linux-user/sparc/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 /* A Sparc register window */
  25 struct target_reg_window {
  26     abi_ulong locals[8];
  27     abi_ulong ins[8];
  28 };
  29
  30 /* A Sparc stack frame. */
  31 struct target_stackf {
  32     /*
  33      * Since qemu does not reference fp or callers_pc directly,
  34      * it's simpler to treat fp and callers_pc as elements of ins[],
  35      * and then bundle locals[] and ins[] into reg_window.
  36      */
  37     struct target_reg_window win;
  38     /*
  39      * Similarly, bundle structptr and xxargs into xargs[].
  40      * This portion of the struct is part of the function call abi,
  41      * and belongs to the callee for spilling argument registers.
  42      */
  43     abi_ulong xargs[8];
  44 };
  45
  46 typedef struct {
  47     abi_ulong  si_float_regs[32];
  48     unsigned   long si_fsr;
  49     unsigned   long si_fpqdepth;
  50     struct {
  51         unsigned long *insn_addr;
  52         unsigned long insn;
  53     } si_fpqueue [16];
  54 } qemu_siginfo_fpu_t;
  55
  56
  57 struct target_signal_frame {
  58     struct target_stackf ss;
  59     struct target_pt_regs regs;
  60     uint32_t            si_mask;
  61     abi_ulong           fpu_save;
  62     uint32_t            insns[2] QEMU_ALIGNED(8);
  63     abi_ulong           extramask[TARGET_NSIG_WORDS - 1];
  64     abi_ulong           extra_size; /* Should be 0 */
  65     qemu_siginfo_fpu_t fpu_state;
  66 };
  67
  68 static inline abi_ulong get_sigframe(struct target_sigaction *sa,
  69                                      CPUSPARCState *env,
  70                                      unsigned long framesize)
  71 {
  72     abi_ulong sp = get_sp_from_cpustate(env);
  73
  74     /*
  75      * If we are on the alternate signal stack and would overflow it, don't.
  76      * Return an always-bogus address instead so we will die with SIGSEGV.
  77          */
  78     if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) {
  79             return -1;
  80     }
  81
  82     /* This is the X/Open sanctioned signal stack switching.  */
  83     sp = target_sigsp(sp, sa) - framesize;
  84
  85     /* Always align the stack frame.  This handles two cases.  First,
  86      * sigaltstack need not be mindful of platform specific stack
  87      * alignment.  Second, if we took this signal because the stack
  88      * is not aligned properly, we'd like to take the signal cleanly
  89      * and report that.
  90      */
  91     sp &= ~15UL;
  92
  93     return sp;
  94 }
  95
  96 static void save_pt_regs(struct target_pt_regs *regs, CPUSPARCState *env)
  97 {
  98     int i;
  99
 100 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
 101     __put_user(sparc64_tstate(env), &regs->tstate);
 102     /* TODO: magic should contain PT_REG_MAGIC + %tt. */
 103     __put_user(0, &regs->magic);
 104 #else
 105     __put_user(cpu_get_psr(env), &regs->psr);
 106 #endif
 107
 108     __put_user(env->pc, &regs->pc);
 109     __put_user(env->npc, &regs->npc);
 110     __put_user(env->y, &regs->y);
 111
 112     for (i = 0; i < 8; i++) {
 113         __put_user(env->gregs[i], &regs->u_regs[i]);
 114     }
 115     for (i = 0; i < 8; i++) {
 116         __put_user(env->regwptr[WREG_O0 + i], &regs->u_regs[i + 8]);
 117     }
 118 }
 119
 120 static void restore_pt_regs(struct target_pt_regs *regs, CPUSPARCState *env)
 121 {
 122     int i;
 123
 124 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
 125     /* User can only change condition codes and %asi in %tstate. */
 126     uint64_t tstate;
 127     __get_user(tstate, &regs->tstate);
 128     cpu_put_ccr(env, tstate >> 32);
 129     env->asi = extract64(tstate, 24, 8);
 130 #else
 131     /*
 132      * User can only change condition codes and FPU enabling in %psr.
