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 stack frame */
  25 struct sparc_stackf {
  26     abi_ulong locals[8];
  27     abi_ulong ins[8];
  28     /* It's simpler to treat fp and callers_pc as elements of ins[]
  29          * since we never need to access them ourselves.
  30          */
  31     char *structptr;
  32     abi_ulong xargs[6];
  33     abi_ulong xxargs[1];
  34 };
  35
  36 typedef struct {
  37     struct {
  38         abi_ulong psr;
  39         abi_ulong pc;
  40         abi_ulong npc;
  41         abi_ulong y;
  42         abi_ulong u_regs[16]; /* globals and ins */
  43     }               si_regs;
  44     int             si_mask;
  45 } __siginfo_t;
  46
  47 typedef struct {
  48     abi_ulong  si_float_regs[32];
  49     unsigned   long si_fsr;
  50     unsigned   long si_fpqdepth;
  51     struct {
  52         unsigned long *insn_addr;
  53         unsigned long insn;
  54     } si_fpqueue [16];
  55 } qemu_siginfo_fpu_t;
  56
  57
  58 struct target_signal_frame {
  59     struct sparc_stackf ss;
  60     __siginfo_t         info;
  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 int
  97 setup___siginfo(__siginfo_t *si, CPUSPARCState *env, abi_ulong mask)
  98 {
  99     int err = 0, i;
 100
 101     __put_user(env->psr, &si->si_regs.psr);
 102     __put_user(env->pc, &si->si_regs.pc);
 103     __put_user(env->npc, &si->si_regs.npc);
 104     __put_user(env->y, &si->si_regs.y);
 105     for (i=0; i < 8; i++) {
 106         __put_user(env->gregs[i], &si->si_regs.u_regs[i]);
 107     }
 108     for (i=0; i < 8; i++) {
 109         __put_user(env->regwptr[WREG_O0 + i], &si->si_regs.u_regs[i + 8]);
 110     }
 111     __put_user(mask, &si->si_mask);
 112     return err;
 113 }
 114
 115 #define NF_ALIGNEDSZ  (((sizeof(struct target_signal_frame) + 7) & (~7)))
 116
 117 void setup_frame(int sig, struct target_sigaction *ka,
 118                  target_sigset_t *set, CPUSPARCState *env)
 119 {
 120     abi_ulong sf_addr;
 121     struct target_signal_frame *sf;
 122     int sigframe_size, err, i;
 123
 124     /* 1. Make sure everything is clean */
 125     //synchronize_user_stack();
 126
 127     sigframe_size = NF_ALIGNEDSZ;
 128     sf_addr = get_sigframe(ka, env, sigframe_size);
 129     trace_user_setup_frame(env, sf_addr);
 130
 131     sf = lock_user(VERIFY_WRITE, sf_addr,
 132                    sizeof(struct target_signal_frame), 0);
 133     if (!sf) {
 134         goto sigsegv;
 135     }
 136 #if 0
 137     if (invalid_frame_pointer(sf, sigframe_size))
 138         goto sigill_and_return;
 139 #endif
 140     /* 2. Save the current process state */
 141     err = setup___siginfo(&sf->info, env, set->sig[0]);
 142     __put_user(0, &sf->extra_size);
 143
 144     //save_fpu_state(regs, &sf->fpu_state);
 145     //__put_user(&sf->fpu_state, &sf->fpu_save);
 146
 147     __put_user(set->sig[0], &sf->info.si_mask);
 148     for (i = 0; i < TARGET_NSIG_WORDS - 1; i++) {
 149         __put_user(set->sig[i + 1], &sf->extramask[i]);
 150     }
 151
 152     for (i = 0; i < 8; i++) {
 153         __put_user(env->regwptr[i + WREG_L0], &sf->ss.locals[i]);
 154     }
 155     for (i = 0; i < 8; i++) {
 156         __put_user(env->regwptr[i + WREG_I0], &sf->ss.ins[i]);
 157     }
 158     if (err)
 159         goto sigsegv;
 160
