]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blame - arch/parisc/kernel/signal.c
parisc: Add error checks when building up signal trampoline handler
[mirror_ubuntu-bionic-kernel.git] / arch / parisc / kernel / signal.c
CommitLineData
1da177e4
LT
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>
1da177e4
LT
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>
ecf02de5 24#include <linux/tracehook.h>
1da177e4
LT
25#include <linux/unistd.h>
26#include <linux/stddef.h>
27#include <linux/compat.h>
28#include <linux/elf.h>
1da177e4
LT
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>
0013a854 34#include <asm/asm-offsets.h>
1da177e4
LT
35
36#ifdef CONFIG_COMPAT
1da177e4
LT
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
1da177e4
LT
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
1da177e4
LT
58/*
59 * Do a signal return - restore sigcontext.
60 */
61
62/* Trampoline for calling rt_sigreturn() */
63#define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */
64#define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */
65#define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */
66#define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */
67#define INSN_NOP 0x08000240 /* nop */
68/* For debugging */
69#define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */
70
71static long
72restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
73{
74 long err = 0;
75
76 err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr));
77 err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr));
78 err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq));
79 err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq));
80 err |= __get_user(regs->sar, &sc->sc_sar);
8e33a52f 81 DBG(2,"restore_sigcontext: iaoq is %#lx / %#lx\n",
1da177e4
LT
82 regs->iaoq[0],regs->iaoq[1]);
83 DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]);
84 return err;
85}
86
87void
88sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
89{
90 struct rt_sigframe __user *frame;
1da177e4
LT
91 sigset_t set;
92 unsigned long usp = (regs->gr[30] & ~(0x01UL));
93 unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE;
a8f44e38 94#ifdef CONFIG_64BIT
1da177e4
LT
95 compat_sigset_t compat_set;
96 struct compat_rt_sigframe __user * compat_frame;
97
a3ea84fa 98 if (is_compat_task())
1da177e4
LT
99 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
100#endif
101
f56141e3 102 current->restart_block.fn = do_no_restart_syscall;
1da177e4
LT
103
104 /* Unwind the user stack to get the rt_sigframe structure. */
105 frame = (struct rt_sigframe __user *)
106 (usp - sigframe_size);
107 DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
108
00df111e
AV
109 regs->orig_r28 = 1; /* no restarts for sigreturn */
110
a8f44e38 111#ifdef CONFIG_64BIT
1da177e4
LT
112 compat_frame = (struct compat_rt_sigframe __user *)frame;
113
a3ea84fa 114 if (is_compat_task()) {
1da177e4
LT
115 DBG(2,"sys_rt_sigreturn: ELF32 process.\n");
116 if (__copy_from_user(&compat_set, &compat_frame->uc.uc_sigmask, sizeof(compat_set)))
117 goto give_sigsegv;
118 sigset_32to64(&set,&compat_set);
119 } else
120#endif
121 {
122 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
123 goto give_sigsegv;
124 }
125
ade7728b 126 set_current_blocked(&set);
1da177e4
LT
127
128 /* Good thing we saved the old gr[30], eh? */
a8f44e38 129#ifdef CONFIG_64BIT
a3ea84fa 130 if (is_compat_task()) {
1da177e4
LT
131 DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n",
132 &compat_frame->uc.uc_mcontext);
133// FIXME: Load upper half from register file
134 if (restore_sigcontext32(&compat_frame->uc.uc_mcontext,
135 &compat_frame->regs, regs))
136 goto give_sigsegv;
137 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
138 usp, &compat_frame->uc.uc_stack);
6e26aab9 139 if (compat_restore_altstack(&compat_frame->uc.uc_stack))
1da177e4
LT
140 goto give_sigsegv;
141 } else
142#endif
143 {
144 DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n",
145 &frame->uc.uc_mcontext);
146 if (restore_sigcontext(&frame->uc.uc_mcontext, regs))
147 goto give_sigsegv;
148 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
149 usp, &frame->uc.uc_stack);
6e26aab9 150 if (restore_altstack(&frame->uc.uc_stack))
1da177e4
LT
151 goto give_sigsegv;
152 }
153
154
155
156 /* If we are on the syscall path IAOQ will not be restored, and
157 * if we are on the interrupt path we must not corrupt gr31.
158 */
159 if (in_syscall)
160 regs->gr[31] = regs->iaoq[0];
161#if DEBUG_SIG
162 DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]);
163 show_regs(regs);
164#endif
165 return;
166
167give_sigsegv:
168 DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n");
67bace72 169 force_sig(SIGSEGV, current);
1da177e4
LT
170 return;
171}
172
173/*
174 * Set up a signal frame.
