arch/sparc64/kernel/process.c

   1 /*  $Id: process.c,v 1.131 2002/02/09 19:49:30 davem Exp $
   2  *  arch/sparc64/kernel/process.c
   3  *
   4  *  Copyright (C) 1995, 1996 David S. Miller (davem@caip.rutgers.edu)
   5  *  Copyright (C) 1996       Eddie C. Dost   (ecd@skynet.be)
   6  *  Copyright (C) 1997, 1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
   7  */
   8
   9 /*
  10  * This file handles the architecture-dependent parts of process handling..
  11  */
  12
  13 #include <stdarg.h>
  14
  15 #include <linux/errno.h>
  16 #include <linux/module.h>
  17 #include <linux/sched.h>
  18 #include <linux/kernel.h>
  19 #include <linux/kallsyms.h>
  20 #include <linux/mm.h>
  21 #include <linux/fs.h>
  22 #include <linux/smp.h>
  23 #include <linux/stddef.h>
  24 #include <linux/ptrace.h>
  25 #include <linux/slab.h>
  26 #include <linux/user.h>
  27 #include <linux/reboot.h>
  28 #include <linux/delay.h>
  29 #include <linux/compat.h>
  30 #include <linux/tick.h>
  31 #include <linux/init.h>
  32 #include <linux/cpu.h>
  33 #include <linux/elfcore.h>
  34
  35 #include <asm/oplib.h>
  36 #include <asm/uaccess.h>
  37 #include <asm/system.h>
  38 #include <asm/page.h>
  39 #include <asm/pgalloc.h>
  40 #include <asm/pgtable.h>
  41 #include <asm/processor.h>
  42 #include <asm/pstate.h>
  43 #include <asm/elf.h>
  44 #include <asm/fpumacro.h>
  45 #include <asm/head.h>
  46 #include <asm/cpudata.h>
  47 #include <asm/mmu_context.h>
  48 #include <asm/unistd.h>
  49 #include <asm/hypervisor.h>
  50 #include <asm/sstate.h>
  51 #include <asm/reboot.h>
  52 #include <asm/syscalls.h>
  53
  54 /* #define VERBOSE_SHOWREGS */
  55
  56 static void sparc64_yield(int cpu)
  57 {
  58         if (tlb_type != hypervisor)
  59                 return;
  60
  61         clear_thread_flag(TIF_POLLING_NRFLAG);
  62         smp_mb__after_clear_bit();
  63
  64         while (!need_resched() && !cpu_is_offline(cpu)) {
  65                 unsigned long pstate;
  66
  67                 /* Disable interrupts. */
  68                 __asm__ __volatile__(
  69                         "rdpr %%pstate, %0\n\t"
  70                         "andn %0, %1, %0\n\t"
  71                         "wrpr %0, %%g0, %%pstate"
  72                         : "=&r" (pstate)
  73                         : "i" (PSTATE_IE));
  74
  75                 if (!need_resched() && !cpu_is_offline(cpu))
  76                         sun4v_cpu_yield();
  77
  78                 /* Re-enable interrupts. */
  79                 __asm__ __volatile__(
  80                         "rdpr %%pstate, %0\n\t"
  81                         "or %0, %1, %0\n\t"
  82                         "wrpr %0, %%g0, %%pstate"
  83                         : "=&r" (pstate)
  84                         : "i" (PSTATE_IE));
  85         }
  86
  87         set_thread_flag(TIF_POLLING_NRFLAG);
  88 }
  89
  90 /* The idle loop on sparc64. */
  91 void cpu_idle(void)
  92 {
  93         int cpu = smp_processor_id();
  94
  95         set_thread_flag(TIF_POLLING_NRFLAG);
  96
  97         while(1) {
  98                 tick_nohz_stop_sched_tick();
  99
 100                 while (!need_resched() && !cpu_is_offline(cpu))
 101                         sparc64_yield(cpu);
 102
 103                 tick_nohz_restart_sched_tick();
 104
 105                 preempt_enable_no_resched();
 106
 107 #ifdef CONFIG_HOTPLUG_CPU
 108                 if (cpu_is_offline(cpu))
 109                         cpu_play_dead();
 110 #endif
 111
 112                 schedule();
 113                 preempt_disable();
 114         }
 115 }
 116
 117 extern char reboot_command [];
 118
 119 void machine_halt(void)
 120 {
 121         sstate_halt();
 122         prom_halt();
 123         panic("Halt failed!");
 124 }
 125
 126 void machine_alt_power_off(void)
 127 {
 128         sstate_poweroff();
 129         prom_halt_power_off();
 130         panic("Power-off failed!");
 131 }
 132
 133 void machine_restart(char * cmd)
 134 {
 135         char *p;
 136
 137         sstate_reboot();
 138         p = strchr (reboot_command, '\n');
 139         if (p) *p = 0;
 140         if (cmd)
 141                 prom_reboot(cmd);
 142         if (*reboot_command)
 143                 prom_reboot(reboot_command);
 144         prom_reboot("");
 145         panic("Reboot failed!");
 146 }
 147
 148 #ifdef CONFIG_COMPAT
 149 static void show_regwindow32(struct pt_regs *regs)
 150 {
 151         struct reg_window32 __user *rw;
 152         struct reg_window32 r_w;
 153         mm_segment_t old_fs;
 154
 155         __asm__ __volatile__ ("flushw");
 156         rw = compat_ptr((unsigned)regs->u_regs[14]);
 157         old_fs = get_fs();
 158         set_fs (USER_DS);
 159         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 160                 set_fs (old_fs);
 161                 return;
 162         }
 163
 164         set_fs (old_fs);
 165         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
 166                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
