linux-user/microblaze/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     struct target_pt_regs regs;  /* needs to be first */
  26     uint32_t oldmask;
  27 };
  28
  29 struct target_stack_t {
  30     abi_ulong ss_sp;
  31     int ss_flags;
  32     unsigned int ss_size;
  33 };
  34
  35 struct target_ucontext {
  36     abi_ulong tuc_flags;
  37     abi_ulong tuc_link;
  38     target_stack_t tuc_stack;
  39     struct target_sigcontext tuc_mcontext;
  40     target_sigset_t tuc_sigmask;
  41 };
  42
  43 /* Signal frames. */
  44 struct target_rt_sigframe {
  45     target_siginfo_t info;
  46     struct target_ucontext uc;
  47     uint32_t tramp[2];
  48 };
  49
  50 static void setup_sigcontext(struct target_sigcontext *sc, CPUMBState *env)
  51 {
  52     __put_user(env->regs[0], &sc->regs.r0);
  53     __put_user(env->regs[1], &sc->regs.r1);
  54     __put_user(env->regs[2], &sc->regs.r2);
  55     __put_user(env->regs[3], &sc->regs.r3);
  56     __put_user(env->regs[4], &sc->regs.r4);
  57     __put_user(env->regs[5], &sc->regs.r5);
  58     __put_user(env->regs[6], &sc->regs.r6);
  59     __put_user(env->regs[7], &sc->regs.r7);
  60     __put_user(env->regs[8], &sc->regs.r8);
  61     __put_user(env->regs[9], &sc->regs.r9);
  62     __put_user(env->regs[10], &sc->regs.r10);
  63     __put_user(env->regs[11], &sc->regs.r11);
  64     __put_user(env->regs[12], &sc->regs.r12);
  65     __put_user(env->regs[13], &sc->regs.r13);
  66     __put_user(env->regs[14], &sc->regs.r14);
  67     __put_user(env->regs[15], &sc->regs.r15);
  68     __put_user(env->regs[16], &sc->regs.r16);
  69     __put_user(env->regs[17], &sc->regs.r17);
  70     __put_user(env->regs[18], &sc->regs.r18);
  71     __put_user(env->regs[19], &sc->regs.r19);
  72     __put_user(env->regs[20], &sc->regs.r20);
  73     __put_user(env->regs[21], &sc->regs.r21);
  74     __put_user(env->regs[22], &sc->regs.r22);
  75     __put_user(env->regs[23], &sc->regs.r23);
  76     __put_user(env->regs[24], &sc->regs.r24);
  77     __put_user(env->regs[25], &sc->regs.r25);
  78     __put_user(env->regs[26], &sc->regs.r26);
  79     __put_user(env->regs[27], &sc->regs.r27);
  80     __put_user(env->regs[28], &sc->regs.r28);
  81     __put_user(env->regs[29], &sc->regs.r29);
  82     __put_user(env->regs[30], &sc->regs.r30);
  83     __put_user(env->regs[31], &sc->regs.r31);
  84     __put_user(env->pc, &sc->regs.pc);
  85 }
  86
  87 static void restore_sigcontext(struct target_sigcontext *sc, CPUMBState *env)
  88 {
  89     __get_user(env->regs[0], &sc->regs.r0);
  90     __get_user(env->regs[1], &sc->regs.r1);
  91     __get_user(env->regs[2], &sc->regs.r2);
  92     __get_user(env->regs[3], &sc->regs.r3);
  93     __get_user(env->regs[4], &sc->regs.r4);
  94     __get_user(env->regs[5], &sc->regs.r5);
  95     __get_user(env->regs[6], &sc->regs.r6);
  96     __get_user(env->regs[7], &sc->regs.r7);
  97     __get_user(env->regs[8], &sc->regs.r8);
  98     __get_user(env->regs[9], &sc->regs.r9);
  99     __get_user(env->regs[10], &sc->regs.r10);
 100     __get_user(env->regs[11], &sc->regs.r11);
 101     __get_user(env->regs[12], &sc->regs.r12);
 102     __get_user(env->regs[13], &sc->regs.r13);
 103     __get_user(env->regs[14], &sc->regs.r14);
 104     __get_user(env->regs[15], &sc->regs.r15);
 105     __get_user(env->regs[16], &sc->regs.r16);
 106     __get_user(env->regs[17], &sc->regs.r17);
 107     __get_user(env->regs[18], &sc->regs.r18);
 108     __get_user(env->regs[19], &sc->regs.r19);
 109     __get_user(env->regs[20], &sc->regs.r20);
 110     __get_user(env->regs[21], &sc->regs.r21);
 111     __get_user(env->regs[22], &sc->regs.r22);
 112     __get_user(env->regs[23], &sc->regs.r23);
