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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 <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}
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 <asm/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#ifdef CONFIG_PPC64
48#include "ppc32.h"
49#include <asm/unistd.h>
50#else
51#include <asm/ucontext.h>
52#include <asm/pgtable.h>
53#endif
54
55#include "signal.h"
56
57#undef DEBUG_SIG
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 compat_sigset_t cset;
98
99 switch (_NSIG_WORDS) {
100 case 4: cset.sig[6] = set->sig[3] & 0xffffffffull;
101 cset.sig[7] = set->sig[3] >> 32;
102 case 3: cset.sig[4] = set->sig[2] & 0xffffffffull;
103 cset.sig[5] = set->sig[2] >> 32;
104 case 2: cset.sig[2] = set->sig[1] & 0xffffffffull;
105 cset.sig[3] = set->sig[1] >> 32;
106 case 1: cset.sig[0] = set->sig[0] & 0xffffffffull;
107 cset.sig[1] = set->sig[0] >> 32;
108 }
109 return copy_to_user(uset, &cset, sizeof(*uset));
110}
111
112static inline int get_sigset_t(sigset_t *set,
113 const compat_sigset_t __user *uset)
114{
115 compat_sigset_t s32;
116
117 if (copy_from_user(&s32, uset, sizeof(*uset)))
118 return -EFAULT;
119
120 /*
121 * Swap the 2 words of the 64-bit sigset_t (they are stored
122 * in the "wrong" endian in 32-bit user storage).
123 */
124 switch (_NSIG_WORDS) {
125 case 4: set->sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
126 case 3: set->sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
127 case 2: set->sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
128 case 1: set->sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
129 }
130 return 0;
131}
132
133#define to_user_ptr(p) ptr_to_compat(p)
134#define from_user_ptr(p) compat_ptr(p)
135
136static inline int save_general_regs(struct pt_regs *regs,
137 struct mcontext __user *frame)
138{
139 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
140 int i;
141
142 WARN_ON(!FULL_REGS(regs));
143
144 for (i = 0; i <= PT_RESULT; i ++) {
145 if (i == 14 && !FULL_REGS(regs))
146 i = 32;
147 if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
148 return -EFAULT;
149 }
150 return 0;
151}
152
153static inline int restore_general_regs(struct pt_regs *regs,
154 struct mcontext __user *sr)
155{
156 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
157 int i;
158
159 for (i = 0; i <= PT_RESULT; i++) {
160 if ((i == PT_MSR) || (i == PT_SOFTE))
161 continue;
162 if (__get_user(gregs[i], &sr->mc_gregs[i]))
163 return -EFAULT;
164 }
165 return 0;
166}
167
168#else /* CONFIG_PPC64 */
169
170#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
171
172static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
173{
174 return copy_to_user(uset, set, sizeof(*uset));
175}
176
177static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
178{
179 return copy_from_user(set, uset, sizeof(*uset));
180}
181
182#define to_user_ptr(p) ((unsigned long)(p))
183#define from_user_ptr(p) ((void __user *)(p))
184
185static inline int save_general_regs(struct pt_regs *regs,
186 struct mcontext __user *frame)
187{
188 WARN_ON(!FULL_REGS(regs));
189 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
190}
191
192static inline int restore_general_regs(struct pt_regs *regs,
193 struct mcontext __user *sr)
194{
195 /* copy up to but not including MSR */
196 if (__copy_from_user(regs, &sr->mc_gregs,
197 PT_MSR * sizeof(elf_greg_t)))
198 return -EFAULT;
199 /* copy from orig_r3 (the word after the MSR) up to the end */
200 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
201 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
202 return -EFAULT;
203 return 0;
204}
205#endif
206
207/*
208 * When we have signals to deliver, we set up on the
209 * user stack, going down from the original stack pointer:
210 * an ABI gap of 56 words
211 * an mcontext struct
212 * a sigcontext struct
213 * a gap of __SIGNAL_FRAMESIZE bytes
214 *
215 * Each of these things must be a multiple of 16 bytes in size. The following
216 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
217 *
218 */
219struct sigframe {
220 struct sigcontext sctx; /* the sigcontext */
221 struct mcontext mctx; /* all the register values */
222#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
223 struct sigcontext sctx_transact;
224 struct mcontext mctx_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/* We use the mc_pad field for the signal return trampoline. */
234#define tramp mc_pad
235
236/*
237 * When we have rt signals to deliver, we set up on the
238 * user stack, going down from the original stack pointer:
239 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
240 * a gap of __SIGNAL_FRAMESIZE+16 bytes
241 * (the +16 is to get the siginfo and ucontext in the same
242 * positions as in older kernels).
243 *
244 * Each of these things must be a multiple of 16 bytes in size.
245 *
246 */
247struct rt_sigframe {
248#ifdef CONFIG_PPC64
249 compat_siginfo_t info;
250#else
251 struct siginfo info;
252#endif
253 struct ucontext uc;
254#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
255 struct ucontext uc_transact;
256#endif
257 /*
258 * Programs using the rs6000/xcoff abi can save up to 19 gp
259 * regs and 18 fp regs below sp before decrementing it.