 167                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
 168                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
 169         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
 170                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
 171                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
 172                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
 173 }
 174 #else
 175 #define show_regwindow32(regs)  do { } while (0)
 176 #endif
 177
 178 static void show_regwindow(struct pt_regs *regs)
 179 {
 180         struct reg_window __user *rw;
 181         struct reg_window *rwk;
 182         struct reg_window r_w;
 183         mm_segment_t old_fs;
 184
 185         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 186                 __asm__ __volatile__ ("flushw");
 187                 rw = (struct reg_window __user *)
 188                         (regs->u_regs[14] + STACK_BIAS);
 189                 rwk = (struct reg_window *)
 190                         (regs->u_regs[14] + STACK_BIAS);
 191                 if (!(regs->tstate & TSTATE_PRIV)) {
 192                         old_fs = get_fs();
 193                         set_fs (USER_DS);
 194                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 195                                 set_fs (old_fs);
 196                                 return;
 197                         }
 198                         rwk = &r_w;
 199                         set_fs (old_fs);
 200                 }
 201         } else {
 202                 show_regwindow32(regs);
 203                 return;
 204         }
 205         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 206                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 207         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 208                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 209         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 210                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 211         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 212                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 213         if (regs->tstate & TSTATE_PRIV)
 214                 print_symbol("I7: <%s>\n", rwk->ins[7]);
 215 }
 216
 217 #ifdef CONFIG_SMP
 218 static DEFINE_SPINLOCK(regdump_lock);
 219 #endif
 220
 221 void __show_regs(struct pt_regs * regs)
 222 {
 223 #ifdef CONFIG_SMP
 224         unsigned long flags;
 225
 226         /* Protect against xcall ipis which might lead to livelock on the lock */
 227         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 228                              "wrpr      %0, %1, %%pstate"
 229                              : "=r" (flags)
 230                              : "i" (PSTATE_IE));
 231         spin_lock(&regdump_lock);
 232 #endif
 233         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 234                regs->tpc, regs->tnpc, regs->y, print_tainted());
 235         print_symbol("TPC: <%s>\n", regs->tpc);
 236         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 237                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 238                regs->u_regs[3]);
 239         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 240                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 241                regs->u_regs[7]);
 242         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 243                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 244                regs->u_regs[11]);
 245         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 246                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 247                regs->u_regs[15]);
 248         print_symbol("RPC: <%s>\n", regs->u_regs[15]);
 249         show_regwindow(regs);
 250 #ifdef CONFIG_SMP
 251         spin_unlock(&regdump_lock);
 252         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
 253                              : : "r" (flags));
 254 #endif
 255 }
 256
 257 #ifdef VERBOSE_SHOWREGS
 258 static void idump_from_user (unsigned int *pc)
 259 {
 260         int i;
 261         int code;
 262
 263         if((((unsigned long) pc) & 3))
 264                 return;
 265
 266         pc -= 3;
 267         for(i = -3; i < 6; i++) {
 268                 get_user(code, pc);
 269                 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
 270                 pc++;
 271         }
 272         printk("\n");
 273 }
 274 #endif
 275
 276 void show_regs(struct pt_regs *regs)
 277 {
 278 #ifdef VERBOSE_SHOWREGS
 279         extern long etrap, etraptl1;
 280 #endif
 281         __show_regs(regs);
 282 #if 0
 283 #ifdef CONFIG_SMP
 284         {
 285                 extern void smp_report_regs(void);
 286
 287                 smp_report_regs();
 288         }
 289 #endif
 290 #endif
 291
 292 #ifdef VERBOSE_SHOWREGS
 293         if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
