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/config.h>
  16 #include <linux/errno.h>
  17 #include <linux/module.h>
  18 #include <linux/sched.h>
  19 #include <linux/kernel.h>
  20 #include <linux/kallsyms.h>
  21 #include <linux/mm.h>
  22 #include <linux/smp.h>
  23 #include <linux/smp_lock.h>
  24 #include <linux/stddef.h>
  25 #include <linux/ptrace.h>
  26 #include <linux/slab.h>
  27 #include <linux/user.h>
  28 #include <linux/a.out.h>
  29 #include <linux/config.h>
  30 #include <linux/reboot.h>
  31 #include <linux/delay.h>
  32 #include <linux/compat.h>
  33 #include <linux/init.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/unistd.h>
  48
  49 /* #define VERBOSE_SHOWREGS */
  50
  51 /*
  52  * Nothing special yet...
  53  */
  54 void default_idle(void)
  55 {
  56 }
  57
  58 #ifndef CONFIG_SMP
  59
  60 /*
  61  * the idle loop on a Sparc... ;)
  62  */
  63 void cpu_idle(void)
  64 {
  65         /* endless idle loop with no priority at all */
  66         for (;;) {
  67                 /* If current->work.need_resched is zero we should really
  68                  * setup for a system wakup event and execute a shutdown
  69                  * instruction.
  70                  *
  71                  * But this requires writing back the contents of the
  72                  * L2 cache etc. so implement this later. -DaveM
  73                  */
  74                 while (!need_resched())
  75                         barrier();
  76
  77                 schedule();
  78                 check_pgt_cache();
  79         }
  80 }
  81
  82 #else
  83
  84 /*
  85  * the idle loop on a UltraMultiPenguin...
  86  */
  87 #define idle_me_harder()        (cpu_data(smp_processor_id()).idle_volume += 1)
  88 #define unidle_me()             (cpu_data(smp_processor_id()).idle_volume = 0)
  89 void cpu_idle(void)
  90 {
  91         set_thread_flag(TIF_POLLING_NRFLAG);
  92         while(1) {
  93                 if (need_resched()) {
  94                         unidle_me();
  95                         clear_thread_flag(TIF_POLLING_NRFLAG);
  96                         schedule();
  97                         set_thread_flag(TIF_POLLING_NRFLAG);
  98                         check_pgt_cache();
  99                 }
 100                 idle_me_harder();
 101
 102                 /* The store ordering is so that IRQ handlers on
 103                  * other cpus see our increasing idleness for the buddy
 104                  * redistribution algorithm.  -DaveM
 105                  */
 106                 membar("#StoreStore | #StoreLoad");
 107         }
 108 }
 109
 110 #endif
 111
 112 extern char reboot_command [];
 113
 114 extern void (*prom_palette)(int);
 115 extern void (*prom_keyboard)(void);
 116
 117 void machine_halt(void)
 118 {
 119         if (!serial_console && prom_palette)
 120                 prom_palette (1);
 121         if (prom_keyboard)
 122                 prom_keyboard();
 123         prom_halt();
 124         panic("Halt failed!");
 125 }
 126
 127 void machine_alt_power_off(void)
 128 {
 129         if (!serial_console && prom_palette)
 130                 prom_palette(1);
 131         if (prom_keyboard)
 132                 prom_keyboard();
 133         prom_halt_power_off();
 134         panic("Power-off failed!");
 135 }
 136
 137 void machine_restart(char * cmd)
 138 {
 139         char *p;
 140
 141         p = strchr (reboot_command, '\n');
 142         if (p) *p = 0;
 143         if (!serial_console && prom_palette)
 144                 prom_palette (1);
 145         if (prom_keyboard)
 146                 prom_keyboard();
 147         if (cmd)
 148                 prom_reboot(cmd);
 149         if (*reboot_command)
 150                 prom_reboot(reboot_command);
 151         prom_reboot("");
 152         panic("Reboot failed!");
 153 }
 154
 155 static void show_regwindow32(struct pt_regs *regs)
 156 {
 157         struct reg_window32 __user *rw;
 158         struct reg_window32 r_w;
 159         mm_segment_t old_fs;
 160
 161         __asm__ __volatile__ ("flushw");
 162         rw = compat_ptr((unsigned)regs->u_regs[14]);
 163         old_fs = get_fs();
 164         set_fs (USER_DS);
 165         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 166                 set_fs (old_fs);
 167                 return;
 168         }
 169
 170         set_fs (old_fs);
 171         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
 172                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
 173                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
 174                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
 175         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
 176                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
 177                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
 178                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
 179 }
 180
 181 static void show_regwindow(struct pt_regs *regs)
 182 {
 183         struct reg_window __user *rw;
 184         struct reg_window *rwk;
