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 EXPORT_SYMBOL(machine_halt);
 128
 129 void machine_alt_power_off(void)
 130 {
 131         if (!serial_console && prom_palette)
 132                 prom_palette(1);
 133         if (prom_keyboard)
 134                 prom_keyboard();
 135         prom_halt_power_off();
 136         panic("Power-off failed!");
 137 }
 138
 139 void machine_restart(char * cmd)
 140 {
 141         char *p;
 142
 143         p = strchr (reboot_command, '\n');
 144         if (p) *p = 0;
 145         if (!serial_console && prom_palette)
 146                 prom_palette (1);
 147         if (prom_keyboard)
 148                 prom_keyboard();
 149         if (cmd)
 150                 prom_reboot(cmd);
 151         if (*reboot_command)
 152                 prom_reboot(reboot_command);
 153         prom_reboot("");
 154         panic("Reboot failed!");
 155 }
 156
 157 EXPORT_SYMBOL(machine_restart);
 158
 159 static void show_regwindow32(struct pt_regs *regs)
 160 {
 161         struct reg_window32 __user *rw;
 162         struct reg_window32 r_w;
 163         mm_segment_t old_fs;
 164
 165         __asm__ __volatile__ ("flushw");
 166         rw = compat_ptr((unsigned)regs->u_regs[14]);
 167         old_fs = get_fs();
 168         set_fs (USER_DS);
 169         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 170                 set_fs (old_fs);
 171                 return;
 172         }
 173
 174         set_fs (old_fs);
 175         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
 176                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
 177                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
 178                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
 179         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
 180                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
 181                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
 182                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
 183 }
 184
 185 static void show_regwindow(struct pt_regs *regs)
 186 {
 187         struct reg_window __user *rw;
 188         struct reg_window *rwk;
 189         struct reg_window r_w;
 190         mm_segment_t old_fs;
 191
 192         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 193                 __asm__ __volatile__ ("flushw");
 194                 rw = (struct reg_window __user *)
 195                         (regs->u_regs[14] + STACK_BIAS);
 196                 rwk = (struct reg_window *)
 197                         (regs->u_regs[14] + STACK_BIAS);
 198                 if (!(regs->tstate & TSTATE_PRIV)) {
 199                         old_fs = get_fs();
 200                         set_fs (USER_DS);
 201                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 202                                 set_fs (old_fs);
 203                                 return;
 204                         }
 205                         rwk = &r_w;
 206                         set_fs (old_fs);
 207                 }
 208         } else {
 209                 show_regwindow32(regs);
 210                 return;
 211         }
 212         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 213                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 214         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 215                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 216         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 217                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 218         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 219                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 220         if (regs->tstate & TSTATE_PRIV)
 221                 print_symbol("I7: <%s>\n", rwk->ins[7]);
 222 }
 223
 224 void show_stackframe(struct sparc_stackf *sf)
 225 {
 226         unsigned long size;
 227         unsigned long *stk;
 228         int i;
 229
 230         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n"
 231                "l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 232                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
 233                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 234         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n"
 235                "i4: %016lx i5: %016lx fp: %016lx ret_pc: %016lx\n",
 236                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
 237                sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
 238         printk("sp: %016lx x0: %016lx x1: %016lx x2: %016lx\n"
 239                "x3: %016lx x4: %016lx x5: %016lx xx: %016lx\n",
 240                (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
 241                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 242                sf->xxargs[0]);
 243         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 244         size -= STACKFRAME_SZ;
 245         stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
