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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 "ppc32.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#define __save_altstack __compat_save_altstack
62
63/*
64 * Userspace code may pass a ucontext which doesn't include VSX added
65 * at the end. We need to check for this case.
66 */
67#define UCONTEXTSIZEWITHOUTVSX \
68 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
69
70/*
71 * Returning 0 means we return to userspace via
72 * ret_from_except and thus restore all user
73 * registers from *regs. This is what we need
74 * to do when a signal has been delivered.
75 */
76
77#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
78#undef __SIGNAL_FRAMESIZE
79#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
80#undef ELF_NVRREG
81#define ELF_NVRREG ELF_NVRREG32
82
83/*
84 * Functions for flipping sigsets (thanks to brain dead generic
85 * implementation that makes things simple for little endian only)
86 */
87static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
88{
89 return put_compat_sigset(uset, set, sizeof(*uset));
90}
91
92static inline int get_sigset_t(sigset_t *set,
93 const compat_sigset_t __user *uset)
94{
95 return get_compat_sigset(set, uset);
96}
97
98#define to_user_ptr(p) ptr_to_compat(p)
99#define from_user_ptr(p) compat_ptr(p)
100
101static inline int save_general_regs(struct pt_regs *regs,
102 struct mcontext __user *frame)
103{
104 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
105 int val, i;
106
107 WARN_ON(!FULL_REGS(regs));
108
109 for (i = 0; i <= PT_RESULT; i ++) {
110 /* Force usr to alway see softe as 1 (interrupts enabled) */
111 if (i == PT_SOFTE)
112 val = 1;
113 else
114 val = gregs[i];
115
116 if (__put_user(val, &frame->mc_gregs[i]))
117 return -EFAULT;
118 }
119 return 0;
120}
121
122static inline int restore_general_regs(struct pt_regs *regs,
123 struct mcontext __user *sr)
124{
125 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
126 int i;
127
128 for (i = 0; i <= PT_RESULT; i++) {
129 if ((i == PT_MSR) || (i == PT_SOFTE))
130 continue;
131 if (__get_user(gregs[i], &sr->mc_gregs[i]))
132 return -EFAULT;
133 }
134 return 0;
135}
136
137#else /* CONFIG_PPC64 */
138
139#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
140
141static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
142{
143 return copy_to_user(uset, set, sizeof(*uset));
144}
145
146static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
147{
148 return copy_from_user(set, uset, sizeof(*uset));
149}
150
151#define to_user_ptr(p) ((unsigned long)(p))
152#define from_user_ptr(p) ((void __user *)(p))
153
154static inline int save_general_regs(struct pt_regs *regs,
155 struct mcontext __user *frame)
156{
157 WARN_ON(!FULL_REGS(regs));
158 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
159}
160
161static inline int restore_general_regs(struct pt_regs *regs,
162 struct mcontext __user *sr)
163{
164 /* copy up to but not including MSR */
165 if (__copy_from_user(regs, &sr->mc_gregs,
166 PT_MSR * sizeof(elf_greg_t)))
167 return -EFAULT;
168 /* copy from orig_r3 (the word after the MSR) up to the end */
169 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
170 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
171 return -EFAULT;
172 return 0;
173}
174#endif
175
176/*
177 * When we have signals to deliver, we set up on the
178 * user stack, going down from the original stack pointer:
179 * an ABI gap of 56 words
180 * an mcontext struct
181 * a sigcontext struct
182 * a gap of __SIGNAL_FRAMESIZE bytes
183 *
184 * Each of these things must be a multiple of 16 bytes in size. The following
185 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
186 *
187 */
188struct sigframe {
189 struct sigcontext sctx; /* the sigcontext */
190 struct mcontext mctx; /* all the register values */
191#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
192 struct sigcontext sctx_transact;
193 struct mcontext mctx_transact;
194#endif
195 /*
196 * Programs using the rs6000/xcoff abi can save up to 19 gp
197 * regs and 18 fp regs below sp before decrementing it.
198 */
199 int abigap[56];
200};
201
202/* We use the mc_pad field for the signal return trampoline. */
203#define tramp mc_pad
204
205/*
206 * When we have rt signals to deliver, we set up on the
207 * user stack, going down from the original stack pointer:
208 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
209 * a gap of __SIGNAL_FRAMESIZE+16 bytes
210 * (the +16 is to get the siginfo and ucontext in the same
211 * positions as in older kernels).
212 *
213 * Each of these things must be a multiple of 16 bytes in size.
214 *
215 */
216struct rt_sigframe {
217#ifdef CONFIG_PPC64
218 compat_siginfo_t info;
219#else
220 struct siginfo info;
221#endif
222 struct ucontext uc;
223#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
224 struct ucontext uc_transact;
225#endif
226 /*
227 * Programs using the rs6000/xcoff abi can save up to 19 gp
228 * regs and 18 fp regs below sp before decrementing it.
229 */
230 int abigap[56];
231};
232
233/*
234 * Save the current user registers on the user stack.
235 * We only save the altivec/spe registers if the process has used
236 * altivec/spe instructions at some point.
237 */
238static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
239 struct mcontext __user *tm_frame, int sigret,
240 int ctx_has_vsx_region)
241{
242 unsigned long msr = regs->msr;
243
244 /* Make sure floating point registers are stored in regs */
245 flush_fp_to_thread(current);
246
247 /* save general registers */
248 if (save_general_regs(regs, frame))
249 return 1;
250
251#ifdef CONFIG_ALTIVEC
252 /* save altivec registers */
253 if (current->thread.used_vr) {
254 flush_altivec_to_thread(current);
255 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
256 ELF_NVRREG * sizeof(vector128)))
257 return 1;
258 /* set MSR_VEC in the saved MSR value to indicate that
259 frame->mc_vregs contains valid data */
260 msr |= MSR_VEC;
261 }
262 /* else assert((regs->msr & MSR_VEC) == 0) */
263
264 /* We always copy to/from vrsave, it's 0 if we don't have or don't
265 * use altivec. Since VSCR only contains 32 bits saved in the least
266 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
267 * most significant bits of that same vector. --BenH
268 * Note that the current VRSAVE value is in the SPR at this point.
269 */
270 if (cpu_has_feature(CPU_FTR_ALTIVEC))
271 current->thread.vrsave = mfspr(SPRN_VRSAVE);
272 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
273 return 1;
274#endif /* CONFIG_ALTIVEC */
275 if (copy_fpr_to_user(&frame->mc_fregs, current))
276 return 1;
277
278 /*
279 * Clear the MSR VSX bit to indicate there is no valid state attached
280 * to this context, except in the specific case below where we set it.
281 */
282 msr &= ~MSR_VSX;
283#ifdef CONFIG_VSX
284 /*
285 * Copy VSR 0-31 upper half from thread_struct to local
286 * buffer, then write that to userspace. Also set MSR_VSX in
287 * the saved MSR value to indicate that frame->mc_vregs
288 * contains valid data
289 */
290 if (current->thread.used_vsr && ctx_has_vsx_region) {
291 flush_vsx_to_thread(current);
292 if (copy_vsx_to_user(&frame->mc_vsregs, current))
293 return 1;
294 msr |= MSR_VSX;
295 }
296#endif /* CONFIG_VSX */
297#ifdef CONFIG_SPE
298 /* save spe registers */
299 if (current->thread.used_spe) {
300 flush_spe_to_thread(current);
301 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
302 ELF_NEVRREG * sizeof(u32)))
303 return 1;
304 /* set MSR_SPE in the saved MSR value to indicate that
305 frame->mc_vregs contains valid data */
306 msr |= MSR_SPE;
307 }
308 /* else assert((regs->msr & MSR_SPE) == 0) */
309
310 /* We always copy to/from spefscr */
311 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
312 return 1;
313#endif /* CONFIG_SPE */
314
315 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
316 return 1;
317 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
318 * can check it on the restore to see if TM is active
319 */
320 if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
321 return 1;
322
323 if (sigret) {
324 /* Set up the sigreturn trampoline: li 0,sigret; sc */
325 if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
326 || __put_user(PPC_INST_SC, &frame->tramp[1]))
327 return 1;
328 flush_icache_range((unsigned long) &frame->tramp[0],
329 (unsigned long) &frame->tramp[2]);
330 }
331
332 return 0;
333}
334
335#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
336/*
337 * Save the current user registers on the user stack.
338 * We only save the altivec/spe registers if the process has used
339 * altivec/spe instructions at some point.
340 * We also save the transactional registers to a second ucontext in the
341 * frame.
342 *
343 * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
344 */
345static int save_tm_user_regs(struct pt_regs *regs,
346 struct mcontext __user *frame,
347 struct mcontext __user *tm_frame, int sigret,
348 unsigned long msr)
349{
350 WARN_ON(tm_suspend_disabled);
351
352 /* Save both sets of general registers */
353 if (save_general_regs(¤t->thread.ckpt_regs, frame)
354 || save_general_regs(regs, tm_frame))
355 return 1;
356
357 /* Stash the top half of the 64bit MSR into the 32bit MSR word
358 * of the transactional mcontext. This way we have a backward-compatible
359 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
360 * also look at what type of transaction (T or S) was active at the
361 * time of the signal.
362 */
363 if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
364 return 1;
365
366#ifdef CONFIG_ALTIVEC
367 /* save altivec registers */
368 if (current->thread.used_vr) {
369 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
370 ELF_NVRREG * sizeof(vector128)))
371 return 1;
372 if (msr & MSR_VEC) {
373 if (__copy_to_user(&tm_frame->mc_vregs,
374 ¤t->thread.vr_state,
375 ELF_NVRREG * sizeof(vector128)))
376 return 1;
377 } else {
378 if (__copy_to_user(&tm_frame->mc_vregs,
379 ¤t->thread.ckvr_state,
380 ELF_NVRREG * sizeof(vector128)))
381 return 1;
382 }
383
384 /* set MSR_VEC in the saved MSR value to indicate that
385 * frame->mc_vregs contains valid data
386 */
387 msr |= MSR_VEC;
388 }
389
390 /* We always copy to/from vrsave, it's 0 if we don't have or don't
391 * use altivec. Since VSCR only contains 32 bits saved in the least
392 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
393 * most significant bits of that same vector. --BenH
394 */
395 if (cpu_has_feature(CPU_FTR_ALTIVEC))
396 current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
397 if (__put_user(current->thread.ckvrsave,
398 (u32 __user *)&frame->mc_vregs[32]))
399 return 1;
400 if (msr & MSR_VEC) {
401 if (__put_user(current->thread.vrsave,
402 (u32 __user *)&tm_frame->mc_vregs[32]))
403 return 1;
404 } else {
405 if (__put_user(current->thread.ckvrsave,
406 (u32 __user *)&tm_frame->mc_vregs[32]))
407 return 1;
408 }
409#endif /* CONFIG_ALTIVEC */
410
411 if (copy_ckfpr_to_user(&frame->mc_fregs, current))
412 return 1;
413 if (msr & MSR_FP) {
414 if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
415 return 1;
416 } else {
417 if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
418 return 1;
419 }
420
421#ifdef CONFIG_VSX
422 /*
423 * Copy VSR 0-31 upper half from thread_struct to local
424 * buffer, then write that to userspace. Also set MSR_VSX in
425 * the saved MSR value to indicate that frame->mc_vregs
426 * contains valid data
427 */
428 if (current->thread.used_vsr) {
429 if (copy_ckvsx_to_user(&frame->mc_vsregs, current))
430 return 1;
431 if (msr & MSR_VSX) {
432 if (copy_vsx_to_user(&tm_frame->mc_vsregs,
433 current))
434 return 1;
435 } else {
436 if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
437 return 1;
438 }
439
440 msr |= MSR_VSX;
441 }
442#endif /* CONFIG_VSX */
443#ifdef CONFIG_SPE
444 /* SPE regs are not checkpointed with TM, so this section is
445 * simply the same as in save_user_regs().
