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)
201 /* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
202 * process never used altivec yet (MSR_VEC is zero in pt_regs of
203 * the context). This is very important because we must ensure we
204 * don't lose the VRSAVE content that may have been set prior to
205 * the process doing its first vector operation
206 * Userland shall check AT_HWCAP to know wether it can rely on the
207 * v_regs pointer or not.
209 #ifdef CONFIG_ALTIVEC
210 elf_vrreg_t __user *v_regs = sigcontext_vmx_regs(sc);
211 elf_vrreg_t __user *tm_v_regs = sigcontext_vmx_regs(tm_sc);
213 struct pt_regs *regs = tsk->thread.regs;
214 unsigned long msr = tsk->thread.regs->msr;
217 BUG_ON(tsk != current);
219 BUG_ON(!MSR_TM_ACTIVE(regs->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 /* Remove TM bits from thread's MSR. The MSR in the sigcontext
230 * just indicates to userland that we were doing a transaction, but we
231 * don't want to return in transactional state. This also ensures
232 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
234 regs->msr &= ~MSR_TS_MASK;
236 #ifdef CONFIG_ALTIVEC
237 err |= __put_user(v_regs, &sc->v_regs);
238 err |= __put_user(tm_v_regs, &tm_sc->v_regs);
240 /* save altivec registers */
241 if (tsk->thread.used_vr) {
242 /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
243 err |= __copy_to_user(v_regs, &tsk->thread.ckvr_state,
244 33 * sizeof(vector128));
245 /* If VEC was enabled there are transactional VRs valid too,
246 * else they're a copy of the checkpointed VRs.
249 err |= __copy_to_user(tm_v_regs,
250 &tsk->thread.vr_state,
251 33 * sizeof(vector128));
253 err |= __copy_to_user(tm_v_regs,
254 &tsk->thread.ckvr_state,
255 33 * sizeof(vector128));
257 /* set MSR_VEC in the MSR value in the frame to indicate
258 * that sc->v_reg contains valid data.
262 /* We always copy to/from vrsave, it's 0 if we don't have or don't
265 if (cpu_has_feature(CPU_FTR_ALTIVEC))
266 tsk->thread.ckvrsave = mfspr(SPRN_VRSAVE);
267 err |= __put_user(tsk->thread.ckvrsave, (u32 __user *)&v_regs[33]);
269 err |= __put_user(tsk->thread.vrsave,
270 (u32 __user *)&tm_v_regs[33]);
272 err |= __put_user(tsk->thread.ckvrsave,
273 (u32 __user *)&tm_v_regs[33]);
275 #else /* CONFIG_ALTIVEC */
276 err |= __put_user(0, &sc->v_regs);
277 err |= __put_user(0, &tm_sc->v_regs);
278 #endif /* CONFIG_ALTIVEC */
280 /* copy fpr regs and fpscr */
281 err |= copy_ckfpr_to_user(&sc->fp_regs, tsk);
283 err |= copy_fpr_to_user(&tm_sc->fp_regs, tsk);
285 err |= copy_ckfpr_to_user(&tm_sc->fp_regs, tsk);
289 * Copy VSX low doubleword to local buffer for formatting,
290 * then out to userspace. Update v_regs to point after the
293 if (tsk->thread.used_vsr) {
294 v_regs += ELF_NVRREG;
295 tm_v_regs += ELF_NVRREG;
297 err |= copy_ckvsx_to_user(v_regs, tsk);
300 err |= copy_vsx_to_user(tm_v_regs, tsk);
302 err |= copy_ckvsx_to_user(tm_v_regs, tsk);
304 /* set MSR_VSX in the MSR value in the frame to
305 * indicate that sc->vs_reg) contains valid data.
309 #endif /* CONFIG_VSX */
311 err |= __put_user(&sc->gp_regs, &sc->regs);
312 err |= __put_user(&tm_sc->gp_regs, &tm_sc->regs);
313 WARN_ON(!FULL_REGS(regs));
314 err |= __copy_to_user(&tm_sc->gp_regs, regs, GP_REGS_SIZE);
315 err |= __copy_to_user(&sc->gp_regs,
316 &tsk->thread.ckpt_regs, GP_REGS_SIZE);
317 err |= __put_user(msr, &tm_sc->gp_regs[PT_MSR]);
318 err |= __put_user(msr, &sc->gp_regs[PT_MSR]);
319 err |= __put_user(signr, &sc->signal);
320 err |= __put_user(handler, &sc->handler);
322 err |= __put_user(set->sig[0], &sc->oldmask);
329 * Restore the sigcontext from the signal frame.
