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/smp.h>
  22 #include <linux/stddef.h>
  23 #include <linux/ptrace.h>
  24 #include <linux/slab.h>
  25 #include <linux/user.h>
  26 #include <linux/a.out.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
  33 #include <asm/oplib.h>
  34 #include <asm/uaccess.h>
  35 #include <asm/system.h>
  36 #include <asm/page.h>
  37 #include <asm/pgalloc.h>
  38 #include <asm/pgtable.h>
  39 #include <asm/processor.h>
  40 #include <asm/pstate.h>
  41 #include <asm/elf.h>
  42 #include <asm/fpumacro.h>
  43 #include <asm/head.h>
  44 #include <asm/cpudata.h>
  45 #include <asm/mmu_context.h>
  46 #include <asm/unistd.h>
  47 #include <asm/hypervisor.h>
  48 #include <asm/sstate.h>
  49
  50 /* #define VERBOSE_SHOWREGS */
  51
  52 static void sparc64_yield(void)
  53 {
  54         if (tlb_type != hypervisor)
  55                 return;
  56
  57         clear_thread_flag(TIF_POLLING_NRFLAG);
  58         smp_mb__after_clear_bit();
  59
  60         while (!need_resched()) {
  61                 unsigned long pstate;
  62
  63                 /* Disable interrupts. */
  64                 __asm__ __volatile__(
  65                         "rdpr %%pstate, %0\n\t"
  66                         "andn %0, %1, %0\n\t"
  67                         "wrpr %0, %%g0, %%pstate"
  68                         : "=&r" (pstate)
  69                         : "i" (PSTATE_IE));
  70
  71                 if (!need_resched())
  72                         sun4v_cpu_yield();
  73
  74                 /* Re-enable interrupts. */
  75                 __asm__ __volatile__(
  76                         "rdpr %%pstate, %0\n\t"
  77                         "or %0, %1, %0\n\t"
  78                         "wrpr %0, %%g0, %%pstate"
  79                         : "=&r" (pstate)
  80                         : "i" (PSTATE_IE));
  81         }
  82
  83         set_thread_flag(TIF_POLLING_NRFLAG);
  84 }
  85
  86 /* The idle loop on sparc64. */
  87 void cpu_idle(void)
  88 {
  89         set_thread_flag(TIF_POLLING_NRFLAG);
  90
  91         while(1) {
  92                 tick_nohz_stop_sched_tick();
  93                 while (!need_resched())
  94                         sparc64_yield();
  95                 tick_nohz_restart_sched_tick();
  96
  97                 preempt_enable_no_resched();
  98                 schedule();
  99                 preempt_disable();
 100         }
 101 }
 102
 103 extern char reboot_command [];
 104
 105 extern void (*prom_palette)(int);
 106 extern void (*prom_keyboard)(void);
 107
 108 void machine_halt(void)
 109 {
 110         sstate_halt();
 111         if (!serial_console && prom_palette)
 112                 prom_palette (1);
 113         if (prom_keyboard)
 114                 prom_keyboard();
 115         prom_halt();
 116         panic("Halt failed!");
 117 }
 118
 119 void machine_alt_power_off(void)
 120 {
 121         sstate_poweroff();
 122         if (!serial_console && prom_palette)
 123                 prom_palette(1);
 124         if (prom_keyboard)
 125                 prom_keyboard();
 126         prom_halt_power_off();
 127         panic("Power-off failed!");
 128 }
 129
 130 void machine_restart(char * cmd)
 131 {
 132         char *p;
 133
 134         sstate_reboot();
 135         p = strchr (reboot_command, '\n');
 136         if (p) *p = 0;
 137         if (!serial_console && prom_palette)
 138                 prom_palette (1);
 139         if (prom_keyboard)
 140                 prom_keyboard();
 141         if (cmd)
 142                 prom_reboot(cmd);
 143         if (*reboot_command)
 144                 prom_reboot(reboot_command);
 145         prom_reboot("");
 146         panic("Reboot failed!");
 147 }
 148
 149 #ifdef CONFIG_COMPAT
 150 static void show_regwindow32(struct pt_regs *regs)
 151 {
 152         struct reg_window32 __user *rw;
 153         struct reg_window32 r_w;
 154         mm_segment_t old_fs;
 155
 156         __asm__ __volatile__ ("flushw");
 157         rw = compat_ptr((unsigned)regs->u_regs[14]);
 158         old_fs = get_fs();
 159         set_fs (USER_DS);
 160         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 161                 set_fs (old_fs);
 162                 return;
 163         }
 164
 165         set_fs (old_fs);
 166         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
 167                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
 168                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
 169                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
