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 (do_sigaltstack32(&compat_frame->uc.uc_stack, NULL, usp) == -EFAULT)
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 (do_sigaltstack(&frame->uc.uc_stack, NULL, usp) == -EFAULT)
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 DBG(1,"SETUP_RT_FRAME: 1\n");
264 compat_val = (compat_int_t)current->sas_ss_sp;
265 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_sp);
266 DBG(1,"SETUP_RT_FRAME: 2\n");
267 compat_val = (compat_int_t)current->sas_ss_size;
268 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_size);
269 DBG(1,"SETUP_RT_FRAME: 3\n");
270 compat_val = sas_ss_flags(regs->gr[30]);
271 err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_flags);
272 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
273 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
274 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
275 &compat_frame->regs, regs, in_syscall);
276 sigset_64to32(&compat_set,set);
277 err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
281 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
282 err |= copy_siginfo_to_user(&frame->info, info);
283 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
284 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
285 err |= __put_user(sas_ss_flags(regs->gr[30]),
286 &frame->uc.uc_stack.ss_flags);
287 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
288 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
289 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
290 /* FIXME: Should probably be converted as well for the compat case */
291 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
297 /* Set up to return from userspace. If provided, use a stub
298 already in userspace. The first words of tramp are used to
299 save the previous sigrestartblock trampoline that might be
300 on the stack. We start the sigreturn trampoline at
301 SIGRESTARTBLOCK_TRAMP+X. */
302 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
303 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
304 err |= __put_user(INSN_LDI_R20,
305 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
306 err |= __put_user(INSN_BLE_SR2_R0,
307 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
308 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
311 /* Assert that we're flushing in the correct space... */
314 asm ("mfsp %%sr3,%0" : "=r" (sid));
315 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
320 flush_user_dcache_range((unsigned long) &frame->tramp[0],
321 (unsigned long) &frame->tramp[TRAMP_SIZE]);
322 flush_user_icache_range((unsigned long) &frame->tramp[0],
323 (unsigned long) &frame->tramp[TRAMP_SIZE]);
325 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
326 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
327 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
329 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
334 haddr = A(ka->sa.sa_handler);
335 /* The sa_handler may be a pointer to a function descriptor */
337 if (is_compat_task()) {
339 if (haddr & PA_PLABEL_FDESC) {
341 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
343 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
349 regs->gr[19] = fdesc.gp;
354 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
356 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
362 regs->gr[19] = fdesc.gp;
363 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
364 haddr, regs->gr[19], in_syscall);
368 /* The syscall return path will create IAOQ values from r31.
370 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
372 if (is_compat_task())
373 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
376 regs->gr[31] = haddr;
378 if (!test_thread_flag(TIF_32BIT))
382 unsigned long psw = USER_PSW;
384 if (!test_thread_flag(TIF_32BIT))
388 /* If we are singlestepping, arrange a trap to be delivered
389 when we return to userspace. Note the semantics -- we
390 should trap before the first insn in the handler is
392 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
394 if (pa_psw(current)->r) {
395 pa_psw(current)->r = 0;
401 regs->iaoq[0] = haddr | 3;
402 regs->iaoq[1] = regs->iaoq[0] + 4;
405 regs->gr[2] = rp; /* userland return pointer */
406 regs->gr[26] = sig; /* signal number */
409 if (is_compat_task()) {
410 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
411 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
415 regs->gr[25] = A(&frame->info); /* siginfo pointer */
416 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
419 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
420 regs->gr[30], sigframe_size,
421 regs->gr[30] + sigframe_size);
422 /* Raise the user stack pointer to make a proper call frame. */
423 regs->gr[30] = (A(frame) + sigframe_size);
426 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
427 current->comm, current->pid, frame, regs->gr[30],
428 regs->iaoq[0], regs->iaoq[1], rp);
433 DBG(1,"setup_rt_frame: sending SIGSEGV\n");
434 force_sigsegv(sig, current);
439 * OK, we're invoking a handler.
