Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/arch/alpha/kernel/signal.c | |
3 | * | |
4 | * Copyright (C) 1995 Linus Torvalds | |
5 | * | |
6 | * 1997-11-02 Modified for POSIX.1b signals by Richard Henderson | |
7 | */ | |
8 | ||
9 | #include <linux/sched.h> | |
10 | #include <linux/kernel.h> | |
11 | #include <linux/signal.h> | |
12 | #include <linux/errno.h> | |
13 | #include <linux/wait.h> | |
14 | #include <linux/ptrace.h> | |
15 | #include <linux/unistd.h> | |
16 | #include <linux/mm.h> | |
17 | #include <linux/smp.h> | |
1da177e4 LT |
18 | #include <linux/stddef.h> |
19 | #include <linux/tty.h> | |
20 | #include <linux/binfmts.h> | |
21 | #include <linux/bitops.h> | |
e5d9a90c | 22 | #include <linux/syscalls.h> |
733e5e4b | 23 | #include <linux/tracehook.h> |
1da177e4 LT |
24 | |
25 | #include <asm/uaccess.h> | |
26 | #include <asm/sigcontext.h> | |
27 | #include <asm/ucontext.h> | |
28 | ||
29 | #include "proto.h" | |
30 | ||
31 | ||
32 | #define DEBUG_SIG 0 | |
33 | ||
34 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
35 | ||
36 | asmlinkage void ret_from_sys_call(void); | |
1da177e4 LT |
37 | |
38 | /* | |
39 | * The OSF/1 sigprocmask calling sequence is different from the | |
40 | * C sigprocmask() sequence.. | |
1da177e4 | 41 | */ |
c52c2ddc | 42 | SYSCALL_DEFINE2(osf_sigprocmask, int, how, unsigned long, newmask) |
1da177e4 | 43 | { |
c52c2ddc AV |
44 | sigset_t oldmask; |
45 | sigset_t mask; | |
46 | unsigned long res; | |
1da177e4 | 47 | |
87400e54 | 48 | siginitset(&mask, newmask & _BLOCKABLE); |
0f44fbd2 | 49 | res = sigprocmask(how, &mask, &oldmask); |
c52c2ddc AV |
50 | if (!res) { |
51 | force_successful_syscall_return(); | |
0f44fbd2 | 52 | res = oldmask.sig[0]; |
1da177e4 | 53 | } |
c52c2ddc | 54 | return res; |
1da177e4 LT |
55 | } |
56 | ||
e5d9a90c IK |
57 | SYSCALL_DEFINE3(osf_sigaction, int, sig, |
58 | const struct osf_sigaction __user *, act, | |
59 | struct osf_sigaction __user *, oact) | |
1da177e4 LT |
60 | { |
61 | struct k_sigaction new_ka, old_ka; | |
62 | int ret; | |
63 | ||
64 | if (act) { | |
65 | old_sigset_t mask; | |
66 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | |
67 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
18e6bfa9 AV |
68 | __get_user(new_ka.sa.sa_flags, &act->sa_flags) || |
69 | __get_user(mask, &act->sa_mask)) | |
1da177e4 | 70 | return -EFAULT; |
1da177e4 LT |
71 | siginitset(&new_ka.sa.sa_mask, mask); |
72 | new_ka.ka_restorer = NULL; | |
73 | } | |
74 | ||
75 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
76 | ||
77 | if (!ret && oact) { | |
78 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
79 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
18e6bfa9 AV |
80 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || |
81 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) | |
1da177e4 | 82 | return -EFAULT; |
1da177e4 LT |
83 | } |
84 | ||
85 | return ret; | |
86 | } | |
87 | ||
e5d9a90c IK |
88 | SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act, |
