2 * linux/arch/parisc/kernel/signal.c: Architecture-specific signal
5 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
6 * Copyright (C) 2000 Linuxcare, Inc.
8 * Based on the ia64, i386, and alpha versions.
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.
16 #include <linux/sched.h>
18 #include <linux/smp.h>
19 #include <linux/kernel.h>
20 #include <linux/signal.h>
21 #include <linux/errno.h>
22 #include <linux/wait.h>
23 #include <linux/ptrace.h>
24 #include <linux/tracehook.h>
25 #include <linux/unistd.h>
26 #include <linux/stddef.h>
27 #include <linux/compat.h>
28 #include <linux/elf.h>
29 #include <asm/ucontext.h>
30 #include <asm/rt_sigframe.h>
31 #include <asm/uaccess.h>
32 #include <asm/pgalloc.h>
33 #include <asm/cacheflush.h>
34 #include <asm/asm-offsets.h>
41 #define DEBUG_SIG_LEVEL 2
44 #define DBG(LEVEL, ...) \
45 ((DEBUG_SIG_LEVEL >= LEVEL) \
46 ? printk(__VA_ARGS__) : (void) 0)
48 #define DBG(LEVEL, ...)
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
56 #define A(__x) ((unsigned long)(__x))
59 * Atomically swap in the new signal mask, and wait for a signal.
66 * Do a signal return - restore sigcontext.
69 /* Trampoline for calling rt_sigreturn() */
70 #define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */
71 #define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */
72 #define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */
73 #define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */
74 #define INSN_NOP 0x08000240 /* nop */
76 #define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */
79 restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
83 err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr));
84 err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr));
85 err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq));
86 err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq));
87 err |= __get_user(regs->sar, &sc->sc_sar);
88 DBG(2,"restore_sigcontext: iaoq is 0x%#lx / 0x%#lx\n",
89 regs->iaoq[0],regs->iaoq[1]);
90 DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]);
95 sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
97 struct rt_sigframe __user *frame;
99 unsigned long usp = (regs->gr[30] & ~(0x01UL));
100 unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE;
102 compat_sigset_t compat_set;
103 struct compat_rt_sigframe __user * compat_frame;
105 if (is_compat_task())
106 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
109 current_thread_info()->restart_block.fn = do_no_restart_syscall;
111 /* Unwind the user stack to get the rt_sigframe structure. */
112 frame = (struct rt_sigframe __user *)
113 (usp - sigframe_size);
114 DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
116 regs->orig_r28 = 1; /* no restarts for sigreturn */
119 compat_frame = (struct compat_rt_sigframe __user *)frame;
121 if (is_compat_task()) {
122 DBG(2,"sys_rt_sigreturn: ELF32 process.\n");
123 if (__copy_from_user(&compat_set, &compat_frame->uc.uc_sigmask, sizeof(compat_set)))
125 sigset_32to64(&set,&compat_set);
129 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
133 set_current_blocked(&set);
135 /* Good thing we saved the old gr[30], eh? */
137 if (is_compat_task()) {
138 DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n",
139 &compat_frame->uc.uc_mcontext);
140 // FIXME: Load upper half from register file
141 if (restore_sigcontext32(&compat_frame->uc.uc_mcontext,
142 &compat_frame->regs, regs))
144 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
145 usp, &compat_frame->uc.uc_stack);
146 if (compat_restore_altstack(&compat_frame->uc.uc_stack))
151 DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n",
152 &frame->uc.uc_mcontext);
153 if (restore_sigcontext(&frame->uc.uc_mcontext, regs))
155 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
156 usp, &frame->uc.uc_stack);
157 if (restore_altstack(&frame->uc.uc_stack))
163 /* If we are on the syscall path IAOQ will not be restored, and
164 * if we are on the interrupt path we must not corrupt gr31.
167 regs->gr[31] = regs->iaoq[0];
169 DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]);
175 DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n");
176 force_sig(SIGSEGV, current);
181 * Set up a signal frame.
