSR[TS] set but without calling
684 * tm_recheckpoint(). This can cause a bug.
685 *
686 * Pull in the MSR TM bits from the user context
687 */
688 regs_set_return_msr(regs, (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK));
689 /* Now, recheckpoint. This loads up all of the checkpointed (older)
690 * registers, including FP and V[S]Rs. After recheckpointing, the
691 * transactional versions should be loaded.
692 */
693 tm_enable();
694 /* Make sure the transaction is marked as failed */
695 current->thread.tm_texasr |= TEXASR_FS;
696 /* This loads the checkpointed FP/VEC state, if used */
697 tm_recheckpoint(¤t->thread);
698
699 /* This loads the speculative FP/VEC state, if used */
700 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
701 if (msr & MSR_FP) {
702 load_fp_state(¤t->thread.fp_state);
703 regs_set_return_msr(regs, regs->msr | (MSR_FP | current->thread.fpexc_mode));
704 }
705 if (msr & MSR_VEC) {
706 load_vr_state(¤t->thread.vr_state);
707 regs_set_return_msr(regs, regs->msr | MSR_VEC);
708 }
709
710 preempt_enable();
711
712 return 0;
713
714failed:
715 user_read_access_end();
716 return 1;
717}
718#else
719static long restore_tm_user_regs(struct pt_regs *regs, struct mcontext __user *sr,
720 struct mcontext __user *tm_sr)
721{
722 return 0;
723}
724#endif
725
726#ifdef CONFIG_PPC64
727
728#define copy_siginfo_to_user copy_siginfo_to_user32
729
730#endif /* CONFIG_PPC64 */
731
732/*
733 * Set up a signal frame for a "real-time" signal handler
734 * (one which gets siginfo).
735 */
736int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
737 struct task_struct *tsk)
738{
739 struct rt_sigframe __user *frame;
740 struct mcontext __user *mctx;
741 struct mcontext __user *tm_mctx = NULL;
742 unsigned long newsp = 0;
743 unsigned long tramp;
744 struct pt_regs *regs = tsk->thread.regs;
745 /* Save the thread's msr before get_tm_stackpointer() changes it */
746 unsigned long msr = regs->msr;
747
748 /* Set up Signal Frame */
749 frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
750 mctx = &frame->uc.uc_mcontext;
751#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
752 tm_mctx = &frame->uc_transact.uc_mcontext;
753#endif
754 if (MSR_TM_ACTIVE(msr))
755 prepare_save_tm_user_regs();
756 else
757 prepare_save_user_regs(1);
758
759 if (!user_access_begin(frame, sizeof(*frame)))
760 goto badframe;
761
762 /* Put the siginfo & fill in most of the ucontext */
763 unsafe_put_user(0, &frame->uc.uc_flags, failed);
764#ifdef CONFIG_PPC64
765 unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->gpr[1], failed);
766#else
767 unsafe_save_altstack(&frame->uc.uc_stack, regs->gpr[1], failed);
768#endif
769 unsafe_put_user(to_user_ptr(&frame->uc.uc_mcontext), &frame->uc.uc_regs, failed);
770
771 if (MSR_TM_ACTIVE(msr)) {
772#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
773 unsafe_put_user((unsigned long)&frame->uc_transact,
774 &frame->uc.uc_link, failed);
775 unsafe_put_user((unsigned long)tm_mctx,
776 &frame->uc_transact.uc_regs, failed);
777#endif
778 unsafe_save_tm_user_regs(regs, mctx, tm_mctx, msr, failed);
779 } else {
780 unsafe_put_user(0, &frame->uc.uc_link, failed);
781 unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
782 }
783
784 /* Save user registers on the stack */
785 if (tsk->mm->context.vdso) {
786 tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp_rt32);
787 } else {
788 tramp = (unsigned long)mctx->mc_pad;
789 unsafe_put_user(PPC_RAW_LI(_R0, __NR_rt_sigreturn), &mctx->mc_pad[0], failed);
790 unsafe_put_user(PPC_RAW_SC(), &mctx->mc_pad[1], failed);
791 asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0]));
792 }
793 unsafe_put_sigset_t(&frame->uc.uc_sigmask, oldset, failed);
794
795 user_access_end();
796
797 if (copy_siginfo_to_user(&frame->info, &ksig->info))
798 goto badframe;
799
800 regs->link = tramp;
801
802#ifdef CONFIG_PPC_FPU_REGS
803 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
804#endif
805
806 /* create a stack frame for the caller of the handler */
807 newsp = ((unsigned long)frame) - (__SIGNAL_FRAMESIZE + 16);
808 if (put_user(regs->gpr[1], (u32 __user *)newsp))
