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 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
194 sp = current->sas_ss_sp; /* Stacks grow up! */
196 DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
197 return (void __user *) sp; /* Stacks grow up. Fun. */
201 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
204 unsigned long flags = 0;
207 if (on_sig_stack((unsigned long) sc))
208 flags |= PARISC_SC_FLAG_ONSTACK;
210 flags |= PARISC_SC_FLAG_IN_SYSCALL;
211 /* regs->iaoq is undefined in the syscall return path */
212 err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
213 err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
214 err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
215 err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
216 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
217 regs->gr[31], regs->gr[31]+4);
219 err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
220 err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
221 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
222 regs->iaoq[0], regs->iaoq[1]);
225 err |= __put_user(flags, &sc->sc_flags);
226 err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
227 err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
228 err |= __put_user(regs->sar, &sc->sc_sar);
229 DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
235 setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
236 sigset_t *set, struct pt_regs *regs, int in_syscall)
238 struct rt_sigframe __user *frame;
239 unsigned long rp, usp;
240 unsigned long haddr, sigframe_size;
243 compat_int_t compat_val;
244 struct compat_rt_sigframe __user * compat_frame;
245 compat_sigset_t compat_set;
248 usp = (regs->gr[30] & ~(0x01UL));
249 /*FIXME: frame_size parameter is unused, remove it. */
250 frame = get_sigframe(ka, usp, sizeof(*frame));
252 DBG(1,"SETUP_RT_FRAME: START\n");
253 DBG(1,"setup_rt_frame: frame %p info %p\n", frame, info);
258 compat_frame = (struct compat_rt_sigframe __user *)frame;
260 if (is_compat_task()) {
261 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
262 err |= copy_siginfo_to_user32(&compat_frame->info, info);
263 err |= __compat_save_altstack( &compat_frame->uc.uc_stack, regs->gr[30]);
264 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
265 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
266 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
267 &compat_frame->regs, regs, in_syscall);
268 sigset_64to32(&compat_set,set);
269 err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
273 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
274 err |= copy_siginfo_to_user(&frame->info, info);
275 err |= __save_altstack(&frame->uc.uc_stack, regs->gr[30]);
276 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
277 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
278 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
279 /* FIXME: Should probably be converted as well for the compat case */
280 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
286 /* Set up to return from userspace. If provided, use a stub
287 already in userspace. The first words of tramp are used to
288 save the previous sigrestartblock trampoline that might be
289 on the stack. We start the sigreturn trampoline at
290 SIGRESTARTBLOCK_TRAMP+X. */
291 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
292 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
293 err |= __put_user(INSN_LDI_R20,
294 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
295 err |= __put_user(INSN_BLE_SR2_R0,
296 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
297 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
300 /* Assert that we're flushing in the correct space... */
303 asm ("mfsp %%sr3,%0" : "=r" (sid));
304 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
309 flush_user_dcache_range((unsigned long) &frame->tramp[0],
310 (unsigned long) &frame->tramp[TRAMP_SIZE]);
311 flush_user_icache_range((unsigned long) &frame->tramp[0],
312 (unsigned long) &frame->tramp[TRAMP_SIZE]);
314 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
315 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
316 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
318 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
323 haddr = A(ka->sa.sa_handler);
324 /* The sa_handler may be a pointer to a function descriptor */
326 if (is_compat_task()) {
328 if (haddr & PA_PLABEL_FDESC) {
330 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
332 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
338 regs->gr[19] = fdesc.gp;
343 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
345 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
351 regs->gr[19] = fdesc.gp;
352 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
353 haddr, regs->gr[19], in_syscall);
357 /* The syscall return path will create IAOQ values from r31.
359 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
361 if (is_compat_task())
362 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
365 regs->gr[31] = haddr;
367 if (!test_thread_flag(TIF_32BIT))
371 unsigned long psw = USER_PSW;
373 if (!test_thread_flag(TIF_32BIT))
377 /* If we are singlestepping, arrange a trap to be delivered
378 when we return to userspace. Note the semantics -- we
379 should trap before the first insn in the handler is
381 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
383 if (pa_psw(current)->r) {
384 pa_psw(current)->r = 0;
390 regs->iaoq[0] = haddr | 3;
391 regs->iaoq[1] = regs->iaoq[0] + 4;
394 regs->gr[2] = rp; /* userland return pointer */
395 regs->gr[26] = sig; /* signal number */
398 if (is_compat_task()) {
399 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
400 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
404 regs->gr[25] = A(&frame->info); /* siginfo pointer */
405 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
408 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
409 regs->gr[30], sigframe_size,
410 regs->gr[30] + sigframe_size);
411 /* Raise the user stack pointer to make a proper call frame. */
412 regs->gr[30] = (A(frame) + sigframe_size);
415 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
416 current->comm, current->pid, frame, regs->gr[30],
417 regs->iaoq[0], regs->iaoq[1], rp);
422 DBG(1,"setup_rt_frame: sending SIGSEGV\n");
423 force_sigsegv(sig, current);
428 * OK, we're invoking a handler.