260 */
261 int abigap[56];
262};
263
264#ifdef CONFIG_VSX
265unsigned long copy_fpr_to_user(void __user *to,
266 struct task_struct *task)
267{
268 u64 buf[ELF_NFPREG];
269 int i;
270
271 /* save FPR copy to local buffer then write to the thread_struct */
272 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
273 buf[i] = task->thread.TS_FPR(i);
274 buf[i] = task->thread.fp_state.fpscr;
275 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
276}
277
278unsigned long copy_fpr_from_user(struct task_struct *task,
279 void __user *from)
280{
281 u64 buf[ELF_NFPREG];
282 int i;
283
284 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
285 return 1;
286 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
287 task->thread.TS_FPR(i) = buf[i];
288 task->thread.fp_state.fpscr = buf[i];
289
290 return 0;
291}
292
293unsigned long copy_vsx_to_user(void __user *to,
294 struct task_struct *task)
295{
296 u64 buf[ELF_NVSRHALFREG];
297 int i;
298
299 /* save FPR copy to local buffer then write to the thread_struct */
300 for (i = 0; i < ELF_NVSRHALFREG; i++)
301 buf[i] = task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET];
302 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
303}
304
305unsigned long copy_vsx_from_user(struct task_struct *task,
306 void __user *from)
307{
308 u64 buf[ELF_NVSRHALFREG];
309 int i;
310
311 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
312 return 1;
313 for (i = 0; i < ELF_NVSRHALFREG ; i++)
314 task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
315 return 0;
316}
317
318#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
319unsigned long copy_transact_fpr_to_user(void __user *to,
320 struct task_struct *task)
321{
322 u64 buf[ELF_NFPREG];
323 int i;
324
325 /* save FPR copy to local buffer then write to the thread_struct */
326 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
327 buf[i] = task->thread.TS_TRANS_FPR(i);
328 buf[i] = task->thread.transact_fp.fpscr;
329 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
330}
331
332unsigned long copy_transact_fpr_from_user(struct task_struct *task,
333 void __user *from)
334{
335 u64 buf[ELF_NFPREG];
336 int i;
337
338 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
339 return 1;
340 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
341 task->thread.TS_TRANS_FPR(i) = buf[i];
342 task->thread.transact_fp.fpscr = buf[i];
343
344 return 0;
345}
346
347unsigned long copy_transact_vsx_to_user(void __user *to,
348 struct task_struct *task)
349{
350 u64 buf[ELF_NVSRHALFREG];
351 int i;
352
353 /* save FPR copy to local buffer then write to the thread_struct */
354 for (i = 0; i < ELF_NVSRHALFREG; i++)
355 buf[i] = task->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET];
356 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
357}
358
359unsigned long copy_transact_vsx_from_user(struct task_struct *task,
360 void __user *from)
361{
362 u64 buf[ELF_NVSRHALFREG];
363 int i;
364
365 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
366 return 1;
367 for (i = 0; i < ELF_NVSRHALFREG ; i++)
368 task->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET] = buf[i];
369 return 0;
370}
371#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
372#else
373inline unsigned long copy_fpr_to_user(void __user *to,
374 struct task_struct *task)
375{
376 return __copy_to_user(to, task->thread.fp_state.fpr,
377 ELF_NFPREG * sizeof(double));
378}
379
380inline unsigned long copy_fpr_from_user(struct task_struct *task,
381 void __user *from)
382{
383 return __copy_from_user(task->thread.fp_state.fpr, from,
384 ELF_NFPREG * sizeof(double));
385}
386
387#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
388inline unsigned long copy_transact_fpr_to_user(void __user *to,
389 struct task_struct *task)
390{
391 return __copy_to_user(to, task->thread.transact_fp.fpr,
392 ELF_NFPREG * sizeof(double));
393}
394
395inline unsigned long copy_transact_fpr_from_user(struct task_struct *task,
396 void __user *from)
397{
398 return __copy_from_user(task->thread.transact_fp.fpr, from,
399 ELF_NFPREG * sizeof(double));
400}
401#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
402#endif
403
404/*
405 * Save the current user registers on the user stack.
406 * We only save the altivec/spe registers if the process has used
407 * altivec/spe instructions at some point.
408 */
409static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
410 struct mcontext __user *tm_frame, int sigret,
411 int ctx_has_vsx_region)
412{
413 unsigned long msr = regs->msr;
414
415 /* Make sure floating point registers are stored in regs */
416 flush_fp_to_thread(current);
417
418 /* save general registers */
419 if (save_general_regs(regs, frame))
420 return 1;
421
422#ifdef CONFIG_ALTIVEC
423 /* save altivec registers */
424 if (current->thread.used_vr) {
425 flush_altivec_to_thread(current);
426 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
427 ELF_NVRREG * sizeof(vector128)))
428 return 1;
429 /* set MSR_VEC in the saved MSR value to indicate that
430 frame->mc_vregs contains valid data */
431 msr |= MSR_VEC;
432 }
433 /* else assert((regs->msr & MSR_VEC) == 0) */
434
435 /* We always copy to/from vrsave, it's 0 if we don't have or don't
436 * use altivec. Since VSCR only contains 32 bits saved in the least
437 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
438 * most significant bits of that same vector. --BenH
439 * Note that the current VRSAVE value is in the SPR at this point.
440 */
441 if (cpu_has_feature(CPU_FTR_ALTIVEC))
442 current->thread.vrsave = mfspr(SPRN_VRSAVE);
443 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
444 return 1;
445#endif /* CONFIG_ALTIVEC */
446 if (copy_fpr_to_user(&frame->mc_fregs, current))
447 return 1;
448
449 /*
450 * Clear the MSR VSX bit to indicate there is no valid state attached
451 * to this context, except in the specific case below where we set it.
452 */
453 msr &= ~MSR_VSX;
454#ifdef CONFIG_VSX
455 /*
456 * Copy VSR 0-31 upper half from thread_struct to local
457 * buffer, then write that to userspace. Also set MSR_VSX in
458 * the saved MSR value to indicate that frame->mc_vregs
459 * contains valid data
460 */
461 if (current->thread.used_vsr && ctx_has_vsx_region) {
462 __giveup_vsx(current);
463 if (copy_vsx_to_user(&frame->mc_vsregs, current))
464 return 1;
465 msr |= MSR_VSX;
466 }
467#endif /* CONFIG_VSX */
468#ifdef CONFIG_SPE
469 /* save spe registers */
470 if (current->thread.used_spe) {
471 flush_spe_to_thread(current);
472 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
473 ELF_NEVRREG * sizeof(u32)))
474 return 1;
475 /* set MSR_SPE in the saved MSR value to indicate that
476 frame->mc_vregs contains valid data */
477 msr |= MSR_SPE;
478 }
479 /* else assert((regs->msr & MSR_SPE) == 0) */
480
481 /* We always copy to/from spefscr */
482 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
483 return 1;
484#endif /* CONFIG_SPE */
485
486 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
487 return 1;
488 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
489 * can check it on the restore to see if TM is active
490 */
491 if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
492 return 1;
493
494 if (sigret) {
495 /* Set up the sigreturn trampoline: li r0,sigret; sc */
496 if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
497 || __put_user(0x44000002UL, &frame->tramp[1]))
498 return 1;
499 flush_icache_range((unsigned long) &frame->tramp[0],
500 (unsigned long) &frame->tramp[2]);
501 }
502
503 return 0;
504}
505
506#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
507/*
508 * Save the current user registers on the user stack.
