3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
5 * Derived from "arch/i386/kernel/signal.c"
6 * Copyright (C) 1991, 1992 Linus Torvalds
7 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
15 #include <linux/sched.h>
17 #include <linux/smp.h>
18 #include <linux/kernel.h>
19 #include <linux/signal.h>
20 #include <linux/errno.h>
21 #include <linux/wait.h>
22 #include <linux/unistd.h>
23 #include <linux/stddef.h>
24 #include <linux/elf.h>
25 #include <linux/ptrace.h>
26 #include <linux/ratelimit.h>
28 #include <asm/sigcontext.h>
29 #include <asm/ucontext.h>
30 #include <asm/uaccess.h>
31 #include <asm/pgtable.h>
32 #include <asm/unistd.h>
33 #include <asm/cacheflush.h>
34 #include <asm/syscalls.h>
36 #include <asm/switch_to.h>
38 #include <asm/asm-prototypes.h>
43 #define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
44 #define FP_REGS_SIZE sizeof(elf_fpregset_t)
46 #define TRAMP_TRACEBACK 3
50 * When we have signals to deliver, we set up on the user stack,
51 * going down from the original stack pointer:
52 * 1) a rt_sigframe struct which contains the ucontext
53 * 2) a gap of __SIGNAL_FRAMESIZE bytes which acts as a dummy caller
54 * frame for the signal handler.
58 /* sys_rt_sigreturn requires the ucontext be the first field */
60 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
61 struct ucontext uc_transact;
63 unsigned long _unused[2];
64 unsigned int tramp[TRAMP_SIZE];
65 struct siginfo __user *pinfo;
68 /* New 64 bit little-endian ABI allows redzone of 512 bytes below sp */
69 char abigap[USER_REDZONE_SIZE];
70 } __attribute__ ((aligned (16)));
72 static const char fmt32[] = KERN_INFO \
73 "%s[%d]: bad frame in %s: %08lx nip %08lx lr %08lx\n";
74 static const char fmt64[] = KERN_INFO \
75 "%s[%d]: bad frame in %s: %016lx nip %016lx lr %016lx\n";
78 * This computes a quad word aligned pointer inside the vmx_reserve array
79 * element. For historical reasons sigcontext might not be quad word aligned,
80 * but the location we write the VMX regs to must be. See the comment in
81 * sigcontext for more detail.
84 static elf_vrreg_t __user *sigcontext_vmx_regs(struct sigcontext __user *sc)
86 return (elf_vrreg_t __user *) (((unsigned long)sc->vmx_reserve + 15) & ~0xful);
91 * Set up the sigcontext for the signal frame.
94 static long setup_sigcontext(struct sigcontext __user *sc,
95 struct task_struct *tsk, int signr, sigset_t *set,
96 unsigned long handler, int ctx_has_vsx_region)
98 /* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
99 * process never used altivec yet (MSR_VEC is zero in pt_regs of
100 * the context). This is very important because we must ensure we
101 * don't lose the VRSAVE content that may have been set prior to
102 * the process doing its first vector operation
103 * Userland shall check AT_HWCAP to know whether it can rely on the
104 * v_regs pointer or not
106 #ifdef CONFIG_ALTIVEC
107 elf_vrreg_t __user *v_regs = sigcontext_vmx_regs(sc);
108 unsigned long vrsave;
110 struct pt_regs *regs = tsk->thread.regs;
111 unsigned long msr = regs->msr;
114 BUG_ON(tsk != current);
116 #ifdef CONFIG_ALTIVEC
117 err |= __put_user(v_regs, &sc->v_regs);
119 /* save altivec registers */
120 if (tsk->thread.used_vr) {
121 flush_altivec_to_thread(tsk);
122 /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
123 err |= __copy_to_user(v_regs, &tsk->thread.vr_state,
124 33 * sizeof(vector128));
125 /* set MSR_VEC in the MSR value in the frame to indicate that sc->v_reg)
126 * contains valid data.
