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-rw-r--r--arch/ppc64/kernel/signal.c581
1 files changed, 0 insertions, 581 deletions
diff --git a/arch/ppc64/kernel/signal.c b/arch/ppc64/kernel/signal.c
deleted file mode 100644
index ec9d0984b6a0..000000000000
--- a/arch/ppc64/kernel/signal.c
+++ /dev/null
@@ -1,581 +0,0 @@
1/*
2 * linux/arch/ppc64/kernel/signal.c
3 *
4 * PowerPC version
5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 *
7 * Derived from "arch/i386/kernel/signal.c"
8 * Copyright (C) 1991, 1992 Linus Torvalds
9 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 */
16
17#include <linux/config.h>
18#include <linux/sched.h>
19#include <linux/mm.h>
20#include <linux/smp.h>
21#include <linux/smp_lock.h>
22#include <linux/kernel.h>
23#include <linux/signal.h>
24#include <linux/errno.h>
25#include <linux/wait.h>
26#include <linux/unistd.h>
27#include <linux/stddef.h>
28#include <linux/elf.h>
29#include <linux/ptrace.h>
30#include <linux/module.h>
31
32#include <asm/sigcontext.h>
33#include <asm/ucontext.h>
34#include <asm/uaccess.h>
35#include <asm/pgtable.h>
36#include <asm/ppcdebug.h>
37#include <asm/unistd.h>
38#include <asm/cacheflush.h>
39#include <asm/vdso.h>
40
41#define DEBUG_SIG 0
42
43#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
44
45#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
46#define FP_REGS_SIZE sizeof(elf_fpregset_t)
47
48#define TRAMP_TRACEBACK 3
49#define TRAMP_SIZE 6
50
51/*
52 * When we have signals to deliver, we set up on the user stack,
53 * going down from the original stack pointer:
54 * 1) a rt_sigframe struct which contains the ucontext
55 * 2) a gap of __SIGNAL_FRAMESIZE bytes which acts as a dummy caller
56 * frame for the signal handler.
57 */
58
59struct rt_sigframe {
60 /* sys_rt_sigreturn requires the ucontext be the first field */
61 struct ucontext uc;
62 unsigned long _unused[2];
63 unsigned int tramp[TRAMP_SIZE];
64 struct siginfo *pinfo;
65 void *puc;
66 struct siginfo info;
67 /* 64 bit ABI allows for 288 bytes below sp before decrementing it. */
68 char abigap[288];
69} __attribute__ ((aligned (16)));
70
71
72/*
73 * Atomically swap in the new signal mask, and wait for a signal.
74 */
75long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, int p3, int p4,
76 int p6, int p7, struct pt_regs *regs)
77{
78 sigset_t saveset, newset;
79
80 /* XXX: Don't preclude handling different sized sigset_t's. */
81 if (sigsetsize != sizeof(sigset_t))
82 return -EINVAL;
83
84 if (copy_from_user(&newset, unewset, sizeof(newset)))
85 return -EFAULT;
86 sigdelsetmask(&newset, ~_BLOCKABLE);
87
88 spin_lock_irq(&current->sighand->siglock);
89 saveset = current->blocked;
90 current->blocked = newset;
91 recalc_sigpending();
92 spin_unlock_irq(&current->sighand->siglock);
93
94 regs->result = -EINTR;
95 regs->gpr[3] = EINTR;
96 regs->ccr |= 0x10000000;
97 while (1) {
98 current->state = TASK_INTERRUPTIBLE;
99 schedule();
100 if (do_signal(&saveset, regs))
101 return 0;
102 }
103}
104
105long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, unsigned long r5,
106 unsigned long r6, unsigned long r7, unsigned long r8,
107 struct pt_regs *regs)
108{
109 return do_sigaltstack(uss, uoss, regs->gpr[1]);
110}
111
112
113/*
114 * Set up the sigcontext for the signal frame.
