diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/m68k/kernel/signal.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/m68k/kernel/signal.c')
-rw-r--r-- | arch/m68k/kernel/signal.c | 1025 |
1 files changed, 1025 insertions, 0 deletions
diff --git a/arch/m68k/kernel/signal.c b/arch/m68k/kernel/signal.c new file mode 100644 index 000000000000..9c636a4c238d --- /dev/null +++ b/arch/m68k/kernel/signal.c | |||
@@ -0,0 +1,1025 @@ | |||
1 | /* | ||
2 | * linux/arch/m68k/kernel/signal.c | ||
3 | * | ||
4 | * Copyright (C) 1991, 1992 Linus Torvalds | ||
5 | * | ||
6 | * This file is subject to the terms and conditions of the GNU General Public | ||
7 | * License. See the file COPYING in the main directory of this archive | ||
8 | * for more details. | ||
9 | */ | ||
10 | |||
11 | /* | ||
12 | * Linux/m68k support by Hamish Macdonald | ||
13 | * | ||
14 | * 68060 fixes by Jesper Skov | ||
15 | * | ||
16 | * 1997-12-01 Modified for POSIX.1b signals by Andreas Schwab | ||
17 | * | ||
18 | * mathemu support by Roman Zippel | ||
19 | * (Note: fpstate in the signal context is completely ignored for the emulator | ||
20 | * and the internal floating point format is put on stack) | ||
21 | */ | ||
22 | |||
23 | /* | ||
24 | * ++roman (07/09/96): implemented signal stacks (specially for tosemu on | ||
25 | * Atari :-) Current limitation: Only one sigstack can be active at one time. | ||
26 | * If a second signal with SA_ONSTACK set arrives while working on a sigstack, | ||
27 | * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested | ||
28 | * signal handlers! | ||
29 | */ | ||
30 | |||
31 | #include <linux/sched.h> | ||
32 | #include <linux/mm.h> | ||
33 | #include <linux/kernel.h> | ||
34 | #include <linux/signal.h> | ||
35 | #include <linux/syscalls.h> | ||
36 | #include <linux/errno.h> | ||
37 | #include <linux/wait.h> | ||
38 | #include <linux/ptrace.h> | ||
39 | #include <linux/unistd.h> | ||
40 | #include <linux/stddef.h> | ||
41 | #include <linux/highuid.h> | ||
42 | #include <linux/personality.h> | ||
43 | #include <linux/tty.h> | ||
44 | #include <linux/binfmts.h> | ||
45 | |||
46 | #include <asm/setup.h> | ||
47 | #include <asm/uaccess.h> | ||
48 | #include <asm/pgtable.h> | ||
49 | #include <asm/traps.h> | ||
50 | #include <asm/ucontext.h> | ||
51 | |||
52 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | ||
53 | |||
54 | asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs); | ||
55 | |||
56 | const int frame_extra_sizes[16] = { | ||
57 | [1] = -1, /* sizeof(((struct frame *)0)->un.fmt1), */ | ||
58 | [2] = sizeof(((struct frame *)0)->un.fmt2), | ||
59 | [3] = sizeof(((struct frame *)0)->un.fmt3), | ||
60 | [4] = sizeof(((struct frame *)0)->un.fmt4), | ||
61 | [5] = -1, /* sizeof(((struct frame *)0)->un.fmt5), */ | ||
62 | [6] = -1, /* sizeof(((struct frame *)0)->un.fmt6), */ | ||
63 | [7] = sizeof(((struct frame *)0)->un.fmt7), | ||
64 | [8] = -1, /* sizeof(((struct frame *)0)->un.fmt8), */ | ||
65 | [9] = sizeof(((struct frame *)0)->un.fmt9), | ||
66 | [10] = sizeof(((struct frame *)0)->un.fmta), | ||
67 | [11] = sizeof(((struct frame *)0)->un.fmtb), | ||
68 | [12] = -1, /* sizeof(((struct frame *)0)->un.fmtc), */ | ||
69 | [13] = -1, /* sizeof(((struct frame *)0)->un.fmtd), */ | ||
70 | [14] = -1, /* sizeof(((struct frame *)0)->un.fmte), */ | ||
71 | [15] = -1, /* sizeof(((struct frame *)0)->un.fmtf), */ | ||
72 | }; | ||
73 | |||
74 | /* | ||
75 | * Atomically swap in the new signal mask, and wait for a signal. | ||
76 | */ | ||
77 | asmlinkage int do_sigsuspend(struct pt_regs *regs) | ||
78 | { | ||
79 | old_sigset_t mask = regs->d3; | ||
80 | sigset_t saveset; | ||
81 | |||
82 | mask &= _BLOCKABLE; | ||
83 | saveset = current->blocked; | ||
84 | siginitset(¤t->blocked, mask); | ||
85 | recalc_sigpending(); | ||
86 | |||
87 | regs->d0 = -EINTR; | ||
88 | while (1) { | ||
89 | current->state = TASK_INTERRUPTIBLE; | ||
90 | schedule(); | ||
91 | if (do_signal(&saveset, regs)) | ||
92 | return -EINTR; | ||
93 | } | ||
94 | } | ||
95 | |||
96 | asmlinkage int | ||
97 | do_rt_sigsuspend(struct pt_regs *regs) | ||
98 | { | ||
99 | sigset_t *unewset = (sigset_t *)regs->d1; | ||
100 | size_t sigsetsize = (size_t)regs->d2; | ||
101 | sigset_t saveset, newset; | ||
102 | |||
103 | /* XXX: Don't preclude handling different sized sigset_t's. */ | ||
104 | if (sigsetsize != sizeof(sigset_t)) | ||
105 | return -EINVAL; | ||
106 | |||
107 | if (copy_from_user(&newset, unewset, sizeof(newset))) | ||
108 | return -EFAULT; | ||
109 | sigdelsetmask(&newset, ~_BLOCKABLE); | ||