130 /* We always copy to/from vrsave, it's 0 if we don't have or don't
134 if (cpu_has_feature(CPU_FTR_ALTIVEC)) {
135 vrsave = mfspr(SPRN_VRSAVE);
136 tsk->thread.vrsave = vrsave;
139 err |= __put_user(vrsave, (u32 __user *)&v_regs[33]);
140 #else /* CONFIG_ALTIVEC */
141 err |= __put_user(0, &sc->v_regs);
142 #endif /* CONFIG_ALTIVEC */
143 flush_fp_to_thread(tsk);
144 /* copy fpr regs and fpscr */
145 err |= copy_fpr_to_user(&sc->fp_regs, tsk);
148 * Clear the MSR VSX bit to indicate there is no valid state attached
149 * to this context, except in the specific case below where we set it.
154 * Copy VSX low doubleword to local buffer for formatting,
155 * then out to userspace. Update v_regs to point after the
158 if (tsk->thread.used_vsr && ctx_has_vsx_region) {
159 flush_vsx_to_thread(tsk);
160 v_regs += ELF_NVRREG;
161 err |= copy_vsx_to_user(v_regs, tsk);
162 /* set MSR_VSX in the MSR value in the frame to
163 * indicate that sc->vs_reg) contains valid data.
167 #endif /* CONFIG_VSX */
168 err |= __put_user(&sc->gp_regs, &sc->regs);
169 WARN_ON(!FULL_REGS(regs));
170 err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE);
171 err |= __put_user(msr, &sc->gp_regs[PT_MSR]);
172 err |= __put_user(signr, &sc->signal);
173 err |= __put_user(handler, &sc->handler);
175 err |= __put_user(set->sig[0], &sc->oldmask);
180 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
182 * As above, but Transactional Memory is in use, so deliver sigcontexts
183 * containing checkpointed and transactional register states.
185 * To do this, we treclaim (done before entering here) to gather both sets of
186 * registers and set up the 'normal' sigcontext registers with rolled-back
187 * register values such that a simple signal handler sees a correct
188 * checkpointed register state. If interested, a TM-aware sighandler can
189 * examine the transactional registers in the 2nd sigcontext to determine the
190 * real origin of the signal.
192 static long setup_tm_sigcontexts(struct sigcontext __user *sc,
193 struct sigcontext __user *tm_sc,
194 struct task_struct *tsk,
195 int signr, sigset_t *set, unsigned long handler)
197 /* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
198 * process never used altivec yet (MSR_VEC is zero in pt_regs of
199 * the context). This is very important because we must ensure we
200 * don't lose the VRSAVE content that may have been set prior to
201 * the process doing its first vector operation
202 * Userland shall check AT_HWCAP to know wether it can rely on the
203 * v_regs pointer or not.
205 #ifdef CONFIG_ALTIVEC
206 elf_vrreg_t __user *v_regs = sigcontext_vmx_regs(sc);
207 elf_vrreg_t __user *tm_v_regs = sigcontext_vmx_regs(tm_sc);
209 struct pt_regs *regs = tsk->thread.regs;
210 unsigned long msr = tsk->thread.ckpt_regs.msr;
213 BUG_ON(tsk != current);
215 BUG_ON(!MSR_TM_ACTIVE(regs->msr));
217 /* Remove TM bits from thread's MSR. The MSR in the sigcontext
218 * just indicates to userland that we were doing a transaction, but we
219 * don't want to return in transactional state. This also ensures
220 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
222 regs->msr &= ~MSR_TS_MASK;
224 flush_fp_to_thread(tsk);
226 #ifdef CONFIG_ALTIVEC
227 err |= __put_user(v_regs, &sc->v_regs);
228 err |= __put_user(tm_v_regs, &tm_sc->v_regs);
230 /* save altivec registers */
231 if (tsk->thread.used_vr) {
232 flush_altivec_to_thread(tsk);
233 /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
234 err |= __copy_to_user(v_regs, &tsk->thread.vr_state,
235 33 * sizeof(vector128));
236 /* If VEC was enabled there are transactional VRs valid too,
237 * else they're a copy of the checkpointed VRs.
