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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 <linux/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
.regs
->msr
;
213 BUG_ON(tsk
!= current
);
215 BUG_ON(!MSR_TM_ACTIVE(regs
->msr
));
217 WARN_ON(tm_suspend_disabled
);
219 /* Restore checkpointed FP, VEC, and VSX bits from ckpt_regs as
220 * it contains the correct FP, VEC, VSX state after we treclaimed
221 * the transaction and giveup_all() was called on reclaiming.
223 msr
|= tsk
->thread
.ckpt_regs
.msr
& (MSR_FP
| MSR_VEC
| MSR_VSX
);
225 /* Remove TM bits from thread's MSR. The MSR in the sigcontext
226 * just indicates to userland that we were doing a transaction, but we
227 * don't want to return in transactional state. This also ensures
228 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
230 regs
->msr
&= ~MSR_TS_MASK
;
232 #ifdef CONFIG_ALTIVEC
233 err
|= __put_user(v_regs
, &sc
->v_regs
);
234 err
|= __put_user(tm_v_regs
, &tm_sc
->v_regs
);
236 /* save altivec registers */
237 if (tsk
->thread
.used_vr
) {
238 /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
239 err
|= __copy_to_user(v_regs
, &tsk
->thread
.ckvr_state
,
240 33 * sizeof(vector128
));
241 /* If VEC was enabled there are transactional VRs valid too,
242 * else they're a copy of the checkpointed VRs.
245 err
|= __copy_to_user(tm_v_regs
,
246 &tsk
->thread
.vr_state
,
247 33 * sizeof(vector128
));
249 err
|= __copy_to_user(tm_v_regs
,
250 &tsk
->thread
.ckvr_state
,
251 33 * sizeof(vector128
));
253 /* set MSR_VEC in the MSR value in the frame to indicate
254 * that sc->v_reg contains valid data.
258 /* We always copy to/from vrsave, it's 0 if we don't have or don't
261 if (cpu_has_feature(CPU_FTR_ALTIVEC
))
262 tsk
->thread
.ckvrsave
= mfspr(SPRN_VRSAVE
);
263 err
|= __put_user(tsk
->thread
.ckvrsave
, (u32 __user
*)&v_regs
[33]);
265 err
|= __put_user(tsk
->thread
.vrsave
,
266 (u32 __user
*)&tm_v_regs
[33]);
268 err
|= __put_user(tsk
->thread
.ckvrsave
,
269 (u32 __user
*)&tm_v_regs
[33]);
271 #else /* CONFIG_ALTIVEC */
272 err
|= __put_user(0, &sc
->v_regs
);
273 err
|= __put_user(0, &tm_sc
->v_regs
);
274 #endif /* CONFIG_ALTIVEC */
276 /* copy fpr regs and fpscr */
277 err
|= copy_ckfpr_to_user(&sc
->fp_regs
, tsk
);
279 err
|= copy_fpr_to_user(&tm_sc
->fp_regs
, tsk
);
281 err
|= copy_ckfpr_to_user(&tm_sc
->fp_regs
, tsk
);
285 * Copy VSX low doubleword to local buffer for formatting,
286 * then out to userspace. Update v_regs to point after the
289 if (tsk
->thread
.used_vsr
) {
290 v_regs
+= ELF_NVRREG
;
291 tm_v_regs
+= ELF_NVRREG
;
293 err
|= copy_ckvsx_to_user(v_regs
, tsk
);
296 err
|= copy_vsx_to_user(tm_v_regs
, tsk
);
298 err
|= copy_ckvsx_to_user(tm_v_regs
, tsk
);
300 /* set MSR_VSX in the MSR value in the frame to
301 * indicate that sc->vs_reg) contains valid data.