 185         struct reg_window r_w;
 186         mm_segment_t old_fs;
 187
 188         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 189                 __asm__ __volatile__ ("flushw");
 190                 rw = (struct reg_window __user *)
 191                         (regs->u_regs[14] + STACK_BIAS);
 192                 rwk = (struct reg_window *)
 193                         (regs->u_regs[14] + STACK_BIAS);
 194                 if (!(regs->tstate & TSTATE_PRIV)) {
 195                         old_fs = get_fs();
 196                         set_fs (USER_DS);
 197                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 198                                 set_fs (old_fs);
 199                                 return;
 200                         }
 201                         rwk = &r_w;
 202                         set_fs (old_fs);
 203                 }
 204         } else {
 205                 show_regwindow32(regs);
 206                 return;
 207         }
 208         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 209                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 210         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 211                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 212         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 213                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 214         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 215                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 216         if (regs->tstate & TSTATE_PRIV)
 217                 print_symbol("I7: <%s>\n", rwk->ins[7]);
 218 }
 219
 220 void show_stackframe(struct sparc_stackf *sf)
 221 {
 222         unsigned long size;
 223         unsigned long *stk;
 224         int i;
 225
 226         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n"
 227                "l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 228                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
 229                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 230         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n"
 231                "i4: %016lx i5: %016lx fp: %016lx ret_pc: %016lx\n",
 232                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
 233                sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
 234         printk("sp: %016lx x0: %016lx x1: %016lx x2: %016lx\n"
 235                "x3: %016lx x4: %016lx x5: %016lx xx: %016lx\n",
 236                (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
 237                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 238                sf->xxargs[0]);
 239         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 240         size -= STACKFRAME_SZ;
 241         stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
 242         i = 0;
 243         do {
 244                 printk("s%d: %016lx\n", i++, *stk++);
 245         } while ((size -= sizeof(unsigned long)));
 246 }
 247
 248 void show_stackframe32(struct sparc_stackf32 *sf)
 249 {
 250         unsigned long size;
 251         unsigned *stk;
 252         int i;
 253
 254         printk("l0: %08x l1: %08x l2: %08x l3: %08x\n",
 255                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3]);
 256         printk("l4: %08x l5: %08x l6: %08x l7: %08x\n",
 257                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 258         printk("i0: %08x i1: %08x i2: %08x i3: %08x\n",
 259                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3]);
 260         printk("i4: %08x i5: %08x fp: %08x ret_pc: %08x\n",
 261                sf->ins[4], sf->ins[5], sf->fp, sf->callers_pc);
 262         printk("sp: %08x x0: %08x x1: %08x x2: %08x\n"
 263                "x3: %08x x4: %08x x5: %08x xx: %08x\n",
 264                sf->structptr, sf->xargs[0], sf->xargs[1],
 265                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 266                sf->xxargs[0]);
 267         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 268         size -= STACKFRAME32_SZ;
 269         stk = (unsigned *)((unsigned long)sf + STACKFRAME32_SZ);
 270         i = 0;
 271         do {
 272                 printk("s%d: %08x\n", i++, *stk++);
 273         } while ((size -= sizeof(unsigned)));
 274 }
 275
 276 #ifdef CONFIG_SMP
 277 static DEFINE_SPINLOCK(regdump_lock);
 278 #endif
 279
 280 void __show_regs(struct pt_regs * regs)
 281 {
 282 #ifdef CONFIG_SMP
 283         unsigned long flags;
 284
 285         /* Protect against xcall ipis which might lead to livelock on the lock */
 286         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 287                              "wrpr      %0, %1, %%pstate"
 288                              : "=r" (flags)
 289                              : "i" (PSTATE_IE));
 290         spin_lock(&regdump_lock);
 291 #endif
 292         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 293                regs->tpc, regs->tnpc, regs->y, print_tainted());
 294         print_symbol("TPC: <%s>\n", regs->tpc);
