]>
git.ipfire.org Git - people/arne_f/kernel.git/blob - arch/powerpc/kernel/signal_64.c
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(VERIFY_READ
, 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(VERIFY_READ
, v_regs
, 34 * sizeof(vector128
)))
507 if (tm_v_regs
&& !access_ok(VERIFY_READ
,
508 tm_v_regs
, 34 * sizeof(vector128
)))
510 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
511 if (v_regs
!= NULL
&& tm_v_regs
!= NULL
&& (msr
& MSR_VEC
) != 0) {
512 err
|= __copy_from_user(&tsk
->thread
.ckvr_state
, v_regs
,
513 33 * sizeof(vector128
));
514 err
|= __copy_from_user(&tsk
->thread
.vr_state
, tm_v_regs
,
515 33 * sizeof(vector128
));
516 current
->thread
.used_vr
= true;
518 else if (tsk
->thread
.used_vr
) {
519 memset(&tsk
->thread
.vr_state
, 0, 33 * sizeof(vector128
));
520 memset(&tsk
->thread
.ckvr_state
, 0, 33 * sizeof(vector128
));
522 /* Always get VRSAVE back */
523 if (v_regs
!= NULL
&& tm_v_regs
!= NULL
) {
524 err
|= __get_user(tsk
->thread
.ckvrsave
,
525 (u32 __user
*)&v_regs
[33]);
526 err
|= __get_user(tsk
->thread
.vrsave
,
527 (u32 __user
*)&tm_v_regs
[33]);
530 tsk
->thread
.vrsave
= 0;
531 tsk
->thread
.ckvrsave
= 0;
533 if (cpu_has_feature(CPU_FTR_ALTIVEC
))
534 mtspr(SPRN_VRSAVE
, tsk
->thread
.vrsave
);
535 #endif /* CONFIG_ALTIVEC */
536 /* restore floating point */
537 err
|= copy_fpr_from_user(tsk
, &tm_sc
->fp_regs
);
538 err
|= copy_ckfpr_from_user(tsk
, &sc
->fp_regs
);
541 * Get additional VSX data. Update v_regs to point after the
542 * VMX data. Copy VSX low doubleword from userspace to local
543 * buffer for formatting, then into the taskstruct.
545 if (v_regs
&& ((msr
& MSR_VSX
) != 0)) {
546 v_regs
+= ELF_NVRREG
;
547 tm_v_regs
+= ELF_NVRREG
;
548 err
|= copy_vsx_from_user(tsk
, tm_v_regs
);
549 err
|= copy_ckvsx_from_user(tsk
, v_regs
);
550 tsk
->thread
.used_vsr
= true;
552 for (i
= 0; i
< 32 ; i
++) {
553 tsk
->thread
.fp_state
.fpr
[i
][TS_VSRLOWOFFSET
] = 0;
554 tsk
->thread
.ckfp_state
.fpr
[i
][TS_VSRLOWOFFSET
] = 0;
559 /* Make sure the transaction is marked as failed */
560 tsk
->thread
.tm_texasr
|= TEXASR_FS
;
563 * Disabling preemption, since it is unsafe to be preempted
564 * with MSR[TS] set without recheckpointing.
568 /* pull in MSR TS bits from user context */
569 regs
->msr
= (regs
->msr
& ~MSR_TS_MASK
) | (msr
& MSR_TS_MASK
);
572 * Ensure that TM is enabled in regs->msr before we leave the signal
573 * handler. It could be the case that (a) user disabled the TM bit
574 * through the manipulation of the MSR bits in uc_mcontext or (b) the
575 * TM bit was disabled because a sufficient number of context switches
576 * happened whilst in the signal handler and load_tm overflowed,
577 * disabling the TM bit. In either case we can end up with an illegal
578 * TM state leading to a TM Bad Thing when we return to userspace.
581 * After regs->MSR[TS] being updated, make sure that get_user(),
582 * put_user() or similar functions are *not* called. These
583 * functions can generate page faults which will cause the process
584 * to be de-scheduled with MSR[TS] set but without calling
585 * tm_recheckpoint(). This can cause a bug.
589 /* This loads the checkpointed FP/VEC state, if used */
590 tm_recheckpoint(&tsk
->thread
);
592 msr_check_and_set(msr
& (MSR_FP
| MSR_VEC
));
594 load_fp_state(&tsk
->thread
.fp_state
);
595 regs
->msr
|= (MSR_FP
| tsk
->thread
.fpexc_mode
);
598 load_vr_state(&tsk
->thread
.vr_state
);
599 regs
->msr
|= MSR_VEC
;
609 * Setup the trampoline code on the stack
611 static long setup_trampoline(unsigned int syscall
, unsigned int __user
*tramp
)
616 /* addi r1, r1, __SIGNAL_FRAMESIZE # Pop the dummy stackframe */
617 err
|= __put_user(PPC_INST_ADDI
| __PPC_RT(R1
) | __PPC_RA(R1
) |
618 (__SIGNAL_FRAMESIZE
& 0xffff), &tramp
[0]);
619 /* li r0, __NR_[rt_]sigreturn| */
620 err
|= __put_user(PPC_INST_ADDI
| (syscall
& 0xffff), &tramp
[1]);
622 err
|= __put_user(PPC_INST_SC
, &tramp
[2]);
624 /* Minimal traceback info */
625 for (i
=TRAMP_TRACEBACK
; i
< TRAMP_SIZE
;i
++)
626 err
|= __put_user(0, &tramp
[i
]);
629 flush_icache_range((unsigned long) &tramp
[0],
630 (unsigned long) &tramp
[TRAMP_SIZE
]);
636 * Userspace code may pass a ucontext which doesn't include VSX added
637 * at the end. We need to check for this case.
