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 "signal-common.h"
  22 #include "linux-user/trace.h"
  23
  24 struct target_sigcontext {
  25     abi_long sc_onstack;
  26     abi_long sc_mask;
  27     abi_long sc_pc;
  28     abi_long sc_ps;
  29     abi_long sc_regs[32];
  30     abi_long sc_ownedfp;
  31     abi_long sc_fpregs[32];
  32     abi_ulong sc_fpcr;
  33     abi_ulong sc_fp_control;
  34     abi_ulong sc_reserved1;
  35     abi_ulong sc_reserved2;
  36     abi_ulong sc_ssize;
  37     abi_ulong sc_sbase;
  38     abi_ulong sc_traparg_a0;
  39     abi_ulong sc_traparg_a1;
  40     abi_ulong sc_traparg_a2;
  41     abi_ulong sc_fp_trap_pc;
  42     abi_ulong sc_fp_trigger_sum;
  43     abi_ulong sc_fp_trigger_inst;
  44 };
  45
  46 struct target_ucontext {
  47     abi_ulong tuc_flags;
  48     abi_ulong tuc_link;
  49     abi_ulong tuc_osf_sigmask;
  50     target_stack_t tuc_stack;
  51     struct target_sigcontext tuc_mcontext;
  52     target_sigset_t tuc_sigmask;
  53 };
  54
  55 struct target_sigframe {
  56     struct target_sigcontext sc;
  57     unsigned int retcode[3];
  58 };
  59
  60 struct target_rt_sigframe {
  61     target_siginfo_t info;
  62     struct target_ucontext uc;
  63     unsigned int retcode[3];
  64 };
  65
  66 #define INSN_MOV_R30_R16        0x47fe0410
  67 #define INSN_LDI_R0             0x201f0000
  68 #define INSN_CALLSYS            0x00000083
  69
  70 static void setup_sigcontext(struct target_sigcontext *sc, CPUAlphaState *env,
  71                              abi_ulong frame_addr, target_sigset_t *set)
  72 {
  73     int i;
  74
  75     __put_user(on_sig_stack(frame_addr), &sc->sc_onstack);
  76     __put_user(set->sig[0], &sc->sc_mask);
  77     __put_user(env->pc, &sc->sc_pc);
  78     __put_user(8, &sc->sc_ps);
  79
  80     for (i = 0; i < 31; ++i) {
  81         __put_user(env->ir[i], &sc->sc_regs[i]);
  82     }
  83     __put_user(0, &sc->sc_regs[31]);
  84
  85     for (i = 0; i < 31; ++i) {
  86         __put_user(env->fir[i], &sc->sc_fpregs[i]);
  87     }
  88     __put_user(0, &sc->sc_fpregs[31]);
  89     __put_user(cpu_alpha_load_fpcr(env), &sc->sc_fpcr);
  90
  91     __put_user(0, &sc->sc_traparg_a0); /* FIXME */
  92     __put_user(0, &sc->sc_traparg_a1); /* FIXME */
  93     __put_user(0, &sc->sc_traparg_a2); /* FIXME */
  94 }
  95
  96 static void restore_sigcontext(CPUAlphaState *env,
  97                                struct target_sigcontext *sc)
  98 {
  99     uint64_t fpcr;
 100     int i;
 101
 102     __get_user(env->pc, &sc->sc_pc);
 103
 104     for (i = 0; i < 31; ++i) {
 105         __get_user(env->ir[i], &sc->sc_regs[i]);
 106     }
 107     for (i = 0; i < 31; ++i) {
 108         __get_user(env->fir[i], &sc->sc_fpregs[i]);
 109     }
 110
 111     __get_user(fpcr, &sc->sc_fpcr);
 112     cpu_alpha_store_fpcr(env, fpcr);
 113 }
 114
 115 static inline abi_ulong get_sigframe(struct target_sigaction *sa,
 116                                      CPUAlphaState *env,
 117                                      unsigned long framesize)
 118 {
 119     abi_ulong sp;
 120
 121     sp = target_sigsp(get_sp_from_cpustate(env), sa);
 122
 123     return (sp - framesize) & -32;
 124 }
 125
 126 void setup_frame(int sig, struct target_sigaction *ka,
 127                  target_sigset_t *set, CPUAlphaState *env)
 128 {
 129     abi_ulong frame_addr, r26;
 130     struct target_sigframe *frame;
 131     int err = 0;
 132
 133     frame_addr = get_sigframe(ka, env, sizeof(*frame));
 134     trace_user_setup_frame(env, frame_addr);
 135     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
 136         goto give_sigsegv;
 137     }
 138
 139     setup_sigcontext(&frame->sc, env, frame_addr, set);
 140
 141     if (ka->sa_restorer) {
 142         r26 = ka->sa_restorer;
 143     } else {
 144         __put_user(INSN_MOV_R30_R16, &frame->retcode[0]);
 145         __put_user(INSN_LDI_R0 + TARGET_NR_sigreturn,
 146                    &frame->retcode[1]);
 147         __put_user(INSN_CALLSYS, &frame->retcode[2]);
 148         /* imb() */