809 goto badframe;
810
811 /* Fill registers for signal handler */
812 regs->gpr[1] = newsp;
813 regs->gpr[3] = ksig->sig;
814 regs->gpr[4] = (unsigned long)&frame->info;
815 regs->gpr[5] = (unsigned long)&frame->uc;
816 regs->gpr[6] = (unsigned long)frame;
817 regs_set_return_ip(regs, (unsigned long) ksig->ka.sa.sa_handler);
818 /* enter the signal handler in native-endian mode */
819 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (MSR_KERNEL & MSR_LE));
820
821 return 0;
822
823failed:
824 user_access_end();
825
826badframe:
827 signal_fault(tsk, regs, "handle_rt_signal32", frame);
828
829 return 1;
830}
831
832/*
833 * OK, we're invoking a handler
834 */
835int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
836 struct task_struct *tsk)
837{
838 struct sigcontext __user *sc;
839 struct sigframe __user *frame;
840 struct mcontext __user *mctx;
841 struct mcontext __user *tm_mctx = NULL;
842 unsigned long newsp = 0;
843 unsigned long tramp;
844 struct pt_regs *regs = tsk->thread.regs;
845 /* Save the thread's msr before get_tm_stackpointer() changes it */
846 unsigned long msr = regs->msr;
847
848 /* Set up Signal Frame */
849 frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
850 mctx = &frame->mctx;
851#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
852 tm_mctx = &frame->mctx_transact;
853#endif
854 if (MSR_TM_ACTIVE(msr))
855 prepare_save_tm_user_regs();
856 else
857 prepare_save_user_regs(1);
858
859 if (!user_access_begin(frame, sizeof(*frame)))
860 goto badframe;
861 sc = (struct sigcontext __user *) &frame->sctx;
862
863#if _NSIG != 64
864#error "Please adjust handle_signal()"
865#endif
866 unsafe_put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler, failed);
867 unsafe_put_user(oldset->sig[0], &sc->oldmask, failed);
868#ifdef CONFIG_PPC64
869 unsafe_put_user((oldset->sig[0] >> 32), &sc->_unused[3], failed);
870#else
871 unsafe_put_user(oldset->sig[1], &sc->_unused[3], failed);
872#endif
873 unsafe_put_user(to_user_ptr(mctx), &sc->regs, failed);
874 unsafe_put_user(ksig->sig, &sc->signal, failed);
875
876 if (MSR_TM_ACTIVE(msr))
877 unsafe_save_tm_user_regs(regs, mctx, tm_mctx, msr, failed);
878 else
879 unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
880
881 if (tsk->mm->context.vdso) {
882 tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp32);
883 } else {
884 tramp = (unsigned long)mctx->mc_pad;
885 unsafe_put_user(PPC_RAW_LI(_R0, __NR_sigreturn), &mctx->mc_pad[0], failed);
886 unsafe_put_user(PPC_RAW_SC(), &mctx->mc_pad[1], failed);
887 asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0]));
888 }
889 user_access_end();
890
891 regs->link = tramp;
892
893#ifdef CONFIG_PPC_FPU_REGS
894 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
895#endif
896
897 /* create a stack frame for the caller of the handler */
898 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
899 if (put_user(regs->gpr[1], (u32 __user *)newsp))
900 goto badframe;
901
902 regs->gpr[1] = newsp;
903 regs->gpr[3] = ksig->sig;
904 regs->gpr[4] = (unsigned long) sc;
905 regs_set_return_ip(regs, (unsigned long) ksig->ka.sa.sa_handler);
906 /* enter the signal handler in native-endian mode */
907 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (MSR_KERNEL & MSR_LE));
908
909 return 0;
910
911failed:
912 user_access_end();
913
914badframe:
915 signal_fault(tsk, regs, "handle_signal32", frame);
916
917 return 1;
918}
919
920static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
921{
922 sigset_t set;
923 struct mcontext __user *mcp;
924
925 if (!user_read_access_begin(ucp, sizeof(*ucp)))
926 return -EFAULT;
927
928 unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
929#ifdef CONFIG_PPC64
930 {
931 u32 cmcp;
932
933 unsafe_get_user(cmcp, &ucp->uc_regs, failed);
934 mcp = (struct mcontext __user *)(u64)cmcp;
935 }
936#else
937 unsafe_get_user(mcp, &ucp->uc_regs, failed);
938#endif
939 user_read_access_end();
940
941 set_current_blocked(&set);
942 if (restore_user_regs(regs, mcp, sig))
943 return -EFAULT;
944
945 return 0;
946
947failed:
948 user_read_access_end();
949 return -EFAULT;
950}
951