509 * We only save the altivec/spe registers if the process has used
510 * altivec/spe instructions at some point.
511 * We also save the transactional registers to a second ucontext in the
512 * frame.
513 *
514 * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
515 */
516static int save_tm_user_regs(struct pt_regs *regs,
517 struct mcontext __user *frame,
518 struct mcontext __user *tm_frame, int sigret)
519{
520 unsigned long msr = regs->msr;
521
522 /* Remove TM bits from thread's MSR. The MSR in the sigcontext
523 * just indicates to userland that we were doing a transaction, but we
524 * don't want to return in transactional state. This also ensures
525 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
526 */
527 regs->msr &= ~MSR_TS_MASK;
528
529 /* Make sure floating point registers are stored in regs */
530 flush_fp_to_thread(current);
531
532 /* Save both sets of general registers */
533 if (save_general_regs(¤t->thread.ckpt_regs, frame)
534 || save_general_regs(regs, tm_frame))
535 return 1;
536
537 /* Stash the top half of the 64bit MSR into the 32bit MSR word
538 * of the transactional mcontext. This way we have a backward-compatible
539 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
540 * also look at what type of transaction (T or S) was active at the
541 * time of the signal.
542 */
543 if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
544 return 1;
545
546#ifdef CONFIG_ALTIVEC
547 /* save altivec registers */
548 if (current->thread.used_vr) {
549 flush_altivec_to_thread(current);
550 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
551 ELF_NVRREG * sizeof(vector128)))
552 return 1;
553 if (msr & MSR_VEC) {
554 if (__copy_to_user(&tm_frame->mc_vregs,
555 ¤t->thread.transact_vr,
556 ELF_NVRREG * sizeof(vector128)))
557 return 1;
558 } else {
559 if (__copy_to_user(&tm_frame->mc_vregs,
560 ¤t->thread.vr_state,
561 ELF_NVRREG * sizeof(vector128)))
562 return 1;
563 }
564
565 /* set MSR_VEC in the saved MSR value to indicate that
566 * frame->mc_vregs contains valid data
567 */
568 msr |= MSR_VEC;
569 }
570
571 /* We always copy to/from vrsave, it's 0 if we don't have or don't
572 * use altivec. Since VSCR only contains 32 bits saved in the least
573 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
574 * most significant bits of that same vector. --BenH
575 */
576 if (cpu_has_feature(CPU_FTR_ALTIVEC))
577 current->thread.vrsave = mfspr(SPRN_VRSAVE);
578 if (__put_user(current->thread.vrsave,
579 (u32 __user *)&frame->mc_vregs[32]))
580 return 1;
581 if (msr & MSR_VEC) {
582 if (__put_user(current->thread.transact_vrsave,
583 (u32 __user *)&tm_frame->mc_vregs[32]))
584 return 1;
585 } else {
586 if (__put_user(current->thread.vrsave,
587 (u32 __user *)&tm_frame->mc_vregs[32]))
588 return 1;
589 }
590#endif /* CONFIG_ALTIVEC */
591
592 if (copy_fpr_to_user(&frame->mc_fregs, current))
593 return 1;
594 if (msr & MSR_FP) {
595 if (copy_transact_fpr_to_user(&tm_frame->mc_fregs, current))
596 return 1;
597 } else {
598 if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
599 return 1;
600 }
601
602#ifdef CONFIG_VSX
603 /*
604 * Copy VSR 0-31 upper half from thread_struct to local
605 * buffer, then write that to userspace. Also set MSR_VSX in
606 * the saved MSR value to indicate that frame->mc_vregs
607 * contains valid data
608 */
609 if (current->thread.used_vsr) {
610 __giveup_vsx(current);
611 if (copy_vsx_to_user(&frame->mc_vsregs, current))
612 return 1;
613 if (msr & MSR_VSX) {
614 if (copy_transact_vsx_to_user(&tm_frame->mc_vsregs,
615 current))
616 return 1;
617 } else {
618 if (copy_vsx_to_user(&tm_frame->mc_vsregs, current))
619 return 1;
620 }
621
622 msr |= MSR_VSX;
623 }
624#endif /* CONFIG_VSX */
625#ifdef CONFIG_SPE
626 /* SPE regs are not checkpointed with TM, so this section is
627 * simply the same as in save_user_regs().
628 */
629 if (current->thread.used_spe) {
630 flush_spe_to_thread(current);
631 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
632 ELF_NEVRREG * sizeof(u32)))
633 return 1;
634 /* set MSR_SPE in the saved MSR value to indicate that
635 * frame->mc_vregs contains valid data */
636 msr |= MSR_SPE;
637 }
638
639 /* We always copy to/from spefscr */
640 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
641 return 1;
642#endif /* CONFIG_SPE */
643
644 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
645 return 1;
646 if (sigret) {
647 /* Set up the sigreturn trampoline: li r0,sigret; sc */
648 if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
649 || __put_user(0x44000002UL, &frame->tramp[1]))
650 return 1;
651 flush_icache_range((unsigned long) &frame->tramp[0],
652 (unsigned long) &frame->tramp[2]);
653 }
654
655 return 0;
656}
657#endif
658
659/*
660 * Restore the current user register values from the user stack,
661 * (except for MSR).