332 static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
333 struct sigcontext __user *sc)
335 #ifdef CONFIG_ALTIVEC
336 elf_vrreg_t __user *v_regs;
338 unsigned long err = 0;
339 unsigned long save_r13 = 0;
341 struct pt_regs *regs = tsk->thread.regs;
346 BUG_ON(tsk != current);
348 /* If this is not a signal return, we preserve the TLS in r13 */
350 save_r13 = regs->gpr[13];
353 err |= __copy_from_user(regs->gpr, sc->gp_regs, sizeof(regs->gpr));
354 err |= __get_user(regs->nip, &sc->gp_regs[PT_NIP]);
355 /* get MSR separately, transfer the LE bit if doing signal return */
356 err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
358 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
359 err |= __get_user(regs->orig_gpr3, &sc->gp_regs[PT_ORIG_R3]);
360 err |= __get_user(regs->ctr, &sc->gp_regs[PT_CTR]);
361 err |= __get_user(regs->link, &sc->gp_regs[PT_LNK]);
362 err |= __get_user(regs->xer, &sc->gp_regs[PT_XER]);
363 err |= __get_user(regs->ccr, &sc->gp_regs[PT_CCR]);
366 err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
367 err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
368 err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
371 regs->gpr[13] = save_r13;
373 err |= __get_user(set->sig[0], &sc->oldmask);
376 * Force reload of FP/VEC.
377 * This has to be done before copying stuff into tsk->thread.fpr/vr
378 * for the reasons explained in the previous comment.
380 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
382 #ifdef CONFIG_ALTIVEC
383 err |= __get_user(v_regs, &sc->v_regs);
386 if (v_regs && !access_ok(v_regs, 34 * sizeof(vector128)))
388 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
389 if (v_regs != NULL && (msr & MSR_VEC) != 0) {
390 err |= __copy_from_user(&tsk->thread.vr_state, v_regs,
391 33 * sizeof(vector128));
392 tsk->thread.used_vr = true;
393 } else if (tsk->thread.used_vr) {
394 memset(&tsk->thread.vr_state, 0, 33 * sizeof(vector128));
396 /* Always get VRSAVE back */
398 err |= __get_user(tsk->thread.vrsave, (u32 __user *)&v_regs[33]);
400 tsk->thread.vrsave = 0;
401 if (cpu_has_feature(CPU_FTR_ALTIVEC))
402 mtspr(SPRN_VRSAVE, tsk->thread.vrsave);
403 #endif /* CONFIG_ALTIVEC */
404 /* restore floating point */
405 err |= copy_fpr_from_user(tsk, &sc->fp_regs);
408 * Get additional VSX data. Update v_regs to point after the
409 * VMX data. Copy VSX low doubleword from userspace to local
410 * buffer for formatting, then into the taskstruct.
412 v_regs += ELF_NVRREG;
413 if ((msr & MSR_VSX) != 0) {
414 err |= copy_vsx_from_user(tsk, v_regs);
415 tsk->thread.used_vsr = true;
417 for (i = 0; i < 32 ; i++)
418 tsk->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
424 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
426 * Restore the two sigcontexts from the frame of a transactional processes.
429 static long restore_tm_sigcontexts(struct task_struct *tsk,
430 struct sigcontext __user *sc,
431 struct sigcontext __user *tm_sc)
433 #ifdef CONFIG_ALTIVEC
434 elf_vrreg_t __user *v_regs, *tm_v_regs;
436 unsigned long err = 0;
438 struct pt_regs *regs = tsk->thread.regs;
443 BUG_ON(tsk != current);
445 if (tm_suspend_disabled)
449 err |= __copy_from_user(regs->gpr, tm_sc->gp_regs, sizeof(regs->gpr));
450 err |= __copy_from_user(&tsk->thread.ckpt_regs, sc->gp_regs,
454 * TFHAR is restored from the checkpointed 'wound-back' ucontext's NIP.
455 * TEXASR was set by the signal delivery reclaim, as was TFIAR.
456 * Users doing anything abhorrent like thread-switching w/ signals for
457 * TM-Suspended code will have to back TEXASR/TFIAR up themselves.
