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/config.h>
  29 #include <linux/reboot.h>
  30 #include <linux/delay.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/unistd.h>
  46
  47 /* #define VERBOSE_SHOWREGS */
  48
  49 /*
  50  * Nothing special yet...
  51  */
  52 void default_idle(void)
  53 {
  54 }
  55
  56 #ifndef CONFIG_SMP
  57
  58 /*
  59  * the idle loop on a Sparc... ;)
  60  */
  61 int cpu_idle(void)
  62 {
  63         if (current->pid != 0)
  64                 return -EPERM;
  65
  66         /* endless idle loop with no priority at all */
  67         for (;;) {
  68                 /* If current->work.need_resched is zero we should really
  69                  * setup for a system wakup event and execute a shutdown
  70                  * instruction.
  71                  *
  72                  * But this requires writing back the contents of the
  73                  * L2 cache etc. so implement this later. -DaveM
  74                  */
  75                 while (!need_resched())
  76                         barrier();
  77
  78                 schedule();
  79                 check_pgt_cache();
  80         }
  81         return 0;
  82 }
  83
  84 #else
  85
  86 /*
  87  * the idle loop on a UltraMultiPenguin...
  88  */
  89 #define idle_me_harder()        (cpu_data(smp_processor_id()).idle_volume += 1)
  90 #define unidle_me()             (cpu_data(smp_processor_id()).idle_volume = 0)
  91 int cpu_idle(void)
  92 {
  93         set_thread_flag(TIF_POLLING_NRFLAG);
  94         while(1) {
  95                 if (need_resched()) {
  96                         unidle_me();
  97                         clear_thread_flag(TIF_POLLING_NRFLAG);
  98                         schedule();
  99                         set_thread_flag(TIF_POLLING_NRFLAG);
 100                         check_pgt_cache();
 101                 }
 102                 idle_me_harder();
 103
 104                 /* The store ordering is so that IRQ handlers on
 105                  * other cpus see our increasing idleness for the buddy
 106                  * redistribution algorithm.  -DaveM
 107                  */
 108                 membar("#StoreStore | #StoreLoad");
 109         }
 110 }
 111
 112 #endif
 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         if (!serial_console && prom_palette)
 122                 prom_palette (1);
 123         if (prom_keyboard)
 124                 prom_keyboard();
 125         prom_halt();
 126         panic("Halt failed!");
 127 }
 128
 129 EXPORT_SYMBOL(machine_halt);
 130
 131 void machine_alt_power_off(void)
 132 {
 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         p = strchr (reboot_command, '\n');
 146         if (p) *p = 0;
 147         if (!serial_console && prom_palette)
 148                 prom_palette (1);
 149         if (prom_keyboard)
 150                 prom_keyboard();
 151         if (cmd)
 152                 prom_reboot(cmd);
 153         if (*reboot_command)
 154                 prom_reboot(reboot_command);
 155         prom_reboot("");
 156         panic("Reboot failed!");
 157 }
 158
 159 EXPORT_SYMBOL(machine_restart);
 160
 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 = (struct reg_window32 __user *)((long)(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
 187 static void show_regwindow(struct pt_regs *regs)
 188 {
 189         struct reg_window __user *rw;
 190         struct reg_window *rwk;
 191         struct reg_window r_w;
 192         mm_segment_t old_fs;
 193
 194         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 195                 __asm__ __volatile__ ("flushw");
 196                 rw = (struct reg_window __user *)
 197                         (regs->u_regs[14] + STACK_BIAS);
 198                 rwk = (struct reg_window *)
 199                         (regs->u_regs[14] + STACK_BIAS);
 200                 if (!(regs->tstate & TSTATE_PRIV)) {
 201                         old_fs = get_fs();
 202                         set_fs (USER_DS);
 203                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 204                                 set_fs (old_fs);
 205                                 return;
 206                         }
 207                         rwk = &r_w;
 208                         set_fs (old_fs);
 209                 }
 210         } else {
 211                 show_regwindow32(regs);
 212                 return;
 213         }
 214         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 215                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 216         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 217                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 218         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 219                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 220         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 221                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 222         if (regs->tstate & TSTATE_PRIV)
 223                 print_symbol("I7: <%s>\n", rwk->ins[7]);
 224 }
 225
 226 void show_stackframe(struct sparc_stackf *sf)
 227 {
 228         unsigned long size;
 229         unsigned long *stk;
 230         int i;
 231
 232         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n"
 233                "l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 234                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
