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>
27 #include <linux/syscalls.h>
29 #include <asm/sigcontext.h>
30 #include <asm/ucontext.h>
31 #include <linux/uaccess.h>
32 #include <asm/pgtable.h>
33 #include <asm/unistd.h>
34 #include <asm/cacheflush.h>
35 #include <asm/syscalls.h>
37 #include <asm/switch_to.h>
39 #include <asm/asm-prototypes.h>
44 #define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
45 #define FP_REGS_SIZE sizeof(elf_fpregset_t)
47 #define TRAMP_TRACEBACK 3
51 * When we have signals to deliver, we set up on the user stack,
52 * going down from the original stack pointer:
53 * 1) a rt_sigframe struct which contains the ucontext
54 * 2) a gap of __SIGNAL_FRAMESIZE bytes which acts as a dummy caller
55 * frame for the signal handler.
59 /* sys_rt_sigreturn requires the ucontext be the first field */
61 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
62 struct ucontext uc_transact;
64 unsigned long _unused[2];
65 unsigned int tramp[TRAMP_SIZE];
66 struct siginfo __user *pinfo;
69 /* New 64 bit little-endian ABI allows redzone of 512 bytes below sp */
70 char abigap[USER_REDZONE_SIZE];
71 } __attribute__ ((aligned (16)));
73 static const char fmt32[] = KERN_INFO \
74 "%s[%d]: bad frame in %s: %08lx nip %08lx lr %08lx\n";
75 static const char fmt64[] = KERN_INFO \
76 "%s[%d]: bad frame in %s: %016lx nip %016lx lr %016lx\n";
79 * This computes a quad word aligned pointer inside the vmx_reserve array
80 * element. For historical reasons sigcontext might not be quad word aligned,
81 * but the location we write the VMX regs to must be. See the comment in
82 * sigcontext for more detail.
85 static elf_vrreg_t __user *sigcontext_vmx_regs(struct sigcontext __user *sc)
87 return (elf_vrreg_t __user *) (((unsigned long)sc->vmx_reserve + 15) & ~0xful);
92 * Set up the sigcontext for the signal frame.
95 static long setup_sigcontext(struct sigcontext __user *sc,
96 struct task_struct *tsk, int signr, sigset_t *set,
97 unsigned long handler, int ctx_has_vsx_region)
99 /* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
100 * process never used altivec yet (MSR_VEC is zero in pt_regs of
101 * the context). This is very important because we must ensure we
102 * don't lose the VRSAVE content that may have been set prior to
103 * the process doing its first vector operation
104 * Userland shall check AT_HWCAP to know whether it can rely on the
105 * v_regs pointer or not
107 #ifdef CONFIG_ALTIVEC
108 elf_vrreg_t __user *v_regs = sigcontext_vmx_regs(sc);
109 unsigned long vrsave;
111 struct pt_regs *regs = tsk->thread.regs;
112 unsigned long msr = regs->msr;
114 /* Force usr to alway see softe as 1 (interrupts enabled) */
115 unsigned long softe = 0x1;
117 BUG_ON(tsk != current);
119 #ifdef CONFIG_ALTIVEC
120 err |= __put_user(v_regs, &sc->v_regs);
122 /* save altivec registers */
123 if (tsk->thread.used_vr) {
124 flush_altivec_to_thread(tsk);
125 /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
126 err |= __copy_to_user(v_regs, &tsk->thread.vr_state,
127 33 * sizeof(vector128));
128 /* set MSR_VEC in the MSR value in the frame to indicate that sc->v_reg)
129 * contains valid data.
133 /* We always copy to/from vrsave, it's 0 if we don't have or don't
137 if (cpu_has_feature(CPU_FTR_ALTIVEC)) {
138 vrsave = mfspr(SPRN_VRSAVE);
139 tsk->thread.vrsave = vrsave;
142 err |= __put_user(vrsave, (u32 __user *)&v_regs[33]);
143 #else /* CONFIG_ALTIVEC */
144 err |= __put_user(0, &sc->v_regs);
145 #endif /* CONFIG_ALTIVEC */
146 flush_fp_to_thread(tsk);
147 /* copy fpr regs and fpscr */
148 err |= copy_fpr_to_user(&sc->fp_regs, tsk);
151 * Clear the MSR VSX bit to indicate there is no valid state attached
152 * to this context, except in the specific case below where we set it.