115 */
116
117static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
118 int signr, sigset_t *set, unsigned long handler)
119{
120 /* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
121 * process never used altivec yet (MSR_VEC is zero in pt_regs of
122 * the context). This is very important because we must ensure we
123 * don't lose the VRSAVE content that may have been set prior to
124 * the process doing its first vector operation
125 * Userland shall check AT_HWCAP to know wether it can rely on the
126 * v_regs pointer or not
127 */
128#ifdef CONFIG_ALTIVEC
129 elf_vrreg_t __user *v_regs = (elf_vrreg_t __user *)(((unsigned long)sc->vmx_reserve + 15) & ~0xful);
130#endif
131 long err = 0;
132
133 flush_fp_to_thread(current);
134
135 /* Make sure signal doesn't get spurrious FP exceptions */
136 current->thread.fpscr.val = 0;
137
138#ifdef CONFIG_ALTIVEC
139 err |= __put_user(v_regs, &sc->v_regs);
140
141 /* save altivec registers */
142 if (current->thread.used_vr) {
143 flush_altivec_to_thread(current);
144 /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
145 err |= __copy_to_user(v_regs, current->thread.vr, 33 * sizeof(vector128));
146 /* set MSR_VEC in the MSR value in the frame to indicate that sc->v_reg)
147 * contains valid data.
148 */
149 regs->msr |= MSR_VEC;
150 }
151 /* We always copy to/from vrsave, it's 0 if we don't have or don't
152 * use altivec.
153 */
154 err |= __put_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
155#else /* CONFIG_ALTIVEC */
156 err |= __put_user(0, &sc->v_regs);
157#endif /* CONFIG_ALTIVEC */
158 err |= __put_user(&sc->gp_regs, &sc->regs);
159 err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE);
160 err |= __copy_to_user(&sc->fp_regs, &current->thread.fpr, FP_REGS_SIZE);
161 err |= __put_user(signr, &sc->signal);
162 err |= __put_user(handler, &sc->handler);
163 if (set != NULL)
164 err |= __put_user(set->sig[0], &sc->oldmask);
165
166 return err;
167}
168
169/*
170 * Restore the sigcontext from the signal frame.
171 */
172
173static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
174 struct sigcontext __user *sc)
175{
176#ifdef CONFIG_ALTIVEC
177 elf_vrreg_t __user *v_regs;
178#endif
179 unsigned long err = 0;
180 unsigned long save_r13 = 0;
181 elf_greg_t *gregs = (elf_greg_t *)regs;
182#ifdef CONFIG_ALTIVEC
183 unsigned long msr;
184#endif
185 int i;
186
187 /* If this is not a signal return, we preserve the TLS in r13 */
188 if (!sig)
189 save_r13 = regs->gpr[13];
190
191 /* copy everything before MSR */
192 err |= __copy_from_user(regs, &sc->gp_regs,
193 PT_MSR*sizeof(unsigned long));
194
195 /* skip MSR and SOFTE */
196 for (i = PT_MSR+1; i <= PT_RESULT; i++) {
197 if (i == PT_SOFTE)
198 continue;
199 err |= __get_user(gregs[i], &sc->gp_regs[i]);
200 }
201
202 if (!sig)
203 regs->gpr[13] = save_r13;
204 err |= __copy_from_user(&current->thread.fpr, &sc->fp_regs, FP_REGS_SIZE);
205 if (set != NULL)
206 err |= __get_user(set->sig[0], &sc->oldmask);
207
208#ifdef CONFIG_ALTIVEC
209 err |= __get_user(v_regs, &sc->v_regs);
210 err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
211 if (err)
212 return err;
213 /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
214 if (v_regs != 0 && (msr & MSR_VEC) != 0)
215 err |= __copy_from_user(current->thread.vr, v_regs,
216 33 * sizeof(vector128));
217 else if (current->thread.used_vr)
218 memset(current->thread.vr, 0, 33 * sizeof(vector128));
219 /* Always get VRSAVE back */
220 if (v_regs != 0)
221 err |= __get_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