 294             regs->u_regs[14] >= (long)current - PAGE_SIZE &&
 295             regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
 296                 printk ("*********parent**********\n");
 297                 __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
 298                 idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
 299                 printk ("*********endpar**********\n");
 300         }
 301 #endif
 302 }
 303
 304 unsigned long thread_saved_pc(struct task_struct *tsk)
 305 {
 306         struct thread_info *ti = task_thread_info(tsk);
 307         unsigned long ret = 0xdeadbeefUL;
 308
 309         if (ti && ti->ksp) {
 310                 unsigned long *sp;
 311                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
 312                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
 313                     sp[14]) {
 314                         unsigned long *fp;
 315                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
 316                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
 317                                 ret = fp[15];
 318                 }
 319         }
 320         return ret;
 321 }
 322
 323 /* Free current thread data structures etc.. */
 324 void exit_thread(void)
 325 {
 326         struct thread_info *t = current_thread_info();
 327
 328         if (t->utraps) {
 329                 if (t->utraps[0] < 2)
 330                         kfree (t->utraps);
 331                 else
 332                         t->utraps[0]--;
 333         }
 334
 335         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 336                 t->user_cntd0 = t->user_cntd1 = NULL;
 337                 t->pcr_reg = 0;
 338                 write_pcr(0);
 339         }
 340 }
 341
 342 void flush_thread(void)
 343 {
 344         struct thread_info *t = current_thread_info();
 345         struct mm_struct *mm;
 346
 347         if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
 348                 clear_ti_thread_flag(t, TIF_ABI_PENDING);
 349                 if (test_ti_thread_flag(t, TIF_32BIT))
 350                         clear_ti_thread_flag(t, TIF_32BIT);
 351                 else
 352                         set_ti_thread_flag(t, TIF_32BIT);
 353         }
 354
 355         mm = t->task->mm;
 356         if (mm)
 357                 tsb_context_switch(mm);
 358
 359         set_thread_wsaved(0);
 360
 361         /* Turn off performance counters if on. */
 362         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 363                 t->user_cntd0 = t->user_cntd1 = NULL;
 364                 t->pcr_reg = 0;
 365                 write_pcr(0);
 366         }
 367
 368         /* Clear FPU register state. */
 369         t->fpsaved[0] = 0;
 370
 371         if (get_thread_current_ds() != ASI_AIUS)
 372                 set_fs(USER_DS);
 373
 374         /* Init new signal delivery disposition. */
 375         clear_thread_flag(TIF_NEWSIGNALS);
 376 }
 377
 378 /* It's a bit more tricky when 64-bit tasks are involved... */
 379 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 380 {
 381         unsigned long fp, distance, rval;
 382
 383         if (!(test_thread_flag(TIF_32BIT))) {
 384                 csp += STACK_BIAS;
 385                 psp += STACK_BIAS;
 386                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 387                 fp += STACK_BIAS;
 388         } else
 389                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 390
 391         /* Now 8-byte align the stack as this is mandatory in the
 392          * Sparc ABI due to how register windows work.  This hides
 393          * the restriction from thread libraries etc.  -DaveM
 394          */
 395         csp &= ~7UL;
 396
 397         distance = fp - psp;
 398         rval = (csp - distance);
 399         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
 400                 rval = 0;
 401         else if (test_thread_flag(TIF_32BIT)) {
 402                 if (put_user(((u32)csp),
 403                              &(((struct reg_window32 __user *)rval)->ins[6])))
 404                         rval = 0;
 405         } else {
 406                 if (put_user(((u64)csp - STACK_BIAS),
 407                              &(((struct reg_window __user *)rval)->ins[6])))
 408                         rval = 0;
 409                 else
 410                         rval = rval - STACK_BIAS;
 411         }
 412
 413         return rval;
 414 }
 415
 416 /* Standard stuff. */
 417 static inline void shift_window_buffer(int first_win, int last_win,
 418                                        struct thread_info *t)
 419 {
 420         int i;
 421
 422         for (i = first_win; i < last_win; i++) {
 423                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
 424                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
 425                        sizeof(struct reg_window));
 426         }
 427 }
 428