662 */
663static long restore_user_regs(struct pt_regs *regs,
664 struct mcontext __user *sr, int sig)
665{
666 long err;
667 unsigned int save_r2 = 0;
668 unsigned long msr;
669#ifdef CONFIG_VSX
670 int i;
671#endif
672
673 /*
674 * restore general registers but not including MSR or SOFTE. Also
675 * take care of keeping r2 (TLS) intact if not a signal
676 */
677 if (!sig)
678 save_r2 = (unsigned int)regs->gpr[2];
679 err = restore_general_regs(regs, sr);
680 regs->trap = 0;
681 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
682 if (!sig)
683 regs->gpr[2] = (unsigned long) save_r2;
684 if (err)
685 return 1;
686
687 /* if doing signal return, restore the previous little-endian mode */
688 if (sig)
689 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
690
691 /*
692 * Do this before updating the thread state in
693 * current->thread.fpr/vr/evr. That way, if we get preempted
694 * and another task grabs the FPU/Altivec/SPE, it won't be
695 * tempted to save the current CPU state into the thread_struct
696 * and corrupt what we are writing there.
697 */
698 discard_lazy_cpu_state();
699
700#ifdef CONFIG_ALTIVEC
701 /*
702 * Force the process to reload the altivec registers from
703 * current->thread when it next does altivec instructions
704 */
705 regs->msr &= ~MSR_VEC;
706 if (msr & MSR_VEC) {
707 /* restore altivec registers from the stack */
708 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
709 sizeof(sr->mc_vregs)))
710 return 1;
711 } else if (current->thread.used_vr)
712 memset(¤t->thread.vr_state, 0,
713 ELF_NVRREG * sizeof(vector128));
714
715 /* Always get VRSAVE back */
716 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
717 return 1;
718 if (cpu_has_feature(CPU_FTR_ALTIVEC))
719 mtspr(SPRN_VRSAVE, current->thread.vrsave);
720#endif /* CONFIG_ALTIVEC */
721 if (copy_fpr_from_user(current, &sr->mc_fregs))
722 return 1;
723
724#ifdef CONFIG_VSX
725 /*
726 * Force the process to reload the VSX registers from
727 * current->thread when it next does VSX instruction.
728 */
729 regs->msr &= ~MSR_VSX;
730 if (msr & MSR_VSX) {
731 /*
732 * Restore altivec registers from the stack to a local
733 * buffer, then write this out to the thread_struct
734 */
735 if (copy_vsx_from_user(current, &sr->mc_vsregs))
736 return 1;
737 } else if (current->thread.used_vsr)
738 for (i = 0; i < 32 ; i++)
739 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
740#endif /* CONFIG_VSX */
741 /*
742 * force the process to reload the FP registers from
743 * current->thread when it next does FP instructions
744 */
745 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
746
747#ifdef CONFIG_SPE
748 /* force the process to reload the spe registers from
749 current->thread when it next does spe instructions */
750 regs->msr &= ~MSR_SPE;
751 if (msr & MSR_SPE) {
752 /* restore spe registers from the stack */
753 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
754 ELF_NEVRREG * sizeof(u32)))
755 return 1;
756 } else if (current->thread.used_spe)
757 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
758
759 /* Always get SPEFSCR back */
760 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
761 return 1;
762#endif /* CONFIG_SPE */
763
764 return 0;
765}
766
767#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
768/*
769 * Restore the current user register values from the user stack, except for
770 * MSR, and recheckpoint the original checkpointed register state for processes
771 * in transactions.
772 */
773static long restore_tm_user_regs(struct pt_regs *regs,
774 struct mcontext __user *sr,
775 struct mcontext __user *tm_sr)
776{
777 long err;
778 unsigned long msr, msr_hi;
779#ifdef CONFIG_VSX
780 int i;
781#endif
782
783 /*
784 * restore general registers but not including MSR or SOFTE. Also
785 * take care of keeping r2 (TLS) intact if not a signal.
786 * See comment in signal_64.c:restore_tm_sigcontexts();
787 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
788 * were set by the signal delivery.
789 */
790 err = restore_general_regs(regs, tm_sr);
791 err |= restore_general_regs(¤t->thread.ckpt_regs, sr);
792
793 err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
794
795 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
796 if (err)
797 return 1;
798
799 /* Restore the previous little-endian mode */
800 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
801
802 /*
803 * Do this before updating the thread state in
804 * current->thread.fpr/vr/evr. That way, if we get preempted
805 * and another task grabs the FPU/Altivec/SPE, it won't be
806 * tempted to save the current CPU state into the thread_struct
807 * and corrupt what we are writing there.
808 */
809 discard_lazy_cpu_state();
810
811#ifdef CONFIG_ALTIVEC
812 regs->msr &= ~MSR_VEC;
813 if (msr & MSR_VEC) {
814 /* restore altivec registers from the stack */
815 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
816 sizeof(sr->mc_vregs)) ||
817 __copy_from_user(¤t->thread.transact_vr,
818 &tm_sr->mc_vregs,
819 sizeof(sr->mc_vregs)))
820 return 1;
821 } else if (current->thread.used_vr) {
822 memset(¤t->thread.vr_state, 0,
823 ELF_NVRREG * sizeof(vector128));
824 memset(¤t->thread.transact_vr, 0,
825 ELF_NVRREG * sizeof(vector128));
826 }
827
828 /* Always get VRSAVE back */
829 if (__get_user(current->thread.vrsave,
830 (u32 __user *)&sr->mc_vregs[32]) ||
831 __get_user(current->thread.transact_vrsave,
832 (u32 __user *)&tm_sr->mc_vregs[32]))
833 return 1;
834 if (cpu_has_feature(CPU_FTR_ALTIVEC))
835 mtspr(SPRN_VRSAVE, current->thread.vrsave);
836#endif /* CONFIG_ALTIVEC */
837
838 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
839
840 if (copy_fpr_from_user(current, &sr->mc_fregs) ||
841 copy_transact_fpr_from_user(current, &tm_sr->mc_fregs))
842 return 1;
843
844#ifdef CONFIG_VSX
845 regs->msr &= ~MSR_VSX;
846 if (msr & MSR_VSX) {
847 /*
848 * Restore altivec registers from the stack to a local
849 * buffer, then write this out to the thread_struct
850 */
851 if (copy_vsx_from_user(current, &sr->mc_vsregs) ||
852 copy_transact_vsx_from_user(current, &tm_sr->mc_vsregs))
853 return 1;
854 } else if (current->thread.used_vsr)
855 for (i = 0; i < 32 ; i++) {
856 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
857 current->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET] = 0;
858 }
859#endif /* CONFIG_VSX */
860
861#ifdef CONFIG_SPE
862 /* SPE regs are not checkpointed with TM, so this section is
863 * simply the same as in restore_user_regs().