446 */
447 if (current->thread.used_spe) {
448 flush_spe_to_thread(current);
449 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
450 ELF_NEVRREG * sizeof(u32)))
451 return 1;
452 /* set MSR_SPE in the saved MSR value to indicate that
453 * frame->mc_vregs contains valid data */
454 msr |= MSR_SPE;
455 }
456
457 /* We always copy to/from spefscr */
458 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
459 return 1;
460#endif /* CONFIG_SPE */
461
462 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
463 return 1;
464 if (sigret) {
465 /* Set up the sigreturn trampoline: li 0,sigret; sc */
466 if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
467 || __put_user(PPC_INST_SC, &frame->tramp[1]))
468 return 1;
469 flush_icache_range((unsigned long) &frame->tramp[0],
470 (unsigned long) &frame->tramp[2]);
471 }
472
473 return 0;
474}
475#endif
476
477/*
478 * Restore the current user register values from the user stack,
479 * (except for MSR).
480 */
481static long restore_user_regs(struct pt_regs *regs,
482 struct mcontext __user *sr, int sig)
483{
484 long err;
485 unsigned int save_r2 = 0;
486 unsigned long msr;
487#ifdef CONFIG_VSX
488 int i;
489#endif
490
491 /*
492 * restore general registers but not including MSR or SOFTE. Also
493 * take care of keeping r2 (TLS) intact if not a signal
494 */
495 if (!sig)
496 save_r2 = (unsigned int)regs->gpr[2];
497 err = restore_general_regs(regs, sr);
498 set_trap_norestart(regs);
499 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
500 if (!sig)
501 regs->gpr[2] = (unsigned long) save_r2;
502 if (err)
503 return 1;
504
505 /* if doing signal return, restore the previous little-endian mode */
506 if (sig)
507 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
508
509#ifdef CONFIG_ALTIVEC
510 /*
511 * Force the process to reload the altivec registers from
512 * current->thread when it next does altivec instructions
513 */
514 regs->msr &= ~MSR_VEC;
515 if (msr & MSR_VEC) {
516 /* restore altivec registers from the stack */
517 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
518 sizeof(sr->mc_vregs)))
519 return 1;
520 current->thread.used_vr = true;
521 } else if (current->thread.used_vr)
522 memset(¤t->thread.vr_state, 0,
523 ELF_NVRREG * sizeof(vector128));
524
525 /* Always get VRSAVE back */
526 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
527 return 1;
528 if (cpu_has_feature(CPU_FTR_ALTIVEC))
529 mtspr(SPRN_VRSAVE, current->thread.vrsave);
530#endif /* CONFIG_ALTIVEC */
531 if (copy_fpr_from_user(current, &sr->mc_fregs))
532 return 1;
533
534#ifdef CONFIG_VSX
535 /*
536 * Force the process to reload the VSX registers from
537 * current->thread when it next does VSX instruction.
538 */
539 regs->msr &= ~MSR_VSX;
540 if (msr & MSR_VSX) {
541 /*
542 * Restore altivec registers from the stack to a local
543 * buffer, then write this out to the thread_struct
544 */
545 if (copy_vsx_from_user(current, &sr->mc_vsregs))
546 return 1;
547 current->thread.used_vsr = true;
548 } else if (current->thread.used_vsr)
549 for (i = 0; i < 32 ; i++)
550 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
551#endif /* CONFIG_VSX */
552 /*
553 * force the process to reload the FP registers from
554 * current->thread when it next does FP instructions
555 */
556 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
557
558#ifdef CONFIG_SPE
559 /* force the process to reload the spe registers from
560 current->thread when it next does spe instructions */
561 regs->msr &= ~MSR_SPE;
562 if (msr & MSR_SPE) {
563 /* restore spe registers from the stack */
564 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
565 ELF_NEVRREG * sizeof(u32)))
566 return 1;
567 current->thread.used_spe = true;
568 } else if (current->thread.used_spe)
569 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
570
571 /* Always get SPEFSCR back */
572 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
573 return 1;
574#endif /* CONFIG_SPE */
575
576 return 0;
577}
578
579#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
580/*
581 * Restore the current user register values from the user stack, except for
582 * MSR, and recheckpoint the original checkpointed register state for processes
583 * in transactions.
584 */
585static long restore_tm_user_regs(struct pt_regs *regs,
586 struct mcontext __user *sr,
587 struct mcontext __user *tm_sr)
588{
589 long err;
590 unsigned long msr, msr_hi;
591#ifdef CONFIG_VSX
592 int i;
593#endif
594
595 if (tm_suspend_disabled)
596 return 1;
597 /*
598 * restore general registers but not including MSR or SOFTE. Also
599 * take care of keeping r2 (TLS) intact if not a signal.
600 * See comment in signal_64.c:restore_tm_sigcontexts();
601 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
602 * were set by the signal delivery.
603 */
604 err = restore_general_regs(regs, tm_sr);
605 err |= restore_general_regs(¤t->thread.ckpt_regs, sr);
606
607 err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
608
609 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
610 if (err)
611 return 1;
612
613 /* Restore the previous little-endian mode */
614 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
615
616#ifdef CONFIG_ALTIVEC
617 regs->msr &= ~MSR_VEC;
618 if (msr & MSR_VEC) {
619 /* restore altivec registers from the stack */
620 if (__copy_from_user(¤t->thread.ckvr_state, &sr->mc_vregs,
621 sizeof(sr->mc_vregs)) ||
622 __copy_from_user(¤t->thread.vr_state,
623 &tm_sr->mc_vregs,
624 sizeof(sr->mc_vregs)))
625 return 1;
626 current->thread.used_vr = true;
627 } else if (current->thread.used_vr) {
628 memset(¤t->thread.vr_state, 0,
629 ELF_NVRREG * sizeof(vector128));
630 memset(¤t->thread.ckvr_state, 0,
631 ELF_NVRREG * sizeof(vector128));
632 }
633
634 /* Always get VRSAVE back */
635 if (__get_user(current->thread.ckvrsave,
636 (u32 __user *)&sr->mc_vregs[32]) ||
637 __get_user(current->thread.vrsave,
638 (u32 __user *)&tm_sr->mc_vregs[32]))
639 return 1;
640 if (cpu_has_feature(CPU_FTR_ALTIVEC))
641 mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
642#endif /* CONFIG_ALTIVEC */
643
644 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
645
646 if (copy_fpr_from_user(current, &sr->mc_fregs) ||
647 copy_ckfpr_from_user(current, &tm_sr->mc_fregs))
648 return 1;
649
650#ifdef CONFIG_VSX
651 regs->msr &= ~MSR_VSX;
652 if (msr & MSR_VSX) {
653 /*
654 * Restore altivec registers from the stack to a local
655 * buffer, then write this out to the thread_struct
656 */
657 if (copy_vsx_from_user(current, &tm_sr->mc_vsregs) ||
658 copy_ckvsx_from_user(current, &sr->mc_vsregs))
659 return 1;
660 current->thread.used_vsr = true;
661 } else if (current->thread.used_vsr)
662 for (i = 0; i < 32 ; i++) {
663 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
664 current->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
665 }
666#endif /* CONFIG_VSX */
667
668#ifdef CONFIG_SPE
669 /* SPE regs are not checkpointed with TM, so this section is
670 * simply the same as in restore_user_regs().
671 */
672 regs->msr &= ~MSR_SPE;
673 if (msr & MSR_SPE) {
674 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
675 ELF_NEVRREG * sizeof(u32)))
676 return 1;
677 current->thread.used_spe = true;
678 } else if (current->thread.used_spe)
679 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
680
681 /* Always get SPEFSCR back */
682 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
683 + ELF_NEVRREG))
684 return 1;
685#endif /* CONFIG_SPE */
686
687 /* Get the top half of the MSR from the user context */
688 if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
689 return 1;
690 msr_hi <<= 32;
691 /* If TM bits are set to the reserved value, it's an invalid context */
692 if (MSR_TM_RESV(msr_hi))
693 return 1;
694
695 /*
696 * Disabling preemption, since it is unsafe to be preempted
697 * with MSR[TS] set without recheckpointing.
698 */
699 preempt_disable();
700
701 /*
702 * CAUTION:
703 * After regs->MSR[TS] being updated, make sure that get_user(),
704 * put_user() or similar functions are *not* called. These
705 * functions can generate page faults which will cause the process
706 * to be de-scheduled with MSR[TS] set but without calling
707 * tm_recheckpoint(). This can cause a bug.
708 *
709 * Pull in the MSR TM bits from the user context
710 */
711 regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK);
712 /* Now, recheckpoint. This loads up all of the checkpointed (older)
713 * registers, including FP and V[S]Rs. After recheckpointing, the
714 * transactional versions should be loaded.
715 */
716 tm_enable();
717 /* Make sure the transaction is marked as failed */
718 current->thread.tm_texasr |= TEXASR_FS;
719 /* This loads the checkpointed FP/VEC state, if used */
720 tm_recheckpoint(¤t->thread);
721
722 /* This loads the speculative FP/VEC state, if used */
723 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
724 if (msr & MSR_FP) {
725 load_fp_state(¤t->thread.fp_state);
726 regs->msr |= (MSR_FP | current->thread.fpexc_mode);
727 }
728#ifdef CONFIG_ALTIVEC
729 if (msr & MSR_VEC) {
730 load_vr_state(¤t->thread.vr_state);
731 regs->msr |= MSR_VEC;
732 }
733#endif
734
735 preempt_enable();
736
737 return 0;
738}
739#endif
740
741#ifdef CONFIG_PPC64
742
743#define copy_siginfo_to_user copy_siginfo_to_user32
744
745#endif /* CONFIG_PPC64 */
746
747/*
748 * Set up a signal frame for a "real-time" signal handler
749 * (one which gets siginfo).