222 else
223 current->thread.vrsave = 0;
224#endif /* CONFIG_ALTIVEC */
225
226#ifndef CONFIG_SMP
227 preempt_disable();
228 if (last_task_used_math == current)
229 last_task_used_math = NULL;
230 if (last_task_used_altivec == current)
231 last_task_used_altivec = NULL;
232 preempt_enable();
233#endif
234 /* Force reload of FP/VEC */
235 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC);
236
237 return err;
238}
239
240/*
241 * Allocate space for the signal frame
242 */
243static inline void __user * get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
244 size_t frame_size)
245{
246 unsigned long newsp;
247
248 /* Default to using normal stack */
249 newsp = regs->gpr[1];
250
251 if (ka->sa.sa_flags & SA_ONSTACK) {
252 if (! on_sig_stack(regs->gpr[1]))
253 newsp = (current->sas_ss_sp + current->sas_ss_size);
254 }
255
256 return (void __user *)((newsp - frame_size) & -16ul);
257}
258
259/*
260 * Setup the trampoline code on the stack
261 */
262static long setup_trampoline(unsigned int syscall, unsigned int __user *tramp)
263{
264 int i;
265 long err = 0;
266
267 /* addi r1, r1, __SIGNAL_FRAMESIZE # Pop the dummy stackframe */
268 err |= __put_user(0x38210000UL | (__SIGNAL_FRAMESIZE & 0xffff), &tramp[0]);
269 /* li r0, __NR_[rt_]sigreturn| */
270 err |= __put_user(0x38000000UL | (syscall & 0xffff), &tramp[1]);
271 /* sc */
272 err |= __put_user(0x44000002UL, &tramp[2]);
273
274 /* Minimal traceback info */
275 for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)
276 err |= __put_user(0, &tramp[i]);
277
278 if (!err)
279 flush_icache_range((unsigned long) &tramp[0],
280 (unsigned long) &tramp[TRAMP_SIZE]);
281
282 return err;
283}
284
285/*
286 * Restore the user process's signal mask (also used by signal32.c)
287 */
288void restore_sigmask(sigset_t *set)
289{
290 sigdelsetmask(set, ~_BLOCKABLE);
291 spin_lock_irq(&current->sighand->siglock);
292 current->blocked = *set;
293 recalc_sigpending();
294 spin_unlock_irq(&current->sighand->siglock);
295}
296
297
298/*
299 * Handle {get,set,swap}_context operations
300 */
301int sys_swapcontext(struct ucontext __user *old_ctx,
302 struct ucontext __user *new_ctx,
303 long ctx_size, long r6, long r7, long r8, struct pt_regs *regs)
304{
305 unsigned char tmp;
306 sigset_t set;
307
308 /* Context size is for future use. Right now, we only make sure
309 * we are passed something we understand
310 */
311 if (ctx_size < sizeof(struct ucontext))
312 return -EINVAL;
313
314 if (old_ctx != NULL) {
315 if (!access_ok(VERIFY_WRITE, old_ctx, sizeof(*old_ctx))
316 || setup_sigcontext(&old_ctx->uc_mcontext, regs, 0, NULL, 0)
317 || __copy_to_user(&old_ctx->uc_sigmask,
318 &current->blocked, sizeof(sigset_t)))
319 return -EFAULT;
320 }
321 if (new_ctx == NULL)
322 return 0;
323 if (!access_ok(VERIFY_READ, new_ctx, sizeof(*new_ctx))
324 || __get_user(tmp, (u8 __user *) new_ctx)
325 || __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1))
326 return -EFAULT;
327
328 /*
329 * If we get a fault copying the context into the kernel's
330 * image of the user's registers, we can't just return -EFAULT
331 * because the user's registers will be corrupted. For instance
332 * the NIP value may have been updated but not some of the
333 * other registers. Given that we have done the access_ok
334 * and successfully read the first and last bytes of the region
335 * above, this should only happen in an out-of-memory situation
336 * or if another thread unmaps the region containing the context.
337 * We kill the task with a SIGSEGV in this situation.