305 #endif /* CONFIG_VSX */
307 err
|= __put_user(&sc
->gp_regs
, &sc
->regs
);
308 err
|= __put_user(&tm_sc
->gp_regs
, &tm_sc
->regs
);
309 WARN_ON(!FULL_REGS(regs
));
310 err
|= __copy_to_user(&tm_sc
->gp_regs
, regs
, GP_REGS_SIZE
);
311 err
|= __copy_to_user(&sc
->gp_regs
,
312 &tsk
->thread
.ckpt_regs
, GP_REGS_SIZE
);
313 err
|= __put_user(msr
, &tm_sc
->gp_regs
[PT_MSR
]);
314 err
|= __put_user(msr
, &sc
->gp_regs
[PT_MSR
]);
315 err
|= __put_user(signr
, &sc
->signal
);
316 err
|= __put_user(handler
, &sc
->handler
);
318 err
|= __put_user(set
->sig
[0], &sc
->oldmask
);
325 * Restore the sigcontext from the signal frame.
328 static long restore_sigcontext(struct task_struct
*tsk
, sigset_t
*set
, int sig
,
329 struct sigcontext __user
*sc
)
331 #ifdef CONFIG_ALTIVEC
332 elf_vrreg_t __user
*v_regs
;
334 unsigned long err
= 0;
335 unsigned long save_r13
= 0;
337 struct pt_regs
*regs
= tsk
->thread
.regs
;
342 BUG_ON(tsk
!= current
);
344 /* If this is not a signal return, we preserve the TLS in r13 */
346 save_r13
= regs
->gpr
[13];
349 err
|= __copy_from_user(regs
->gpr
, sc
->gp_regs
, sizeof(regs
->gpr
));
350 err
|= __get_user(regs
->nip
, &sc
->gp_regs
[PT_NIP
]);
351 /* get MSR separately, transfer the LE bit if doing signal return */
352 err
|= __get_user(msr
, &sc
->gp_regs
[PT_MSR
]);
354 regs
->msr
= (regs
->msr
& ~MSR_LE
) | (msr
& MSR_LE
);
355 err
|= __get_user(regs
->orig_gpr3
, &sc
->gp_regs
[PT_ORIG_R3
]);
356 err
|= __get_user(regs
->ctr
, &sc
->gp_regs
[PT_CTR
]);
357 err
|= __get_user(regs
->link
, &sc
->gp_regs
[PT_LNK
]);
358 err
|= __get_user(regs
->xer
, &sc
->gp_regs
[PT_XER
]);
359 err
|= __get_user(regs
->ccr
, &sc
->gp_regs
[PT_CCR
]);
362 err
|= __get_user(regs
->dar
, &sc
->gp_regs
[PT_DAR
]);
363 err
|= __get_user(regs
->dsisr
, &sc
->gp_regs
[PT_DSISR
]);
364 err
|= __get_user(regs
->result
, &sc
->gp_regs
[PT_RESULT
]);
367 regs
->gpr
[13] = save_r13
;
369 err
|= __get_user(set
->sig
[0], &sc
->oldmask
);
372 * Force reload of FP/VEC.
373 * This has to be done before copying stuff into tsk->thread.fpr/vr
374 * for the reasons explained in the previous comment.
376 regs
->msr
&= ~(MSR_FP
| MSR_FE0
| MSR_FE1
| MSR_VEC
| MSR_VSX
);
378 #ifdef CONFIG_ALTIVEC
379 err
|= __get_user(v_regs
, &sc
->v_regs
);
382 if (v_regs
&& !access_ok(VERIFY_READ
, v_regs
, 34 * sizeof(vector128
)))
384 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
385 if (v_regs
!= NULL
&& (msr
& MSR_VEC
) != 0) {
386 err
|= __copy_from_user(&tsk
->thread
.vr_state
, v_regs
,
387 33 * sizeof(vector128
));
388 tsk
->thread
.used_vr
= true;
389 } else if (tsk
->thread
.used_vr
) {
390 memset(&tsk
->thread
.vr_state
, 0, 33 * sizeof(vector128
));
392 /* Always get VRSAVE back */
394 err
|= __get_user(tsk
->thread
.vrsave
, (u32 __user
*)&v_regs
[33]);
396 tsk
->thread
.vrsave
= 0;
397 if (cpu_has_feature(CPU_FTR_ALTIVEC
))
398 mtspr(SPRN_VRSAVE
, tsk
->thread
.vrsave
);
399 #endif /* CONFIG_ALTIVEC */
400 /* restore floating point */
401 err
|= copy_fpr_from_user(tsk
, &sc
->fp_regs
);
404 * Get additional VSX data. Update v_regs to point after the
405 * VMX data. Copy VSX low doubleword from userspace to local
406 * buffer for formatting, then into the taskstruct.