240 err |= __copy_to_user(tm_v_regs,
241 &tsk->thread.transact_vr,
242 33 * sizeof(vector128));
244 err |= __copy_to_user(tm_v_regs,
245 &tsk->thread.vr_state,
246 33 * sizeof(vector128));
248 /* set MSR_VEC in the MSR value in the frame to indicate
249 * that sc->v_reg contains valid data.
253 /* We always copy to/from vrsave, it's 0 if we don't have or don't
256 if (cpu_has_feature(CPU_FTR_ALTIVEC))
257 tsk->thread.vrsave = mfspr(SPRN_VRSAVE);
258 err |= __put_user(tsk->thread.vrsave, (u32 __user *)&v_regs[33]);
260 err |= __put_user(tsk->thread.transact_vrsave,
261 (u32 __user *)&tm_v_regs[33]);
263 err |= __put_user(tsk->thread.vrsave,
264 (u32 __user *)&tm_v_regs[33]);
266 #else /* CONFIG_ALTIVEC */
267 err |= __put_user(0, &sc->v_regs);
268 err |= __put_user(0, &tm_sc->v_regs);
269 #endif /* CONFIG_ALTIVEC */
271 /* copy fpr regs and fpscr */
272 err |= copy_fpr_to_user(&sc->fp_regs, tsk);
274 err |= copy_transact_fpr_to_user(&tm_sc->fp_regs, tsk);
276 err |= copy_fpr_to_user(&tm_sc->fp_regs, tsk);
280 * Copy VSX low doubleword to local buffer for formatting,
281 * then out to userspace. Update v_regs to point after the
284 if (tsk->thread.used_vsr) {
285 flush_vsx_to_thread(tsk);
286 v_regs += ELF_NVRREG;
287 tm_v_regs += ELF_NVRREG;
289 err |= copy_vsx_to_user(v_regs, tsk);
292 err |= copy_transact_vsx_to_user(tm_v_regs, tsk);
294 err |= copy_vsx_to_user(tm_v_regs, tsk);
296 /* set MSR_VSX in the MSR value in the frame to
297 * indicate that sc->vs_reg) contains valid data.
301 #endif /* CONFIG_VSX */
303 err |= __put_user(&sc->gp_regs, &sc->regs);
304 err |= __put_user(&tm_sc->gp_regs, &tm_sc->regs);
305 WARN_ON(!FULL_REGS(regs));
306 err |= __copy_to_user(&tm_sc->gp_regs, regs, GP_REGS_SIZE);
307 err |= __copy_to_user(&sc->gp_regs,
308 &tsk->thread.ckpt_regs, GP_REGS_SIZE);
309 err |= __put_user(msr, &tm_sc->gp_regs[PT_MSR]);
310 err |= __put_user(msr, &sc->gp_regs[PT_MSR]);
311 err |= __put_user(signr, &sc->signal);
312 err |= __put_user(handler, &sc->handler);
314 err |= __put_user(set->sig[0], &sc->oldmask);
321 * Restore the sigcontext from the signal frame.
324 static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
325 struct sigcontext __user *sc)
327 #ifdef CONFIG_ALTIVEC
328 elf_vrreg_t __user *v_regs;
330 unsigned long err = 0;
331 unsigned long save_r13 = 0;
333 struct pt_regs *regs = tsk->thread.regs;
338 BUG_ON(tsk != current);
340 /* If this is not a signal return, we preserve the TLS in r13 */
342 save_r13 = regs->gpr[13];
345 err |= __copy_from_user(regs->gpr, sc->gp_regs, sizeof(regs->gpr));
346 err |= __get_user(regs->nip, &sc->gp_regs[PT_NIP]);
347 /* get MSR separately, transfer the LE bit if doing signal return */
348 err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
350 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
351 err |= __get_user(regs->orig_gpr3, &sc->gp_regs[PT_ORIG_R3]);
352 err |= __get_user(regs->ctr, &sc->gp_regs[PT_CTR]);
353 err |= __get_user(regs->link, &sc->gp_regs[PT_LNK]);
354 err |= __get_user(regs->xer, &sc->gp_regs[PT_XER]);
355 err |= __get_user(regs->ccr, &sc->gp_regs[PT_CCR]);
358 err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
359 err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
360 err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
363 regs->gpr[13] = save_r13;
365 err |= __get_user(set->sig[0], &sc->oldmask);
368 * Force reload of FP/VEC.