338 */
339
340 if (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
341 do_exit(SIGSEGV);
342 restore_sigmask(&set);
343 if (restore_sigcontext(regs, NULL, 0, &new_ctx->uc_mcontext))
344 do_exit(SIGSEGV);
345
346 /* This returns like rt_sigreturn */
347 return 0;
348}
349
350
351/*
352 * Do a signal return; undo the signal stack.
353 */
354
355int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
356 unsigned long r6, unsigned long r7, unsigned long r8,
357 struct pt_regs *regs)
358{
359 struct ucontext __user *uc = (struct ucontext __user *)regs->gpr[1];
360 sigset_t set;
361
362 /* Always make any pending restarted system calls return -EINTR */
363 current_thread_info()->restart_block.fn = do_no_restart_syscall;
364
365 if (!access_ok(VERIFY_READ, uc, sizeof(*uc)))
366 goto badframe;
367
368 if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
369 goto badframe;
370 restore_sigmask(&set);
371 if (restore_sigcontext(regs, NULL, 1, &uc->uc_mcontext))
372 goto badframe;
373
374 /* do_sigaltstack expects a __user pointer and won't modify
375 * what's in there anyway
376 */
377 do_sigaltstack(&uc->uc_stack, NULL, regs->gpr[1]);
378
379 return regs->result;
380
381badframe:
382#if DEBUG_SIG
383 printk("badframe in sys_rt_sigreturn, regs=%p uc=%p &uc->uc_mcontext=%p\n",
384 regs, uc, &uc->uc_mcontext);
385#endif
386 force_sig(SIGSEGV, current);
387 return 0;
388}
389
390static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info,
391 sigset_t *set, struct pt_regs *regs)
392{
393 /* Handler is *really* a pointer to the function descriptor for
394 * the signal routine. The first entry in the function
395 * descriptor is the entry address of signal and the second
396 * entry is the TOC value we need to use.
397 */
398 func_descr_t __user *funct_desc_ptr;
399 struct rt_sigframe __user *frame;
400 unsigned long newsp = 0;
401 long err = 0;
402
403 frame = get_sigframe(ka, regs, sizeof(*frame));
404
405 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
406 goto badframe;
407
408 err |= __put_user(&frame->info, &frame->pinfo);
409 err |= __put_user(&frame->uc, &frame->puc);
410 err |= copy_siginfo_to_user(&frame->info, info);
411 if (err)
412 goto badframe;
413
414 /* Create the ucontext. */
415 err |= __put_user(0, &frame->uc.uc_flags);
416 err |= __put_user(0, &frame->uc.uc_link);
417 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
418 err |= __put_user(sas_ss_flags(regs->gpr[1]),
419 &frame->uc.uc_stack.ss_flags);
420 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
421 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, signr, NULL,
422 (unsigned long)ka->sa.sa_handler);
423 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
424 if (err)
425 goto badframe;
426
427 /* Set up to return from userspace. */
428 if (vdso64_rt_sigtramp && current->thread.vdso_base) {
429 regs->link = current->thread.vdso_base + vdso64_rt_sigtramp;
430 } else {
431 err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
432 if (err)
433 goto badframe;
434 regs->link = (unsigned long) &frame->tramp[0];
435 }
436 funct_desc_ptr = (func_descr_t __user *) ka->sa.sa_handler;
437
438 /* Allocate a dummy caller frame for the signal handler. */
439 newsp = (unsigned long)frame - __SIGNAL_FRAMESIZE;
440 err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
441
442 /* Set up "regs" so we "return" to the signal handler. */
443 err |= get_user(regs->nip, &funct_desc_ptr->entry);
444 regs->gpr[1] = newsp;
445 err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
446 regs->gpr[3] = signr;
447 regs->result = 0;
448 if (ka->sa.sa_flags & SA_SIGINFO) {
449 err |= get_user(regs->gpr[4], (unsigned long __user *)&frame->pinfo);
