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/config.h>
  16 #include <linux/errno.h>
  17 #include <linux/module.h>
  18 #include <linux/sched.h>
  19 #include <linux/kernel.h>
  20 #include <linux/kallsyms.h>
  21 #include <linux/mm.h>
  22 #include <linux/smp.h>
  23 #include <linux/smp_lock.h>
  24 #include <linux/stddef.h>
  25 #include <linux/ptrace.h>
  26 #include <linux/slab.h>
  27 #include <linux/user.h>
  28 #include <linux/a.out.h>
  29 #include <linux/config.h>
  30 #include <linux/reboot.h>
  31 #include <linux/delay.h>
  32 #include <linux/compat.h>
  33 #include <linux/init.h>
  34
  35 #include <asm/oplib.h>
  36 #include <asm/uaccess.h>
  37 #include <asm/system.h>
  38 #include <asm/page.h>
  39 #include <asm/pgalloc.h>
  40 #include <asm/pgtable.h>
  41 #include <asm/processor.h>
  42 #include <asm/pstate.h>
  43 #include <asm/elf.h>
  44 #include <asm/fpumacro.h>
  45 #include <asm/head.h>
  46 #include <asm/cpudata.h>
  47 #include <asm/unistd.h>
  48
  49 /* #define VERBOSE_SHOWREGS */
  50
  51 /*
  52  * Nothing special yet...
  53  */
  54 void default_idle(void)
  55 {
  56 }
  57
  58 #ifndef CONFIG_SMP
  59
  60 /*
  61  * the idle loop on a Sparc... ;)
  62  */
  63 void cpu_idle(void)
  64 {
  65         /* endless idle loop with no priority at all */
  66         for (;;) {
  67                 /* If current->work.need_resched is zero we should really
  68                  * setup for a system wakup event and execute a shutdown
  69                  * instruction.
  70                  *
  71                  * But this requires writing back the contents of the
  72                  * L2 cache etc. so implement this later. -DaveM
  73                  */
  74                 while (!need_resched())
  75                         barrier();
  76
  77                 preempt_enable_no_resched();
  78                 schedule();
  79                 preempt_disable();
  80                 check_pgt_cache();
  81         }
  82 }
  83
  84 #else
  85
  86 /*
  87  * the idle loop on a UltraMultiPenguin...
  88  *
  89  * TIF_POLLING_NRFLAG is set because we do not sleep the cpu
  90  * inside of the idler task, so an interrupt is not needed
  91  * to get a clean fast response.
  92  *
  93  * XXX Reverify this assumption... -DaveM
  94  *
  95  * Addendum: We do want it to do something for the signal
  96  *           delivery case, we detect that by just seeing
  97  *           if we are trying to send this to an idler or not.
  98  */
  99 void cpu_idle(void)
 100 {
 101         cpuinfo_sparc *cpuinfo = &local_cpu_data();
 102         set_thread_flag(TIF_POLLING_NRFLAG);
 103
 104         while(1) {
 105                 if (need_resched()) {
 106                         cpuinfo->idle_volume = 0;
 107                         preempt_enable_no_resched();
 108                         schedule();
 109                         preempt_disable();
 110                         check_pgt_cache();
 111                 }
 112                 cpuinfo->idle_volume++;
 113
 114                 /* The store ordering is so that IRQ handlers on
 115                  * other cpus see our increasing idleness for the buddy
 116                  * redistribution algorithm.  -DaveM
 117                  */
 118                 membar_storeload_storestore();
 119         }
 120 }
 121
 122 #endif
 123
 124 extern char reboot_command [];
 125
 126 extern void (*prom_palette)(int);
 127 extern void (*prom_keyboard)(void);
 128
 129 void machine_halt(void)
 130 {
 131         if (!serial_console && prom_palette)
 132                 prom_palette (1);
 133         if (prom_keyboard)
 134                 prom_keyboard();
 135         prom_halt();
 136         panic("Halt failed!");
 137 }
 138
 139 void machine_alt_power_off(void)
 140 {
 141         if (!serial_console && prom_palette)
 142                 prom_palette(1);
 143         if (prom_keyboard)
 144                 prom_keyboard();
 145         prom_halt_power_off();
 146         panic("Power-off failed!");
 147 }
 148
 149 void machine_restart(char * cmd)
 150 {
 151         char *p;
 152
 153         p = strchr (reboot_command, '\n');
 154         if (p) *p = 0;
 155         if (!serial_console && prom_palette)
 156                 prom_palette (1);
 157         if (prom_keyboard)
 158                 prom_keyboard();
 159         if (cmd)
 160                 prom_reboot(cmd);
 161         if (*reboot_command)
 162                 prom_reboot(reboot_command);
 163         prom_reboot("");
 164         panic("Reboot failed!");
 165 }
 166
 167 #ifdef CONFIG_COMPAT
 168 static void show_regwindow32(struct pt_regs *regs)
 169 {
 170         struct reg_window32 __user *rw;
 171         struct reg_window32 r_w;
 172         mm_segment_t old_fs;
 173