 429 void synchronize_user_stack(void)
 430 {
 431         struct thread_info *t = current_thread_info();
 432         unsigned long window;
 433
 434         flush_user_windows();
 435         if ((window = get_thread_wsaved()) != 0) {
 436                 int winsize = sizeof(struct reg_window);
 437                 int bias = 0;
 438
 439                 if (test_thread_flag(TIF_32BIT))
 440                         winsize = sizeof(struct reg_window32);
 441                 else
 442                         bias = STACK_BIAS;
 443
 444                 window -= 1;
 445                 do {
 446                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 447                         struct reg_window *rwin = &t->reg_window[window];
 448
 449                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
 450                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
 451                                 set_thread_wsaved(get_thread_wsaved() - 1);
 452                         }
 453                 } while (window--);
 454         }
 455 }
 456
 457 static void stack_unaligned(unsigned long sp)
 458 {
 459         siginfo_t info;
 460
 461         info.si_signo = SIGBUS;
 462         info.si_errno = 0;
 463         info.si_code = BUS_ADRALN;
 464         info.si_addr = (void __user *) sp;
 465         info.si_trapno = 0;
 466         force_sig_info(SIGBUS, &info, current);
 467 }
 468
 469 void fault_in_user_windows(void)
 470 {
 471         struct thread_info *t = current_thread_info();
 472         unsigned long window;
 473         int winsize = sizeof(struct reg_window);
 474         int bias = 0;
 475
 476         if (test_thread_flag(TIF_32BIT))
 477                 winsize = sizeof(struct reg_window32);
 478         else
 479                 bias = STACK_BIAS;
 480
 481         flush_user_windows();
 482         window = get_thread_wsaved();
 483
 484         if (likely(window != 0)) {
 485                 window -= 1;
 486                 do {
 487                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 488                         struct reg_window *rwin = &t->reg_window[window];
 489
 490                         if (unlikely(sp & 0x7UL))
 491                                 stack_unaligned(sp);
 492
 493                         if (unlikely(copy_to_user((char __user *)sp,
 494                                                   rwin, winsize)))
 495                                 goto barf;
 496                 } while (window--);
 497         }
 498         set_thread_wsaved(0);
 499         return;
 500
 501 barf:
 502         set_thread_wsaved(window + 1);
 503         do_exit(SIGILL);
 504 }
 505
 506 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 507                               unsigned long stack_start,
 508                               struct pt_regs *regs,
 509                               unsigned long stack_size)
 510 {
 511         int __user *parent_tid_ptr, *child_tid_ptr;
 512
 513 #ifdef CONFIG_COMPAT
 514         if (test_thread_flag(TIF_32BIT)) {
 515                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 516                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 517         } else
 518 #endif
 519         {
 520                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 521                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 522         }
 523
 524         return do_fork(clone_flags, stack_start,
 525                        regs, stack_size,
 526                        parent_tid_ptr, child_tid_ptr);
 527 }
 528
 529 /* Copy a Sparc thread.  The fork() return value conventions
 530  * under SunOS are nothing short of bletcherous:
 531  * Parent -->  %o0 == childs  pid, %o1 == 0
 532  * Child  -->  %o0 == parents pid, %o1 == 1
 533  */
 534 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 535                 unsigned long unused,
 536                 struct task_struct *p, struct pt_regs *regs)
 537 {
 538         struct thread_info *t = task_thread_info(p);
 539         char *child_trap_frame;
 540
 541         /* Calculate offset to stack_frame & pt_regs */
 542         child_trap_frame = task_stack_page(p) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
 543         memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
 544
 545         t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
 546                 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
 547         t->new_child = 1;
 548         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 549         t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
 550         t->fpsaved[0] = 0;
 551
 552         if (regs->tstate & TSTATE_PRIV) {
 553                 /* Special case, if we are spawning a kernel thread from
 554                  * a userspace task (via KMOD, NFS, or similar) we must
 555                  * disable performance counters in the child because the
 556                  * address space and protection realm are changing.
