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1/*
2 * linux/arch/parisc/kernel/signal.c: Architecture-specific signal
3 * handling support.
4 *
5 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
6 * Copyright (C) 2000 Linuxcare, Inc.
7 *
8 * Based on the ia64, i386, and alpha versions.
9 *
10 * Like the IA-64, we are a recent enough port (we are *starting*
11 * with glibc2.2) that we do not need to support the old non-realtime
12 * Linux signals. Therefore we don't. HP/UX signals will go in
13 * arch/parisc/hpux/signal.c when we figure out how to do them.
14 */
15
16#include <linux/sched.h>
17#include <linux/mm.h>
18#include <linux/smp.h>
19#include <linux/kernel.h>
20#include <linux/signal.h>
21#include <linux/errno.h>
22#include <linux/wait.h>
23#include <linux/ptrace.h>
24#include <linux/tracehook.h>
25#include <linux/unistd.h>
26#include <linux/stddef.h>
27#include <linux/compat.h>
28#include <linux/elf.h>
29#include <asm/ucontext.h>
30#include <asm/rt_sigframe.h>
31#include <asm/uaccess.h>
32#include <asm/pgalloc.h>
33#include <asm/cacheflush.h>
34#include <asm/asm-offsets.h>
35
36#ifdef CONFIG_COMPAT
37#include "signal32.h"
38#endif
39
40#define DEBUG_SIG 0
41#define DEBUG_SIG_LEVEL 2
42
43#if DEBUG_SIG
44#define DBG(LEVEL, ...) \
45 ((DEBUG_SIG_LEVEL >= LEVEL) \
46 ? printk(__VA_ARGS__) : (void) 0)
47#else
48#define DBG(LEVEL, ...)
49#endif
50
51/* gcc will complain if a pointer is cast to an integer of different
52 * size. If you really need to do this (and we do for an ELF32 user
53 * application in an ELF64 kernel) then you have to do a cast to an
54 * integer of the same size first. The A() macro accomplishes
55 * this. */
56#define A(__x) ((unsigned long)(__x))
57
58/*
59 * Atomically swap in the new signal mask, and wait for a signal.
60 */
61#ifdef CONFIG_64BIT
62#include "sys32.h"
63#endif
64
65/*
66 * Do a signal return - restore sigcontext.
67 */
68
69/* Trampoline for calling rt_sigreturn() */
70#define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */
71#define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */
72#define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */
73#define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */
74#define INSN_NOP 0x08000240 /* nop */
75/* For debugging */
76#define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */
77
78static long
79restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
80{
81 long err = 0;
82
83 err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr));
84 err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr));
85 err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq));
86 err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq));
87 err |= __get_user(regs->sar, &sc->sc_sar);
88 DBG(2,"restore_sigcontext: iaoq is 0x%#lx / 0x%#lx\n",
89 regs->iaoq[0],regs->iaoq[1]);
90 DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]);
91 return err;
92}
93
94void
95sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
96{
97 struct rt_sigframe __user *frame;
98 sigset_t set;
99 unsigned long usp = (regs->gr[30] & ~(0x01UL));
100 unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE;
101#ifdef CONFIG_64BIT
102 compat_sigset_t compat_set;
103 struct compat_rt_sigframe __user * compat_frame;
104
105 if (is_compat_task())
106 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
107#endif
108
109 current_thread_info()->restart_block.fn = do_no_restart_syscall;
110
111 /* Unwind the user stack to get the rt_sigframe structure. */
112 frame = (struct rt_sigframe __user *)
113 (usp - sigframe_size);
114 DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
115
116#ifdef CONFIG_64BIT
117 compat_frame = (struct compat_rt_sigframe __user *)frame;
118
119 if (is_compat_task()) {
120 DBG(2,"sys_rt_sigreturn: ELF32 process.\n");
121 if (__copy_from_user(&compat_set, &compat_frame->uc.uc_sigmask, sizeof(compat_set)))
122 goto give_sigsegv;
123 sigset_32to64(&set,&compat_set);
124 } else
125#endif
126 {
127 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
128 goto give_sigsegv;
129 }
130
131 set_current_blocked(&set);
132
133 /* Good thing we saved the old gr[30], eh? */
134#ifdef CONFIG_64BIT
135 if (is_compat_task()) {
136 DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n",
137 &compat_frame->uc.uc_mcontext);
138// FIXME: Load upper half from register file
139 if (restore_sigcontext32(&compat_frame->uc.uc_mcontext,
140 &compat_frame->regs, regs))
141 goto give_sigsegv;
142 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
143 usp, &compat_frame->uc.uc_stack);
144 if (do_sigaltstack32(&compat_frame->uc.uc_stack, NULL, usp) == -EFAULT)
145 goto give_sigsegv;
146 } else
147#endif
148 {
149 DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n",
150 &frame->uc.uc_mcontext);
151 if (restore_sigcontext(&frame->uc.uc_mcontext, regs))
152 goto give_sigsegv;
153 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
154 usp, &frame->uc.uc_stack);
155 if (do_sigaltstack(&frame->uc.uc_stack, NULL, usp) == -EFAULT)
156 goto give_sigsegv;
157 }
158
159
160
161 /* If we are on the syscall path IAOQ will not be restored, and
162 * if we are on the interrupt path we must not corrupt gr31.