 235                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 236         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n"
 237                "i4: %016lx i5: %016lx fp: %016lx ret_pc: %016lx\n",
 238                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
 239                sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
 240         printk("sp: %016lx x0: %016lx x1: %016lx x2: %016lx\n"
 241                "x3: %016lx x4: %016lx x5: %016lx xx: %016lx\n",
 242                (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
 243                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 244                sf->xxargs[0]);
 245         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 246         size -= STACKFRAME_SZ;
 247         stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
 248         i = 0;
 249         do {
 250                 printk("s%d: %016lx\n", i++, *stk++);
 251         } while ((size -= sizeof(unsigned long)));
 252 }
 253
 254 void show_stackframe32(struct sparc_stackf32 *sf)
 255 {
 256         unsigned long size;
 257         unsigned *stk;
 258         int i;
 259
 260         printk("l0: %08x l1: %08x l2: %08x l3: %08x\n",
 261                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3]);
 262         printk("l4: %08x l5: %08x l6: %08x l7: %08x\n",
 263                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 264         printk("i0: %08x i1: %08x i2: %08x i3: %08x\n",
 265                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3]);
 266         printk("i4: %08x i5: %08x fp: %08x ret_pc: %08x\n",
 267                sf->ins[4], sf->ins[5], sf->fp, sf->callers_pc);
 268         printk("sp: %08x x0: %08x x1: %08x x2: %08x\n"
 269                "x3: %08x x4: %08x x5: %08x xx: %08x\n",
 270                sf->structptr, sf->xargs[0], sf->xargs[1],
 271                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 272                sf->xxargs[0]);
 273         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 274         size -= STACKFRAME32_SZ;
 275         stk = (unsigned *)((unsigned long)sf + STACKFRAME32_SZ);
 276         i = 0;
 277         do {
 278                 printk("s%d: %08x\n", i++, *stk++);
 279         } while ((size -= sizeof(unsigned)));
 280 }
 281
 282 #ifdef CONFIG_SMP
 283 static spinlock_t regdump_lock = SPIN_LOCK_UNLOCKED;
 284 #endif
 285
 286 void __show_regs(struct pt_regs * regs)
 287 {
 288 #ifdef CONFIG_SMP
 289         unsigned long flags;
 290
 291         /* Protect against xcall ipis which might lead to livelock on the lock */
 292         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 293                              "wrpr      %0, %1, %%pstate"
 294                              : "=r" (flags)
 295                              : "i" (PSTATE_IE));
 296         spin_lock(&regdump_lock);
 297 #endif
 298         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 299                regs->tpc, regs->tnpc, regs->y, print_tainted());
 300         print_symbol("TPC: <%s>\n", regs->tpc);
 301         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 302                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 303                regs->u_regs[3]);
 304         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 305                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 306                regs->u_regs[7]);
 307         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 308                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 309                regs->u_regs[11]);
 310         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 311                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 312                regs->u_regs[15]);
 313         print_symbol("RPC: <%s>\n", regs->u_regs[15]);
 314         show_regwindow(regs);
 315 #ifdef CONFIG_SMP
 316         spin_unlock(&regdump_lock);
 317         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
 318                              : : "r" (flags));
 319 #endif
 320 }
 321
 322 #ifdef VERBOSE_SHOWREGS
 323 static void idump_from_user (unsigned int *pc)
 324 {
 325         int i;
 326         int code;
 327
 328         if((((unsigned long) pc) & 3))
 329                 return;
 330
 331         pc -= 3;
 332         for(i = -3; i < 6; i++) {
 333                 get_user(code, pc);
 334                 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
 335                 pc++;
 336         }
 337         printk("\n");
 338 }
 339 #endif
 340
 341 void show_regs(struct pt_regs *regs)
 342 {
 343 #ifdef VERBOSE_SHOWREGS
 344         extern long etrap, etraptl1;
 345 #endif
 346         __show_regs(regs);
 347 #ifdef CONFIG_SMP
 348         {
 349                 extern void smp_report_regs(void);
 350
 351                 smp_report_regs();
 352         }
 353 #endif
 354
 355 #ifdef VERBOSE_SHOWREGS
 356         if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
 357             regs->u_regs[14] >= (long)current - PAGE_SIZE &&
 358             regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
 359                 printk ("*********parent**********\n");
 360                 __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
 361                 idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
 362                 printk ("*********endpar**********\n");