864 */
865 regs->msr &= ~MSR_SPE;
866 if (msr & MSR_SPE) {
867 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
868 ELF_NEVRREG * sizeof(u32)))
869 return 1;
870 } else if (current->thread.used_spe)
871 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
872
873 /* Always get SPEFSCR back */
874 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
875 + ELF_NEVRREG))
876 return 1;
877#endif /* CONFIG_SPE */
878
879 /* Now, recheckpoint. This loads up all of the checkpointed (older)
880 * registers, including FP and V[S]Rs. After recheckpointing, the
881 * transactional versions should be loaded.
882 */
883 tm_enable();
884 /* Make sure the transaction is marked as failed */
885 current->thread.tm_texasr |= TEXASR_FS;
886 /* This loads the checkpointed FP/VEC state, if used */
887 tm_recheckpoint(¤t->thread, msr);
888 /* Get the top half of the MSR */
889 if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
890 return 1;
891 /* Pull in MSR TM from user context */
892 regs->msr = (regs->msr & ~MSR_TS_MASK) | ((msr_hi<<32) & MSR_TS_MASK);
893
894 /* This loads the speculative FP/VEC state, if used */
895 if (msr & MSR_FP) {
896 do_load_up_transact_fpu(¤t->thread);
897 regs->msr |= (MSR_FP | current->thread.fpexc_mode);
898 }
899#ifdef CONFIG_ALTIVEC
900 if (msr & MSR_VEC) {
901 do_load_up_transact_altivec(¤t->thread);
902 regs->msr |= MSR_VEC;
903 }
904#endif
905
906 return 0;
907}
908#endif
909
910#ifdef CONFIG_PPC64
911int copy_siginfo_to_user32(struct compat_siginfo __user *d, const siginfo_t *s)
912{
913 int err;
914
915 if (!access_ok (VERIFY_WRITE, d, sizeof(*d)))
916 return -EFAULT;
917
918 /* If you change siginfo_t structure, please be sure
919 * this code is fixed accordingly.
920 * It should never copy any pad contained in the structure
921 * to avoid security leaks, but must copy the generic
922 * 3 ints plus the relevant union member.
923 * This routine must convert siginfo from 64bit to 32bit as well
924 * at the same time.
925 */
926 err = __put_user(s->si_signo, &d->si_signo);
927 err |= __put_user(s->si_errno, &d->si_errno);
928 err |= __put_user((short)s->si_code, &d->si_code);
929 if (s->si_code < 0)
930 err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad,
931 SI_PAD_SIZE32);
932 else switch(s->si_code >> 16) {
933 case __SI_CHLD >> 16:
934 err |= __put_user(s->si_pid, &d->si_pid);
935 err |= __put_user(s->si_uid, &d->si_uid);
936 err |= __put_user(s->si_utime, &d->si_utime);
937 err |= __put_user(s->si_stime, &d->si_stime);
938 err |= __put_user(s->si_status, &d->si_status);
939 break;
940 case __SI_FAULT >> 16:
941 err |= __put_user((unsigned int)(unsigned long)s->si_addr,
942 &d->si_addr);
943 break;
944 case __SI_POLL >> 16:
945 err |= __put_user(s->si_band, &d->si_band);
946 err |= __put_user(s->si_fd, &d->si_fd);
947 break;
948 case __SI_TIMER >> 16:
949 err |= __put_user(s->si_tid, &d->si_tid);
950 err |= __put_user(s->si_overrun, &d->si_overrun);
951 err |= __put_user(s->si_int, &d->si_int);
952 break;
953 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
954 case __SI_MESGQ >> 16:
955 err |= __put_user(s->si_int, &d->si_int);
956 /* fallthrough */
957 case __SI_KILL >> 16:
958 default:
959 err |= __put_user(s->si_pid, &d->si_pid);
960 err |= __put_user(s->si_uid, &d->si_uid);
961 break;
962 }
963 return err;
964}
965
966#define copy_siginfo_to_user copy_siginfo_to_user32
967
968int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from)
969{
970 memset(to, 0, sizeof *to);
971
972 if (copy_from_user(to, from, 3*sizeof(int)) ||
973 copy_from_user(to->_sifields._pad,
974 from->_sifields._pad, SI_PAD_SIZE32))
975 return -EFAULT;
976
977 return 0;
978}
979#endif /* CONFIG_PPC64 */
980
981/*
982 * Set up a signal frame for a "real-time" signal handler
983 * (one which gets siginfo).