110 | |||
111 | saveset = current->blocked; | ||
112 | current->blocked = newset; | ||
113 | recalc_sigpending(); | ||
114 | |||
115 | regs->d0 = -EINTR; | ||
116 | while (1) { | ||
117 | current->state = TASK_INTERRUPTIBLE; | ||
118 | schedule(); | ||
119 | if (do_signal(&saveset, regs)) | ||
120 | return -EINTR; | ||
121 | } | ||
122 | } | ||
123 | |||
124 | asmlinkage int | ||
125 | sys_sigaction(int sig, const struct old_sigaction *act, | ||
126 | struct old_sigaction *oact) | ||
127 | { | ||
128 | struct k_sigaction new_ka, old_ka; | ||
129 | int ret; | ||
130 | |||
131 | if (act) { | ||
132 | old_sigset_t mask; | ||
133 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | ||
134 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | ||
135 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | ||
136 | return -EFAULT; | ||
137 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); | ||
138 | __get_user(mask, &act->sa_mask); | ||
139 | siginitset(&new_ka.sa.sa_mask, mask); | ||
140 | } | ||
141 | |||
142 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | ||
143 | |||
144 | if (!ret && oact) { | ||
145 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | ||
146 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | ||
147 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | ||
148 | return -EFAULT; | ||
149 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); | ||
150 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | ||
151 | } | ||
152 | |||
153 | return ret; | ||
154 | } | ||
155 | |||
156 | asmlinkage int | ||
157 | sys_sigaltstack(const stack_t *uss, stack_t *uoss) | ||
158 | { | ||
159 | return do_sigaltstack(uss, uoss, rdusp()); | ||
160 | } | ||
161 | |||
162 | |||
163 | /* | ||
164 | * Do a signal return; undo the signal stack. | ||
165 | * | ||
166 | * Keep the return code on the stack quadword aligned! | ||
167 | * That makes the cache flush below easier. | ||
168 | */ | ||
169 | |||
170 | struct sigframe | ||
171 | { | ||
172 | char *pretcode; | ||
173 | int sig; | ||
174 | int code; | ||
175 | struct sigcontext *psc; | ||
176 | char retcode[8]; | ||
177 | unsigned long extramask[_NSIG_WORDS-1]; | ||
178 | struct sigcontext sc; | ||
179 | }; | ||
180 | |||
181 | struct rt_sigframe | ||
182 | { | ||
183 | char *pretcode; | ||
184 | int sig; | ||
185 | struct siginfo *pinfo; | ||
186 | void *puc; | ||
187 | char retcode[8]; | ||
188 | struct siginfo info; | ||
189 | struct ucontext uc; | ||
190 | }; | ||
191 | |||
192 | |||
193 | static unsigned char fpu_version; /* version number of fpu, set by setup_frame */ | ||
194 | |||
195 | static inline int restore_fpu_state(struct sigcontext *sc) | ||
196 | { | ||
197 | int err = 1; | ||
198 | |||
199 | if (FPU_IS_EMU) { | ||
200 | /* restore registers */ | ||
201 | memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12); | ||
202 | memcpy(current->thread.fp, sc->sc_fpregs, 24); | ||
203 | return 0; | ||
204 | } | ||
205 | |||
206 | if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { | ||
207 | /* Verify the frame format. */ | ||
208 | if (!CPU_IS_060 && (sc->sc_fpstate[0] != fpu_version)) | ||
209 | goto out; | ||
210 | if (CPU_IS_020_OR_030) { | ||
211 | if (m68k_fputype & FPU_68881 && | ||
212 | !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4)) | ||
213 | goto out; | ||
214 | if (m68k_fputype & FPU_68882 && | ||
215 | !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4)) | ||
216 | goto out; | ||
217 | } else if (CPU_IS_040) { | ||
218 | if (!(sc->sc_fpstate[1] == 0x00 || | ||
219 | sc->sc_fpstate[1] == 0x28 || | ||
220 | sc->sc_fpstate[1] == 0x60)) | ||
221 | goto out; | ||
222 | } else if (CPU_IS_060) { | ||
223 | if (!(sc->sc_fpstate[3] == 0x00 || | ||
224 | sc->sc_fpstate[3] == 0x60 || | ||
225 | sc->sc_fpstate[3] == 0xe0)) | ||
226 | goto out; | ||
227 | } else | ||
228 | goto out; | ||
229 | |||
230 | __asm__ volatile (".chip 68k/68881\n\t" | ||
231 | "fmovemx %0,%%fp0-%%fp1\n\t" | ||
232 | "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" | ||
233 | ".chip 68k" | ||
234 | : /* no outputs */ | ||
235 | : "m" (*sc->sc_fpregs), "m" (*sc->sc_fpcntl)); | ||
236 | } | ||
237 | __asm__ volatile (".chip 68k/68881\n\t" | ||
238 | "frestore %0\n\t" | ||
239 | ".chip 68k" : : "m" (*sc->sc_fpstate)); | ||
240 | err = 0; | ||
241 | |||
242 | out: | ||
243 | return err; | ||
244 | } | ||
245 | |||
246 | #define FPCONTEXT_SIZE 216 | ||
247 | #define uc_fpstate uc_filler[0] | ||
248 | #define uc_formatvec uc_filler[FPCONTEXT_SIZE/4] | ||