 295         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 296                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 297                regs->u_regs[3]);
 298         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 299                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 300                regs->u_regs[7]);
 301         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 302                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 303                regs->u_regs[11]);
 304         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 305                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 306                regs->u_regs[15]);
 307         print_symbol("RPC: <%s>\n", regs->u_regs[15]);
 308         show_regwindow(regs);
 309 #ifdef CONFIG_SMP
 310         spin_unlock(&regdump_lock);
 311         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
 312                              : : "r" (flags));
 313 #endif
 314 }
 315
 316 #ifdef VERBOSE_SHOWREGS
 317 static void idump_from_user (unsigned int *pc)
 318 {
 319         int i;
 320         int code;
 321
 322         if((((unsigned long) pc) & 3))
 323                 return;
 324
 325         pc -= 3;
 326         for(i = -3; i < 6; i++) {
 327                 get_user(code, pc);
 328                 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
 329                 pc++;
 330         }
 331         printk("\n");
 332 }
 333 #endif
 334
 335 void show_regs(struct pt_regs *regs)
 336 {
 337 #ifdef VERBOSE_SHOWREGS
 338         extern long etrap, etraptl1;
 339 #endif
 340         __show_regs(regs);
 341 #ifdef CONFIG_SMP
 342         {
 343                 extern void smp_report_regs(void);
 344
 345                 smp_report_regs();
 346         }
 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 = tsk->thread_info;
 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
 421         if (t->flags & _TIF_ABI_PENDING)
 422                 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
 423
 424         if (t->task->mm) {
 425                 unsigned long pgd_cache = 0UL;
 426                 if (test_thread_flag(TIF_32BIT)) {
 427                         struct mm_struct *mm = t->task->mm;
 428                         pgd_t *pgd0 = &mm->pgd[0];
 429                         pud_t *pud0 = pud_offset(pgd0, 0);
 430
 431                         if (pud_none(*pud0)) {
 432                                 pmd_t *page = pmd_alloc_one(mm, 0);
 433                                 pud_set(pud0, page);
 434                         }
 435                         pgd_cache = get_pgd_cache(pgd0);
 436                 }
 437                 __asm__ __volatile__("stxa %0, [%1] %2\n\t"
 438                                      "membar #Sync"
 439                                      : /* no outputs */
 440                                      : "r" (pgd_cache),
 441                                      "r" (TSB_REG),
 442                                      "i" (ASI_DMMU));
 443         }
 444         set_thread_wsaved(0);
 445
 446         /* Turn off performance counters if on. */
 447         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 448                 t->user_cntd0 = t->user_cntd1 = NULL;
 449                 t->pcr_reg = 0;
 450                 write_pcr(0);
 451         }
 452
 453         /* Clear FPU register state. */
 454         t->fpsaved[0] = 0;
 455
 456         if (get_thread_current_ds() != ASI_AIUS)
 457                 set_fs(USER_DS);
 458
 459         /* Init new signal delivery disposition. */
 460         clear_thread_flag(TIF_NEWSIGNALS);
 461 }
 462
 463 /* It's a bit more tricky when 64-bit tasks are involved... */
 464 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 465 {
 466         unsigned long fp, distance, rval;
 467
 468         if (!(test_thread_flag(TIF_32BIT))) {
 469                 csp += STACK_BIAS;
 470                 psp += STACK_BIAS;
 471                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 472                 fp += STACK_BIAS;
 473         } else
 474                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 475
 476         /* Now 8-byte align the stack as this is mandatory in the
 477          * Sparc ABI due to how register windows work.  This hides
 478          * the restriction from thread libraries etc.  -DaveM
 479          */
 480         csp &= ~7UL;
 481
 482         distance = fp - psp;
 483         rval = (csp - distance);
 484         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
 485                 rval = 0;
 486         else if (test_thread_flag(TIF_32BIT)) {
 487                 if (put_user(((u32)csp),
 488                              &(((struct reg_window32 __user *)rval)->ins[6])))
 489                         rval = 0;
 490         } else {
 491                 if (put_user(((u64)csp - STACK_BIAS),
 492                              &(((struct reg_window __user *)rval)->ins[6])))
 493                         rval = 0;
 494                 else
 495                         rval = rval - STACK_BIAS;
 496         }
 497