 174         __asm__ __volatile__ ("flushw");
 175         rw = compat_ptr((unsigned)regs->u_regs[14]);
 176         old_fs = get_fs();
 177         set_fs (USER_DS);
 178         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 179                 set_fs (old_fs);
 180                 return;
 181         }
 182
 183         set_fs (old_fs);
 184         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
 185                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
 186                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
 187                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
 188         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
 189                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
 190                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
 191                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
 192 }
 193 #else
 194 #define show_regwindow32(regs)  do { } while (0)
 195 #endif
 196
 197 static void show_regwindow(struct pt_regs *regs)
 198 {
 199         struct reg_window __user *rw;
 200         struct reg_window *rwk;
 201         struct reg_window r_w;
 202         mm_segment_t old_fs;
 203
 204         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 205                 __asm__ __volatile__ ("flushw");
 206                 rw = (struct reg_window __user *)
 207                         (regs->u_regs[14] + STACK_BIAS);
 208                 rwk = (struct reg_window *)
 209                         (regs->u_regs[14] + STACK_BIAS);
 210                 if (!(regs->tstate & TSTATE_PRIV)) {
 211                         old_fs = get_fs();
 212                         set_fs (USER_DS);
 213                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 214                                 set_fs (old_fs);
 215                                 return;
 216                         }
 217                         rwk = &r_w;
 218                         set_fs (old_fs);
 219                 }
 220         } else {
 221                 show_regwindow32(regs);
 222                 return;
 223         }
 224         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 225                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 226         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 227                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 228         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 229                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 230         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 231                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 232         if (regs->tstate & TSTATE_PRIV)
 233                 print_symbol("I7: <%s>\n", rwk->ins[7]);
 234 }
 235
 236 void show_stackframe(struct sparc_stackf *sf)
 237 {
 238         unsigned long size;
 239         unsigned long *stk;
 240         int i;
 241
 242         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n"
 243                "l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 244                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
 245                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 246         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n"
 247                "i4: %016lx i5: %016lx fp: %016lx ret_pc: %016lx\n",
 248                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
 249                sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
 250         printk("sp: %016lx x0: %016lx x1: %016lx x2: %016lx\n"
 251                "x3: %016lx x4: %016lx x5: %016lx xx: %016lx\n",
 252                (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
 253                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 254                sf->xxargs[0]);
 255         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 256         size -= STACKFRAME_SZ;
 257         stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
 258         i = 0;
 259         do {
 260                 printk("s%d: %016lx\n", i++, *stk++);
 261         } while ((size -= sizeof(unsigned long)));
 262 }
 263
 264 void show_stackframe32(struct sparc_stackf32 *sf)
 265 {
 266         unsigned long size;
 267         unsigned *stk;
 268         int i;
 269
 270         printk("l0: %08x l1: %08x l2: %08x l3: %08x\n",
 271                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3]);
 272         printk("l4: %08x l5: %08x l6: %08x l7: %08x\n",
 273                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
 274         printk("i0: %08x i1: %08x i2: %08x i3: %08x\n",
 275                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3]);
 276         printk("i4: %08x i5: %08x fp: %08x ret_pc: %08x\n",
