arch/sparc/kernel/process_64.c

   1 /*  arch/sparc64/kernel/process.c
   2  *
   3  *  Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net)
   4  *  Copyright (C) 1996       Eddie C. Dost   (ecd@skynet.be)
   5  *  Copyright (C) 1997, 1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
   6  */
   7
   8 /*
   9  * This file handles the architecture-dependent parts of process handling..
  10  */
  11
  12 #include <stdarg.h>
  13
  14 #include <linux/errno.h>
  15 #include <linux/export.h>
  16 #include <linux/sched.h>
  17 #include <linux/kernel.h>
  18 #include <linux/mm.h>
  19 #include <linux/fs.h>
  20 #include <linux/smp.h>
  21 #include <linux/stddef.h>
  22 #include <linux/ptrace.h>
  23 #include <linux/slab.h>
  24 #include <linux/user.h>
  25 #include <linux/delay.h>
  26 #include <linux/compat.h>
  27 #include <linux/tick.h>
  28 #include <linux/init.h>
  29 #include <linux/cpu.h>
  30 #include <linux/perf_event.h>
  31 #include <linux/elfcore.h>
  32 #include <linux/sysrq.h>
  33 #include <linux/nmi.h>
  34
  35 #include <asm/uaccess.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/mmu_context.h>
  46 #include <asm/unistd.h>
  47 #include <asm/hypervisor.h>
  48 #include <asm/syscalls.h>
  49 #include <asm/irq_regs.h>
  50 #include <asm/smp.h>
  51 #include <asm/pcr.h>
  52
  53 #include "kstack.h"
  54
  55 /* Idle loop support on sparc64. */
  56 void arch_cpu_idle(void)
  57 {
  58         if (tlb_type != hypervisor) {
  59                 touch_nmi_watchdog();
  60                 local_irq_enable();
  61         } else {
  62                 unsigned long pstate;
  63
  64                 local_irq_enable();
  65
  66                 /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
  67                  * the cpu sleep hypervisor call.
  68                  */
  69                 __asm__ __volatile__(
  70                         "rdpr %%pstate, %0\n\t"
  71                         "andn %0, %1, %0\n\t"
  72                         "wrpr %0, %%g0, %%pstate"
  73                         : "=&r" (pstate)
  74                         : "i" (PSTATE_IE));
  75
  76                 if (!need_resched() && !cpu_is_offline(smp_processor_id()))
  77                         sun4v_cpu_yield();
  78
  79                 /* Re-enable interrupts. */
  80                 __asm__ __volatile__(
  81                         "rdpr %%pstate, %0\n\t"
  82                         "or %0, %1, %0\n\t"
  83                         "wrpr %0, %%g0, %%pstate"
  84                         : "=&r" (pstate)
  85                         : "i" (PSTATE_IE));
  86         }
  87 }
  88
  89 #ifdef CONFIG_HOTPLUG_CPU
  90 void arch_cpu_idle_dead()
  91 {
  92         sched_preempt_enable_no_resched();
  93         cpu_play_dead();
  94 }
  95 #endif
  96
  97 #ifdef CONFIG_COMPAT
  98 static void show_regwindow32(struct pt_regs *regs)
  99 {
 100         struct reg_window32 __user *rw;
 101         struct reg_window32 r_w;
 102         mm_segment_t old_fs;
 103
 104         __asm__ __volatile__ ("flushw");
 105         rw = compat_ptr((unsigned)regs->u_regs[14]);
 106         old_fs = get_fs();
 107         set_fs (USER_DS);
 108         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 109                 set_fs (old_fs);
 110                 return;
 111         }
 112
 113         set_fs (old_fs);
 114         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
 115                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
 116                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
 117                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
 118         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
 119                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
 120                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
 121                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
 122 }
 123 #else
 124 #define show_regwindow32(regs)  do { } while (0)
 125 #endif
 126
 127 static void show_regwindow(struct pt_regs *regs)
 128 {
 129         struct reg_window __user *rw;
 130         struct reg_window *rwk;
 131         struct reg_window r_w;
 132         mm_segment_t old_fs;
 133