432 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
433 struct pt_regs *regs, int in_syscall)
435 sigset_t *oldset = sigmask_to_save();
436 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
437 sig, ka, info, oldset, regs);
439 /* Set up the stack frame */
440 if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
443 signal_delivered(sig, info, ka, regs,
444 test_thread_flag(TIF_SINGLESTEP) ||
445 test_thread_flag(TIF_BLOCKSTEP));
447 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
452 syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
456 regs->orig_r28 = 1; /* no more restarts */
457 /* Check the return code */
458 switch (regs->gr[28]) {
459 case -ERESTART_RESTARTBLOCK:
460 case -ERESTARTNOHAND:
461 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
462 regs->gr[28] = -EINTR;
466 if (!(ka->sa.sa_flags & SA_RESTART)) {
467 DBG(1,"ERESTARTSYS: putting -EINTR\n");
468 regs->gr[28] = -EINTR;
472 case -ERESTARTNOINTR:
473 /* A syscall is just a branch, so all
474 * we have to do is fiddle the return pointer.
476 regs->gr[31] -= 8; /* delayed branching */
482 insert_restart_trampoline(struct pt_regs *regs)
486 regs->orig_r28 = 1; /* no more restarts */
487 switch(regs->gr[28]) {
488 case -ERESTART_RESTARTBLOCK: {
489 /* Restart the system call - no handlers present */
490 unsigned int *usp = (unsigned int *)regs->gr[30];
492 /* Setup a trampoline to restart the syscall
493 * with __NR_restart_syscall
495 * 0: <return address (orig r31)>
496 * 4: <2nd half for 64-bit>
497 * 8: ldw 0(%sp), %r31
498 * 12: be 0x100(%sr2, %r0)
499 * 16: ldi __NR_restart_syscall, %r20
502 put_user(regs->gr[31] >> 32, &usp[0]);
503 put_user(regs->gr[31] & 0xffffffff, &usp[1]);
504 put_user(0x0fc010df, &usp[2]);
506 put_user(regs->gr[31], &usp[0]);
507 put_user(0x0fc0109f, &usp[2]);
509 put_user(0xe0008200, &usp[3]);
510 put_user(0x34140000, &usp[4]);
512 /* Stack is 64-byte aligned, and we only need
513 * to flush 1 cache line.
514 * Flushing one cacheline is cheap.
515 * "sync" on bigger (> 4 way) boxes is not.
517 flush_user_dcache_range(regs->gr[30], regs->gr[30] + 4);
518 flush_user_icache_range(regs->gr[30], regs->gr[30] + 4);
520 regs->gr[31] = regs->gr[30] + 8;
523 case -ERESTARTNOHAND:
525 case -ERESTARTNOINTR: {
526 /* Hooray for delayed branching. We don't
527 * have to restore %r20 (the system call
528 * number) because it gets loaded in the delay
529 * slot of the branch external instruction.
540 * Note that 'init' is a special process: it doesn't get signals it doesn't
541 * want to handle. Thus you cannot kill init even with a SIGKILL even by
544 * We need to be able to restore the syscall arguments (r21-r26) to
545 * restart syscalls. Thus, the syscall path should save them in the
546 * pt_regs structure (it's okay to do so since they are caller-save
547 * registers). As noted below, the syscall number gets restored for
548 * us due to the magic of delayed branching.
551 do_signal(struct pt_regs *regs, long in_syscall)
554 struct k_sigaction ka;
557 DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
558 regs, regs->sr[7], in_syscall);
560 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
561 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
564 /* Restart a system call if necessary. */
566 syscall_restart(regs, &ka);
568 handle_signal(signr, &info, &ka, regs, in_syscall);
572 /* Did we come from a system call? */
574 insert_restart_trampoline(regs);
576 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
579 restore_saved_sigmask();
582 void do_notify_resume(struct pt_regs *regs, long in_syscall)
584 if (test_thread_flag(TIF_SIGPENDING))
585 do_signal(regs, in_syscall);
587 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
588 clear_thread_flag(TIF_NOTIFY_RESUME);
589 tracehook_notify_resume(regs);