89 | struct sigaction __user *, oact, | |
90 | size_t, sigsetsize, void __user *, restorer) | |
1da177e4 LT |
91 | { |
92 | struct k_sigaction new_ka, old_ka; | |
93 | int ret; | |
94 | ||
95 | /* XXX: Don't preclude handling different sized sigset_t's. */ | |
96 | if (sigsetsize != sizeof(sigset_t)) | |
97 | return -EINVAL; | |
98 | ||
99 | if (act) { | |
100 | new_ka.ka_restorer = restorer; | |
101 | if (copy_from_user(&new_ka.sa, act, sizeof(*act))) | |
102 | return -EFAULT; | |
103 | } | |
104 | ||
105 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
106 | ||
107 | if (!ret && oact) { | |
108 | if (copy_to_user(oact, &old_ka.sa, sizeof(*oact))) | |
109 | return -EFAULT; | |
110 | } | |
111 | ||
112 | return ret; | |
113 | } | |
114 | ||
1da177e4 LT |
115 | /* |
116 | * Do a signal return; undo the signal stack. | |
117 | */ | |
118 | ||
119 | #if _NSIG_WORDS > 1 | |
120 | # error "Non SA_SIGINFO frame needs rearranging" | |
121 | #endif | |
122 | ||
123 | struct sigframe | |
124 | { | |
125 | struct sigcontext sc; | |
126 | unsigned int retcode[3]; | |
127 | }; | |
128 | ||
129 | struct rt_sigframe | |
130 | { | |
131 | struct siginfo info; | |
132 | struct ucontext uc; | |
133 | unsigned int retcode[3]; | |
134 | }; | |
135 | ||
136 | /* If this changes, userland unwinders that Know Things about our signal | |
137 | frame will break. Do not undertake lightly. It also implies an ABI | |
138 | change wrt the size of siginfo_t, which may cause some pain. */ | |
139 | extern char compile_time_assert | |
140 | [offsetof(struct rt_sigframe, uc.uc_mcontext) == 176 ? 1 : -1]; | |
141 | ||
142 | #define INSN_MOV_R30_R16 0x47fe0410 | |
143 | #define INSN_LDI_R0 0x201f0000 | |
144 | #define INSN_CALLSYS 0x00000083 | |
145 | ||
146 | static long | |
b960f303 | 147 | restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs) |
1da177e4 LT |
148 | { |
149 | unsigned long usp; | |
b960f303 | 150 | struct switch_stack *sw = (struct switch_stack *)regs - 1; |
1da177e4 LT |
151 | long i, err = __get_user(regs->pc, &sc->sc_pc); |
152 | ||
f56141e3 | 153 | current->restart_block.fn = do_no_restart_syscall; |
2deba1bd | 154 | |
1da177e4 LT |
155 | sw->r26 = (unsigned long) ret_from_sys_call; |
156 | ||
157 | err |= __get_user(regs->r0, sc->sc_regs+0); | |
158 | err |= __get_user(regs->r1, sc->sc_regs+1); | |
159 | err |= __get_user(regs->r2, sc->sc_regs+2); | |
160 | err |= __get_user(regs->r3, sc->sc_regs+3); | |
161 | err |= __get_user(regs->r4, sc->sc_regs+4); | |
162 | err |= __get_user(regs->r5, sc->sc_regs+5); | |
163 | err |= __get_user(regs->r6, sc->sc_regs+6); | |
164 | err |= __get_user(regs->r7, sc->sc_regs+7); | |
165 | err |= __get_user(regs->r8, sc->sc_regs+8); | |
166 | err |= __get_user(sw->r9, sc->sc_regs+9); | |
167 | err |= __get_user(sw->r10, sc->sc_regs+10); | |
168 | err |= __get_user(sw->r11, sc->sc_regs+11); | |
169 | err |= __get_user(sw->r12, sc->sc_regs+12); | |
170 | err |= __get_user(sw->r13, sc->sc_regs+13); | |
171 | err |= __get_user(sw->r14, sc->sc_regs+14); | |