 134         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 135                 __asm__ __volatile__ ("flushw");
 136                 rw = (struct reg_window __user *)
 137                         (regs->u_regs[14] + STACK_BIAS);
 138                 rwk = (struct reg_window *)
 139                         (regs->u_regs[14] + STACK_BIAS);
 140                 if (!(regs->tstate & TSTATE_PRIV)) {
 141                         old_fs = get_fs();
 142                         set_fs (USER_DS);
 143                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 144                                 set_fs (old_fs);
 145                                 return;
 146                         }
 147                         rwk = &r_w;
 148                         set_fs (old_fs);
 149                 }
 150         } else {
 151                 show_regwindow32(regs);
 152                 return;
 153         }
 154         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 155                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 156         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 157                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 158         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 159                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 160         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 161                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 162         if (regs->tstate & TSTATE_PRIV)
 163                 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
 164 }
 165
 166 void show_regs(struct pt_regs *regs)
 167 {
 168         show_regs_print_info(KERN_DEFAULT);
 169
 170         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 171                regs->tpc, regs->tnpc, regs->y, print_tainted());
 172         printk("TPC: <%pS>\n", (void *) regs->tpc);
 173         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 174                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 175                regs->u_regs[3]);
 176         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 177                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 178                regs->u_regs[7]);
 179         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 180                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 181                regs->u_regs[11]);
 182         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 183                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 184                regs->u_regs[15]);
 185         printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
 186         show_regwindow(regs);
 187         show_stack(current, (unsigned long *) regs->u_regs[UREG_FP]);
 188 }
 189
 190 union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
 191 static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
 192
 193 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
 194                               int this_cpu)
 195 {
 196         struct global_reg_snapshot *rp;
 197
 198         flushw_all();
 199
 200         rp = &global_cpu_snapshot[this_cpu].reg;
 201
 202         rp->tstate = regs->tstate;
 203         rp->tpc = regs->tpc;
 204         rp->tnpc = regs->tnpc;
 205         rp->o7 = regs->u_regs[UREG_I7];
 206
 207         if (regs->tstate & TSTATE_PRIV) {
 208                 struct reg_window *rw;
 209
 210                 rw = (struct reg_window *)
 211                         (regs->u_regs[UREG_FP] + STACK_BIAS);
 212                 if (kstack_valid(tp, (unsigned long) rw)) {
 213                         rp->i7 = rw->ins[7];
 214                         rw = (struct reg_window *)
 215                                 (rw->ins[6] + STACK_BIAS);
 216                         if (kstack_valid(tp, (unsigned long) rw))
 217                                 rp->rpc = rw->ins[7];
 218                 }
 219         } else {
 220                 rp->i7 = 0;
 221                 rp->rpc = 0;
 222         }
 223         rp->thread = tp;
 224 }
 225
 226 /* In order to avoid hangs we do not try to synchronize with the
 227  * global register dump client cpus.  The last store they make is to
 228  * the thread pointer, so do a short poll waiting for that to become
 229  * non-NULL.