 557                  */
 558                 if (t->flags & _TIF_PERFCTR) {
 559                         t->user_cntd0 = t->user_cntd1 = NULL;
 560                         t->pcr_reg = 0;
 561                         t->flags &= ~_TIF_PERFCTR;
 562                 }
 563                 t->kregs->u_regs[UREG_FP] = t->ksp;
 564                 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
 565                 flush_register_windows();
 566                 memcpy((void *)(t->ksp + STACK_BIAS),
 567                        (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
 568                        sizeof(struct sparc_stackf));
 569                 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
 570                 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
 571         } else {
 572                 if (t->flags & _TIF_32BIT) {
 573                         sp &= 0x00000000ffffffffUL;
 574                         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 575                 }
 576                 t->kregs->u_regs[UREG_FP] = sp;
 577                 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
 578                 if (sp != regs->u_regs[UREG_FP]) {
 579                         unsigned long csp;
 580
 581                         csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 582                         if (!csp)
 583                                 return -EFAULT;
 584                         t->kregs->u_regs[UREG_FP] = csp;
 585                 }
 586                 if (t->utraps)
 587                         t->utraps[0]++;
 588         }
 589
 590         /* Set the return value for the child. */
 591         t->kregs->u_regs[UREG_I0] = current->pid;
 592         t->kregs->u_regs[UREG_I1] = 1;
 593
 594         /* Set the second return value for the parent. */
 595         regs->u_regs[UREG_I1] = 0;
 596
 597         if (clone_flags & CLONE_SETTLS)
 598                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 599
 600         return 0;
 601 }
 602
 603 /*
 604  * This is the mechanism for creating a new kernel thread.
 605  *
 606  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 607  * who haven't done an "execve()") should use this: it will work within
 608  * a system call from a "real" process, but the process memory space will
 609  * not be freed until both the parent and the child have exited.
 610  */
 611 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 612 {
 613         long retval;
 614
 615         /* If the parent runs before fn(arg) is called by the child,
 616          * the input registers of this function can be clobbered.
 617          * So we stash 'fn' and 'arg' into global registers which
 618          * will not be modified by the parent.
 619          */
 620         __asm__ __volatile__("mov %4, %%g2\n\t"    /* Save FN into global */
 621                              "mov %5, %%g3\n\t"    /* Save ARG into global */
 622                              "mov %1, %%g1\n\t"    /* Clone syscall nr. */
 623                              "mov %2, %%o0\n\t"    /* Clone flags. */
 624                              "mov 0, %%o1\n\t"     /* usp arg == 0 */
 625                              "t 0x6d\n\t"          /* Linux/Sparc clone(). */
 626                              "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
 627                              " mov %%o0, %0\n\t"
 628                              "jmpl %%g2, %%o7\n\t"   /* Call the function. */
 629                              " mov %%g3, %%o0\n\t"   /* Set arg in delay. */
 630                              "mov %3, %%g1\n\t"
 631                              "t 0x6d\n\t"          /* Linux/Sparc exit(). */
 632                              /* Notreached by child. */
 633                              "1:" :
 634                              "=r" (retval) :
 635                              "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
 636                              "i" (__NR_exit),  "r" (fn), "r" (arg) :
 637                              "g1", "g2", "g3", "o0", "o1", "memory", "cc");
 638         return retval;
 639 }
 640
 641 typedef struct {
 642         union {
 643                 unsigned int    pr_regs[32];
 644                 unsigned long   pr_dregs[16];
 645         } pr_fr;
 646         unsigned int __unused;
 647         unsigned int    pr_fsr;
 648         unsigned char   pr_qcnt;
 649         unsigned char   pr_q_entrysize;
 650         unsigned char   pr_en;
 651         unsigned int    pr_q[64];
 652 } elf_fpregset_t32;
 653
 654 /*
 655  * fill in the fpu structure for a core dump.