172 | err |= __get_user(sw->r15, sc->sc_regs+15); | |
173 | err |= __get_user(regs->r16, sc->sc_regs+16); | |
174 | err |= __get_user(regs->r17, sc->sc_regs+17); | |
175 | err |= __get_user(regs->r18, sc->sc_regs+18); | |
176 | err |= __get_user(regs->r19, sc->sc_regs+19); | |
177 | err |= __get_user(regs->r20, sc->sc_regs+20); | |
178 | err |= __get_user(regs->r21, sc->sc_regs+21); | |
179 | err |= __get_user(regs->r22, sc->sc_regs+22); | |
180 | err |= __get_user(regs->r23, sc->sc_regs+23); | |
181 | err |= __get_user(regs->r24, sc->sc_regs+24); | |
182 | err |= __get_user(regs->r25, sc->sc_regs+25); | |
183 | err |= __get_user(regs->r26, sc->sc_regs+26); | |
184 | err |= __get_user(regs->r27, sc->sc_regs+27); | |
185 | err |= __get_user(regs->r28, sc->sc_regs+28); | |
186 | err |= __get_user(regs->gp, sc->sc_regs+29); | |
187 | err |= __get_user(usp, sc->sc_regs+30); | |
188 | wrusp(usp); | |
189 | ||
190 | for (i = 0; i < 31; i++) | |
191 | err |= __get_user(sw->fp[i], sc->sc_fpregs+i); | |
192 | err |= __get_user(sw->fp[31], &sc->sc_fpcr); | |
193 | ||
194 | return err; | |
195 | } | |
196 | ||
197 | /* Note that this syscall is also used by setcontext(3) to install | |
198 | a given sigcontext. This because it's impossible to set *all* | |
199 | registers and transfer control from userland. */ | |
200 | ||
201 | asmlinkage void | |
b960f303 | 202 | do_sigreturn(struct sigcontext __user *sc) |
1da177e4 | 203 | { |
b960f303 | 204 | struct pt_regs *regs = current_pt_regs(); |
1da177e4 LT |
205 | sigset_t set; |
206 | ||
207 | /* Verify that it's a good sigcontext before using it */ | |
208 | if (!access_ok(VERIFY_READ, sc, sizeof(*sc))) | |
209 | goto give_sigsegv; | |
210 | if (__get_user(set.sig[0], &sc->sc_mask)) | |
211 | goto give_sigsegv; | |
212 | ||
2561b069 | 213 | set_current_blocked(&set); |
1da177e4 | 214 | |
b960f303 | 215 | if (restore_sigcontext(sc, regs)) |
1da177e4 LT |
216 | goto give_sigsegv; |
217 | ||
218 | /* Send SIGTRAP if we're single-stepping: */ | |
219 | if (ptrace_cancel_bpt (current)) { | |
220 | siginfo_t info; | |
221 | ||
222 | info.si_signo = SIGTRAP; | |
223 | info.si_errno = 0; | |
224 | info.si_code = TRAP_BRKPT; | |
225 | info.si_addr = (void __user *) regs->pc; | |
226 | info.si_trapno = 0; | |
227 | send_sig_info(SIGTRAP, &info, current); | |
228 | } | |
229 | return; | |
230 | ||
231 | give_sigsegv: | |
232 | force_sig(SIGSEGV, current); | |
233 | } | |
234 | ||
235 | asmlinkage void | |
b960f303 | 236 | do_rt_sigreturn(struct rt_sigframe __user *frame) |
1da177e4 | 237 | { |
b960f303 | 238 | struct pt_regs *regs = current_pt_regs(); |
1da177e4 LT |
239 | sigset_t set; |
240 | ||
241 | /* Verify that it's a good ucontext_t before using it */ | |
242 | if (!access_ok(VERIFY_READ, &frame->uc, sizeof(frame->uc))) | |
243 | goto give_sigsegv; | |
244 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
245 | goto give_sigsegv; | |
246 | ||
2561b069 | 247 | set_current_blocked(&set); |
1da177e4 | 248 | |