 498         return rval;
 499 }
 500
 501 /* Standard stuff. */
 502 static inline void shift_window_buffer(int first_win, int last_win,
 503                                        struct thread_info *t)
 504 {
 505         int i;
 506
 507         for (i = first_win; i < last_win; i++) {
 508                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
 509                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
 510                        sizeof(struct reg_window));
 511         }
 512 }
 513
 514 void synchronize_user_stack(void)
 515 {
 516         struct thread_info *t = current_thread_info();
 517         unsigned long window;
 518
 519         flush_user_windows();
 520         if ((window = get_thread_wsaved()) != 0) {
 521                 int winsize = sizeof(struct reg_window);
 522                 int bias = 0;
 523
 524                 if (test_thread_flag(TIF_32BIT))
 525                         winsize = sizeof(struct reg_window32);
 526                 else
 527                         bias = STACK_BIAS;
 528
 529                 window -= 1;
 530                 do {
 531                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 532                         struct reg_window *rwin = &t->reg_window[window];
 533
 534                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
 535                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
 536                                 set_thread_wsaved(get_thread_wsaved() - 1);
 537                         }
 538                 } while (window--);
 539         }
 540 }
 541
 542 void fault_in_user_windows(void)
 543 {
 544         struct thread_info *t = current_thread_info();
 545         unsigned long window;
 546         int winsize = sizeof(struct reg_window);
 547         int bias = 0;
 548
 549         if (test_thread_flag(TIF_32BIT))
 550                 winsize = sizeof(struct reg_window32);
 551         else
 552                 bias = STACK_BIAS;
 553
 554         flush_user_windows();
 555         window = get_thread_wsaved();
 556
 557         if (window != 0) {
 558                 window -= 1;
 559                 do {
 560                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 561                         struct reg_window *rwin = &t->reg_window[window];
 562
 563                         if (copy_to_user((char __user *)sp, rwin, winsize))
 564                                 goto barf;
 565                 } while (window--);
 566         }
 567         set_thread_wsaved(0);
 568         return;
 569
 570 barf:
 571         set_thread_wsaved(window + 1);
 572         do_exit(SIGILL);
 573 }
 574
 575 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 576                               unsigned long stack_start,
 577                               struct pt_regs *regs,
 578                               unsigned long stack_size)
 579 {
 580         int __user *parent_tid_ptr, *child_tid_ptr;
 581
 582 #ifdef CONFIG_COMPAT
 583         if (test_thread_flag(TIF_32BIT)) {
 584                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 585                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 586         } else
 587 #endif
 588         {
 589                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 590                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 591         }
 592
 593         return do_fork(clone_flags, stack_start,
 594                        regs, stack_size,
 595                        parent_tid_ptr, child_tid_ptr);
 596 }
 597
 598 /* Copy a Sparc thread.  The fork() return value conventions
 599  * under SunOS are nothing short of bletcherous:
 600  * Parent -->  %o0 == childs  pid, %o1 == 0
 601  * Child  -->  %o0 == parents pid, %o1 == 1
 602  */
 603 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 604                 unsigned long unused,
 605                 struct task_struct *p, struct pt_regs *regs)
 606 {
 607         struct thread_info *t = p->thread_info;
 608         char *child_trap_frame;
 609
 610 #ifdef CONFIG_DEBUG_SPINLOCK
 611         p->thread.smp_lock_count = 0;
 612         p->thread.smp_lock_pc = 0;
 613 #endif
 614
 615         /* Calculate offset to stack_frame & pt_regs */
 616         child_trap_frame = ((char *)t) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
 617         memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
 618
 619         t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
 620                 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
 621         t->new_child = 1;
 622         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 623         t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
 624         t->fpsaved[0] = 0;
 625
 626         if (regs->tstate & TSTATE_PRIV) {
 627                 /* Special case, if we are spawning a kernel thread from
 628                  * a userspace task (via KMOD, NFS, or similar) we must
 629                  * disable performance counters in the child because the
 630                  * address space and protection realm are changing.