157 * Copy VSX low doubleword to local buffer for formatting,
158 * then out to userspace. Update v_regs to point after the
161 if (tsk->thread.used_vsr && ctx_has_vsx_region) {
162 flush_vsx_to_thread(tsk);
163 v_regs += ELF_NVRREG;
164 err |= copy_vsx_to_user(v_regs, tsk);
165 /* set MSR_VSX in the MSR value in the frame to
166 * indicate that sc->vs_reg) contains valid data.
170 #endif /* CONFIG_VSX */
171 err |= __put_user(&sc->gp_regs, &sc->regs);
172 WARN_ON(!FULL_REGS(regs));
173 err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE);
174 err |= __put_user(msr, &sc->gp_regs[PT_MSR]);
175 err |= __put_user(softe, &sc->gp_regs[PT_SOFTE]);
176 err |= __put_user(signr, &sc->signal);
177 err |= __put_user(handler, &sc->handler);
179 err |= __put_user(set->sig[0], &sc->oldmask);
184 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
186 * As above, but Transactional Memory is in use, so deliver sigcontexts
187 * containing checkpointed and transactional register states.
189 * To do this, we treclaim (done before entering here) to gather both sets of
190 * registers and set up the 'normal' sigcontext registers with rolled-back
191 * register values such that a simple signal handler sees a correct
192 * checkpointed register state. If interested, a TM-aware sighandler can
193 * examine the transactional registers in the 2nd sigcontext to determine the
194 * real origin of the signal.
196 static long setup_tm_sigcontexts(struct sigcontext __user *sc,
197 struct sigcontext __user *tm_sc,
198 struct task_struct *tsk,
199 int signr, sigset_t *set, unsigned long handler,
202 /* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
203 * process never used altivec yet (MSR_VEC is zero in pt_regs of
204 * the context). This is very important because we must ensure we
205 * don't lose the VRSAVE content that may have been set prior to
206 * the process doing its first vector operation
207 * Userland shall check AT_HWCAP to know wether it can rely on the
208 * v_regs pointer or not.
210 #ifdef CONFIG_ALTIVEC
211 elf_vrreg_t __user *v_regs = sigcontext_vmx_regs(sc);
212 elf_vrreg_t __user *tm_v_regs = sigcontext_vmx_regs(tm_sc);
214 struct pt_regs *regs = tsk->thread.regs;
217 BUG_ON(tsk != current);
219 BUG_ON(!MSR_TM_ACTIVE(msr));
221 WARN_ON(tm_suspend_disabled);
223 /* Restore checkpointed FP, VEC, and VSX bits from ckpt_regs as
224 * it contains the correct FP, VEC, VSX state after we treclaimed
225 * the transaction and giveup_all() was called on reclaiming.
227 msr |= tsk->thread.ckpt_regs.msr & (MSR_FP | MSR_VEC | MSR_VSX);
229 #ifdef CONFIG_ALTIVEC
230 err |= __put_user(v_regs, &sc->v_regs);
231 err |= __put_user(tm_v_regs, &tm_sc->v_regs);
233 /* save altivec registers */
234 if (tsk->thread.used_vr) {
235 /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
236 err |= __copy_to_user(v_regs, &tsk->thread.ckvr_state,
237 33 * sizeof(vector128));
238 /* If VEC was enabled there are transactional VRs valid too,
239 * else they're a copy of the checkpointed VRs.
242 err |= __copy_to_user(tm_v_regs,
243 &tsk->thread.vr_state,
244 33 * sizeof(vector128));
246 err |= __copy_to_user(tm_v_regs,
247 &tsk->thread.ckvr_state,
248 33 * sizeof(vector128));
250 /* set MSR_VEC in the MSR value in the frame to indicate
251 * that sc->v_reg contains valid data.
