linux-user/alpha/signal.c

   1 /*
   2  *  Emulation of Linux signals
   3  *
   4  *  Copyright (c) 2003 Fabrice Bellard
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19 #include "qemu/osdep.h"
  20 #include "qemu.h"
  21 #include "target_signal.h"
  22 #include "signal-common.h"
  23 #include "linux-user/trace.h"
  24
  25 struct target_sigcontext {
  26     abi_long sc_onstack;
  27     abi_long sc_mask;
  28     abi_long sc_pc;
  29     abi_long sc_ps;
  30     abi_long sc_regs[32];
  31     abi_long sc_ownedfp;
  32     abi_long sc_fpregs[32];
  33     abi_ulong sc_fpcr;
  34     abi_ulong sc_fp_control;
  35     abi_ulong sc_reserved1;
  36     abi_ulong sc_reserved2;
  37     abi_ulong sc_ssize;
  38     abi_ulong sc_sbase;
  39     abi_ulong sc_traparg_a0;
  40     abi_ulong sc_traparg_a1;
  41     abi_ulong sc_traparg_a2;
  42     abi_ulong sc_fp_trap_pc;
  43     abi_ulong sc_fp_trigger_sum;
  44     abi_ulong sc_fp_trigger_inst;
  45 };
  46
  47 struct target_ucontext {
  48     abi_ulong tuc_flags;
  49     abi_ulong tuc_link;
  50     abi_ulong tuc_osf_sigmask;
  51     target_stack_t tuc_stack;
  52     struct target_sigcontext tuc_mcontext;
  53     target_sigset_t tuc_sigmask;
  54 };
  55
  56 struct target_sigframe {
  57     struct target_sigcontext sc;
  58     unsigned int retcode[3];
  59 };
  60
  61 struct target_rt_sigframe {
  62     target_siginfo_t info;
  63     struct target_ucontext uc;
  64     unsigned int retcode[3];
  65 };
  66
  67 #define INSN_MOV_R30_R16        0x47fe0410
  68 #define INSN_LDI_R0             0x201f0000
  69 #define INSN_CALLSYS            0x00000083
  70
  71 static void setup_sigcontext(struct target_sigcontext *sc, CPUAlphaState *env,
  72                              abi_ulong frame_addr, target_sigset_t *set)
  73 {
  74     int i;
  75
  76     __put_user(on_sig_stack(frame_addr), &sc->sc_onstack);
  77     __put_user(set->sig[0], &sc->sc_mask);
  78     __put_user(env->pc, &sc->sc_pc);
  79     __put_user(8, &sc->sc_ps);
  80
  81     for (i = 0; i < 31; ++i) {
  82         __put_user(env->ir[i], &sc->sc_regs[i]);
  83     }
  84     __put_user(0, &sc->sc_regs[31]);
  85
  86     for (i = 0; i < 31; ++i) {
  87         __put_user(env->fir[i], &sc->sc_fpregs[i]);
  88     }
  89     __put_user(0, &sc->sc_fpregs[31]);
  90     __put_user(cpu_alpha_load_fpcr(env), &sc->sc_fpcr);
  91
  92     __put_user(0, &sc->sc_traparg_a0); /* FIXME */
  93     __put_user(0, &sc->sc_traparg_a1); /* FIXME */
  94     __put_user(0, &sc->sc_traparg_a2); /* FIXME */
  95 }
  96
  97 static void restore_sigcontext(CPUAlphaState *env,
  98                                struct target_sigcontext *sc)
  99 {
 100     uint64_t fpcr;
 101     int i;
 102
 103     __get_user(env->pc, &sc->sc_pc);
 104
 105     for (i = 0; i < 31; ++i) {
 106         __get_user(env->ir[i], &sc->sc_regs[i]);
 107     }
 108     for (i = 0; i < 31; ++i) {
 109         __get_user(env->fir[i], &sc->sc_fpregs[i]);
 110     }
 111
 112     __get_user(fpcr, &sc->sc_fpcr);
 113     cpu_alpha_store_fpcr(env, fpcr);
 114 }
 115
 116 static inline abi_ulong get_sigframe(struct target_sigaction *sa,
 117                                      CPUAlphaState *env,
 118                                      unsigned long framesize)
 119 {
 120     abi_ulong sp;
 121
 122     sp = target_sigsp(get_sp_from_cpustate(env), sa);
 123
 124     return (sp - framesize) & -32;
 125 }
 126
 127 void setup_frame(int sig, struct target_sigaction *ka,
 128                  target_sigset_t *set, CPUAlphaState *env)
 129 {
 130     abi_ulong frame_addr, r26;
 131     struct target_sigframe *frame;
 132     int err = 0;
 133
 134     frame_addr = get_sigframe(ka, env, sizeof(*frame));
 135     trace_user_setup_frame(env, frame_addr);
 136     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
 137         goto give_sigsegv;
 138     }
 139
 140     setup_sigcontext(&frame->sc, env, frame_addr, set);
 141
 142     if (ka->sa_restorer) {
 143         r26 = ka->sa_restorer;
 144     } else {
 145         __put_user(INSN_MOV_R30_R16, &frame->retcode[0]);
 146         __put_user(INSN_LDI_R0 + TARGET_NR_sigreturn,
 147                    &frame->retcode[1]);