249 | #define uc_extra uc_filler[FPCONTEXT_SIZE/4+1] | ||
250 | |||
251 | static inline int rt_restore_fpu_state(struct ucontext *uc) | ||
252 | { | ||
253 | unsigned char fpstate[FPCONTEXT_SIZE]; | ||
254 | int context_size = CPU_IS_060 ? 8 : 0; | ||
255 | fpregset_t fpregs; | ||
256 | int err = 1; | ||
257 | |||
258 | if (FPU_IS_EMU) { | ||
259 | /* restore fpu control register */ | ||
260 | if (__copy_from_user(current->thread.fpcntl, | ||
261 | uc->uc_mcontext.fpregs.f_fpcntl, 12)) | ||
262 | goto out; | ||
263 | /* restore all other fpu register */ | ||
264 | if (__copy_from_user(current->thread.fp, | ||
265 | uc->uc_mcontext.fpregs.f_fpregs, 96)) | ||
266 | goto out; | ||
267 | return 0; | ||
268 | } | ||
269 | |||
270 | if (__get_user(*(long *)fpstate, (long *)&uc->uc_fpstate)) | ||
271 | goto out; | ||
272 | if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { | ||
273 | if (!CPU_IS_060) | ||
274 | context_size = fpstate[1]; | ||
275 | /* Verify the frame format. */ | ||
276 | if (!CPU_IS_060 && (fpstate[0] != fpu_version)) | ||
277 | goto out; | ||
278 | if (CPU_IS_020_OR_030) { | ||
279 | if (m68k_fputype & FPU_68881 && | ||
280 | !(context_size == 0x18 || context_size == 0xb4)) | ||
281 | goto out; | ||
282 | if (m68k_fputype & FPU_68882 && | ||
283 | !(context_size == 0x38 || context_size == 0xd4)) | ||
284 | goto out; | ||
285 | } else if (CPU_IS_040) { | ||
286 | if (!(context_size == 0x00 || | ||
287 | context_size == 0x28 || | ||
288 | context_size == 0x60)) | ||
289 | goto out; | ||
290 | } else if (CPU_IS_060) { | ||
291 | if (!(fpstate[3] == 0x00 || | ||
292 | fpstate[3] == 0x60 || | ||
293 | fpstate[3] == 0xe0)) | ||
294 | goto out; | ||
295 | } else | ||
296 | goto out; | ||
297 | if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs, | ||
298 | sizeof(fpregs))) | ||
299 | goto out; | ||
300 | __asm__ volatile (".chip 68k/68881\n\t" | ||
301 | "fmovemx %0,%%fp0-%%fp7\n\t" | ||
302 | "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" | ||
303 | ".chip 68k" | ||
304 | : /* no outputs */ | ||
305 | : "m" (*fpregs.f_fpregs), | ||
306 | "m" (*fpregs.f_fpcntl)); | ||
307 | } | ||
308 | if (context_size && | ||
309 | __copy_from_user(fpstate + 4, (long *)&uc->uc_fpstate + 1, | ||
310 | context_size)) | ||
311 | goto out; | ||
312 | __asm__ volatile (".chip 68k/68881\n\t" | ||
313 | "frestore %0\n\t" | ||
314 | ".chip 68k" : : "m" (*fpstate)); | ||
315 | err = 0; | ||
316 | |||
317 | out: | ||
318 | return err; | ||
319 | } | ||
320 | |||
321 | static inline int | ||
322 | restore_sigcontext(struct pt_regs *regs, struct sigcontext *usc, void *fp, | ||
323 | int *pd0) | ||
324 | { | ||
325 | int fsize, formatvec; | ||
326 | struct sigcontext context; | ||
327 | int err; | ||
328 | |||
329 | /* get previous context */ | ||
330 | if (copy_from_user(&context, usc, sizeof(context))) | ||
331 | goto badframe; | ||
332 | |||
333 | /* restore passed registers */ | ||
334 | regs->d1 = context.sc_d1; | ||
335 | regs->a0 = context.sc_a0; | ||
336 | regs->a1 = context.sc_a1; | ||
337 | regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff); | ||
338 | regs->pc = context.sc_pc; | ||
339 | regs->orig_d0 = -1; /* disable syscall checks */ | ||
340 | wrusp(context.sc_usp); | ||
341 | formatvec = context.sc_formatvec; | ||
342 | regs->format = formatvec >> 12; | ||
343 | regs->vector = formatvec & 0xfff; | ||
344 | |||
345 | err = restore_fpu_state(&context); | ||
346 | |||
347 | fsize = frame_extra_sizes[regs->format]; | ||
348 | if (fsize < 0) { | ||
349 | /* | ||
350 | * user process trying to return with weird frame format | ||
351 | */ | ||
352 | #ifdef DEBUG | ||
353 | printk("user process returning with weird frame format\n"); | ||
354 | #endif | ||
355 | goto badframe; | ||
356 | } | ||
357 | |||
358 | /* OK. Make room on the supervisor stack for the extra junk, | ||
359 | * if necessary. | ||
360 | */ | ||
361 | |||
362 | if (fsize) { | ||
363 | struct switch_stack *sw = (struct switch_stack *)regs - 1; | ||
364 | regs->d0 = context.sc_d0; | ||
365 | #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack)) | ||
366 | __asm__ __volatile__ | ||
367 | (" movel %0,%/a0\n\t" | ||
368 | " subl %1,%/a0\n\t" /* make room on stack */ | ||
369 | " movel %/a0,%/sp\n\t" /* set stack pointer */ | ||
370 | /* move switch_stack and pt_regs */ | ||
371 | "1: movel %0@+,%/a0@+\n\t" | ||
372 | " dbra %2,1b\n\t" | ||
373 | " lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */ | ||
374 | " lsrl #2,%1\n\t" | ||
375 | " subql #1,%1\n\t" | ||