952#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
953static int do_setcontext_tm(struct ucontext __user *ucp,
954 struct ucontext __user *tm_ucp,
955 struct pt_regs *regs)
956{
957 sigset_t set;
958 struct mcontext __user *mcp;
959 struct mcontext __user *tm_mcp;
960 u32 cmcp;
961 u32 tm_cmcp;
962
963 if (!user_read_access_begin(ucp, sizeof(*ucp)))
964 return -EFAULT;
965
966 unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
967 unsafe_get_user(cmcp, &ucp->uc_regs, failed);
968
969 user_read_access_end();
970
971 if (__get_user(tm_cmcp, &tm_ucp->uc_regs))
972 return -EFAULT;
973 mcp = (struct mcontext __user *)(u64)cmcp;
974 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
975 /* no need to check access_ok(mcp), since mcp < 4GB */
976
977 set_current_blocked(&set);
978 if (restore_tm_user_regs(regs, mcp, tm_mcp))
979 return -EFAULT;
980
981 return 0;
982
983failed:
984 user_read_access_end();
985 return -EFAULT;
986}
987#endif
988
989#ifdef CONFIG_PPC64
990COMPAT_SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
991 struct ucontext __user *, new_ctx, int, ctx_size)
992#else
993SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
994 struct ucontext __user *, new_ctx, long, ctx_size)
995#endif
996{
997 struct pt_regs *regs = current_pt_regs();
998 int ctx_has_vsx_region = 0;
999
1000#ifdef CONFIG_PPC64
1001 unsigned long new_msr = 0;
1002
1003 if (new_ctx) {
1004 struct mcontext __user *mcp;
1005 u32 cmcp;
1006
1007 /*
1008 * Get pointer to the real mcontext. No need for
1009 * access_ok since we are dealing with compat
1010 * pointers.
1011 */
1012 if (__get_user(cmcp, &new_ctx->uc_regs))
1013 return -EFAULT;
1014 mcp = (struct mcontext __user *)(u64)cmcp;
1015 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
1016 return -EFAULT;
1017 }
1018 /*
1019 * Check that the context is not smaller than the original
1020 * size (with VMX but without VSX)
1021 */
1022 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
1023 return -EINVAL;
1024 /*
1025 * If the new context state sets the MSR VSX bits but
1026 * it doesn't provide VSX state.
1027 */
1028 if ((ctx_size < sizeof(struct ucontext)) &&
1029 (new_msr & MSR_VSX))
1030 return -EINVAL;
1031 /* Does the context have enough room to store VSX data? */
1032 if (ctx_size >= sizeof(struct ucontext))
1033 ctx_has_vsx_region = 1;
1034#else
1035 /* Context size is for future use. Right now, we only make sure
1036 * we are passed something we understand
1037 */
1038 if (ctx_size < sizeof(struct ucontext))
1039 return -EINVAL;
1040#endif
1041 if (old_ctx != NULL) {
1042 struct mcontext __user *mctx;
1043
1044 /*
1045 * old_ctx might not be 16-byte aligned, in which
1046 * case old_ctx->uc_mcontext won't be either.
1047 * Because we have the old_ctx->uc_pad2 field
1048 * before old_ctx->uc_mcontext, we need to round down
1049 * from &old_ctx->uc_mcontext to a 16-byte boundary.
1050 */
1051 mctx = (struct mcontext __user *)
1052 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
1053 prepare_save_user_regs(ctx_has_vsx_region);
1054 if (!user_write_access_begin(old_ctx, ctx_size))
1055 return -EFAULT;
1056 unsafe_save_user_regs(regs, mctx, NULL, ctx_has_vsx_region, failed);
1057 unsafe_put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked, failed);
1058 unsafe_put_user(to_user_ptr(mctx), &old_ctx->uc_regs, failed);
1059 user_write_access_end();
1060 }
1061 if (new_ctx == NULL)
1062 return 0;
1063 if (!access_ok(new_ctx, ctx_size) ||
1064 fault_in_readable((char __user *)new_ctx, ctx_size))
1065 return -EFAULT;
1066
1067 /*
1068 * If we get a fault copying the context into the kernel's
1069 * image of the user's registers, we can't just return -EFAULT
1070 * because the user's registers will be corrupted. For instance
1071 * the NIP value may have been updated but not some of the
1072 * other registers. Given that we have done the access_ok
1073 * and successfully read the first and last bytes of the region
1074 * above, this should only happen in an out-of-memory situation
1075 * or if another thread unmaps the region containing the context.
1076 * We kill the task with a SIGSEGV in this situation.