369 * This has to be done before copying stuff into tsk->thread.fpr/vr
370 * for the reasons explained in the previous comment.
372 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
374 #ifdef CONFIG_ALTIVEC
375 err |= __get_user(v_regs, &sc->v_regs);
378 if (v_regs && !access_ok(VERIFY_READ, v_regs, 34 * sizeof(vector128)))
380 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
381 if (v_regs != NULL && (msr & MSR_VEC) != 0) {
382 err |= __copy_from_user(&tsk->thread.vr_state, v_regs,
383 33 * sizeof(vector128));
384 tsk->thread.used_vr = true;
385 } else if (tsk->thread.used_vr) {
386 memset(&tsk->thread.vr_state, 0, 33 * sizeof(vector128));
388 /* Always get VRSAVE back */
390 err |= __get_user(tsk->thread.vrsave, (u32 __user *)&v_regs[33]);
392 tsk->thread.vrsave = 0;
393 if (cpu_has_feature(CPU_FTR_ALTIVEC))
394 mtspr(SPRN_VRSAVE, tsk->thread.vrsave);
395 #endif /* CONFIG_ALTIVEC */
396 /* restore floating point */
397 err |= copy_fpr_from_user(tsk, &sc->fp_regs);
400 * Get additional VSX data. Update v_regs to point after the
401 * VMX data. Copy VSX low doubleword from userspace to local
402 * buffer for formatting, then into the taskstruct.
404 v_regs += ELF_NVRREG;
405 if ((msr & MSR_VSX) != 0) {
406 err |= copy_vsx_from_user(tsk, v_regs);
407 tsk->thread.used_vsr = true;
409 for (i = 0; i < 32 ; i++)
410 tsk->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
416 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
418 * Restore the two sigcontexts from the frame of a transactional processes.
421 static long restore_tm_sigcontexts(struct task_struct *tsk,
422 struct sigcontext __user *sc,
423 struct sigcontext __user *tm_sc)
425 #ifdef CONFIG_ALTIVEC
426 elf_vrreg_t __user *v_regs, *tm_v_regs;
428 unsigned long err = 0;
430 struct pt_regs *regs = tsk->thread.regs;
435 BUG_ON(tsk != current);
438 err |= __copy_from_user(regs->gpr, tm_sc->gp_regs, sizeof(regs->gpr));
439 err |= __copy_from_user(&tsk->thread.ckpt_regs, sc->gp_regs,
443 * TFHAR is restored from the checkpointed 'wound-back' ucontext's NIP.
444 * TEXASR was set by the signal delivery reclaim, as was TFIAR.
445 * Users doing anything abhorrent like thread-switching w/ signals for
446 * TM-Suspended code will have to back TEXASR/TFIAR up themselves.
447 * For the case of getting a signal and simply returning from it,
448 * we don't need to re-copy them here.
450 err |= __get_user(regs->nip, &tm_sc->gp_regs[PT_NIP]);
451 err |= __get_user(tsk->thread.tm_tfhar, &sc->gp_regs[PT_NIP]);
453 /* get MSR separately, transfer the LE bit if doing signal return */
454 err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
455 /* Don't allow reserved mode. */
456 if (MSR_TM_RESV(msr))
459 /* pull in MSR TM from user context */
460 regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr & MSR_TS_MASK);
462 /* pull in MSR LE from user context */
463 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
465 /* The following non-GPR non-FPR non-VR state is also checkpointed: */
466 err |= __get_user(regs->ctr, &tm_sc->gp_regs[PT_CTR]);
467 err |= __get_user(regs->link, &tm_sc->gp_regs[PT_LNK]);
468 err |= __get_user(regs->xer, &tm_sc->gp_regs[PT_XER]);
469 err |= __get_user(regs->ccr, &tm_sc->gp_regs[PT_CCR]);
470 err |= __get_user(tsk->thread.ckpt_regs.ctr,
471 &sc->gp_regs[PT_CTR]);
472 err |= __get_user(tsk->thread.ckpt_regs.link,
473 &sc->gp_regs[PT_LNK]);
474 err |= __get_user(tsk->thread.ckpt_regs.xer,
475 &sc->gp_regs[PT_XER]);
476 err |= __get_user(tsk->thread.ckpt_regs.ccr,
477 &sc->gp_regs[PT_CCR]);
479 /* These regs are not checkpointed; they can go in 'regs'. */
480 err |= __get_user(regs->trap, &sc->gp_regs[PT_TRAP]);
481 err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
482 err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
483 err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
486 * Force reload of FP/VEC.