 133      * But don't bother with FPU enabling, since a real kernel would
 134      * just re-enable the FPU upon the next fpu trap.
 135      */
 136     uint32_t psr;
 137     __get_user(psr, &regs->psr);
 138     env->psr = (psr & PSR_ICC) | (env->psr & ~PSR_ICC);
 139 #endif
 140
 141     /* Note that pc and npc are handled in the caller. */
 142
 143     __get_user(env->y, &regs->y);
 144
 145     for (i = 0; i < 8; i++) {
 146         __get_user(env->gregs[i], &regs->u_regs[i]);
 147     }
 148     for (i = 0; i < 8; i++) {
 149         __get_user(env->regwptr[WREG_O0 + i], &regs->u_regs[i + 8]);
 150     }
 151 }
 152
 153 #define NF_ALIGNEDSZ  (((sizeof(struct target_signal_frame) + 7) & (~7)))
 154
 155 void setup_frame(int sig, struct target_sigaction *ka,
 156                  target_sigset_t *set, CPUSPARCState *env)
 157 {
 158     abi_ulong sf_addr;
 159     struct target_signal_frame *sf;
 160     int sigframe_size, i;
 161
 162     /* 1. Make sure everything is clean */
 163     //synchronize_user_stack();
 164
 165     sigframe_size = NF_ALIGNEDSZ;
 166     sf_addr = get_sigframe(ka, env, sigframe_size);
 167     trace_user_setup_frame(env, sf_addr);
 168
 169     sf = lock_user(VERIFY_WRITE, sf_addr,
 170                    sizeof(struct target_signal_frame), 0);
 171     if (!sf) {
 172         goto sigsegv;
 173     }
 174     /* 2. Save the current process state */
 175     save_pt_regs(&sf->regs, env);
 176     __put_user(0, &sf->extra_size);
 177
 178     //save_fpu_state(regs, &sf->fpu_state);
 179     //__put_user(&sf->fpu_state, &sf->fpu_save);
 180
 181     __put_user(set->sig[0], &sf->si_mask);
 182     for (i = 0; i < TARGET_NSIG_WORDS - 1; i++) {
 183         __put_user(set->sig[i + 1], &sf->extramask[i]);
 184     }
 185
 186     for (i = 0; i < 8; i++) {
 187         __put_user(env->regwptr[i + WREG_L0], &sf->ss.win.locals[i]);
 188     }
 189     for (i = 0; i < 8; i++) {
 190         __put_user(env->regwptr[i + WREG_I0], &sf->ss.win.ins[i]);
 191     }
 192
 193     /* 3. signal handler back-trampoline and parameters */
 194     env->regwptr[WREG_SP] = sf_addr;
 195     env->regwptr[WREG_O0] = sig;
 196     env->regwptr[WREG_O1] = sf_addr +
 197             offsetof(struct target_signal_frame, regs);
 198     env->regwptr[WREG_O2] = sf_addr +
 199             offsetof(struct target_signal_frame, regs);
 200
 201     /* 4. signal handler */
 202     env->pc = ka->_sa_handler;
 203     env->npc = (env->pc + 4);
 204     /* 5. return to kernel instructions */
 205     if (ka->ka_restorer) {
 206         env->regwptr[WREG_O7] = ka->ka_restorer;
 207     } else {
 208         uint32_t val32;
 209
 210         env->regwptr[WREG_O7] = sf_addr +
 211                 offsetof(struct target_signal_frame, insns) - 2 * 4;
 212
 213         /* mov __NR_sigreturn, %g1 */
 214         val32 = 0x821020d8;
 215         __put_user(val32, &sf->insns[0]);
 216
 217         /* t 0x10 */
 218         val32 = 0x91d02010;
 219         __put_user(val32, &sf->insns[1]);
 220     }
 221     unlock_user(sf, sf_addr, sizeof(struct target_signal_frame));
 222     return;
 223 #if 0
 224 sigill_and_return:
 225     force_sig(TARGET_SIGILL);
 226 #endif
 227 sigsegv:
