1 /* $NetBSD: sig_machdep.c,v 1.20 2011/01/01 02:08:10 nisimura Exp $ */ 2 3 /*- 4 * Copyright (c) 2003 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> /* RCS ID & Copyright macro defns */ 33 34 __KERNEL_RCSID(0, "$NetBSD: sig_machdep.c,v 1.20 2011/01/01 02:08:10 nisimura Exp $"); 35 36 #include "opt_cputype.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/kernel.h> 41 #include <sys/proc.h> 42 #include <sys/signal.h> 43 #include <sys/signalvar.h> 44 #include <sys/mount.h> 45 #include <sys/syscallargs.h> 46 47 #include <machine/cpu.h> 48 49 #include <mips/frame.h> 50 #include <mips/regnum.h> 51 52 void * 53 getframe(struct lwp *l, int sig, int *onstack) 54 { 55 struct proc *p = l->l_proc; 56 struct frame *fp = l->l_md.md_regs; 57 58 /* Do we need to jump onto the signal stack? */ 59 *onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 60 && (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; 61 if (*onstack) 62 return (char *)l->l_sigstk.ss_sp + l->l_sigstk.ss_size; 63 return (void *)(intptr_t)fp->f_regs[_R_SP]; 64 } 65 66 struct sigframe_siginfo { 67 siginfo_t sf_si; 68 ucontext_t sf_uc; 69 }; 70 71 /* 72 * Send a signal to process. 73 */ 74 void 75 sendsig_siginfo(const ksiginfo_t *ksi, const sigset_t *mask) 76 { 77 struct lwp *l = curlwp; 78 struct proc *p = l->l_proc; 79 struct sigacts *ps = p->p_sigacts; 80 struct frame *tf; 81 struct sigframe_siginfo *fp, frame; 82 int onstack, error; 83 int sig = ksi->ksi_signo; 84 sig_t catcher = SIGACTION(p, sig).sa_handler; 85 86 fp = (struct sigframe_siginfo *)getframe(l, sig, &onstack) - 1; 87 88 frame.sf_si._info = ksi->ksi_info; 89 frame.sf_uc.uc_flags = _UC_SIGMASK 90 | ((l->l_sigstk.ss_flags & SS_ONSTACK) 91 ? _UC_SETSTACK : _UC_CLRSTACK); 92 frame.sf_uc.uc_sigmask = *mask; 93 frame.sf_uc.uc_link = l->l_ctxlink; 94 memset(&frame.sf_uc.uc_stack, 0, sizeof(frame.sf_uc.uc_stack)); 95 sendsig_reset(l, sig); 96 97 mutex_exit(p->p_lock); 98 cpu_getmcontext(l, &frame.sf_uc.uc_mcontext, &frame.sf_uc.uc_flags); 99 error = copyout(&frame, fp, sizeof(frame)); 100 mutex_enter(p->p_lock); 101 102 if (error != 0) { 103 /* 104 * Process has trashed its stack; give it an illegal 105 * instruction to halt it in its tracks. 106 */ 107 sigexit(l, SIGILL); 108 /* NOTREACHED */ 109 } 110 111 /* 112 * Set up the registers to directly invoke the signal 113 * handler. The return address will be set up to point 114 * to the signal trampoline to bounce us back. 115 */ 116 tf = l->l_md.md_regs; 117 tf->f_regs[_R_A0] = sig; 118 tf->f_regs[_R_A1] = (intptr_t)&fp->sf_si; 119 tf->f_regs[_R_A2] = (intptr_t)&fp->sf_uc; 120 121 tf->f_regs[_R_PC] = (intptr_t)catcher; 122 tf->f_regs[_R_T9] = (intptr_t)catcher; 123 tf->f_regs[_R_SP] = (intptr_t)fp; 124 tf->f_regs[_R_RA] = (intptr_t)ps->sa_sigdesc[sig].sd_tramp; 125 126 /* Remember that we're now on the signal stack. */ 127 if (onstack) 128 l->l_sigstk.ss_flags |= SS_ONSTACK; 129 } 130