487 * This has to be done before copying stuff into tsk->thread.fpr/vr
488 * for the reasons explained in the previous comment.
490 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
492 #ifdef CONFIG_ALTIVEC
493 err |= __get_user(v_regs, &sc->v_regs);
494 err |= __get_user(tm_v_regs, &tm_sc->v_regs);
497 if (v_regs && !access_ok(VERIFY_READ, v_regs, 34 * sizeof(vector128)))
499 if (tm_v_regs && !access_ok(VERIFY_READ,
500 tm_v_regs, 34 * sizeof(vector128)))
502 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
503 if (v_regs != NULL && tm_v_regs != NULL && (msr & MSR_VEC) != 0) {
504 err |= __copy_from_user(&tsk->thread.vr_state, v_regs,
505 33 * sizeof(vector128));
506 err |= __copy_from_user(&tsk->thread.transact_vr, tm_v_regs,
507 33 * sizeof(vector128));
508 current->thread.used_vr = true;
510 else if (tsk->thread.used_vr) {
511 memset(&tsk->thread.vr_state, 0, 33 * sizeof(vector128));
512 memset(&tsk->thread.transact_vr, 0, 33 * sizeof(vector128));
514 /* Always get VRSAVE back */
515 if (v_regs != NULL && tm_v_regs != NULL) {
516 err |= __get_user(tsk->thread.vrsave,
517 (u32 __user *)&v_regs[33]);
518 err |= __get_user(tsk->thread.transact_vrsave,
519 (u32 __user *)&tm_v_regs[33]);
522 tsk->thread.vrsave = 0;
523 tsk->thread.transact_vrsave = 0;
525 if (cpu_has_feature(CPU_FTR_ALTIVEC))
526 mtspr(SPRN_VRSAVE, tsk->thread.vrsave);
527 #endif /* CONFIG_ALTIVEC */
528 /* restore floating point */
529 err |= copy_fpr_from_user(tsk, &sc->fp_regs);
530 err |= copy_transact_fpr_from_user(tsk, &tm_sc->fp_regs);
533 * Get additional VSX data. Update v_regs to point after the
534 * VMX data. Copy VSX low doubleword from userspace to local
535 * buffer for formatting, then into the taskstruct.
537 if (v_regs && ((msr & MSR_VSX) != 0)) {
538 v_regs += ELF_NVRREG;
539 tm_v_regs += ELF_NVRREG;
540 err |= copy_vsx_from_user(tsk, v_regs);
541 err |= copy_transact_vsx_from_user(tsk, tm_v_regs);
542 tsk->thread.used_vsr = true;
544 for (i = 0; i < 32 ; i++) {
545 tsk->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
546 tsk->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET] = 0;
551 /* Make sure the transaction is marked as failed */
552 tsk->thread.tm_texasr |= TEXASR_FS;
553 /* This loads the checkpointed FP/VEC state, if used */
554 tm_recheckpoint(&tsk->thread, msr);
556 /* This loads the speculative FP/VEC state, if used */
558 do_load_up_transact_fpu(&tsk->thread);
559 regs->msr |= (MSR_FP | tsk->thread.fpexc_mode);
561 #ifdef CONFIG_ALTIVEC
563 do_load_up_transact_altivec(&tsk->thread);
564 regs->msr |= MSR_VEC;
573 * Setup the trampoline code on the stack
575 static long setup_trampoline(unsigned int syscall, unsigned int __user *tramp)
580 /* addi r1, r1, __SIGNAL_FRAMESIZE # Pop the dummy stackframe */
581 err |= __put_user(0x38210000UL | (__SIGNAL_FRAMESIZE & 0xffff), &tramp[0]);
582 /* li r0, __NR_[rt_]sigreturn| */
583 err |= __put_user(0x38000000UL | (syscall & 0xffff), &tramp[1]);
585 err |= __put_user(0x44000002UL, &tramp[2]);
587 /* Minimal traceback info */
588 for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)
589 err |= __put_user(0, &tramp[i]);
592 flush_icache_range((unsigned long) &tramp[0],
593 (unsigned long) &tramp[TRAMP_SIZE]);
599 * Userspace code may pass a ucontext which doesn't include VSX added
600 * at the end. We need to check for this case.