163 */
164 if (in_syscall)
165 regs->gr[31] = regs->iaoq[0];
166#if DEBUG_SIG
167 DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]);
168 show_regs(regs);
169#endif
170 return;
171
172give_sigsegv:
173 DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n");
174 force_sig(SIGSEGV, current);
175 return;
176}
177
178/*
179 * Set up a signal frame.
180 */
181
182static inline void __user *
183get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
184{
185 /*FIXME: ELF32 vs. ELF64 has different frame_size, but since we
186 don't use the parameter it doesn't matter */
187
188 DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
189 (unsigned long)ka, sp, frame_size);
190
191 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
192 sp = current->sas_ss_sp; /* Stacks grow up! */
193
194 DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
195 return (void __user *) sp; /* Stacks grow up. Fun. */
196}
197
198static long
199setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
200
201{
202 unsigned long flags = 0;
203 long err = 0;
204
205 if (on_sig_stack((unsigned long) sc))
206 flags |= PARISC_SC_FLAG_ONSTACK;
207 if (in_syscall) {
208 flags |= PARISC_SC_FLAG_IN_SYSCALL;
209 /* regs->iaoq is undefined in the syscall return path */
210 err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
211 err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
212 err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
213 err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
214 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
215 regs->gr[31], regs->gr[31]+4);
216 } else {
217 err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
218 err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
219 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
220 regs->iaoq[0], regs->iaoq[1]);
221 }
222
223 err |= __put_user(flags, &sc->sc_flags);
224 err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
225 err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
226 err |= __put_user(regs->sar, &sc->sc_sar);
227 DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
228
229 return err;
230}
231
232static long
233setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
234 sigset_t *set, struct pt_regs *regs, int in_syscall)
235{
236 struct rt_sigframe __user *frame;
237 unsigned long rp, usp;
238 unsigned long haddr, sigframe_size;
239 int err = 0;
240#ifdef CONFIG_64BIT
241 compat_int_t compat_val;
242 struct compat_rt_sigframe __user * compat_frame;
243 compat_sigset_t compat_set;
244#endif
245
246 usp = (regs->gr[30] & ~(0x01UL));
247 /*FIXME: frame_size parameter is unused, remove it. */
248 frame = get_sigframe(ka, usp, sizeof(*frame));
249
250 DBG(1,"SETUP_RT_FRAME: START\n");
251 DBG(1,"setup_rt_frame: frame %p info %p\n", frame, info);
252
253
254#ifdef CONFIG_64BIT
255
256 compat_frame = (struct compat_rt_sigframe __user *)frame;
257
258 if (is_compat_task()) {
259 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
260 err |= copy_siginfo_to_user32(&compat_frame->info, info);
261 DBG(1,"SETUP_RT_FRAME: 1\n");
262 compat_val = (compat_int_t)current->sas_ss_sp;
263 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_sp);
264 DBG(1,"SETUP_RT_FRAME: 2\n");
265 compat_val = (compat_int_t)current->sas_ss_size;
266 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_size);
267 DBG(1,"SETUP_RT_FRAME: 3\n");
268 compat_val = sas_ss_flags(regs->gr[30]);
269 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_flags);
270 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
271 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
272 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
273 &compat_frame->regs, regs, in_syscall);
274 sigset_64to32(&compat_set,set);
275 err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
276 } else
277#endif
278 {
279 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
280 err |= copy_siginfo_to_user(&frame->info, info);
281 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
282 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
283 err |= __put_user(sas_ss_flags(regs->gr[30]),
284 &frame->uc.uc_stack.ss_flags);
285 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
286 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
287 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
288 /* FIXME: Should probably be converted as well for the compat case */
289 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
290 }
291
292 if (err)
293 goto give_sigsegv;
294
295 /* Set up to return from userspace. If provided, use a stub
296 already in userspace. The first words of tramp are used to
297 save the previous sigrestartblock trampoline that might be
298 on the stack. We start the sigreturn trampoline at
299 SIGRESTARTBLOCK_TRAMP+X. */
300 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
301 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
302 err |= __put_user(INSN_LDI_R20,
303 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
304 err |= __put_user(INSN_BLE_SR2_R0,
305 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
306 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
307
308#if DEBUG_SIG
309 /* Assert that we're flushing in the correct space... */
310 {
311 int sid;
312 asm ("mfsp %%sr3,%0" : "=r" (sid));
313 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
314 sid, frame->tramp);
315 }
316#endif
317
318 flush_user_dcache_range((unsigned long) &frame->tramp[0],
319 (unsigned long) &frame->tramp[TRAMP_SIZE]);
320 flush_user_icache_range((unsigned long) &frame->tramp[0],
321 (unsigned long) &frame->tramp[TRAMP_SIZE]);
322
323 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
324 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
325 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
326 */
327 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
328
329 if (err)
330 goto give_sigsegv;
331
332 haddr = A(ka->sa.sa_handler);
333 /* The sa_handler may be a pointer to a function descriptor */
334#ifdef CONFIG_64BIT
335 if (is_compat_task()) {
336#endif
337 if (haddr & PA_PLABEL_FDESC) {
338 Elf32_Fdesc fdesc;
339 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
340
341 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
342
343 if (err)
344 goto give_sigsegv;
345
346 haddr = fdesc.addr;
347 regs->gr[19] = fdesc.gp;
348 }
349#ifdef CONFIG_64BIT
350 } else {
351 Elf64_Fdesc fdesc;
352 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
353
354 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
355
356 if (err)
357 goto give_sigsegv;
358
359 haddr = fdesc.addr;
360 regs->gr[19] = fdesc.gp;
361 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
362 haddr, regs->gr[19], in_syscall);
363 }
364#endif
365
366 /* The syscall return path will create IAOQ values from r31.