 631                  */
 632                 if (t->flags & _TIF_PERFCTR) {
 633                         t->user_cntd0 = t->user_cntd1 = NULL;
 634                         t->pcr_reg = 0;
 635                         t->flags &= ~_TIF_PERFCTR;
 636                 }
 637                 t->kregs->u_regs[UREG_FP] = t->ksp;
 638                 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
 639                 flush_register_windows();
 640                 memcpy((void *)(t->ksp + STACK_BIAS),
 641                        (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
 642                        sizeof(struct sparc_stackf));
 643                 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
 644                 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
 645         } else {
 646                 if (t->flags & _TIF_32BIT) {
 647                         sp &= 0x00000000ffffffffUL;
 648                         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 649                 }
 650                 t->kregs->u_regs[UREG_FP] = sp;
 651                 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
 652                 if (sp != regs->u_regs[UREG_FP]) {
 653                         unsigned long csp;
 654
 655                         csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 656                         if (!csp)
 657                                 return -EFAULT;
 658                         t->kregs->u_regs[UREG_FP] = csp;
 659                 }
 660                 if (t->utraps)
 661                         t->utraps[0]++;
 662         }
 663
 664         /* Set the return value for the child. */
 665         t->kregs->u_regs[UREG_I0] = current->pid;
 666         t->kregs->u_regs[UREG_I1] = 1;
 667
 668         /* Set the second return value for the parent. */
 669         regs->u_regs[UREG_I1] = 0;
 670
 671         if (clone_flags & CLONE_SETTLS)
 672                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 673
 674         return 0;
 675 }
 676
 677 /*
 678  * This is the mechanism for creating a new kernel thread.
 679  *
 680  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 681  * who haven't done an "execve()") should use this: it will work within
 682  * a system call from a "real" process, but the process memory space will
 683  * not be free'd until both the parent and the child have exited.
 684  */
 685 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 686 {
 687         long retval;
 688
 689         /* If the parent runs before fn(arg) is called by the child,
 690          * the input registers of this function can be clobbered.
 691          * So we stash 'fn' and 'arg' into global registers which
 692          * will not be modified by the parent.
 693          */
 694         __asm__ __volatile__("mov %4, %%g2\n\t"    /* Save FN into global */
 695                              "mov %5, %%g3\n\t"    /* Save ARG into global */
 696                              "mov %1, %%g1\n\t"    /* Clone syscall nr. */
 697                              "mov %2, %%o0\n\t"    /* Clone flags. */
 698                              "mov 0, %%o1\n\t"     /* usp arg == 0 */
 699                              "t 0x6d\n\t"          /* Linux/Sparc clone(). */
 700                              "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
 701                              " mov %%o0, %0\n\t"
 702                              "jmpl %%g2, %%o7\n\t"   /* Call the function. */
 703                              " mov %%g3, %%o0\n\t"   /* Set arg in delay. */
 704                              "mov %3, %%g1\n\t"
 705                              "t 0x6d\n\t"          /* Linux/Sparc exit(). */
 706                              /* Notreached by child. */
 707                              "1:" :
 708                              "=r" (retval) :
 709                              "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
 710                              "i" (__NR_exit),  "r" (fn), "r" (arg) :
 711                              "g1", "g2", "g3", "o0", "o1", "memory", "cc");
 712         return retval;
 713 }
 714
 715 /*
 716  * fill in the user structure for a core dump..
 717  */
 718 void dump_thread(struct pt_regs * regs, struct user * dump)
 719 {
 720         /* Only should be used for SunOS and ancient a.out
 721          * SparcLinux binaries...  Not worth implementing.
 722          */
 723         memset(dump, 0, sizeof(struct user));
 724 }
 725
 726 typedef struct {
 727         union {
 728                 unsigned int    pr_regs[32];
 729                 unsigned long   pr_dregs[16];
 730         } pr_fr;
 731         unsigned int __unused;
 732         unsigned int    pr_fsr;
 733         unsigned char   pr_qcnt;
 734         unsigned char   pr_q_entrysize;
 735         unsigned char   pr_en;
 736         unsigned int    pr_q[64];
 737 } elf_fpregset_t32;
 738
 739 /*
 740  * fill in the fpu structure for a core dump.