602 #define UCONTEXTSIZEWITHOUTVSX \
603 (sizeof(struct ucontext) - 32*sizeof(long))
606 * Handle {get,set,swap}_context operations
608 int sys_swapcontext(struct ucontext __user *old_ctx,
609 struct ucontext __user *new_ctx,
610 long ctx_size, long r6, long r7, long r8, struct pt_regs *regs)
614 unsigned long new_msr = 0;
615 int ctx_has_vsx_region = 0;
617 BUG_ON(regs != current->thread.regs);
620 get_user(new_msr, &new_ctx->uc_mcontext.gp_regs[PT_MSR]))
623 * Check that the context is not smaller than the original
624 * size (with VMX but without VSX)
626 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
629 * If the new context state sets the MSR VSX bits but
630 * it doesn't provide VSX state.
632 if ((ctx_size < sizeof(struct ucontext)) &&
635 /* Does the context have enough room to store VSX data? */
636 if (ctx_size >= sizeof(struct ucontext))
637 ctx_has_vsx_region = 1;
639 if (old_ctx != NULL) {
640 if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size)
641 || setup_sigcontext(&old_ctx->uc_mcontext, current, 0, NULL, 0,
643 || __copy_to_user(&old_ctx->uc_sigmask,
644 ¤t->blocked, sizeof(sigset_t)))
649 if (!access_ok(VERIFY_READ, new_ctx, ctx_size)
650 || __get_user(tmp, (u8 __user *) new_ctx)
651 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
655 * If we get a fault copying the context into the kernel's
656 * image of the user's registers, we can't just return -EFAULT
657 * because the user's registers will be corrupted. For instance
658 * the NIP value may have been updated but not some of the
659 * other registers. Given that we have done the access_ok
660 * and successfully read the first and last bytes of the region
661 * above, this should only happen in an out-of-memory situation
662 * or if another thread unmaps the region containing the context.
663 * We kill the task with a SIGSEGV in this situation.
666 if (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
668 set_current_blocked(&set);
669 if (restore_sigcontext(current, NULL, 0, &new_ctx->uc_mcontext))
672 /* This returns like rt_sigreturn */
673 set_thread_flag(TIF_RESTOREALL);
679 * Do a signal return; undo the signal stack.
682 int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
683 unsigned long r6, unsigned long r7, unsigned long r8,
684 struct pt_regs *regs)
686 struct ucontext __user *uc = (struct ucontext __user *)regs->gpr[1];
688 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
692 BUG_ON(current->thread.regs != regs);
694 /* Always make any pending restarted system calls return -EINTR */
695 current->restart_block.fn = do_no_restart_syscall;
697 if (!access_ok(VERIFY_READ, uc, sizeof(*uc)))
700 if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
702 set_current_blocked(&set);
704 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
706 * If there is a transactional state then throw it away.
707 * The purpose of a sigreturn is to destroy all traces of the
708 * signal frame, this includes any transactional state created
709 * within in. We only check for suspended as we can never be
710 * active in the kernel, we are active, there is nothing better to
711 * do than go ahead and Bad Thing later.
712 * The cause is not important as there will never be a
713 * recheckpoint so it's not user visible.