458 * For the case of getting a signal and simply returning from it,
459 * we don't need to re-copy them here.
461 err |= __get_user(regs->nip, &tm_sc->gp_regs[PT_NIP]);
462 err |= __get_user(tsk->thread.tm_tfhar, &sc->gp_regs[PT_NIP]);
464 /* get MSR separately, transfer the LE bit if doing signal return */
465 err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
466 /* Don't allow reserved mode. */
467 if (MSR_TM_RESV(msr))
470 /* pull in MSR LE from user context */
471 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
473 /* The following non-GPR non-FPR non-VR state is also checkpointed: */
474 err |= __get_user(regs->ctr, &tm_sc->gp_regs[PT_CTR]);
475 err |= __get_user(regs->link, &tm_sc->gp_regs[PT_LNK]);
476 err |= __get_user(regs->xer, &tm_sc->gp_regs[PT_XER]);
477 err |= __get_user(regs->ccr, &tm_sc->gp_regs[PT_CCR]);
478 err |= __get_user(tsk->thread.ckpt_regs.ctr,
479 &sc->gp_regs[PT_CTR]);
480 err |= __get_user(tsk->thread.ckpt_regs.link,
481 &sc->gp_regs[PT_LNK]);
482 err |= __get_user(tsk->thread.ckpt_regs.xer,
483 &sc->gp_regs[PT_XER]);
484 err |= __get_user(tsk->thread.ckpt_regs.ccr,
485 &sc->gp_regs[PT_CCR]);
487 /* These regs are not checkpointed; they can go in 'regs'. */
488 err |= __get_user(regs->trap, &sc->gp_regs[PT_TRAP]);
489 err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
490 err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
491 err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
494 * Force reload of FP/VEC.
495 * This has to be done before copying stuff into tsk->thread.fpr/vr
496 * for the reasons explained in the previous comment.
498 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
500 #ifdef CONFIG_ALTIVEC
501 err |= __get_user(v_regs, &sc->v_regs);
502 err |= __get_user(tm_v_regs, &tm_sc->v_regs);
505 if (v_regs && !access_ok(v_regs, 34 * sizeof(vector128)))
507 if (tm_v_regs && !access_ok(tm_v_regs, 34 * sizeof(vector128)))
509 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
510 if (v_regs != NULL && tm_v_regs != NULL && (msr & MSR_VEC) != 0) {
511 err |= __copy_from_user(&tsk->thread.ckvr_state, v_regs,
512 33 * sizeof(vector128));
513 err |= __copy_from_user(&tsk->thread.vr_state, tm_v_regs,
514 33 * sizeof(vector128));
515 current->thread.used_vr = true;
517 else if (tsk->thread.used_vr) {
518 memset(&tsk->thread.vr_state, 0, 33 * sizeof(vector128));
519 memset(&tsk->thread.ckvr_state, 0, 33 * sizeof(vector128));
521 /* Always get VRSAVE back */
522 if (v_regs != NULL && tm_v_regs != NULL) {
523 err |= __get_user(tsk->thread.ckvrsave,
524 (u32 __user *)&v_regs[33]);
525 err |= __get_user(tsk->thread.vrsave,
526 (u32 __user *)&tm_v_regs[33]);
529 tsk->thread.vrsave = 0;
530 tsk->thread.ckvrsave = 0;
532 if (cpu_has_feature(CPU_FTR_ALTIVEC))
533 mtspr(SPRN_VRSAVE, tsk->thread.vrsave);
534 #endif /* CONFIG_ALTIVEC */
535 /* restore floating point */
536 err |= copy_fpr_from_user(tsk, &tm_sc->fp_regs);
537 err |= copy_ckfpr_from_user(tsk, &sc->fp_regs);
540 * Get additional VSX data. Update v_regs to point after the
541 * VMX data. Copy VSX low doubleword from userspace to local
542 * buffer for formatting, then into the taskstruct.
544 if (v_regs && ((msr & MSR_VSX) != 0)) {
545 v_regs += ELF_NVRREG;
546 tm_v_regs += ELF_NVRREG;
547 err |= copy_vsx_from_user(tsk, tm_v_regs);
548 err |= copy_ckvsx_from_user(tsk, v_regs);
549 tsk->thread.used_vsr = true;
551 for (i = 0; i < 32 ; i++) {
552 tsk->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
553 tsk->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
558 /* Make sure the transaction is marked as failed */
559 tsk->thread.tm_texasr |= TEXASR_FS;
562 * Disabling preemption, since it is unsafe to be preempted
563 * with MSR[TS] set without recheckpointing.