b960f303 | 249 | if (restore_sigcontext(&frame->uc.uc_mcontext, regs)) |
1da177e4 LT |
250 | goto give_sigsegv; |
251 | ||
252 | /* Send SIGTRAP if we're single-stepping: */ | |
253 | if (ptrace_cancel_bpt (current)) { | |
254 | siginfo_t info; | |
255 | ||
256 | info.si_signo = SIGTRAP; | |
257 | info.si_errno = 0; | |
258 | info.si_code = TRAP_BRKPT; | |
259 | info.si_addr = (void __user *) regs->pc; | |
260 | info.si_trapno = 0; | |
261 | send_sig_info(SIGTRAP, &info, current); | |
262 | } | |
263 | return; | |
264 | ||
265 | give_sigsegv: | |
266 | force_sig(SIGSEGV, current); | |
267 | } | |
268 | ||
269 | ||
270 | /* | |
271 | * Set up a signal frame. | |
272 | */ | |
273 | ||
274 | static inline void __user * | |
cfd60c07 | 275 | get_sigframe(struct ksignal *ksig, unsigned long sp, size_t frame_size) |
1da177e4 | 276 | { |
cfd60c07 | 277 | return (void __user *)((sigsp(sp, ksig) - frame_size) & -32ul); |
1da177e4 LT |
278 | } |
279 | ||
280 | static long | |
281 | setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, | |
d9d0738a | 282 | unsigned long mask, unsigned long sp) |
1da177e4 | 283 | { |
d9d0738a | 284 | struct switch_stack *sw = (struct switch_stack *)regs - 1; |
1da177e4 LT |
285 | long i, err = 0; |
286 | ||
287 | err |= __put_user(on_sig_stack((unsigned long)sc), &sc->sc_onstack); | |
288 | err |= __put_user(mask, &sc->sc_mask); | |
289 | err |= __put_user(regs->pc, &sc->sc_pc); | |
290 | err |= __put_user(8, &sc->sc_ps); | |
291 | ||
292 | err |= __put_user(regs->r0 , sc->sc_regs+0); | |
293 | err |= __put_user(regs->r1 , sc->sc_regs+1); | |
294 | err |= __put_user(regs->r2 , sc->sc_regs+2); | |
295 | err |= __put_user(regs->r3 , sc->sc_regs+3); | |
296 | err |= __put_user(regs->r4 , sc->sc_regs+4); | |
297 | err |= __put_user(regs->r5 , sc->sc_regs+5); | |
298 | err |= __put_user(regs->r6 , sc->sc_regs+6); | |
299 | err |= __put_user(regs->r7 , sc->sc_regs+7); | |
300 | err |= __put_user(regs->r8 , sc->sc_regs+8); | |
301 | err |= __put_user(sw->r9 , sc->sc_regs+9); | |
302 | err |= __put_user(sw->r10 , sc->sc_regs+10); | |
303 | err |= __put_user(sw->r11 , sc->sc_regs+11); | |
304 | err |= __put_user(sw->r12 , sc->sc_regs+12); | |
305 | err |= __put_user(sw->r13 , sc->sc_regs+13); | |
306 | err |= __put_user(sw->r14 , sc->sc_regs+14); | |
307 | err |= __put_user(sw->r15 , sc->sc_regs+15); | |
308 | err |= __put_user(regs->r16, sc->sc_regs+16); | |
309 | err |= __put_user(regs->r17, sc->sc_regs+17); | |
310 | err |= __put_user(regs->r18, sc->sc_regs+18); | |
311 | err |= __put_user(regs->r19, sc->sc_regs+19); | |
312 | err |= __put_user(regs->r20, sc->sc_regs+20); | |
313 | err |= __put_user(regs->r21, sc->sc_regs+21); | |
314 | err |= __put_user(regs->r22, sc->sc_regs+22); | |
315 | err |= __put_user(regs->r23, sc->sc_regs+23); | |
316 | err |= __put_user(regs->r24, sc->sc_regs+24); | |
317 | err |= __put_user(regs->r25, sc->sc_regs+25); | |
318 | err |= __put_user(regs->r26, sc->sc_regs+26); | |
319 | err |= __put_user(regs->r27, sc->sc_regs+27); | |