 277                sf->ins[4], sf->ins[5], sf->fp, sf->callers_pc);
 278         printk("sp: %08x x0: %08x x1: %08x x2: %08x\n"
 279                "x3: %08x x4: %08x x5: %08x xx: %08x\n",
 280                sf->structptr, sf->xargs[0], sf->xargs[1],
 281                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
 282                sf->xxargs[0]);
 283         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
 284         size -= STACKFRAME32_SZ;
 285         stk = (unsigned *)((unsigned long)sf + STACKFRAME32_SZ);
 286         i = 0;
 287         do {
 288                 printk("s%d: %08x\n", i++, *stk++);
 289         } while ((size -= sizeof(unsigned)));
 290 }
 291
 292 #ifdef CONFIG_SMP
 293 static DEFINE_SPINLOCK(regdump_lock);
 294 #endif
 295
 296 void __show_regs(struct pt_regs * regs)
 297 {
 298 #ifdef CONFIG_SMP
 299         unsigned long flags;
 300
 301         /* Protect against xcall ipis which might lead to livelock on the lock */
 302         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 303                              "wrpr      %0, %1, %%pstate"
 304                              : "=r" (flags)
 305                              : "i" (PSTATE_IE));
 306         spin_lock(&regdump_lock);
 307 #endif
 308         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 309                regs->tpc, regs->tnpc, regs->y, print_tainted());
 310         print_symbol("TPC: <%s>\n", regs->tpc);
 311         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 312                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 313                regs->u_regs[3]);
 314         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 315                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 316                regs->u_regs[7]);
 317         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 318                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 319                regs->u_regs[11]);
 320         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 321                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 322                regs->u_regs[15]);
 323         print_symbol("RPC: <%s>\n", regs->u_regs[15]);
 324         show_regwindow(regs);
 325 #ifdef CONFIG_SMP
 326         spin_unlock(&regdump_lock);
 327         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
 328                              : : "r" (flags));
 329 #endif
 330 }
 331
 332 #ifdef VERBOSE_SHOWREGS
 333 static void idump_from_user (unsigned int *pc)
 334 {
 335         int i;
 336         int code;
 337
 338         if((((unsigned long) pc) & 3))
 339                 return;
 340
 341         pc -= 3;
 342         for(i = -3; i < 6; i++) {
 343                 get_user(code, pc);
 344                 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
 345                 pc++;
 346         }
 347         printk("\n");
 348 }
 349 #endif
 350
 351 void show_regs(struct pt_regs *regs)
 352 {
 353 #ifdef VERBOSE_SHOWREGS
 354         extern long etrap, etraptl1;
 355 #endif
 356         __show_regs(regs);
 357 #ifdef CONFIG_SMP
 358         {
 359                 extern void smp_report_regs(void);
 360
 361                 smp_report_regs();
 362         }
 363 #endif
 364
 365 #ifdef VERBOSE_SHOWREGS
 366         if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
 367             regs->u_regs[14] >= (long)current - PAGE_SIZE &&
 368             regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
 369                 printk ("*********parent**********\n");
 370                 __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
 371                 idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
 372                 printk ("*********endpar**********\n");
 373         }
 374 #endif
 375 }
 376
 377 void show_regs32(struct pt_regs32 *regs)
 378 {
 379         printk("PSR: %08x PC: %08x NPC: %08x Y: %08x    %s\n", regs->psr,
 380                regs->pc, regs->npc, regs->y, print_tainted());
 381         printk("g0: %08x g1: %08x g2: %08x g3: %08x ",
 382                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 383                regs->u_regs[3]);
 384         printk("g4: %08x g5: %08x g6: %08x g7: %08x\n",
 385                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 386                regs->u_regs[7]);
 387         printk("o0: %08x o1: %08x o2: %08x o3: %08x ",
 388                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 389                regs->u_regs[11]);
 390         printk("o4: %08x o5: %08x sp: %08x ret_pc: %08x\n",
 391                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 392                regs->u_regs[15]);
 393 }
 394
 395 unsigned long thread_saved_pc(struct task_struct *tsk)