984 */
985int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
986 siginfo_t *info, sigset_t *oldset,
987 struct pt_regs *regs)
988{
989 struct rt_sigframe __user *rt_sf;
990 struct mcontext __user *frame;
991 struct mcontext __user *tm_frame = NULL;
992 void __user *addr;
993 unsigned long newsp = 0;
994 int sigret;
995 unsigned long tramp;
996
997 /* Set up Signal Frame */
998 /* Put a Real Time Context onto stack */
999 rt_sf = get_sigframe(ka, get_tm_stackpointer(regs), sizeof(*rt_sf), 1);
1000 addr = rt_sf;
1001 if (unlikely(rt_sf == NULL))
1002 goto badframe;
1003
1004 /* Put the siginfo & fill in most of the ucontext */
1005 if (copy_siginfo_to_user(&rt_sf->info, info)
1006 || __put_user(0, &rt_sf->uc.uc_flags)
1007 || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
1008 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
1009 &rt_sf->uc.uc_regs)
1010 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
1011 goto badframe;
1012
1013 /* Save user registers on the stack */
1014 frame = &rt_sf->uc.uc_mcontext;
1015 addr = frame;
1016 if (vdso32_rt_sigtramp && current->mm->context.vdso_base) {
1017 sigret = 0;
1018 tramp = current->mm->context.vdso_base + vdso32_rt_sigtramp;
1019 } else {
1020 sigret = __NR_rt_sigreturn;
1021 tramp = (unsigned long) frame->tramp;
1022 }
1023
1024#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1025 tm_frame = &rt_sf->uc_transact.uc_mcontext;
1026 if (MSR_TM_ACTIVE(regs->msr)) {
1027 if (__put_user((unsigned long)&rt_sf->uc_transact,
1028 &rt_sf->uc.uc_link) ||
1029 __put_user((unsigned long)tm_frame,
1030 &rt_sf->uc_transact.uc_regs))
1031 goto badframe;
1032 if (save_tm_user_regs(regs, frame, tm_frame, sigret))
1033 goto badframe;
1034 }
1035 else
1036#endif
1037 {
1038 if (__put_user(0, &rt_sf->uc.uc_link))
1039 goto badframe;
1040 if (save_user_regs(regs, frame, tm_frame, sigret, 1))
1041 goto badframe;
1042 }
1043 regs->link = tramp;
1044
1045 current->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
1046
1047 /* create a stack frame for the caller of the handler */
1048 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
1049 addr = (void __user *)regs->gpr[1];
1050 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1051 goto badframe;
1052
1053 /* Fill registers for signal handler */
1054 regs->gpr[1] = newsp;
1055 regs->gpr[3] = sig;
1056 regs->gpr[4] = (unsigned long) &rt_sf->info;
1057 regs->gpr[5] = (unsigned long) &rt_sf->uc;
1058 regs->gpr[6] = (unsigned long) rt_sf;
1059 regs->nip = (unsigned long) ka->sa.sa_handler;
1060 /* enter the signal handler in native-endian mode */
1061 regs->msr &= ~MSR_LE;
1062 regs->msr |= (MSR_KERNEL & MSR_LE);
1063 return 1;
1064
1065badframe:
1066#ifdef DEBUG_SIG
1067 printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n",
1068 regs, frame, newsp);
1069#endif
1070 if (show_unhandled_signals)
1071 printk_ratelimited(KERN_INFO
1072 "%s[%d]: bad frame in handle_rt_signal32: "
1073 "%p nip %08lx lr %08lx\n",
1074 current->comm, current->pid,
1075 addr, regs->nip, regs->link);
1076
1077 force_sigsegv(sig, current);
1078 return 0;
1079}
1080
1081static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
1082{
1083 sigset_t set;
1084 struct mcontext __user *mcp;
1085
1086 if (get_sigset_t(&set, &ucp->uc_sigmask))
1087 return -EFAULT;
1088#ifdef CONFIG_PPC64
1089 {
1090 u32 cmcp;
1091
1092 if (__get_user(cmcp, &ucp->uc_regs))
1093 return -EFAULT;
1094 mcp = (struct mcontext __user *)(u64)cmcp;
1095 /* no need to check access_ok(mcp), since mcp < 4GB */
1096 }
1097#else
1098 if (__get_user(mcp, &ucp->uc_regs))
1099 return -EFAULT;
1100 if (!access_ok(VERIFY_READ, mcp, sizeof(*mcp)))
1101 return -EFAULT;
1102#endif
1103 set_current_blocked(&set);
1104 if (restore_user_regs(regs, mcp, sig))
1105 return -EFAULT;
1106
1107 return 0;
1108}
1109
1110#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1111static int do_setcontext_tm(struct ucontext __user *ucp,
1112 struct ucontext __user *tm_ucp,
1113 struct pt_regs *regs)
1114{
1115 sigset_t set;
1116 struct mcontext __user *mcp;
1117 struct mcontext __user *tm_mcp;
1118 u32 cmcp;
1119 u32 tm_cmcp;
1120
1121 if (get_sigset_t(&set, &ucp->uc_sigmask))
1122 return -EFAULT;
1123
1124 if (__get_user(cmcp, &ucp->uc_regs) ||
1125 __get_user(tm_cmcp, &tm_ucp->uc_regs))
1126 return -EFAULT;
1127 mcp = (struct mcontext __user *)(u64)cmcp;
1128 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
1129 /* no need to check access_ok(mcp), since mcp < 4GB */
1130
1131 set_current_blocked(&set);
1132 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1133 return -EFAULT;
1134
1135 return 0;
1136}
1137#endif
1138
1139long sys_swapcontext(struct ucontext __user *old_ctx,
1140 struct ucontext __user *new_ctx,
1141 int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
1142{
1143 unsigned char tmp;
1144 int ctx_has_vsx_region = 0;
1145
1146#ifdef CONFIG_PPC64
1147 unsigned long new_msr = 0;
1148
1149 if (new_ctx) {
1150 struct mcontext __user *mcp;
1151 u32 cmcp;
1152
1153 /*
1154 * Get pointer to the real mcontext. No need for
1155 * access_ok since we are dealing with compat
1156 * pointers.
1157 */
1158 if (__get_user(cmcp, &new_ctx->uc_regs))
1159 return -EFAULT;
1160 mcp = (struct mcontext __user *)(u64)cmcp;
1161 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
1162 return -EFAULT;
1163 }
1164 /*
1165 * Check that the context is not smaller than the original
1166 * size (with VMX but without VSX)
1167 */
1168 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
1169 return -EINVAL;
1170 /*
1171 * If the new context state sets the MSR VSX bits but
1172 * it doesn't provide VSX state.
1173 */
1174 if ((ctx_size < sizeof(struct ucontext)) &&
1175 (new_msr & MSR_VSX))
1176 return -EINVAL;
1177 /* Does the context have enough room to store VSX data? */
1178 if (ctx_size >= sizeof(struct ucontext))
1179 ctx_has_vsx_region = 1;
1180#else
1181 /* Context size is for future use. Right now, we only make sure
1182 * we are passed something we understand
1183 */
1184 if (ctx_size < sizeof(struct ucontext))
1185 return -EINVAL;
1186#endif
1187 if (old_ctx != NULL) {
1188 struct mcontext __user *mctx;
1189
1190 /*
1191 * old_ctx might not be 16-byte aligned, in which
1192 * case old_ctx->uc_mcontext won't be either.
1193 * Because we have the old_ctx->uc_pad2 field
1194 * before old_ctx->uc_mcontext, we need to round down
1195 * from &old_ctx->uc_mcontext to a 16-byte boundary.