 161     /* 3. signal handler back-trampoline and parameters */
 162     env->regwptr[WREG_SP] = sf_addr;
 163     env->regwptr[WREG_O0] = sig;
 164     env->regwptr[WREG_O1] = sf_addr +
 165             offsetof(struct target_signal_frame, info);
 166     env->regwptr[WREG_O2] = sf_addr +
 167             offsetof(struct target_signal_frame, info);
 168
 169     /* 4. signal handler */
 170     env->pc = ka->_sa_handler;
 171     env->npc = (env->pc + 4);
 172     /* 5. return to kernel instructions */
 173     if (ka->ka_restorer) {
 174         env->regwptr[WREG_O7] = ka->ka_restorer;
 175     } else {
 176         uint32_t val32;
 177
 178         env->regwptr[WREG_O7] = sf_addr +
 179                 offsetof(struct target_signal_frame, insns) - 2 * 4;
 180
 181         /* mov __NR_sigreturn, %g1 */
 182         val32 = 0x821020d8;
 183         __put_user(val32, &sf->insns[0]);
 184
 185         /* t 0x10 */
 186         val32 = 0x91d02010;
 187         __put_user(val32, &sf->insns[1]);
 188     }
 189     unlock_user(sf, sf_addr, sizeof(struct target_signal_frame));
 190     return;
 191 #if 0
 192 sigill_and_return:
 193     force_sig(TARGET_SIGILL);
 194 #endif
 195 sigsegv:
 196     unlock_user(sf, sf_addr, sizeof(struct target_signal_frame));
 197     force_sigsegv(sig);
 198 }
 199
 200 void setup_rt_frame(int sig, struct target_sigaction *ka,
 201                     target_siginfo_t *info,
 202                     target_sigset_t *set, CPUSPARCState *env)
 203 {
 204     qemu_log_mask(LOG_UNIMP, "setup_rt_frame: not implemented\n");
 205 }
 206
 207 long do_sigreturn(CPUSPARCState *env)
 208 {
 209     abi_ulong sf_addr;
 210     struct target_signal_frame *sf;
 211     abi_ulong up_psr, pc, npc;
 212     target_sigset_t set;
 213     sigset_t host_set;
 214     int i;
 215
 216     sf_addr = env->regwptr[WREG_SP];
 217     trace_user_do_sigreturn(env, sf_addr);
 218     if (!lock_user_struct(VERIFY_READ, sf, sf_addr, 1)) {
 219         goto segv_and_exit;
 220     }
 221
 222     /* 1. Make sure we are not getting garbage from the user */
 223
 224     if (sf_addr & 3)
 225         goto segv_and_exit;
 226
 227     __get_user(pc,  &sf->info.si_regs.pc);
 228     __get_user(npc, &sf->info.si_regs.npc);
 229
 230     if ((pc | npc) & 3) {
 231         goto segv_and_exit;
 232     }
 233
 234     /* 2. Restore the state */
 235     __get_user(up_psr, &sf->info.si_regs.psr);
 236
 237     /* User can only change condition codes and FPU enabling in %psr. */
 238     env->psr = (up_psr & (PSR_ICC /* | PSR_EF */))
 239             | (env->psr & ~(PSR_ICC /* | PSR_EF */));
 240
 241     env->pc = pc;
 242     env->npc = npc;
 243     __get_user(env->y, &sf->info.si_regs.y);
 244     for (i=0; i < 8; i++) {
 245         __get_user(env->gregs[i], &sf->info.si_regs.u_regs[i]);
 246     }
 247     for (i=0; i < 8; i++) {
 248         __get_user(env->regwptr[i + WREG_O0], &sf->info.si_regs.u_regs[i + 8]);
 249     }
 250
 251     /* FIXME: implement FPU save/restore:
 252      * __get_user(fpu_save, &sf->fpu_save);
 253      * if (fpu_save) {
 254      *     if (restore_fpu_state(env, fpu_save)) {
 255      *         goto segv_and_exit;
 256      *     }
 257      * }
 258      */
 259
 260     /* This is pretty much atomic, no amount locking would prevent
 261          * the races which exist anyways.