408 v_regs
+= ELF_NVRREG
;
409 if ((msr
& MSR_VSX
) != 0) {
410 err
|= copy_vsx_from_user(tsk
, v_regs
);
411 tsk
->thread
.used_vsr
= true;
413 for (i
= 0; i
< 32 ; i
++)
414 tsk
->thread
.fp_state
.fpr
[i
][TS_VSRLOWOFFSET
] = 0;
420 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
422 * Restore the two sigcontexts from the frame of a transactional processes.
425 static long restore_tm_sigcontexts(struct task_struct
*tsk
,
426 struct sigcontext __user
*sc
,
427 struct sigcontext __user
*tm_sc
)
429 #ifdef CONFIG_ALTIVEC
430 elf_vrreg_t __user
*v_regs
, *tm_v_regs
;
432 unsigned long err
= 0;
434 struct pt_regs
*regs
= tsk
->thread
.regs
;
439 BUG_ON(tsk
!= current
);
441 if (tm_suspend_disabled
)
445 err
|= __copy_from_user(regs
->gpr
, tm_sc
->gp_regs
, sizeof(regs
->gpr
));
446 err
|= __copy_from_user(&tsk
->thread
.ckpt_regs
, sc
->gp_regs
,
450 * TFHAR is restored from the checkpointed 'wound-back' ucontext's NIP.
451 * TEXASR was set by the signal delivery reclaim, as was TFIAR.
452 * Users doing anything abhorrent like thread-switching w/ signals for
453 * TM-Suspended code will have to back TEXASR/TFIAR up themselves.
454 * For the case of getting a signal and simply returning from it,
455 * we don't need to re-copy them here.
457 err
|= __get_user(regs
->nip
, &tm_sc
->gp_regs
[PT_NIP
]);
458 err
|= __get_user(tsk
->thread
.tm_tfhar
, &sc
->gp_regs
[PT_NIP
]);
460 /* get MSR separately, transfer the LE bit if doing signal return */
461 err
|= __get_user(msr
, &sc
->gp_regs
[PT_MSR
]);
462 /* Don't allow reserved mode. */
463 if (MSR_TM_RESV(msr
))
466 /* pull in MSR LE from user context */
467 regs
->msr
= (regs
->msr
& ~MSR_LE
) | (msr
& MSR_LE
);
469 /* The following non-GPR non-FPR non-VR state is also checkpointed: */
470 err
|= __get_user(regs
->ctr
, &tm_sc
->gp_regs
[PT_CTR
]);
471 err
|= __get_user(regs
->link
, &tm_sc
->gp_regs
[PT_LNK
]);
472 err
|= __get_user(regs
->xer
, &tm_sc
->gp_regs
[PT_XER
]);
473 err
|= __get_user(regs
->ccr
, &tm_sc
->gp_regs
[PT_CCR
]);
474 err
|= __get_user(tsk
->thread
.ckpt_regs
.ctr
,
475 &sc
->gp_regs
[PT_CTR
]);
476 err
|= __get_user(tsk
->thread
.ckpt_regs
.link
,
477 &sc
->gp_regs
[PT_LNK
]);
478 err
|= __get_user(tsk
->thread
.ckpt_regs
.xer
,
479 &sc
->gp_regs
[PT_XER
]);
480 err
|= __get_user(tsk
->thread
.ckpt_regs
.ccr
,
481 &sc
->gp_regs
[PT_CCR
]);
483 /* These regs are not checkpointed; they can go in 'regs'. */
484 err
|= __get_user(regs
->trap
, &sc
->gp_regs
[PT_TRAP
]);
485 err
|= __get_user(regs
->dar
, &sc
->gp_regs
[PT_DAR
]);
486 err
|= __get_user(regs
->dsisr
, &sc
->gp_regs
[PT_DSISR
]);
487 err
|= __get_user(regs
->result
, &sc
->gp_regs
[PT_RESULT
]);
490 * Force reload of FP/VEC.