255 /* We always copy to/from vrsave, it's 0 if we don't have or don't
258 if (cpu_has_feature(CPU_FTR_ALTIVEC))
259 tsk->thread.ckvrsave = mfspr(SPRN_VRSAVE);
260 err |= __put_user(tsk->thread.ckvrsave, (u32 __user *)&v_regs[33]);
262 err |= __put_user(tsk->thread.vrsave,
263 (u32 __user *)&tm_v_regs[33]);
265 err |= __put_user(tsk->thread.ckvrsave,
266 (u32 __user *)&tm_v_regs[33]);
268 #else /* CONFIG_ALTIVEC */
269 err |= __put_user(0, &sc->v_regs);
270 err |= __put_user(0, &tm_sc->v_regs);
271 #endif /* CONFIG_ALTIVEC */
273 /* copy fpr regs and fpscr */
274 err |= copy_ckfpr_to_user(&sc->fp_regs, tsk);
276 err |= copy_fpr_to_user(&tm_sc->fp_regs, tsk);
278 err |= copy_ckfpr_to_user(&tm_sc->fp_regs, tsk);
282 * Copy VSX low doubleword to local buffer for formatting,
283 * then out to userspace. Update v_regs to point after the
286 if (tsk->thread.used_vsr) {
287 v_regs += ELF_NVRREG;
288 tm_v_regs += ELF_NVRREG;
290 err |= copy_ckvsx_to_user(v_regs, tsk);
293 err |= copy_vsx_to_user(tm_v_regs, tsk);
295 err |= copy_ckvsx_to_user(tm_v_regs, tsk);
297 /* set MSR_VSX in the MSR value in the frame to
298 * indicate that sc->vs_reg) contains valid data.
302 #endif /* CONFIG_VSX */
304 err |= __put_user(&sc->gp_regs, &sc->regs);
305 err |= __put_user(&tm_sc->gp_regs, &tm_sc->regs);
306 WARN_ON(!FULL_REGS(regs));
307 err |= __copy_to_user(&tm_sc->gp_regs, regs, GP_REGS_SIZE);
308 err |= __copy_to_user(&sc->gp_regs,
309 &tsk->thread.ckpt_regs, GP_REGS_SIZE);
310 err |= __put_user(msr, &tm_sc->gp_regs[PT_MSR]);
311 err |= __put_user(msr, &sc->gp_regs[PT_MSR]);
312 err |= __put_user(signr, &sc->signal);
313 err |= __put_user(handler, &sc->handler);
315 err |= __put_user(set->sig[0], &sc->oldmask);
322 * Restore the sigcontext from the signal frame.
325 static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
326 struct sigcontext __user *sc)
328 #ifdef CONFIG_ALTIVEC
329 elf_vrreg_t __user *v_regs;
331 unsigned long err = 0;
332 unsigned long save_r13 = 0;
334 struct pt_regs *regs = tsk->thread.regs;
339 BUG_ON(tsk != current);
341 /* If this is not a signal return, we preserve the TLS in r13 */
343 save_r13 = regs->gpr[13];
346 err |= __copy_from_user(regs->gpr, sc->gp_regs, sizeof(regs->gpr));
347 err |= __get_user(regs->nip, &sc->gp_regs[PT_NIP]);
348 /* get MSR separately, transfer the LE bit if doing signal return */
349 err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
351 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
352 err |= __get_user(regs->orig_gpr3, &sc->gp_regs[PT_ORIG_R3]);
353 err |= __get_user(regs->ctr, &sc->gp_regs[PT_CTR]);
354 err |= __get_user(regs->link, &sc->gp_regs[PT_LNK]);
355 err |= __get_user(regs->xer, &sc->gp_regs[PT_XER]);
356 err |= __get_user(regs->ccr, &sc->gp_regs[PT_CCR]);
359 err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
360 err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
361 err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
364 regs->gpr[13] = save_r13;
366 err |= __get_user(set->sig[0], &sc->oldmask);
369 * Force reload of FP/VEC.
370 * This has to be done before copying stuff into tsk->thread.fpr/vr
371 * for the reasons explained in the previous comment.
