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 "user-internals.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 };
  59
  60 struct target_rt_sigframe {
  61     target_siginfo_t info;
  62     struct target_ucontext uc;
  63 };
  64
  65 #define INSN_MOV_R30_R16        0x47fe0410
  66 #define INSN_LDI_R0             0x201f0000
  67 #define INSN_CALLSYS            0x00000083
  68
  69 static void setup_sigcontext(struct target_sigcontext *sc, CPUAlphaState *env,
  70                              abi_ulong frame_addr, target_sigset_t *set)
  71 {
  72     int i;
  73
  74     __put_user(on_sig_stack(frame_addr), &sc->sc_onstack);
  75     __put_user(set->sig[0], &sc->sc_mask);
  76     __put_user(env->pc, &sc->sc_pc);
  77     __put_user(8, &sc->sc_ps);
  78
  79     for (i = 0; i < 31; ++i) {
  80         __put_user(env->ir[i], &sc->sc_regs[i]);
  81     }
  82     __put_user(0, &sc->sc_regs[31]);
  83
  84     for (i = 0; i < 31; ++i) {
  85         __put_user(env->fir[i], &sc->sc_fpregs[i]);
  86     }
  87     __put_user(0, &sc->sc_fpregs[31]);
  88     __put_user(cpu_alpha_load_fpcr(env), &sc->sc_fpcr);
  89
  90     __put_user(0, &sc->sc_traparg_a0); /* FIXME */
  91     __put_user(0, &sc->sc_traparg_a1); /* FIXME */
  92     __put_user(0, &sc->sc_traparg_a2); /* FIXME */
  93 }
  94
  95 static void restore_sigcontext(CPUAlphaState *env,
  96                                struct target_sigcontext *sc)
  97 {
  98     uint64_t fpcr;
  99     int i;
 100
 101     __get_user(env->pc, &sc->sc_pc);
 102
 103     for (i = 0; i < 31; ++i) {
 104         __get_user(env->ir[i], &sc->sc_regs[i]);
 105     }
 106     for (i = 0; i < 31; ++i) {
 107         __get_user(env->fir[i], &sc->sc_fpregs[i]);
 108     }
 109
 110     __get_user(fpcr, &sc->sc_fpcr);
 111     cpu_alpha_store_fpcr(env, fpcr);
 112 }
 113
 114 static inline abi_ulong get_sigframe(struct target_sigaction *sa,
 115                                      CPUAlphaState *env,
 116                                      unsigned long framesize)
 117 {
 118     abi_ulong sp;
 119
 120     sp = target_sigsp(get_sp_from_cpustate(env), sa);
 121
 122     return (sp - framesize) & -32;
 123 }
 124
 125 void setup_frame(int sig, struct target_sigaction *ka,
 126                  target_sigset_t *set, CPUAlphaState *env)
 127 {
 128     abi_ulong frame_addr, r26;
 129     struct target_sigframe *frame;
 130     int err = 0;
 131
 132     frame_addr = get_sigframe(ka, env, sizeof(*frame));
 133     trace_user_setup_frame(env, frame_addr);
 134     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
 135         goto give_sigsegv;
 136     }
 137
 138     setup_sigcontext(&frame->sc, env, frame_addr, set);
 139
 140     if (ka->ka_restorer) {
 141         r26 = ka->ka_restorer;
 142     } else {
 143         r26 = default_sigreturn;
 144     }
 145
 146     unlock_user_struct(frame, frame_addr, 1);
 147
 148     if (err) {
 149 give_sigsegv:
 150         force_sigsegv(sig);
 151         return;
 152     }
 153
 154     env->ir[IR_RA] = r26;
 155     env->ir[IR_PV] = env->pc = ka->_sa_handler;
 156     env->ir[IR_A0] = sig;
 157     env->ir[IR_A1] = 0;
 158     env->ir[IR_A2] = frame_addr + offsetof(struct target_sigframe, sc);
 159     env->ir[IR_SP] = frame_addr;
 160 }
 161
 162 void setup_rt_frame(int sig, struct target_sigaction *ka,
 163                     target_siginfo_t *info,
 164                     target_sigset_t *set, CPUAlphaState *env)
 165 {
 166     abi_ulong frame_addr, r26;
