arch/sparc64/kernel/process.c

   1 /*  $Id: process.c,v 1.131 2002/02/09 19:49:30 davem Exp $
   2  *  arch/sparc64/kernel/process.c
   3  *
   4  *  Copyright (C) 1995, 1996 David S. Miller (davem@caip.rutgers.edu)
   5  *  Copyright (C) 1996       Eddie C. Dost   (ecd@skynet.be)
   6  *  Copyright (C) 1997, 1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
   7  */
   8
   9 /*
  10  * This file handles the architecture-dependent parts of process handling..
  11  */
  12
  13 #include <stdarg.h>
  14
  15 #include <linux/errno.h>
  16 #include <linux/module.h>
  17 #include <linux/sched.h>
  18 #include <linux/kernel.h>
  19 #include <linux/kallsyms.h>
  20 #include <linux/mm.h>
  21 #include <linux/fs.h>
  22 #include <linux/smp.h>
  23 #include <linux/stddef.h>
  24 #include <linux/ptrace.h>
  25 #include <linux/slab.h>
  26 #include <linux/user.h>
  27 #include <linux/a.out.h>
  28 #include <linux/reboot.h>
  29 #include <linux/delay.h>
  30 #include <linux/compat.h>
  31 #include <linux/tick.h>
  32 #include <linux/init.h>
  33 #include <linux/cpu.h>
  34
  35 #include <asm/oplib.h>
  36 #include <asm/uaccess.h>
  37 #include <asm/system.h>
  38 #include <asm/page.h>
  39 #include <asm/pgalloc.h>
  40 #include <asm/pgtable.h>
  41 #include <asm/processor.h>
  42 #include <asm/pstate.h>
  43 #include <asm/elf.h>
  44 #include <asm/fpumacro.h>
  45 #include <asm/head.h>
  46 #include <asm/cpudata.h>
  47 #include <asm/mmu_context.h>
  48 #include <asm/unistd.h>
  49 #include <asm/hypervisor.h>
  50 #include <asm/sstate.h>
  51
  52 /* #define VERBOSE_SHOWREGS */
  53
  54 static void sparc64_yield(int cpu)
  55 {
  56         if (tlb_type != hypervisor)
  57                 return;
  58
  59         clear_thread_flag(TIF_POLLING_NRFLAG);
  60         smp_mb__after_clear_bit();
  61
  62         while (!need_resched() && !cpu_is_offline(cpu)) {
  63                 unsigned long pstate;
  64
  65                 /* Disable interrupts. */
  66                 __asm__ __volatile__(
  67                         "rdpr %%pstate, %0\n\t"
  68                         "andn %0, %1, %0\n\t"
  69                         "wrpr %0, %%g0, %%pstate"
  70                         : "=&r" (pstate)
  71                         : "i" (PSTATE_IE));
  72
  73                 if (!need_resched() && !cpu_is_offline(cpu))
  74                         sun4v_cpu_yield();
  75
  76                 /* Re-enable interrupts. */
  77                 __asm__ __volatile__(
  78                         "rdpr %%pstate, %0\n\t"
  79                         "or %0, %1, %0\n\t"
  80                         "wrpr %0, %%g0, %%pstate"
  81                         : "=&r" (pstate)
  82                         : "i" (PSTATE_IE));
  83         }
  84
  85         set_thread_flag(TIF_POLLING_NRFLAG);
  86 }
  87
  88 /* The idle loop on sparc64. */
  89 void cpu_idle(void)
  90 {
  91         int cpu = smp_processor_id();
  92
  93         set_thread_flag(TIF_POLLING_NRFLAG);
  94
  95         while(1) {
  96                 tick_nohz_stop_sched_tick();
  97
  98                 while (!need_resched() && !cpu_is_offline(cpu))
  99                         sparc64_yield(cpu);
 100
 101                 tick_nohz_restart_sched_tick();
 102
 103                 preempt_enable_no_resched();
 104
 105 #ifdef CONFIG_HOTPLUG_CPU
 106                 if (cpu_is_offline(cpu))
 107                         cpu_play_dead();
 108 #endif
 109
 110                 schedule();
 111                 preempt_disable();
 112         }
 113 }
 114
 115 extern char reboot_command [];
 116
 117 extern void (*prom_palette)(int);
 118 extern void (*prom_keyboard)(void);
 119
 120 void machine_halt(void)
 121 {
 122         sstate_halt();
 123         if (prom_palette)
 124                 prom_palette (1);
 125         if (prom_keyboard)
 126                 prom_keyboard();
 127         prom_halt();
 128         panic("Halt failed!");
 129 }
 130
 131 void machine_alt_power_off(void)
 132 {
 133         sstate_poweroff();
 134         if (prom_palette)
 135                 prom_palette(1);
 136         if (prom_keyboard)
 137                 prom_keyboard();
 138         prom_halt_power_off();
 139         panic("Power-off failed!");
 140 }
 141
 142 void machine_restart(char * cmd)
 143 {
 144         char *p;
 145
 146         sstate_reboot();
 147         p = strchr (reboot_command, '\n');
 148         if (p) *p = 0;
 149         if (prom_palette)
 150                 prom_palette (1);
 151         if (prom_keyboard)
 152                 prom_keyboard();
 153         if (cmd)
 154                 prom_reboot(cmd);
 155         if (*reboot_command)
 156                 prom_reboot(reboot_command);
 157         prom_reboot("");
 158         panic("Reboot failed!");
 159 }
 160
 161 #ifdef CONFIG_COMPAT