 246         i = 0;
 247         do {
 248                 printk("s%d: %016lx\n", i++, *stk++);
 249         } while ((size -= sizeof(unsigned long)));
 250 }
 251
 252 void show_stackframe32(struct sparc_stackf32 *sf)
 253 {
 254         unsigned long size;
 255         unsigned *stk;
 256         int i;
 257
 258         printk("l0: %08x l1: %08x l2: %08x l3: %08x\n",
 259                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3]);
 260         printk("l4: %08x l5: %08x l6: %08x l7: %08x\n",
 261                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 262         printk("i0: %08x i1: %08x i2: %08x i3: %08x\n",
 263                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3]);
 264         printk("i4: %08x i5: %08x fp: %08x ret_pc: %08x\n",
 265                sf->ins[4], sf->ins[5], sf->fp, sf->callers_pc);
 266         printk("sp: %08x x0: %08x x1: %08x x2: %08x\n"
 267                "x3: %08x x4: %08x x5: %08x xx: %08x\n",
 268                sf->structptr, sf->xargs[0], sf->xargs[1],
 269                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 270                sf->xxargs[0]);
 271         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 272         size -= STACKFRAME32_SZ;
 273         stk = (unsigned *)((unsigned long)sf + STACKFRAME32_SZ);
 274         i = 0;
 275         do {
 276                 printk("s%d: %08x\n", i++, *stk++);
 277         } while ((size -= sizeof(unsigned)));
 278 }
 279
 280 #ifdef CONFIG_SMP
 281 static DEFINE_SPINLOCK(regdump_lock);
 282 #endif
 283
 284 void __show_regs(struct pt_regs * regs)
 285 {
 286 #ifdef CONFIG_SMP
 287         unsigned long flags;
 288
 289         /* Protect against xcall ipis which might lead to livelock on the lock */
 290         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 291                              "wrpr      %0, %1, %%pstate"
 292                              : "=r" (flags)
 293                              : "i" (PSTATE_IE));
 294         spin_lock(&regdump_lock);
 295 #endif
 296         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 297                regs->tpc, regs->tnpc, regs->y, print_tainted());
 298         print_symbol("TPC: <%s>\n", regs->tpc);
 299         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 300                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 301                regs->u_regs[3]);
 302         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 303                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 304                regs->u_regs[7]);
 305         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 306                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 307                regs->u_regs[11]);
 308         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 309                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 310                regs->u_regs[15]);
 311         print_symbol("RPC: <%s>\n", regs->u_regs[15]);
 312         show_regwindow(regs);
 313 #ifdef CONFIG_SMP
 314         spin_unlock(&regdump_lock);
 315         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
 316                              : : "r" (flags));
 317 #endif
 318 }
 319
 320 #ifdef VERBOSE_SHOWREGS
 321 static void idump_from_user (unsigned int *pc)
 322 {
 323         int i;
 324         int code;
 325
 326         if((((unsigned long) pc) & 3))
 327                 return;
 328
 329         pc -= 3;
 330         for(i = -3; i < 6; i++) {
 331                 get_user(code, pc);
 332                 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
 333                 pc++;
 334         }
 335         printk("\n");
 336 }
 337 #endif
 338
 339 void show_regs(struct pt_regs *regs)
 340 {
 341 #ifdef VERBOSE_SHOWREGS
 342         extern long etrap, etraptl1;
 343 #endif
 344         __show_regs(regs);
 345 #ifdef CONFIG_SMP
 346         {
 347                 extern void smp_report_regs(void);
 348
 349                 smp_report_regs();
 350         }
 351 #endif
 352
 353 #ifdef VERBOSE_SHOWREGS
 354         if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
 355             regs->u_regs[14] >= (long)current - PAGE_SIZE &&
 356             regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
 357                 printk ("*********parent**********\n");
 358                 __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
 359                 idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
 360                 printk ("*********endpar**********\n");
 361         }
 362 #endif
 363 }
 364
 365 void show_regs32(struct pt_regs32 *regs)
 366 {
 367         printk("PSR: %08x PC: %08x NPC: %08x Y: %08x    %s\n", regs->psr,
 368                regs->pc, regs->npc, regs->y, print_tainted());
 369         printk("g0: %08x g1: %08x g2: %08x g3: %08x ",
 370                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 371                regs->u_regs[3]);
 372         printk("g4: %08x g5: %08x g6: %08x g7: %08x\n",
 373                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 374                regs->u_regs[7]);