367 */
368 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
369#ifdef CONFIG_64BIT
370 if (is_compat_task())
371 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
372#endif
373 if (in_syscall) {
374 regs->gr[31] = haddr;
375#ifdef CONFIG_64BIT
376 if (!test_thread_flag(TIF_32BIT))
377 sigframe_size |= 1;
378#endif
379 } else {
380 unsigned long psw = USER_PSW;
381#ifdef CONFIG_64BIT
382 if (!test_thread_flag(TIF_32BIT))
383 psw |= PSW_W;
384#endif
385
386 /* If we are singlestepping, arrange a trap to be delivered
387 when we return to userspace. Note the semantics -- we
388 should trap before the first insn in the handler is
389 executed. Ref:
390 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
391 */
392 if (pa_psw(current)->r) {
393 pa_psw(current)->r = 0;
394 psw |= PSW_R;
395 mtctl(-1, 0);
396 }
397
398 regs->gr[0] = psw;
399 regs->iaoq[0] = haddr | 3;
400 regs->iaoq[1] = regs->iaoq[0] + 4;
401 }
402
403 regs->gr[2] = rp; /* userland return pointer */
404 regs->gr[26] = sig; /* signal number */
405
406#ifdef CONFIG_64BIT
407 if (is_compat_task()) {
408 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
409 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
410 } else
411#endif
412 {
413 regs->gr[25] = A(&frame->info); /* siginfo pointer */
414 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
415 }
416
417 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
418 regs->gr[30], sigframe_size,
419 regs->gr[30] + sigframe_size);
420 /* Raise the user stack pointer to make a proper call frame. */
421 regs->gr[30] = (A(frame) + sigframe_size);
422
423
424 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
425 current->comm, current->pid, frame, regs->gr[30],
426 regs->iaoq[0], regs->iaoq[1], rp);
427
428 return 1;
429
430give_sigsegv:
431 DBG(1,"setup_rt_frame: sending SIGSEGV\n");
432 force_sigsegv(sig, current);
433 return 0;
434}
435
436/*
437 * OK, we're invoking a handler.
438 */
439
440static long
441handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
442 struct pt_regs *regs, int in_syscall)
443{
444 sigset_t *oldset = sigmask_to_save();
445 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
446 sig, ka, info, oldset, regs);
447
448 /* Set up the stack frame */
449 if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
450 return 0;
451
452 signal_delivered(sig, info, ka, regs,
453 test_thread_flag(TIF_SINGLESTEP) ||
454 test_thread_flag(TIF_BLOCKSTEP));
455
456 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
457 regs->gr[28]);
458
459 return 1;
460}
461
462static inline void
463syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
464{
465 /* Check the return code */
466 switch (regs->gr[28]) {
467 case -ERESTART_RESTARTBLOCK:
468 case -ERESTARTNOHAND:
469 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
470 regs->gr[28] = -EINTR;
471 break;
472
473 case -ERESTARTSYS:
474 if (!(ka->sa.sa_flags & SA_RESTART)) {
475 DBG(1,"ERESTARTSYS: putting -EINTR\n");
476 regs->gr[28] = -EINTR;
477 break;
478 }
479 /* fallthrough */
480 case -ERESTARTNOINTR:
481 /* A syscall is just a branch, so all
482 * we have to do is fiddle the return pointer.
