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