750 */
751int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
752 struct task_struct *tsk)
753{
754 struct rt_sigframe __user *rt_sf;
755 struct mcontext __user *frame;
756 struct mcontext __user *tm_frame = NULL;
757 void __user *addr;
758 unsigned long newsp = 0;
759 int sigret;
760 unsigned long tramp;
761 struct pt_regs *regs = tsk->thread.regs;
762#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
763 /* Save the thread's msr before get_tm_stackpointer() changes it */
764 unsigned long msr = regs->msr;
765#endif
766
767 BUG_ON(tsk != current);
768
769 /* Set up Signal Frame */
770 /* Put a Real Time Context onto stack */
771 rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
772 addr = rt_sf;
773 if (unlikely(rt_sf == NULL))
774 goto badframe;
775
776 /* Put the siginfo & fill in most of the ucontext */
777 if (copy_siginfo_to_user(&rt_sf->info, &ksig->info)
778 || __put_user(0, &rt_sf->uc.uc_flags)
779 || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
780 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
781 &rt_sf->uc.uc_regs)
782 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
783 goto badframe;
784
785 /* Save user registers on the stack */
786 frame = &rt_sf->uc.uc_mcontext;
787 addr = frame;
788 if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
789 sigret = 0;
790 tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
791 } else {
792 sigret = __NR_rt_sigreturn;
793 tramp = (unsigned long) frame->tramp;
794 }
795
796#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
797 tm_frame = &rt_sf->uc_transact.uc_mcontext;
798 if (MSR_TM_ACTIVE(msr)) {
799 if (__put_user((unsigned long)&rt_sf->uc_transact,
800 &rt_sf->uc.uc_link) ||
801 __put_user((unsigned long)tm_frame,
802 &rt_sf->uc_transact.uc_regs))
803 goto badframe;
804 if (save_tm_user_regs(regs, frame, tm_frame, sigret, msr))
805 goto badframe;
806 }
807 else
808#endif
809 {
810 if (__put_user(0, &rt_sf->uc.uc_link))
811 goto badframe;
812 if (save_user_regs(regs, frame, tm_frame, sigret, 1))
813 goto badframe;
814 }
815 regs->link = tramp;
816
817 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
818
819 /* create a stack frame for the caller of the handler */
820 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
821 addr = (void __user *)regs->gpr[1];
822 if (put_user(regs->gpr[1], (u32 __user *)newsp))
823 goto badframe;
824
825 /* Fill registers for signal handler */
826 regs->gpr[1] = newsp;
827 regs->gpr[3] = ksig->sig;
828 regs->gpr[4] = (unsigned long) &rt_sf->info;
829 regs->gpr[5] = (unsigned long) &rt_sf->uc;
830 regs->gpr[6] = (unsigned long) rt_sf;
831 regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
832 /* enter the signal handler in native-endian mode */
833 regs->msr &= ~MSR_LE;
834 regs->msr |= (MSR_KERNEL & MSR_LE);
835 return 0;
836
837badframe:
838 if (show_unhandled_signals)
839 printk_ratelimited(KERN_INFO
840 "%s[%d]: bad frame in handle_rt_signal32: "
841 "%p nip %08lx lr %08lx\n",
842 tsk->comm, tsk->pid,
843 addr, regs->nip, regs->link);
844
845 return 1;
846}
847
848static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
849{
850 sigset_t set;
851 struct mcontext __user *mcp;
852
853 if (get_sigset_t(&set, &ucp->uc_sigmask))
854 return -EFAULT;
855#ifdef CONFIG_PPC64
856 {
857 u32 cmcp;
858
859 if (__get_user(cmcp, &ucp->uc_regs))
860 return -EFAULT;
861 mcp = (struct mcontext __user *)(u64)cmcp;
862 /* no need to check access_ok(mcp), since mcp < 4GB */
863 }
864#else
865 if (__get_user(mcp, &ucp->uc_regs))
866 return -EFAULT;
867 if (!access_ok(mcp, sizeof(*mcp)))
868 return -EFAULT;
869#endif
870 set_current_blocked(&set);
871 if (restore_user_regs(regs, mcp, sig))
872 return -EFAULT;
873
874 return 0;
875}
876
877#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
878static int do_setcontext_tm(struct ucontext __user *ucp,
879 struct ucontext __user *tm_ucp,
880 struct pt_regs *regs)
881{
882 sigset_t set;
883 struct mcontext __user *mcp;
884 struct mcontext __user *tm_mcp;
885 u32 cmcp;
886 u32 tm_cmcp;
887
888 if (get_sigset_t(&set, &ucp->uc_sigmask))
889 return -EFAULT;
890
891 if (__get_user(cmcp, &ucp->uc_regs) ||
892 __get_user(tm_cmcp, &tm_ucp->uc_regs))
893 return -EFAULT;
894 mcp = (struct mcontext __user *)(u64)cmcp;
895 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
896 /* no need to check access_ok(mcp), since mcp < 4GB */
897
898 set_current_blocked(&set);
899 if (restore_tm_user_regs(regs, mcp, tm_mcp))
900 return -EFAULT;
901
902 return 0;
903}
904#endif
905
906#ifdef CONFIG_PPC64
907COMPAT_SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
908 struct ucontext __user *, new_ctx, int, ctx_size)
909#else
910SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
911 struct ucontext __user *, new_ctx, long, ctx_size)
912#endif
913{
914 struct pt_regs *regs = current_pt_regs();
915 int ctx_has_vsx_region = 0;
916
917#ifdef CONFIG_PPC64
918 unsigned long new_msr = 0;
919
920 if (new_ctx) {
921 struct mcontext __user *mcp;
922 u32 cmcp;
923
924 /*
925 * Get pointer to the real mcontext. No need for
926 * access_ok since we are dealing with compat
927 * pointers.
928 */
929 if (__get_user(cmcp, &new_ctx->uc_regs))
930 return -EFAULT;
931 mcp = (struct mcontext __user *)(u64)cmcp;
932 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
933 return -EFAULT;
934 }
935 /*
936 * Check that the context is not smaller than the original
937 * size (with VMX but without VSX)
938 */
939 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
940 return -EINVAL;
941 /*
942 * If the new context state sets the MSR VSX bits but
943 * it doesn't provide VSX state.
944 */
945 if ((ctx_size < sizeof(struct ucontext)) &&
946 (new_msr & MSR_VSX))
947 return -EINVAL;
948 /* Does the context have enough room to store VSX data? */
949 if (ctx_size >= sizeof(struct ucontext))
950 ctx_has_vsx_region = 1;
951#else
952 /* Context size is for future use. Right now, we only make sure
953 * we are passed something we understand
954 */
955 if (ctx_size < sizeof(struct ucontext))
956 return -EINVAL;
957#endif
958 if (old_ctx != NULL) {
959 struct mcontext __user *mctx;
960
961 /*
962 * old_ctx might not be 16-byte aligned, in which
963 * case old_ctx->uc_mcontext won't be either.
964 * Because we have the old_ctx->uc_pad2 field
965 * before old_ctx->uc_mcontext, we need to round down
966 * from &old_ctx->uc_mcontext to a 16-byte boundary.
967 */
968 mctx = (struct mcontext __user *)
969 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
970 if (!access_ok(old_ctx, ctx_size)
971 || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
972 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
973 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
974 return -EFAULT;
975 }
976 if (new_ctx == NULL)
977 return 0;
978 if (!access_ok(new_ctx, ctx_size) ||
979 fault_in_pages_readable((u8 __user *)new_ctx, ctx_size))
980 return -EFAULT;
981
982 /*
983 * If we get a fault copying the context into the kernel's
984 * image of the user's registers, we can't just return -EFAULT
985 * because the user's registers will be corrupted. For instance
986 * the NIP value may have been updated but not some of the
987 * other registers. Given that we have done the access_ok
988 * and successfully read the first and last bytes of the region
989 * above, this should only happen in an out-of-memory situation
990 * or if another thread unmaps the region containing the context.
991 * We kill the task with a SIGSEGV in this situation.
992 */
993 if (do_setcontext(new_ctx, regs, 0))
994 do_exit(SIGSEGV);
995
996 set_thread_flag(TIF_RESTOREALL);
997 return 0;
998}
999
1000#ifdef CONFIG_PPC64
1001COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
1002#else
1003SYSCALL_DEFINE0(rt_sigreturn)
1004#endif
1005{
1006 struct rt_sigframe __user *rt_sf;
1007 struct pt_regs *regs = current_pt_regs();
1008 int tm_restore = 0;
1009#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1010 struct ucontext __user *uc_transact;
1011 unsigned long msr_hi;
1012 unsigned long tmp;
1013#endif
1014 /* Always make any pending restarted system calls return -EINTR */
1015 current->restart_block.fn = do_no_restart_syscall;
1016
1017 rt_sf = (struct rt_sigframe __user *)
1018 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1019 if (!access_ok(rt_sf, sizeof(*rt_sf)))
1020 goto bad;
1021
1022#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1023 /*
1024 * If there is a transactional state then throw it away.
1025 * The purpose of a sigreturn is to destroy all traces of the
1026 * signal frame, this includes any transactional state created
1027 * within in. We only check for suspended as we can never be
1028 * active in the kernel, we are active, there is nothing better to
1029 * do than go ahead and Bad Thing later.
1030 * The cause is not important as there will never be a
1031 * recheckpoint so it's not user visible.
1032 */
1033 if (MSR_TM_SUSPENDED(mfmsr()))
1034 tm_reclaim_current(0);
1035
1036 if (__get_user(tmp, &rt_sf->uc.uc_link))
1037 goto bad;
1038 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1039 if (uc_transact) {
1040 u32 cmcp;
1041 struct mcontext __user *mcp;
1042
1043 if (__get_user(cmcp, &uc_transact->uc_regs))
1044 return -EFAULT;
1045 mcp = (struct mcontext __user *)(u64)cmcp;
1046 /* The top 32 bits of the MSR are stashed in the transactional
1047 * ucontext. */
1048 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1049 goto bad;
1050
1051 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1052 /* Trying to start TM on non TM system */
1053 if (!cpu_has_feature(CPU_FTR_TM))
1054 goto bad;
1055 /* We only recheckpoint on return if we're
1056 * transaction.