 375         printk("o0: %08x o1: %08x o2: %08x o3: %08x ",
 376                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 377                regs->u_regs[11]);
 378         printk("o4: %08x o5: %08x sp: %08x ret_pc: %08x\n",
 379                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 380                regs->u_regs[15]);
 381 }
 382
 383 unsigned long thread_saved_pc(struct task_struct *tsk)
 384 {
 385         struct thread_info *ti = tsk->thread_info;
 386         unsigned long ret = 0xdeadbeefUL;
 387
 388         if (ti && ti->ksp) {
 389                 unsigned long *sp;
 390                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
 391                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
 392                     sp[14]) {
 393                         unsigned long *fp;
 394                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
 395                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
 396                                 ret = fp[15];
 397                 }
 398         }
 399         return ret;
 400 }
 401
 402 /* Free current thread data structures etc.. */
 403 void exit_thread(void)
 404 {
 405         struct thread_info *t = current_thread_info();
 406
 407         if (t->utraps) {
 408                 if (t->utraps[0] < 2)
 409                         kfree (t->utraps);
 410                 else
 411                         t->utraps[0]--;
 412         }
 413
 414         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 415                 t->user_cntd0 = t->user_cntd1 = NULL;
 416                 t->pcr_reg = 0;
 417                 write_pcr(0);
 418         }
 419 }
 420
 421 void flush_thread(void)
 422 {
 423         struct thread_info *t = current_thread_info();
 424
 425         if (t->flags & _TIF_ABI_PENDING)
 426                 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
 427
 428         if (t->task->mm) {
 429                 unsigned long pgd_cache = 0UL;
 430                 if (test_thread_flag(TIF_32BIT)) {
 431                         struct mm_struct *mm = t->task->mm;
 432                         pgd_t *pgd0 = &mm->pgd[0];
 433                         pud_t *pud0 = pud_offset(pgd0, 0);
 434
 435                         if (pud_none(*pud0)) {
 436                                 pmd_t *page = pmd_alloc_one(mm, 0);
 437                                 pud_set(pud0, page);
 438                         }
 439                         pgd_cache = get_pgd_cache(pgd0);
 440                 }
 441                 __asm__ __volatile__("stxa %0, [%1] %2\n\t"
 442                                      "membar #Sync"
 443                                      : /* no outputs */
 444                                      : "r" (pgd_cache),
 445                                      "r" (TSB_REG),
 446                                      "i" (ASI_DMMU));
 447         }
 448         set_thread_wsaved(0);
 449
 450         /* Turn off performance counters if on. */
 451         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 452                 t->user_cntd0 = t->user_cntd1 = NULL;
 453                 t->pcr_reg = 0;
 454                 write_pcr(0);
 455         }
 456
 457         /* Clear FPU register state. */
 458         t->fpsaved[0] = 0;
 459
 460         if (get_thread_current_ds() != ASI_AIUS)
 461                 set_fs(USER_DS);
 462
 463         /* Init new signal delivery disposition. */
 464         clear_thread_flag(TIF_NEWSIGNALS);
 465 }
 466
 467 /* It's a bit more tricky when 64-bit tasks are involved... */
 468 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 469 {
 470         unsigned long fp, distance, rval;
 471
 472         if (!(test_thread_flag(TIF_32BIT))) {
 473                 csp += STACK_BIAS;
 474                 psp += STACK_BIAS;
 475                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 476                 fp += STACK_BIAS;
 477         } else
 478                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 479
 480         /* Now 8-byte align the stack as this is mandatory in the
 481          * Sparc ABI due to how register windows work.  This hides
 482          * the restriction from thread libraries etc.  -DaveM
 483          */
 484         csp &= ~7UL;
 485
 486         distance = fp - psp;
 487         rval = (csp - distance);
 488         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
 489                 rval = 0;
 490         else if (test_thread_flag(TIF_32BIT)) {
 491                 if (put_user(((u32)csp),
 492                              &(((struct reg_window32 __user *)rval)->ins[6])))
 493                         rval = 0;
 494         } else {
 495                 if (put_user(((u64)csp - STACK_BIAS),
 496                              &(((struct reg_window __user *)rval)->ins[6])))
 497                         rval = 0;
 498                 else
 499                         rval = rval - STACK_BIAS;
 500         }
 501
 502         return rval;
 503 }
 504