 162 static void show_regwindow32(struct pt_regs *regs)
 163 {
 164         struct reg_window32 __user *rw;
 165         struct reg_window32 r_w;
 166         mm_segment_t old_fs;
 167
 168         __asm__ __volatile__ ("flushw");
 169         rw = compat_ptr((unsigned)regs->u_regs[14]);
 170         old_fs = get_fs();
 171         set_fs (USER_DS);
 172         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 173                 set_fs (old_fs);
 174                 return;
 175         }
 176
 177         set_fs (old_fs);
 178         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
 179                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
 180                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
 181                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
 182         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
 183                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
 184                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
 185                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
 186 }
 187 #else
 188 #define show_regwindow32(regs)  do { } while (0)
 189 #endif
 190
 191 static void show_regwindow(struct pt_regs *regs)
 192 {
 193         struct reg_window __user *rw;
 194         struct reg_window *rwk;
 195         struct reg_window r_w;
 196         mm_segment_t old_fs;
 197
 198         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 199                 __asm__ __volatile__ ("flushw");
 200                 rw = (struct reg_window __user *)
 201                         (regs->u_regs[14] + STACK_BIAS);
 202                 rwk = (struct reg_window *)
 203                         (regs->u_regs[14] + STACK_BIAS);
 204                 if (!(regs->tstate & TSTATE_PRIV)) {
 205                         old_fs = get_fs();
 206                         set_fs (USER_DS);
 207                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 208                                 set_fs (old_fs);
 209                                 return;
 210                         }
 211                         rwk = &r_w;
 212                         set_fs (old_fs);
 213                 }
 214         } else {
 215                 show_regwindow32(regs);
 216                 return;
 217         }
 218         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 219                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 220         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 221                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 222         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 223                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 224         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 225                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 226         if (regs->tstate & TSTATE_PRIV)
 227                 print_symbol("I7: <%s>\n", rwk->ins[7]);
 228 }
 229
 230 void show_stackframe(struct sparc_stackf *sf)
 231 {
 232         unsigned long size;
 233         unsigned long *stk;
 234         int i;
 235
 236         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n"
 237                "l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 238                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
 239                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 240         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n"
 241                "i4: %016lx i5: %016lx fp: %016lx ret_pc: %016lx\n",
 242                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
 243                sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
 244         printk("sp: %016lx x0: %016lx x1: %016lx x2: %016lx\n"
 245                "x3: %016lx x4: %016lx x5: %016lx xx: %016lx\n",
 246                (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
 247                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 248                sf->xxargs[0]);
 249         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 250         size -= STACKFRAME_SZ;
 251         stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
 252         i = 0;
 253         do {
 254                 printk("s%d: %016lx\n", i++, *stk++);
 255         } while ((size -= sizeof(unsigned long)));
 256 }
 257
 258 void show_stackframe32(struct sparc_stackf32 *sf)
 259 {
 260         unsigned long size;
 261         unsigned *stk;
 262         int i;
 263
 264         printk("l0: %08x l1: %08x l2: %08x l3: %08x\n",
 265                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3]);
 266         printk("l4: %08x l5: %08x l6: %08x l7: %08x\n",
 267                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 268         printk("i0: %08x i1: %08x i2: %08x i3: %08x\n",