 148         __put_user(INSN_CALLSYS, &frame->retcode[2]);
 149         /* imb() */
 150         r26 = frame_addr + offsetof(struct target_sigframe, retcode);
 151     }
 152
 153     unlock_user_struct(frame, frame_addr, 1);
 154
 155     if (err) {
 156 give_sigsegv:
 157         force_sigsegv(sig);
 158         return;
 159     }
 160
 161     env->ir[IR_RA] = r26;
 162     env->ir[IR_PV] = env->pc = ka->_sa_handler;
 163     env->ir[IR_A0] = sig;
 164     env->ir[IR_A1] = 0;
 165     env->ir[IR_A2] = frame_addr + offsetof(struct target_sigframe, sc);
 166     env->ir[IR_SP] = frame_addr;
 167 }
 168
 169 void setup_rt_frame(int sig, struct target_sigaction *ka,
 170                     target_siginfo_t *info,
 171                     target_sigset_t *set, CPUAlphaState *env)
 172 {
 173     abi_ulong frame_addr, r26;
 174     struct target_rt_sigframe *frame;
 175     int i, err = 0;
 176
 177     frame_addr = get_sigframe(ka, env, sizeof(*frame));
 178     trace_user_setup_rt_frame(env, frame_addr);
 179     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
 180         goto give_sigsegv;
 181     }
 182
 183     tswap_siginfo(&frame->info, info);
 184
 185     __put_user(0, &frame->uc.tuc_flags);
 186     __put_user(0, &frame->uc.tuc_link);
 187     __put_user(set->sig[0], &frame->uc.tuc_osf_sigmask);
 188
 189     target_save_altstack(&frame->uc.tuc_stack, env);
 190
 191     setup_sigcontext(&frame->uc.tuc_mcontext, env, frame_addr, set);
 192     for (i = 0; i < TARGET_NSIG_WORDS; ++i) {
 193         __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
 194     }
 195
 196     if (ka->sa_restorer) {
 197         r26 = ka->sa_restorer;
 198     } else {
 199         __put_user(INSN_MOV_R30_R16, &frame->retcode[0]);
 200         __put_user(INSN_LDI_R0 + TARGET_NR_rt_sigreturn,
 201                    &frame->retcode[1]);
 202         __put_user(INSN_CALLSYS, &frame->retcode[2]);
 203         /* imb(); */
 204         r26 = frame_addr + offsetof(struct target_sigframe, retcode);
 205     }
 206
 207     if (err) {
 208 give_sigsegv:
 209         force_sigsegv(sig);
 210         return;
 211     }
 212
 213     env->ir[IR_RA] = r26;
 214     env->ir[IR_PV] = env->pc = ka->_sa_handler;
 215     env->ir[IR_A0] = sig;
 216     env->ir[IR_A1] = frame_addr + offsetof(struct target_rt_sigframe, info);
 217     env->ir[IR_A2] = frame_addr + offsetof(struct target_rt_sigframe, uc);
 218     env->ir[IR_SP] = frame_addr;
 219 }
 220
 221 long do_sigreturn(CPUAlphaState *env)
 222 {
 223     struct target_sigcontext *sc;
 224     abi_ulong sc_addr = env->ir[IR_A0];
 225     target_sigset_t target_set;
 226     sigset_t set;
 227
 228     if (!lock_user_struct(VERIFY_READ, sc, sc_addr, 1)) {
 229         goto badframe;
 230     }
 231
 232     target_sigemptyset(&target_set);
 233     __get_user(target_set.sig[0], &sc->sc_mask);
 234
 235     target_to_host_sigset_internal(&set, &target_set);
 236     set_sigmask(&set);
 237
 238     restore_sigcontext(env, sc);
 239     unlock_user_struct(sc, sc_addr, 0);
 240     return -TARGET_QEMU_ESIGRETURN;
 241
 242 badframe:
 243     force_sig(TARGET_SIGSEGV);
 244     return -TARGET_QEMU_ESIGRETURN;
 245 }
 246
 247 long do_rt_sigreturn(CPUAlphaState *env)
 248 {
 249     abi_ulong frame_addr = env->ir[IR_A0];
 250     struct target_rt_sigframe *frame;
 251     sigset_t set;
 252
 253     trace_user_do_rt_sigreturn(env, frame_addr);
 254     if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
 255         goto badframe;
 256     }
 257     target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
 258     set_sigmask(&set);
 259
 260     restore_sigcontext(env, &frame->uc.tuc_mcontext);
 261     if (do_sigaltstack(frame_addr + offsetof(struct target_rt_sigframe,
 262                                              uc.tuc_stack),
 263                        0, env->ir[IR_SP]) == -EFAULT) {
 264         goto badframe;
 265     }
 266
 267     unlock_user_struct(frame, frame_addr, 0);
 268     return -TARGET_QEMU_ESIGRETURN;
 269
 270
 271 badframe:
 272     unlock_user_struct(frame, frame_addr, 0);
 273     force_sig(TARGET_SIGSEGV);
 274     return -TARGET_QEMU_ESIGRETURN;
 275 }