 396 {
 397         struct thread_info *ti = task_thread_info(tsk);
 398         unsigned long ret = 0xdeadbeefUL;
 399
 400         if (ti && ti->ksp) {
 401                 unsigned long *sp;
 402                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
 403                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
 404                     sp[14]) {
 405                         unsigned long *fp;
 406                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
 407                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
 408                                 ret = fp[15];
 409                 }
 410         }
 411         return ret;
 412 }
 413
 414 /* Free current thread data structures etc.. */
 415 void exit_thread(void)
 416 {
 417         struct thread_info *t = current_thread_info();
 418
 419         if (t->utraps) {
 420                 if (t->utraps[0] < 2)
 421                         kfree (t->utraps);
 422                 else
 423                         t->utraps[0]--;
 424         }
 425
 426         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 427                 t->user_cntd0 = t->user_cntd1 = NULL;
 428                 t->pcr_reg = 0;
 429                 write_pcr(0);
 430         }
 431 }
 432
 433 void flush_thread(void)
 434 {
 435         struct thread_info *t = current_thread_info();
 436
 437         if (t->flags & _TIF_ABI_PENDING)
 438                 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
 439
 440         if (t->task->mm) {
 441                 unsigned long pgd_cache = 0UL;
 442                 if (test_thread_flag(TIF_32BIT)) {
 443                         struct mm_struct *mm = t->task->mm;
 444                         pgd_t *pgd0 = &mm->pgd[0];
 445                         pud_t *pud0 = pud_offset(pgd0, 0);
 446
 447                         if (pud_none(*pud0)) {
 448                                 pmd_t *page = pmd_alloc_one(mm, 0);
 449                                 pud_set(pud0, page);
 450                         }
 451                         pgd_cache = get_pgd_cache(pgd0);
 452                 }
 453                 __asm__ __volatile__("stxa %0, [%1] %2\n\t"
 454                                      "membar #Sync"
 455                                      : /* no outputs */
 456                                      : "r" (pgd_cache),
 457                                      "r" (TSB_REG),
 458                                      "i" (ASI_DMMU));
 459         }
 460         set_thread_wsaved(0);
 461
 462         /* Turn off performance counters if on. */
 463         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
 464                 t->user_cntd0 = t->user_cntd1 = NULL;
 465                 t->pcr_reg = 0;
 466                 write_pcr(0);
 467         }
 468
 469         /* Clear FPU register state. */
 470         t->fpsaved[0] = 0;
 471
 472         if (get_thread_current_ds() != ASI_AIUS)
 473                 set_fs(USER_DS);
 474
 475         /* Init new signal delivery disposition. */
 476         clear_thread_flag(TIF_NEWSIGNALS);
 477 }
 478
 479 /* It's a bit more tricky when 64-bit tasks are involved... */
 480 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 481 {
 482         unsigned long fp, distance, rval;
 483
 484         if (!(test_thread_flag(TIF_32BIT))) {
 485                 csp += STACK_BIAS;
 486                 psp += STACK_BIAS;
 487                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 488                 fp += STACK_BIAS;
 489         } else
 490                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 491
 492         /* Now 8-byte align the stack as this is mandatory in the
 493          * Sparc ABI due to how register windows work.  This hides
 494          * the restriction from thread libraries etc.  -DaveM
 495          */
 496         csp &= ~7UL;
 497
 498         distance = fp - psp;
 499         rval = (csp - distance);
 500         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
 501                 rval = 0;
 502         else if (test_thread_flag(TIF_32BIT)) {
 503                 if (put_user(((u32)csp),
 504                              &(((struct reg_window32 __user *)rval)->ins[6])))
 505                         rval = 0;
 506         } else {
 507                 if (put_user(((u64)csp - STACK_BIAS),
 508                              &(((struct reg_window __user *)rval)->ins[6])))
 509                         rval = 0;
 510                 else
 511                         rval = rval - STACK_BIAS;
 512         }
 513
 514         return rval;
 515 }
 516
 517 /* Standard stuff. */
 518 static inline void shift_window_buffer(int first_win, int last_win,
 519                                        struct thread_info *t)
 520 {