 262          */
 263     __get_user(set.sig[0], &sf->info.si_mask);
 264     for(i = 1; i < TARGET_NSIG_WORDS; i++) {
 265         __get_user(set.sig[i], &sf->extramask[i - 1]);
 266     }
 267
 268     target_to_host_sigset_internal(&host_set, &set);
 269     set_sigmask(&host_set);
 270
 271     unlock_user_struct(sf, sf_addr, 0);
 272     return -TARGET_QEMU_ESIGRETURN;
 273
 274 segv_and_exit:
 275     unlock_user_struct(sf, sf_addr, 0);
 276     force_sig(TARGET_SIGSEGV);
 277     return -TARGET_QEMU_ESIGRETURN;
 278 }
 279
 280 long do_rt_sigreturn(CPUSPARCState *env)
 281 {
 282     trace_user_do_rt_sigreturn(env, 0);
 283     qemu_log_mask(LOG_UNIMP, "do_rt_sigreturn: not implemented\n");
 284     return -TARGET_ENOSYS;
 285 }
 286
 287 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
 288 #define SPARC_MC_TSTATE 0
 289 #define SPARC_MC_PC 1
 290 #define SPARC_MC_NPC 2
 291 #define SPARC_MC_Y 3
 292 #define SPARC_MC_G1 4
 293 #define SPARC_MC_G2 5
 294 #define SPARC_MC_G3 6
 295 #define SPARC_MC_G4 7
 296 #define SPARC_MC_G5 8
 297 #define SPARC_MC_G6 9
 298 #define SPARC_MC_G7 10
 299 #define SPARC_MC_O0 11
 300 #define SPARC_MC_O1 12
 301 #define SPARC_MC_O2 13
 302 #define SPARC_MC_O3 14
 303 #define SPARC_MC_O4 15
 304 #define SPARC_MC_O5 16
 305 #define SPARC_MC_O6 17
 306 #define SPARC_MC_O7 18
 307 #define SPARC_MC_NGREG 19
 308
 309 typedef abi_ulong target_mc_greg_t;
 310 typedef target_mc_greg_t target_mc_gregset_t[SPARC_MC_NGREG];
 311
 312 struct target_mc_fq {
 313     abi_ulong mcfq_addr;
 314     uint32_t mcfq_insn;
 315 };
 316
 317 /*
 318  * Note the manual 16-alignment; the kernel gets this because it
 319  * includes a "long double qregs[16]" in the mcpu_fregs union,
 320  * which we can't do.
 321  */
 322 struct target_mc_fpu {
 323     union {
 324         uint32_t sregs[32];
 325         uint64_t dregs[32];
 326         //uint128_t qregs[16];
 327     } mcfpu_fregs;
 328     abi_ulong mcfpu_fsr;
 329     abi_ulong mcfpu_fprs;
 330     abi_ulong mcfpu_gsr;
 331     abi_ulong mcfpu_fq;
 332     unsigned char mcfpu_qcnt;
 333     unsigned char mcfpu_qentsz;
 334     unsigned char mcfpu_enab;
 335 } __attribute__((aligned(16)));
 336 typedef struct target_mc_fpu target_mc_fpu_t;
 337
 338 typedef struct {
 339     target_mc_gregset_t mc_gregs;
 340     target_mc_greg_t mc_fp;
 341     target_mc_greg_t mc_i7;
 342     target_mc_fpu_t mc_fpregs;
 343 } target_mcontext_t;
 344
 345 struct target_ucontext {
 346     abi_ulong tuc_link;
 347     abi_ulong tuc_flags;
 348     target_sigset_t tuc_sigmask;
 349     target_mcontext_t tuc_mcontext;
 350 };
 351
 352 /* A V9 register window */
 353 struct target_reg_window {
 354     abi_ulong locals[8];
 355     abi_ulong ins[8];
 356 };
 357
 358 /* {set, get}context() needed for 64-bit SparcLinux userland. */
 359 void sparc64_set_context(CPUSPARCState *env)
 360 {
 361     abi_ulong ucp_addr;
 362     struct target_ucontext *ucp;
 363     target_mc_gregset_t *grp;
 364     target_mc_fpu_t *fpup;
 365     abi_ulong pc, npc, tstate;
 366     unsigned int i;
 367     unsigned char fenab;
 368
 369     ucp_addr = env->regwptr[WREG_O0];
 370     if (!lock_user_struct(VERIFY_READ, ucp, ucp_addr, 1)) {
 371         goto do_sigsegv;
 372     }
 373     grp  = &ucp->tuc_mcontext.mc_gregs;
 374     __get_user(pc, &((*grp)[SPARC_MC_PC]));
 375     __get_user(npc, &((*grp)[SPARC_MC_NPC]));
 376     if ((pc | npc) & 3) {
 377         goto do_sigsegv;
 378     }
 379     if (env->regwptr[WREG_O1]) {
 380         target_sigset_t target_set;
 381         sigset_t set;
 382
