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 <linux/uaccess.h> 37 #include <asm/ucontext.h> 38 #include <asm/fpu.h> 39 #include <asm/cpu-features.h> 40 #include <asm/war.h> 41 42 #include "signal-common.h" 43 44 /* 45 * Including <asm/unistd.h> would give use the 64-bit syscall numbers ... 46 */ 47 #define __NR_N32_restart_syscall 6214 48 49 extern int setup_sigcontext(struct pt_regs *, struct sigcontext __user *); 50 extern int restore_sigcontext(struct pt_regs *, struct sigcontext __user *); 51 52 struct ucontextn32 { 53 u32 uc_flags; 54 s32 uc_link; 55 compat_stack_t uc_stack; 56 struct sigcontext uc_mcontext; 57 compat_sigset_t uc_sigmask; /* mask last for extensibility */ 58 }; 59 60 struct rt_sigframe_n32 { 61 u32 rs_ass[4]; /* argument save space for o32 */ 62 u32 rs_pad[2]; /* Was: signal trampoline */ 63 struct compat_siginfo rs_info; 64 struct ucontextn32 rs_uc; 65 }; 66 67 asmlinkage void sysn32_rt_sigreturn(void) 68 { 69 struct rt_sigframe_n32 __user *frame; 70 struct pt_regs *regs; 71 sigset_t set; 72 int sig; 73 74 regs = current_pt_regs(); 75 frame = (struct rt_sigframe_n32 __user *)regs->regs[29]; 76 if (!access_ok(frame, sizeof(*frame))) 77 goto badframe; 78 if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask)) 79 goto badframe; 80 81 set_current_blocked(&set); 82 83 sig = restore_sigcontext(regs, &frame->rs_uc.uc_mcontext); 84 if (sig < 0) 85 goto badframe; 86 else if (sig) 87 force_sig(sig, current); 88 89 if (compat_restore_altstack(&frame->rs_uc.uc_stack)) 90 goto badframe; 91 92 /* 93 * Don't let your children do this ... 94 */ 95 __asm__ __volatile__( 96 "move\t$29, %0\n\t" 97 "j\tsyscall_exit" 98 : /* no outputs */ 99 : "r" (regs)); 100 /* Unreached */ 101 102 badframe: 103 force_sig(SIGSEGV, current); 104 } 105 106 static int setup_rt_frame_n32(void *sig_return, struct ksignal *ksig, 107 struct pt_regs *regs, sigset_t *set) 108 { 109 struct rt_sigframe_n32 __user *frame; 110 int err = 0; 111 112 frame = get_sigframe(ksig, regs, sizeof(*frame)); 113 if (!access_ok(frame, sizeof (*frame))) 114 return -EFAULT; 115 116 /* Create siginfo. */ 117 err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info); 118 119 /* Create the ucontext. */ 120 err |= __put_user(0, &frame->rs_uc.uc_flags); 121 err |= __put_user(0, &frame->rs_uc.uc_link); 122 err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]); 123 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext); 124 err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set); 125 126 if (err) 127 return -EFAULT; 128 129 /* 130 * Arguments to signal handler: 131 * 132 * a0 = signal number 133 * a1 = 0 (should be cause) 134 * a2 = pointer to ucontext 135 * 136 * $25 and c0_epc point to the signal handler, $29 points to 137 * the struct rt_sigframe. 138 */ 139 regs->regs[ 4] = ksig->sig; 140 regs->regs[ 5] = (unsigned long) &frame->rs_info; 141 regs->regs[ 6] = (unsigned long) &frame->rs_uc; 142 regs->regs[29] = (unsigned long) frame; 143 regs->regs[31] = (unsigned long) sig_return; 144 regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; 145 146 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", 147 current->comm, current->pid, 148 frame, regs->cp0_epc, regs->regs[31]); 149 150 return 0; 151 } 152 153 struct mips_abi mips_abi_n32 = { 154 .setup_rt_frame = setup_rt_frame_n32, 155 .restart = __NR_N32_restart_syscall, 156 157 .off_sc_fpregs = offsetof(struct sigcontext, sc_fpregs), 158 .off_sc_fpc_csr = offsetof(struct sigcontext, sc_fpc_csr), 159 .off_sc_used_math = offsetof(struct sigcontext, sc_used_math), 160 161 .vdso = &vdso_image_n32, 162 }; 163