1196 */
1197 mctx = (struct mcontext __user *)
1198 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
1199 if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size)
1200 || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
1201 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
1202 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
1203 return -EFAULT;
1204 }
1205 if (new_ctx == NULL)
1206 return 0;
1207 if (!access_ok(VERIFY_READ, new_ctx, ctx_size)
1208 || __get_user(tmp, (u8 __user *) new_ctx)
1209 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
1210 return -EFAULT;
1211
1212 /*
1213 * If we get a fault copying the context into the kernel's
1214 * image of the user's registers, we can't just return -EFAULT
1215 * because the user's registers will be corrupted. For instance
1216 * the NIP value may have been updated but not some of the
1217 * other registers. Given that we have done the access_ok
1218 * and successfully read the first and last bytes of the region
1219 * above, this should only happen in an out-of-memory situation
1220 * or if another thread unmaps the region containing the context.
1221 * We kill the task with a SIGSEGV in this situation.
1222 */
1223 if (do_setcontext(new_ctx, regs, 0))
1224 do_exit(SIGSEGV);
1225
1226 set_thread_flag(TIF_RESTOREALL);
1227 return 0;
1228}
1229
1230long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1231 struct pt_regs *regs)
1232{
1233 struct rt_sigframe __user *rt_sf;
1234#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1235 struct ucontext __user *uc_transact;
1236 unsigned long msr_hi;
1237 unsigned long tmp;
1238 int tm_restore = 0;
1239#endif
1240 /* Always make any pending restarted system calls return -EINTR */
1241 current_thread_info()->restart_block.fn = do_no_restart_syscall;
1242
1243 rt_sf = (struct rt_sigframe __user *)
1244 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1245 if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
1246 goto bad;
1247#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1248 if (__get_user(tmp, &rt_sf->uc.uc_link))
1249 goto bad;
1250 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1251 if (uc_transact) {
1252 u32 cmcp;
1253 struct mcontext __user *mcp;
1254
1255 if (__get_user(cmcp, &uc_transact->uc_regs))
1256 return -EFAULT;
1257 mcp = (struct mcontext __user *)(u64)cmcp;
1258 /* The top 32 bits of the MSR are stashed in the transactional
1259 * ucontext. */
1260 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1261 goto bad;
1262
1263 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1264 /* We only recheckpoint on return if we're
1265 * transaction.
1266 */
1267 tm_restore = 1;
1268 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1269 goto bad;
1270 }
1271 }
1272 if (!tm_restore)
1273 /* Fall through, for non-TM restore */
1274#endif
1275 if (do_setcontext(&rt_sf->uc, regs, 1))
1276 goto bad;
1277
1278 /*
1279 * It's not clear whether or why it is desirable to save the
1280 * sigaltstack setting on signal delivery and restore it on
1281 * signal return. But other architectures do this and we have
1282 * always done it up until now so it is probably better not to
1283 * change it. -- paulus
1284 */
1285#ifdef CONFIG_PPC64
1286 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1287 goto bad;
1288#else
1289 if (restore_altstack(&rt_sf->uc.uc_stack))
1290 goto bad;
1291#endif
1292 set_thread_flag(TIF_RESTOREALL);
1293 return 0;
1294
1295 bad:
1296 if (show_unhandled_signals)
1297 printk_ratelimited(KERN_INFO
1298 "%s[%d]: bad frame in sys_rt_sigreturn: "
1299 "%p nip %08lx lr %08lx\n",
1300 current->comm, current->pid,
1301 rt_sf, regs->nip, regs->link);
1302
1303 force_sig(SIGSEGV, current);
1304 return 0;
1305}
1306
1307#ifdef CONFIG_PPC32
1308int sys_debug_setcontext(struct ucontext __user *ctx,
1309 int ndbg, struct sig_dbg_op __user *dbg,
1310 int r6, int r7, int r8,
1311 struct pt_regs *regs)
1312{
1313 struct sig_dbg_op op;
1314 int i;
1315 unsigned char tmp;
1316 unsigned long new_msr = regs->msr;
1317#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1318 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1319#endif
1320
1321 for (i=0; i<ndbg; i++) {
1322 if (copy_from_user(&op, dbg + i, sizeof(op)))
1323 return -EFAULT;
1324 switch (op.dbg_type) {
1325 case SIG_DBG_SINGLE_STEPPING:
1326#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1327 if (op.dbg_value) {
1328 new_msr |= MSR_DE;
1329 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1330 } else {
1331 new_dbcr0 &= ~DBCR0_IC;
1332 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1333 current->thread.debug.dbcr1)) {
1334 new_msr &= ~MSR_DE;
1335 new_dbcr0 &= ~DBCR0_IDM;
1336 }
1337 }
1338#else
1339 if (op.dbg_value)
1340 new_msr |= MSR_SE;
1341 else
1342 new_msr &= ~MSR_SE;
1343#endif
1344 break;
1345 case SIG_DBG_BRANCH_TRACING:
1346#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1347 return -EINVAL;
1348#else
1349 if (op.dbg_value)
1350 new_msr |= MSR_BE;
1351 else
1352 new_msr &= ~MSR_BE;
1353#endif
1354 break;
1355
1356 default:
1357 return -EINVAL;
1358 }
1359 }
1360
1361 /* We wait until here to actually install the values in the
1362 registers so if we fail in the above loop, it will not
1363 affect the contents of these registers. After this point,
1364 failure is a problem, anyway, and it's very unlikely unless
1365 the user is really doing something wrong. */
1366 regs->msr = new_msr;
1367#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1368 current->thread.debug.dbcr0 = new_dbcr0;
1369#endif
1370
1371 if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx))
1372 || __get_user(tmp, (u8 __user *) ctx)
1373 || __get_user(tmp, (u8 __user *) (ctx + 1) - 1))
1374 return -EFAULT;
1375
1376 /*
1377 * If we get a fault copying the context into the kernel's
1378 * image of the user's registers, we can't just return -EFAULT
1379 * because the user's registers will be corrupted. For instance
1380 * the NIP value may have been updated but not some of the
1381 * other registers. Given that we have done the access_ok
1382 * and successfully read the first and last bytes of the region
1383 * above, this should only happen in an out-of-memory situation
1384 * or if another thread unmaps the region containing the context.