 269                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3]);
 270         printk("i4: %08x i5: %08x fp: %08x ret_pc: %08x\n",
 271                sf->ins[4], sf->ins[5], sf->fp, sf->callers_pc);
 272         printk("sp: %08x x0: %08x x1: %08x x2: %08x\n"
 273                "x3: %08x x4: %08x x5: %08x xx: %08x\n",
 274                sf->structptr, sf->xargs[0], sf->xargs[1],
 275                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 276                sf->xxargs[0]);
 277         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 278         size -= STACKFRAME32_SZ;
 279         stk = (unsigned *)((unsigned long)sf + STACKFRAME32_SZ);
 280         i = 0;
 281         do {
 282                 printk("s%d: %08x\n", i++, *stk++);
 283         } while ((size -= sizeof(unsigned)));
 284 }
 285
 286 #ifdef CONFIG_SMP
 287 static DEFINE_SPINLOCK(regdump_lock);
 288 #endif
 289
 290 void __show_regs(struct pt_regs * regs)
 291 {
 292 #ifdef CONFIG_SMP
 293         unsigned long flags;
 294
 295         /* Protect against xcall ipis which might lead to livelock on the lock */
 296         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 297                              "wrpr      %0, %1, %%pstate"
 298                              : "=r" (flags)
 299                              : "i" (PSTATE_IE));
 300         spin_lock(&regdump_lock);
 301 #endif
 302         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 303                regs->tpc, regs->tnpc, regs->y, print_tainted());
 304         print_symbol("TPC: <%s>\n", regs->tpc);
 305         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 306                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 307                regs->u_regs[3]);
 308         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 309                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 310                regs->u_regs[7]);
 311         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 312                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 313                regs->u_regs[11]);
 314         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 315                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 316                regs->u_regs[15]);
 317         print_symbol("RPC: <%s>\n", regs->u_regs[15]);
 318         show_regwindow(regs);
 319 #ifdef CONFIG_SMP
 320         spin_unlock(&regdump_lock);
 321         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
 322                              : : "r" (flags));
 323 #endif
 324 }
 325
 326 #ifdef VERBOSE_SHOWREGS
 327 static void idump_from_user (unsigned int *pc)
 328 {
 329         int i;
 330         int code;
 331
 332         if((((unsigned long) pc) & 3))
 333                 return;
 334
 335         pc -= 3;
 336         for(i = -3; i < 6; i++) {
 337                 get_user(code, pc);
 338                 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
 339                 pc++;
 340         }
 341         printk("\n");
 342 }
 343 #endif
 344
 345 void show_regs(struct pt_regs *regs)
 346 {
 347 #ifdef VERBOSE_SHOWREGS
 348         extern long etrap, etraptl1;
 349 #endif
 350         __show_regs(regs);
 351 #if 0
 352 #ifdef CONFIG_SMP
 353         {
 354                 extern void smp_report_regs(void);
 355
 356                 smp_report_regs();
 357         }
 358 #endif
 359 #endif
 360
 361 #ifdef VERBOSE_SHOWREGS
 362         if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
 363             regs->u_regs[14] >= (long)current - PAGE_SIZE &&
 364             regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
 365                 printk ("*********parent**********\n");
 366                 __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
 367                 idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
 368                 printk ("*********endpar**********\n");
 369         }
 370 #endif
 371 }
 372
 373 void show_regs32(struct pt_regs32 *regs)
 374 {
 375         printk("PSR: %08x PC: %08x NPC: %08x Y: %08x    %s\n", regs->psr,
 376                regs->pc, regs->npc, regs->y, print_tainted());
 377         printk("g0: %08x g1: %08x g2: %08x g3: %08x ",
 378                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 379                regs->u_regs[3]);
 380         printk("g4: %08x g5: %08x g6: %08x g7: %08x\n",
 381                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 382                regs->u_regs[7]);
 383         printk("o0: %08x o1: %08x o2: %08x o3: %08x ",
 384                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 385                regs->u_regs[11]);
 386         printk("o4: %08x o5: %08x sp: %08x ret_pc: %08x\n",