320 | err |= __put_user(regs->r28, sc->sc_regs+28); | |
321 | err |= __put_user(regs->gp , sc->sc_regs+29); | |
322 | err |= __put_user(sp, sc->sc_regs+30); | |
323 | err |= __put_user(0, sc->sc_regs+31); | |
324 | ||
325 | for (i = 0; i < 31; i++) | |
326 | err |= __put_user(sw->fp[i], sc->sc_fpregs+i); | |
327 | err |= __put_user(0, sc->sc_fpregs+31); | |
328 | err |= __put_user(sw->fp[31], &sc->sc_fpcr); | |
329 | ||
330 | err |= __put_user(regs->trap_a0, &sc->sc_traparg_a0); | |
331 | err |= __put_user(regs->trap_a1, &sc->sc_traparg_a1); | |
332 | err |= __put_user(regs->trap_a2, &sc->sc_traparg_a2); | |
333 | ||
334 | return err; | |
335 | } | |
336 | ||
b927b3e2 | 337 | static int |
cfd60c07 | 338 | setup_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) |
1da177e4 LT |
339 | { |
340 | unsigned long oldsp, r26, err = 0; | |
341 | struct sigframe __user *frame; | |
342 | ||
343 | oldsp = rdusp(); | |
cfd60c07 | 344 | frame = get_sigframe(ksig, oldsp, sizeof(*frame)); |
1da177e4 | 345 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
cbdfb9ff | 346 | return -EFAULT; |
1da177e4 | 347 | |
d9d0738a | 348 | err |= setup_sigcontext(&frame->sc, regs, set->sig[0], oldsp); |
1da177e4 | 349 | if (err) |
cbdfb9ff | 350 | return -EFAULT; |
1da177e4 LT |
351 | |
352 | /* Set up to return from userspace. If provided, use a stub | |
353 | already in userspace. */ | |
cfd60c07 AV |
354 | r26 = (unsigned long) ksig->ka.ka_restorer; |
355 | if (!r26) { | |
1da177e4 LT |
356 | err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0); |
357 | err |= __put_user(INSN_LDI_R0+__NR_sigreturn, frame->retcode+1); | |
358 | err |= __put_user(INSN_CALLSYS, frame->retcode+2); | |
359 | imb(); | |
360 | r26 = (unsigned long) frame->retcode; | |
361 | } | |
362 | ||
363 | /* Check that everything was written properly. */ | |
364 | if (err) | |
cbdfb9ff | 365 | return err; |
1da177e4 LT |
366 | |
367 | /* "Return" to the handler */ | |
368 | regs->r26 = r26; | |
cfd60c07 AV |
369 | regs->r27 = regs->pc = (unsigned long) ksig->ka.sa.sa_handler; |
370 | regs->r16 = ksig->sig; /* a0: signal number */ | |
1da177e4 LT |
371 | regs->r17 = 0; /* a1: exception code */ |
372 | regs->r18 = (unsigned long) &frame->sc; /* a2: sigcontext pointer */ | |
373 | wrusp((unsigned long) frame); | |
374 | ||
375 | #if DEBUG_SIG | |
376 | printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", | |
377 | current->comm, current->pid, frame, regs->pc, regs->r26); | |
378 | #endif | |
b927b3e2 | 379 | return 0; |
1da177e4 LT |
380 | } |
381 | ||
b927b3e2 | 382 | static int |
cfd60c07 | 383 | setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) |
1da177e4 LT |
384 | { |
385 | unsigned long oldsp, r26, err = 0; | |
386 | struct rt_sigframe __user *frame; | |
387 | ||
388 | oldsp = rdusp(); | |
cfd60c07 | 389 | frame = get_sigframe(ksig, oldsp, sizeof(*frame)); |
1da177e4 | 390 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
cbdfb9ff | 391 | return -EFAULT; |
1da177e4 | 392 | |