 521         int i;
 522
 523         for (i = first_win; i < last_win; i++) {
 524                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
 525                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
 526                        sizeof(struct reg_window));
 527         }
 528 }
 529
 530 void synchronize_user_stack(void)
 531 {
 532         struct thread_info *t = current_thread_info();
 533         unsigned long window;
 534
 535         flush_user_windows();
 536         if ((window = get_thread_wsaved()) != 0) {
 537                 int winsize = sizeof(struct reg_window);
 538                 int bias = 0;
 539
 540                 if (test_thread_flag(TIF_32BIT))
 541                         winsize = sizeof(struct reg_window32);
 542                 else
 543                         bias = STACK_BIAS;
 544
 545                 window -= 1;
 546                 do {
 547                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 548                         struct reg_window *rwin = &t->reg_window[window];
 549
 550                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
 551                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
 552                                 set_thread_wsaved(get_thread_wsaved() - 1);
 553                         }
 554                 } while (window--);
 555         }
 556 }
 557
 558 void fault_in_user_windows(void)
 559 {
 560         struct thread_info *t = current_thread_info();
 561         unsigned long window;
 562         int winsize = sizeof(struct reg_window);
 563         int bias = 0;
 564
 565         if (test_thread_flag(TIF_32BIT))
 566                 winsize = sizeof(struct reg_window32);
 567         else
 568                 bias = STACK_BIAS;
 569
 570         flush_user_windows();
 571         window = get_thread_wsaved();
 572
 573         if (window != 0) {
 574                 window -= 1;
 575                 do {
 576                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
 577                         struct reg_window *rwin = &t->reg_window[window];
 578
 579                         if (copy_to_user((char __user *)sp, rwin, winsize))
 580                                 goto barf;
 581                 } while (window--);
 582         }
 583         set_thread_wsaved(0);
 584         return;
 585
 586 barf:
 587         set_thread_wsaved(window + 1);
 588         do_exit(SIGILL);
 589 }
 590
 591 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 592                               unsigned long stack_start,
 593                               struct pt_regs *regs,
 594                               unsigned long stack_size)
 595 {
 596         int __user *parent_tid_ptr, *child_tid_ptr;
 597
 598 #ifdef CONFIG_COMPAT
 599         if (test_thread_flag(TIF_32BIT)) {
 600                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 601                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 602         } else
 603 #endif
 604         {
 605                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 606                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 607         }
 608
 609         return do_fork(clone_flags, stack_start,
 610                        regs, stack_size,
 611                        parent_tid_ptr, child_tid_ptr);
 612 }
 613
 614 /* Copy a Sparc thread.  The fork() return value conventions
 615  * under SunOS are nothing short of bletcherous:
 616  * Parent -->  %o0 == childs  pid, %o1 == 0
 617  * Child  -->  %o0 == parents pid, %o1 == 1
 618  */
 619 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 620                 unsigned long unused,
 621                 struct task_struct *p, struct pt_regs *regs)
 622 {
 623         struct thread_info *t = task_thread_info(p);
 624         char *child_trap_frame;
 625
 626         /* Calculate offset to stack_frame & pt_regs */
 627         child_trap_frame = task_stack_page(p) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
 628         memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
 629
 630         t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
 631                 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
 632         t->new_child = 1;
 633         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 634         t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
 635         t->fpsaved[0] = 0;
 636
 637         if (regs->tstate & TSTATE_PRIV) {
 638                 /* Special case, if we are spawning a kernel thread from
 639                  * a userspace task (via KMOD, NFS, or similar) we must
 640                  * disable performance counters in the child because the
 641                  * address space and protection realm are changing.