639 #define UCONTEXTSIZEWITHOUTVSX \
640 (sizeof(struct ucontext) - 32*sizeof(long))
643 * Handle {get,set,swap}_context operations
645 SYSCALL_DEFINE3(swapcontext
, struct ucontext __user
*, old_ctx
,
646 struct ucontext __user
*, new_ctx
, long, ctx_size
)
650 unsigned long new_msr
= 0;
651 int ctx_has_vsx_region
= 0;
654 get_user(new_msr
, &new_ctx
->uc_mcontext
.gp_regs
[PT_MSR
]))
657 * Check that the context is not smaller than the original
658 * size (with VMX but without VSX)
660 if (ctx_size
< UCONTEXTSIZEWITHOUTVSX
)
663 * If the new context state sets the MSR VSX bits but
664 * it doesn't provide VSX state.
666 if ((ctx_size
< sizeof(struct ucontext
)) &&
669 /* Does the context have enough room to store VSX data? */
670 if (ctx_size
>= sizeof(struct ucontext
))
671 ctx_has_vsx_region
= 1;
673 if (old_ctx
!= NULL
) {
674 if (!access_ok(VERIFY_WRITE
, old_ctx
, ctx_size
)
675 || setup_sigcontext(&old_ctx
->uc_mcontext
, current
, 0, NULL
, 0,
677 || __copy_to_user(&old_ctx
->uc_sigmask
,
678 ¤t
->blocked
, sizeof(sigset_t
)))
683 if (!access_ok(VERIFY_READ
, new_ctx
, ctx_size
)
684 || __get_user(tmp
, (u8 __user
*) new_ctx
)
685 || __get_user(tmp
, (u8 __user
*) new_ctx
+ ctx_size
- 1))
689 * If we get a fault copying the context into the kernel's
690 * image of the user's registers, we can't just return -EFAULT
691 * because the user's registers will be corrupted. For instance
692 * the NIP value may have been updated but not some of the
693 * other registers. Given that we have done the access_ok
694 * and successfully read the first and last bytes of the region
695 * above, this should only happen in an out-of-memory situation
696 * or if another thread unmaps the region containing the context.
697 * We kill the task with a SIGSEGV in this situation.
700 if (__copy_from_user(&set
, &new_ctx
->uc_sigmask
, sizeof(set
)))
702 set_current_blocked(&set
);
703 if (restore_sigcontext(current
, NULL
, 0, &new_ctx
->uc_mcontext
))
706 /* This returns like rt_sigreturn */
707 set_thread_flag(TIF_RESTOREALL
);
713 * Do a signal return; undo the signal stack.
716 SYSCALL_DEFINE0(rt_sigreturn
)
718 struct pt_regs
*regs
= current_pt_regs();
719 struct ucontext __user
*uc
= (struct ucontext __user
*)regs
->gpr
[1];
721 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
725 /* Always make any pending restarted system calls return -EINTR */
726 current
->restart_block
.fn
= do_no_restart_syscall
;
728 if (!access_ok(VERIFY_READ
, uc
, sizeof(*uc
)))
731 if (__copy_from_user(&set
, &uc
->uc_sigmask
, sizeof(set
)))
733 set_current_blocked(&set
);
735 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
737 * If there is a transactional state then throw it away.
738 * The purpose of a sigreturn is to destroy all traces of the
739 * signal frame, this includes any transactional state created
740 * within in. We only check for suspended as we can never be
741 * active in the kernel, we are active, there is nothing better to
742 * do than go ahead and Bad Thing later.
743 * The cause is not important as there will never be a
744 * recheckpoint so it's not user visible.