491 * This has to be done before copying stuff into tsk->thread.fpr/vr
492 * for the reasons explained in the previous comment.
494 regs
->msr
&= ~(MSR_FP
| MSR_FE0
| MSR_FE1
| MSR_VEC
| MSR_VSX
);
496 #ifdef CONFIG_ALTIVEC
497 err
|= __get_user(v_regs
, &sc
->v_regs
);
498 err
|= __get_user(tm_v_regs
, &tm_sc
->v_regs
);
501 if (v_regs
&& !access_ok(VERIFY_READ
, v_regs
, 34 * sizeof(vector128
)))
503 if (tm_v_regs
&& !access_ok(VERIFY_READ
,
504 tm_v_regs
, 34 * sizeof(vector128
)))
506 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
507 if (v_regs
!= NULL
&& tm_v_regs
!= NULL
&& (msr
& MSR_VEC
) != 0) {
508 err
|= __copy_from_user(&tsk
->thread
.ckvr_state
, v_regs
,
509 33 * sizeof(vector128
));
510 err
|= __copy_from_user(&tsk
->thread
.vr_state
, tm_v_regs
,
511 33 * sizeof(vector128
));
512 current
->thread
.used_vr
= true;
514 else if (tsk
->thread
.used_vr
) {
515 memset(&tsk
->thread
.vr_state
, 0, 33 * sizeof(vector128
));
516 memset(&tsk
->thread
.ckvr_state
, 0, 33 * sizeof(vector128
));
518 /* Always get VRSAVE back */
519 if (v_regs
!= NULL
&& tm_v_regs
!= NULL
) {
520 err
|= __get_user(tsk
->thread
.ckvrsave
,
521 (u32 __user
*)&v_regs
[33]);
522 err
|= __get_user(tsk
->thread
.vrsave
,
523 (u32 __user
*)&tm_v_regs
[33]);
526 tsk
->thread
.vrsave
= 0;
527 tsk
->thread
.ckvrsave
= 0;
529 if (cpu_has_feature(CPU_FTR_ALTIVEC
))
530 mtspr(SPRN_VRSAVE
, tsk
->thread
.vrsave
);
531 #endif /* CONFIG_ALTIVEC */
532 /* restore floating point */
533 err
|= copy_fpr_from_user(tsk
, &tm_sc
->fp_regs
);
534 err
|= copy_ckfpr_from_user(tsk
, &sc
->fp_regs
);
537 * Get additional VSX data. Update v_regs to point after the
538 * VMX data. Copy VSX low doubleword from userspace to local
539 * buffer for formatting, then into the taskstruct.
541 if (v_regs
&& ((msr
& MSR_VSX
) != 0)) {
542 v_regs
+= ELF_NVRREG
;
543 tm_v_regs
+= ELF_NVRREG
;
544 err
|= copy_vsx_from_user(tsk
, tm_v_regs
);
545 err
|= copy_ckvsx_from_user(tsk
, v_regs
);
546 tsk
->thread
.used_vsr
= true;
548 for (i
= 0; i
< 32 ; i
++) {
549 tsk
->thread
.fp_state
.fpr
[i
][TS_VSRLOWOFFSET
] = 0;
550 tsk
->thread
.ckfp_state
.fpr
[i
][TS_VSRLOWOFFSET
] = 0;
555 /* Make sure the transaction is marked as failed */
556 tsk
->thread
.tm_texasr
|= TEXASR_FS
;
559 * Disabling preemption, since it is unsafe to be preempted
560 * with MSR[TS] set without recheckpointing.
564 /* pull in MSR TS bits from user context */
565 regs
->msr
= (regs
->msr
& ~MSR_TS_MASK
) | (msr
& MSR_TS_MASK
);
568 * Ensure that TM is enabled in regs->msr before we leave the signal
569 * handler. It could be the case that (a) user disabled the TM bit
570 * through the manipulation of the MSR bits in uc_mcontext or (b) the
571 * TM bit was disabled because a sufficient number of context switches
572 * happened whilst in the signal handler and load_tm overflowed,
573 * disabling the TM bit. In either case we can end up with an illegal
574 * TM state leading to a TM Bad Thing when we return to userspace.