 230  */
 231 static void __global_reg_poll(struct global_reg_snapshot *gp)
 232 {
 233         int limit = 0;
 234
 235         while (!gp->thread && ++limit < 100) {
 236                 barrier();
 237                 udelay(1);
 238         }
 239 }
 240
 241 void arch_trigger_all_cpu_backtrace(void)
 242 {
 243         struct thread_info *tp = current_thread_info();
 244         struct pt_regs *regs = get_irq_regs();
 245         unsigned long flags;
 246         int this_cpu, cpu;
 247
 248         if (!regs)
 249                 regs = tp->kregs;
 250
 251         spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
 252
 253         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
 254
 255         this_cpu = raw_smp_processor_id();
 256
 257         __global_reg_self(tp, regs, this_cpu);
 258
 259         smp_fetch_global_regs();
 260
 261         for_each_online_cpu(cpu) {
 262                 struct global_reg_snapshot *gp = &global_cpu_snapshot[cpu].reg;
 263
 264                 __global_reg_poll(gp);
 265
 266                 tp = gp->thread;
 267                 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
 268                        (cpu == this_cpu ? '*' : ' '), cpu,
 269                        gp->tstate, gp->tpc, gp->tnpc,
 270                        ((tp && tp->task) ? tp->task->comm : "NULL"),
 271                        ((tp && tp->task) ? tp->task->pid : -1));
 272
 273                 if (gp->tstate & TSTATE_PRIV) {
 274                         printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
 275                                (void *) gp->tpc,
 276                                (void *) gp->o7,
 277                                (void *) gp->i7,
 278                                (void *) gp->rpc);
 279                 } else {
 280                         printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
 281                                gp->tpc, gp->o7, gp->i7, gp->rpc);
 282                 }
 283         }
 284
 285         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
 286
 287         spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
 288 }
 289
 290 #ifdef CONFIG_MAGIC_SYSRQ
 291
 292 static void sysrq_handle_globreg(int key)
 293 {
 294         arch_trigger_all_cpu_backtrace();
 295 }
 296
 297 static struct sysrq_key_op sparc_globalreg_op = {
 298         .handler        = sysrq_handle_globreg,
 299         .help_msg       = "global-regs(y)",
 300         .action_msg     = "Show Global CPU Regs",
 301 };
 302
 303 static void __global_pmu_self(int this_cpu)
 304 {
 305         struct global_pmu_snapshot *pp;
 306         int i, num;
 307
 308         pp = &global_cpu_snapshot[this_cpu].pmu;
 309
 310         num = 1;
 311         if (tlb_type == hypervisor &&
 312             sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
 313                 num = 4;
 314
 315         for (i = 0; i < num; i++) {
 316                 pp->pcr[i] = pcr_ops->read_pcr(i);
 317                 pp->pic[i] = pcr_ops->read_pic(i);
 318         }
 319 }
 320
 321 static void __global_pmu_poll(struct global_pmu_snapshot *pp)
 322 {
 323         int limit = 0;
 324
 325         while (!pp->pcr[0] && ++limit < 100) {
 326                 barrier();
 327                 udelay(1);
 328         }
 329 }
 330
 331 static void pmu_snapshot_all_cpus(void)
 332 {
 333         unsigned long flags;
 334         int this_cpu, cpu;
 335
 336         spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
 337
 338         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
 339
 340         this_cpu = raw_smp_processor_id();
 341
 342         __global_pmu_self(this_cpu);
 343
 344         smp_fetch_global_pmu();
 345
 346         for_each_online_cpu(cpu) {
 347                 struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
 348
 349                 __global_pmu_poll(pp);
 350
 351                 printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
 352                        (cpu == this_cpu ? '*' : ' '), cpu,
 353                        pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
 354                        pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
 355         }
 356
 357         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
 358
 359         spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
 360 }
 361
 362 static void sysrq_handle_globpmu(int key)
 363 {
 364         pmu_snapshot_all_cpus();
 365 }
 366
 367 static struct sysrq_key_op sparc_globalpmu_op = {
 368         .handler        = sysrq_handle_globpmu,
 369         .help_msg       = "global-pmu(x)",
 370         .action_msg     = "Show Global PMU Regs",
 371 };
 372
 373 static int __init sparc_sysrq_init(void)
 374 {
 375         int ret = register_sysrq_key('y', &sparc_globalreg_op);
 376
 377         if (!ret)
 378                 ret = register_sysrq_key('x', &sparc_globalpmu_op);
 379         return ret;
 380 }
 381
 382 core_initcall(sparc_sysrq_init);
 383
 384 #endif
 385
 386 unsigned long thread_saved_pc(struct task_struct *tsk)