746 if (MSR_TM_SUSPENDED(mfmsr()))
747 tm_reclaim_current(0);
749 if (__get_user(msr
, &uc
->uc_mcontext
.gp_regs
[PT_MSR
]))
751 if (MSR_TM_ACTIVE(msr
)) {
752 /* We recheckpoint on return. */
753 struct ucontext __user
*uc_transact
;
754 if (__get_user(uc_transact
, &uc
->uc_link
))
756 if (restore_tm_sigcontexts(current
, &uc
->uc_mcontext
,
757 &uc_transact
->uc_mcontext
))
761 /* Fall through, for non-TM restore */
763 if (restore_sigcontext(current
, NULL
, 1, &uc
->uc_mcontext
))
766 if (restore_altstack(&uc
->uc_stack
))
769 set_thread_flag(TIF_RESTOREALL
);
773 if (show_unhandled_signals
)
774 printk_ratelimited(regs
->msr
& MSR_64BIT
? fmt64
: fmt32
,
775 current
->comm
, current
->pid
, "rt_sigreturn",
776 (long)uc
, regs
->nip
, regs
->link
);
778 force_sig(SIGSEGV
, current
);
782 int handle_rt_signal64(struct ksignal
*ksig
, sigset_t
*set
,
783 struct task_struct
*tsk
)
785 struct rt_sigframe __user
*frame
;
786 unsigned long newsp
= 0;
788 struct pt_regs
*regs
= tsk
->thread
.regs
;
790 BUG_ON(tsk
!= current
);
792 frame
= get_sigframe(ksig
, get_tm_stackpointer(tsk
), sizeof(*frame
), 0);
793 if (unlikely(frame
== NULL
))
796 err
|= __put_user(&frame
->info
, &frame
->pinfo
);
797 err
|= __put_user(&frame
->uc
, &frame
->puc
);
798 err
|= copy_siginfo_to_user(&frame
->info
, &ksig
->info
);
802 /* Create the ucontext. */
803 err
|= __put_user(0, &frame
->uc
.uc_flags
);
804 err
|= __save_altstack(&frame
->uc
.uc_stack
, regs
->gpr
[1]);
805 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
806 if (MSR_TM_ACTIVE(regs
->msr
)) {
807 /* The ucontext_t passed to userland points to the second
808 * ucontext_t (for transactional state) with its uc_link ptr.
810 err
|= __put_user(&frame
->uc_transact
, &frame
->uc
.uc_link
);
811 err
|= setup_tm_sigcontexts(&frame
->uc
.uc_mcontext
,
812 &frame
->uc_transact
.uc_mcontext
,
813 tsk
, ksig
->sig
, NULL
,
814 (unsigned long)ksig
->ka
.sa
.sa_handler
);
818 err
|= __put_user(0, &frame
->uc
.uc_link
);
819 err
|= setup_sigcontext(&frame
->uc
.uc_mcontext
, tsk
, ksig
->sig
,
820 NULL
, (unsigned long)ksig
->ka
.sa
.sa_handler
,
823 err
|= __copy_to_user(&frame
->uc
.uc_sigmask
, set
, sizeof(*set
));
827 /* Make sure signal handler doesn't get spurious FP exceptions */
828 tsk
->thread
.fp_state
.fpscr
= 0;
830 /* Set up to return from userspace. */
831 if (vdso64_rt_sigtramp
&& tsk
->mm
->context
.vdso_base
) {
832 regs
->link
= tsk
->mm
->context
.vdso_base
+ vdso64_rt_sigtramp
;
834 err
|= setup_trampoline(__NR_rt_sigreturn
, &frame
->tramp
[0]);
837 regs
->link
= (unsigned long) &frame
->tramp
[0];
840 /* Allocate a dummy caller frame for the signal handler. */
841 newsp
= ((unsigned long)frame
) - __SIGNAL_FRAMESIZE
;
842 err
|= put_user(regs
->gpr
[1], (unsigned long __user
*)newsp
);
844 /* Set up "regs" so we "return" to the signal handler. */
845 if (is_elf2_task()) {
846 regs
->nip
= (unsigned long) ksig
->ka
.sa
.sa_handler
;
847 regs
->gpr
[12] = regs
->nip
;
849 /* Handler is *really* a pointer to the function descriptor for
850 * the signal routine. The first entry in the function
851 * descriptor is the entry address of signal and the second
852 * entry is the TOC value we need to use.
854 func_descr_t __user
*funct_desc_ptr
=
855 (func_descr_t __user
*) ksig
->ka
.sa
.sa_handler
;
857 err
|= get_user(regs
->nip
, &funct_desc_ptr
->entry
);
858 err
|= get_user(regs
->gpr
[2], &funct_desc_ptr
->toc
);
861 /* enter the signal handler in native-endian mode */
862 regs
->msr
&= ~MSR_LE
;
863 regs
->msr
|= (MSR_KERNEL
& MSR_LE
);
864 regs
->gpr
[1] = newsp
;
865 regs
->gpr
[3] = ksig
->sig
;
867 if (ksig
->ka
.sa
.sa_flags
& SA_SIGINFO
) {
868 err
|= get_user(regs
->gpr
[4], (unsigned long __user
*)&frame
->pinfo
);
869 err
|= get_user(regs
->gpr
[5], (unsigned long __user
*)&frame
->puc
);
870 regs
->gpr
[6] = (unsigned long) frame
;
872 regs
->gpr
[4] = (unsigned long)&frame
->uc
.uc_mcontext
;
880 if (show_unhandled_signals
)
881 printk_ratelimited(regs
->msr
& MSR_64BIT
? fmt64
: fmt32
,
882 tsk
->comm
, tsk
->pid
, "setup_rt_frame",
883 (long)frame
, regs
->nip
, regs
->link
);