 741  */
 742 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 743 {
 744         unsigned long *kfpregs = current_thread_info()->fpregs;
 745         unsigned long fprs = current_thread_info()->fpsaved[0];
 746
 747         if (test_thread_flag(TIF_32BIT)) {
 748                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 749
 750                 if (fprs & FPRS_DL)
 751                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 752                                sizeof(unsigned int) * 32);
 753                 else
 754                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 755                                sizeof(unsigned int) * 32);
 756                 fpregs32->pr_qcnt = 0;
 757                 fpregs32->pr_q_entrysize = 8;
 758                 memset(&fpregs32->pr_q[0], 0,
 759                        (sizeof(unsigned int) * 64));
 760                 if (fprs & FPRS_FEF) {
 761                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 762                         fpregs32->pr_en = 1;
 763                 } else {
 764                         fpregs32->pr_fsr = 0;
 765                         fpregs32->pr_en = 0;
 766                 }
 767         } else {
 768                 if(fprs & FPRS_DL)
 769                         memcpy(&fpregs->pr_regs[0], kfpregs,
 770                                sizeof(unsigned int) * 32);
 771                 else
 772                         memset(&fpregs->pr_regs[0], 0,
 773                                sizeof(unsigned int) * 32);
 774                 if(fprs & FPRS_DU)
 775                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 776                                sizeof(unsigned int) * 32);
 777                 else
 778                         memset(&fpregs->pr_regs[16], 0,
 779                                sizeof(unsigned int) * 32);
 780                 if(fprs & FPRS_FEF) {
 781                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 782                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 783                 } else {
 784                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 785                 }
 786                 fpregs->pr_fprs = fprs;
 787         }
 788         return 1;
 789 }
 790
 791 /*
 792  * sparc_execve() executes a new program after the asm stub has set
 793  * things up for us.  This should basically do what I want it to.
 794  */
 795 asmlinkage int sparc_execve(struct pt_regs *regs)
 796 {
 797         int error, base = 0;
 798         char *filename;
 799
 800         /* User register window flush is done by entry.S */
 801
 802         /* Check for indirect call. */
 803         if (regs->u_regs[UREG_G1] == 0)
 804                 base = 1;
 805
 806         filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
 807         error = PTR_ERR(filename);
 808         if (IS_ERR(filename))
 809                 goto out;
 810         error = do_execve(filename,
 811                           (char __user * __user *)
 812                           regs->u_regs[base + UREG_I1],
 813                           (char __user * __user *)
 814                           regs->u_regs[base + UREG_I2], regs);
 815         putname(filename);
 816         if (!error) {
 817                 fprs_write(0);
 818                 current_thread_info()->xfsr[0] = 0;
 819                 current_thread_info()->fpsaved[0] = 0;
 820                 regs->tstate &= ~TSTATE_PEF;
 821                 task_lock(current);
 822                 current->ptrace &= ~PT_DTRACE;
 823                 task_unlock(current);
 824         }
 825 out:
 826         return error;
 827 }
 828
 829 unsigned long get_wchan(struct task_struct *task)
 830 {
 831         unsigned long pc, fp, bias = 0;
 832         unsigned long thread_info_base;
 833         struct reg_window *rw;
 834         unsigned long ret = 0;
 835         int count = 0;
 836
 837         if (!task || task == current ||
 838             task->state == TASK_RUNNING)
 839                 goto out;
 840
 841         thread_info_base = (unsigned long) task->thread_info;
 842         bias = STACK_BIAS;
 843         fp = task->thread_info->ksp + bias;
 844
 845         do {
 846                 /* Bogus frame pointer? */
 847                 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
 848                     fp >= (thread_info_base + THREAD_SIZE))
 849                         break;
 850                 rw = (struct reg_window *) fp;
 851                 pc = rw->ins[7];
 852                 if (!in_sched_functions(pc)) {
 853                         ret = pc;
 854                         goto out;
 855                 }
 856                 fp = rw->ins[6] + bias;
 857         } while (++count < 16);
 858
 859 out:
 860         return ret;
 861 }