 383         if (TARGET_NSIG_WORDS == 1) {
 384             __get_user(target_set.sig[0], &ucp->tuc_sigmask.sig[0]);
 385         } else {
 386             abi_ulong *src, *dst;
 387             src = ucp->tuc_sigmask.sig;
 388             dst = target_set.sig;
 389             for (i = 0; i < TARGET_NSIG_WORDS; i++, dst++, src++) {
 390                 __get_user(*dst, src);
 391             }
 392         }
 393         target_to_host_sigset_internal(&set, &target_set);
 394         set_sigmask(&set);
 395     }
 396     env->pc = pc;
 397     env->npc = npc;
 398     __get_user(env->y, &((*grp)[SPARC_MC_Y]));
 399     __get_user(tstate, &((*grp)[SPARC_MC_TSTATE]));
 400     /* Honour TSTATE_ASI, TSTATE_ICC and TSTATE_XCC only */
 401     env->asi = (tstate >> 24) & 0xff;
 402     cpu_put_ccr(env, (tstate >> 32) & 0xff);
 403     __get_user(env->gregs[1], (&(*grp)[SPARC_MC_G1]));
 404     __get_user(env->gregs[2], (&(*grp)[SPARC_MC_G2]));
 405     __get_user(env->gregs[3], (&(*grp)[SPARC_MC_G3]));
 406     __get_user(env->gregs[4], (&(*grp)[SPARC_MC_G4]));
 407     __get_user(env->gregs[5], (&(*grp)[SPARC_MC_G5]));
 408     __get_user(env->gregs[6], (&(*grp)[SPARC_MC_G6]));
 409     /* Skip g7 as that's the thread register in userspace */
 410
 411     /*
 412      * Note that unlike the kernel, we didn't need to mess with the
 413      * guest register window state to save it into a pt_regs to run
 414      * the kernel. So for us the guest's O regs are still in WREG_O*
 415      * (unlike the kernel which has put them in UREG_I* in a pt_regs)
 416      * and the fp and i7 are still in WREG_I6 and WREG_I7 and don't
 417      * need to be written back to userspace memory.
 418      */
 419     __get_user(env->regwptr[WREG_O0], (&(*grp)[SPARC_MC_O0]));
 420     __get_user(env->regwptr[WREG_O1], (&(*grp)[SPARC_MC_O1]));
 421     __get_user(env->regwptr[WREG_O2], (&(*grp)[SPARC_MC_O2]));
 422     __get_user(env->regwptr[WREG_O3], (&(*grp)[SPARC_MC_O3]));
 423     __get_user(env->regwptr[WREG_O4], (&(*grp)[SPARC_MC_O4]));
 424     __get_user(env->regwptr[WREG_O5], (&(*grp)[SPARC_MC_O5]));
 425     __get_user(env->regwptr[WREG_O6], (&(*grp)[SPARC_MC_O6]));
 426     __get_user(env->regwptr[WREG_O7], (&(*grp)[SPARC_MC_O7]));
 427
 428     __get_user(env->regwptr[WREG_FP], &(ucp->tuc_mcontext.mc_fp));
 429     __get_user(env->regwptr[WREG_I7], &(ucp->tuc_mcontext.mc_i7));
 430
 431     fpup = &ucp->tuc_mcontext.mc_fpregs;
 432
 433     __get_user(fenab, &(fpup->mcfpu_enab));
 434     if (fenab) {
 435         abi_ulong fprs;
 436
 437         /*
 438          * We use the FPRS from the guest only in deciding whether
 439          * to restore the upper, lower, or both banks of the FPU regs.
 440          * The kernel here writes the FPU register data into the
 441          * process's current_thread_info state and unconditionally
 442          * clears FPRS and TSTATE_PEF: this disables the FPU so that the
 443          * next FPU-disabled trap will copy the data out of
 444          * current_thread_info and into the real FPU registers.
 445          * QEMU doesn't need to handle lazy-FPU-state-restoring like that,
 446          * so we always load the data directly into the FPU registers
 447          * and leave FPRS and TSTATE_PEF alone (so the FPU stays enabled).
 448          * Note that because we (and the kernel) always write zeroes for
 449          * the fenab and fprs in sparc64_get_context() none of this code
 450          * will execute unless the guest manually constructed or changed
 451          * the context structure.