184 static inline void __user *
185 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
187 /*FIXME: ELF32 vs. ELF64 has different frame_size, but since we
188 don't use the parameter it doesn't matter */
190 DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
191 (unsigned long)ka, sp, frame_size);
193 /* Align alternate stack and reserve 64 bytes for the signal
194 handler's frame marker. */
195 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
196 sp = (current->sas_ss_sp + 0x7f) & ~0x3f; /* Stacks grow up! */
198 DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
199 return (void __user *) sp; /* Stacks grow up. Fun. */
203 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
206 unsigned long flags = 0;
209 if (on_sig_stack((unsigned long) sc))
210 flags |= PARISC_SC_FLAG_ONSTACK;
212 flags |= PARISC_SC_FLAG_IN_SYSCALL;
213 /* regs->iaoq is undefined in the syscall return path */
214 err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
215 err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
216 err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
217 err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
218 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
219 regs->gr[31], regs->gr[31]+4);
221 err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
222 err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
223 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
224 regs->iaoq[0], regs->iaoq[1]);
227 err |= __put_user(flags, &sc->sc_flags);
228 err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
229 err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
230 err |= __put_user(regs->sar, &sc->sc_sar);
231 DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
237 setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
238 sigset_t *set, struct pt_regs *regs, int in_syscall)
240 struct rt_sigframe __user *frame;
241 unsigned long rp, usp;
242 unsigned long haddr, sigframe_size;
245 compat_int_t compat_val;
246 struct compat_rt_sigframe __user * compat_frame;
247 compat_sigset_t compat_set;
250 usp = (regs->gr[30] & ~(0x01UL));
251 /*FIXME: frame_size parameter is unused, remove it. */
252 frame = get_sigframe(ka, usp, sizeof(*frame));
254 DBG(1,"SETUP_RT_FRAME: START\n");
255 DBG(1,"setup_rt_frame: frame %p info %p\n", frame, info);
260 compat_frame = (struct compat_rt_sigframe __user *)frame;
262 if (is_compat_task()) {
263 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
264 err |= copy_siginfo_to_user32(&compat_frame->info, info);
265 err |= __compat_save_altstack( &compat_frame->uc.uc_stack, regs->gr[30]);
266 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
267 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
268 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
269 &compat_frame->regs, regs, in_syscall);
270 sigset_64to32(&compat_set,set);
271 err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
275 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
276 err |= copy_siginfo_to_user(&frame->info, info);
277 err |= __save_altstack(&frame->uc.uc_stack, regs->gr[30]);
278 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
279 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
280 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
281 /* FIXME: Should probably be converted as well for the compat case */
282 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
288 /* Set up to return from userspace. If provided, use a stub
289 already in userspace. The first words of tramp are used to
290 save the previous sigrestartblock trampoline that might be
291 on the stack. We start the sigreturn trampoline at
292 SIGRESTARTBLOCK_TRAMP+X. */
293 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
294 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
295 err |= __put_user(INSN_LDI_R20,
296 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
297 err |= __put_user(INSN_BLE_SR2_R0,
298 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
299 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
302 /* Assert that we're flushing in the correct space... */
305 asm ("mfsp %%sr3,%0" : "=r" (sid));
306 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
311 flush_user_dcache_range((unsigned long) &frame->tramp[0],
312 (unsigned long) &frame->tramp[TRAMP_SIZE]);
313 flush_user_icache_range((unsigned long) &frame->tramp[0],
314 (unsigned long) &frame->tramp[TRAMP_SIZE]);
316 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
317 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
318 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
320 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
325 haddr = A(ka->sa.sa_handler);
326 /* The sa_handler may be a pointer to a function descriptor */
328 if (is_compat_task()) {
330 if (haddr & PA_PLABEL_FDESC) {
332 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
334 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
340 regs->gr[19] = fdesc.gp;
345 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
347 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
353 regs->gr[19] = fdesc.gp;
354 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
355 haddr, regs->gr[19], in_syscall);
359 /* The syscall return path will create IAOQ values from r31.
361 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
363 if (is_compat_task())
364 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
367 regs->gr[31] = haddr;
369 if (!test_thread_flag(TIF_32BIT))
373 unsigned long psw = USER_PSW;
375 if (!test_thread_flag(TIF_32BIT))
379 /* If we are singlestepping, arrange a trap to be delivered
380 when we return to userspace. Note the semantics -- we
381 should trap before the first insn in the handler is
383 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
385 if (pa_psw(current)->r) {
386 pa_psw(current)->r = 0;
392 regs->iaoq[0] = haddr | 3;
393 regs->iaoq[1] = regs->iaoq[0] + 4;
396 regs->gr[2] = rp; /* userland return pointer */
397 regs->gr[26] = sig; /* signal number */
400 if (is_compat_task()) {
401 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
402 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
406 regs->gr[25] = A(&frame->info); /* siginfo pointer */
407 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
410 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
411 regs->gr[30], sigframe_size,
412 regs->gr[30] + sigframe_size);
413 /* Raise the user stack pointer to make a proper call frame. */
414 regs->gr[30] = (A(frame) + sigframe_size);
417 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
418 current->comm, current->pid, frame, regs->gr[30],
419 regs->iaoq[0], regs->iaoq[1], rp);
424 DBG(1,"setup_rt_frame: sending SIGSEGV\n");
425 force_sigsegv(sig, current);
430 * OK, we're invoking a handler.