 170         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
 171                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
 172                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
 173                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
 174 }
 175 #else
 176 #define show_regwindow32(regs)  do { } while (0)
 177 #endif
 178
 179 static void show_regwindow(struct pt_regs *regs)
 180 {
 181         struct reg_window __user *rw;
 182         struct reg_window *rwk;
 183         struct reg_window r_w;
 184         mm_segment_t old_fs;
 185
 186         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 187                 __asm__ __volatile__ ("flushw");
 188                 rw = (struct reg_window __user *)
 189                         (regs->u_regs[14] + STACK_BIAS);
 190                 rwk = (struct reg_window *)
 191                         (regs->u_regs[14] + STACK_BIAS);
 192                 if (!(regs->tstate & TSTATE_PRIV)) {
 193                         old_fs = get_fs();
 194                         set_fs (USER_DS);
 195                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 196                                 set_fs (old_fs);
 197                                 return;
 198                         }
 199                         rwk = &r_w;
 200                         set_fs (old_fs);
 201                 }
 202         } else {
 203                 show_regwindow32(regs);
 204                 return;
 205         }
 206         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 207                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 208         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 209                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 210         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 211                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 212         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 213                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 214         if (regs->tstate & TSTATE_PRIV)
 215                 print_symbol("I7: <%s>\n", rwk->ins[7]);
 216 }
 217
 218 void show_stackframe(struct sparc_stackf *sf)
 219 {
 220         unsigned long size;
 221         unsigned long *stk;
 222         int i;
 223
 224         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n"
 225                "l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 226                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
 227                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 228         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n"
 229                "i4: %016lx i5: %016lx fp: %016lx ret_pc: %016lx\n",
 230                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
 231                sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
 232         printk("sp: %016lx x0: %016lx x1: %016lx x2: %016lx\n"
 233                "x3: %016lx x4: %016lx x5: %016lx xx: %016lx\n",
 234                (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
 235                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 236                sf->xxargs[0]);
 237         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 238         size -= STACKFRAME_SZ;
 239         stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
 240         i = 0;
 241         do {
 242                 printk("s%d: %016lx\n", i++, *stk++);
 243         } while ((size -= sizeof(unsigned long)));
 244 }
 245
 246 void show_stackframe32(struct sparc_stackf32 *sf)
 247 {
 248         unsigned long size;
 249         unsigned *stk;
 250         int i;
 251
 252         printk("l0: %08x l1: %08x l2: %08x l3: %08x\n",
 253                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3]);
 254         printk("l4: %08x l5: %08x l6: %08x l7: %08x\n",
 255                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 256         printk("i0: %08x i1: %08x i2: %08x i3: %08x\n",
 257                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3]);
 258         printk("i4: %08x i5: %08x fp: %08x ret_pc: %08x\n",
 259                sf->ins[4], sf->ins[5], sf->fp, sf->callers_pc);
 260         printk("sp: %08x x0: %08x x1: %08x x2: %08x\n"
 261                "x3: %08x x4: %08x x5: %08x xx: %08x\n",
 262                sf->structptr, sf->xargs[0], sf->xargs[1],
 263                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 264                sf->xxargs[0]);
 265         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 266         size -= STACKFRAME32_SZ;