 387                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 388                regs->u_regs[15]);
 389 }
 390
 391 unsigned long thread_saved_pc(struct task_struct *tsk)
 392 {
 393         struct thread_info *ti = task_thread_info(tsk);
 394         unsigned long ret = 0xdeadbeefUL;
 395
 396         if (ti && ti->ksp) {
 397                 unsigned long *sp;
 398                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
 399                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
 400                     sp[14]) {
 401                         unsigned long *fp;
 402                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
 403                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
 404                                 ret = fp[15];
 405                 }
 406         }
 407         return ret;
 408 }
 409
 410 /* Free current thread data structures etc.. */
 411 void exit_thread(void)
 412 {
 413         struct thread_info *t = current_thread_info();
 414
 415         if (t->utraps) {
 416                 if (t->utraps[0] < 2)
 417                         kfree (t->utraps);
 418                 else
 419                         t->utraps[0]--;
 420         }
 421
 422         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 423                 t->user_cntd0 = t->user_cntd1 = NULL;
 424                 t->pcr_reg = 0;
 425                 write_pcr(0);
 426         }
 427 }
 428
 429 void flush_thread(void)
 430 {
 431         struct thread_info *t = current_thread_info();
 432         struct mm_struct *mm;
 433
 434         if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
 435                 clear_ti_thread_flag(t, TIF_ABI_PENDING);
 436                 if (test_ti_thread_flag(t, TIF_32BIT))
 437                         clear_ti_thread_flag(t, TIF_32BIT);
 438                 else
 439                         set_ti_thread_flag(t, TIF_32BIT);
 440         }
 441
 442         mm = t->task->mm;
 443         if (mm)
 444                 tsb_context_switch(mm);
 445
 446         set_thread_wsaved(0);
 447
 448         /* Turn off performance counters if on. */
 449         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 450                 t->user_cntd0 = t->user_cntd1 = NULL;
 451                 t->pcr_reg = 0;
 452                 write_pcr(0);
 453         }
 454
 455         /* Clear FPU register state. */
 456         t->fpsaved[0] = 0;
 457
 458         if (get_thread_current_ds() != ASI_AIUS)
 459                 set_fs(USER_DS);
 460
 461         /* Init new signal delivery disposition. */
 462         clear_thread_flag(TIF_NEWSIGNALS);
 463 }
 464
 465 /* It's a bit more tricky when 64-bit tasks are involved... */
 466 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 467 {
 468         unsigned long fp, distance, rval;
 469
 470         if (!(test_thread_flag(TIF_32BIT))) {
 471                 csp += STACK_BIAS;
 472                 psp += STACK_BIAS;
 473                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 474                 fp += STACK_BIAS;
 475         } else
 476                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 477
 478         /* Now 8-byte align the stack as this is mandatory in the
 479          * Sparc ABI due to how register windows work.  This hides
 480          * the restriction from thread libraries etc.  -DaveM
 481          */
 482         csp &= ~7UL;
 483
 484         distance = fp - psp;
 485         rval = (csp - distance);
 486         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
 487                 rval = 0;
 488         else if (test_thread_flag(TIF_32BIT)) {
 489                 if (put_user(((u32)csp),
 490                              &(((struct reg_window32 __user *)rval)->ins[6])))
 491                         rval = 0;
 492         } else {
 493                 if (put_user(((u64)csp - STACK_BIAS),
 494                              &(((struct reg_window __user *)rval)->ins[6])))
 495                         rval = 0;
 496                 else
 497                         rval = rval - STACK_BIAS;
 498         }
 499
 500         return rval;
 501 }
 502
 503 /* Standard stuff. */
 504 static inline void shift_window_buffer(int first_win, int last_win,
 505                                        struct thread_info *t)
 506 {
 507         int i;
 508
 509         for (i = first_win; i < last_win; i++) {
 510                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
 511                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
 512                        sizeof(struct reg_window));
 513         }
 514 }
 515
 516 void synchronize_user_stack(void)
 517 {
 518         struct thread_info *t = current_thread_info();
 519         unsigned long window;
 520
 521         flush_user_windows();