373 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
375 #ifdef CONFIG_ALTIVEC
376 err |= __get_user(v_regs, &sc->v_regs);
379 if (v_regs && !access_ok(VERIFY_READ, v_regs, 34 * sizeof(vector128)))
381 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
382 if (v_regs != NULL && (msr & MSR_VEC) != 0) {
383 err |= __copy_from_user(&tsk->thread.vr_state, v_regs,
384 33 * sizeof(vector128));
385 tsk->thread.used_vr = true;
386 } else if (tsk->thread.used_vr) {
387 memset(&tsk->thread.vr_state, 0, 33 * sizeof(vector128));
389 /* Always get VRSAVE back */
391 err |= __get_user(tsk->thread.vrsave, (u32 __user *)&v_regs[33]);
393 tsk->thread.vrsave = 0;
394 if (cpu_has_feature(CPU_FTR_ALTIVEC))
395 mtspr(SPRN_VRSAVE, tsk->thread.vrsave);
396 #endif /* CONFIG_ALTIVEC */
397 /* restore floating point */
398 err |= copy_fpr_from_user(tsk, &sc->fp_regs);
401 * Get additional VSX data. Update v_regs to point after the
402 * VMX data. Copy VSX low doubleword from userspace to local
403 * buffer for formatting, then into the taskstruct.
405 v_regs += ELF_NVRREG;
406 if ((msr & MSR_VSX) != 0) {
407 err |= copy_vsx_from_user(tsk, v_regs);
408 tsk->thread.used_vsr = true;
410 for (i = 0; i < 32 ; i++)
411 tsk->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
417 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
419 * Restore the two sigcontexts from the frame of a transactional processes.
422 static long restore_tm_sigcontexts(struct task_struct *tsk,
423 struct sigcontext __user *sc,
424 struct sigcontext __user *tm_sc)
426 #ifdef CONFIG_ALTIVEC
427 elf_vrreg_t __user *v_regs, *tm_v_regs;
429 unsigned long err = 0;
431 struct pt_regs *regs = tsk->thread.regs;
436 BUG_ON(tsk != current);
438 if (tm_suspend_disabled)
442 err |= __copy_from_user(regs->gpr, tm_sc->gp_regs, sizeof(regs->gpr));
443 err |= __copy_from_user(&tsk->thread.ckpt_regs, sc->gp_regs,
447 * TFHAR is restored from the checkpointed 'wound-back' ucontext's NIP.
448 * TEXASR was set by the signal delivery reclaim, as was TFIAR.
449 * Users doing anything abhorrent like thread-switching w/ signals for
450 * TM-Suspended code will have to back TEXASR/TFIAR up themselves.
451 * For the case of getting a signal and simply returning from it,
452 * we don't need to re-copy them here.
454 err |= __get_user(regs->nip, &tm_sc->gp_regs[PT_NIP]);
455 err |= __get_user(tsk->thread.tm_tfhar, &sc->gp_regs[PT_NIP]);
457 /* get MSR separately, transfer the LE bit if doing signal return */
458 err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
459 /* Don't allow reserved mode. */
460 if (MSR_TM_RESV(msr))
463 /* pull in MSR LE from user context */
464 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
466 /* The following non-GPR non-FPR non-VR state is also checkpointed: */
467 err |= __get_user(regs->ctr, &tm_sc->gp_regs[PT_CTR]);
468 err |= __get_user(regs->link, &tm_sc->gp_regs[PT_LNK]);
469 err |= __get_user(regs->xer, &tm_sc->gp_regs[PT_XER]);
470 err |= __get_user(regs->ccr, &tm_sc->gp_regs[PT_CCR]);
471 err |= __get_user(tsk->thread.ckpt_regs.ctr,
472 &sc->gp_regs[PT_CTR]);
473 err |= __get_user(tsk->thread.ckpt_regs.link,
474 &sc->gp_regs[PT_LNK]);
475 err |= __get_user(tsk->thread.ckpt_regs.xer,
476 &sc->gp_regs[PT_XER]);
477 err |= __get_user(tsk->thread.ckpt_regs.ccr,
478 &sc->gp_regs[PT_CCR]);
480 /* Don't allow userspace to set the trap value */
483 /* These regs are not checkpointed; they can go in 'regs'. */
484 err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
485 err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
486 err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
489 * Force reload of FP/VEC.
490 * This has to be done before copying stuff into tsk->thread.fpr/vr
491 * for the reasons explained in the previous comment.