cfd60c07 | 393 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); |
1da177e4 LT |
394 | |
395 | /* Create the ucontext. */ | |
396 | err |= __put_user(0, &frame->uc.uc_flags); | |
397 | err |= __put_user(0, &frame->uc.uc_link); | |
398 | err |= __put_user(set->sig[0], &frame->uc.uc_osf_sigmask); | |
50ececcf | 399 | err |= __save_altstack(&frame->uc.uc_stack, oldsp); |
d9d0738a | 400 | err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, |
1da177e4 LT |
401 | set->sig[0], oldsp); |
402 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
403 | if (err) | |
cbdfb9ff | 404 | return -EFAULT; |
1da177e4 LT |
405 | |
406 | /* Set up to return from userspace. If provided, use a stub | |
407 | already in userspace. */ | |
cfd60c07 AV |
408 | r26 = (unsigned long) ksig->ka.ka_restorer; |
409 | if (!r26) { | |
1da177e4 LT |
410 | err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0); |
411 | err |= __put_user(INSN_LDI_R0+__NR_rt_sigreturn, | |
412 | frame->retcode+1); | |
413 | err |= __put_user(INSN_CALLSYS, frame->retcode+2); | |
414 | imb(); | |
415 | r26 = (unsigned long) frame->retcode; | |
416 | } | |
417 | ||
418 | if (err) | |
cbdfb9ff | 419 | return -EFAULT; |
1da177e4 LT |
420 | |
421 | /* "Return" to the handler */ | |
422 | regs->r26 = r26; | |
cfd60c07 AV |
423 | regs->r27 = regs->pc = (unsigned long) ksig->ka.sa.sa_handler; |
424 | regs->r16 = ksig->sig; /* a0: signal number */ | |
1da177e4 LT |
425 | regs->r17 = (unsigned long) &frame->info; /* a1: siginfo pointer */ |
426 | regs->r18 = (unsigned long) &frame->uc; /* a2: ucontext pointer */ | |
427 | wrusp((unsigned long) frame); | |
428 | ||
429 | #if DEBUG_SIG | |
430 | printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", | |
431 | current->comm, current->pid, frame, regs->pc, regs->r26); | |
432 | #endif | |
433 | ||
b927b3e2 | 434 | return 0; |
1da177e4 LT |
435 | } |
436 | ||
437 | ||
438 | /* | |
439 | * OK, we're invoking a handler. | |
440 | */ | |
cbdfb9ff | 441 | static inline void |
cfd60c07 | 442 | handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
1da177e4 | 443 | { |
b7f9a11a | 444 | sigset_t *oldset = sigmask_to_save(); |
b927b3e2 RH |
445 | int ret; |
446 | ||
cfd60c07 AV |
447 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
448 | ret = setup_rt_frame(ksig, oldset, regs); | |
1da177e4 | 449 | else |
cfd60c07 | 450 | ret = setup_frame(ksig, oldset, regs); |
1da177e4 | 451 | |
cfd60c07 | 452 | signal_setup_done(ret, ksig, 0); |
1da177e4 LT |
453 | } |
454 | ||
455 | static inline void | |
456 | syscall_restart(unsigned long r0, unsigned long r19, | |
457 | struct pt_regs *regs, struct k_sigaction *ka) | |
458 | { | |
459 | switch (regs->r0) { | |
460 | case ERESTARTSYS: | |
461 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
462 | case ERESTARTNOHAND: | |
463 | regs->r0 = EINTR; | |
464 | break; | |
465 | } | |
466 | /* fallthrough */ | |
467 | case ERESTARTNOINTR: | |
468 | regs->r0 = r0; /* reset v0 and a3 and replay syscall */ | |
469 | regs->r19 = r19; | |