 452          */
 453         __get_user(fprs, &(fpup->mcfpu_fprs));
 454         if (fprs & FPRS_DL) {
 455             for (i = 0; i < 16; i++) {
 456                 __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i]));
 457             }
 458         }
 459         if (fprs & FPRS_DU) {
 460             for (i = 16; i < 32; i++) {
 461                 __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i]));
 462             }
 463         }
 464         __get_user(env->fsr, &(fpup->mcfpu_fsr));
 465         __get_user(env->gsr, &(fpup->mcfpu_gsr));
 466     }
 467     unlock_user_struct(ucp, ucp_addr, 0);
 468     return;
 469 do_sigsegv:
 470     unlock_user_struct(ucp, ucp_addr, 0);
 471     force_sig(TARGET_SIGSEGV);
 472 }
 473
 474 void sparc64_get_context(CPUSPARCState *env)
 475 {
 476     abi_ulong ucp_addr;
 477     struct target_ucontext *ucp;
 478     target_mc_gregset_t *grp;
 479     target_mcontext_t *mcp;
 480     int err;
 481     unsigned int i;
 482     target_sigset_t target_set;
 483     sigset_t set;
 484
 485     ucp_addr = env->regwptr[WREG_O0];
 486     if (!lock_user_struct(VERIFY_WRITE, ucp, ucp_addr, 0)) {
 487         goto do_sigsegv;
 488     }
 489
 490     memset(ucp, 0, sizeof(*ucp));
 491
 492     mcp = &ucp->tuc_mcontext;
 493     grp = &mcp->mc_gregs;
 494
 495     /* Skip over the trap instruction, first. */
 496     env->pc = env->npc;
 497     env->npc += 4;
 498
 499     /* If we're only reading the signal mask then do_sigprocmask()
 500      * is guaranteed not to fail, which is important because we don't
 501      * have any way to signal a failure or restart this operation since
 502      * this is not a normal syscall.
 503      */
 504     err = do_sigprocmask(0, NULL, &set);
 505     assert(err == 0);
 506     host_to_target_sigset_internal(&target_set, &set);
 507     if (TARGET_NSIG_WORDS == 1) {
 508         __put_user(target_set.sig[0],
 509                    (abi_ulong *)&ucp->tuc_sigmask);
 510     } else {
 511         abi_ulong *src, *dst;
 512         src = target_set.sig;
 513         dst = ucp->tuc_sigmask.sig;
 514         for (i = 0; i < TARGET_NSIG_WORDS; i++, dst++, src++) {
 515             __put_user(*src, dst);
 516         }
 517     }
 518
 519     __put_user(sparc64_tstate(env), &((*grp)[SPARC_MC_TSTATE]));
 520     __put_user(env->pc, &((*grp)[SPARC_MC_PC]));
 521     __put_user(env->npc, &((*grp)[SPARC_MC_NPC]));
 522     __put_user(env->y, &((*grp)[SPARC_MC_Y]));
 523     __put_user(env->gregs[1], &((*grp)[SPARC_MC_G1]));
 524     __put_user(env->gregs[2], &((*grp)[SPARC_MC_G2]));
 525     __put_user(env->gregs[3], &((*grp)[SPARC_MC_G3]));
 526     __put_user(env->gregs[4], &((*grp)[SPARC_MC_G4]));
 527     __put_user(env->gregs[5], &((*grp)[SPARC_MC_G5]));
 528     __put_user(env->gregs[6], &((*grp)[SPARC_MC_G6]));
 529     __put_user(env->gregs[7], &((*grp)[SPARC_MC_G7]));
 530
 531     /*
 532      * Note that unlike the kernel, we didn't need to mess with the
 533      * guest register window state to save it into a pt_regs to run
 534      * the kernel. So for us the guest's O regs are still in WREG_O*
 535      * (unlike the kernel which has put them in UREG_I* in a pt_regs)
 536      * and the fp and i7 are still in WREG_I6 and WREG_I7 and don't
 537      * need to be fished out of userspace memory.
 538      */
 539     __put_user(env->regwptr[WREG_O0], &((*grp)[SPARC_MC_O0]));
 540     __put_user(env->regwptr[WREG_O1], &((*grp)[SPARC_MC_O1]));
 541     __put_user(env->regwptr[WREG_O2], &((*grp)[SPARC_MC_O2]));
 542     __put_user(env->regwptr[WREG_O3], &((*grp)[SPARC_MC_O3]));
 543     __put_user(env->regwptr[WREG_O4], &((*grp)[SPARC_MC_O4]));
 544     __put_user(env->regwptr[WREG_O5], &((*grp)[SPARC_MC_O5]));
 545     __put_user(env->regwptr[WREG_O6], &((*grp)[SPARC_MC_O6]));
 546     __put_user(env->regwptr[WREG_O7], &((*grp)[SPARC_MC_O7]));
 547
 548     __put_user(env->regwptr[WREG_FP], &(mcp->mc_fp));
 549     __put_user(env->regwptr[WREG_I7], &(mcp->mc_i7));
 550
 551     /*
 552      * We don't write out the FPU state. This matches the kernel's
 553      * implementation (which has the code for doing this but
 554      * hidden behind an "if (fenab)" where fenab is always 0).
 555      */
 556
 557     unlock_user_struct(ucp, ucp_addr, 1);
 558     return;
 559 do_sigsegv:
 560     unlock_user_struct(ucp, ucp_addr, 1);
 561     force_sig(TARGET_SIGSEGV);
 562 }
 563 #endif