715 if (MSR_TM_SUSPENDED(mfmsr()))
716 tm_reclaim_current(0);
718 if (__get_user(msr, &uc->uc_mcontext.gp_regs[PT_MSR]))
720 if (MSR_TM_ACTIVE(msr)) {
721 /* We recheckpoint on return. */
722 struct ucontext __user *uc_transact;
723 if (__get_user(uc_transact, &uc->uc_link))
725 if (restore_tm_sigcontexts(current, &uc->uc_mcontext,
726 &uc_transact->uc_mcontext))
730 /* Fall through, for non-TM restore */
732 if (restore_sigcontext(current, NULL, 1, &uc->uc_mcontext))
735 if (restore_altstack(&uc->uc_stack))
738 set_thread_flag(TIF_RESTOREALL);
742 if (show_unhandled_signals)
743 printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
744 current->comm, current->pid, "rt_sigreturn",
745 (long)uc, regs->nip, regs->link);
747 force_sig(SIGSEGV, current);
751 int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
752 struct task_struct *tsk)
754 struct rt_sigframe __user *frame;
755 unsigned long newsp = 0;
757 struct pt_regs *regs = tsk->thread.regs;
759 BUG_ON(tsk != current);
761 frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 0);
762 if (unlikely(frame == NULL))
765 err |= __put_user(&frame->info, &frame->pinfo);
766 err |= __put_user(&frame->uc, &frame->puc);
767 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
771 /* Create the ucontext. */
772 err |= __put_user(0, &frame->uc.uc_flags);
773 err |= __save_altstack(&frame->uc.uc_stack, regs->gpr[1]);
774 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
775 if (MSR_TM_ACTIVE(regs->msr)) {
776 /* The ucontext_t passed to userland points to the second
777 * ucontext_t (for transactional state) with its uc_link ptr.
779 err |= __put_user(&frame->uc_transact, &frame->uc.uc_link);
780 err |= setup_tm_sigcontexts(&frame->uc.uc_mcontext,
781 &frame->uc_transact.uc_mcontext,
782 tsk, ksig->sig, NULL,
783 (unsigned long)ksig->ka.sa.sa_handler);
787 err |= __put_user(0, &frame->uc.uc_link);
788 err |= setup_sigcontext(&frame->uc.uc_mcontext, tsk, ksig->sig,
789 NULL, (unsigned long)ksig->ka.sa.sa_handler,
792 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
796 /* Make sure signal handler doesn't get spurious FP exceptions */
797 tsk->thread.fp_state.fpscr = 0;
799 /* Set up to return from userspace. */
800 if (vdso64_rt_sigtramp && tsk->mm->context.vdso_base) {
801 regs->link = tsk->mm->context.vdso_base + vdso64_rt_sigtramp;
803 err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
806 regs->link = (unsigned long) &frame->tramp[0];
809 /* Allocate a dummy caller frame for the signal handler. */
810 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
811 err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
813 /* Set up "regs" so we "return" to the signal handler. */
814 if (is_elf2_task()) {
815 regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
816 regs->gpr[12] = regs->nip;
818 /* Handler is *really* a pointer to the function descriptor for
819 * the signal routine. The first entry in the function
820 * descriptor is the entry address of signal and the second
821 * entry is the TOC value we need to use.
823 func_descr_t __user *funct_desc_ptr =
824 (func_descr_t __user *) ksig->ka.sa.sa_handler;
826 err |= get_user(regs->nip, &funct_desc_ptr->entry);
827 err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
830 /* enter the signal handler in native-endian mode */
831 regs->msr &= ~MSR_LE;
832 regs->msr |= (MSR_KERNEL & MSR_LE);
833 regs->gpr[1] = newsp;
834 regs->gpr[3] = ksig->sig;
836 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
837 err |= get_user(regs->gpr[4], (unsigned long __user *)&frame->pinfo);
838 err |= get_user(regs->gpr[5], (unsigned long __user *)&frame->puc);
839 regs->gpr[6] = (unsigned long) frame;
841 regs->gpr[4] = (unsigned long)&frame->uc.uc_mcontext;
849 if (show_unhandled_signals)
850 printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
851 tsk->comm, tsk->pid, "setup_rt_frame",
852 (long)frame, regs->nip, regs->link);