175 */
176
177static inline void __user *
178get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
179{
180 /*FIXME: ELF32 vs. ELF64 has different frame_size, but since we
181 don't use the parameter it doesn't matter */
182
183 DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
184 (unsigned long)ka, sp, frame_size);
185
ad30f3ff
JDA
186 /* Align alternate stack and reserve 64 bytes for the signal
187 handler's frame marker. */
d09042da 188 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
ad30f3ff 189 sp = (current->sas_ss_sp + 0x7f) & ~0x3f; /* Stacks grow up! */
1da177e4
LT
190
191 DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
192 return (void __user *) sp; /* Stacks grow up. Fun. */
193}
194
195static long
196setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
197
198{
199 unsigned long flags = 0;
200 long err = 0;
201
202 if (on_sig_stack((unsigned long) sc))
203 flags |= PARISC_SC_FLAG_ONSTACK;
204 if (in_syscall) {
205 flags |= PARISC_SC_FLAG_IN_SYSCALL;
206 /* regs->iaoq is undefined in the syscall return path */
207 err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
208 err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
209 err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
210 err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
211 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
212 regs->gr[31], regs->gr[31]+4);
213 } else {
214 err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
215 err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
216 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
217 regs->iaoq[0], regs->iaoq[1]);
218 }
219
220 err |= __put_user(flags, &sc->sc_flags);
221 err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
222 err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
223 err |= __put_user(regs->sar, &sc->sc_sar);
224 DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
225
226 return err;
227}
228
229static long
e4dc894b
RW
230setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs,
231 int in_syscall)
1da177e4
LT
232{
233 struct rt_sigframe __user *frame;
234 unsigned long rp, usp;
235 unsigned long haddr, sigframe_size;
1da177e4 236 int err = 0;
a8f44e38 237#ifdef CONFIG_64BIT
1da177e4
LT
238 struct compat_rt_sigframe __user * compat_frame;
239 compat_sigset_t compat_set;
240#endif
241
242 usp = (regs->gr[30] & ~(0x01UL));
243 /*FIXME: frame_size parameter is unused, remove it. */
e4dc894b 244 frame = get_sigframe(&ksig->ka, usp, sizeof(*frame));
1da177e4
LT
245
246 DBG(1,"SETUP_RT_FRAME: START\n");
e4dc894b 247 DBG(1,"setup_rt_frame: frame %p info %p\n", frame, ksig->info);
1da177e4
LT
248
249
a8f44e38 250#ifdef CONFIG_64BIT
1da177e4
LT
251
252 compat_frame = (struct compat_rt_sigframe __user *)frame;
253
a3ea84fa 254 if (is_compat_task()) {
1da177e4 255 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
e4dc894b 256 err |= copy_siginfo_to_user32(&compat_frame->info, &ksig->info);
6e26aab9 257 err |= __compat_save_altstack( &compat_frame->uc.uc_stack, regs->gr[30]);
1da177e4
LT
258 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
259 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
260 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
261 &compat_frame->regs, regs, in_syscall);
262 sigset_64to32(&compat_set,set);
263 err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
264 } else
265#endif
266 {
267 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
e4dc894b 268 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
6e26aab9 269 err |= __save_altstack(&frame->uc.uc_stack, regs->gr[30]);
1da177e4
LT
270 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
271 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
272 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
25985edc 273 /* FIXME: Should probably be converted as well for the compat case */
1da177e4
LT
274 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
275 }
276
277 if (err)
e4dc894b 278 return -EFAULT;
1da177e4
LT
279
280 /* Set up to return from userspace. If provided, use a stub
281 already in userspace. The first words of tramp are used to
282 save the previous sigrestartblock trampoline that might be
283 on the stack. We start the sigreturn trampoline at
284 SIGRESTARTBLOCK_TRAMP+X. */
285 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
286 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
287 err |= __put_user(INSN_LDI_R20,
288 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
289 err |= __put_user(INSN_BLE_SR2_R0,
290 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
291 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
292
293#if DEBUG_SIG
294 /* Assert that we're flushing in the correct space... */
295 {
45b6eff2 296 unsigned long sid;
1da177e4
LT
297 asm ("mfsp %%sr3,%0" : "=r" (sid));
298 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
299 sid, frame->tramp);
300 }
301#endif
302
303 flush_user_dcache_range((unsigned long) &frame->tramp[0],
304 (unsigned long) &frame->tramp[TRAMP_SIZE]);
305 flush_user_icache_range((unsigned long) &frame->tramp[0],
306 (unsigned long) &frame->tramp[TRAMP_SIZE]);
307
efad798b 308 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
1da177e4
LT
309 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
310 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
311 */
312 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
313
314 if (err)
e4dc894b 315 return -EFAULT;
1da177e4 316
e4dc894b 317 haddr = A(ksig->ka.sa.sa_handler);
1da177e4 318 /* The sa_handler may be a pointer to a function descriptor */
a8f44e38 319#ifdef CONFIG_64BIT
a3ea84fa 320 if (is_compat_task()) {
1da177e4
LT
321#endif
322 if (haddr & PA_PLABEL_FDESC) {
323 Elf32_Fdesc fdesc;
324 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
325
326 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
327
328 if (err)
e4dc894b 329 return -EFAULT;
1da177e4
LT
330
331 haddr = fdesc.addr;
332 regs->gr[19] = fdesc.gp;
333 }
a8f44e38 334#ifdef CONFIG_64BIT
1da177e4
LT
335 } else {
336 Elf64_Fdesc fdesc;
337 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
338
339 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
340
341 if (err)
e4dc894b 342 return -EFAULT;
1da177e4
LT
343
344 haddr = fdesc.addr;
345 regs->gr[19] = fdesc.gp;
346 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
347 haddr, regs->gr[19], in_syscall);
348 }
349#endif
350
351 /* The syscall return path will create IAOQ values from r31.