577 * After regs->MSR[TS] being updated, make sure that get_user(),
578 * put_user() or similar functions are *not* called. These
579 * functions can generate page faults which will cause the process
580 * to be de-scheduled with MSR[TS] set but without calling
581 * tm_recheckpoint(). This can cause a bug.
585 /* This loads the checkpointed FP/VEC state, if used */
586 tm_recheckpoint(&tsk
->thread
);
588 msr_check_and_set(msr
& (MSR_FP
| MSR_VEC
));
590 load_fp_state(&tsk
->thread
.fp_state
);
591 regs
->msr
|= (MSR_FP
| tsk
->thread
.fpexc_mode
);
594 load_vr_state(&tsk
->thread
.vr_state
);
595 regs
->msr
|= MSR_VEC
;
605 * Setup the trampoline code on the stack
607 static long setup_trampoline(unsigned int syscall
, unsigned int __user
*tramp
)
612 /* addi r1, r1, __SIGNAL_FRAMESIZE # Pop the dummy stackframe */
613 err
|= __put_user(0x38210000UL
| (__SIGNAL_FRAMESIZE
& 0xffff), &tramp
[0]);
614 /* li r0, __NR_[rt_]sigreturn| */
615 err
|= __put_user(0x38000000UL
| (syscall
& 0xffff), &tramp
[1]);
617 err
|= __put_user(0x44000002UL
, &tramp
[2]);
619 /* Minimal traceback info */
620 for (i
=TRAMP_TRACEBACK
; i
< TRAMP_SIZE
;i
++)
621 err
|= __put_user(0, &tramp
[i
]);
624 flush_icache_range((unsigned long) &tramp
[0],
625 (unsigned long) &tramp
[TRAMP_SIZE
]);
631 * Userspace code may pass a ucontext which doesn't include VSX added
632 * at the end. We need to check for this case.
634 #define UCONTEXTSIZEWITHOUTVSX \
635 (sizeof(struct ucontext) - 32*sizeof(long))
638 * Handle {get,set,swap}_context operations
640 int sys_swapcontext(struct ucontext __user
*old_ctx
,
641 struct ucontext __user
*new_ctx
,
642 long ctx_size
, long r6
, long r7
, long r8
, struct pt_regs
*regs
)
646 unsigned long new_msr
= 0;
647 int ctx_has_vsx_region
= 0;
649 BUG_ON(regs
!= current
->thread
.regs
);
652 get_user(new_msr
, &new_ctx
->uc_mcontext
.gp_regs
[PT_MSR
]))
655 * Check that the context is not smaller than the original
656 * size (with VMX but without VSX)
658 if (ctx_size
< UCONTEXTSIZEWITHOUTVSX
)
661 * If the new context state sets the MSR VSX bits but
662 * it doesn't provide VSX state.
664 if ((ctx_size
< sizeof(struct ucontext
)) &&
667 /* Does the context have enough room to store VSX data? */
668 if (ctx_size
>= sizeof(struct ucontext
))
669 ctx_has_vsx_region
= 1;
671 if (old_ctx
!= NULL
) {
672 if (!access_ok(VERIFY_WRITE
, old_ctx
, ctx_size
)
673 || setup_sigcontext(&old_ctx
->uc_mcontext
, current
, 0, NULL
, 0,
675 || __copy_to_user(&old_ctx
->uc_sigmask
,
676 ¤t
->blocked
, sizeof(sigset_t
)))
681 if (!access_ok(VERIFY_READ
, new_ctx
, ctx_size
)
682 || __get_user(tmp
, (u8 __user
*) new_ctx
)
683 || __get_user(tmp
, (u8 __user
*) new_ctx
+ ctx_size
- 1))
687 * If we get a fault copying the context into the kernel's
688 * image of the user's registers, we can't just return -EFAULT
689 * because the user's registers will be corrupted. For instance
690 * the NIP value may have been updated but not some of the
691 * other registers. Given that we have done the access_ok
692 * and successfully read the first and last bytes of the region
693 * above, this should only happen in an out-of-memory situation
694 * or if another thread unmaps the region containing the context.