 167     struct target_rt_sigframe *frame;
 168     int i, err = 0;
 169
 170     frame_addr = get_sigframe(ka, env, sizeof(*frame));
 171     trace_user_setup_rt_frame(env, frame_addr);
 172     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
 173         goto give_sigsegv;
 174     }
 175
 176     tswap_siginfo(&frame->info, info);
 177
 178     __put_user(0, &frame->uc.tuc_flags);
 179     __put_user(0, &frame->uc.tuc_link);
 180     __put_user(set->sig[0], &frame->uc.tuc_osf_sigmask);
 181
 182     target_save_altstack(&frame->uc.tuc_stack, env);
 183
 184     setup_sigcontext(&frame->uc.tuc_mcontext, env, frame_addr, set);
 185     for (i = 0; i < TARGET_NSIG_WORDS; ++i) {
 186         __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
 187     }
 188
 189     if (ka->ka_restorer) {
 190         r26 = ka->ka_restorer;
 191     } else {
 192         r26 = default_rt_sigreturn;
 193     }
 194
 195     if (err) {
 196 give_sigsegv:
 197         force_sigsegv(sig);
 198         return;
 199     }
 200
 201     env->ir[IR_RA] = r26;
 202     env->ir[IR_PV] = env->pc = ka->_sa_handler;
 203     env->ir[IR_A0] = sig;
 204     env->ir[IR_A1] = frame_addr + offsetof(struct target_rt_sigframe, info);
 205     env->ir[IR_A2] = frame_addr + offsetof(struct target_rt_sigframe, uc);
 206     env->ir[IR_SP] = frame_addr;
 207 }
 208
 209 long do_sigreturn(CPUAlphaState *env)
 210 {
 211     struct target_sigcontext *sc;
 212     abi_ulong sc_addr = env->ir[IR_A0];
 213     target_sigset_t target_set;
 214     sigset_t set;
 215
 216     if (!lock_user_struct(VERIFY_READ, sc, sc_addr, 1)) {
 217         goto badframe;
 218     }
 219
 220     target_sigemptyset(&target_set);
 221     __get_user(target_set.sig[0], &sc->sc_mask);
 222
 223     target_to_host_sigset_internal(&set, &target_set);
 224     set_sigmask(&set);
 225
 226     restore_sigcontext(env, sc);
 227     unlock_user_struct(sc, sc_addr, 0);
 228     return -QEMU_ESIGRETURN;
 229
 230 badframe:
 231     force_sig(TARGET_SIGSEGV);
 232     return -QEMU_ESIGRETURN;
 233 }
 234
 235 long do_rt_sigreturn(CPUAlphaState *env)
 236 {
 237     abi_ulong frame_addr = env->ir[IR_A0];
 238     struct target_rt_sigframe *frame;
 239     sigset_t set;
 240
 241     trace_user_do_rt_sigreturn(env, frame_addr);
 242     if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
 243         goto badframe;
 244     }
 245     target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
 246     set_sigmask(&set);
 247
 248     restore_sigcontext(env, &frame->uc.tuc_mcontext);
 249     target_restore_altstack(&frame->uc.tuc_stack, env);
 250
 251     unlock_user_struct(frame, frame_addr, 0);
 252     return -QEMU_ESIGRETURN;
 253
 254
 255 badframe:
 256     unlock_user_struct(frame, frame_addr, 0);
 257     force_sig(TARGET_SIGSEGV);
 258     return -QEMU_ESIGRETURN;
 259 }
 260
 261 void setup_sigtramp(abi_ulong sigtramp_page)
 262 {
 263     uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 6 * 4, 0);
 264     assert(tramp != NULL);
 265
 266     default_sigreturn = sigtramp_page;
 267     __put_user(INSN_MOV_R30_R16, &tramp[0]);
 268     __put_user(INSN_LDI_R0 + TARGET_NR_sigreturn, &tramp[1]);
 269     __put_user(INSN_CALLSYS, &tramp[2]);
 270
 271     default_rt_sigreturn = sigtramp_page + 3 * 4;
 272     __put_user(INSN_MOV_R30_R16, &tramp[3]);
 273     __put_user(INSN_LDI_R0 + TARGET_NR_rt_sigreturn, &tramp[4]);
 274     __put_user(INSN_CALLSYS, &tramp[5]);
 275
 276     unlock_user(tramp, sigtramp_page, 6 * 4);
 277 }