483 */
484 regs->gr[31] -= 8; /* delayed branching */
485 /* Preserve original r28. */
486 regs->gr[28] = regs->orig_r28;
487 break;
488 }
489}
490
491static inline void
492insert_restart_trampoline(struct pt_regs *regs)
493{
494 switch(regs->gr[28]) {
495 case -ERESTART_RESTARTBLOCK: {
496 /* Restart the system call - no handlers present */
497 unsigned int *usp = (unsigned int *)regs->gr[30];
498
499 /* Setup a trampoline to restart the syscall
500 * with __NR_restart_syscall
501 *
502 * 0: <return address (orig r31)>
503 * 4: <2nd half for 64-bit>
504 * 8: ldw 0(%sp), %r31
505 * 12: be 0x100(%sr2, %r0)
506 * 16: ldi __NR_restart_syscall, %r20
507 */
508#ifdef CONFIG_64BIT
509 put_user(regs->gr[31] >> 32, &usp[0]);
510 put_user(regs->gr[31] & 0xffffffff, &usp[1]);
511 put_user(0x0fc010df, &usp[2]);
512#else
513 put_user(regs->gr[31], &usp[0]);
514 put_user(0x0fc0109f, &usp[2]);
515#endif
516 put_user(0xe0008200, &usp[3]);
517 put_user(0x34140000, &usp[4]);
518
519 /* Stack is 64-byte aligned, and we only need
520 * to flush 1 cache line.
521 * Flushing one cacheline is cheap.
522 * "sync" on bigger (> 4 way) boxes is not.
523 */
524 flush_user_dcache_range(regs->gr[30], regs->gr[30] + 4);
525 flush_user_icache_range(regs->gr[30], regs->gr[30] + 4);
526
527 regs->gr[31] = regs->gr[30] + 8;
528 /* Preserve original r28. */
529 regs->gr[28] = regs->orig_r28;
530
531 return;
532 }
533 case -ERESTARTNOHAND:
534 case -ERESTARTSYS:
535 case -ERESTARTNOINTR: {
536 /* Hooray for delayed branching. We don't
537 * have to restore %r20 (the system call
538 * number) because it gets loaded in the delay
539 * slot of the branch external instruction.
540 */
541 regs->gr[31] -= 8;
542 /* Preserve original r28. */
543 regs->gr[28] = regs->orig_r28;
544
545 return;
546 }
547 default:
548 break;
549 }
550}
551
552/*
553 * Note that 'init' is a special process: it doesn't get signals it doesn't
554 * want to handle. Thus you cannot kill init even with a SIGKILL even by
555 * mistake.
556 *
557 * We need to be able to restore the syscall arguments (r21-r26) to
558 * restart syscalls. Thus, the syscall path should save them in the
559 * pt_regs structure (it's okay to do so since they are caller-save
560 * registers). As noted below, the syscall number gets restored for
561 * us due to the magic of delayed branching.
562 */
563asmlinkage void
564do_signal(struct pt_regs *regs, long in_syscall)
565{
566 siginfo_t info;
567 struct k_sigaction ka;
568 int signr;
569
570 DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
571 regs, regs->sr[7], in_syscall);
572
573 /* Everyone else checks to see if they are in kernel mode at
574 this point and exits if that's the case. I'm not sure why
575 we would be called in that case, but for some reason we
576 are. */
577
578 /* May need to force signal if handle_signal failed to deliver */
579 while (1) {
580 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
581 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
582
583 if (signr <= 0)
584 break;
585
586 /* Restart a system call if necessary. */
587 if (in_syscall)
588 syscall_restart(regs, &ka);
589
590 /* Whee! Actually deliver the signal. If the
591 delivery failed, we need to continue to iterate in
592 this loop so we can deliver the SIGSEGV... */
593 if (handle_signal(signr, &info, &ka, regs, in_syscall))
594 return;
595 }
596 /* end of while(1) looping forever if we can't force a signal */
597
598 /* Did we come from a system call? */
599 if (in_syscall)
600 insert_restart_trampoline(regs);
601
602 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
603 regs->gr[28]);
604
605 restore_saved_sigmask();
606}
607
608void do_notify_resume(struct pt_regs *regs, long in_syscall)
609{
610 if (test_thread_flag(TIF_SIGPENDING))
611 do_signal(regs, in_syscall);
612
613 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
614 clear_thread_flag(TIF_NOTIFY_RESUME);
615 tracehook_notify_resume(regs);
616 }
617}
1/*
2 * linux/arch/parisc/kernel/signal.c: Architecture-specific signal
3 * handling support.
4 *
5 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
6 * Copyright (C) 2000 Linuxcare, Inc.
7 *
8 * Based on the ia64, i386, and alpha versions.
9 *
10 * Like the IA-64, we are a recent enough port (we are *starting*
11 * with glibc2.2) that we do not need to support the old non-realtime
12 * Linux signals. Therefore we don't. HP/UX signals will go in
13 * arch/parisc/hpux/signal.c when we figure out how to do them.