376 | "2: movesl %4@+,%2\n\t" | ||
377 | "3: movel %2,%/a0@+\n\t" | ||
378 | " dbra %1,2b\n\t" | ||
379 | " bral ret_from_signal\n" | ||
380 | "4:\n" | ||
381 | ".section __ex_table,\"a\"\n" | ||
382 | " .align 4\n" | ||
383 | " .long 2b,4b\n" | ||
384 | " .long 3b,4b\n" | ||
385 | ".previous" | ||
386 | : /* no outputs, it doesn't ever return */ | ||
387 | : "a" (sw), "d" (fsize), "d" (frame_offset/4-1), | ||
388 | "n" (frame_offset), "a" (fp) | ||
389 | : "a0"); | ||
390 | #undef frame_offset | ||
391 | /* | ||
392 | * If we ever get here an exception occurred while | ||
393 | * building the above stack-frame. | ||
394 | */ | ||
395 | goto badframe; | ||
396 | } | ||
397 | |||
398 | *pd0 = context.sc_d0; | ||
399 | return err; | ||
400 | |||
401 | badframe: | ||
402 | return 1; | ||
403 | } | ||
404 | |||
405 | static inline int | ||
406 | rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw, | ||
407 | struct ucontext *uc, int *pd0) | ||
408 | { | ||
409 | int fsize, temp; | ||
410 | greg_t *gregs = uc->uc_mcontext.gregs; | ||
411 | unsigned long usp; | ||
412 | int err; | ||
413 | |||
414 | err = __get_user(temp, &uc->uc_mcontext.version); | ||
415 | if (temp != MCONTEXT_VERSION) | ||
416 | goto badframe; | ||
417 | /* restore passed registers */ | ||
418 | err |= __get_user(regs->d0, &gregs[0]); | ||
419 | err |= __get_user(regs->d1, &gregs[1]); | ||
420 | err |= __get_user(regs->d2, &gregs[2]); | ||
421 | err |= __get_user(regs->d3, &gregs[3]); | ||
422 | err |= __get_user(regs->d4, &gregs[4]); | ||
423 | err |= __get_user(regs->d5, &gregs[5]); | ||
424 | err |= __get_user(sw->d6, &gregs[6]); | ||
425 | err |= __get_user(sw->d7, &gregs[7]); | ||
426 | err |= __get_user(regs->a0, &gregs[8]); | ||
427 | err |= __get_user(regs->a1, &gregs[9]); | ||
428 | err |= __get_user(regs->a2, &gregs[10]); | ||
429 | err |= __get_user(sw->a3, &gregs[11]); | ||
430 | err |= __get_user(sw->a4, &gregs[12]); | ||
431 | err |= __get_user(sw->a5, &gregs[13]); | ||
432 | err |= __get_user(sw->a6, &gregs[14]); | ||
433 | err |= __get_user(usp, &gregs[15]); | ||
434 | wrusp(usp); | ||
435 | err |= __get_user(regs->pc, &gregs[16]); | ||
436 | err |= __get_user(temp, &gregs[17]); | ||
437 | regs->sr = (regs->sr & 0xff00) | (temp & 0xff); | ||
438 | regs->orig_d0 = -1; /* disable syscall checks */ | ||
439 | err |= __get_user(temp, &uc->uc_formatvec); | ||
440 | regs->format = temp >> 12; | ||
441 | regs->vector = temp & 0xfff; | ||
442 | |||
443 | err |= rt_restore_fpu_state(uc); | ||
444 | |||
445 | if (do_sigaltstack(&uc->uc_stack, NULL, usp) == -EFAULT) | ||
446 | goto badframe; | ||
447 | |||
448 | fsize = frame_extra_sizes[regs->format]; | ||
449 | if (fsize < 0) { | ||
450 | /* | ||
451 | * user process trying to return with weird frame format | ||
452 | */ | ||
453 | #ifdef DEBUG | ||
454 | printk("user process returning with weird frame format\n"); | ||
455 | #endif | ||
456 | goto badframe; | ||
457 | } | ||
458 | |||
459 | /* OK. Make room on the supervisor stack for the extra junk, | ||
460 | * if necessary. | ||
461 | */ | ||
462 | |||
463 | if (fsize) { | ||
464 | #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack)) | ||
465 | __asm__ __volatile__ | ||
466 | (" movel %0,%/a0\n\t" | ||
467 | " subl %1,%/a0\n\t" /* make room on stack */ | ||
468 | " movel %/a0,%/sp\n\t" /* set stack pointer */ | ||
469 | /* move switch_stack and pt_regs */ | ||
470 | "1: movel %0@+,%/a0@+\n\t" | ||
471 | " dbra %2,1b\n\t" | ||
472 | " lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */ | ||
473 | " lsrl #2,%1\n\t" | ||
474 | " subql #1,%1\n\t" | ||
475 | "2: movesl %4@+,%2\n\t" | ||
476 | "3: movel %2,%/a0@+\n\t" | ||
477 | " dbra %1,2b\n\t" | ||
478 | " bral ret_from_signal\n" | ||
479 | "4:\n" | ||
480 | ".section __ex_table,\"a\"\n" | ||
481 | " .align 4\n" | ||
482 | " .long 2b,4b\n" | ||
483 | " .long 3b,4b\n" | ||
484 | ".previous" | ||
485 | : /* no outputs, it doesn't ever return */ | ||
486 | : "a" (sw), "d" (fsize), "d" (frame_offset/4-1), | ||
487 | "n" (frame_offset), "a" (&uc->uc_extra) | ||
488 | : "a0"); | ||
489 | #undef frame_offset | ||
490 | /* | ||
491 | * If we ever get here an exception occurred while | ||
492 | * building the above stack-frame. | ||
493 | */ | ||
494 | goto badframe; | ||
495 | } | ||
496 | |||
497 | *pd0 = regs->d0; | ||
498 | return err; | ||
499 | |||
500 | badframe: | ||
501 | return 1; | ||
502 | } | ||
503 | |||
504 | asmlinkage int do_sigreturn(unsigned long __unused) | ||
505 | { | ||
506 | struct switch_stack *sw = (struct switch_stack *) &__unused; | ||