 228     unlock_user(sf, sf_addr, sizeof(struct target_signal_frame));
 229     force_sigsegv(sig);
 230 }
 231
 232 void setup_rt_frame(int sig, struct target_sigaction *ka,
 233                     target_siginfo_t *info,
 234                     target_sigset_t *set, CPUSPARCState *env)
 235 {
 236     qemu_log_mask(LOG_UNIMP, "setup_rt_frame: not implemented\n");
 237 }
 238
 239 long do_sigreturn(CPUSPARCState *env)
 240 {
 241     abi_ulong sf_addr;
 242     struct target_signal_frame *sf;
 243     abi_ulong pc, npc;
 244     target_sigset_t set;
 245     sigset_t host_set;
 246     int i;
 247
 248     sf_addr = env->regwptr[WREG_SP];
 249     trace_user_do_sigreturn(env, sf_addr);
 250     if (!lock_user_struct(VERIFY_READ, sf, sf_addr, 1)) {
 251         goto segv_and_exit;
 252     }
 253
 254     /* 1. Make sure we are not getting garbage from the user */
 255
 256     if (sf_addr & 3)
 257         goto segv_and_exit;
 258
 259     __get_user(pc,  &sf->regs.pc);
 260     __get_user(npc, &sf->regs.npc);
 261
 262     if ((pc | npc) & 3) {
 263         goto segv_and_exit;
 264     }
 265
 266     /* 2. Restore the state */
 267     restore_pt_regs(&sf->regs, env);
 268     env->pc = pc;
 269     env->npc = npc;
 270
 271     /* FIXME: implement FPU save/restore:
 272      * __get_user(fpu_save, &sf->fpu_save);
 273      * if (fpu_save) {
 274      *     if (restore_fpu_state(env, fpu_save)) {
 275      *         goto segv_and_exit;
 276      *     }
 277      * }
 278      */
 279
 280     __get_user(set.sig[0], &sf->si_mask);
 281     for (i = 1; i < TARGET_NSIG_WORDS; i++) {
 282         __get_user(set.sig[i], &sf->extramask[i - 1]);
 283     }
 284
 285     target_to_host_sigset_internal(&host_set, &set);
 286     set_sigmask(&host_set);
 287
 288     unlock_user_struct(sf, sf_addr, 0);
 289     return -TARGET_QEMU_ESIGRETURN;
 290
 291 segv_and_exit:
 292     unlock_user_struct(sf, sf_addr, 0);
 293     force_sig(TARGET_SIGSEGV);
 294     return -TARGET_QEMU_ESIGRETURN;
 295 }
 296
 297 long do_rt_sigreturn(CPUSPARCState *env)
 298 {
 299     trace_user_do_rt_sigreturn(env, 0);
 300     qemu_log_mask(LOG_UNIMP, "do_rt_sigreturn: not implemented\n");
 301     return -TARGET_ENOSYS;
 302 }
 303
 304 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
 305 #define SPARC_MC_TSTATE 0
 306 #define SPARC_MC_PC 1
 307 #define SPARC_MC_NPC 2
 308 #define SPARC_MC_Y 3
 309 #define SPARC_MC_G1 4
 310 #define SPARC_MC_G2 5
 311 #define SPARC_MC_G3 6
 312 #define SPARC_MC_G4 7
 313 #define SPARC_MC_G5 8
 314 #define SPARC_MC_G6 9
 315 #define SPARC_MC_G7 10
 316 #define SPARC_MC_O0 11
 317 #define SPARC_MC_O1 12
 318 #define SPARC_MC_O2 13
 319 #define SPARC_MC_O3 14
 320 #define SPARC_MC_O4 15
 321 #define SPARC_MC_O5 16
 322 #define SPARC_MC_O6 17
 323 #define SPARC_MC_O7 18
 324 #define SPARC_MC_NGREG 19
 325
 326 typedef abi_ulong target_mc_greg_t;
 327 typedef target_mc_greg_t target_mc_gregset_t[SPARC_MC_NGREG];
 328
 329 struct target_mc_fq {
 330     abi_ulong mcfq_addr;
 331     uint32_t mcfq_insn;
 332 };
 333
 334 /*
 335  * Note the manual 16-alignment; the kernel gets this because it
 336  * includes a "long double qregs[16]" in the mcpu_fregs union,
 337  * which we can't do.