 363         }
 364 #endif
 365 }
 366
 367 void show_regs32(struct pt_regs32 *regs)
 368 {
 369         printk("PSR: %08x PC: %08x NPC: %08x Y: %08x    %s\n", regs->psr,
 370                regs->pc, regs->npc, regs->y, print_tainted());
 371         printk("g0: %08x g1: %08x g2: %08x g3: %08x ",
 372                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 373                regs->u_regs[3]);
 374         printk("g4: %08x g5: %08x g6: %08x g7: %08x\n",
 375                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 376                regs->u_regs[7]);
 377         printk("o0: %08x o1: %08x o2: %08x o3: %08x ",
 378                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 379                regs->u_regs[11]);
 380         printk("o4: %08x o5: %08x sp: %08x ret_pc: %08x\n",
 381                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 382                regs->u_regs[15]);
 383 }
 384
 385 unsigned long thread_saved_pc(struct task_struct *tsk)
 386 {
 387         struct thread_info *ti = tsk->thread_info;
 388         unsigned long ret = 0xdeadbeefUL;
 389
 390         if (ti && ti->ksp) {
 391                 unsigned long *sp;
 392                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
 393                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
 394                     sp[14]) {
 395                         unsigned long *fp;
 396                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
 397                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
 398                                 ret = fp[15];
 399                 }
 400         }
 401         return ret;
 402 }
 403
 404 /* Free current thread data structures etc.. */
 405 void exit_thread(void)
 406 {
 407         struct thread_info *t = current_thread_info();
 408
 409         if (t->utraps) {
 410                 if (t->utraps[0] < 2)
 411                         kfree (t->utraps);
 412                 else
 413                         t->utraps[0]--;
 414         }
 415
 416         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 417                 t->user_cntd0 = t->user_cntd1 = NULL;
 418                 t->pcr_reg = 0;
 419                 write_pcr(0);
 420         }
 421 }
 422
 423 void flush_thread(void)
 424 {
 425         struct thread_info *t = current_thread_info();
 426
 427         if (t->flags & _TIF_ABI_PENDING)
 428                 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
 429
 430         if (t->task->mm) {
 431                 unsigned long pgd_cache = 0UL;
 432                 if (test_thread_flag(TIF_32BIT)) {
 433                         struct mm_struct *mm = t->task->mm;
 434                         pgd_t *pgd0 = &mm->pgd[0];
 435
 436                         if (pgd_none(*pgd0)) {
 437                                 pmd_t *page = pmd_alloc_one_fast(NULL, 0);
 438                                 if (!page)
 439                                         page = pmd_alloc_one(NULL, 0);
 440                                 pgd_set(pgd0, page);
 441                         }
 442                         pgd_cache = ((unsigned long) pgd_val(*pgd0)) << 11UL;
 443                 }
 444                 __asm__ __volatile__("stxa %0, [%1] %2\n\t"
 445                                      "membar #Sync"
 446                                      : /* no outputs */
 447                                      : "r" (pgd_cache),
 448                                      "r" (TSB_REG),
 449                                      "i" (ASI_DMMU));
 450         }
 451         set_thread_wsaved(0);
 452
 453         /* Turn off performance counters if on. */
 454         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 455                 t->user_cntd0 = t->user_cntd1 = NULL;
 456                 t->pcr_reg = 0;
 457                 write_pcr(0);
 458         }
 459
 460         /* Clear FPU register state. */
 461         t->fpsaved[0] = 0;
 462
 463         if (get_thread_current_ds() != ASI_AIUS)
 464                 set_fs(USER_DS);
 465
 466         /* Init new signal delivery disposition. */
 467         clear_thread_flag(TIF_NEWSIGNALS);
 468 }
 469
 470 /* It's a bit more tricky when 64-bit tasks are involved... */
 471 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 472 {
 473         unsigned long fp, distance, rval;
 474
 475         if (!(test_thread_flag(TIF_32BIT))) {
 476                 csp += STACK_BIAS;
 477                 psp += STACK_BIAS;
 478                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 479                 fp += STACK_BIAS;
 480         } else
 481                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 482
 483         /* Now 8-byte align the stack as this is mandatory in the
 484          * Sparc ABI due to how register windows work.  This hides
 485          * the restriction from thread libraries etc.  -DaveM
 486          */
 487         csp &= ~7UL;
 488
 489         distance = fp - psp;
 490         rval = (csp - distance);
 491         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
 492                 rval = 0;
 493         else if (test_thread_flag(TIF_32BIT)) {
 494                 if (put_user(((u32)csp),
 495                              &(((struct reg_window32 __user *)rval)->ins[6])))
 496                         rval = 0;
 497         } else {