507 | struct pt_regs *regs = (struct pt_regs *) (sw + 1); | ||
508 | unsigned long usp = rdusp(); | ||
509 | struct sigframe *frame = (struct sigframe *)(usp - 4); | ||
510 | sigset_t set; | ||
511 | int d0; | ||
512 | |||
513 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | ||
514 | goto badframe; | ||
515 | if (__get_user(set.sig[0], &frame->sc.sc_mask) || | ||
516 | (_NSIG_WORDS > 1 && | ||
517 | __copy_from_user(&set.sig[1], &frame->extramask, | ||
518 | sizeof(frame->extramask)))) | ||
519 | goto badframe; | ||
520 | |||
521 | sigdelsetmask(&set, ~_BLOCKABLE); | ||
522 | current->blocked = set; | ||
523 | recalc_sigpending(); | ||
524 | |||
525 | if (restore_sigcontext(regs, &frame->sc, frame + 1, &d0)) | ||
526 | goto badframe; | ||
527 | return d0; | ||
528 | |||
529 | badframe: | ||
530 | force_sig(SIGSEGV, current); | ||
531 | return 0; | ||
532 | } | ||
533 | |||
534 | asmlinkage int do_rt_sigreturn(unsigned long __unused) | ||
535 | { | ||
536 | struct switch_stack *sw = (struct switch_stack *) &__unused; | ||
537 | struct pt_regs *regs = (struct pt_regs *) (sw + 1); | ||
538 | unsigned long usp = rdusp(); | ||
539 | struct rt_sigframe *frame = (struct rt_sigframe *)(usp - 4); | ||
540 | sigset_t set; | ||
541 | int d0; | ||
542 | |||
543 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | ||
544 | goto badframe; | ||
545 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | ||
546 | goto badframe; | ||
547 | |||
548 | sigdelsetmask(&set, ~_BLOCKABLE); | ||
549 | current->blocked = set; | ||
550 | recalc_sigpending(); | ||
551 | |||
552 | if (rt_restore_ucontext(regs, sw, &frame->uc, &d0)) | ||
553 | goto badframe; | ||
554 | return d0; | ||
555 | |||
556 | badframe: | ||
557 | force_sig(SIGSEGV, current); | ||
558 | return 0; | ||
559 | } | ||
560 | |||
561 | /* | ||
562 | * Set up a signal frame. | ||
563 | */ | ||
564 | |||
565 | static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) | ||
566 | { | ||
567 | if (FPU_IS_EMU) { | ||
568 | /* save registers */ | ||
569 | memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12); | ||
570 | memcpy(sc->sc_fpregs, current->thread.fp, 24); | ||
571 | return; | ||
572 | } | ||
573 | |||
574 | __asm__ volatile (".chip 68k/68881\n\t" | ||
575 | "fsave %0\n\t" | ||
576 | ".chip 68k" | ||
577 | : : "m" (*sc->sc_fpstate) : "memory"); | ||
578 | |||
579 | if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { | ||
580 | fpu_version = sc->sc_fpstate[0]; | ||
581 | if (CPU_IS_020_OR_030 && | ||
582 | regs->vector >= (VEC_FPBRUC * 4) && | ||
583 | regs->vector <= (VEC_FPNAN * 4)) { | ||
584 | /* Clear pending exception in 68882 idle frame */ | ||
585 | if (*(unsigned short *) sc->sc_fpstate == 0x1f38) | ||
586 | sc->sc_fpstate[0x38] |= 1 << 3; | ||
587 | } | ||
588 | __asm__ volatile (".chip 68k/68881\n\t" | ||
589 | "fmovemx %%fp0-%%fp1,%0\n\t" | ||
590 | "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" | ||
591 | ".chip 68k" | ||
592 | : "=m" (*sc->sc_fpregs), | ||
593 | "=m" (*sc->sc_fpcntl) | ||
594 | : /* no inputs */ | ||
595 | : "memory"); | ||
596 | } | ||
597 | } | ||
598 | |||
599 | static inline int rt_save_fpu_state(struct ucontext *uc, struct pt_regs *regs) | ||
600 | { | ||
601 | unsigned char fpstate[FPCONTEXT_SIZE]; | ||
602 | int context_size = CPU_IS_060 ? 8 : 0; | ||
603 | int err = 0; | ||
604 | |||
605 | if (FPU_IS_EMU) { | ||
606 | /* save fpu control register */ | ||
607 | err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl, | ||
608 | current->thread.fpcntl, 12); | ||
609 | /* save all other fpu register */ | ||
610 | err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs, | ||
611 | current->thread.fp, 96); | ||
612 | return err; | ||
613 | } | ||
614 | |||
615 | __asm__ volatile (".chip 68k/68881\n\t" | ||
616 | "fsave %0\n\t" | ||
617 | ".chip 68k" | ||
618 | : : "m" (*fpstate) : "memory"); | ||
619 | |||
620 | err |= __put_user(*(long *)fpstate, (long *)&uc->uc_fpstate); | ||
621 | if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { | ||
622 | fpregset_t fpregs; | ||
623 | if (!CPU_IS_060) | ||
624 | context_size = fpstate[1]; | ||
625 | fpu_version = fpstate[0]; | ||
626 | if (CPU_IS_020_OR_030 && | ||
627 | regs->vector >= (VEC_FPBRUC * 4) && | ||
628 | regs->vector <= (VEC_FPNAN * 4)) { | ||
629 | /* Clear pending exception in 68882 idle frame */ | ||
630 | if (*(unsigned short *) fpstate == 0x1f38) | ||
631 | fpstate[0x38] |= 1 << 3; | ||
632 | } | ||
633 | __asm__ volatile (".chip 68k/68881\n\t" | ||
634 | "fmovemx %%fp0-%%fp7,%0\n\t" | ||