 387 {
 388         struct thread_info *ti = task_thread_info(tsk);
 389         unsigned long ret = 0xdeadbeefUL;
 390
 391         if (ti && ti->ksp) {
 392                 unsigned long *sp;
 393                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
 394                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
 395                     sp[14]) {
 396                         unsigned long *fp;
 397                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
 398                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
 399                                 ret = fp[15];
 400                 }
 401         }
 402         return ret;
 403 }
 404
 405 /* Free current thread data structures etc.. */
 406 void exit_thread(void)
 407 {
 408         struct thread_info *t = current_thread_info();
 409
 410         if (t->utraps) {
 411                 if (t->utraps[0] < 2)
 412                         kfree (t->utraps);
 413                 else
 414                         t->utraps[0]--;
 415         }
 416 }
 417
 418 void flush_thread(void)
 419 {
 420         struct thread_info *t = current_thread_info();
 421         struct mm_struct *mm;
 422
 423         mm = t->task->mm;
 424         if (mm)
 425                 tsb_context_switch(mm);
 426
 427         set_thread_wsaved(0);
 428
 429         /* Clear FPU register state. */
 430         t->fpsaved[0] = 0;
 431 }
 432
 433 /* It's a bit more tricky when 64-bit tasks are involved... */
 434 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 435 {
 436         bool stack_64bit = test_thread_64bit_stack(psp);
 437         unsigned long fp, distance, rval;
 438
 439         if (stack_64bit) {
 440                 csp += STACK_BIAS;
 441                 psp += STACK_BIAS;
 442                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 443                 fp += STACK_BIAS;
 444                 if (test_thread_flag(TIF_32BIT))
 445                         fp &= 0xffffffff;
 446         } else
 447                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 448
 449         /* Now align the stack as this is mandatory in the Sparc ABI
 450          * due to how register windows work.  This hides the
 451          * restriction from thread libraries etc.
 452          */
 453         csp &= ~15UL;
 454
 455         distance = fp - psp;
 456         rval = (csp - distance);
 457         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
 458                 rval = 0;
 459         else if (!stack_64bit) {
 460                 if (put_user(((u32)csp),
 461                              &(((struct reg_window32 __user *)rval)->ins[6])))
 462                         rval = 0;
 463         } else {
 464                 if (put_user(((u64)csp - STACK_BIAS),
 465                              &(((struct reg_window __user *)rval)->ins[6])))
 466                         rval = 0;
 467                 else
 468                         rval = rval - STACK_BIAS;
 469         }
 470
 471         return rval;
 472 }
 473
 474 /* Standard stuff. */
 475 static inline void shift_window_buffer(int first_win, int last_win,
 476                                        struct thread_info *t)
 477 {
 478         int i;
 479
 480         for (i = first_win; i < last_win; i++) {
 481                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
 482                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
 483                        sizeof(struct reg_window));
 484         }
 485 }
 486
 487 void synchronize_user_stack(void)
 488 {
 489         struct thread_info *t = current_thread_info();
 490         unsigned long window;
 491
 492         flush_user_windows();
 493         if ((window = get_thread_wsaved()) != 0) {
 494                 window -= 1;
 495                 do {
 496                         struct reg_window *rwin = &t->reg_window[window];
 497                         int winsize = sizeof(struct reg_window);
 498                         unsigned long sp;
 499
 500                         sp = t->rwbuf_stkptrs[window];
 501
 502                         if (test_thread_64bit_stack(sp))
 503                                 sp += STACK_BIAS;
 504                         else
 505                                 winsize = sizeof(struct reg_window32);
 506
 507                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
 508                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
 509                                 set_thread_wsaved(get_thread_wsaved() - 1);
 510                         }
 511                 } while (window--);
 512         }
 513 }
 514
 515 static void stack_unaligned(unsigned long sp)
 516 {
 517         siginfo_t info;
 518
 519         info.si_signo = SIGBUS;
 520         info.si_errno = 0;
 521         info.si_code = BUS_ADRALN;
 522         info.si_addr = (void __user *) sp;
 523         info.si_trapno = 0;
 524         force_sig_info(SIGBUS, &info, current);
 525 }
 526
 527 void fault_in_user_windows(void)