 498                 if (put_user(((u64)csp - STACK_BIAS),
 499                              &(((struct reg_window __user *)rval)->ins[6])))
 500                         rval = 0;
 501                 else
 502                         rval = rval - STACK_BIAS;
 503         }
 504
 505         return rval;
 506 }
 507
 508 /* Standard stuff. */
 509 static inline void shift_window_buffer(int first_win, int last_win,
 510                                        struct thread_info *t)
 511 {
 512         int i;
 513
 514         for (i = first_win; i < last_win; i++) {
 515                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
 516                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
 517                        sizeof(struct reg_window));
 518         }
 519 }
 520
 521 void synchronize_user_stack(void)
 522 {
 523         struct thread_info *t = current_thread_info();
 524         unsigned long window;
 525
 526         flush_user_windows();
 527         if ((window = get_thread_wsaved()) != 0) {
 528                 int winsize = sizeof(struct reg_window);
 529                 int bias = 0;
 530
 531                 if (test_thread_flag(TIF_32BIT))
 532                         winsize = sizeof(struct reg_window32);
 533                 else
 534                         bias = STACK_BIAS;
 535
 536                 window -= 1;
 537                 do {
 538                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 539                         struct reg_window *rwin = &t->reg_window[window];
 540
 541                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
 542                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
 543                                 set_thread_wsaved(get_thread_wsaved() - 1);
 544                         }
 545                 } while (window--);
 546         }
 547 }
 548
 549 void fault_in_user_windows(void)
 550 {
 551         struct thread_info *t = current_thread_info();
 552         unsigned long window;
 553         int winsize = sizeof(struct reg_window);
 554         int bias = 0;
 555
 556         if (test_thread_flag(TIF_32BIT))
 557                 winsize = sizeof(struct reg_window32);
 558         else
 559                 bias = STACK_BIAS;
 560
 561         flush_user_windows();
 562         window = get_thread_wsaved();
 563
 564         if (window != 0) {
 565                 window -= 1;
 566                 do {
 567                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 568                         struct reg_window *rwin = &t->reg_window[window];
 569
 570                         if (copy_to_user((char __user *)sp, rwin, winsize))
 571                                 goto barf;
 572                 } while (window--);
 573         }
 574         set_thread_wsaved(0);
 575         return;
 576
 577 barf:
 578         set_thread_wsaved(window + 1);
 579         do_exit(SIGILL);
 580 }
 581
 582 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 583                               unsigned long stack_start,
 584                               struct pt_regs *regs,
 585                               unsigned long stack_size)
 586 {
 587         int __user *parent_tid_ptr, *child_tid_ptr;
 588
 589         clone_flags &= ~CLONE_IDLETASK;
 590
 591         if (test_thread_flag(TIF_32BIT)) {
 592                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 593                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 594         } else {
 595                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 596                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 597         }
 598
 599         return do_fork(clone_flags, stack_start,
 600                        regs, stack_size,
 601                        parent_tid_ptr, child_tid_ptr);
 602 }
 603
 604 /* Copy a Sparc thread.  The fork() return value conventions
 605  * under SunOS are nothing short of bletcherous:
 606  * Parent -->  %o0 == childs  pid, %o1 == 0
 607  * Child  -->  %o0 == parents pid, %o1 == 1
 608  */
 609 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 610                 unsigned long unused,
 611                 struct task_struct *p, struct pt_regs *regs)
 612 {
 613         struct thread_info *t = p->thread_info;
 614         char *child_trap_frame;
 615
 616 #ifdef CONFIG_DEBUG_SPINLOCK
 617         p->thread.smp_lock_count = 0;
 618         p->thread.smp_lock_pc = 0;
 619 #endif
 620
 621         p->set_child_tid = p->clear_child_tid = NULL;
 622
 623         /* Calculate offset to stack_frame & pt_regs */
 624         child_trap_frame = ((char *)t) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
 625         memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
 626
 627         t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
 628                 _TIF_NEWCHILD |
 629                 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
 630         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 631         t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
 632         t->fpsaved[0] = 0;
 633
 634         if (regs->tstate & TSTATE_PRIV) {
 635                 /* Special case, if we are spawning a kernel thread from
 636                  * a userspace task (via KMOD, NFS, or similar) we must
 637                  * disable performance counters in the child because the
 638                  * address space and protection realm are changing.
