1 /* 2 * Copyright (C) 2003 Broadcom Corporation 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 2 7 * of the License, or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 17 */ 18 #include <linux/cache.h> 19 #include <linux/sched.h> 20 #include <linux/mm.h> 21 #include <linux/smp.h> 22 #include <linux/kernel.h> 23 #include <linux/signal.h> 24 #include <linux/errno.h> 25 #include <linux/wait.h> 26 #include <linux/ptrace.h> 27 #include <linux/unistd.h> 28 #include <linux/compat.h> 29 #include <linux/bitops.h> 30 31 #include <asm/abi.h> 32 #include <asm/asm.h> 33 #include <asm/cacheflush.h> 34 #include <asm/compat-signal.h> 35 #include <asm/sim.h> 36 #include <asm/uaccess.h> 37 #include <asm/ucontext.h> 38 #include <asm/fpu.h> 39 #include <asm/cpu-features.h> 40 #include <asm/war.h> 41 #include <asm/vdso.h> 42 43 #include "signal-common.h" 44 45 /* 46 * Including <asm/unistd.h> would give use the 64-bit syscall numbers ... 47 */ 48 #define __NR_N32_restart_syscall 6214 49 50 extern int setup_sigcontext(struct pt_regs *, struct sigcontext __user *); 51 extern int restore_sigcontext(struct pt_regs *, struct sigcontext __user *); 52 53 struct ucontextn32 { 54 u32 uc_flags; 55 s32 uc_link; 56 compat_stack_t uc_stack; 57 struct sigcontext uc_mcontext; 58 compat_sigset_t uc_sigmask; /* mask last for extensibility */ 59 }; 60 61 struct rt_sigframe_n32 { 62 u32 rs_ass[4]; /* argument save space for o32 */ 63 u32 rs_pad[2]; /* Was: signal trampoline */ 64 struct compat_siginfo rs_info; 65 struct ucontextn32 rs_uc; 66 }; 67 68 asmlinkage void sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs) 69 { 70 struct rt_sigframe_n32 __user *frame; 71 sigset_t set; 72 int sig; 73 74 frame = (struct rt_sigframe_n32 __user *) regs.regs[29]; 75 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 76 goto badframe; 77 if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask)) 78 goto badframe; 79 80 set_current_blocked(&set); 81 82 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext); 83 if (sig < 0) 84 goto badframe; 85 else if (sig) 86 force_sig(sig, current); 87 88 if (compat_restore_altstack(&frame->rs_uc.uc_stack)) 89 goto badframe; 90 91 /* 92 * Don't let your children do this ... 93 */ 94 __asm__ __volatile__( 95 "move\t$29, %0\n\t" 96 "j\tsyscall_exit" 97 :/* no outputs */ 98 :"r" (®s)); 99 /* Unreached */ 100 101 badframe: 102 force_sig(SIGSEGV, current); 103 } 104 105 static int setup_rt_frame_n32(void *sig_return, struct ksignal *ksig, 106 struct pt_regs *regs, sigset_t *set) 107 { 108 struct rt_sigframe_n32 __user *frame; 109 int err = 0; 110 111 frame = get_sigframe(ksig, regs, sizeof(*frame)); 112 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) 113 return -EFAULT; 114 115 /* Create siginfo. */ 116 err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info); 117 118 /* Create the ucontext. */ 119 err |= __put_user(0, &frame->rs_uc.uc_flags); 120 err |= __put_user(0, &frame->rs_uc.uc_link); 121 err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]); 122 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext); 123 err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set); 124 125 if (err) 126 return -EFAULT; 127 128 /* 129 * Arguments to signal handler: 130 * 131 * a0 = signal number 132 * a1 = 0 (should be cause) 133 * a2 = pointer to ucontext 134 * 135 * $25 and c0_epc point to the signal handler, $29 points to 136 * the struct rt_sigframe. 137 */ 138 regs->regs[ 4] = ksig->sig; 139 regs->regs[ 5] = (unsigned long) &frame->rs_info; 140 regs->regs[ 6] = (unsigned long) &frame->rs_uc; 141 regs->regs[29] = (unsigned long) frame; 142 regs->regs[31] = (unsigned long) sig_return; 143 regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; 144 145 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", 146 current->comm, current->pid, 147 frame, regs->cp0_epc, regs->regs[31]); 148 149 return 0; 150 } 151 152 struct mips_abi mips_abi_n32 = { 153 .setup_rt_frame = setup_rt_frame_n32, 154 .rt_signal_return_offset = 155 offsetof(struct mips_vdso, n32_rt_signal_trampoline), 156 .restart = __NR_N32_restart_syscall, 157 158 .off_sc_fpregs = offsetof(struct sigcontext, sc_fpregs), 159 .off_sc_fpc_csr = offsetof(struct sigcontext, sc_fpc_csr), 160 .off_sc_used_math = offsetof(struct sigcontext, sc_used_math), 161 }; 162