arch/sparc64/kernel/process.c

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