 505 /* Standard stuff. */
 506 static inline void shift_window_buffer(int first_win, int last_win,
 507                                        struct thread_info *t)
 508 {
 509         int i;
 510
 511         for (i = first_win; i < last_win; i++) {
 512                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
 513                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
 514                        sizeof(struct reg_window));
 515         }
 516 }
 517
 518 void synchronize_user_stack(void)
 519 {
 520         struct thread_info *t = current_thread_info();
 521         unsigned long window;
 522
 523         flush_user_windows();
 524         if ((window = get_thread_wsaved()) != 0) {
 525                 int winsize = sizeof(struct reg_window);
 526                 int bias = 0;
 527
 528                 if (test_thread_flag(TIF_32BIT))
 529                         winsize = sizeof(struct reg_window32);
 530                 else
 531                         bias = STACK_BIAS;
 532
 533                 window -= 1;
 534                 do {
 535                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 536                         struct reg_window *rwin = &t->reg_window[window];
 537
 538                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
 539                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
 540                                 set_thread_wsaved(get_thread_wsaved() - 1);
 541                         }
 542                 } while (window--);
 543         }
 544 }
 545
 546 void fault_in_user_windows(void)
 547 {
 548         struct thread_info *t = current_thread_info();
 549         unsigned long window;
 550         int winsize = sizeof(struct reg_window);
 551         int bias = 0;
 552
 553         if (test_thread_flag(TIF_32BIT))
 554                 winsize = sizeof(struct reg_window32);
 555         else
 556                 bias = STACK_BIAS;
 557
 558         flush_user_windows();
 559         window = get_thread_wsaved();
 560
 561         if (window != 0) {
 562                 window -= 1;
 563                 do {
 564                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 565                         struct reg_window *rwin = &t->reg_window[window];
 566
 567                         if (copy_to_user((char __user *)sp, rwin, winsize))
 568                                 goto barf;
 569                 } while (window--);
 570         }
 571         set_thread_wsaved(0);
 572         return;
 573
 574 barf:
 575         set_thread_wsaved(window + 1);
 576         do_exit(SIGILL);
 577 }
 578
 579 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 580                               unsigned long stack_start,
 581                               struct pt_regs *regs,
 582                               unsigned long stack_size)
 583 {
 584         int __user *parent_tid_ptr, *child_tid_ptr;
 585
 586 #ifdef CONFIG_COMPAT
 587         if (test_thread_flag(TIF_32BIT)) {
 588                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 589                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 590         } else
 591 #endif
 592         {
 593                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 594                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 595         }
 596
 597         return do_fork(clone_flags, stack_start,
 598                        regs, stack_size,
 599                        parent_tid_ptr, child_tid_ptr);
 600 }
 601
 602 /* Copy a Sparc thread.  The fork() return value conventions
 603  * under SunOS are nothing short of bletcherous:
 604  * Parent -->  %o0 == childs  pid, %o1 == 0
 605  * Child  -->  %o0 == parents pid, %o1 == 1
 606  */
 607 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 608                 unsigned long unused,
 609                 struct task_struct *p, struct pt_regs *regs)
 610 {
 611         struct thread_info *t = p->thread_info;
 612         char *child_trap_frame;
 613
 614 #ifdef CONFIG_DEBUG_SPINLOCK
 615         p->thread.smp_lock_count = 0;
 616         p->thread.smp_lock_pc = 0;
 617 #endif
 618
 619         /* Calculate offset to stack_frame & pt_regs */
 620         child_trap_frame = ((char *)t) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
 621         memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
 622
 623         t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
 624                 _TIF_NEWCHILD |
 625                 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
 626         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 627         t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
 628         t->fpsaved[0] = 0;
 629
 630         if (regs->tstate & TSTATE_PRIV) {
 631                 /* Special case, if we are spawning a kernel thread from
 632                  * a userspace task (via KMOD, NFS, or similar) we must
 633                  * disable performance counters in the child because the
 634                  * address space and protection realm are changing.