 642                  */
 643                 if (t->flags & _TIF_PERFCTR) {
 644                         t->user_cntd0 = t->user_cntd1 = NULL;
 645                         t->pcr_reg = 0;
 646                         t->flags &= ~_TIF_PERFCTR;
 647                 }
 648                 t->kregs->u_regs[UREG_FP] = t->ksp;
 649                 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
 650                 flush_register_windows();
 651                 memcpy((void *)(t->ksp + STACK_BIAS),
 652                        (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
 653                        sizeof(struct sparc_stackf));
 654                 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
 655                 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
 656         } else {
 657                 if (t->flags & _TIF_32BIT) {
 658                         sp &= 0x00000000ffffffffUL;
 659                         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 660                 }
 661                 t->kregs->u_regs[UREG_FP] = sp;
 662                 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
 663                 if (sp != regs->u_regs[UREG_FP]) {
 664                         unsigned long csp;
 665
 666                         csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 667                         if (!csp)
 668                                 return -EFAULT;
 669                         t->kregs->u_regs[UREG_FP] = csp;
 670                 }
 671                 if (t->utraps)
 672                         t->utraps[0]++;
 673         }
 674
 675         /* Set the return value for the child. */
 676         t->kregs->u_regs[UREG_I0] = current->pid;
 677         t->kregs->u_regs[UREG_I1] = 1;
 678
 679         /* Set the second return value for the parent. */
 680         regs->u_regs[UREG_I1] = 0;
 681
 682         if (clone_flags & CLONE_SETTLS)
 683                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 684
 685         return 0;
 686 }
 687
 688 /*
 689  * This is the mechanism for creating a new kernel thread.
 690  *
 691  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 692  * who haven't done an "execve()") should use this: it will work within
 693  * a system call from a "real" process, but the process memory space will
 694  * not be free'd until both the parent and the child have exited.
 695  */
 696 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 697 {
 698         long retval;
 699
 700         /* If the parent runs before fn(arg) is called by the child,
 701          * the input registers of this function can be clobbered.
 702          * So we stash 'fn' and 'arg' into global registers which
 703          * will not be modified by the parent.
 704          */
 705         __asm__ __volatile__("mov %4, %%g2\n\t"    /* Save FN into global */
 706                              "mov %5, %%g3\n\t"    /* Save ARG into global */
 707                              "mov %1, %%g1\n\t"    /* Clone syscall nr. */
 708                              "mov %2, %%o0\n\t"    /* Clone flags. */
 709                              "mov 0, %%o1\n\t"     /* usp arg == 0 */
 710                              "t 0x6d\n\t"          /* Linux/Sparc clone(). */
 711                              "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
 712                              " mov %%o0, %0\n\t"
 713                              "jmpl %%g2, %%o7\n\t"   /* Call the function. */
 714                              " mov %%g3, %%o0\n\t"   /* Set arg in delay. */
 715                              "mov %3, %%g1\n\t"
 716                              "t 0x6d\n\t"          /* Linux/Sparc exit(). */
 717                              /* Notreached by child. */
 718                              "1:" :
 719                              "=r" (retval) :
 720                              "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
 721                              "i" (__NR_exit),  "r" (fn), "r" (arg) :
 722                              "g1", "g2", "g3", "o0", "o1", "memory", "cc");
 723         return retval;
 724 }
 725
 726 /*
 727  * fill in the user structure for a core dump..
 728  */
 729 void dump_thread(struct pt_regs * regs, struct user * dump)
 730 {
 731         /* Only should be used for SunOS and ancient a.out
 732          * SparcLinux binaries...  Not worth implementing.
 733          */
 734         memset(dump, 0, sizeof(struct user));
 735 }
 736
 737 typedef struct {
 738         union {
 739                 unsigned int    pr_regs[32];
 740                 unsigned long   pr_dregs[16];
 741         } pr_fr;
 742         unsigned int __unused;
 743         unsigned int    pr_fsr;
 744         unsigned char   pr_qcnt;
 745         unsigned char   pr_q_entrysize;
 746         unsigned char   pr_en;
 747         unsigned int    pr_q[64];
 748 } elf_fpregset_t32;
 749
 750 /*
 751  * fill in the fpu structure for a core dump.