 267         stk = (unsigned *)((unsigned long)sf + STACKFRAME32_SZ);
 268         i = 0;
 269         do {
 270                 printk("s%d: %08x\n", i++, *stk++);
 271         } while ((size -= sizeof(unsigned)));
 272 }
 273
 274 #ifdef CONFIG_SMP
 275 static DEFINE_SPINLOCK(regdump_lock);
 276 #endif
 277
 278 void __show_regs(struct pt_regs * regs)
 279 {
 280 #ifdef CONFIG_SMP
 281         unsigned long flags;
 282
 283         /* Protect against xcall ipis which might lead to livelock on the lock */
 284         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 285                              "wrpr      %0, %1, %%pstate"
 286                              : "=r" (flags)
 287                              : "i" (PSTATE_IE));
 288         spin_lock(&regdump_lock);
 289 #endif
 290         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 291                regs->tpc, regs->tnpc, regs->y, print_tainted());
 292         print_symbol("TPC: <%s>\n", regs->tpc);
 293         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 294                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 295                regs->u_regs[3]);
 296         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 297                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 298                regs->u_regs[7]);
 299         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 300                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 301                regs->u_regs[11]);
 302         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 303                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 304                regs->u_regs[15]);
 305         print_symbol("RPC: <%s>\n", regs->u_regs[15]);
 306         show_regwindow(regs);
 307 #ifdef CONFIG_SMP
 308         spin_unlock(&regdump_lock);
 309         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
 310                              : : "r" (flags));
 311 #endif
 312 }
 313
 314 #ifdef VERBOSE_SHOWREGS
 315 static void idump_from_user (unsigned int *pc)
 316 {
 317         int i;
 318         int code;
 319
 320         if((((unsigned long) pc) & 3))
 321                 return;
 322
 323         pc -= 3;
 324         for(i = -3; i < 6; i++) {
 325                 get_user(code, pc);
 326                 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
 327                 pc++;
 328         }
 329         printk("\n");
 330 }
 331 #endif
 332
 333 void show_regs(struct pt_regs *regs)
 334 {
 335 #ifdef VERBOSE_SHOWREGS
 336         extern long etrap, etraptl1;
 337 #endif
 338         __show_regs(regs);
 339 #if 0
 340 #ifdef CONFIG_SMP
 341         {
 342                 extern void smp_report_regs(void);
 343
 344                 smp_report_regs();
 345         }
 346 #endif
 347 #endif
 348
 349 #ifdef VERBOSE_SHOWREGS
 350         if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
 351             regs->u_regs[14] >= (long)current - PAGE_SIZE &&
 352             regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
 353                 printk ("*********parent**********\n");
 354                 __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
 355                 idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
 356                 printk ("*********endpar**********\n");
 357         }
 358 #endif
 359 }
 360
 361 void show_regs32(struct pt_regs32 *regs)
 362 {
 363         printk("PSR: %08x PC: %08x NPC: %08x Y: %08x    %s\n", regs->psr,
 364                regs->pc, regs->npc, regs->y, print_tainted());
 365         printk("g0: %08x g1: %08x g2: %08x g3: %08x ",
 366                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 367                regs->u_regs[3]);
 368         printk("g4: %08x g5: %08x g6: %08x g7: %08x\n",
 369                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 370                regs->u_regs[7]);
 371         printk("o0: %08x o1: %08x o2: %08x o3: %08x ",
 372                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 373                regs->u_regs[11]);
 374         printk("o4: %08x o5: %08x sp: %08x ret_pc: %08x\n",
 375                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 376                regs->u_regs[15]);
 377 }
 378
 379 unsigned long thread_saved_pc(struct task_struct *tsk)
 380 {
 381         struct thread_info *ti = task_thread_info(tsk);
 382         unsigned long ret = 0xdeadbeefUL;
 383
 384         if (ti && ti->ksp) {
 385                 unsigned long *sp;
 386                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