14 */
15
16#include <linux/sched.h>
17#include <linux/mm.h>
18#include <linux/smp.h>
19#include <linux/kernel.h>
20#include <linux/signal.h>
21#include <linux/errno.h>
22#include <linux/wait.h>
23#include <linux/ptrace.h>
24#include <linux/tracehook.h>
25#include <linux/unistd.h>
26#include <linux/stddef.h>
27#include <linux/compat.h>
28#include <linux/elf.h>
29#include <asm/ucontext.h>
30#include <asm/rt_sigframe.h>
31#include <asm/uaccess.h>
32#include <asm/pgalloc.h>
33#include <asm/cacheflush.h>
34#include <asm/asm-offsets.h>
35
36#ifdef CONFIG_COMPAT
37#include "signal32.h"
38#endif
39
40#define DEBUG_SIG 0
41#define DEBUG_SIG_LEVEL 2
42
43#if DEBUG_SIG
44#define DBG(LEVEL, ...) \
45 ((DEBUG_SIG_LEVEL >= LEVEL) \
46 ? printk(__VA_ARGS__) : (void) 0)
47#else
48#define DBG(LEVEL, ...)
49#endif
50
51
52#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
53
54/* gcc will complain if a pointer is cast to an integer of different
55 * size. If you really need to do this (and we do for an ELF32 user
56 * application in an ELF64 kernel) then you have to do a cast to an
57 * integer of the same size first. The A() macro accomplishes
58 * this. */
59#define A(__x) ((unsigned long)(__x))
60
61/*
62 * Atomically swap in the new signal mask, and wait for a signal.
63 */
64#ifdef CONFIG_64BIT
65#include "sys32.h"
66#endif
67
68/*
69 * Do a signal return - restore sigcontext.
70 */
71
72/* Trampoline for calling rt_sigreturn() */
73#define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */
74#define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */
75#define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */
76#define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */
77#define INSN_NOP 0x08000240 /* nop */
78/* For debugging */
79#define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */
80
81static long
82restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
83{
84 long err = 0;
85
86 err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr));
87 err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr));
88 err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq));
89 err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq));
90 err |= __get_user(regs->sar, &sc->sc_sar);
91 DBG(2,"restore_sigcontext: iaoq is 0x%#lx / 0x%#lx\n",
92 regs->iaoq[0],regs->iaoq[1]);
93 DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]);
94 return err;
95}
96
97void
98sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
99{
100 struct rt_sigframe __user *frame;
101 sigset_t set;
102 unsigned long usp = (regs->gr[30] & ~(0x01UL));
103 unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE;
104#ifdef CONFIG_64BIT
105 compat_sigset_t compat_set;
106 struct compat_rt_sigframe __user * compat_frame;
107
108 if (is_compat_task())
109 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
110#endif
111
112
113 /* Unwind the user stack to get the rt_sigframe structure. */
114 frame = (struct rt_sigframe __user *)
115 (usp - sigframe_size);
116 DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
117
118#ifdef CONFIG_64BIT
119 compat_frame = (struct compat_rt_sigframe __user *)frame;
120
121 if (is_compat_task()) {
122 DBG(2,"sys_rt_sigreturn: ELF32 process.\n");
123 if (__copy_from_user(&compat_set, &compat_frame->uc.uc_sigmask, sizeof(compat_set)))
124 goto give_sigsegv;
125 sigset_32to64(&set,&compat_set);
126 } else
127#endif
128 {
129 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
130 goto give_sigsegv;
131 }
132
133 sigdelsetmask(&set, ~_BLOCKABLE);
134 spin_lock_irq(¤t->sighand->siglock);
135 current->blocked = set;
136 recalc_sigpending();
137 spin_unlock_irq(¤t->sighand->siglock);
138
139 /* Good thing we saved the old gr[30], eh? */
140#ifdef CONFIG_64BIT
141 if (is_compat_task()) {
142 DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n",
143 &compat_frame->uc.uc_mcontext);
144// FIXME: Load upper half from register file
145 if (restore_sigcontext32(&compat_frame->uc.uc_mcontext,
146 &compat_frame->regs, regs))
147 goto give_sigsegv;
148 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
149 usp, &compat_frame->uc.uc_stack);
150 if (do_sigaltstack32(&compat_frame->uc.uc_stack, NULL, usp) == -EFAULT)
151 goto give_sigsegv;
152 } else
153#endif
154 {
155 DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n",
156 &frame->uc.uc_mcontext);
157 if (restore_sigcontext(&frame->uc.uc_mcontext, regs))
158 goto give_sigsegv;
159 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
160 usp, &frame->uc.uc_stack);
161 if (do_sigaltstack(&frame->uc.uc_stack, NULL, usp) == -EFAULT)
162 goto give_sigsegv;
163 }
164
165
166
167 /* If we are on the syscall path IAOQ will not be restored, and
168 * if we are on the interrupt path we must not corrupt gr31.