1057 */
1058 tm_restore = 1;
1059 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1060 goto bad;
1061 }
1062 }
1063 if (!tm_restore) {
1064 /*
1065 * Unset regs->msr because ucontext MSR TS is not
1066 * set, and recheckpoint was not called. This avoid
1067 * hitting a TM Bad thing at RFID
1068 */
1069 regs->msr &= ~MSR_TS_MASK;
1070 }
1071 /* Fall through, for non-TM restore */
1072#endif
1073 if (!tm_restore)
1074 if (do_setcontext(&rt_sf->uc, regs, 1))
1075 goto bad;
1076
1077 /*
1078 * It's not clear whether or why it is desirable to save the
1079 * sigaltstack setting on signal delivery and restore it on
1080 * signal return. But other architectures do this and we have
1081 * always done it up until now so it is probably better not to
1082 * change it. -- paulus
1083 */
1084#ifdef CONFIG_PPC64
1085 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1086 goto bad;
1087#else
1088 if (restore_altstack(&rt_sf->uc.uc_stack))
1089 goto bad;
1090#endif
1091 set_thread_flag(TIF_RESTOREALL);
1092 return 0;
1093
1094 bad:
1095 if (show_unhandled_signals)
1096 printk_ratelimited(KERN_INFO
1097 "%s[%d]: bad frame in sys_rt_sigreturn: "
1098 "%p nip %08lx lr %08lx\n",
1099 current->comm, current->pid,
1100 rt_sf, regs->nip, regs->link);
1101
1102 force_sig(SIGSEGV);
1103 return 0;
1104}
1105
1106#ifdef CONFIG_PPC32
1107SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
1108 int, ndbg, struct sig_dbg_op __user *, dbg)
1109{
1110 struct pt_regs *regs = current_pt_regs();
1111 struct sig_dbg_op op;
1112 int i;
1113 unsigned long new_msr = regs->msr;
1114#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1115 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1116#endif
1117
1118 for (i=0; i<ndbg; i++) {
1119 if (copy_from_user(&op, dbg + i, sizeof(op)))
1120 return -EFAULT;
1121 switch (op.dbg_type) {
1122 case SIG_DBG_SINGLE_STEPPING:
1123#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1124 if (op.dbg_value) {
1125 new_msr |= MSR_DE;
1126 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1127 } else {
1128 new_dbcr0 &= ~DBCR0_IC;
1129 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1130 current->thread.debug.dbcr1)) {
1131 new_msr &= ~MSR_DE;
1132 new_dbcr0 &= ~DBCR0_IDM;
1133 }
1134 }
1135#else
1136 if (op.dbg_value)
1137 new_msr |= MSR_SE;
1138 else
1139 new_msr &= ~MSR_SE;
1140#endif
1141 break;
1142 case SIG_DBG_BRANCH_TRACING:
1143#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1144 return -EINVAL;
1145#else
1146 if (op.dbg_value)
1147 new_msr |= MSR_BE;
1148 else
1149 new_msr &= ~MSR_BE;
1150#endif
1151 break;
1152
1153 default:
1154 return -EINVAL;
1155 }
1156 }
1157
1158 /* We wait until here to actually install the values in the
1159 registers so if we fail in the above loop, it will not
1160 affect the contents of these registers. After this point,
1161 failure is a problem, anyway, and it's very unlikely unless
1162 the user is really doing something wrong. */
1163 regs->msr = new_msr;
1164#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1165 current->thread.debug.dbcr0 = new_dbcr0;
1166#endif
1167
1168 if (!access_ok(ctx, sizeof(*ctx)) ||
1169 fault_in_pages_readable((u8 __user *)ctx, sizeof(*ctx)))
1170 return -EFAULT;
1171
1172 /*
1173 * If we get a fault copying the context into the kernel's
1174 * image of the user's registers, we can't just return -EFAULT
1175 * because the user's registers will be corrupted. For instance
1176 * the NIP value may have been updated but not some of the
1177 * other registers. Given that we have done the access_ok
1178 * and successfully read the first and last bytes of the region
1179 * above, this should only happen in an out-of-memory situation
1180 * or if another thread unmaps the region containing the context.
1181 * We kill the task with a SIGSEGV in this situation.
1182 */
1183 if (do_setcontext(ctx, regs, 1)) {
1184 if (show_unhandled_signals)
1185 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1186 "sys_debug_setcontext: %p nip %08lx "
1187 "lr %08lx\n",
1188 current->comm, current->pid,
1189 ctx, regs->nip, regs->link);
1190
1191 force_sig(SIGSEGV);
1192 goto out;
1193 }
1194
1195 /*
1196 * It's not clear whether or why it is desirable to save the
1197 * sigaltstack setting on signal delivery and restore it on
1198 * signal return. But other architectures do this and we have
1199 * always done it up until now so it is probably better not to
1200 * change it. -- paulus
1201 */
1202 restore_altstack(&ctx->uc_stack);
1203
1204 set_thread_flag(TIF_RESTOREALL);
1205 out:
1206 return 0;
1207}
1208#endif
1209
1210/*
1211 * OK, we're invoking a handler
1212 */
1213int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
1214 struct task_struct *tsk)
1215{
1216 struct sigcontext __user *sc;
1217 struct sigframe __user *frame;
1218 struct mcontext __user *tm_mctx = NULL;
1219 unsigned long newsp = 0;
1220 int sigret;
1221 unsigned long tramp;
1222 struct pt_regs *regs = tsk->thread.regs;
1223#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1224 /* Save the thread's msr before get_tm_stackpointer() changes it */
1225 unsigned long msr = regs->msr;
1226#endif
1227
1228 BUG_ON(tsk != current);
1229
1230 /* Set up Signal Frame */
1231 frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
1232 if (unlikely(frame == NULL))
1233 goto badframe;
1234 sc = (struct sigcontext __user *) &frame->sctx;
1235
1236#if _NSIG != 64
1237#error "Please adjust handle_signal()"
1238#endif
1239 if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
1240 || __put_user(oldset->sig[0], &sc->oldmask)
1241#ifdef CONFIG_PPC64
1242 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1243#else
1244 || __put_user(oldset->sig[1], &sc->_unused[3])
1245#endif
1246 || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1247 || __put_user(ksig->sig, &sc->signal))
1248 goto badframe;
1249
1250 if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
1251 sigret = 0;
1252 tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
1253 } else {
1254 sigret = __NR_sigreturn;
1255 tramp = (unsigned long) frame->mctx.tramp;
1256 }
1257
1258#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1259 tm_mctx = &frame->mctx_transact;
1260 if (MSR_TM_ACTIVE(msr)) {
1261 if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
1262 sigret, msr))
1263 goto badframe;
1264 }
1265 else
1266#endif
1267 {
1268 if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
1269 goto badframe;
1270 }
1271
1272 regs->link = tramp;
1273
1274 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
1275
1276 /* create a stack frame for the caller of the handler */
1277 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1278 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1279 goto badframe;
1280
1281 regs->gpr[1] = newsp;
1282 regs->gpr[3] = ksig->sig;
1283 regs->gpr[4] = (unsigned long) sc;
1284 regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
1285 /* enter the signal handler in big-endian mode */
1286 regs->msr &= ~MSR_LE;
1287 return 0;
1288
1289badframe:
1290 if (show_unhandled_signals)
1291 printk_ratelimited(KERN_INFO
1292 "%s[%d]: bad frame in handle_signal32: "
1293 "%p nip %08lx lr %08lx\n",
1294 tsk->comm, tsk->pid,
1295 frame, regs->nip, regs->link);
1296
1297 return 1;
1298}
1299
1300/*
1301 * Do a signal return; undo the signal stack.
1302 */
1303#ifdef CONFIG_PPC64
1304COMPAT_SYSCALL_DEFINE0(sigreturn)
1305#else
1306SYSCALL_DEFINE0(sigreturn)
1307#endif
1308{
1309 struct pt_regs *regs = current_pt_regs();
1310 struct sigframe __user *sf;
1311 struct sigcontext __user *sc;
1312 struct sigcontext sigctx;
1313 struct mcontext __user *sr;
1314 void __user *addr;
1315 sigset_t set;
1316#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1317 struct mcontext __user *mcp, *tm_mcp;
1318 unsigned long msr_hi;
1319#endif
1320
1321 /* Always make any pending restarted system calls return -EINTR */
1322 current->restart_block.fn = do_no_restart_syscall;
1323
1324 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1325 sc = &sf->sctx;
1326 addr = sc;
1327 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1328 goto badframe;
1329
1330#ifdef CONFIG_PPC64
1331 /*
1332 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1333 * unused part of the signal stackframe
1334 */
1335 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1336#else
1337 set.sig[0] = sigctx.oldmask;
1338 set.sig[1] = sigctx._unused[3];
1339#endif
1340 set_current_blocked(&set);
1341
1342#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1343 mcp = (struct mcontext __user *)&sf->mctx;
1344 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1345 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1346 goto badframe;
1347 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1348 if (!cpu_has_feature(CPU_FTR_TM))
1349 goto badframe;
1350 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1351 goto badframe;
1352 } else
1353#endif
1354 {
1355 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1356 addr = sr;
1357 if (!access_ok(sr, sizeof(*sr))
1358 || restore_user_regs(regs, sr, 1))
1359 goto badframe;
1360 }
1361
1362 set_thread_flag(TIF_RESTOREALL);
1363 return 0;
1364
1365badframe:
1366 if (show_unhandled_signals)
1367 printk_ratelimited(KERN_INFO
1368 "%s[%d]: bad frame in sys_sigreturn: "
1369 "%p nip %08lx lr %08lx\n",
1370 current->comm, current->pid,
1371 addr, regs->nip, regs->link);
1372
1373 force_sig(SIGSEGV);
1374 return 0;
1375}
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 "ppc32.h"
47#include <asm/unistd.h>
48#else
49#include <asm/ucontext.h>
50#include <asm/pgtable.h>
51#endif
52
53#include "signal.h"
54
55
56#ifdef CONFIG_PPC64
57#define old_sigaction old_sigaction32
58#define sigcontext sigcontext32
59#define mcontext mcontext32
60#define ucontext ucontext32
61
62#define __save_altstack __compat_save_altstack
63
64/*
65 * Userspace code may pass a ucontext which doesn't include VSX added
66 * at the end. We need to check for this case.
67 */
68#define UCONTEXTSIZEWITHOUTVSX \
69 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
70
71/*
72 * Returning 0 means we return to userspace via
73 * ret_from_except and thus restore all user
74 * registers from *regs. This is what we need
75 * to do when a signal has been delivered.