 149         r26 = frame_addr + offsetof(struct target_sigframe, retcode);
 150     }
 151
 152     unlock_user_struct(frame, frame_addr, 1);
 153
 154     if (err) {
 155 give_sigsegv:
 156         force_sigsegv(sig);
 157         return;
 158     }
 159
 160     env->ir[IR_RA] = r26;
 161     env->ir[IR_PV] = env->pc = ka->_sa_handler;
 162     env->ir[IR_A0] = sig;
 163     env->ir[IR_A1] = 0;
 164     env->ir[IR_A2] = frame_addr + offsetof(struct target_sigframe, sc);
 165     env->ir[IR_SP] = frame_addr;
 166 }
 167
 168 void setup_rt_frame(int sig, struct target_sigaction *ka,
 169                     target_siginfo_t *info,
 170                     target_sigset_t *set, CPUAlphaState *env)
 171 {
 172     abi_ulong frame_addr, r26;
 173     struct target_rt_sigframe *frame;
 174     int i, err = 0;
 175
 176     frame_addr = get_sigframe(ka, env, sizeof(*frame));
 177     trace_user_setup_rt_frame(env, frame_addr);
 178     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
 179         goto give_sigsegv;
 180     }
 181
 182     tswap_siginfo(&frame->info, info);
 183
 184     __put_user(0, &frame->uc.tuc_flags);
 185     __put_user(0, &frame->uc.tuc_link);
 186     __put_user(set->sig[0], &frame->uc.tuc_osf_sigmask);
 187
 188     target_save_altstack(&frame->uc.tuc_stack, env);
 189
 190     setup_sigcontext(&frame->uc.tuc_mcontext, env, frame_addr, set);
 191     for (i = 0; i < TARGET_NSIG_WORDS; ++i) {
 192         __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
 193     }
 194
 195     if (ka->sa_restorer) {
 196         r26 = ka->sa_restorer;
 197     } else {
 198         __put_user(INSN_MOV_R30_R16, &frame->retcode[0]);
 199         __put_user(INSN_LDI_R0 + TARGET_NR_rt_sigreturn,
 200                    &frame->retcode[1]);
 201         __put_user(INSN_CALLSYS, &frame->retcode[2]);
 202         /* imb(); */
 203         r26 = frame_addr + offsetof(struct target_sigframe, retcode);
 204     }
 205
 206     if (err) {
 207 give_sigsegv:
 208         force_sigsegv(sig);
 209         return;
 210     }
 211
 212     env->ir[IR_RA] = r26;
 213     env->ir[IR_PV] = env->pc = ka->_sa_handler;
 214     env->ir[IR_A0] = sig;
 215     env->ir[IR_A1] = frame_addr + offsetof(struct target_rt_sigframe, info);
 216     env->ir[IR_A2] = frame_addr + offsetof(struct target_rt_sigframe, uc);
 217     env->ir[IR_SP] = frame_addr;
 218 }
 219
 220 long do_sigreturn(CPUAlphaState *env)
 221 {
 222     struct target_sigcontext *sc;
 223     abi_ulong sc_addr = env->ir[IR_A0];
 224     target_sigset_t target_set;
 225     sigset_t set;
 226
 227     if (!lock_user_struct(VERIFY_READ, sc, sc_addr, 1)) {
 228         goto badframe;
 229     }
 230
 231     target_sigemptyset(&target_set);
 232     __get_user(target_set.sig[0], &sc->sc_mask);
 233
 234     target_to_host_sigset_internal(&set, &target_set);
 235     set_sigmask(&set);
 236
 237     restore_sigcontext(env, sc);
 238     unlock_user_struct(sc, sc_addr, 0);
 239     return -TARGET_QEMU_ESIGRETURN;
 240
 241 badframe:
 242     force_sig(TARGET_SIGSEGV);
 243     return -TARGET_QEMU_ESIGRETURN;
 244 }
 245
 246 long do_rt_sigreturn(CPUAlphaState *env)
 247 {
 248     abi_ulong frame_addr = env->ir[IR_A0];
 249     struct target_rt_sigframe *frame;
 250     sigset_t set;
 251
 252     trace_user_do_rt_sigreturn(env, frame_addr);
 253     if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
 254         goto badframe;
 255     }
 256     target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
 257     set_sigmask(&set);
 258
 259     restore_sigcontext(env, &frame->uc.tuc_mcontext);
 260     if (do_sigaltstack(frame_addr + offsetof(struct target_rt_sigframe,
 261                                              uc.tuc_stack),
 262                        0, env->ir[IR_SP]) == -EFAULT) {
 263         goto badframe;
 264     }
 265
 266     unlock_user_struct(frame, frame_addr, 0);
 267     return -TARGET_QEMU_ESIGRETURN;
 268
 269
 270 badframe:
 271     unlock_user_struct(frame, frame_addr, 0);
 272     force_sig(TARGET_SIGSEGV);
 273     return -TARGET_QEMU_ESIGRETURN;
 274 }