arch/sparc64/kernel/process.c

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