76 */
77
78#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
79#undef __SIGNAL_FRAMESIZE
80#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
81#undef ELF_NVRREG
82#define ELF_NVRREG ELF_NVRREG32
83
84/*
85 * Functions for flipping sigsets (thanks to brain dead generic
86 * implementation that makes things simple for little endian only)
87 */
88static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
89{
90 return put_compat_sigset(uset, set, sizeof(*uset));
91}
92
93static inline int get_sigset_t(sigset_t *set,
94 const compat_sigset_t __user *uset)
95{
96 return get_compat_sigset(set, uset);
97}
98
99#define to_user_ptr(p) ptr_to_compat(p)
100#define from_user_ptr(p) compat_ptr(p)
101
102static inline int save_general_regs(struct pt_regs *regs,
103 struct mcontext __user *frame)
104{
105 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
106 int i;
107 /* Force usr to alway see softe as 1 (interrupts enabled) */
108 elf_greg_t64 softe = 0x1;
109
110 WARN_ON(!FULL_REGS(regs));
111
112 for (i = 0; i <= PT_RESULT; i ++) {
113 if (i == 14 && !FULL_REGS(regs))
114 i = 32;
115 if ( i == PT_SOFTE) {
116 if(__put_user((unsigned int)softe, &frame->mc_gregs[i]))
117 return -EFAULT;
118 else
119 continue;
120 }
121 if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
122 return -EFAULT;
123 }
124 return 0;
125}
126
127static inline int restore_general_regs(struct pt_regs *regs,
128 struct mcontext __user *sr)
129{
130 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
131 int i;
132
133 for (i = 0; i <= PT_RESULT; i++) {
134 if ((i == PT_MSR) || (i == PT_SOFTE))
135 continue;
136 if (__get_user(gregs[i], &sr->mc_gregs[i]))
137 return -EFAULT;
138 }
139 return 0;
140}
141
142#else /* CONFIG_PPC64 */
143
144#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
145
146static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
147{
148 return copy_to_user(uset, set, sizeof(*uset));
149}
150
151static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
152{
153 return copy_from_user(set, uset, sizeof(*uset));
154}
155
156#define to_user_ptr(p) ((unsigned long)(p))
157#define from_user_ptr(p) ((void __user *)(p))
158
159static inline int save_general_regs(struct pt_regs *regs,
160 struct mcontext __user *frame)
161{
162 WARN_ON(!FULL_REGS(regs));
163 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
164}
165
166static inline int restore_general_regs(struct pt_regs *regs,
167 struct mcontext __user *sr)
168{
169 /* copy up to but not including MSR */
170 if (__copy_from_user(regs, &sr->mc_gregs,
171 PT_MSR * sizeof(elf_greg_t)))
172 return -EFAULT;
173 /* copy from orig_r3 (the word after the MSR) up to the end */
174 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
175 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
176 return -EFAULT;
177 return 0;
178}
179#endif
180
181/*
182 * When we have signals to deliver, we set up on the
183 * user stack, going down from the original stack pointer:
184 * an ABI gap of 56 words
185 * an mcontext struct
186 * a sigcontext struct
187 * a gap of __SIGNAL_FRAMESIZE bytes
188 *
189 * Each of these things must be a multiple of 16 bytes in size. The following
190 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
191 *
192 */
193struct sigframe {
194 struct sigcontext sctx; /* the sigcontext */
195 struct mcontext mctx; /* all the register values */
196#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
197 struct sigcontext sctx_transact;
198 struct mcontext mctx_transact;
199#endif
200 /*
201 * Programs using the rs6000/xcoff abi can save up to 19 gp
202 * regs and 18 fp regs below sp before decrementing it.
203 */
204 int abigap[56];
205};
206
207/* We use the mc_pad field for the signal return trampoline. */
208#define tramp mc_pad
209
210/*
211 * When we have rt signals to deliver, we set up on the
212 * user stack, going down from the original stack pointer:
213 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
214 * a gap of __SIGNAL_FRAMESIZE+16 bytes
215 * (the +16 is to get the siginfo and ucontext in the same
216 * positions as in older kernels).
217 *
218 * Each of these things must be a multiple of 16 bytes in size.
219 *
220 */
221struct rt_sigframe {
222#ifdef CONFIG_PPC64
223 compat_siginfo_t info;
224#else
225 struct siginfo info;
226#endif
227 struct ucontext uc;
228#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
229 struct ucontext uc_transact;
230#endif
231 /*
232 * Programs using the rs6000/xcoff abi can save up to 19 gp
233 * regs and 18 fp regs below sp before decrementing it.
234 */
235 int abigap[56];
236};
237
238#ifdef CONFIG_VSX
239unsigned long copy_fpr_to_user(void __user *to,
240 struct task_struct *task)
241{
242 u64 buf[ELF_NFPREG];
243 int i;
244
245 /* save FPR copy to local buffer then write to the thread_struct */
246 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
247 buf[i] = task->thread.TS_FPR(i);
248 buf[i] = task->thread.fp_state.fpscr;
249 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
250}
251
252unsigned long copy_fpr_from_user(struct task_struct *task,
253 void __user *from)
254{
255 u64 buf[ELF_NFPREG];
256 int i;
257
258 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
259 return 1;
260 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
261 task->thread.TS_FPR(i) = buf[i];
262 task->thread.fp_state.fpscr = buf[i];
263
264 return 0;
265}
266
267unsigned long copy_vsx_to_user(void __user *to,
268 struct task_struct *task)
269{
270 u64 buf[ELF_NVSRHALFREG];
271 int i;
272
273 /* save FPR copy to local buffer then write to the thread_struct */
274 for (i = 0; i < ELF_NVSRHALFREG; i++)
275 buf[i] = task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET];
276 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
277}
278
279unsigned long copy_vsx_from_user(struct task_struct *task,
280 void __user *from)
281{
282 u64 buf[ELF_NVSRHALFREG];
283 int i;
284
285 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
286 return 1;
287 for (i = 0; i < ELF_NVSRHALFREG ; i++)
288 task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
289 return 0;
290}
291
292#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
293unsigned long copy_ckfpr_to_user(void __user *to,
294 struct task_struct *task)
295{
296 u64 buf[ELF_NFPREG];
297 int i;
298
299 /* save FPR copy to local buffer then write to the thread_struct */
300 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
301 buf[i] = task->thread.TS_CKFPR(i);
302 buf[i] = task->thread.ckfp_state.fpscr;
303 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
304}
305
306unsigned long copy_ckfpr_from_user(struct task_struct *task,
307 void __user *from)
308{
309 u64 buf[ELF_NFPREG];
310 int i;
311
312 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
313 return 1;
314 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
315 task->thread.TS_CKFPR(i) = buf[i];
316 task->thread.ckfp_state.fpscr = buf[i];
317
318 return 0;
319}
320
321unsigned long copy_ckvsx_to_user(void __user *to,
322 struct task_struct *task)
323{
324 u64 buf[ELF_NVSRHALFREG];
325 int i;
326
327 /* save FPR copy to local buffer then write to the thread_struct */
328 for (i = 0; i < ELF_NVSRHALFREG; i++)
329 buf[i] = task->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET];
330 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
331}
332
333unsigned long copy_ckvsx_from_user(struct task_struct *task,
334 void __user *from)
335{
336 u64 buf[ELF_NVSRHALFREG];
337 int i;
338
339 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
340 return 1;
341 for (i = 0; i < ELF_NVSRHALFREG ; i++)
342 task->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
343 return 0;
344}
345#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
346#else
347inline unsigned long copy_fpr_to_user(void __user *to,
348 struct task_struct *task)
349{
350 return __copy_to_user(to, task->thread.fp_state.fpr,
351 ELF_NFPREG * sizeof(double));
352}
353
354inline unsigned long copy_fpr_from_user(struct task_struct *task,
355 void __user *from)
356{
357 return __copy_from_user(task->thread.fp_state.fpr, from,
358 ELF_NFPREG * sizeof(double));
359}
360
361#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
362inline unsigned long copy_ckfpr_to_user(void __user *to,
363 struct task_struct *task)
364{
365 return __copy_to_user(to, task->thread.ckfp_state.fpr,
366 ELF_NFPREG * sizeof(double));
367}
368
369inline unsigned long copy_ckfpr_from_user(struct task_struct *task,
370 void __user *from)
371{
372 return __copy_from_user(task->thread.ckfp_state.fpr, from,
373 ELF_NFPREG * sizeof(double));
374}
375#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
376#endif
377
378/*
379 * Save the current user registers on the user stack.
380 * We only save the altivec/spe registers if the process has used
381 * altivec/spe instructions at some point.
382 */
383static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
384 struct mcontext __user *tm_frame, int sigret,
385 int ctx_has_vsx_region)
386{
387 unsigned long msr = regs->msr;
388
389 /* Make sure floating point registers are stored in regs */
390 flush_fp_to_thread(current);
391
392 /* save general registers */
393 if (save_general_regs(regs, frame))
394 return 1;
395
396#ifdef CONFIG_ALTIVEC
397 /* save altivec registers */
398 if (current->thread.used_vr) {
399 flush_altivec_to_thread(current);
400 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
401 ELF_NVRREG * sizeof(vector128)))
402 return 1;
403 /* set MSR_VEC in the saved MSR value to indicate that
404 frame->mc_vregs contains valid data */
405 msr |= MSR_VEC;
406 }
407 /* else assert((regs->msr & MSR_VEC) == 0) */
408
409 /* We always copy to/from vrsave, it's 0 if we don't have or don't
410 * use altivec. Since VSCR only contains 32 bits saved in the least
411 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
412 * most significant bits of that same vector. --BenH
413 * Note that the current VRSAVE value is in the SPR at this point.
414 */
415 if (cpu_has_feature(CPU_FTR_ALTIVEC))
416 current->thread.vrsave = mfspr(SPRN_VRSAVE);
417 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
418 return 1;
419#endif /* CONFIG_ALTIVEC */
420 if (copy_fpr_to_user(&frame->mc_fregs, current))
421 return 1;
422
423 /*
424 * Clear the MSR VSX bit to indicate there is no valid state attached
425 * to this context, except in the specific case below where we set it.
426 */
427 msr &= ~MSR_VSX;
428#ifdef CONFIG_VSX
429 /*
430 * Copy VSR 0-31 upper half from thread_struct to local
431 * buffer, then write that to userspace. Also set MSR_VSX in
432 * the saved MSR value to indicate that frame->mc_vregs
433 * contains valid data
434 */
435 if (current->thread.used_vsr && ctx_has_vsx_region) {
436 flush_vsx_to_thread(current);
437 if (copy_vsx_to_user(&frame->mc_vsregs, current))
438 return 1;
439 msr |= MSR_VSX;
440 }
441#endif /* CONFIG_VSX */
442#ifdef CONFIG_SPE
443 /* save spe registers */
444 if (current->thread.used_spe) {
445 flush_spe_to_thread(current);
446 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
447 ELF_NEVRREG * sizeof(u32)))
448 return 1;
449 /* set MSR_SPE in the saved MSR value to indicate that
450 frame->mc_vregs contains valid data */
451 msr |= MSR_SPE;
452 }
453 /* else assert((regs->msr & MSR_SPE) == 0) */
454
455 /* We always copy to/from spefscr */
456 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
457 return 1;
458#endif /* CONFIG_SPE */
459
460 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
461 return 1;
462 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
463 * can check it on the restore to see if TM is active
464 */
465 if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
466 return 1;
467
468 if (sigret) {
469 /* Set up the sigreturn trampoline: li 0,sigret; sc */
470 if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
471 || __put_user(PPC_INST_SC, &frame->tramp[1]))
472 return 1;
473 flush_icache_range((unsigned long) &frame->tramp[0],
474 (unsigned long) &frame->tramp[2]);
475 }
476
477 return 0;
478}
479
480#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
481/*
482 * Save the current user registers on the user stack.
483 * We only save the altivec/spe registers if the process has used
484 * altivec/spe instructions at some point.
485 * We also save the transactional registers to a second ucontext in the
486 * frame.