 522         if ((window = get_thread_wsaved()) != 0) {
 523                 int winsize = sizeof(struct reg_window);
 524                 int bias = 0;
 525
 526                 if (test_thread_flag(TIF_32BIT))
 527                         winsize = sizeof(struct reg_window32);
 528                 else
 529                         bias = STACK_BIAS;
 530
 531                 window -= 1;
 532                 do {
 533                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 534                         struct reg_window *rwin = &t->reg_window[window];
 535
 536                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
 537                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
 538                                 set_thread_wsaved(get_thread_wsaved() - 1);
 539                         }
 540                 } while (window--);
 541         }
 542 }
 543
 544 static void stack_unaligned(unsigned long sp)
 545 {
 546         siginfo_t info;
 547
 548         info.si_signo = SIGBUS;
 549         info.si_errno = 0;
 550         info.si_code = BUS_ADRALN;
 551         info.si_addr = (void __user *) sp;
 552         info.si_trapno = 0;
 553         force_sig_info(SIGBUS, &info, current);
 554 }
 555
 556 void fault_in_user_windows(void)
 557 {
 558         struct thread_info *t = current_thread_info();
 559         unsigned long window;
 560         int winsize = sizeof(struct reg_window);
 561         int bias = 0;
 562
 563         if (test_thread_flag(TIF_32BIT))
 564                 winsize = sizeof(struct reg_window32);
 565         else
 566                 bias = STACK_BIAS;
 567
 568         flush_user_windows();
 569         window = get_thread_wsaved();
 570
 571         if (likely(window != 0)) {
 572                 window -= 1;
 573                 do {
 574                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 575                         struct reg_window *rwin = &t->reg_window[window];
 576
 577                         if (unlikely(sp & 0x7UL))
 578                                 stack_unaligned(sp);
 579
 580                         if (unlikely(copy_to_user((char __user *)sp,
 581                                                   rwin, winsize)))
 582                                 goto barf;
 583                 } while (window--);
 584         }
 585         set_thread_wsaved(0);
 586         return;
 587
 588 barf:
 589         set_thread_wsaved(window + 1);
 590         do_exit(SIGILL);
 591 }
 592
 593 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 594                               unsigned long stack_start,
 595                               struct pt_regs *regs,
 596                               unsigned long stack_size)
 597 {
 598         int __user *parent_tid_ptr, *child_tid_ptr;
 599
 600 #ifdef CONFIG_COMPAT
 601         if (test_thread_flag(TIF_32BIT)) {
 602                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 603                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 604         } else
 605 #endif
 606         {
 607                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 608                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 609         }
 610
 611         return do_fork(clone_flags, stack_start,
 612                        regs, stack_size,
 613                        parent_tid_ptr, child_tid_ptr);
 614 }
 615
 616 /* Copy a Sparc thread.  The fork() return value conventions
 617  * under SunOS are nothing short of bletcherous:
 618  * Parent -->  %o0 == childs  pid, %o1 == 0
 619  * Child  -->  %o0 == parents pid, %o1 == 1
 620  */
 621 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 622                 unsigned long unused,
 623                 struct task_struct *p, struct pt_regs *regs)
 624 {
 625         struct thread_info *t = task_thread_info(p);
 626         char *child_trap_frame;
 627
 628         /* Calculate offset to stack_frame & pt_regs */
 629         child_trap_frame = task_stack_page(p) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
 630         memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
 631
 632         t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
 633                 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
 634         t->new_child = 1;
 635         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 636         t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
 637         t->fpsaved[0] = 0;
 638
 639         if (regs->tstate & TSTATE_PRIV) {
 640                 /* Special case, if we are spawning a kernel thread from
 641                  * a userspace task (via KMOD, NFS, or similar) we must
 642                  * disable performance counters in the child because the
 643                  * address space and protection realm are changing.
