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