695 * We kill the task with a SIGSEGV in this situation.
698 if (__copy_from_user(&set
, &new_ctx
->uc_sigmask
, sizeof(set
)))
700 set_current_blocked(&set
);
701 if (restore_sigcontext(current
, NULL
, 0, &new_ctx
->uc_mcontext
))
704 /* This returns like rt_sigreturn */
705 set_thread_flag(TIF_RESTOREALL
);
711 * Do a signal return; undo the signal stack.
714 int sys_rt_sigreturn(unsigned long r3
, unsigned long r4
, unsigned long r5
,
715 unsigned long r6
, unsigned long r7
, unsigned long r8
,
716 struct pt_regs
*regs
)
718 struct ucontext __user
*uc
= (struct ucontext __user
*)regs
->gpr
[1];
720 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
724 BUG_ON(current
->thread
.regs
!= regs
);
726 /* Always make any pending restarted system calls return -EINTR */
727 current
->restart_block
.fn
= do_no_restart_syscall
;
729 if (!access_ok(VERIFY_READ
, uc
, sizeof(*uc
)))
732 if (__copy_from_user(&set
, &uc
->uc_sigmask
, sizeof(set
)))
734 set_current_blocked(&set
);
736 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
738 * If there is a transactional state then throw it away.
739 * The purpose of a sigreturn is to destroy all traces of the
740 * signal frame, this includes any transactional state created
741 * within in. We only check for suspended as we can never be
742 * active in the kernel, we are active, there is nothing better to
743 * do than go ahead and Bad Thing later.
744 * The cause is not important as there will never be a
745 * recheckpoint so it's not user visible.
747 if (MSR_TM_SUSPENDED(mfmsr()))
748 tm_reclaim_current(0);
750 if (__get_user(msr
, &uc
->uc_mcontext
.gp_regs
[PT_MSR
]))
752 if (MSR_TM_ACTIVE(msr
)) {
753 /* We recheckpoint on return. */
754 struct ucontext __user
*uc_transact
;
755 if (__get_user(uc_transact
, &uc
->uc_link
))
757 if (restore_tm_sigcontexts(current
, &uc
->uc_mcontext
,
758 &uc_transact
->uc_mcontext
))
764 * Fall through, for non-TM restore
766 * Unset MSR[TS] on the thread regs since MSR from user
767 * context does not have MSR active, and recheckpoint was
768 * not called since restore_tm_sigcontexts() was not called
771 * If not unsetting it, the code can RFID to userspace with
772 * MSR[TS] set, but without CPU in the proper state,
773 * causing a TM bad thing.
775 current
->thread
.regs
->msr
&= ~MSR_TS_MASK
;
776 if (restore_sigcontext(current
, NULL
, 1, &uc
->uc_mcontext
))
780 if (restore_altstack(&uc
->uc_stack
))
783 set_thread_flag(TIF_RESTOREALL
);
787 if (show_unhandled_signals
)
788 printk_ratelimited(regs
->msr
& MSR_64BIT
? fmt64
: fmt32
,
789 current
->comm
, current
->pid
, "rt_sigreturn",
790 (long)uc
, regs
->nip
, regs
->link
);
792 force_sig(SIGSEGV
, current
);
796 int handle_rt_signal64(struct ksignal
*ksig
, sigset_t
*set
,
797 struct task_struct
*tsk
)
799 struct rt_sigframe __user
*frame
;
800 unsigned long newsp
= 0;
802 struct pt_regs
*regs
= tsk
->thread
.regs
;
804 BUG_ON(tsk
!= current
);
806 frame
= get_sigframe(ksig
, get_tm_stackpointer(tsk
), sizeof(*frame
), 0);
807 if (unlikely(frame
== NULL
))
810 err
|= __put_user(&frame
->info
, &frame
->pinfo
);
811 err
|= __put_user(&frame
->uc
, &frame
->puc
);
812 err
|= copy_siginfo_to_user(&frame
->info
, &ksig
->info
);
816 /* Create the ucontext. */
817 err
|= __put_user(0, &frame
->uc
.uc_flags
);
818 err
|= __save_altstack(&frame
->uc
.uc_stack
, regs
->gpr
[1]);
819 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
820 if (MSR_TM_ACTIVE(regs
->msr
)) {
821 /* The ucontext_t passed to userland points to the second
822 * ucontext_t (for transactional state) with its uc_link ptr.