352 */
353 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
a8f44e38 354#ifdef CONFIG_64BIT
a3ea84fa 355 if (is_compat_task())
1da177e4
LT
356 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
357#endif
358 if (in_syscall) {
359 regs->gr[31] = haddr;
a8f44e38 360#ifdef CONFIG_64BIT
df570b9c 361 if (!test_thread_flag(TIF_32BIT))
1da177e4
LT
362 sigframe_size |= 1;
363#endif
364 } else {
365 unsigned long psw = USER_PSW;
a8f44e38 366#ifdef CONFIG_64BIT
df570b9c 367 if (!test_thread_flag(TIF_32BIT))
1da177e4
LT
368 psw |= PSW_W;
369#endif
370
371 /* If we are singlestepping, arrange a trap to be delivered
372 when we return to userspace. Note the semantics -- we
373 should trap before the first insn in the handler is
374 executed. Ref:
375 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
376 */
377 if (pa_psw(current)->r) {
378 pa_psw(current)->r = 0;
379 psw |= PSW_R;
380 mtctl(-1, 0);
381 }
382
383 regs->gr[0] = psw;
384 regs->iaoq[0] = haddr | 3;
385 regs->iaoq[1] = regs->iaoq[0] + 4;
386 }
387
388 regs->gr[2] = rp; /* userland return pointer */
e4dc894b 389 regs->gr[26] = ksig->sig; /* signal number */
1da177e4 390
a8f44e38 391#ifdef CONFIG_64BIT
a3ea84fa 392 if (is_compat_task()) {
1da177e4
LT
393 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
394 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
395 } else
396#endif
397 {
398 regs->gr[25] = A(&frame->info); /* siginfo pointer */
399 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
400 }
401
402 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
403 regs->gr[30], sigframe_size,
404 regs->gr[30] + sigframe_size);
405 /* Raise the user stack pointer to make a proper call frame. */
406 regs->gr[30] = (A(frame) + sigframe_size);
407
408
409 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
410 current->comm, current->pid, frame, regs->gr[30],
411 regs->iaoq[0], regs->iaoq[1], rp);
412
1da177e4
LT
413 return 0;
414}
415
416/*
417 * OK, we're invoking a handler.
418 */
419
e3b880c6 420static void
e4dc894b 421handle_signal(struct ksignal *ksig, struct pt_regs *regs, int in_syscall)
1da177e4 422{
e4dc894b 423 int ret;
b7f9a11a 424 sigset_t *oldset = sigmask_to_save();
e4dc894b 425
1da177e4 426 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
e4dc894b 427 ksig->sig, ksig->ka, ksig->info, oldset, regs);
1da177e4
LT
428
429 /* Set up the stack frame */
e4dc894b 430 ret = setup_rt_frame(ksig, oldset, regs, in_syscall);
1da177e4 431
e4dc894b
RW
432 signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP) ||
433 test_thread_flag(TIF_BLOCKSTEP));
ecf02de5 434
a610d6e6
AV
435 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
436 regs->gr[28]);
1da177e4
LT
437}
438
2b163b71
KM
439static inline void
440syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
441{
00df111e
AV
442 if (regs->orig_r28)
443 return;
444 regs->orig_r28 = 1; /* no more restarts */
2b163b71
KM
445 /* Check the return code */
446 switch (regs->gr[28]) {
447 case -ERESTART_RESTARTBLOCK:
2b163b71
KM
448 case -ERESTARTNOHAND:
449 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
450 regs->gr[28] = -EINTR;
451 break;
452
453 case -ERESTARTSYS:
454 if (!(ka->sa.sa_flags & SA_RESTART)) {
455 DBG(1,"ERESTARTSYS: putting -EINTR\n");
456 regs->gr[28] = -EINTR;
457 break;
458 }
459 /* fallthrough */
460 case -ERESTARTNOINTR:
461 /* A syscall is just a branch, so all
462 * we have to do is fiddle the return pointer.