 338  */
 339 struct target_mc_fpu {
 340     union {
 341         uint32_t sregs[32];
 342         uint64_t dregs[32];
 343         //uint128_t qregs[16];
 344     } mcfpu_fregs;
 345     abi_ulong mcfpu_fsr;
 346     abi_ulong mcfpu_fprs;
 347     abi_ulong mcfpu_gsr;
 348     abi_ulong mcfpu_fq;
 349     unsigned char mcfpu_qcnt;
 350     unsigned char mcfpu_qentsz;
 351     unsigned char mcfpu_enab;
 352 } __attribute__((aligned(16)));
 353 typedef struct target_mc_fpu target_mc_fpu_t;
 354
 355 typedef struct {
 356     target_mc_gregset_t mc_gregs;
 357     target_mc_greg_t mc_fp;
 358     target_mc_greg_t mc_i7;
 359     target_mc_fpu_t mc_fpregs;
 360 } target_mcontext_t;
 361
 362 struct target_ucontext {
 363     abi_ulong tuc_link;
 364     abi_ulong tuc_flags;
 365     target_sigset_t tuc_sigmask;
 366     target_mcontext_t tuc_mcontext;
 367 };
 368
 369 /* {set, get}context() needed for 64-bit SparcLinux userland. */
 370 void sparc64_set_context(CPUSPARCState *env)
 371 {
 372     abi_ulong ucp_addr;
 373     struct target_ucontext *ucp;
 374     target_mc_gregset_t *grp;
 375     target_mc_fpu_t *fpup;
 376     abi_ulong pc, npc, tstate;
 377     unsigned int i;
 378     unsigned char fenab;
 379
 380     ucp_addr = env->regwptr[WREG_O0];
 381     if (!lock_user_struct(VERIFY_READ, ucp, ucp_addr, 1)) {
 382         goto do_sigsegv;
 383     }
 384     grp  = &ucp->tuc_mcontext.mc_gregs;
 385     __get_user(pc, &((*grp)[SPARC_MC_PC]));
 386     __get_user(npc, &((*grp)[SPARC_MC_NPC]));
 387     if ((pc | npc) & 3) {
 388         goto do_sigsegv;
 389     }
 390     if (env->regwptr[WREG_O1]) {
 391         target_sigset_t target_set;
 392         sigset_t set;
 393
 394         if (TARGET_NSIG_WORDS == 1) {
 395             __get_user(target_set.sig[0], &ucp->tuc_sigmask.sig[0]);
 396         } else {
 397             abi_ulong *src, *dst;
 398             src = ucp->tuc_sigmask.sig;
 399             dst = target_set.sig;
 400             for (i = 0; i < TARGET_NSIG_WORDS; i++, dst++, src++) {
 401                 __get_user(*dst, src);
 402             }
 403         }
 404         target_to_host_sigset_internal(&set, &target_set);
 405         set_sigmask(&set);
 406     }
 407     env->pc = pc;
 408     env->npc = npc;
 409     __get_user(env->y, &((*grp)[SPARC_MC_Y]));
 410     __get_user(tstate, &((*grp)[SPARC_MC_TSTATE]));
 411     /* Honour TSTATE_ASI, TSTATE_ICC and TSTATE_XCC only */
 412     env->asi = (tstate >> 24) & 0xff;
 413     cpu_put_ccr(env, (tstate >> 32) & 0xff);
 414     __get_user(env->gregs[1], (&(*grp)[SPARC_MC_G1]));
 415     __get_user(env->gregs[2], (&(*grp)[SPARC_MC_G2]));
 416     __get_user(env->gregs[3], (&(*grp)[SPARC_MC_G3]));
 417     __get_user(env->gregs[4], (&(*grp)[SPARC_MC_G4]));
 418     __get_user(env->gregs[5], (&(*grp)[SPARC_MC_G5]));
 419     __get_user(env->gregs[6], (&(*grp)[SPARC_MC_G6]));
 420     /* Skip g7 as that's the thread register in userspace */
 421
 422     /*
 423      * Note that unlike the kernel, we didn't need to mess with the
 424      * guest register window state to save it into a pt_regs to run
 425      * the kernel. So for us the guest's O regs are still in WREG_O*
 426      * (unlike the kernel which has put them in UREG_I* in a pt_regs)
 427      * and the fp and i7 are still in WREG_I6 and WREG_I7 and don't
 428      * need to be written back to userspace memory.