 387                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
 388                     sp[14]) {
 389                         unsigned long *fp;
 390                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
 391                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
 392                                 ret = fp[15];
 393                 }
 394         }
 395         return ret;
 396 }
 397
 398 /* Free current thread data structures etc.. */
 399 void exit_thread(void)
 400 {
 401         struct thread_info *t = current_thread_info();
 402
 403         if (t->utraps) {
 404                 if (t->utraps[0] < 2)
 405                         kfree (t->utraps);
 406                 else
 407                         t->utraps[0]--;
 408         }
 409
 410         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 411                 t->user_cntd0 = t->user_cntd1 = NULL;
 412                 t->pcr_reg = 0;
 413                 write_pcr(0);
 414         }
 415 }
 416
 417 void flush_thread(void)
 418 {
 419         struct thread_info *t = current_thread_info();
 420         struct mm_struct *mm;
 421
 422         if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
 423                 clear_ti_thread_flag(t, TIF_ABI_PENDING);
 424                 if (test_ti_thread_flag(t, TIF_32BIT))
 425                         clear_ti_thread_flag(t, TIF_32BIT);
 426                 else
 427                         set_ti_thread_flag(t, TIF_32BIT);
 428         }
 429
 430         mm = t->task->mm;
 431         if (mm)
 432                 tsb_context_switch(mm);
 433
 434         set_thread_wsaved(0);
 435
 436         /* Turn off performance counters if on. */
 437         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 438                 t->user_cntd0 = t->user_cntd1 = NULL;
 439                 t->pcr_reg = 0;
 440                 write_pcr(0);
 441         }
 442
 443         /* Clear FPU register state. */
 444         t->fpsaved[0] = 0;
 445
 446         if (get_thread_current_ds() != ASI_AIUS)
 447                 set_fs(USER_DS);
 448
 449         /* Init new signal delivery disposition. */
 450         clear_thread_flag(TIF_NEWSIGNALS);
 451 }
 452
 453 /* It's a bit more tricky when 64-bit tasks are involved... */
 454 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 455 {
 456         unsigned long fp, distance, rval;
 457
 458         if (!(test_thread_flag(TIF_32BIT))) {
 459                 csp += STACK_BIAS;
 460                 psp += STACK_BIAS;
 461                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 462                 fp += STACK_BIAS;
 463         } else
 464                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 465
 466         /* Now 8-byte align the stack as this is mandatory in the
 467          * Sparc ABI due to how register windows work.  This hides
 468          * the restriction from thread libraries etc.  -DaveM
 469          */
 470         csp &= ~7UL;
 471
 472         distance = fp - psp;
 473         rval = (csp - distance);
 474         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
 475                 rval = 0;
 476         else if (test_thread_flag(TIF_32BIT)) {
 477                 if (put_user(((u32)csp),
 478                              &(((struct reg_window32 __user *)rval)->ins[6])))
 479                         rval = 0;
 480         } else {
 481                 if (put_user(((u64)csp - STACK_BIAS),
 482                              &(((struct reg_window __user *)rval)->ins[6])))
 483                         rval = 0;
 484                 else
 485                         rval = rval - STACK_BIAS;
 486         }
 487
 488         return rval;
 489 }
 490
 491 /* Standard stuff. */
 492 static inline void shift_window_buffer(int first_win, int last_win,
 493                                        struct thread_info *t)
 494 {
 495         int i;
 496
 497         for (i = first_win; i < last_win; i++) {
 498                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
 499                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
 500                        sizeof(struct reg_window));
 501         }
 502 }
 503
 504 void synchronize_user_stack(void)
 505 {
 506         struct thread_info *t = current_thread_info();
 507         unsigned long window;
 508
 509         flush_user_windows();
 510         if ((window = get_thread_wsaved()) != 0) {
 511                 int winsize = sizeof(struct reg_window);
 512                 int bias = 0;
 513
 514                 if (test_thread_flag(TIF_32BIT))