 635                  */
 636                 if (t->flags & _TIF_PERFCTR) {
 637                         t->user_cntd0 = t->user_cntd1 = NULL;
 638                         t->pcr_reg = 0;
 639                         t->flags &= ~_TIF_PERFCTR;
 640                 }
 641                 t->kregs->u_regs[UREG_FP] = t->ksp;
 642                 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
 643                 flush_register_windows();
 644                 memcpy((void *)(t->ksp + STACK_BIAS),
 645                        (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
 646                        sizeof(struct sparc_stackf));
 647                 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
 648                 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
 649         } else {
 650                 if (t->flags & _TIF_32BIT) {
 651                         sp &= 0x00000000ffffffffUL;
 652                         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 653                 }
 654                 t->kregs->u_regs[UREG_FP] = sp;
 655                 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
 656                 if (sp != regs->u_regs[UREG_FP]) {
 657                         unsigned long csp;
 658
 659                         csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 660                         if (!csp)
 661                                 return -EFAULT;
 662                         t->kregs->u_regs[UREG_FP] = csp;
 663                 }
 664                 if (t->utraps)
 665                         t->utraps[0]++;
 666         }
 667
 668         /* Set the return value for the child. */
 669         t->kregs->u_regs[UREG_I0] = current->pid;
 670         t->kregs->u_regs[UREG_I1] = 1;
 671
 672         /* Set the second return value for the parent. */
 673         regs->u_regs[UREG_I1] = 0;
 674
 675         if (clone_flags & CLONE_SETTLS)
 676                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 677
 678         return 0;
 679 }
 680
 681 /*
 682  * This is the mechanism for creating a new kernel thread.
 683  *
 684  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 685  * who haven't done an "execve()") should use this: it will work within
 686  * a system call from a "real" process, but the process memory space will
 687  * not be free'd until both the parent and the child have exited.
 688  */
 689 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 690 {
 691         long retval;
 692
 693         /* If the parent runs before fn(arg) is called by the child,
 694          * the input registers of this function can be clobbered.
 695          * So we stash 'fn' and 'arg' into global registers which
 696          * will not be modified by the parent.
 697          */
 698         __asm__ __volatile__("mov %4, %%g2\n\t"    /* Save FN into global */
 699                              "mov %5, %%g3\n\t"    /* Save ARG into global */
 700                              "mov %1, %%g1\n\t"    /* Clone syscall nr. */
 701                              "mov %2, %%o0\n\t"    /* Clone flags. */
 702                              "mov 0, %%o1\n\t"     /* usp arg == 0 */
 703                              "t 0x6d\n\t"          /* Linux/Sparc clone(). */
 704                              "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
 705                              " mov %%o0, %0\n\t"
 706                              "jmpl %%g2, %%o7\n\t"   /* Call the function. */
 707                              " mov %%g3, %%o0\n\t"   /* Set arg in delay. */
 708                              "mov %3, %%g1\n\t"
 709                              "t 0x6d\n\t"          /* Linux/Sparc exit(). */
 710                              /* Notreached by child. */
 711                              "1:" :
 712                              "=r" (retval) :
 713                              "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
 714                              "i" (__NR_exit),  "r" (fn), "r" (arg) :
 715                              "g1", "g2", "g3", "o0", "o1", "memory", "cc");
 716         return retval;
 717 }
 718
 719 /*
 720  * fill in the user structure for a core dump..
 721  */
 722 void dump_thread(struct pt_regs * regs, struct user * dump)
 723 {
 724         /* Only should be used for SunOS and ancient a.out
 725          * SparcLinux binaries...  Not worth implementing.
 726          */
 727         memset(dump, 0, sizeof(struct user));
 728 }
 729
 730 typedef struct {
 731         union {
 732                 unsigned int    pr_regs[32];
 733                 unsigned long   pr_dregs[16];
 734         } pr_fr;
 735         unsigned int __unused;
 736         unsigned int    pr_fsr;
 737         unsigned char   pr_qcnt;
 738         unsigned char   pr_q_entrysize;
 739         unsigned char   pr_en;
 740         unsigned int    pr_q[64];
 741 } elf_fpregset_t32;
 742
 743 /*
 744  * fill in the fpu structure for a core dump.