487 *
488 * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
489 */
490static int save_tm_user_regs(struct pt_regs *regs,
491 struct mcontext __user *frame,
492 struct mcontext __user *tm_frame, int sigret)
493{
494 unsigned long msr = regs->msr;
495
496 WARN_ON(tm_suspend_disabled);
497
498 /* Remove TM bits from thread's MSR. The MSR in the sigcontext
499 * just indicates to userland that we were doing a transaction, but we
500 * don't want to return in transactional state. This also ensures
501 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
502 */
503 regs->msr &= ~MSR_TS_MASK;
504
505 /* Save both sets of general registers */
506 if (save_general_regs(¤t->thread.ckpt_regs, frame)
507 || save_general_regs(regs, tm_frame))
508 return 1;
509
510 /* Stash the top half of the 64bit MSR into the 32bit MSR word
511 * of the transactional mcontext. This way we have a backward-compatible
512 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
513 * also look at what type of transaction (T or S) was active at the
514 * time of the signal.
515 */
516 if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
517 return 1;
518
519#ifdef CONFIG_ALTIVEC
520 /* save altivec registers */
521 if (current->thread.used_vr) {
522 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
523 ELF_NVRREG * sizeof(vector128)))
524 return 1;
525 if (msr & MSR_VEC) {
526 if (__copy_to_user(&tm_frame->mc_vregs,
527 ¤t->thread.vr_state,
528 ELF_NVRREG * sizeof(vector128)))
529 return 1;
530 } else {
531 if (__copy_to_user(&tm_frame->mc_vregs,
532 ¤t->thread.ckvr_state,
533 ELF_NVRREG * sizeof(vector128)))
534 return 1;
535 }
536
537 /* set MSR_VEC in the saved MSR value to indicate that
538 * frame->mc_vregs contains valid data
539 */
540 msr |= MSR_VEC;
541 }
542
543 /* We always copy to/from vrsave, it's 0 if we don't have or don't
544 * use altivec. Since VSCR only contains 32 bits saved in the least
545 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
546 * most significant bits of that same vector. --BenH
547 */
548 if (cpu_has_feature(CPU_FTR_ALTIVEC))
549 current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
550 if (__put_user(current->thread.ckvrsave,
551 (u32 __user *)&frame->mc_vregs[32]))
552 return 1;
553 if (msr & MSR_VEC) {
554 if (__put_user(current->thread.vrsave,
555 (u32 __user *)&tm_frame->mc_vregs[32]))
556 return 1;
557 } else {
558 if (__put_user(current->thread.ckvrsave,
559 (u32 __user *)&tm_frame->mc_vregs[32]))
560 return 1;
561 }
562#endif /* CONFIG_ALTIVEC */
563
564 if (copy_ckfpr_to_user(&frame->mc_fregs, current))
565 return 1;
566 if (msr & MSR_FP) {
567 if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
568 return 1;
569 } else {
570 if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
571 return 1;
572 }
573
574#ifdef CONFIG_VSX
575 /*
576 * Copy VSR 0-31 upper half from thread_struct to local
577 * buffer, then write that to userspace. Also set MSR_VSX in
578 * the saved MSR value to indicate that frame->mc_vregs
579 * contains valid data
580 */
581 if (current->thread.used_vsr) {
582 if (copy_ckvsx_to_user(&frame->mc_vsregs, current))
583 return 1;
584 if (msr & MSR_VSX) {
585 if (copy_vsx_to_user(&tm_frame->mc_vsregs,
586 current))
587 return 1;
588 } else {
589 if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
590 return 1;
591 }
592
593 msr |= MSR_VSX;
594 }
595#endif /* CONFIG_VSX */
596#ifdef CONFIG_SPE
597 /* SPE regs are not checkpointed with TM, so this section is
598 * simply the same as in save_user_regs().
599 */
600 if (current->thread.used_spe) {
601 flush_spe_to_thread(current);
602 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
603 ELF_NEVRREG * sizeof(u32)))
604 return 1;
605 /* set MSR_SPE in the saved MSR value to indicate that
606 * frame->mc_vregs contains valid data */
607 msr |= MSR_SPE;
608 }
609
610 /* We always copy to/from spefscr */
611 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
612 return 1;
613#endif /* CONFIG_SPE */
614
615 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
616 return 1;
617 if (sigret) {
618 /* Set up the sigreturn trampoline: li 0,sigret; sc */
619 if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
620 || __put_user(PPC_INST_SC, &frame->tramp[1]))
621 return 1;
622 flush_icache_range((unsigned long) &frame->tramp[0],
623 (unsigned long) &frame->tramp[2]);
624 }
625
626 return 0;
627}
628#endif
629
630/*
631 * Restore the current user register values from the user stack,
632 * (except for MSR).
633 */
634static long restore_user_regs(struct pt_regs *regs,
635 struct mcontext __user *sr, int sig)
636{
637 long err;
638 unsigned int save_r2 = 0;
639 unsigned long msr;
640#ifdef CONFIG_VSX
641 int i;
642#endif
643
644 /*
645 * restore general registers but not including MSR or SOFTE. Also
646 * take care of keeping r2 (TLS) intact if not a signal
647 */
648 if (!sig)
649 save_r2 = (unsigned int)regs->gpr[2];
650 err = restore_general_regs(regs, sr);
651 regs->trap = 0;
652 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
653 if (!sig)
654 regs->gpr[2] = (unsigned long) save_r2;
655 if (err)
656 return 1;
657
658 /* if doing signal return, restore the previous little-endian mode */
659 if (sig)
660 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
661
662#ifdef CONFIG_ALTIVEC
663 /*
664 * Force the process to reload the altivec registers from
665 * current->thread when it next does altivec instructions
666 */
667 regs->msr &= ~MSR_VEC;
668 if (msr & MSR_VEC) {
669 /* restore altivec registers from the stack */
670 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
671 sizeof(sr->mc_vregs)))
672 return 1;
673 current->thread.used_vr = true;
674 } else if (current->thread.used_vr)
675 memset(¤t->thread.vr_state, 0,
676 ELF_NVRREG * sizeof(vector128));
677
678 /* Always get VRSAVE back */
679 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
680 return 1;
681 if (cpu_has_feature(CPU_FTR_ALTIVEC))
682 mtspr(SPRN_VRSAVE, current->thread.vrsave);
683#endif /* CONFIG_ALTIVEC */
684 if (copy_fpr_from_user(current, &sr->mc_fregs))
685 return 1;
686
687#ifdef CONFIG_VSX
688 /*
689 * Force the process to reload the VSX registers from
690 * current->thread when it next does VSX instruction.
691 */
692 regs->msr &= ~MSR_VSX;
693 if (msr & MSR_VSX) {
694 /*
695 * Restore altivec registers from the stack to a local
696 * buffer, then write this out to the thread_struct
697 */
698 if (copy_vsx_from_user(current, &sr->mc_vsregs))
699 return 1;
700 current->thread.used_vsr = true;
701 } else if (current->thread.used_vsr)
702 for (i = 0; i < 32 ; i++)
703 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
704#endif /* CONFIG_VSX */
705 /*
706 * force the process to reload the FP registers from
707 * current->thread when it next does FP instructions
708 */
709 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
710
711#ifdef CONFIG_SPE
712 /* force the process to reload the spe registers from
713 current->thread when it next does spe instructions */
714 regs->msr &= ~MSR_SPE;
715 if (msr & MSR_SPE) {
716 /* restore spe registers from the stack */
717 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
718 ELF_NEVRREG * sizeof(u32)))
719 return 1;
720 current->thread.used_spe = true;
721 } else if (current->thread.used_spe)
722 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
723
724 /* Always get SPEFSCR back */
725 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
726 return 1;
727#endif /* CONFIG_SPE */
728
729 return 0;
730}
731
732#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
733/*
734 * Restore the current user register values from the user stack, except for
735 * MSR, and recheckpoint the original checkpointed register state for processes
736 * in transactions.
737 */
738static long restore_tm_user_regs(struct pt_regs *regs,
739 struct mcontext __user *sr,
740 struct mcontext __user *tm_sr)
741{
742 long err;
743 unsigned long msr, msr_hi;
744#ifdef CONFIG_VSX
745 int i;
746#endif
747
748 if (tm_suspend_disabled)
749 return 1;
750 /*
751 * restore general registers but not including MSR or SOFTE. Also
752 * take care of keeping r2 (TLS) intact if not a signal.
753 * See comment in signal_64.c:restore_tm_sigcontexts();
754 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
755 * were set by the signal delivery.
756 */
757 err = restore_general_regs(regs, tm_sr);
758 err |= restore_general_regs(¤t->thread.ckpt_regs, sr);
759
760 err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
761
762 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
763 if (err)
764 return 1;
765
766 /* Restore the previous little-endian mode */
767 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
768
769#ifdef CONFIG_ALTIVEC
770 regs->msr &= ~MSR_VEC;
771 if (msr & MSR_VEC) {
772 /* restore altivec registers from the stack */
773 if (__copy_from_user(¤t->thread.ckvr_state, &sr->mc_vregs,
774 sizeof(sr->mc_vregs)) ||
775 __copy_from_user(¤t->thread.vr_state,
776 &tm_sr->mc_vregs,
777 sizeof(sr->mc_vregs)))
778 return 1;
779 current->thread.used_vr = true;
780 } else if (current->thread.used_vr) {
781 memset(¤t->thread.vr_state, 0,
782 ELF_NVRREG * sizeof(vector128));
783 memset(¤t->thread.ckvr_state, 0,
784 ELF_NVRREG * sizeof(vector128));
785 }
786
787 /* Always get VRSAVE back */
788 if (__get_user(current->thread.ckvrsave,
789 (u32 __user *)&sr->mc_vregs[32]) ||
790 __get_user(current->thread.vrsave,
791 (u32 __user *)&tm_sr->mc_vregs[32]))
792 return 1;
793 if (cpu_has_feature(CPU_FTR_ALTIVEC))
794 mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
795#endif /* CONFIG_ALTIVEC */
796
797 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
798
799 if (copy_fpr_from_user(current, &sr->mc_fregs) ||
800 copy_ckfpr_from_user(current, &tm_sr->mc_fregs))
801 return 1;
802
803#ifdef CONFIG_VSX
804 regs->msr &= ~MSR_VSX;
805 if (msr & MSR_VSX) {
806 /*
807 * Restore altivec registers from the stack to a local
808 * buffer, then write this out to the thread_struct
809 */
810 if (copy_vsx_from_user(current, &tm_sr->mc_vsregs) ||
811 copy_ckvsx_from_user(current, &sr->mc_vsregs))
812 return 1;
813 current->thread.used_vsr = true;
814 } else if (current->thread.used_vsr)
815 for (i = 0; i < 32 ; i++) {
816 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
817 current->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
818 }
819#endif /* CONFIG_VSX */
820
821#ifdef CONFIG_SPE
822 /* SPE regs are not checkpointed with TM, so this section is
823 * simply the same as in restore_user_regs().
824 */
825 regs->msr &= ~MSR_SPE;
826 if (msr & MSR_SPE) {
827 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
828 ELF_NEVRREG * sizeof(u32)))
829 return 1;
830 current->thread.used_spe = true;
831 } else if (current->thread.used_spe)
832 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
833
834 /* Always get SPEFSCR back */
835 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
836 + ELF_NEVRREG))
837 return 1;
838#endif /* CONFIG_SPE */
839
840 /* Get the top half of the MSR from the user context */
841 if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
842 return 1;
843 msr_hi <<= 32;
844 /* If TM bits are set to the reserved value, it's an invalid context */
845 if (MSR_TM_RESV(msr_hi))
846 return 1;
847
848 /*
849 * Disabling preemption, since it is unsafe to be preempted
850 * with MSR[TS] set without recheckpointing.