450 err |= get_user(regs->gpr[5], (unsigned long __user *)&frame->puc);
451 regs->gpr[6] = (unsigned long) frame;
452 } else {
453 regs->gpr[4] = (unsigned long)&frame->uc.uc_mcontext;
454 }
455 if (err)
456 goto badframe;
457
458 if (test_thread_flag(TIF_SINGLESTEP))
459 ptrace_notify(SIGTRAP);
460
461 return 1;
462
463badframe:
464#if DEBUG_SIG
465 printk("badframe in setup_rt_frame, regs=%p frame=%p newsp=%lx\n",
466 regs, frame, newsp);
467#endif
468 force_sigsegv(signr, current);
469 return 0;
470}
471
472
473/*
474 * OK, we're invoking a handler
475 */
476static int handle_signal(unsigned long sig, struct k_sigaction *ka,
477 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
478{
479 int ret;
480
481 /* Set up Signal Frame */
482 ret = setup_rt_frame(sig, ka, info, oldset, regs);
483
484 if (ret) {
485 spin_lock_irq(&current->sighand->siglock);
486 sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
487 if (!(ka->sa.sa_flags & SA_NODEFER))
488 sigaddset(&current->blocked,sig);
489 recalc_sigpending();
490 spin_unlock_irq(&current->sighand->siglock);
491 }
492
493 return ret;
494}
495
496static inline void syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
497{
498 switch ((int)regs->result) {
499 case -ERESTART_RESTARTBLOCK:
500 case -ERESTARTNOHAND:
501 /* ERESTARTNOHAND means that the syscall should only be
502 * restarted if there was no handler for the signal, and since
503 * we only get here if there is a handler, we dont restart.
504 */
505 regs->result = -EINTR;
506 break;
507 case -ERESTARTSYS:
508 /* ERESTARTSYS means to restart the syscall if there is no
509 * handler or the handler was registered with SA_RESTART
510 */
511 if (!(ka->sa.sa_flags & SA_RESTART)) {
512 regs->result = -EINTR;
513 break;
514 }
515 /* fallthrough */
516 case -ERESTARTNOINTR:
517 /* ERESTARTNOINTR means that the syscall should be
518 * called again after the signal handler returns.
519 */
520 regs->gpr[3] = regs->orig_gpr3;
521 regs->nip -= 4;
522 regs->result = 0;
523 break;
524 }
525}
526
527/*
528 * Note that 'init' is a special process: it doesn't get signals it doesn't
529 * want to handle. Thus you cannot kill init even with a SIGKILL even by
530 * mistake.
531 */
532int do_signal(sigset_t *oldset, struct pt_regs *regs)
533{
534 siginfo_t info;
535 int signr;
536 struct k_sigaction ka;
537
538 /*
539 * If the current thread is 32 bit - invoke the
540 * 32 bit signal handling code
541 */
542 if (test_thread_flag(TIF_32BIT))
543 return do_signal32(oldset, regs);
544
545 if (!oldset)
546 oldset = &current->blocked;
547
548 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
549 if (signr > 0) {
550 /* Whee! Actually deliver the signal. */
551 if (TRAP(regs) == 0x0C00)
552 syscall_restart(regs, &ka);
553
554 /*
555 * Reenable the DABR before delivering the signal to
556 * user space. The DABR will have been cleared if it
557 * triggered inside the kernel.
558 */
559 if (current->thread.dabr)
560 set_dabr(current->thread.dabr);
561
562 return handle_signal(signr, &ka, &info, oldset, regs);
563 }
564
565 if (TRAP(regs) == 0x0C00) { /* System Call! */
566 if ((int)regs->result == -ERESTARTNOHAND ||
567 (int)regs->result == -ERESTARTSYS ||
568 (int)regs->result == -ERESTARTNOINTR) {
569 regs->gpr[3] = regs->orig_gpr3;
570 regs->nip -= 4; /* Back up & retry system call */
571 regs->result = 0;
572 } else if ((int)regs->result == -ERESTART_RESTARTBLOCK) {
573 regs->gpr[0] = __NR_restart_syscall;
574 regs->nip -= 4;
575 regs->result = 0;
576 }
577 }
578
579 return 0;
580}
581EXPORT_SYMBOL(do_signal);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-17 20:21:29 -0500