1077 */
1078 if (do_setcontext(new_ctx, regs, 0)) {
1079 force_exit_sig(SIGSEGV);
1080 return -EFAULT;
1081 }
1082
1083 set_thread_flag(TIF_RESTOREALL);
1084 return 0;
1085
1086failed:
1087 user_write_access_end();
1088 return -EFAULT;
1089}
1090
1091#ifdef CONFIG_PPC64
1092COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
1093#else
1094SYSCALL_DEFINE0(rt_sigreturn)
1095#endif
1096{
1097 struct rt_sigframe __user *rt_sf;
1098 struct pt_regs *regs = current_pt_regs();
1099 int tm_restore = 0;
1100#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1101 struct ucontext __user *uc_transact;
1102 unsigned long msr_hi;
1103 unsigned long tmp;
1104#endif
1105 /* Always make any pending restarted system calls return -EINTR */
1106 current->restart_block.fn = do_no_restart_syscall;
1107
1108 rt_sf = (struct rt_sigframe __user *)
1109 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1110 if (!access_ok(rt_sf, sizeof(*rt_sf)))
1111 goto bad;
1112
1113#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1114 /*
1115 * If there is a transactional state then throw it away.
1116 * The purpose of a sigreturn is to destroy all traces of the
1117 * signal frame, this includes any transactional state created
1118 * within in. We only check for suspended as we can never be
1119 * active in the kernel, we are active, there is nothing better to
1120 * do than go ahead and Bad Thing later.
1121 * The cause is not important as there will never be a
1122 * recheckpoint so it's not user visible.
1123 */
1124 if (MSR_TM_SUSPENDED(mfmsr()))
1125 tm_reclaim_current(0);
1126
1127 if (__get_user(tmp, &rt_sf->uc.uc_link))
1128 goto bad;
1129 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1130 if (uc_transact) {
1131 u32 cmcp;
1132 struct mcontext __user *mcp;
1133
1134 if (__get_user(cmcp, &uc_transact->uc_regs))
1135 return -EFAULT;
1136 mcp = (struct mcontext __user *)(u64)cmcp;
1137 /* The top 32 bits of the MSR are stashed in the transactional
1138 * ucontext. */
1139 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1140 goto bad;
1141
1142 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1143 /* Trying to start TM on non TM system */
1144 if (!cpu_has_feature(CPU_FTR_TM))
1145 goto bad;
1146 /* We only recheckpoint on return if we're
1147 * transaction.
1148 */
1149 tm_restore = 1;
1150 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1151 goto bad;
1152 }
1153 }
1154 if (!tm_restore) {
1155 /*
1156 * Unset regs->msr because ucontext MSR TS is not
1157 * set, and recheckpoint was not called. This avoid
1158 * hitting a TM Bad thing at RFID
1159 */
1160 regs_set_return_msr(regs, regs->msr & ~MSR_TS_MASK);
1161 }
1162 /* Fall through, for non-TM restore */
1163#endif
1164 if (!tm_restore)
1165 if (do_setcontext(&rt_sf->uc, regs, 1))
1166 goto bad;
1167
1168 /*
1169 * It's not clear whether or why it is desirable to save the
1170 * sigaltstack setting on signal delivery and restore it on
1171 * signal return. But other architectures do this and we have
1172 * always done it up until now so it is probably better not to
1173 * change it. -- paulus
1174 */
1175#ifdef CONFIG_PPC64
1176 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1177 goto bad;
1178#else
1179 if (restore_altstack(&rt_sf->uc.uc_stack))
1180 goto bad;
1181#endif
1182 set_thread_flag(TIF_RESTOREALL);
1183 return 0;
1184
1185 bad:
1186 signal_fault(current, regs, "sys_rt_sigreturn", rt_sf);
1187
1188 force_sig(SIGSEGV);
1189 return 0;
1190}
1191
1192#ifdef CONFIG_PPC32
1193SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
1194 int, ndbg, struct sig_dbg_op __user *, dbg)
1195{
1196 struct pt_regs *regs = current_pt_regs();
1197 struct sig_dbg_op op;
1198 int i;
1199 unsigned long new_msr = regs->msr;
1200#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1201 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1202#endif
1203
1204 for (i=0; i<ndbg; i++) {
1205 if (copy_from_user(&op, dbg + i, sizeof(op)))
1206 return -EFAULT;
1207 switch (op.dbg_type) {
1208 case SIG_DBG_SINGLE_STEPPING:
1209#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1210 if (op.dbg_value) {
1211 new_msr |= MSR_DE;
1212 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1213 } else {
1214 new_dbcr0 &= ~DBCR0_IC;