493 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
495 #ifdef CONFIG_ALTIVEC
496 err |= __get_user(v_regs, &sc->v_regs);
497 err |= __get_user(tm_v_regs, &tm_sc->v_regs);
500 if (v_regs && !access_ok(VERIFY_READ, v_regs, 34 * sizeof(vector128)))
502 if (tm_v_regs && !access_ok(VERIFY_READ,
503 tm_v_regs, 34 * sizeof(vector128)))
505 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
506 if (v_regs != NULL && tm_v_regs != NULL && (msr & MSR_VEC) != 0) {
507 err |= __copy_from_user(&tsk->thread.ckvr_state, v_regs,
508 33 * sizeof(vector128));
509 err |= __copy_from_user(&tsk->thread.vr_state, tm_v_regs,
510 33 * sizeof(vector128));
511 current->thread.used_vr = true;
513 else if (tsk->thread.used_vr) {
514 memset(&tsk->thread.vr_state, 0, 33 * sizeof(vector128));
515 memset(&tsk->thread.ckvr_state, 0, 33 * sizeof(vector128));
517 /* Always get VRSAVE back */
518 if (v_regs != NULL && tm_v_regs != NULL) {
519 err |= __get_user(tsk->thread.ckvrsave,
520 (u32 __user *)&v_regs[33]);
521 err |= __get_user(tsk->thread.vrsave,
522 (u32 __user *)&tm_v_regs[33]);
525 tsk->thread.vrsave = 0;
526 tsk->thread.ckvrsave = 0;
528 if (cpu_has_feature(CPU_FTR_ALTIVEC))
529 mtspr(SPRN_VRSAVE, tsk->thread.vrsave);
530 #endif /* CONFIG_ALTIVEC */
531 /* restore floating point */
532 err |= copy_fpr_from_user(tsk, &tm_sc->fp_regs);
533 err |= copy_ckfpr_from_user(tsk, &sc->fp_regs);
536 * Get additional VSX data. Update v_regs to point after the
537 * VMX data. Copy VSX low doubleword from userspace to local
538 * buffer for formatting, then into the taskstruct.
540 if (v_regs && ((msr & MSR_VSX) != 0)) {
541 v_regs += ELF_NVRREG;
542 tm_v_regs += ELF_NVRREG;
543 err |= copy_vsx_from_user(tsk, tm_v_regs);
544 err |= copy_ckvsx_from_user(tsk, v_regs);
545 tsk->thread.used_vsr = true;
547 for (i = 0; i < 32 ; i++) {
548 tsk->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
549 tsk->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
554 /* Make sure the transaction is marked as failed */
555 tsk->thread.tm_texasr |= TEXASR_FS;
558 * Disabling preemption, since it is unsafe to be preempted
559 * with MSR[TS] set without recheckpointing.
563 /* pull in MSR TS bits from user context */
564 regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr & MSR_TS_MASK);
567 * Ensure that TM is enabled in regs->msr before we leave the signal
568 * handler. It could be the case that (a) user disabled the TM bit
569 * through the manipulation of the MSR bits in uc_mcontext or (b) the
570 * TM bit was disabled because a sufficient number of context switches
571 * happened whilst in the signal handler and load_tm overflowed,
572 * disabling the TM bit. In either case we can end up with an illegal
573 * TM state leading to a TM Bad Thing when we return to userspace.
576 * After regs->MSR[TS] being updated, make sure that get_user(),
577 * put_user() or similar functions are *not* called. These
578 * functions can generate page faults which will cause the process
579 * to be de-scheduled with MSR[TS] set but without calling
580 * tm_recheckpoint(). This can cause a bug.
584 /* This loads the checkpointed FP/VEC state, if used */
585 tm_recheckpoint(&tsk->thread);
587 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
589 load_fp_state(&tsk->thread.fp_state);
590 regs->msr |= (MSR_FP | tsk->thread.fpexc_mode);
593 load_vr_state(&tsk->thread.vr_state);
594 regs->msr |= MSR_VEC;
604 * Setup the trampoline code on the stack
606 static long setup_trampoline(unsigned int syscall, unsigned int __user *tramp)
611 /* addi r1, r1, __SIGNAL_FRAMESIZE # Pop the dummy stackframe */
612 err |= __put_user(0x38210000UL | (__SIGNAL_FRAMESIZE & 0xffff), &tramp[0]);
613 /* li r0, __NR_[rt_]sigreturn| */
614 err |= __put_user(0x38000000UL | (syscall & 0xffff), &tramp[1]);
616 err |= __put_user(0x44000002UL, &tramp[2]);
618 /* Minimal traceback info */
619 for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)
620 err |= __put_user(0, &tramp[i]);
623 flush_icache_range((unsigned long) &tramp[0],
624 (unsigned long) &tramp[TRAMP_SIZE]);
630 * Userspace code may pass a ucontext which doesn't include VSX added
631 * at the end. We need to check for this case.