 639                  */
 640                 if (t->flags & _TIF_PERFCTR) {
 641                         t->user_cntd0 = t->user_cntd1 = NULL;
 642                         t->pcr_reg = 0;
 643                         t->flags &= ~_TIF_PERFCTR;
 644                 }
 645                 t->kregs->u_regs[UREG_FP] = t->ksp;
 646                 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
 647                 flush_register_windows();
 648                 memcpy((void *)(t->ksp + STACK_BIAS),
 649                        (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
 650                        sizeof(struct sparc_stackf));
 651                 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
 652                 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
 653         } else {
 654                 if (t->flags & _TIF_32BIT) {
 655                         sp &= 0x00000000ffffffffUL;
 656                         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 657                 }
 658                 t->kregs->u_regs[UREG_FP] = sp;
 659                 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
 660                 if (sp != regs->u_regs[UREG_FP]) {
 661                         unsigned long csp;
 662
 663                         csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 664                         if (!csp)
 665                                 return -EFAULT;
 666                         t->kregs->u_regs[UREG_FP] = csp;
 667                 }
 668                 if (t->utraps)
 669                         t->utraps[0]++;
 670         }
 671
 672         /* Set the return value for the child. */
 673         t->kregs->u_regs[UREG_I0] = current->pid;
 674         t->kregs->u_regs[UREG_I1] = 1;
 675
 676         /* Set the second return value for the parent. */
 677         regs->u_regs[UREG_I1] = 0;
 678
 679         if (clone_flags & CLONE_SETTLS)
 680                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 681
 682         return 0;
 683 }
 684
 685 /*
 686  * This is the mechanism for creating a new kernel thread.
 687  *
 688  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 689  * who haven't done an "execve()") should use this: it will work within
 690  * a system call from a "real" process, but the process memory space will
 691  * not be free'd until both the parent and the child have exited.
 692  */
 693 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 694 {
 695         long retval;
 696
 697         /* If the parent runs before fn(arg) is called by the child,
 698          * the input registers of this function can be clobbered.
 699          * So we stash 'fn' and 'arg' into global registers which
 700          * will not be modified by the parent.
 701          */
 702         __asm__ __volatile__("mov %4, %%g2\n\t"    /* Save FN into global */
 703                              "mov %5, %%g3\n\t"    /* Save ARG into global */
 704                              "mov %1, %%g1\n\t"    /* Clone syscall nr. */
 705                              "mov %2, %%o0\n\t"    /* Clone flags. */
 706                              "mov 0, %%o1\n\t"     /* usp arg == 0 */
 707                              "t 0x6d\n\t"          /* Linux/Sparc clone(). */
 708                              "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
 709                              " mov %%o0, %0\n\t"
 710                              "jmpl %%g2, %%o7\n\t"   /* Call the function. */
 711                              " mov %%g3, %%o0\n\t"   /* Set arg in delay. */
 712                              "mov %3, %%g1\n\t"
 713                              "t 0x6d\n\t"          /* Linux/Sparc exit(). */
 714                              /* Notreached by child. */
 715                              "1:" :
 716                              "=r" (retval) :
 717                              "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
 718                              "i" (__NR_exit),  "r" (fn), "r" (arg) :
 719                              "g1", "g2", "g3", "o0", "o1", "memory", "cc");
 720         return retval;
 721 }
 722
 723 /*
 724  * fill in the user structure for a core dump..
 725  */
 726 void dump_thread(struct pt_regs * regs, struct user * dump)
 727 {
 728         /* Only should be used for SunOS and ancient a.out
 729          * SparcLinux binaries...  Not worth implementing.