434 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
435 struct pt_regs *regs, int in_syscall)
437 sigset_t *oldset = sigmask_to_save();
438 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
439 sig, ka, info, oldset, regs);
441 /* Set up the stack frame */
442 if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
445 signal_delivered(sig, info, ka, regs,
446 test_thread_flag(TIF_SINGLESTEP) ||
447 test_thread_flag(TIF_BLOCKSTEP));
449 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
454 syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
458 regs->orig_r28 = 1; /* no more restarts */
459 /* Check the return code */
460 switch (regs->gr[28]) {
461 case -ERESTART_RESTARTBLOCK:
462 case -ERESTARTNOHAND:
463 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
464 regs->gr[28] = -EINTR;
468 if (!(ka->sa.sa_flags & SA_RESTART)) {
469 DBG(1,"ERESTARTSYS: putting -EINTR\n");
470 regs->gr[28] = -EINTR;
474 case -ERESTARTNOINTR:
475 /* A syscall is just a branch, so all
476 * we have to do is fiddle the return pointer.
478 regs->gr[31] -= 8; /* delayed branching */
484 insert_restart_trampoline(struct pt_regs *regs)
488 regs->orig_r28 = 1; /* no more restarts */
489 switch(regs->gr[28]) {
490 case -ERESTART_RESTARTBLOCK: {
491 /* Restart the system call - no handlers present */
492 unsigned int *usp = (unsigned int *)regs->gr[30];
494 /* Setup a trampoline to restart the syscall
495 * with __NR_restart_syscall
497 * 0: <return address (orig r31)>
498 * 4: <2nd half for 64-bit>
499 * 8: ldw 0(%sp), %r31
500 * 12: be 0x100(%sr2, %r0)
501 * 16: ldi __NR_restart_syscall, %r20
504 put_user(regs->gr[31] >> 32, &usp[0]);
505 put_user(regs->gr[31] & 0xffffffff, &usp[1]);
506 put_user(0x0fc010df, &usp[2]);
508 put_user(regs->gr[31], &usp[0]);
509 put_user(0x0fc0109f, &usp[2]);
511 put_user(0xe0008200, &usp[3]);
512 put_user(0x34140000, &usp[4]);
514 /* Stack is 64-byte aligned, and we only need
515 * to flush 1 cache line.
516 * Flushing one cacheline is cheap.
517 * "sync" on bigger (> 4 way) boxes is not.
519 flush_user_dcache_range(regs->gr[30], regs->gr[30] + 4);
520 flush_user_icache_range(regs->gr[30], regs->gr[30] + 4);
522 regs->gr[31] = regs->gr[30] + 8;
525 case -ERESTARTNOHAND:
527 case -ERESTARTNOINTR: {
528 /* Hooray for delayed branching. We don't
529 * have to restore %r20 (the system call
530 * number) because it gets loaded in the delay
531 * slot of the branch external instruction.
542 * Note that 'init' is a special process: it doesn't get signals it doesn't
543 * want to handle. Thus you cannot kill init even with a SIGKILL even by
546 * We need to be able to restore the syscall arguments (r21-r26) to
547 * restart syscalls. Thus, the syscall path should save them in the
548 * pt_regs structure (it's okay to do so since they are caller-save
549 * registers). As noted below, the syscall number gets restored for
550 * us due to the magic of delayed branching.
553 do_signal(struct pt_regs *regs, long in_syscall)
556 struct k_sigaction ka;
559 DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
560 regs, regs->sr[7], in_syscall);
562 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
563 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
566 /* Restart a system call if necessary. */
568 syscall_restart(regs, &ka);
570 handle_signal(signr, &info, &ka, regs, in_syscall);
574 /* Did we come from a system call? */
576 insert_restart_trampoline(regs);
578 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
581 restore_saved_sigmask();
584 void do_notify_resume(struct pt_regs *regs, long in_syscall)
586 if (test_thread_flag(TIF_SIGPENDING))
587 do_signal(regs, in_syscall);
589 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
590 clear_thread_flag(TIF_NOTIFY_RESUME);
591 tracehook_notify_resume(regs);