824 err
|= __put_user(&frame
->uc_transact
, &frame
->uc
.uc_link
);
825 err
|= setup_tm_sigcontexts(&frame
->uc
.uc_mcontext
,
826 &frame
->uc_transact
.uc_mcontext
,
827 tsk
, ksig
->sig
, NULL
,
828 (unsigned long)ksig
->ka
.sa
.sa_handler
);
832 err
|= __put_user(0, &frame
->uc
.uc_link
);
833 err
|= setup_sigcontext(&frame
->uc
.uc_mcontext
, tsk
, ksig
->sig
,
834 NULL
, (unsigned long)ksig
->ka
.sa
.sa_handler
,
837 err
|= __copy_to_user(&frame
->uc
.uc_sigmask
, set
, sizeof(*set
));
841 /* Make sure signal handler doesn't get spurious FP exceptions */
842 tsk
->thread
.fp_state
.fpscr
= 0;
844 /* Set up to return from userspace. */
845 if (vdso64_rt_sigtramp
&& tsk
->mm
->context
.vdso_base
) {
846 regs
->link
= tsk
->mm
->context
.vdso_base
+ vdso64_rt_sigtramp
;
848 err
|= setup_trampoline(__NR_rt_sigreturn
, &frame
->tramp
[0]);
851 regs
->link
= (unsigned long) &frame
->tramp
[0];
854 /* Allocate a dummy caller frame for the signal handler. */
855 newsp
= ((unsigned long)frame
) - __SIGNAL_FRAMESIZE
;
856 err
|= put_user(regs
->gpr
[1], (unsigned long __user
*)newsp
);
858 /* Set up "regs" so we "return" to the signal handler. */
859 if (is_elf2_task()) {
860 regs
->nip
= (unsigned long) ksig
->ka
.sa
.sa_handler
;
861 regs
->gpr
[12] = regs
->nip
;
863 /* Handler is *really* a pointer to the function descriptor for
864 * the signal routine. The first entry in the function
865 * descriptor is the entry address of signal and the second
866 * entry is the TOC value we need to use.
868 func_descr_t __user
*funct_desc_ptr
=
869 (func_descr_t __user
*) ksig
->ka
.sa
.sa_handler
;
871 err
|= get_user(regs
->nip
, &funct_desc_ptr
->entry
);
872 err
|= get_user(regs
->gpr
[2], &funct_desc_ptr
->toc
);
875 /* enter the signal handler in native-endian mode */
876 regs
->msr
&= ~MSR_LE
;
877 regs
->msr
|= (MSR_KERNEL
& MSR_LE
);
878 regs
->gpr
[1] = newsp
;
879 regs
->gpr
[3] = ksig
->sig
;
881 if (ksig
->ka
.sa
.sa_flags
& SA_SIGINFO
) {
882 err
|= get_user(regs
->gpr
[4], (unsigned long __user
*)&frame
->pinfo
);
883 err
|= get_user(regs
->gpr
[5], (unsigned long __user
*)&frame
->puc
);
884 regs
->gpr
[6] = (unsigned long) frame
;
886 regs
->gpr
[4] = (unsigned long)&frame
->uc
.uc_mcontext
;
894 if (show_unhandled_signals
)
895 printk_ratelimited(regs
->msr
& MSR_64BIT
? fmt64
: fmt32
,
896 tsk
->comm
, tsk
->pid
, "setup_rt_frame",
897 (long)frame
, regs
->nip
, regs
->link
);