567 /* pull in MSR TS bits from user context */
568 regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr & MSR_TS_MASK);
571 * Ensure that TM is enabled in regs->msr before we leave the signal
572 * handler. It could be the case that (a) user disabled the TM bit
573 * through the manipulation of the MSR bits in uc_mcontext or (b) the
574 * TM bit was disabled because a sufficient number of context switches
575 * happened whilst in the signal handler and load_tm overflowed,
576 * disabling the TM bit. In either case we can end up with an illegal
577 * TM state leading to a TM Bad Thing when we return to userspace.
580 * After regs->MSR[TS] being updated, make sure that get_user(),
581 * put_user() or similar functions are *not* called. These
582 * functions can generate page faults which will cause the process
583 * to be de-scheduled with MSR[TS] set but without calling
584 * tm_recheckpoint(). This can cause a bug.
588 /* This loads the checkpointed FP/VEC state, if used */
589 tm_recheckpoint(&tsk->thread);
591 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
593 load_fp_state(&tsk->thread.fp_state);
594 regs->msr |= (MSR_FP | tsk->thread.fpexc_mode);
597 load_vr_state(&tsk->thread.vr_state);
598 regs->msr |= MSR_VEC;
608 * Setup the trampoline code on the stack
610 static long setup_trampoline(unsigned int syscall, unsigned int __user *tramp)
615 /* addi r1, r1, __SIGNAL_FRAMESIZE # Pop the dummy stackframe */
616 err |= __put_user(PPC_INST_ADDI | __PPC_RT(R1) | __PPC_RA(R1) |
617 (__SIGNAL_FRAMESIZE & 0xffff), &tramp[0]);
618 /* li r0, __NR_[rt_]sigreturn| */
619 err |= __put_user(PPC_INST_ADDI | (syscall & 0xffff), &tramp[1]);
621 err |= __put_user(PPC_INST_SC, &tramp[2]);
623 /* Minimal traceback info */
624 for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)
625 err |= __put_user(0, &tramp[i]);
628 flush_icache_range((unsigned long) &tramp[0],
629 (unsigned long) &tramp[TRAMP_SIZE]);
635 * Userspace code may pass a ucontext which doesn't include VSX added
636 * at the end. We need to check for this case.
638 #define UCONTEXTSIZEWITHOUTVSX \
639 (sizeof(struct ucontext) - 32*sizeof(long))
642 * Handle {get,set,swap}_context operations
644 SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
645 struct ucontext __user *, new_ctx, long, ctx_size)
649 unsigned long new_msr = 0;
650 int ctx_has_vsx_region = 0;
653 get_user(new_msr, &new_ctx->uc_mcontext.gp_regs[PT_MSR]))
656 * Check that the context is not smaller than the original
657 * size (with VMX but without VSX)
659 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
662 * If the new context state sets the MSR VSX bits but
663 * it doesn't provide VSX state.
665 if ((ctx_size < sizeof(struct ucontext)) &&
668 /* Does the context have enough room to store VSX data? */
669 if (ctx_size >= sizeof(struct ucontext))
670 ctx_has_vsx_region = 1;
672 if (old_ctx != NULL) {
673 if (!access_ok(old_ctx, ctx_size)
674 || setup_sigcontext(&old_ctx->uc_mcontext, current, 0, NULL, 0,
676 || __copy_to_user(&old_ctx->uc_sigmask,
677 ¤t->blocked, sizeof(sigset_t)))
682 if (!access_ok(new_ctx, ctx_size)
683 || __get_user(tmp, (u8 __user *) new_ctx)
684 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
688 * If we get a fault copying the context into the kernel's
689 * image of the user's registers, we can't just return -EFAULT
690 * because the user's registers will be corrupted. For instance
691 * the NIP value may have been updated but not some of the
692 * other registers. Given that we have done the access_ok
693 * and successfully read the first and last bytes of the region
694 * above, this should only happen in an out-of-memory situation
695 * or if another thread unmaps the region containing the context.
696 * We kill the task with a SIGSEGV in this situation.
699 if (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
701 set_current_blocked(&set);
702 if (restore_sigcontext(current, NULL, 0, &new_ctx->uc_mcontext))
705 /* This returns like rt_sigreturn */
706 set_thread_flag(TIF_RESTOREALL);
712 * Do a signal return; undo the signal stack.