463 */
464 regs->gr[31] -= 8; /* delayed branching */
2b163b71
KM
465 break;
466 }
467}
468
469static inline void
470insert_restart_trampoline(struct pt_regs *regs)
471{
00df111e
AV
472 if (regs->orig_r28)
473 return;
474 regs->orig_r28 = 1; /* no more restarts */
2b163b71
KM
475 switch(regs->gr[28]) {
476 case -ERESTART_RESTARTBLOCK: {
477 /* Restart the system call - no handlers present */
478 unsigned int *usp = (unsigned int *)regs->gr[30];
0bd1e94b
HD
479 unsigned long start = (unsigned long) &usp[2];
480 unsigned long end = (unsigned long) &usp[5];
481 long err = 0;
2b163b71
KM
482
483 /* Setup a trampoline to restart the syscall
484 * with __NR_restart_syscall
485 *
486 * 0: <return address (orig r31)>
487 * 4: <2nd half for 64-bit>
488 * 8: ldw 0(%sp), %r31
489 * 12: be 0x100(%sr2, %r0)
490 * 16: ldi __NR_restart_syscall, %r20
491 */
492#ifdef CONFIG_64BIT
0bd1e94b
HD
493 err |= put_user(regs->gr[31] >> 32, &usp[0]);
494 err |= put_user(regs->gr[31] & 0xffffffff, &usp[1]);
495 err |= put_user(0x0fc010df, &usp[2]);
2b163b71 496#else
0bd1e94b
HD
497 err |= put_user(regs->gr[31], &usp[0]);
498 err |= put_user(0x0fc0109f, &usp[2]);
2b163b71 499#endif
0bd1e94b
HD
500 err |= put_user(0xe0008200, &usp[3]);
501 err |= put_user(0x34140000, &usp[4]);
2b163b71 502
0bd1e94b
HD
503 WARN_ON(err);
504
505 /* flush data/instruction cache for new insns */
506 flush_user_dcache_range(start, end);
507 flush_user_icache_range(start, end);
2b163b71
KM
508
509 regs->gr[31] = regs->gr[30] + 8;
2b163b71
KM
510 return;
511 }
512 case -ERESTARTNOHAND:
513 case -ERESTARTSYS:
514 case -ERESTARTNOINTR: {
515 /* Hooray for delayed branching. We don't
516 * have to restore %r20 (the system call
517 * number) because it gets loaded in the delay
518 * slot of the branch external instruction.
519 */
520 regs->gr[31] -= 8;
2b163b71
KM
521 return;
522 }
523 default:
524 break;
525 }
526}
527
1da177e4
LT
528/*
529 * Note that 'init' is a special process: it doesn't get signals it doesn't
530 * want to handle. Thus you cannot kill init even with a SIGKILL even by
531 * mistake.
532 *
533 * We need to be able to restore the syscall arguments (r21-r26) to
534 * restart syscalls. Thus, the syscall path should save them in the
535 * pt_regs structure (it's okay to do so since they are caller-save
536 * registers). As noted below, the syscall number gets restored for
537 * us due to the magic of delayed branching.
538 */
4650f0a5
KM
539asmlinkage void
540do_signal(struct pt_regs *regs, long in_syscall)
1da177e4 541{
e4dc894b 542 struct ksignal ksig;
1da177e4 543
b7f9a11a
AV
544 DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
545 regs, regs->sr[7], in_syscall);
1da177e4 546
e4dc894b
RW
547 if (get_signal(&ksig)) {
548 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
1da177e4 549 /* Restart a system call if necessary. */
2b163b71 550 if (in_syscall)
e4dc894b 551 syscall_restart(regs, &ksig.ka);
2b163b71 552
e4dc894b 553 handle_signal(&ksig, regs, in_syscall);
e3b880c6 554 return;
1da177e4 555 }
1da177e4
LT
556
557 /* Did we come from a system call? */
2b163b71
KM
558 if (in_syscall)
559 insert_restart_trampoline(regs);
1da177e4
LT
560
561 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
562 regs->gr[28]);
563
51a7b448 564 restore_saved_sigmask();
4650f0a5
KM
565}
566
567void do_notify_resume(struct pt_regs *regs, long in_syscall)
568{
6fd84c08 569 if (test_thread_flag(TIF_SIGPENDING))
4650f0a5 570 do_signal(regs, in_syscall);
d0420c83
DH
571
572 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
573 clear_thread_flag(TIF_NOTIFY_RESUME);
574 tracehook_notify_resume(regs);
575 }
1da177e4 576}