 515                         winsize = sizeof(struct reg_window32);
 516                 else
 517                         bias = STACK_BIAS;
 518
 519                 window -= 1;
 520                 do {
 521                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 522                         struct reg_window *rwin = &t->reg_window[window];
 523
 524                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
 525                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
 526                                 set_thread_wsaved(get_thread_wsaved() - 1);
 527                         }
 528                 } while (window--);
 529         }
 530 }
 531
 532 static void stack_unaligned(unsigned long sp)
 533 {
 534         siginfo_t info;
 535
 536         info.si_signo = SIGBUS;
 537         info.si_errno = 0;
 538         info.si_code = BUS_ADRALN;
 539         info.si_addr = (void __user *) sp;
 540         info.si_trapno = 0;
 541         force_sig_info(SIGBUS, &info, current);
 542 }
 543
 544 void fault_in_user_windows(void)
 545 {
 546         struct thread_info *t = current_thread_info();
 547         unsigned long window;
 548         int winsize = sizeof(struct reg_window);
 549         int bias = 0;
 550
 551         if (test_thread_flag(TIF_32BIT))
 552                 winsize = sizeof(struct reg_window32);
 553         else
 554                 bias = STACK_BIAS;
 555
 556         flush_user_windows();
 557         window = get_thread_wsaved();
 558
 559         if (likely(window != 0)) {
 560                 window -= 1;
 561                 do {
 562                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 563                         struct reg_window *rwin = &t->reg_window[window];
 564
 565                         if (unlikely(sp & 0x7UL))
 566                                 stack_unaligned(sp);
 567
 568                         if (unlikely(copy_to_user((char __user *)sp,
 569                                                   rwin, winsize)))
 570                                 goto barf;
 571                 } while (window--);
 572         }
 573         set_thread_wsaved(0);
 574         return;
 575
 576 barf:
 577         set_thread_wsaved(window + 1);
 578         do_exit(SIGILL);
 579 }
 580
 581 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 582                               unsigned long stack_start,
 583                               struct pt_regs *regs,
 584                               unsigned long stack_size)
 585 {
 586         int __user *parent_tid_ptr, *child_tid_ptr;
 587
 588 #ifdef CONFIG_COMPAT
 589         if (test_thread_flag(TIF_32BIT)) {
 590                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 591                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 592         } else
 593 #endif
 594         {
 595                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 596                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 597         }
 598
 599         return do_fork(clone_flags, stack_start,
 600                        regs, stack_size,
 601                        parent_tid_ptr, child_tid_ptr);
 602 }
 603
 604 /* Copy a Sparc thread.  The fork() return value conventions
 605  * under SunOS are nothing short of bletcherous:
 606  * Parent -->  %o0 == childs  pid, %o1 == 0
 607  * Child  -->  %o0 == parents pid, %o1 == 1
 608  */
 609 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 610                 unsigned long unused,
 611                 struct task_struct *p, struct pt_regs *regs)
 612 {
 613         struct thread_info *t = task_thread_info(p);
 614         char *child_trap_frame;
 615
 616         /* Calculate offset to stack_frame & pt_regs */
 617         child_trap_frame = task_stack_page(p) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
 618         memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
 619
 620         t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
 621                 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
 622         t->new_child = 1;
 623         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 624         t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
 625         t->fpsaved[0] = 0;
 626
 627         if (regs->tstate & TSTATE_PRIV) {
 628                 /* Special case, if we are spawning a kernel thread from
 629                  * a userspace task (via KMOD, NFS, or similar) we must
 630                  * disable performance counters in the child because the
 631                  * address space and protection realm are changing.