715 SYSCALL_DEFINE0(rt_sigreturn)
717 struct pt_regs *regs = current_pt_regs();
718 struct ucontext __user *uc = (struct ucontext __user *)regs->gpr[1];
720 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
724 /* Always make any pending restarted system calls return -EINTR */
725 current->restart_block.fn = do_no_restart_syscall;
727 if (!access_ok(uc, sizeof(*uc)))
730 if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
732 set_current_blocked(&set);
734 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
736 * If there is a transactional state then throw it away.
737 * The purpose of a sigreturn is to destroy all traces of the
738 * signal frame, this includes any transactional state created
739 * within in. We only check for suspended as we can never be
740 * active in the kernel, we are active, there is nothing better to
741 * do than go ahead and Bad Thing later.
742 * The cause is not important as there will never be a
743 * recheckpoint so it's not user visible.
745 if (MSR_TM_SUSPENDED(mfmsr()))
746 tm_reclaim_current(0);
748 if (__get_user(msr, &uc->uc_mcontext.gp_regs[PT_MSR]))
750 if (MSR_TM_ACTIVE(msr)) {
751 /* We recheckpoint on return. */
752 struct ucontext __user *uc_transact;
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;
802 BUG_ON(tsk != current);
804 frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 0);
805 if (unlikely(frame == NULL))
808 err |= __put_user(&frame->info, &frame->pinfo);
809 err |= __put_user(&frame->uc, &frame->puc);
810 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
814 /* Create the ucontext. */
815 err |= __put_user(0, &frame->uc.uc_flags);
816 err |= __save_altstack(&frame->uc.uc_stack, regs->gpr[1]);
817 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
818 if (MSR_TM_ACTIVE(regs->msr)) {
819 /* The ucontext_t passed to userland points to the second
820 * ucontext_t (for transactional state) with its uc_link ptr.
822 err |= __put_user(&frame->uc_transact, &frame->uc.uc_link);
823 err |= setup_tm_sigcontexts(&frame->uc.uc_mcontext,
824 &frame->uc_transact.uc_mcontext,
825 tsk, ksig->sig, NULL,
826 (unsigned long)ksig->ka.sa.sa_handler);
830 err |= __put_user(0, &frame->uc.uc_link);
831 err |= setup_sigcontext(&frame->uc.uc_mcontext, tsk, ksig->sig,
832 NULL, (unsigned long)ksig->ka.sa.sa_handler,
835 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
839 /* Make sure signal handler doesn't get spurious FP exceptions */
840 tsk->thread.fp_state.fpscr = 0;
842 /* Set up to return from userspace. */
843 if (vdso64_rt_sigtramp && tsk->mm->context.vdso_base) {
844 regs->link = tsk->mm->context.vdso_base + vdso64_rt_sigtramp;
846 err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
849 regs->link = (unsigned long) &frame->tramp[0];
852 /* Allocate a dummy caller frame for the signal handler. */
853 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
854 err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
856 /* Set up "regs" so we "return" to the signal handler. */
857 if (is_elf2_task()) {
858 regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
859 regs->gpr[12] = regs->nip;
861 /* Handler is *really* a pointer to the function descriptor for
862 * the signal routine. The first entry in the function
863 * descriptor is the entry address of signal and the second
864 * entry is the TOC value we need to use.
866 func_descr_t __user *funct_desc_ptr =
867 (func_descr_t __user *) ksig->ka.sa.sa_handler;
869 err |= get_user(regs->nip, &funct_desc_ptr->entry);
870 err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
873 /* enter the signal handler in native-endian mode */
874 regs->msr &= ~MSR_LE;
875 regs->msr |= (MSR_KERNEL & MSR_LE);
876 regs->gpr[1] = newsp;
877 regs->gpr[3] = ksig->sig;
879 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
880 err |= get_user(regs->gpr[4], (unsigned long __user *)&frame->pinfo);
881 err |= get_user(regs->gpr[5], (unsigned long __user *)&frame->puc);
882 regs->gpr[6] = (unsigned long) frame;
884 regs->gpr[4] = (unsigned long)&frame->uc.uc_mcontext;
892 if (show_unhandled_signals)
893 printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
894 tsk->comm, tsk->pid, "setup_rt_frame",
895 (long)frame, regs->nip, regs->link);