443 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
444 struct pt_regs *regs, int in_syscall)
446 sigset_t *oldset = sigmask_to_save();
447 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
448 sig, ka, info, oldset, regs);
450 /* Set up the stack frame */
451 if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
454 signal_delivered(sig, info, ka, regs,
455 test_thread_flag(TIF_SINGLESTEP) ||
456 test_thread_flag(TIF_BLOCKSTEP));
458 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
463 syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
467 regs->orig_r28 = 1; /* no more restarts */
468 /* Check the return code */
469 switch (regs->gr[28]) {
470 case -ERESTART_RESTARTBLOCK:
471 case -ERESTARTNOHAND:
472 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
473 regs->gr[28] = -EINTR;
477 if (!(ka->sa.sa_flags & SA_RESTART)) {
478 DBG(1,"ERESTARTSYS: putting -EINTR\n");
479 regs->gr[28] = -EINTR;
483 case -ERESTARTNOINTR:
484 /* A syscall is just a branch, so all
485 * we have to do is fiddle the return pointer.
487 regs->gr[31] -= 8; /* delayed branching */
493 insert_restart_trampoline(struct pt_regs *regs)
497 regs->orig_r28 = 1; /* no more restarts */
498 switch(regs->gr[28]) {
499 case -ERESTART_RESTARTBLOCK: {
500 /* Restart the system call - no handlers present */
501 unsigned int *usp = (unsigned int *)regs->gr[30];
503 /* Setup a trampoline to restart the syscall
504 * with __NR_restart_syscall
506 * 0: <return address (orig r31)>
507 * 4: <2nd half for 64-bit>
508 * 8: ldw 0(%sp), %r31
509 * 12: be 0x100(%sr2, %r0)
510 * 16: ldi __NR_restart_syscall, %r20
513 put_user(regs->gr[31] >> 32, &usp[0]);
514 put_user(regs->gr[31] & 0xffffffff, &usp[1]);
515 put_user(0x0fc010df, &usp[2]);
517 put_user(regs->gr[31], &usp[0]);
518 put_user(0x0fc0109f, &usp[2]);
520 put_user(0xe0008200, &usp[3]);
521 put_user(0x34140000, &usp[4]);
523 /* Stack is 64-byte aligned, and we only need
524 * to flush 1 cache line.
525 * Flushing one cacheline is cheap.
526 * "sync" on bigger (> 4 way) boxes is not.
528 flush_user_dcache_range(regs->gr[30], regs->gr[30] + 4);
529 flush_user_icache_range(regs->gr[30], regs->gr[30] + 4);
531 regs->gr[31] = regs->gr[30] + 8;
534 case -ERESTARTNOHAND:
536 case -ERESTARTNOINTR: {
537 /* Hooray for delayed branching. We don't
538 * have to restore %r20 (the system call
539 * number) because it gets loaded in the delay
540 * slot of the branch external instruction.
551 * Note that 'init' is a special process: it doesn't get signals it doesn't
552 * want to handle. Thus you cannot kill init even with a SIGKILL even by
555 * We need to be able to restore the syscall arguments (r21-r26) to
556 * restart syscalls. Thus, the syscall path should save them in the
557 * pt_regs structure (it's okay to do so since they are caller-save
558 * registers). As noted below, the syscall number gets restored for
559 * us due to the magic of delayed branching.
562 do_signal(struct pt_regs *regs, long in_syscall)
565 struct k_sigaction ka;
568 DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
569 regs, regs->sr[7], in_syscall);
571 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
572 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
575 /* Restart a system call if necessary. */
577 syscall_restart(regs, &ka);
579 handle_signal(signr, &info, &ka, regs, in_syscall);
583 /* Did we come from a system call? */
585 insert_restart_trampoline(regs);
587 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
590 restore_saved_sigmask();
593 void do_notify_resume(struct pt_regs *regs, long in_syscall)
595 if (test_thread_flag(TIF_SIGPENDING))
596 do_signal(regs, in_syscall);
598 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
599 clear_thread_flag(TIF_NOTIFY_RESUME);
600 tracehook_notify_resume(regs);