 752  */
 753 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 754 {
 755         unsigned long *kfpregs = current_thread_info()->fpregs;
 756         unsigned long fprs = current_thread_info()->fpsaved[0];
 757
 758         if (test_thread_flag(TIF_32BIT)) {
 759                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 760
 761                 if (fprs & FPRS_DL)
 762                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 763                                sizeof(unsigned int) * 32);
 764                 else
 765                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 766                                sizeof(unsigned int) * 32);
 767                 fpregs32->pr_qcnt = 0;
 768                 fpregs32->pr_q_entrysize = 8;
 769                 memset(&fpregs32->pr_q[0], 0,
 770                        (sizeof(unsigned int) * 64));
 771                 if (fprs & FPRS_FEF) {
 772                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 773                         fpregs32->pr_en = 1;
 774                 } else {
 775                         fpregs32->pr_fsr = 0;
 776                         fpregs32->pr_en = 0;
 777                 }
 778         } else {
 779                 if(fprs & FPRS_DL)
 780                         memcpy(&fpregs->pr_regs[0], kfpregs,
 781                                sizeof(unsigned int) * 32);
 782                 else
 783                         memset(&fpregs->pr_regs[0], 0,
 784                                sizeof(unsigned int) * 32);
 785                 if(fprs & FPRS_DU)
 786                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 787                                sizeof(unsigned int) * 32);
 788                 else
 789                         memset(&fpregs->pr_regs[16], 0,
 790                                sizeof(unsigned int) * 32);
 791                 if(fprs & FPRS_FEF) {
 792                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 793                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 794                 } else {
 795                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 796                 }
 797                 fpregs->pr_fprs = fprs;
 798         }
 799         return 1;
 800 }
 801
 802 /*
 803  * sparc_execve() executes a new program after the asm stub has set
 804  * things up for us.  This should basically do what I want it to.
 805  */
 806 asmlinkage int sparc_execve(struct pt_regs *regs)
 807 {
 808         int error, base = 0;
 809         char *filename;
 810
 811         /* User register window flush is done by entry.S */
 812
 813         /* Check for indirect call. */
 814         if (regs->u_regs[UREG_G1] == 0)
 815                 base = 1;
 816
 817         filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
 818         error = PTR_ERR(filename);
 819         if (IS_ERR(filename))
 820                 goto out;
 821         error = do_execve(filename,
 822                           (char __user * __user *)
 823                           regs->u_regs[base + UREG_I1],
 824                           (char __user * __user *)
 825                           regs->u_regs[base + UREG_I2], regs);
 826         putname(filename);
 827         if (!error) {
 828                 fprs_write(0);
 829                 current_thread_info()->xfsr[0] = 0;
 830                 current_thread_info()->fpsaved[0] = 0;
 831                 regs->tstate &= ~TSTATE_PEF;
 832                 task_lock(current);
 833                 current->ptrace &= ~PT_DTRACE;
 834                 task_unlock(current);
 835         }
 836 out:
 837         return error;
 838 }
 839
 840 unsigned long get_wchan(struct task_struct *task)
 841 {
 842         unsigned long pc, fp, bias = 0;
 843         unsigned long thread_info_base;
 844         struct reg_window *rw;
 845         unsigned long ret = 0;
 846         int count = 0;
 847
 848         if (!task || task == current ||
 849             task->state == TASK_RUNNING)
 850                 goto out;
 851
 852         thread_info_base = (unsigned long) task_stack_page(task);
 853         bias = STACK_BIAS;
 854         fp = task_thread_info(task)->ksp + bias;
 855
 856         do {
 857                 /* Bogus frame pointer? */
 858                 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
 859                     fp >= (thread_info_base + THREAD_SIZE))
 860                         break;
 861                 rw = (struct reg_window *) fp;
 862                 pc = rw->ins[7];
 863                 if (!in_sched_functions(pc)) {
 864                         ret = pc;
 865                         goto out;
 866                 }
 867                 fp = rw->ins[6] + bias;
 868         } while (++count < 16);
 869
 870 out:
 871         return ret;
 872 }