635 | "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" | ||
636 | ".chip 68k" | ||
637 | : "=m" (*fpregs.f_fpregs), | ||
638 | "=m" (*fpregs.f_fpcntl) | ||
639 | : /* no inputs */ | ||
640 | : "memory"); | ||
641 | err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs, | ||
642 | sizeof(fpregs)); | ||
643 | } | ||
644 | if (context_size) | ||
645 | err |= copy_to_user((long *)&uc->uc_fpstate + 1, fpstate + 4, | ||
646 | context_size); | ||
647 | return err; | ||
648 | } | ||
649 | |||
650 | static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, | ||
651 | unsigned long mask) | ||
652 | { | ||
653 | sc->sc_mask = mask; | ||
654 | sc->sc_usp = rdusp(); | ||
655 | sc->sc_d0 = regs->d0; | ||
656 | sc->sc_d1 = regs->d1; | ||
657 | sc->sc_a0 = regs->a0; | ||
658 | sc->sc_a1 = regs->a1; | ||
659 | sc->sc_sr = regs->sr; | ||
660 | sc->sc_pc = regs->pc; | ||
661 | sc->sc_formatvec = regs->format << 12 | regs->vector; | ||
662 | save_fpu_state(sc, regs); | ||
663 | } | ||
664 | |||
665 | static inline int rt_setup_ucontext(struct ucontext *uc, struct pt_regs *regs) | ||
666 | { | ||
667 | struct switch_stack *sw = (struct switch_stack *)regs - 1; | ||
668 | greg_t *gregs = uc->uc_mcontext.gregs; | ||
669 | int err = 0; | ||
670 | |||
671 | err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); | ||
672 | err |= __put_user(regs->d0, &gregs[0]); | ||
673 | err |= __put_user(regs->d1, &gregs[1]); | ||
674 | err |= __put_user(regs->d2, &gregs[2]); | ||
675 | err |= __put_user(regs->d3, &gregs[3]); | ||
676 | err |= __put_user(regs->d4, &gregs[4]); | ||
677 | err |= __put_user(regs->d5, &gregs[5]); | ||
678 | err |= __put_user(sw->d6, &gregs[6]); | ||
679 | err |= __put_user(sw->d7, &gregs[7]); | ||
680 | err |= __put_user(regs->a0, &gregs[8]); | ||
681 | err |= __put_user(regs->a1, &gregs[9]); | ||
682 | err |= __put_user(regs->a2, &gregs[10]); | ||
683 | err |= __put_user(sw->a3, &gregs[11]); | ||
684 | err |= __put_user(sw->a4, &gregs[12]); | ||
685 | err |= __put_user(sw->a5, &gregs[13]); | ||
686 | err |= __put_user(sw->a6, &gregs[14]); | ||
687 | err |= __put_user(rdusp(), &gregs[15]); | ||
688 | err |= __put_user(regs->pc, &gregs[16]); | ||
689 | err |= __put_user(regs->sr, &gregs[17]); | ||
690 | err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec); | ||
691 | err |= rt_save_fpu_state(uc, regs); | ||
692 | return err; | ||
693 | } | ||
694 | |||
695 | static inline void push_cache (unsigned long vaddr) | ||
696 | { | ||
697 | /* | ||
698 | * Using the old cache_push_v() was really a big waste. | ||
699 | * | ||
700 | * What we are trying to do is to flush 8 bytes to ram. | ||
701 | * Flushing 2 cache lines of 16 bytes is much cheaper than | ||
702 | * flushing 1 or 2 pages, as previously done in | ||
703 | * cache_push_v(). | ||
704 | * Jes | ||
705 | */ | ||
706 | if (CPU_IS_040) { | ||
707 | unsigned long temp; | ||
708 | |||
709 | __asm__ __volatile__ (".chip 68040\n\t" | ||
710 | "nop\n\t" | ||
711 | "ptestr (%1)\n\t" | ||
712 | "movec %%mmusr,%0\n\t" | ||
713 | ".chip 68k" | ||
714 | : "=r" (temp) | ||
715 | : "a" (vaddr)); | ||
716 | |||
717 | temp &= PAGE_MASK; | ||
718 | temp |= vaddr & ~PAGE_MASK; | ||
719 | |||
720 | __asm__ __volatile__ (".chip 68040\n\t" | ||
721 | "nop\n\t" | ||
722 | "cpushl %%bc,(%0)\n\t" | ||
723 | ".chip 68k" | ||
724 | : : "a" (temp)); | ||
725 | } | ||
726 | else if (CPU_IS_060) { | ||
727 | unsigned long temp; | ||
728 | __asm__ __volatile__ (".chip 68060\n\t" | ||
729 | "plpar (%0)\n\t" | ||
730 | ".chip 68k" | ||
731 | : "=a" (temp) | ||
732 | : "0" (vaddr)); | ||
733 | __asm__ __volatile__ (".chip 68060\n\t" | ||
734 | "cpushl %%bc,(%0)\n\t" | ||
735 | ".chip 68k" | ||
736 | : : "a" (temp)); | ||
737 | } | ||
738 | else { | ||
739 | /* | ||
740 | * 68030/68020 have no writeback cache; | ||
741 | * still need to clear icache. | ||
742 | * Note that vaddr is guaranteed to be long word aligned. | ||
743 | */ | ||
744 | unsigned long temp; | ||
745 | asm volatile ("movec %%cacr,%0" : "=r" (temp)); | ||
746 | temp += 4; | ||
747 | asm volatile ("movec %0,%%caar\n\t" | ||
748 | "movec %1,%%cacr" | ||
749 | : : "r" (vaddr), "r" (temp)); | ||
750 | asm volatile ("movec %0,%%caar\n\t" | ||
751 | "movec %1,%%cacr" | ||
752 | : : "r" (vaddr + 4), "r" (temp)); | ||
753 | } | ||
754 | } | ||
755 | |||
756 | static inline void * | ||
757 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size) | ||
758 | { | ||
759 | unsigned long usp; | ||
760 | |||
761 | /* Default to using normal stack. */ | ||