 644                  */
 645                 if (t->flags & _TIF_PERFCTR) {
 646                         t->user_cntd0 = t->user_cntd1 = NULL;
 647                         t->pcr_reg = 0;
 648                         t->flags &= ~_TIF_PERFCTR;
 649                 }
 650                 t->kregs->u_regs[UREG_FP] = t->ksp;
 651                 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
 652                 flush_register_windows();
 653                 memcpy((void *)(t->ksp + STACK_BIAS),
 654                        (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
 655                        sizeof(struct sparc_stackf));
 656                 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
 657                 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
 658         } else {
 659                 if (t->flags & _TIF_32BIT) {
 660                         sp &= 0x00000000ffffffffUL;
 661                         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 662                 }
 663                 t->kregs->u_regs[UREG_FP] = sp;
 664                 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
 665                 if (sp != regs->u_regs[UREG_FP]) {
 666                         unsigned long csp;
 667
 668                         csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 669                         if (!csp)
 670                                 return -EFAULT;
 671                         t->kregs->u_regs[UREG_FP] = csp;
 672                 }
 673                 if (t->utraps)
 674                         t->utraps[0]++;
 675         }
 676
 677         /* Set the return value for the child. */
 678         t->kregs->u_regs[UREG_I0] = current->pid;
 679         t->kregs->u_regs[UREG_I1] = 1;
 680
 681         /* Set the second return value for the parent. */
 682         regs->u_regs[UREG_I1] = 0;
 683
 684         if (clone_flags & CLONE_SETTLS)
 685                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 686
 687         return 0;
 688 }
 689
 690 /*
 691  * This is the mechanism for creating a new kernel thread.
 692  *
 693  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 694  * who haven't done an "execve()") should use this: it will work within
 695  * a system call from a "real" process, but the process memory space will
 696  * not be freed until both the parent and the child have exited.
 697  */
 698 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 699 {
 700         long retval;
 701
 702         /* If the parent runs before fn(arg) is called by the child,
 703          * the input registers of this function can be clobbered.
 704          * So we stash 'fn' and 'arg' into global registers which
 705          * will not be modified by the parent.
 706          */
 707         __asm__ __volatile__("mov %4, %%g2\n\t"    /* Save FN into global */
 708                              "mov %5, %%g3\n\t"    /* Save ARG into global */
 709                              "mov %1, %%g1\n\t"    /* Clone syscall nr. */
 710                              "mov %2, %%o0\n\t"    /* Clone flags. */
 711                              "mov 0, %%o1\n\t"     /* usp arg == 0 */
 712                              "t 0x6d\n\t"          /* Linux/Sparc clone(). */
 713                              "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
 714                              " mov %%o0, %0\n\t"
 715                              "jmpl %%g2, %%o7\n\t"   /* Call the function. */
 716                              " mov %%g3, %%o0\n\t"   /* Set arg in delay. */
 717                              "mov %3, %%g1\n\t"
 718                              "t 0x6d\n\t"          /* Linux/Sparc exit(). */
 719                              /* Notreached by child. */
 720                              "1:" :
 721                              "=r" (retval) :
 722                              "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
 723                              "i" (__NR_exit),  "r" (fn), "r" (arg) :
 724                              "g1", "g2", "g3", "o0", "o1", "memory", "cc");
 725         return retval;
 726 }
 727
 728 /*
 729  * fill in the user structure for a core dump..
 730  */
 731 void dump_thread(struct pt_regs * regs, struct user * dump)
 732 {
 733         /* Only should be used for SunOS and ancient a.out
 734          * SparcLinux binaries...  Not worth implementing.
 735          */
 736         memset(dump, 0, sizeof(struct user));
 737 }
 738
 739 typedef struct {
 740         union {
 741                 unsigned int    pr_regs[32];
 742                 unsigned long   pr_dregs[16];
 743         } pr_fr;
 744         unsigned int __unused;
 745         unsigned int    pr_fsr;
 746         unsigned char   pr_qcnt;
 747         unsigned char   pr_q_entrysize;
 748         unsigned char   pr_en;
 749         unsigned int    pr_q[64];
 750 } elf_fpregset_t32;
 751
 752 /*
 753  * fill in the fpu structure for a core dump.