470 | regs->pc -= 4; | |
471 | break; | |
472 | case ERESTART_RESTARTBLOCK: | |
1da177e4 LT |
473 | regs->r0 = EINTR; |
474 | break; | |
475 | } | |
476 | } | |
477 | ||
478 | ||
479 | /* | |
480 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
481 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
482 | * mistake. | |
483 | * | |
484 | * Note that we go through the signals twice: once to check the signals that | |
485 | * the kernel can handle, and then we build all the user-level signal handling | |
486 | * stack-frames in one go after that. | |
487 | * | |
488 | * "r0" and "r19" are the registers we need to restore for system call | |
489 | * restart. "r0" is also used as an indicator whether we can restart at | |
490 | * all (if we get here from anything but a syscall return, it will be 0) | |
491 | */ | |
b927b3e2 | 492 | static void |
d9d0738a | 493 | do_signal(struct pt_regs *regs, unsigned long r0, unsigned long r19) |
1da177e4 | 494 | { |
1da177e4 | 495 | unsigned long single_stepping = ptrace_cancel_bpt(current); |
cfd60c07 | 496 | struct ksignal ksig; |
1da177e4 LT |
497 | |
498 | /* This lets the debugger run, ... */ | |
cfd60c07 AV |
499 | if (get_signal(&ksig)) { |
500 | /* ... so re-check the single stepping. */ | |
501 | single_stepping |= ptrace_cancel_bpt(current); | |
1da177e4 | 502 | /* Whee! Actually deliver the signal. */ |
b927b3e2 | 503 | if (r0) |
cfd60c07 AV |
504 | syscall_restart(r0, r19, regs, &ksig.ka); |
505 | handle_signal(&ksig, regs); | |
506 | } else { | |
507 | single_stepping |= ptrace_cancel_bpt(current); | |
508 | if (r0) { | |
509 | switch (regs->r0) { | |
510 | case ERESTARTNOHAND: | |
511 | case ERESTARTSYS: | |
512 | case ERESTARTNOINTR: | |
513 | /* Reset v0 and a3 and replay syscall. */ | |
514 | regs->r0 = r0; | |
515 | regs->r19 = r19; | |
516 | regs->pc -= 4; | |
517 | break; | |
518 | case ERESTART_RESTARTBLOCK: | |
519 | /* Set v0 to the restart_syscall and replay */ | |
520 | regs->r0 = __NR_restart_syscall; | |
521 | regs->pc -= 4; | |
522 | break; | |
523 | } | |
1da177e4 | 524 | } |
cfd60c07 | 525 | restore_saved_sigmask(); |
1da177e4 LT |
526 | } |
527 | if (single_stepping) | |
528 | ptrace_set_bpt(current); /* re-set breakpoint */ | |
1da177e4 LT |
529 | } |
530 | ||
531 | void | |
cb450766 | 532 | do_work_pending(struct pt_regs *regs, unsigned long thread_flags, |
b927b3e2 | 533 | unsigned long r0, unsigned long r19) |
1da177e4 | 534 | { |
6972d6f2 AV |
535 | do { |
536 | if (thread_flags & _TIF_NEED_RESCHED) { | |
537 | schedule(); | |
538 | } else { | |
539 | local_irq_enable(); | |
540 | if (thread_flags & _TIF_SIGPENDING) { | |
d9d0738a | 541 | do_signal(regs, r0, r19); |
6972d6f2 AV |
542 | r0 = 0; |
543 | } else { | |
544 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
545 | tracehook_notify_resume(regs); | |
546 | } | |
547 | } | |
548 | local_irq_disable(); | |
549 | thread_flags = current_thread_info()->flags; | |
550 | } while (thread_flags & _TIF_WORK_MASK); | |
1da177e4 | 551 | } |