169 */
170 if (in_syscall)
171 regs->gr[31] = regs->iaoq[0];
172#if DEBUG_SIG
173 DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]);
174 show_regs(regs);
175#endif
176 return;
177
178give_sigsegv:
179 DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n");
180 force_sig(SIGSEGV, current);
181 return;
182}
183
184/*
185 * Set up a signal frame.
186 */
187
188static inline void __user *
189get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
190{
191 /*FIXME: ELF32 vs. ELF64 has different frame_size, but since we
192 don't use the parameter it doesn't matter */
193
194 DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
195 (unsigned long)ka, sp, frame_size);
196
197 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
198 sp = current->sas_ss_sp; /* Stacks grow up! */
199
200 DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
201 return (void __user *) sp; /* Stacks grow up. Fun. */
202}
203
204static long
205setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
206
207{
208 unsigned long flags = 0;
209 long err = 0;
210
211 if (on_sig_stack((unsigned long) sc))
212 flags |= PARISC_SC_FLAG_ONSTACK;
213 if (in_syscall) {
214 flags |= PARISC_SC_FLAG_IN_SYSCALL;
215 /* regs->iaoq is undefined in the syscall return path */
216 err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
217 err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
218 err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
219 err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
220 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
221 regs->gr[31], regs->gr[31]+4);
222 } else {
223 err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
224 err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
225 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
226 regs->iaoq[0], regs->iaoq[1]);
227 }
228
229 err |= __put_user(flags, &sc->sc_flags);
230 err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
231 err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
232 err |= __put_user(regs->sar, &sc->sc_sar);
233 DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
234
235 return err;
236}
237
238static long
239setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
240 sigset_t *set, struct pt_regs *regs, int in_syscall)
241{
242 struct rt_sigframe __user *frame;
243 unsigned long rp, usp;
244 unsigned long haddr, sigframe_size;
245 int err = 0;
246#ifdef CONFIG_64BIT
247 compat_int_t compat_val;
248 struct compat_rt_sigframe __user * compat_frame;
249 compat_sigset_t compat_set;
250#endif
251
252 usp = (regs->gr[30] & ~(0x01UL));
253 /*FIXME: frame_size parameter is unused, remove it. */
254 frame = get_sigframe(ka, usp, sizeof(*frame));
255
256 DBG(1,"SETUP_RT_FRAME: START\n");
257 DBG(1,"setup_rt_frame: frame %p info %p\n", frame, info);
258
259
260#ifdef CONFIG_64BIT
261
262 compat_frame = (struct compat_rt_sigframe __user *)frame;
263
264 if (is_compat_task()) {
265 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
266 err |= copy_siginfo_to_user32(&compat_frame->info, info);
267 DBG(1,"SETUP_RT_FRAME: 1\n");
268 compat_val = (compat_int_t)current->sas_ss_sp;
269 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_sp);
270 DBG(1,"SETUP_RT_FRAME: 2\n");
271 compat_val = (compat_int_t)current->sas_ss_size;
272 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_size);
273 DBG(1,"SETUP_RT_FRAME: 3\n");
274 compat_val = sas_ss_flags(regs->gr[30]);
275 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_flags);
276 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
277 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
278 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
279 &compat_frame->regs, regs, in_syscall);
280 sigset_64to32(&compat_set,set);
281 err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
282 } else
283#endif
284 {
285 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
286 err |= copy_siginfo_to_user(&frame->info, info);
287 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
288 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
289 err |= __put_user(sas_ss_flags(regs->gr[30]),
290 &frame->uc.uc_stack.ss_flags);
291 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
292 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
293 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
294 /* FIXME: Should probably be converted as well for the compat case */
295 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
296 }
297
298 if (err)
299 goto give_sigsegv;
300
301 /* Set up to return from userspace. If provided, use a stub
302 already in userspace. The first words of tramp are used to
303 save the previous sigrestartblock trampoline that might be
304 on the stack. We start the sigreturn trampoline at
305 SIGRESTARTBLOCK_TRAMP+X. */
306 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
307 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
308 err |= __put_user(INSN_LDI_R20,
309 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
310 err |= __put_user(INSN_BLE_SR2_R0,
311 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
312 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
313
314#if DEBUG_SIG
315 /* Assert that we're flushing in the correct space... */
316 {
317 int sid;
318 asm ("mfsp %%sr3,%0" : "=r" (sid));
319 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
320 sid, frame->tramp);
321 }
322#endif
323
324 flush_user_dcache_range((unsigned long) &frame->tramp[0],
325 (unsigned long) &frame->tramp[TRAMP_SIZE]);
326 flush_user_icache_range((unsigned long) &frame->tramp[0],
327 (unsigned long) &frame->tramp[TRAMP_SIZE]);
328
329 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
330 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
331 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
332 */
333 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
334
335 if (err)
336 goto give_sigsegv;
337
338 haddr = A(ka->sa.sa_handler);
339 /* The sa_handler may be a pointer to a function descriptor */
340#ifdef CONFIG_64BIT
341 if (is_compat_task()) {
342#endif
343 if (haddr & PA_PLABEL_FDESC) {
344 Elf32_Fdesc fdesc;
345 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
346
347 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
348
349 if (err)
350 goto give_sigsegv;
351
352 haddr = fdesc.addr;
353 regs->gr[19] = fdesc.gp;
354 }
355#ifdef CONFIG_64BIT
356 } else {
357 Elf64_Fdesc fdesc;
358 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
359
360 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
361
362 if (err)
363 goto give_sigsegv;
364
365 haddr = fdesc.addr;
366 regs->gr[19] = fdesc.gp;
367 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
368 haddr, regs->gr[19], in_syscall);
369 }
370#endif
371
372 /* The syscall return path will create IAOQ values from r31.