 429      */
 430     __get_user(env->regwptr[WREG_O0], (&(*grp)[SPARC_MC_O0]));
 431     __get_user(env->regwptr[WREG_O1], (&(*grp)[SPARC_MC_O1]));
 432     __get_user(env->regwptr[WREG_O2], (&(*grp)[SPARC_MC_O2]));
 433     __get_user(env->regwptr[WREG_O3], (&(*grp)[SPARC_MC_O3]));
 434     __get_user(env->regwptr[WREG_O4], (&(*grp)[SPARC_MC_O4]));
 435     __get_user(env->regwptr[WREG_O5], (&(*grp)[SPARC_MC_O5]));
 436     __get_user(env->regwptr[WREG_O6], (&(*grp)[SPARC_MC_O6]));
 437     __get_user(env->regwptr[WREG_O7], (&(*grp)[SPARC_MC_O7]));
 438
 439     __get_user(env->regwptr[WREG_FP], &(ucp->tuc_mcontext.mc_fp));
 440     __get_user(env->regwptr[WREG_I7], &(ucp->tuc_mcontext.mc_i7));
 441
 442     fpup = &ucp->tuc_mcontext.mc_fpregs;
 443
 444     __get_user(fenab, &(fpup->mcfpu_enab));
 445     if (fenab) {
 446         abi_ulong fprs;
 447
 448         /*
 449          * We use the FPRS from the guest only in deciding whether
 450          * to restore the upper, lower, or both banks of the FPU regs.
 451          * The kernel here writes the FPU register data into the
 452          * process's current_thread_info state and unconditionally
 453          * clears FPRS and TSTATE_PEF: this disables the FPU so that the
 454          * next FPU-disabled trap will copy the data out of
 455          * current_thread_info and into the real FPU registers.
 456          * QEMU doesn't need to handle lazy-FPU-state-restoring like that,
 457          * so we always load the data directly into the FPU registers
 458          * and leave FPRS and TSTATE_PEF alone (so the FPU stays enabled).
 459          * Note that because we (and the kernel) always write zeroes for
 460          * the fenab and fprs in sparc64_get_context() none of this code
 461          * will execute unless the guest manually constructed or changed
 462          * the context structure.
 463          */
 464         __get_user(fprs, &(fpup->mcfpu_fprs));
 465         if (fprs & FPRS_DL) {
 466             for (i = 0; i < 16; i++) {
 467                 __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i]));
 468             }
 469         }
 470         if (fprs & FPRS_DU) {
 471             for (i = 16; i < 32; i++) {
 472                 __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i]));
 473             }
 474         }
 475         __get_user(env->fsr, &(fpup->mcfpu_fsr));
 476         __get_user(env->gsr, &(fpup->mcfpu_gsr));
 477     }
 478     unlock_user_struct(ucp, ucp_addr, 0);
 479     return;
 480 do_sigsegv:
 481     unlock_user_struct(ucp, ucp_addr, 0);
 482     force_sig(TARGET_SIGSEGV);
 483 }
 484
 485 void sparc64_get_context(CPUSPARCState *env)
 486 {
 487     abi_ulong ucp_addr;
 488     struct target_ucontext *ucp;
 489     target_mc_gregset_t *grp;
 490     target_mcontext_t *mcp;
 491     int err;
 492     unsigned int i;
 493     target_sigset_t target_set;
 494     sigset_t set;
 495
 496     ucp_addr = env->regwptr[WREG_O0];
 497     if (!lock_user_struct(VERIFY_WRITE, ucp, ucp_addr, 0)) {
 498         goto do_sigsegv;
 499     }
 500
 501     memset(ucp, 0, sizeof(*ucp));
 502
 503     mcp = &ucp->tuc_mcontext;
 504     grp = &mcp->mc_gregs;
 505
 506     /* Skip over the trap instruction, first. */
 507     env->pc = env->npc;
 508     env->npc += 4;
 509
 510     /* If we're only reading the signal mask then do_sigprocmask()
 511      * is guaranteed not to fail, which is important because we don't
 512      * have any way to signal a failure or restart this operation since
 513      * this is not a normal syscall.
