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/sched.h> 19 #include <linux/mm.h> 20 #include <linux/smp.h> 21 #include <linux/smp_lock.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/asm.h> 32 #include <asm/cacheflush.h> 33 #include <asm/sim.h> 34 #include <asm/uaccess.h> 35 #include <asm/ucontext.h> 36 #include <asm/system.h> 37 #include <asm/fpu.h> 38 #include <asm/cpu-features.h> 39 40 #include "signal-common.h" 41 42 /* 43 * Including <asm/unistd.h> would give use the 64-bit syscall numbers ... 44 */ 45 #define __NR_N32_rt_sigreturn 6211 46 #define __NR_N32_restart_syscall 6214 47 48 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) 49 50 /* IRIX compatible stack_t */ 51 typedef struct sigaltstack32 { 52 s32 ss_sp; 53 compat_size_t ss_size; 54 int ss_flags; 55 } stack32_t; 56 57 struct ucontextn32 { 58 u32 uc_flags; 59 s32 uc_link; 60 stack32_t uc_stack; 61 struct sigcontext uc_mcontext; 62 sigset_t uc_sigmask; /* mask last for extensibility */ 63 }; 64 65 #if PLAT_TRAMPOLINE_STUFF_LINE 66 #define __tramp __attribute__((aligned(PLAT_TRAMPOLINE_STUFF_LINE))) 67 #else 68 #define __tramp 69 #endif 70 71 struct rt_sigframe_n32 { 72 u32 rs_ass[4]; /* argument save space for o32 */ 73 u32 rs_code[2] __tramp; /* signal trampoline */ 74 struct siginfo rs_info __tramp; 75 struct ucontextn32 rs_uc; 76 }; 77 78 save_static_function(sysn32_rt_sigreturn); 79 __attribute_used__ noinline static void 80 _sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs) 81 { 82 struct rt_sigframe_n32 *frame; 83 sigset_t set; 84 stack_t st; 85 s32 sp; 86 87 frame = (struct rt_sigframe_n32 *) regs.regs[29]; 88 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 89 goto badframe; 90 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set))) 91 goto badframe; 92 93 sigdelsetmask(&set, ~_BLOCKABLE); 94 spin_lock_irq(¤t->sighand->siglock); 95 current->blocked = set; 96 recalc_sigpending(); 97 spin_unlock_irq(¤t->sighand->siglock); 98 99 if (restore_sigcontext(®s, &frame->rs_uc.uc_mcontext)) 100 goto badframe; 101 102 /* The ucontext contains a stack32_t, so we must convert! */ 103 if (__get_user(sp, &frame->rs_uc.uc_stack.ss_sp)) 104 goto badframe; 105 st.ss_size = (long) sp; 106 if (__get_user(st.ss_size, &frame->rs_uc.uc_stack.ss_size)) 107 goto badframe; 108 if (__get_user(st.ss_flags, &frame->rs_uc.uc_stack.ss_flags)) 109 goto badframe; 110 111 /* It is more difficult to avoid calling this function than to 112 call it and ignore errors. */ 113 do_sigaltstack(&st, NULL, regs.regs[29]); 114 115 /* 116 * Don't let your children do this ... 117 */ 118 __asm__ __volatile__( 119 "move\t$29, %0\n\t" 120 "j\tsyscall_exit" 121 :/* no outputs */ 122 :"r" (®s)); 123 /* Unreached */ 124 125 badframe: 126 force_sig(SIGSEGV, current); 127 } 128 129 void setup_rt_frame_n32(struct k_sigaction * ka, 130 struct pt_regs *regs, int signr, sigset_t *set, siginfo_t *info) 131 { 132 struct rt_sigframe_n32 *frame; 133 int err = 0; 134 s32 sp; 135 136 frame = get_sigframe(ka, regs, sizeof(*frame)); 137 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) 138 goto give_sigsegv; 139 140 /* 141 * Set up the return code ... 142 * 143 * li v0, __NR_rt_sigreturn 144 * syscall 145 */ 146 if (PLAT_TRAMPOLINE_STUFF_LINE) 147 __clear_user(frame->rs_code, PLAT_TRAMPOLINE_STUFF_LINE); 148 err |= __put_user(0x24020000 + __NR_N32_rt_sigreturn, frame->rs_code + 0); 149 err |= __put_user(0x0000000c , frame->rs_code + 1); 150 flush_cache_sigtramp((unsigned long) frame->rs_code); 151 152 /* Create siginfo. */ 153 err |= copy_siginfo_to_user(&frame->rs_info, info); 154 155 /* Create the ucontext. */ 156 err |= __put_user(0, &frame->rs_uc.uc_flags); 157 err |= __put_user(0, &frame->rs_uc.uc_link); 158 sp = (int) (long) current->sas_ss_sp; 159 err |= __put_user(sp, 160 &frame->rs_uc.uc_stack.ss_sp); 161 err |= __put_user(sas_ss_flags(regs->regs[29]), 162 &frame->rs_uc.uc_stack.ss_flags); 163 err |= __put_user(current->sas_ss_size, 164 &frame->rs_uc.uc_stack.ss_size); 165 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext); 166 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set)); 167 168 if (err) 169 goto give_sigsegv; 170 171 /* 172 * Arguments to signal handler: 173 * 174 * a0 = signal number 175 * a1 = 0 (should be cause) 176 * a2 = pointer to ucontext 177 * 178 * $25 and c0_epc point to the signal handler, $29 points to 179 * the struct rt_sigframe. 180 */ 181 regs->regs[ 4] = signr; 182 regs->regs[ 5] = (unsigned long) &frame->rs_info; 183 regs->regs[ 6] = (unsigned long) &frame->rs_uc; 184 regs->regs[29] = (unsigned long) frame; 185 regs->regs[31] = (unsigned long) frame->rs_code; 186 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler; 187 188 #if DEBUG_SIG 189 printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n", 190 current->comm, current->pid, 191 frame, regs->cp0_epc, regs->regs[31]); 192 #endif 193 return; 194 195 give_sigsegv: 196 force_sigsegv(signr, current); 197 } 198