1215 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1216 current->thread.debug.dbcr1)) {
1217 new_msr &= ~MSR_DE;
1218 new_dbcr0 &= ~DBCR0_IDM;
1219 }
1220 }
1221#else
1222 if (op.dbg_value)
1223 new_msr |= MSR_SE;
1224 else
1225 new_msr &= ~MSR_SE;
1226#endif
1227 break;
1228 case SIG_DBG_BRANCH_TRACING:
1229#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1230 return -EINVAL;
1231#else
1232 if (op.dbg_value)
1233 new_msr |= MSR_BE;
1234 else
1235 new_msr &= ~MSR_BE;
1236#endif
1237 break;
1238
1239 default:
1240 return -EINVAL;
1241 }
1242 }
1243
1244 /* We wait until here to actually install the values in the
1245 registers so if we fail in the above loop, it will not
1246 affect the contents of these registers. After this point,
1247 failure is a problem, anyway, and it's very unlikely unless
1248 the user is really doing something wrong. */
1249 regs_set_return_msr(regs, new_msr);
1250#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1251 current->thread.debug.dbcr0 = new_dbcr0;
1252#endif
1253
1254 if (!access_ok(ctx, sizeof(*ctx)) ||
1255 fault_in_readable((char __user *)ctx, sizeof(*ctx)))
1256 return -EFAULT;
1257
1258 /*
1259 * If we get a fault copying the context into the kernel's
1260 * image of the user's registers, we can't just return -EFAULT
1261 * because the user's registers will be corrupted. For instance
1262 * the NIP value may have been updated but not some of the
1263 * other registers. Given that we have done the access_ok
1264 * and successfully read the first and last bytes of the region
1265 * above, this should only happen in an out-of-memory situation
1266 * or if another thread unmaps the region containing the context.
1267 * We kill the task with a SIGSEGV in this situation.
1268 */
1269 if (do_setcontext(ctx, regs, 1)) {
1270 signal_fault(current, regs, "sys_debug_setcontext", ctx);
1271
1272 force_sig(SIGSEGV);
1273 goto out;
1274 }
1275
1276 /*
1277 * It's not clear whether or why it is desirable to save the
1278 * sigaltstack setting on signal delivery and restore it on
1279 * signal return. But other architectures do this and we have
1280 * always done it up until now so it is probably better not to
1281 * change it. -- paulus
1282 */
1283 restore_altstack(&ctx->uc_stack);
1284
1285 set_thread_flag(TIF_RESTOREALL);
1286 out:
1287 return 0;
1288}
1289#endif
1290
1291/*
1292 * Do a signal return; undo the signal stack.
1293 */
1294#ifdef CONFIG_PPC64
1295COMPAT_SYSCALL_DEFINE0(sigreturn)
1296#else
1297SYSCALL_DEFINE0(sigreturn)
1298#endif
1299{
1300 struct pt_regs *regs = current_pt_regs();
1301 struct sigframe __user *sf;
1302 struct sigcontext __user *sc;
1303 struct sigcontext sigctx;
1304 struct mcontext __user *sr;
1305 sigset_t set;
1306 struct mcontext __user *mcp;
1307 struct mcontext __user *tm_mcp = NULL;
1308 unsigned long long msr_hi = 0;
1309
1310 /* Always make any pending restarted system calls return -EINTR */
1311 current->restart_block.fn = do_no_restart_syscall;
1312
1313 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1314 sc = &sf->sctx;
1315 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1316 goto badframe;
1317
1318#ifdef CONFIG_PPC64
1319 /*
1320 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1321 * unused part of the signal stackframe
1322 */
1323 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1324#else
1325 set.sig[0] = sigctx.oldmask;
1326 set.sig[1] = sigctx._unused[3];
1327#endif
1328 set_current_blocked(&set);
1329
1330 mcp = (struct mcontext __user *)&sf->mctx;
1331#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1332 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1333 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1334 goto badframe;
1335#endif
1336 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1337 if (!cpu_has_feature(CPU_FTR_TM))
1338 goto badframe;
1339 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1340 goto badframe;
1341 } else {
1342 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1343 if (restore_user_regs(regs, sr, 1)) {
1344 signal_fault(current, regs, "sys_sigreturn", sr);
1345
1346 force_sig(SIGSEGV);
1347 return 0;
1348 }
1349 }
1350
1351 set_thread_flag(TIF_RESTOREALL);
1352 return 0;
1353
1354badframe:
1355 signal_fault(current, regs, "sys_sigreturn", sc);
1356
1357 force_sig(SIGSEGV);
1358 return 0;
1359}