 514      */
 515     err = do_sigprocmask(0, NULL, &set);
 516     assert(err == 0);
 517     host_to_target_sigset_internal(&target_set, &set);
 518     if (TARGET_NSIG_WORDS == 1) {
 519         __put_user(target_set.sig[0],
 520                    (abi_ulong *)&ucp->tuc_sigmask);
 521     } else {
 522         abi_ulong *src, *dst;
 523         src = target_set.sig;
 524         dst = ucp->tuc_sigmask.sig;
 525         for (i = 0; i < TARGET_NSIG_WORDS; i++, dst++, src++) {
 526             __put_user(*src, dst);
 527         }
 528     }
 529
 530     __put_user(sparc64_tstate(env), &((*grp)[SPARC_MC_TSTATE]));
 531     __put_user(env->pc, &((*grp)[SPARC_MC_PC]));
 532     __put_user(env->npc, &((*grp)[SPARC_MC_NPC]));
 533     __put_user(env->y, &((*grp)[SPARC_MC_Y]));
 534     __put_user(env->gregs[1], &((*grp)[SPARC_MC_G1]));
 535     __put_user(env->gregs[2], &((*grp)[SPARC_MC_G2]));
 536     __put_user(env->gregs[3], &((*grp)[SPARC_MC_G3]));
 537     __put_user(env->gregs[4], &((*grp)[SPARC_MC_G4]));
 538     __put_user(env->gregs[5], &((*grp)[SPARC_MC_G5]));
 539     __put_user(env->gregs[6], &((*grp)[SPARC_MC_G6]));
 540     __put_user(env->gregs[7], &((*grp)[SPARC_MC_G7]));
 541
 542     /*
 543      * Note that unlike the kernel, we didn't need to mess with the
 544      * guest register window state to save it into a pt_regs to run
 545      * the kernel. So for us the guest's O regs are still in WREG_O*
 546      * (unlike the kernel which has put them in UREG_I* in a pt_regs)
 547      * and the fp and i7 are still in WREG_I6 and WREG_I7 and don't
 548      * need to be fished out of userspace memory.
 549      */
 550     __put_user(env->regwptr[WREG_O0], &((*grp)[SPARC_MC_O0]));
 551     __put_user(env->regwptr[WREG_O1], &((*grp)[SPARC_MC_O1]));
 552     __put_user(env->regwptr[WREG_O2], &((*grp)[SPARC_MC_O2]));
 553     __put_user(env->regwptr[WREG_O3], &((*grp)[SPARC_MC_O3]));
 554     __put_user(env->regwptr[WREG_O4], &((*grp)[SPARC_MC_O4]));
 555     __put_user(env->regwptr[WREG_O5], &((*grp)[SPARC_MC_O5]));
 556     __put_user(env->regwptr[WREG_O6], &((*grp)[SPARC_MC_O6]));
 557     __put_user(env->regwptr[WREG_O7], &((*grp)[SPARC_MC_O7]));
 558
 559     __put_user(env->regwptr[WREG_FP], &(mcp->mc_fp));
 560     __put_user(env->regwptr[WREG_I7], &(mcp->mc_i7));
 561
 562     /*
 563      * We don't write out the FPU state. This matches the kernel's
 564      * implementation (which has the code for doing this but
 565      * hidden behind an "if (fenab)" where fenab is always 0).
 566      */
 567
 568     unlock_user_struct(ucp, ucp_addr, 1);
 569     return;
 570 do_sigsegv:
 571     unlock_user_struct(ucp, ucp_addr, 1);
 572     force_sig(TARGET_SIGSEGV);
 573 }
 574 #endif