373 */
374 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
375#ifdef CONFIG_64BIT
376 if (is_compat_task())
377 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
378#endif
379 if (in_syscall) {
380 regs->gr[31] = haddr;
381#ifdef CONFIG_64BIT
382 if (!test_thread_flag(TIF_32BIT))
383 sigframe_size |= 1;
384#endif
385 } else {
386 unsigned long psw = USER_PSW;
387#ifdef CONFIG_64BIT
388 if (!test_thread_flag(TIF_32BIT))
389 psw |= PSW_W;
390#endif
391
392 /* If we are singlestepping, arrange a trap to be delivered
393 when we return to userspace. Note the semantics -- we
394 should trap before the first insn in the handler is
395 executed. Ref:
396 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
397 */
398 if (pa_psw(current)->r) {
399 pa_psw(current)->r = 0;
400 psw |= PSW_R;
401 mtctl(-1, 0);
402 }
403
404 regs->gr[0] = psw;
405 regs->iaoq[0] = haddr | 3;
406 regs->iaoq[1] = regs->iaoq[0] + 4;
407 }
408
409 regs->gr[2] = rp; /* userland return pointer */
410 regs->gr[26] = sig; /* signal number */
411
412#ifdef CONFIG_64BIT
413 if (is_compat_task()) {
414 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
415 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
416 } else
417#endif
418 {
419 regs->gr[25] = A(&frame->info); /* siginfo pointer */
420 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
421 }
422
423 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
424 regs->gr[30], sigframe_size,
425 regs->gr[30] + sigframe_size);
426 /* Raise the user stack pointer to make a proper call frame. */
427 regs->gr[30] = (A(frame) + sigframe_size);
428
429
430 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
431 current->comm, current->pid, frame, regs->gr[30],
432 regs->iaoq[0], regs->iaoq[1], rp);
433
434 return 1;
435
436give_sigsegv:
437 DBG(1,"setup_rt_frame: sending SIGSEGV\n");
438 force_sigsegv(sig, current);
439 return 0;
440}
441
442/*
443 * OK, we're invoking a handler.
444 */
445
446static long
447handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
448 sigset_t *oldset, struct pt_regs *regs, int in_syscall)
449{
450 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
451 sig, ka, info, oldset, regs);
452
453 /* Set up the stack frame */
454 if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
455 return 0;
456
457 spin_lock_irq(¤t->sighand->siglock);
458 sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
459 if (!(ka->sa.sa_flags & SA_NODEFER))
460 sigaddset(¤t->blocked,sig);
461 recalc_sigpending();
462 spin_unlock_irq(¤t->sighand->siglock);
463
464 tracehook_signal_handler(sig, info, ka, regs,
465 test_thread_flag(TIF_SINGLESTEP) ||
466 test_thread_flag(TIF_BLOCKSTEP));
467
468 return 1;
469}
470
471static inline void
472syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
473{
474 /* Check the return code */
475 switch (regs->gr[28]) {
476 case -ERESTART_RESTARTBLOCK:
477 current_thread_info()->restart_block.fn =
478 do_no_restart_syscall;
479 case -ERESTARTNOHAND:
480 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
481 regs->gr[28] = -EINTR;
482 break;
483
484 case -ERESTARTSYS:
485 if (!(ka->sa.sa_flags & SA_RESTART)) {
486 DBG(1,"ERESTARTSYS: putting -EINTR\n");
487 regs->gr[28] = -EINTR;
488 break;
489 }
490 /* fallthrough */
491 case -ERESTARTNOINTR:
492 /* A syscall is just a branch, so all
493 * we have to do is fiddle the return pointer.