851 */
852 preempt_disable();
853
854 /*
855 * CAUTION:
856 * After regs->MSR[TS] being updated, make sure that get_user(),
857 * put_user() or similar functions are *not* called. These
858 * functions can generate page faults which will cause the process
859 * to be de-scheduled with MSR[TS] set but without calling
860 * tm_recheckpoint(). This can cause a bug.
861 *
862 * Pull in the MSR TM bits from the user context
863 */
864 regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK);
865 /* Now, recheckpoint. This loads up all of the checkpointed (older)
866 * registers, including FP and V[S]Rs. After recheckpointing, the
867 * transactional versions should be loaded.
868 */
869 tm_enable();
870 /* Make sure the transaction is marked as failed */
871 current->thread.tm_texasr |= TEXASR_FS;
872 /* This loads the checkpointed FP/VEC state, if used */
873 tm_recheckpoint(¤t->thread);
874
875 /* This loads the speculative FP/VEC state, if used */
876 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
877 if (msr & MSR_FP) {
878 load_fp_state(¤t->thread.fp_state);
879 regs->msr |= (MSR_FP | current->thread.fpexc_mode);
880 }
881#ifdef CONFIG_ALTIVEC
882 if (msr & MSR_VEC) {
883 load_vr_state(¤t->thread.vr_state);
884 regs->msr |= MSR_VEC;
885 }
886#endif
887
888 preempt_enable();
889
890 return 0;
891}
892#endif
893
894#ifdef CONFIG_PPC64
895
896#define copy_siginfo_to_user copy_siginfo_to_user32
897
898#endif /* CONFIG_PPC64 */
899
900/*
901 * Set up a signal frame for a "real-time" signal handler
902 * (one which gets siginfo).
903 */
904int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
905 struct task_struct *tsk)
906{
907 struct rt_sigframe __user *rt_sf;
908 struct mcontext __user *frame;
909 struct mcontext __user *tm_frame = NULL;
910 void __user *addr;
911 unsigned long newsp = 0;
912 int sigret;
913 unsigned long tramp;
914 struct pt_regs *regs = tsk->thread.regs;
915
916 BUG_ON(tsk != current);
917
918 /* Set up Signal Frame */
919 /* Put a Real Time Context onto stack */
920 rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
921 addr = rt_sf;
922 if (unlikely(rt_sf == NULL))
923 goto badframe;
924
925 /* Put the siginfo & fill in most of the ucontext */
926 if (copy_siginfo_to_user(&rt_sf->info, &ksig->info)
927 || __put_user(0, &rt_sf->uc.uc_flags)
928 || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
929 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
930 &rt_sf->uc.uc_regs)
931 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
932 goto badframe;
933
934 /* Save user registers on the stack */
935 frame = &rt_sf->uc.uc_mcontext;
936 addr = frame;
937 if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
938 sigret = 0;
939 tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
940 } else {
941 sigret = __NR_rt_sigreturn;
942 tramp = (unsigned long) frame->tramp;
943 }
944
945#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
946 tm_frame = &rt_sf->uc_transact.uc_mcontext;
947 if (MSR_TM_ACTIVE(regs->msr)) {
948 if (__put_user((unsigned long)&rt_sf->uc_transact,
949 &rt_sf->uc.uc_link) ||
950 __put_user((unsigned long)tm_frame,
951 &rt_sf->uc_transact.uc_regs))
952 goto badframe;
953 if (save_tm_user_regs(regs, frame, tm_frame, sigret))
954 goto badframe;
955 }
956 else
957#endif
958 {
959 if (__put_user(0, &rt_sf->uc.uc_link))
960 goto badframe;
961 if (save_user_regs(regs, frame, tm_frame, sigret, 1))
962 goto badframe;
963 }
964 regs->link = tramp;
965
966 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
967
968 /* create a stack frame for the caller of the handler */
969 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
970 addr = (void __user *)regs->gpr[1];
971 if (put_user(regs->gpr[1], (u32 __user *)newsp))
972 goto badframe;
973
974 /* Fill registers for signal handler */
975 regs->gpr[1] = newsp;
976 regs->gpr[3] = ksig->sig;
977 regs->gpr[4] = (unsigned long) &rt_sf->info;
978 regs->gpr[5] = (unsigned long) &rt_sf->uc;
979 regs->gpr[6] = (unsigned long) rt_sf;
980 regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
981 /* enter the signal handler in native-endian mode */
982 regs->msr &= ~MSR_LE;
983 regs->msr |= (MSR_KERNEL & MSR_LE);
984 return 0;
985
986badframe:
987 if (show_unhandled_signals)
988 printk_ratelimited(KERN_INFO
989 "%s[%d]: bad frame in handle_rt_signal32: "
990 "%p nip %08lx lr %08lx\n",
991 tsk->comm, tsk->pid,
992 addr, regs->nip, regs->link);
993
994 return 1;
995}
996
997static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
998{
999 sigset_t set;
1000 struct mcontext __user *mcp;
1001
1002 if (get_sigset_t(&set, &ucp->uc_sigmask))
1003 return -EFAULT;
1004#ifdef CONFIG_PPC64
1005 {
1006 u32 cmcp;
1007
1008 if (__get_user(cmcp, &ucp->uc_regs))
1009 return -EFAULT;
1010 mcp = (struct mcontext __user *)(u64)cmcp;
1011 /* no need to check access_ok(mcp), since mcp < 4GB */
1012 }
1013#else
1014 if (__get_user(mcp, &ucp->uc_regs))
1015 return -EFAULT;
1016 if (!access_ok(mcp, sizeof(*mcp)))
1017 return -EFAULT;
1018#endif
1019 set_current_blocked(&set);
1020 if (restore_user_regs(regs, mcp, sig))
1021 return -EFAULT;
1022
1023 return 0;
1024}
1025
1026#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1027static int do_setcontext_tm(struct ucontext __user *ucp,
1028 struct ucontext __user *tm_ucp,
1029 struct pt_regs *regs)
1030{
1031 sigset_t set;
1032 struct mcontext __user *mcp;
1033 struct mcontext __user *tm_mcp;
1034 u32 cmcp;
1035 u32 tm_cmcp;
1036
1037 if (get_sigset_t(&set, &ucp->uc_sigmask))
1038 return -EFAULT;
1039
1040 if (__get_user(cmcp, &ucp->uc_regs) ||
1041 __get_user(tm_cmcp, &tm_ucp->uc_regs))
1042 return -EFAULT;
1043 mcp = (struct mcontext __user *)(u64)cmcp;
1044 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
1045 /* no need to check access_ok(mcp), since mcp < 4GB */
1046
1047 set_current_blocked(&set);
1048 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1049 return -EFAULT;
1050
1051 return 0;
1052}
1053#endif
1054
1055#ifdef CONFIG_PPC64
1056COMPAT_SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
1057 struct ucontext __user *, new_ctx, int, ctx_size)
1058#else
1059SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
1060 struct ucontext __user *, new_ctx, long, ctx_size)
1061#endif
1062{
1063 struct pt_regs *regs = current_pt_regs();
1064 int ctx_has_vsx_region = 0;
1065
1066#ifdef CONFIG_PPC64
1067 unsigned long new_msr = 0;
1068
1069 if (new_ctx) {
1070 struct mcontext __user *mcp;
1071 u32 cmcp;
1072
1073 /*
1074 * Get pointer to the real mcontext. No need for
1075 * access_ok since we are dealing with compat
1076 * pointers.
1077 */
1078 if (__get_user(cmcp, &new_ctx->uc_regs))
1079 return -EFAULT;
1080 mcp = (struct mcontext __user *)(u64)cmcp;
1081 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
1082 return -EFAULT;
1083 }
1084 /*
1085 * Check that the context is not smaller than the original
1086 * size (with VMX but without VSX)
1087 */
1088 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
1089 return -EINVAL;
1090 /*
1091 * If the new context state sets the MSR VSX bits but
1092 * it doesn't provide VSX state.
1093 */
1094 if ((ctx_size < sizeof(struct ucontext)) &&
1095 (new_msr & MSR_VSX))
1096 return -EINVAL;
1097 /* Does the context have enough room to store VSX data? */
1098 if (ctx_size >= sizeof(struct ucontext))
1099 ctx_has_vsx_region = 1;
1100#else
1101 /* Context size is for future use. Right now, we only make sure
1102 * we are passed something we understand
1103 */
1104 if (ctx_size < sizeof(struct ucontext))
1105 return -EINVAL;
1106#endif
1107 if (old_ctx != NULL) {
1108 struct mcontext __user *mctx;
1109
1110 /*
1111 * old_ctx might not be 16-byte aligned, in which
1112 * case old_ctx->uc_mcontext won't be either.
1113 * Because we have the old_ctx->uc_pad2 field
1114 * before old_ctx->uc_mcontext, we need to round down
1115 * from &old_ctx->uc_mcontext to a 16-byte boundary.
1116 */
1117 mctx = (struct mcontext __user *)
1118 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
1119 if (!access_ok(old_ctx, ctx_size)
1120 || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
1121 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
1122 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
1123 return -EFAULT;
1124 }
1125 if (new_ctx == NULL)
1126 return 0;
1127 if (!access_ok(new_ctx, ctx_size) ||
1128 fault_in_pages_readable((u8 __user *)new_ctx, ctx_size))
1129 return -EFAULT;
1130
1131 /*
1132 * If we get a fault copying the context into the kernel's
1133 * image of the user's registers, we can't just return -EFAULT
1134 * because the user's registers will be corrupted. For instance
1135 * the NIP value may have been updated but not some of the
1136 * other registers. Given that we have done the access_ok
1137 * and successfully read the first and last bytes of the region
1138 * above, this should only happen in an out-of-memory situation
1139 * or if another thread unmaps the region containing the context.
1140 * We kill the task with a SIGSEGV in this situation.
1141 */
1142 if (do_setcontext(new_ctx, regs, 0))
1143 do_exit(SIGSEGV);
1144
1145 set_thread_flag(TIF_RESTOREALL);
1146 return 0;
1147}
1148
1149#ifdef CONFIG_PPC64
1150COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
1151#else
1152SYSCALL_DEFINE0(rt_sigreturn)
1153#endif
1154{
1155 struct rt_sigframe __user *rt_sf;
1156 struct pt_regs *regs = current_pt_regs();
1157 int tm_restore = 0;
1158#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1159 struct ucontext __user *uc_transact;
1160 unsigned long msr_hi;
1161 unsigned long tmp;
1162#endif
1163 /* Always make any pending restarted system calls return -EINTR */
1164 current->restart_block.fn = do_no_restart_syscall;
1165
1166 rt_sf = (struct rt_sigframe __user *)
1167 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1168 if (!access_ok(rt_sf, sizeof(*rt_sf)))
1169 goto bad;
1170
1171#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1172 /*
1173 * If there is a transactional state then throw it away.