 632                  */
 633                 if (t->flags & _TIF_PERFCTR) {
 634                         t->user_cntd0 = t->user_cntd1 = NULL;
 635                         t->pcr_reg = 0;
 636                         t->flags &= ~_TIF_PERFCTR;
 637                 }
 638                 t->kregs->u_regs[UREG_FP] = t->ksp;
 639                 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
 640                 flush_register_windows();
 641                 memcpy((void *)(t->ksp + STACK_BIAS),
 642                        (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
 643                        sizeof(struct sparc_stackf));
 644                 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
 645                 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
 646         } else {
 647                 if (t->flags & _TIF_32BIT) {
 648                         sp &= 0x00000000ffffffffUL;
 649                         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 650                 }
 651                 t->kregs->u_regs[UREG_FP] = sp;
 652                 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
 653                 if (sp != regs->u_regs[UREG_FP]) {
 654                         unsigned long csp;
 655
 656                         csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 657                         if (!csp)
 658                                 return -EFAULT;
 659                         t->kregs->u_regs[UREG_FP] = csp;
 660                 }
 661                 if (t->utraps)
 662                         t->utraps[0]++;
 663         }
 664
 665         /* Set the return value for the child. */
 666         t->kregs->u_regs[UREG_I0] = current->pid;
 667         t->kregs->u_regs[UREG_I1] = 1;
 668
 669         /* Set the second return value for the parent. */
 670         regs->u_regs[UREG_I1] = 0;
 671
 672         if (clone_flags & CLONE_SETTLS)
 673                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 674
 675         return 0;
 676 }
 677
 678 /*
 679  * This is the mechanism for creating a new kernel thread.
 680  *
 681  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 682  * who haven't done an "execve()") should use this: it will work within
 683  * a system call from a "real" process, but the process memory space will
 684  * not be freed until both the parent and the child have exited.
 685  */
 686 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 687 {
 688         long retval;
 689
 690         /* If the parent runs before fn(arg) is called by the child,
 691          * the input registers of this function can be clobbered.
 692          * So we stash 'fn' and 'arg' into global registers which
 693          * will not be modified by the parent.
 694          */
 695         __asm__ __volatile__("mov %4, %%g2\n\t"    /* Save FN into global */
 696                              "mov %5, %%g3\n\t"    /* Save ARG into global */
 697                              "mov %1, %%g1\n\t"    /* Clone syscall nr. */
 698                              "mov %2, %%o0\n\t"    /* Clone flags. */
 699                              "mov 0, %%o1\n\t"     /* usp arg == 0 */
 700                              "t 0x6d\n\t"          /* Linux/Sparc clone(). */
 701                              "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
 702                              " mov %%o0, %0\n\t"
 703                              "jmpl %%g2, %%o7\n\t"   /* Call the function. */
 704                              " mov %%g3, %%o0\n\t"   /* Set arg in delay. */
 705                              "mov %3, %%g1\n\t"
 706                              "t 0x6d\n\t"          /* Linux/Sparc exit(). */
 707                              /* Notreached by child. */
 708                              "1:" :
 709                              "=r" (retval) :
 710                              "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
 711                              "i" (__NR_exit),  "r" (fn), "r" (arg) :
 712                              "g1", "g2", "g3", "o0", "o1", "memory", "cc");
 713         return retval;
 714 }
 715
 716 /*
 717  * fill in the user structure for a core dump..
 718  */
 719 void dump_thread(struct pt_regs * regs, struct user * dump)
 720 {
 721         /* Only should be used for SunOS and ancient a.out
 722          * SparcLinux binaries...  Not worth implementing.
 723          */
 724         memset(dump, 0, sizeof(struct user));
 725 }
 726
 727 typedef struct {
 728         union {
 729                 unsigned int    pr_regs[32];
 730                 unsigned long   pr_dregs[16];
 731         } pr_fr;
 732         unsigned int __unused;
 733         unsigned int    pr_fsr;
 734         unsigned char   pr_qcnt;
 735         unsigned char   pr_q_entrysize;
 736         unsigned char   pr_en;
 737         unsigned int    pr_q[64];
 738 } elf_fpregset_t32;
 739
 740 /*
 741  * fill in the fpu structure for a core dump.