 656  */
 657 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 658 {
 659         unsigned long *kfpregs = current_thread_info()->fpregs;
 660         unsigned long fprs = current_thread_info()->fpsaved[0];
 661
 662         if (test_thread_flag(TIF_32BIT)) {
 663                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 664
 665                 if (fprs & FPRS_DL)
 666                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 667                                sizeof(unsigned int) * 32);
 668                 else
 669                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 670                                sizeof(unsigned int) * 32);
 671                 fpregs32->pr_qcnt = 0;
 672                 fpregs32->pr_q_entrysize = 8;
 673                 memset(&fpregs32->pr_q[0], 0,
 674                        (sizeof(unsigned int) * 64));
 675                 if (fprs & FPRS_FEF) {
 676                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 677                         fpregs32->pr_en = 1;
 678                 } else {
 679                         fpregs32->pr_fsr = 0;
 680                         fpregs32->pr_en = 0;
 681                 }
 682         } else {
 683                 if(fprs & FPRS_DL)
 684                         memcpy(&fpregs->pr_regs[0], kfpregs,
 685                                sizeof(unsigned int) * 32);
 686                 else
 687                         memset(&fpregs->pr_regs[0], 0,
 688                                sizeof(unsigned int) * 32);
 689                 if(fprs & FPRS_DU)
 690                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 691                                sizeof(unsigned int) * 32);
 692                 else
 693                         memset(&fpregs->pr_regs[16], 0,
 694                                sizeof(unsigned int) * 32);
 695                 if(fprs & FPRS_FEF) {
 696                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 697                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 698                 } else {
 699                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 700                 }
 701                 fpregs->pr_fprs = fprs;
 702         }
 703         return 1;
 704 }
 705
 706 /*
 707  * sparc_execve() executes a new program after the asm stub has set
 708  * things up for us.  This should basically do what I want it to.
 709  */
 710 asmlinkage int sparc_execve(struct pt_regs *regs)
 711 {
 712         int error, base = 0;
 713         char *filename;
 714
 715         /* User register window flush is done by entry.S */
 716
 717         /* Check for indirect call. */
 718         if (regs->u_regs[UREG_G1] == 0)
 719                 base = 1;
 720
 721         filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
 722         error = PTR_ERR(filename);
 723         if (IS_ERR(filename))
 724                 goto out;
 725         error = do_execve(filename,
 726                           (char __user * __user *)
 727                           regs->u_regs[base + UREG_I1],
 728                           (char __user * __user *)
 729                           regs->u_regs[base + UREG_I2], regs);
 730         putname(filename);
 731         if (!error) {
 732                 fprs_write(0);
 733                 current_thread_info()->xfsr[0] = 0;
 734                 current_thread_info()->fpsaved[0] = 0;
 735                 regs->tstate &= ~TSTATE_PEF;
 736                 task_lock(current);
 737                 current->ptrace &= ~PT_DTRACE;
 738                 task_unlock(current);
 739         }
 740 out:
 741         return error;
 742 }
 743
 744 unsigned long get_wchan(struct task_struct *task)
 745 {
 746         unsigned long pc, fp, bias = 0;
 747         unsigned long thread_info_base;
 748         struct reg_window *rw;
 749         unsigned long ret = 0;
 750         int count = 0;
 751
 752         if (!task || task == current ||
 753             task->state == TASK_RUNNING)
 754                 goto out;
 755
 756         thread_info_base = (unsigned long) task_stack_page(task);
 757         bias = STACK_BIAS;
 758         fp = task_thread_info(task)->ksp + bias;
 759
 760         do {
 761                 /* Bogus frame pointer? */
 762                 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
 763                     fp >= (thread_info_base + THREAD_SIZE))
 764                         break;
 765                 rw = (struct reg_window *) fp;
 766                 pc = rw->ins[7];
 767                 if (!in_sched_functions(pc)) {
 768                         ret = pc;
 769                         goto out;
 770                 }
 771                 fp = rw->ins[6] + bias;
 772         } while (++count < 16);
 773
 774 out:
 775         return ret;
 776 }