1174 * The purpose of a sigreturn is to destroy all traces of the
1175 * signal frame, this includes any transactional state created
1176 * within in. We only check for suspended as we can never be
1177 * active in the kernel, we are active, there is nothing better to
1178 * do than go ahead and Bad Thing later.
1179 * The cause is not important as there will never be a
1180 * recheckpoint so it's not user visible.
1181 */
1182 if (MSR_TM_SUSPENDED(mfmsr()))
1183 tm_reclaim_current(0);
1184
1185 if (__get_user(tmp, &rt_sf->uc.uc_link))
1186 goto bad;
1187 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1188 if (uc_transact) {
1189 u32 cmcp;
1190 struct mcontext __user *mcp;
1191
1192 if (__get_user(cmcp, &uc_transact->uc_regs))
1193 return -EFAULT;
1194 mcp = (struct mcontext __user *)(u64)cmcp;
1195 /* The top 32 bits of the MSR are stashed in the transactional
1196 * ucontext. */
1197 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1198 goto bad;
1199
1200 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1201 /* Trying to start TM on non TM system */
1202 if (!cpu_has_feature(CPU_FTR_TM))
1203 goto bad;
1204 /* We only recheckpoint on return if we're
1205 * transaction.
1206 */
1207 tm_restore = 1;
1208 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1209 goto bad;
1210 }
1211 }
1212 if (!tm_restore) {
1213 /*
1214 * Unset regs->msr because ucontext MSR TS is not
1215 * set, and recheckpoint was not called. This avoid
1216 * hitting a TM Bad thing at RFID
1217 */
1218 regs->msr &= ~MSR_TS_MASK;
1219 }
1220 /* Fall through, for non-TM restore */
1221#endif
1222 if (!tm_restore)
1223 if (do_setcontext(&rt_sf->uc, regs, 1))
1224 goto bad;
1225
1226 /*
1227 * It's not clear whether or why it is desirable to save the
1228 * sigaltstack setting on signal delivery and restore it on
1229 * signal return. But other architectures do this and we have
1230 * always done it up until now so it is probably better not to
1231 * change it. -- paulus
1232 */
1233#ifdef CONFIG_PPC64
1234 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1235 goto bad;
1236#else
1237 if (restore_altstack(&rt_sf->uc.uc_stack))
1238 goto bad;
1239#endif
1240 set_thread_flag(TIF_RESTOREALL);
1241 return 0;
1242
1243 bad:
1244 if (show_unhandled_signals)
1245 printk_ratelimited(KERN_INFO
1246 "%s[%d]: bad frame in sys_rt_sigreturn: "
1247 "%p nip %08lx lr %08lx\n",
1248 current->comm, current->pid,
1249 rt_sf, regs->nip, regs->link);
1250
1251 force_sig(SIGSEGV);
1252 return 0;
1253}
1254
1255#ifdef CONFIG_PPC32
1256SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
1257 int, ndbg, struct sig_dbg_op __user *, dbg)
1258{
1259 struct pt_regs *regs = current_pt_regs();
1260 struct sig_dbg_op op;
1261 int i;
1262 unsigned long new_msr = regs->msr;
1263#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1264 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1265#endif
1266
1267 for (i=0; i<ndbg; i++) {
1268 if (copy_from_user(&op, dbg + i, sizeof(op)))
1269 return -EFAULT;
1270 switch (op.dbg_type) {
1271 case SIG_DBG_SINGLE_STEPPING:
1272#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1273 if (op.dbg_value) {
1274 new_msr |= MSR_DE;
1275 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1276 } else {
1277 new_dbcr0 &= ~DBCR0_IC;
1278 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1279 current->thread.debug.dbcr1)) {
1280 new_msr &= ~MSR_DE;
1281 new_dbcr0 &= ~DBCR0_IDM;
1282 }
1283 }
1284#else
1285 if (op.dbg_value)
1286 new_msr |= MSR_SE;
1287 else
1288 new_msr &= ~MSR_SE;
1289#endif
1290 break;
1291 case SIG_DBG_BRANCH_TRACING:
1292#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1293 return -EINVAL;
1294#else
1295 if (op.dbg_value)
1296 new_msr |= MSR_BE;
1297 else
1298 new_msr &= ~MSR_BE;
1299#endif
1300 break;
1301
1302 default:
1303 return -EINVAL;
1304 }
1305 }
1306
1307 /* We wait until here to actually install the values in the
1308 registers so if we fail in the above loop, it will not
1309 affect the contents of these registers. After this point,
1310 failure is a problem, anyway, and it's very unlikely unless
1311 the user is really doing something wrong. */
1312 regs->msr = new_msr;
1313#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1314 current->thread.debug.dbcr0 = new_dbcr0;
1315#endif
1316
1317 if (!access_ok(ctx, sizeof(*ctx)) ||
1318 fault_in_pages_readable((u8 __user *)ctx, sizeof(*ctx)))
1319 return -EFAULT;
1320
1321 /*
1322 * If we get a fault copying the context into the kernel's
1323 * image of the user's registers, we can't just return -EFAULT
1324 * because the user's registers will be corrupted. For instance
1325 * the NIP value may have been updated but not some of the
1326 * other registers. Given that we have done the access_ok
1327 * and successfully read the first and last bytes of the region
1328 * above, this should only happen in an out-of-memory situation
1329 * or if another thread unmaps the region containing the context.
1330 * We kill the task with a SIGSEGV in this situation.
1331 */
1332 if (do_setcontext(ctx, regs, 1)) {
1333 if (show_unhandled_signals)
1334 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1335 "sys_debug_setcontext: %p nip %08lx "
1336 "lr %08lx\n",
1337 current->comm, current->pid,
1338 ctx, regs->nip, regs->link);
1339
1340 force_sig(SIGSEGV);
1341 goto out;
1342 }
1343
1344 /*
1345 * It's not clear whether or why it is desirable to save the
1346 * sigaltstack setting on signal delivery and restore it on
1347 * signal return. But other architectures do this and we have
1348 * always done it up until now so it is probably better not to
1349 * change it. -- paulus
1350 */
1351 restore_altstack(&ctx->uc_stack);
1352
1353 set_thread_flag(TIF_RESTOREALL);
1354 out:
1355 return 0;
1356}
1357#endif
1358
1359/*
1360 * OK, we're invoking a handler
1361 */
1362int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
1363 struct task_struct *tsk)
1364{
1365 struct sigcontext __user *sc;
1366 struct sigframe __user *frame;
1367 struct mcontext __user *tm_mctx = NULL;
1368 unsigned long newsp = 0;
1369 int sigret;
1370 unsigned long tramp;
1371 struct pt_regs *regs = tsk->thread.regs;
1372
1373 BUG_ON(tsk != current);
1374
1375 /* Set up Signal Frame */
1376 frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
1377 if (unlikely(frame == NULL))
1378 goto badframe;
1379 sc = (struct sigcontext __user *) &frame->sctx;
1380
1381#if _NSIG != 64
1382#error "Please adjust handle_signal()"
1383#endif
1384 if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
1385 || __put_user(oldset->sig[0], &sc->oldmask)
1386#ifdef CONFIG_PPC64
1387 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1388#else
1389 || __put_user(oldset->sig[1], &sc->_unused[3])
1390#endif
1391 || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1392 || __put_user(ksig->sig, &sc->signal))
1393 goto badframe;
1394
1395 if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
1396 sigret = 0;
1397 tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
1398 } else {
1399 sigret = __NR_sigreturn;
1400 tramp = (unsigned long) frame->mctx.tramp;
1401 }
1402
1403#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1404 tm_mctx = &frame->mctx_transact;
1405 if (MSR_TM_ACTIVE(regs->msr)) {
1406 if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
1407 sigret))
1408 goto badframe;
1409 }
1410 else
1411#endif
1412 {
1413 if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
1414 goto badframe;
1415 }
1416
1417 regs->link = tramp;
1418
1419 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
1420
1421 /* create a stack frame for the caller of the handler */
1422 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1423 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1424 goto badframe;
1425
1426 regs->gpr[1] = newsp;
1427 regs->gpr[3] = ksig->sig;
1428 regs->gpr[4] = (unsigned long) sc;
1429 regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
1430 /* enter the signal handler in big-endian mode */
1431 regs->msr &= ~MSR_LE;
1432 return 0;
1433
1434badframe:
1435 if (show_unhandled_signals)
1436 printk_ratelimited(KERN_INFO
1437 "%s[%d]: bad frame in handle_signal32: "
1438 "%p nip %08lx lr %08lx\n",
1439 tsk->comm, tsk->pid,
1440 frame, regs->nip, regs->link);
1441
1442 return 1;
1443}
1444
1445/*
1446 * Do a signal return; undo the signal stack.
1447 */
1448#ifdef CONFIG_PPC64
1449COMPAT_SYSCALL_DEFINE0(sigreturn)
1450#else
1451SYSCALL_DEFINE0(sigreturn)
1452#endif
1453{
1454 struct pt_regs *regs = current_pt_regs();
1455 struct sigframe __user *sf;
1456 struct sigcontext __user *sc;
1457 struct sigcontext sigctx;
1458 struct mcontext __user *sr;
1459 void __user *addr;
1460 sigset_t set;
1461#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1462 struct mcontext __user *mcp, *tm_mcp;
1463 unsigned long msr_hi;
1464#endif
1465
1466 /* Always make any pending restarted system calls return -EINTR */
1467 current->restart_block.fn = do_no_restart_syscall;
1468
1469 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1470 sc = &sf->sctx;
1471 addr = sc;
1472 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1473 goto badframe;
1474
1475#ifdef CONFIG_PPC64
1476 /*
1477 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1478 * unused part of the signal stackframe
1479 */
1480 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1481#else
1482 set.sig[0] = sigctx.oldmask;
1483 set.sig[1] = sigctx._unused[3];
1484#endif
1485 set_current_blocked(&set);
1486
1487#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1488 mcp = (struct mcontext __user *)&sf->mctx;
1489 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1490 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1491 goto badframe;
1492 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1493 if (!cpu_has_feature(CPU_FTR_TM))
1494 goto badframe;
1495 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1496 goto badframe;
1497 } else
1498#endif
1499 {
1500 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1501 addr = sr;
1502 if (!access_ok(sr, sizeof(*sr))
1503 || restore_user_regs(regs, sr, 1))
1504 goto badframe;
1505 }
1506
1507 set_thread_flag(TIF_RESTOREALL);
1508 return 0;
1509
1510badframe:
1511 if (show_unhandled_signals)
1512 printk_ratelimited(KERN_INFO
1513 "%s[%d]: bad frame in sys_sigreturn: "
1514 "%p nip %08lx lr %08lx\n",
1515 current->comm, current->pid,
1516 addr, regs->nip, regs->link);
1517
1518 force_sig(SIGSEGV);
1519 return 0;
1520}