 730          */
 731         memset(dump, 0, sizeof(struct user));
 732 }
 733
 734 typedef struct {
 735         union {
 736                 unsigned int    pr_regs[32];
 737                 unsigned long   pr_dregs[16];
 738         } pr_fr;
 739         unsigned int __unused;
 740         unsigned int    pr_fsr;
 741         unsigned char   pr_qcnt;
 742         unsigned char   pr_q_entrysize;
 743         unsigned char   pr_en;
 744         unsigned int    pr_q[64];
 745 } elf_fpregset_t32;
 746
 747 /*
 748  * fill in the fpu structure for a core dump.
 749  */
 750 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 751 {
 752         unsigned long *kfpregs = current_thread_info()->fpregs;
 753         unsigned long fprs = current_thread_info()->fpsaved[0];
 754
 755         if (test_thread_flag(TIF_32BIT)) {
 756                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 757
 758                 if (fprs & FPRS_DL)
 759                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 760                                sizeof(unsigned int) * 32);
 761                 else
 762                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 763                                sizeof(unsigned int) * 32);
 764                 fpregs32->pr_qcnt = 0;
 765                 fpregs32->pr_q_entrysize = 8;
 766                 memset(&fpregs32->pr_q[0], 0,
 767                        (sizeof(unsigned int) * 64));
 768                 if (fprs & FPRS_FEF) {
 769                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 770                         fpregs32->pr_en = 1;
 771                 } else {
 772                         fpregs32->pr_fsr = 0;
 773                         fpregs32->pr_en = 0;
 774                 }
 775         } else {
 776                 if(fprs & FPRS_DL)
 777                         memcpy(&fpregs->pr_regs[0], kfpregs,
 778                                sizeof(unsigned int) * 32);
 779                 else
 780                         memset(&fpregs->pr_regs[0], 0,
 781                                sizeof(unsigned int) * 32);
 782                 if(fprs & FPRS_DU)
 783                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 784                                sizeof(unsigned int) * 32);
 785                 else
 786                         memset(&fpregs->pr_regs[16], 0,
 787                                sizeof(unsigned int) * 32);
 788                 if(fprs & FPRS_FEF) {
 789                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 790                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 791                 } else {
 792                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 793                 }
 794                 fpregs->pr_fprs = fprs;
 795         }
 796         return 1;
 797 }
 798
 799 /*
 800  * sparc_execve() executes a new program after the asm stub has set
 801  * things up for us.  This should basically do what I want it to.
 802  */
 803 asmlinkage int sparc_execve(struct pt_regs *regs)
 804 {
 805         int error, base = 0;
 806         char *filename;
 807
 808         /* User register window flush is done by entry.S */
 809
 810         /* Check for indirect call. */
 811         if (regs->u_regs[UREG_G1] == 0)
 812                 base = 1;
 813
 814         filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
 815         error = PTR_ERR(filename);
 816         if (IS_ERR(filename))
 817                 goto out;
 818         error = do_execve(filename,
 819                           (char __user * __user *)
 820                           regs->u_regs[base + UREG_I1],
 821                           (char __user * __user *)
 822                           regs->u_regs[base + UREG_I2], regs);
 823         putname(filename);
 824         if (!error) {
 825                 fprs_write(0);
 826                 current_thread_info()->xfsr[0] = 0;
 827                 current_thread_info()->fpsaved[0] = 0;
 828                 regs->tstate &= ~TSTATE_PEF;
 829                 current->ptrace &= ~PT_DTRACE;
 830         }
 831 out:
 832         return error;
 833 }
 834
 835 unsigned long get_wchan(struct task_struct *task)
 836 {
 837         unsigned long pc, fp, bias = 0;
 838         unsigned long thread_info_base;
 839         struct reg_window *rw;
 840         unsigned long ret = 0;
 841         int count = 0;
 842
 843         if (!task || task == current ||
 844             task->state == TASK_RUNNING)
 845                 goto out;
 846
 847         thread_info_base = (unsigned long) task->thread_info;
 848         bias = STACK_BIAS;
 849         fp = task->thread_info->ksp + bias;
 850
 851         do {
 852                 /* Bogus frame pointer? */
 853                 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
 854                     fp >= (thread_info_base + THREAD_SIZE))
 855                         break;
 856                 rw = (struct reg_window *) fp;
 857                 pc = rw->ins[7];
 858                 if (!in_sched_functions(pc)) {
 859                         ret = pc;
 860                         goto out;
 861                 }
 862                 fp = rw->ins[6] + bias;
 863         } while (++count < 16);
 864
 865 out:
 866         return ret;
 867 }