 745  */
 746 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 747 {
 748         unsigned long *kfpregs = current_thread_info()->fpregs;
 749         unsigned long fprs = current_thread_info()->fpsaved[0];
 750
 751         if (test_thread_flag(TIF_32BIT)) {
 752                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 753
 754                 if (fprs & FPRS_DL)
 755                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 756                                sizeof(unsigned int) * 32);
 757                 else
 758                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 759                                sizeof(unsigned int) * 32);
 760                 fpregs32->pr_qcnt = 0;
 761                 fpregs32->pr_q_entrysize = 8;
 762                 memset(&fpregs32->pr_q[0], 0,
 763                        (sizeof(unsigned int) * 64));
 764                 if (fprs & FPRS_FEF) {
 765                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 766                         fpregs32->pr_en = 1;
 767                 } else {
 768                         fpregs32->pr_fsr = 0;
 769                         fpregs32->pr_en = 0;
 770                 }
 771         } else {
 772                 if(fprs & FPRS_DL)
 773                         memcpy(&fpregs->pr_regs[0], kfpregs,
 774                                sizeof(unsigned int) * 32);
 775                 else
 776                         memset(&fpregs->pr_regs[0], 0,
 777                                sizeof(unsigned int) * 32);
 778                 if(fprs & FPRS_DU)
 779                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 780                                sizeof(unsigned int) * 32);
 781                 else
 782                         memset(&fpregs->pr_regs[16], 0,
 783                                sizeof(unsigned int) * 32);
 784                 if(fprs & FPRS_FEF) {
 785                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 786                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 787                 } else {
 788                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 789                 }
 790                 fpregs->pr_fprs = fprs;
 791         }
 792         return 1;
 793 }
 794
 795 /*
 796  * sparc_execve() executes a new program after the asm stub has set
 797  * things up for us.  This should basically do what I want it to.
 798  */
 799 asmlinkage int sparc_execve(struct pt_regs *regs)
 800 {
 801         int error, base = 0;
 802         char *filename;
 803
 804         /* User register window flush is done by entry.S */
 805
 806         /* Check for indirect call. */
 807         if (regs->u_regs[UREG_G1] == 0)
 808                 base = 1;
 809
 810         filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
 811         error = PTR_ERR(filename);
 812         if (IS_ERR(filename))
 813                 goto out;
 814         error = do_execve(filename,
 815                           (char __user * __user *)
 816                           regs->u_regs[base + UREG_I1],
 817                           (char __user * __user *)
 818                           regs->u_regs[base + UREG_I2], regs);
 819         putname(filename);
 820         if (!error) {
 821                 fprs_write(0);
 822                 current_thread_info()->xfsr[0] = 0;
 823                 current_thread_info()->fpsaved[0] = 0;
 824                 regs->tstate &= ~TSTATE_PEF;
 825                 task_lock(current);
 826                 current->ptrace &= ~PT_DTRACE;
 827                 task_unlock(current);
 828         }
 829 out:
 830         return error;
 831 }
 832
 833 unsigned long get_wchan(struct task_struct *task)
 834 {
 835         unsigned long pc, fp, bias = 0;
 836         unsigned long thread_info_base;
 837         struct reg_window *rw;
 838         unsigned long ret = 0;
 839         int count = 0;
 840
 841         if (!task || task == current ||
 842             task->state == TASK_RUNNING)
 843                 goto out;
 844
 845         thread_info_base = (unsigned long) task->thread_info;
 846         bias = STACK_BIAS;
 847         fp = task->thread_info->ksp + bias;
 848
 849         do {
 850                 /* Bogus frame pointer? */
 851                 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
 852                     fp >= (thread_info_base + THREAD_SIZE))
 853                         break;
 854                 rw = (struct reg_window *) fp;
 855                 pc = rw->ins[7];
 856                 if (!in_sched_functions(pc)) {
 857                         ret = pc;
 858                         goto out;
 859                 }
 860                 fp = rw->ins[6] + bias;
 861         } while (++count < 16);
 862
 863 out:
 864         return ret;
 865 }