 754  */
 755 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 756 {
 757         unsigned long *kfpregs = current_thread_info()->fpregs;
 758         unsigned long fprs = current_thread_info()->fpsaved[0];
 759
 760         if (test_thread_flag(TIF_32BIT)) {
 761                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 762
 763                 if (fprs & FPRS_DL)
 764                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 765                                sizeof(unsigned int) * 32);
 766                 else
 767                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 768                                sizeof(unsigned int) * 32);
 769                 fpregs32->pr_qcnt = 0;
 770                 fpregs32->pr_q_entrysize = 8;
 771                 memset(&fpregs32->pr_q[0], 0,
 772                        (sizeof(unsigned int) * 64));
 773                 if (fprs & FPRS_FEF) {
 774                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 775                         fpregs32->pr_en = 1;
 776                 } else {
 777                         fpregs32->pr_fsr = 0;
 778                         fpregs32->pr_en = 0;
 779                 }
 780         } else {
 781                 if(fprs & FPRS_DL)
 782                         memcpy(&fpregs->pr_regs[0], kfpregs,
 783                                sizeof(unsigned int) * 32);
 784                 else
 785                         memset(&fpregs->pr_regs[0], 0,
 786                                sizeof(unsigned int) * 32);
 787                 if(fprs & FPRS_DU)
 788                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 789                                sizeof(unsigned int) * 32);
 790                 else
 791                         memset(&fpregs->pr_regs[16], 0,
 792                                sizeof(unsigned int) * 32);
 793                 if(fprs & FPRS_FEF) {
 794                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 795                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 796                 } else {
 797                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 798                 }
 799                 fpregs->pr_fprs = fprs;
 800         }
 801         return 1;
 802 }
 803
 804 /*
 805  * sparc_execve() executes a new program after the asm stub has set
 806  * things up for us.  This should basically do what I want it to.
 807  */
 808 asmlinkage int sparc_execve(struct pt_regs *regs)
 809 {
 810         int error, base = 0;
 811         char *filename;
 812
 813         /* User register window flush is done by entry.S */
 814
 815         /* Check for indirect call. */
 816         if (regs->u_regs[UREG_G1] == 0)
 817                 base = 1;
 818
 819         filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
 820         error = PTR_ERR(filename);
 821         if (IS_ERR(filename))
 822                 goto out;
 823         error = do_execve(filename,
 824                           (char __user * __user *)
 825                           regs->u_regs[base + UREG_I1],
 826                           (char __user * __user *)
 827                           regs->u_regs[base + UREG_I2], regs);
 828         putname(filename);
 829         if (!error) {
 830                 fprs_write(0);
 831                 current_thread_info()->xfsr[0] = 0;
 832                 current_thread_info()->fpsaved[0] = 0;
 833                 regs->tstate &= ~TSTATE_PEF;
 834                 task_lock(current);
 835                 current->ptrace &= ~PT_DTRACE;
 836                 task_unlock(current);
 837         }
 838 out:
 839         return error;
 840 }
 841
 842 unsigned long get_wchan(struct task_struct *task)
 843 {
 844         unsigned long pc, fp, bias = 0;
 845         unsigned long thread_info_base;
 846         struct reg_window *rw;
 847         unsigned long ret = 0;
 848         int count = 0;
 849
 850         if (!task || task == current ||
 851             task->state == TASK_RUNNING)
 852                 goto out;
 853
 854         thread_info_base = (unsigned long) task_stack_page(task);
 855         bias = STACK_BIAS;
 856         fp = task_thread_info(task)->ksp + bias;
 857
 858         do {
 859                 /* Bogus frame pointer? */
 860                 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
 861                     fp >= (thread_info_base + THREAD_SIZE))
 862                         break;
 863                 rw = (struct reg_window *) fp;
 864                 pc = rw->ins[7];
 865                 if (!in_sched_functions(pc)) {
 866                         ret = pc;
 867                         goto out;
 868                 }
 869                 fp = rw->ins[6] + bias;
 870         } while (++count < 16);
 871
 872 out:
 873         return ret;
 874 }