633 #define UCONTEXTSIZEWITHOUTVSX \
634 (sizeof(struct ucontext) - 32*sizeof(long))
637 * Handle {get,set,swap}_context operations
639 SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
640 struct ucontext __user *, new_ctx, long, ctx_size)
644 unsigned long new_msr = 0;
645 int ctx_has_vsx_region = 0;
648 get_user(new_msr, &new_ctx->uc_mcontext.gp_regs[PT_MSR]))
651 * Check that the context is not smaller than the original
652 * size (with VMX but without VSX)
654 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
657 * If the new context state sets the MSR VSX bits but
658 * it doesn't provide VSX state.
660 if ((ctx_size < sizeof(struct ucontext)) &&
663 /* Does the context have enough room to store VSX data? */
664 if (ctx_size >= sizeof(struct ucontext))
665 ctx_has_vsx_region = 1;
667 if (old_ctx != NULL) {
668 if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size)
669 || setup_sigcontext(&old_ctx->uc_mcontext, current, 0, NULL, 0,
671 || __copy_to_user(&old_ctx->uc_sigmask,
672 ¤t->blocked, sizeof(sigset_t)))
677 if (!access_ok(VERIFY_READ, new_ctx, ctx_size)
678 || __get_user(tmp, (u8 __user *) new_ctx)
679 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
683 * If we get a fault copying the context into the kernel's
684 * image of the user's registers, we can't just return -EFAULT
685 * because the user's registers will be corrupted. For instance
686 * the NIP value may have been updated but not some of the
687 * other registers. Given that we have done the access_ok
688 * and successfully read the first and last bytes of the region
689 * above, this should only happen in an out-of-memory situation
690 * or if another thread unmaps the region containing the context.
691 * We kill the task with a SIGSEGV in this situation.
694 if (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
696 set_current_blocked(&set);
697 if (restore_sigcontext(current, NULL, 0, &new_ctx->uc_mcontext))
700 /* This returns like rt_sigreturn */
701 set_thread_flag(TIF_RESTOREALL);
707 * Do a signal return; undo the signal stack.
710 SYSCALL_DEFINE0(rt_sigreturn)
712 struct pt_regs *regs = current_pt_regs();
713 struct ucontext __user *uc = (struct ucontext __user *)regs->gpr[1];
715 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
719 /* Always make any pending restarted system calls return -EINTR */
720 current->restart_block.fn = do_no_restart_syscall;
722 if (!access_ok(VERIFY_READ, uc, sizeof(*uc)))
725 if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
727 set_current_blocked(&set);
729 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
731 * If there is a transactional state then throw it away.
732 * The purpose of a sigreturn is to destroy all traces of the
733 * signal frame, this includes any transactional state created
734 * within in. We only check for suspended as we can never be
735 * active in the kernel, we are active, there is nothing better to
736 * do than go ahead and Bad Thing later.
737 * The cause is not important as there will never be a
738 * recheckpoint so it's not user visible.
740 if (MSR_TM_SUSPENDED(mfmsr()))
741 tm_reclaim_current(0);
743 if (__get_user(msr, &uc->uc_mcontext.gp_regs[PT_MSR]))
745 if (MSR_TM_ACTIVE(msr)) {
746 /* We recheckpoint on return. */
747 struct ucontext __user *uc_transact;
749 /* Trying to start TM on non TM system */
750 if (!cpu_has_feature(CPU_FTR_TM))
753 if (__get_user(uc_transact, &uc->uc_link))
755 if (restore_tm_sigcontexts(current, &uc->uc_mcontext,
756 &uc_transact->uc_mcontext))
762 * Fall through, for non-TM restore
764 * Unset MSR[TS] on the thread regs since MSR from user
765 * context does not have MSR active, and recheckpoint was
766 * not called since restore_tm_sigcontexts() was not called
769 * If not unsetting it, the code can RFID to userspace with
770 * MSR[TS] set, but without CPU in the proper state,
771 * causing a TM bad thing.