762 | usp = rdusp(); | ||
763 | |||
764 | /* This is the X/Open sanctioned signal stack switching. */ | ||
765 | if (ka->sa.sa_flags & SA_ONSTACK) { | ||
766 | if (!on_sig_stack(usp)) | ||
767 | usp = current->sas_ss_sp + current->sas_ss_size; | ||
768 | } | ||
769 | return (void *)((usp - frame_size) & -8UL); | ||
770 | } | ||
771 | |||
772 | static void setup_frame (int sig, struct k_sigaction *ka, | ||
773 | sigset_t *set, struct pt_regs *regs) | ||
774 | { | ||
775 | struct sigframe *frame; | ||
776 | int fsize = frame_extra_sizes[regs->format]; | ||
777 | struct sigcontext context; | ||
778 | int err = 0; | ||
779 | |||
780 | if (fsize < 0) { | ||
781 | #ifdef DEBUG | ||
782 | printk ("setup_frame: Unknown frame format %#x\n", | ||
783 | regs->format); | ||
784 | #endif | ||
785 | goto give_sigsegv; | ||
786 | } | ||
787 | |||
788 | frame = get_sigframe(ka, regs, sizeof(*frame) + fsize); | ||
789 | |||
790 | if (fsize) { | ||
791 | err |= copy_to_user (frame + 1, regs + 1, fsize); | ||
792 | regs->stkadj = fsize; | ||
793 | } | ||
794 | |||
795 | err |= __put_user((current_thread_info()->exec_domain | ||
796 | && current_thread_info()->exec_domain->signal_invmap | ||
797 | && sig < 32 | ||
798 | ? current_thread_info()->exec_domain->signal_invmap[sig] | ||
799 | : sig), | ||
800 | &frame->sig); | ||
801 | |||
802 | err |= __put_user(regs->vector, &frame->code); | ||
803 | err |= __put_user(&frame->sc, &frame->psc); | ||
804 | |||
805 | if (_NSIG_WORDS > 1) | ||
806 | err |= copy_to_user(frame->extramask, &set->sig[1], | ||
807 | sizeof(frame->extramask)); | ||
808 | |||
809 | setup_sigcontext(&context, regs, set->sig[0]); | ||
810 | err |= copy_to_user (&frame->sc, &context, sizeof(context)); | ||
811 | |||
812 | /* Set up to return from userspace. */ | ||
813 | err |= __put_user(frame->retcode, &frame->pretcode); | ||
814 | /* moveq #,d0; trap #0 */ | ||
815 | err |= __put_user(0x70004e40 + (__NR_sigreturn << 16), | ||
816 | (long *)(frame->retcode)); | ||
817 | |||
818 | if (err) | ||
819 | goto give_sigsegv; | ||
820 | |||
821 | push_cache ((unsigned long) &frame->retcode); | ||
822 | |||
823 | /* Set up registers for signal handler */ | ||
824 | wrusp ((unsigned long) frame); | ||
825 | regs->pc = (unsigned long) ka->sa.sa_handler; | ||
826 | |||
827 | adjust_stack: | ||
828 | /* Prepare to skip over the extra stuff in the exception frame. */ | ||
829 | if (regs->stkadj) { | ||
830 | struct pt_regs *tregs = | ||
831 | (struct pt_regs *)((ulong)regs + regs->stkadj); | ||
832 | #ifdef DEBUG | ||
833 | printk("Performing stackadjust=%04x\n", regs->stkadj); | ||
834 | #endif | ||
835 | /* This must be copied with decreasing addresses to | ||
836 | handle overlaps. */ | ||
837 | tregs->vector = 0; | ||
838 | tregs->format = 0; | ||
839 | tregs->pc = regs->pc; | ||
840 | tregs->sr = regs->sr; | ||
841 | } | ||
842 | return; | ||
843 | |||
844 | give_sigsegv: | ||
845 | force_sigsegv(sig, current); | ||
846 | goto adjust_stack; | ||
847 | } | ||
848 | |||
849 | static void setup_rt_frame (int sig, struct k_sigaction *ka, siginfo_t *info, | ||
850 | sigset_t *set, struct pt_regs *regs) | ||
851 | { | ||
852 | struct rt_sigframe *frame; | ||
853 | int fsize = frame_extra_sizes[regs->format]; | ||
854 | int err = 0; | ||
855 | |||
856 | if (fsize < 0) { | ||
857 | #ifdef DEBUG | ||
858 | printk ("setup_frame: Unknown frame format %#x\n", | ||
859 | regs->format); | ||
860 | #endif | ||
861 | goto give_sigsegv; | ||
862 | } | ||
863 | |||
864 | frame = get_sigframe(ka, regs, sizeof(*frame)); | ||
865 | |||
866 | if (fsize) { | ||
867 | err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize); | ||
868 | regs->stkadj = fsize; | ||
869 | } | ||
870 | |||
871 | err |= __put_user((current_thread_info()->exec_domain | ||
872 | && current_thread_info()->exec_domain->signal_invmap | ||
873 | && sig < 32 | ||
874 | ? current_thread_info()->exec_domain->signal_invmap[sig] | ||
875 | : sig), | ||
876 | &frame->sig); | ||
877 | err |= __put_user(&frame->info, &frame->pinfo); | ||
878 | err |= __put_user(&frame->uc, &frame->puc); | ||
879 | err |= copy_siginfo_to_user(&frame->info, info); | ||
880 | |||
881 | /* Create the ucontext. */ | ||
882 | err |= __put_user(0, &frame->uc.uc_flags); | ||
883 | err |= __put_user(0, &frame->uc.uc_link); | ||
884 | err |= __put_user((void *)current->sas_ss_sp, | ||
885 | &frame->uc.uc_stack.ss_sp); | ||
886 | err |= __put_user(sas_ss_flags(rdusp()), | ||
887 | &frame->uc.uc_stack.ss_flags); | ||