494 */
495 regs->gr[31] -= 8; /* delayed branching */
496 /* Preserve original r28. */
497 regs->gr[28] = regs->orig_r28;
498 break;
499 }
500}
501
502static inline void
503insert_restart_trampoline(struct pt_regs *regs)
504{
505 switch(regs->gr[28]) {
506 case -ERESTART_RESTARTBLOCK: {
507 /* Restart the system call - no handlers present */
508 unsigned int *usp = (unsigned int *)regs->gr[30];
509
510 /* Setup a trampoline to restart the syscall
511 * with __NR_restart_syscall
512 *
513 * 0: <return address (orig r31)>
514 * 4: <2nd half for 64-bit>
515 * 8: ldw 0(%sp), %r31
516 * 12: be 0x100(%sr2, %r0)
517 * 16: ldi __NR_restart_syscall, %r20
518 */
519#ifdef CONFIG_64BIT
520 put_user(regs->gr[31] >> 32, &usp[0]);
521 put_user(regs->gr[31] & 0xffffffff, &usp[1]);
522 put_user(0x0fc010df, &usp[2]);
523#else
524 put_user(regs->gr[31], &usp[0]);
525 put_user(0x0fc0109f, &usp[2]);
526#endif
527 put_user(0xe0008200, &usp[3]);
528 put_user(0x34140000, &usp[4]);
529
530 /* Stack is 64-byte aligned, and we only need
531 * to flush 1 cache line.
532 * Flushing one cacheline is cheap.
533 * "sync" on bigger (> 4 way) boxes is not.
534 */
535 flush_user_dcache_range(regs->gr[30], regs->gr[30] + 4);
536 flush_user_icache_range(regs->gr[30], regs->gr[30] + 4);
537
538 regs->gr[31] = regs->gr[30] + 8;
539 /* Preserve original r28. */
540 regs->gr[28] = regs->orig_r28;
541
542 return;
543 }
544 case -ERESTARTNOHAND:
545 case -ERESTARTSYS:
546 case -ERESTARTNOINTR: {
547 /* Hooray for delayed branching. We don't
548 * have to restore %r20 (the system call
549 * number) because it gets loaded in the delay
550 * slot of the branch external instruction.
551 */
552 regs->gr[31] -= 8;
553 /* Preserve original r28. */
554 regs->gr[28] = regs->orig_r28;
555
556 return;
557 }
558 default:
559 break;
560 }
561}
562
563/*
564 * Note that 'init' is a special process: it doesn't get signals it doesn't
565 * want to handle. Thus you cannot kill init even with a SIGKILL even by
566 * mistake.
567 *
568 * We need to be able to restore the syscall arguments (r21-r26) to
569 * restart syscalls. Thus, the syscall path should save them in the
570 * pt_regs structure (it's okay to do so since they are caller-save
571 * registers). As noted below, the syscall number gets restored for
572 * us due to the magic of delayed branching.
573 */
574asmlinkage void
575do_signal(struct pt_regs *regs, long in_syscall)
576{
577 siginfo_t info;
578 struct k_sigaction ka;
579 int signr;
580 sigset_t *oldset;
581
582 DBG(1,"\ndo_signal: oldset=0x%p, regs=0x%p, sr7 %#lx, in_syscall=%d\n",
583 oldset, regs, regs->sr[7], in_syscall);
584
585 /* Everyone else checks to see if they are in kernel mode at
586 this point and exits if that's the case. I'm not sure why
587 we would be called in that case, but for some reason we
588 are. */
589
590 if (test_thread_flag(TIF_RESTORE_SIGMASK))
591 oldset = ¤t->saved_sigmask;
592 else
593 oldset = ¤t->blocked;
594
595 DBG(1,"do_signal: oldset %08lx / %08lx\n",
596 oldset->sig[0], oldset->sig[1]);
597
598
599 /* May need to force signal if handle_signal failed to deliver */
600 while (1) {
601
602 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
603 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
604
605 if (signr <= 0)
606 break;
607
608 /* Restart a system call if necessary. */
609 if (in_syscall)
610 syscall_restart(regs, &ka);
611
612 /* Whee! Actually deliver the signal. If the
613 delivery failed, we need to continue to iterate in
614 this loop so we can deliver the SIGSEGV... */
615 if (handle_signal(signr, &info, &ka, oldset,
616 regs, in_syscall)) {
617 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
618 regs->gr[28]);
619 if (test_thread_flag(TIF_RESTORE_SIGMASK))
620 clear_thread_flag(TIF_RESTORE_SIGMASK);
621 return;
622 }
623 }
624 /* end of while(1) looping forever if we can't force a signal */
625
626 /* Did we come from a system call? */
627 if (in_syscall)
628 insert_restart_trampoline(regs);
629
630 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
631 regs->gr[28]);
632
633 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
634 clear_thread_flag(TIF_RESTORE_SIGMASK);
635 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
636 }
637
638 return;
639}
640
641void do_notify_resume(struct pt_regs *regs, long in_syscall)
642{
643 if (test_thread_flag(TIF_SIGPENDING) ||
644 test_thread_flag(TIF_RESTORE_SIGMASK))
645 do_signal(regs, in_syscall);
646
647 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
648 clear_thread_flag(TIF_NOTIFY_RESUME);
649 tracehook_notify_resume(regs);
650 if (current->replacement_session_keyring)
651 key_replace_session_keyring();
652 }
653}