 113     __get_user(env->regs[24], &sc->regs.r24);
 114     __get_user(env->regs[25], &sc->regs.r25);
 115     __get_user(env->regs[26], &sc->regs.r26);
 116     __get_user(env->regs[27], &sc->regs.r27);
 117     __get_user(env->regs[28], &sc->regs.r28);
 118     __get_user(env->regs[29], &sc->regs.r29);
 119     __get_user(env->regs[30], &sc->regs.r30);
 120     __get_user(env->regs[31], &sc->regs.r31);
 121     __get_user(env->pc, &sc->regs.pc);
 122 }
 123
 124 static abi_ulong get_sigframe(struct target_sigaction *ka,
 125                               CPUMBState *env, int frame_size)
 126 {
 127     abi_ulong sp = env->regs[1];
 128
 129     sp = target_sigsp(sp, ka);
 130
 131     return ((sp - frame_size) & -8UL);
 132 }
 133
 134 void setup_rt_frame(int sig, struct target_sigaction *ka,
 135                     target_siginfo_t *info,
 136                     target_sigset_t *set, CPUMBState *env)
 137 {
 138     struct target_rt_sigframe *frame;
 139     abi_ulong frame_addr;
 140
 141     frame_addr = get_sigframe(ka, env, sizeof *frame);
 142     trace_user_setup_rt_frame(env, frame_addr);
 143
 144     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
 145         force_sigsegv(sig);
 146         return;
 147     }
 148
 149     tswap_siginfo(&frame->info, info);
 150
 151     __put_user(0, &frame->uc.tuc_flags);
 152     __put_user(0, &frame->uc.tuc_link);
 153
 154     target_save_altstack(&frame->uc.tuc_stack, env);
 155     setup_sigcontext(&frame->uc.tuc_mcontext, env);
 156
 157     for (int i = 0; i < TARGET_NSIG_WORDS; i++) {
 158         __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
 159     }
 160
 161     /* Kernel does not use SA_RESTORER. */
 162
 163     /* addi r12, r0, __NR_sigreturn */
 164     __put_user(0x31800000U | TARGET_NR_rt_sigreturn, frame->tramp + 0);
 165     /* brki r14, 0x8 */
 166     __put_user(0xb9cc0008U, frame->tramp + 1);
 167
 168     /*
 169      * Return from sighandler will jump to the tramp.
 170      * Negative 8 offset because return is rtsd r15, 8
 171      */
 172     env->regs[15] =
 173         frame_addr + offsetof(struct target_rt_sigframe, tramp) - 8;
 174
 175     /* Set up registers for signal handler */
 176     env->regs[1] = frame_addr;
 177
 178     /* Signal handler args: */
 179     env->regs[5] = sig;
 180     env->regs[6] = frame_addr + offsetof(struct target_rt_sigframe, info);
 181     env->regs[7] = frame_addr + offsetof(struct target_rt_sigframe, uc);
 182
 183     /* Offset to handle microblaze rtid r14, 0 */
 184     env->pc = (unsigned long)ka->_sa_handler;
 185
 186     unlock_user_struct(frame, frame_addr, 1);
 187 }
 188
 189
 190 long do_sigreturn(CPUMBState *env)
 191 {
 192     return -TARGET_ENOSYS;
 193 }
 194
 195 long do_rt_sigreturn(CPUMBState *env)
 196 {
 197     struct target_rt_sigframe *frame = NULL;
 198     abi_ulong frame_addr = env->regs[1];
 199     sigset_t set;
 200
 201     trace_user_do_rt_sigreturn(env, frame_addr);
 202
 203     if  (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
 204         goto badframe;
 205     }
 206
 207     target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
 208     set_sigmask(&set);
 209
 210     restore_sigcontext(&frame->uc.tuc_mcontext, env);
 211
 212     if (do_sigaltstack(frame_addr +
 213                        offsetof(struct target_rt_sigframe, uc.tuc_stack),
 214                        0, get_sp_from_cpustate(env)) == -EFAULT) {
 215         goto badframe;
 216     }
 217
 218     unlock_user_struct(frame, frame_addr, 0);
 219     return -TARGET_QEMU_ESIGRETURN;
 220
 221  badframe:
 222     unlock_user_struct(frame, frame_addr, 0);
 223     force_sig(TARGET_SIGSEGV);
 224     return -TARGET_QEMU_ESIGRETURN;
 225 }