888 | err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | ||
889 | err |= rt_setup_ucontext(&frame->uc, regs); | ||
890 | err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); | ||
891 | |||
892 | /* Set up to return from userspace. */ | ||
893 | err |= __put_user(frame->retcode, &frame->pretcode); | ||
894 | /* moveq #,d0; notb d0; trap #0 */ | ||
895 | err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16), | ||
896 | (long *)(frame->retcode + 0)); | ||
897 | err |= __put_user(0x4e40, (short *)(frame->retcode + 4)); | ||
898 | |||
899 | if (err) | ||
900 | goto give_sigsegv; | ||
901 | |||
902 | push_cache ((unsigned long) &frame->retcode); | ||
903 | |||
904 | /* Set up registers for signal handler */ | ||
905 | wrusp ((unsigned long) frame); | ||
906 | regs->pc = (unsigned long) ka->sa.sa_handler; | ||
907 | |||
908 | adjust_stack: | ||
909 | /* Prepare to skip over the extra stuff in the exception frame. */ | ||
910 | if (regs->stkadj) { | ||
911 | struct pt_regs *tregs = | ||
912 | (struct pt_regs *)((ulong)regs + regs->stkadj); | ||
913 | #ifdef DEBUG | ||
914 | printk("Performing stackadjust=%04x\n", regs->stkadj); | ||
915 | #endif | ||
916 | /* This must be copied with decreasing addresses to | ||
917 | handle overlaps. */ | ||
918 | tregs->vector = 0; | ||
919 | tregs->format = 0; | ||
920 | tregs->pc = regs->pc; | ||
921 | tregs->sr = regs->sr; | ||
922 | } | ||
923 | return; | ||
924 | |||
925 | give_sigsegv: | ||
926 | force_sigsegv(sig, current); | ||
927 | goto adjust_stack; | ||
928 | } | ||
929 | |||
930 | static inline void | ||
931 | handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler) | ||
932 | { | ||
933 | switch (regs->d0) { | ||
934 | case -ERESTARTNOHAND: | ||
935 | if (!has_handler) | ||
936 | goto do_restart; | ||
937 | regs->d0 = -EINTR; | ||
938 | break; | ||
939 | |||
940 | case -ERESTARTSYS: | ||
941 | if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { | ||
942 | regs->d0 = -EINTR; | ||
943 | break; | ||
944 | } | ||
945 | /* fallthrough */ | ||
946 | case -ERESTARTNOINTR: | ||
947 | do_restart: | ||
948 | regs->d0 = regs->orig_d0; | ||
949 | regs->pc -= 2; | ||
950 | break; | ||
951 | } | ||
952 | } | ||
953 | |||
954 | void ptrace_signal_deliver(struct pt_regs *regs, void *cookie) | ||
955 | { | ||
956 | if (regs->orig_d0 < 0) | ||
957 | return; | ||
958 | switch (regs->d0) { | ||
959 | case -ERESTARTNOHAND: | ||
960 | case -ERESTARTSYS: | ||
961 | case -ERESTARTNOINTR: | ||
962 | regs->d0 = regs->orig_d0; | ||
963 | regs->orig_d0 = -1; | ||
964 | regs->pc -= 2; | ||
965 | break; | ||
966 | } | ||
967 | } | ||
968 | |||
969 | /* | ||
970 | * OK, we're invoking a handler | ||
971 | */ | ||
972 | static void | ||
973 | handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info, | ||
974 | sigset_t *oldset, struct pt_regs *regs) | ||
975 | { | ||
976 | /* are we from a system call? */ | ||
977 | if (regs->orig_d0 >= 0) | ||
978 | /* If so, check system call restarting.. */ | ||
979 | handle_restart(regs, ka, 1); | ||
980 | |||
981 | /* set up the stack frame */ | ||
982 | if (ka->sa.sa_flags & SA_SIGINFO) | ||
983 | setup_rt_frame(sig, ka, info, oldset, regs); | ||
984 | else | ||
985 | setup_frame(sig, ka, oldset, regs); | ||
986 | |||
987 | if (ka->sa.sa_flags & SA_ONESHOT) | ||
988 | ka->sa.sa_handler = SIG_DFL; | ||
989 | |||
990 | sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); | ||
991 | if (!(ka->sa.sa_flags & SA_NODEFER)) | ||
992 | sigaddset(¤t->blocked,sig); | ||
993 | recalc_sigpending(); | ||
994 | } | ||
995 | |||
996 | /* | ||
997 | * Note that 'init' is a special process: it doesn't get signals it doesn't | ||
998 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | ||
999 | * mistake. | ||
1000 | */ | ||
1001 | asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs) | ||
1002 | { | ||
1003 | siginfo_t info; | ||
1004 | struct k_sigaction ka; | ||
1005 | int signr; | ||
1006 | |||
1007 | current->thread.esp0 = (unsigned long) regs; | ||
1008 | |||
1009 | if (!oldset) | ||
1010 | oldset = ¤t->blocked; | ||
1011 | |||
1012 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | ||
1013 | if (signr > 0) { | ||
1014 | /* Whee! Actually deliver the signal. */ | ||
1015 | handle_signal(signr, &ka, &info, oldset, regs); | ||
1016 | return 1; | ||
1017 | } | ||
1018 | |||
1019 | /* Did we come from a system call? */ | ||
1020 | if (regs->orig_d0 >= 0) | ||
1021 | /* Restart the system call - no handlers present */ | ||
1022 | handle_restart(regs, NULL, 0); | ||
1023 | |||
1024 | return 0; | ||
1025 | } | ||