1385 * We kill the task with a SIGSEGV in this situation.
1386 */
1387 if (do_setcontext(ctx, regs, 1)) {
1388 if (show_unhandled_signals)
1389 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1390 "sys_debug_setcontext: %p nip %08lx "
1391 "lr %08lx\n",
1392 current->comm, current->pid,
1393 ctx, regs->nip, regs->link);
1394
1395 force_sig(SIGSEGV, current);
1396 goto out;
1397 }
1398
1399 /*
1400 * It's not clear whether or why it is desirable to save the
1401 * sigaltstack setting on signal delivery and restore it on
1402 * signal return. But other architectures do this and we have
1403 * always done it up until now so it is probably better not to
1404 * change it. -- paulus
1405 */
1406 restore_altstack(&ctx->uc_stack);
1407
1408 set_thread_flag(TIF_RESTOREALL);
1409 out:
1410 return 0;
1411}
1412#endif
1413
1414/*
1415 * OK, we're invoking a handler
1416 */
1417int handle_signal32(unsigned long sig, struct k_sigaction *ka,
1418 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
1419{
1420 struct sigcontext __user *sc;
1421 struct sigframe __user *frame;
1422 struct mcontext __user *tm_mctx = NULL;
1423 unsigned long newsp = 0;
1424 int sigret;
1425 unsigned long tramp;
1426
1427 /* Set up Signal Frame */
1428 frame = get_sigframe(ka, get_tm_stackpointer(regs), sizeof(*frame), 1);
1429 if (unlikely(frame == NULL))
1430 goto badframe;
1431 sc = (struct sigcontext __user *) &frame->sctx;
1432
1433#if _NSIG != 64
1434#error "Please adjust handle_signal()"
1435#endif
1436 if (__put_user(to_user_ptr(ka->sa.sa_handler), &sc->handler)
1437 || __put_user(oldset->sig[0], &sc->oldmask)
1438#ifdef CONFIG_PPC64
1439 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1440#else
1441 || __put_user(oldset->sig[1], &sc->_unused[3])
1442#endif
1443 || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1444 || __put_user(sig, &sc->signal))
1445 goto badframe;
1446
1447 if (vdso32_sigtramp && current->mm->context.vdso_base) {
1448 sigret = 0;
1449 tramp = current->mm->context.vdso_base + vdso32_sigtramp;
1450 } else {
1451 sigret = __NR_sigreturn;
1452 tramp = (unsigned long) frame->mctx.tramp;
1453 }
1454
1455#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1456 tm_mctx = &frame->mctx_transact;
1457 if (MSR_TM_ACTIVE(regs->msr)) {
1458 if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
1459 sigret))
1460 goto badframe;
1461 }
1462 else
1463#endif
1464 {
1465 if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
1466 goto badframe;
1467 }
1468
1469 regs->link = tramp;
1470
1471 current->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
1472
1473 /* create a stack frame for the caller of the handler */
1474 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1475 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1476 goto badframe;
1477
1478 regs->gpr[1] = newsp;
1479 regs->gpr[3] = sig;
1480 regs->gpr[4] = (unsigned long) sc;
1481 regs->nip = (unsigned long) ka->sa.sa_handler;
1482 /* enter the signal handler in big-endian mode */
1483 regs->msr &= ~MSR_LE;
1484 return 1;
1485
1486badframe:
1487#ifdef DEBUG_SIG
1488 printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n",
1489 regs, frame, newsp);
1490#endif
1491 if (show_unhandled_signals)
1492 printk_ratelimited(KERN_INFO
1493 "%s[%d]: bad frame in handle_signal32: "
1494 "%p nip %08lx lr %08lx\n",
1495 current->comm, current->pid,
1496 frame, regs->nip, regs->link);
1497
1498 force_sigsegv(sig, current);
1499 return 0;
1500}
1501
1502/*
1503 * Do a signal return; undo the signal stack.
1504 */
1505long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1506 struct pt_regs *regs)
1507{
1508 struct sigframe __user *sf;
1509 struct sigcontext __user *sc;
1510 struct sigcontext sigctx;
1511 struct mcontext __user *sr;
1512 void __user *addr;
1513 sigset_t set;
1514#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1515 struct mcontext __user *mcp, *tm_mcp;
1516 unsigned long msr_hi;
1517#endif
1518
1519 /* Always make any pending restarted system calls return -EINTR */
1520 current_thread_info()->restart_block.fn = do_no_restart_syscall;
1521
1522 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1523 sc = &sf->sctx;
1524 addr = sc;
1525 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1526 goto badframe;
1527
1528#ifdef CONFIG_PPC64
1529 /*
1530 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1531 * unused part of the signal stackframe
1532 */
1533 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1534#else
1535 set.sig[0] = sigctx.oldmask;
1536 set.sig[1] = sigctx._unused[3];
1537#endif
1538 set_current_blocked(&set);
1539
1540#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1541 mcp = (struct mcontext __user *)&sf->mctx;
1542 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1543 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1544 goto badframe;
1545 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1546 if (!cpu_has_feature(CPU_FTR_TM))
1547 goto badframe;
1548 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1549 goto badframe;
1550 } else
1551#endif
1552 {
1553 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1554 addr = sr;
1555 if (!access_ok(VERIFY_READ, sr, sizeof(*sr))
1556 || restore_user_regs(regs, sr, 1))
1557 goto badframe;
1558 }
1559
1560 set_thread_flag(TIF_RESTOREALL);
1561 return 0;
1562
1563badframe:
1564 if (show_unhandled_signals)
1565 printk_ratelimited(KERN_INFO
1566 "%s[%d]: bad frame in sys_sigreturn: "
1567 "%p nip %08lx lr %08lx\n",
1568 current->comm, current->pid,
1569 addr, regs->nip, regs->link);
1570
1571 force_sig(SIGSEGV, current);
1572 return 0;
1573}