 742  */
 743 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 744 {
 745         unsigned long *kfpregs = current_thread_info()->fpregs;
 746         unsigned long fprs = current_thread_info()->fpsaved[0];
 747
 748         if (test_thread_flag(TIF_32BIT)) {
 749                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 750
 751                 if (fprs & FPRS_DL)
 752                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 753                                sizeof(unsigned int) * 32);
 754                 else
 755                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 756                                sizeof(unsigned int) * 32);
 757                 fpregs32->pr_qcnt = 0;
 758                 fpregs32->pr_q_entrysize = 8;
 759                 memset(&fpregs32->pr_q[0], 0,
 760                        (sizeof(unsigned int) * 64));
 761                 if (fprs & FPRS_FEF) {
 762                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 763                         fpregs32->pr_en = 1;
 764                 } else {
 765                         fpregs32->pr_fsr = 0;
 766                         fpregs32->pr_en = 0;
 767                 }
 768         } else {
 769                 if(fprs & FPRS_DL)
 770                         memcpy(&fpregs->pr_regs[0], kfpregs,
 771                                sizeof(unsigned int) * 32);
 772                 else
 773                         memset(&fpregs->pr_regs[0], 0,
 774                                sizeof(unsigned int) * 32);
 775                 if(fprs & FPRS_DU)
 776                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 777                                sizeof(unsigned int) * 32);
 778                 else
 779                         memset(&fpregs->pr_regs[16], 0,
 780                                sizeof(unsigned int) * 32);
 781                 if(fprs & FPRS_FEF) {
 782                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 783                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 784                 } else {
 785                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 786                 }
 787                 fpregs->pr_fprs = fprs;
 788         }
 789         return 1;
 790 }
 791
 792 /*
 793  * sparc_execve() executes a new program after the asm stub has set
 794  * things up for us.  This should basically do what I want it to.
 795  */
 796 asmlinkage int sparc_execve(struct pt_regs *regs)
 797 {
 798         int error, base = 0;
 799         char *filename;
 800
 801         /* User register window flush is done by entry.S */
 802
 803         /* Check for indirect call. */
 804         if (regs->u_regs[UREG_G1] == 0)
 805                 base = 1;
 806
 807         filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
 808         error = PTR_ERR(filename);
 809         if (IS_ERR(filename))
 810                 goto out;
 811         error = do_execve(filename,
 812                           (char __user * __user *)
 813                           regs->u_regs[base + UREG_I1],
 814                           (char __user * __user *)
 815                           regs->u_regs[base + UREG_I2], regs);
 816         putname(filename);
 817         if (!error) {
 818                 fprs_write(0);
 819                 current_thread_info()->xfsr[0] = 0;
 820                 current_thread_info()->fpsaved[0] = 0;
 821                 regs->tstate &= ~TSTATE_PEF;
 822                 task_lock(current);
 823                 current->ptrace &= ~PT_DTRACE;
 824                 task_unlock(current);
 825         }
 826 out:
 827         return error;
 828 }
 829
 830 unsigned long get_wchan(struct task_struct *task)
 831 {
 832         unsigned long pc, fp, bias = 0;
 833         unsigned long thread_info_base;
 834         struct reg_window *rw;
 835         unsigned long ret = 0;
 836         int count = 0;
 837
 838         if (!task || task == current ||
 839             task->state == TASK_RUNNING)
 840                 goto out;
 841
 842         thread_info_base = (unsigned long) task_stack_page(task);
 843         bias = STACK_BIAS;
 844         fp = task_thread_info(task)->ksp + bias;
 845
 846         do {
 847                 /* Bogus frame pointer? */
 848                 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
 849                     fp >= (thread_info_base + THREAD_SIZE))
 850                         break;
 851                 rw = (struct reg_window *) fp;
 852                 pc = rw->ins[7];
 853                 if (!in_sched_functions(pc)) {
 854                         ret = pc;
 855                         goto out;
 856                 }
 857                 fp = rw->ins[6] + bias;
 858         } while (++count < 16);
 859
 860 out:
 861         return ret;
 862 }