773 current->thread.regs->msr &= ~MSR_TS_MASK;
774 if (restore_sigcontext(current, NULL, 1, &uc->uc_mcontext))
778 if (restore_altstack(&uc->uc_stack))
781 set_thread_flag(TIF_RESTOREALL);
785 if (show_unhandled_signals)
786 printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
787 current->comm, current->pid, "rt_sigreturn",
788 (long)uc, regs->nip, regs->link);
790 force_sig(SIGSEGV, current);
794 int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
795 struct task_struct *tsk)
797 struct rt_sigframe __user *frame;
798 unsigned long newsp = 0;
800 struct pt_regs *regs = tsk->thread.regs;
801 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
802 /* Save the thread's msr before get_tm_stackpointer() changes it */
803 unsigned long msr = regs->msr;
806 BUG_ON(tsk != current);
808 frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 0);
809 if (unlikely(frame == NULL))
812 err |= __put_user(&frame->info, &frame->pinfo);
813 err |= __put_user(&frame->uc, &frame->puc);
814 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
818 /* Create the ucontext. */
819 err |= __put_user(0, &frame->uc.uc_flags);
820 err |= __save_altstack(&frame->uc.uc_stack, regs->gpr[1]);
821 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
822 if (MSR_TM_ACTIVE(msr)) {
823 /* The ucontext_t passed to userland points to the second
824 * ucontext_t (for transactional state) with its uc_link ptr.
826 err |= __put_user(&frame->uc_transact, &frame->uc.uc_link);
827 err |= setup_tm_sigcontexts(&frame->uc.uc_mcontext,
828 &frame->uc_transact.uc_mcontext,
829 tsk, ksig->sig, NULL,
830 (unsigned long)ksig->ka.sa.sa_handler,
835 err |= __put_user(0, &frame->uc.uc_link);
836 err |= setup_sigcontext(&frame->uc.uc_mcontext, tsk, ksig->sig,
837 NULL, (unsigned long)ksig->ka.sa.sa_handler,
840 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
844 /* Make sure signal handler doesn't get spurious FP exceptions */
845 tsk->thread.fp_state.fpscr = 0;
847 /* Set up to return from userspace. */
848 if (vdso64_rt_sigtramp && tsk->mm->context.vdso_base) {
849 regs->link = tsk->mm->context.vdso_base + vdso64_rt_sigtramp;
851 err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
854 regs->link = (unsigned long) &frame->tramp[0];
857 /* Allocate a dummy caller frame for the signal handler. */
858 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
859 err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
861 /* Set up "regs" so we "return" to the signal handler. */
862 if (is_elf2_task()) {
863 regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
864 regs->gpr[12] = regs->nip;
866 /* Handler is *really* a pointer to the function descriptor for
867 * the signal routine. The first entry in the function
868 * descriptor is the entry address of signal and the second
869 * entry is the TOC value we need to use.
871 func_descr_t __user *funct_desc_ptr =
872 (func_descr_t __user *) ksig->ka.sa.sa_handler;
874 err |= get_user(regs->nip, &funct_desc_ptr->entry);
875 err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
878 /* enter the signal handler in native-endian mode */
879 regs->msr &= ~MSR_LE;
880 regs->msr |= (MSR_KERNEL & MSR_LE);
881 regs->gpr[1] = newsp;
882 regs->gpr[3] = ksig->sig;
884 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
885 err |= get_user(regs->gpr[4], (unsigned long __user *)&frame->pinfo);
886 err |= get_user(regs->gpr[5], (unsigned long __user *)&frame->puc);
887 regs->gpr[6] = (unsigned long) frame;
889 regs->gpr[4] = (unsigned long)&frame->uc.uc_mcontext;
897 if (show_unhandled_signals)
898 printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
899 tsk->comm, tsk->pid, "setup_rt_frame",
900 (long)frame, regs->nip, regs->link);