 528 {
 529         struct thread_info *t = current_thread_info();
 530         unsigned long window;
 531
 532         flush_user_windows();
 533         window = get_thread_wsaved();
 534
 535         if (likely(window != 0)) {
 536                 window -= 1;
 537                 do {
 538                         struct reg_window *rwin = &t->reg_window[window];
 539                         int winsize = sizeof(struct reg_window);
 540                         unsigned long sp;
 541
 542                         sp = t->rwbuf_stkptrs[window];
 543
 544                         if (test_thread_64bit_stack(sp))
 545                                 sp += STACK_BIAS;
 546                         else
 547                                 winsize = sizeof(struct reg_window32);
 548
 549                         if (unlikely(sp & 0x7UL))
 550                                 stack_unaligned(sp);
 551
 552                         if (unlikely(copy_to_user((char __user *)sp,
 553                                                   rwin, winsize)))
 554                                 goto barf;
 555                 } while (window--);
 556         }
 557         set_thread_wsaved(0);
 558         return;
 559
 560 barf:
 561         set_thread_wsaved(window + 1);
 562         do_exit(SIGILL);
 563 }
 564
 565 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 566                               unsigned long stack_start,
 567                               struct pt_regs *regs,
 568                               unsigned long stack_size)
 569 {
 570         int __user *parent_tid_ptr, *child_tid_ptr;
 571         unsigned long orig_i1 = regs->u_regs[UREG_I1];
 572         long ret;
 573
 574 #ifdef CONFIG_COMPAT
 575         if (test_thread_flag(TIF_32BIT)) {
 576                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 577                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 578         } else
 579 #endif
 580         {
 581                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 582                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 583         }
 584
 585         ret = do_fork(clone_flags, stack_start, stack_size,
 586                       parent_tid_ptr, child_tid_ptr);
 587
 588         /* If we get an error and potentially restart the system
 589          * call, we're screwed because copy_thread() clobbered
 590          * the parent's %o1.  So detect that case and restore it
 591          * here.
 592          */
 593         if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
 594                 regs->u_regs[UREG_I1] = orig_i1;
 595
 596         return ret;
 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(unsigned long clone_flags, unsigned long sp,
 605                 unsigned long arg, struct task_struct *p)
 606 {
 607         struct thread_info *t = task_thread_info(p);
 608         struct pt_regs *regs = current_pt_regs();
 609         struct sparc_stackf *parent_sf;
 610         unsigned long child_stack_sz;
 611         char *child_trap_frame;
 612
 613         /* Calculate offset to stack_frame & pt_regs */
 614         child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
 615         child_trap_frame = (task_stack_page(p) +
 616                             (THREAD_SIZE - child_stack_sz));
 617
 618         t->new_child = 1;
 619         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 620         t->kregs = (struct pt_regs *) (child_trap_frame +
 621                                        sizeof(struct sparc_stackf));
 622         t->fpsaved[0] = 0;
 623
 624         if (unlikely(p->flags & PF_KTHREAD)) {
 625                 memset(child_trap_frame, 0, child_stack_sz);
 626                 __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] =
 627                         (current_pt_regs()->tstate + 1) & TSTATE_CWP;
 628                 t->current_ds = ASI_P;
 629                 t->kregs->u_regs[UREG_G1] = sp; /* function */
 630                 t->kregs->u_regs[UREG_G2] = arg;
 631                 return 0;
 632         }
 633
 634         parent_sf = ((struct sparc_stackf *) regs) - 1;
 635         memcpy(child_trap_frame, parent_sf, child_stack_sz);
 636         if (t->flags & _TIF_32BIT) {
 637                 sp &= 0x00000000ffffffffUL;
 638                 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 639         }
 640         t->kregs->u_regs[UREG_FP] = sp;
 641         __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] =
 642                 (regs->tstate + 1) & TSTATE_CWP;
 643         t->current_ds = ASI_AIUS;
 644         if (sp != regs->u_regs[UREG_FP]) {
 645                 unsigned long csp;
 646
 647                 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 648                 if (!csp)
 649                         return -EFAULT;
 650                 t->kregs->u_regs[UREG_FP] = csp;
 651         }
 652         if (t->utraps)
 653                 t->utraps[0]++;
 654
 655         /* Set the return value for the child. */
 656         t->kregs->u_regs[UREG_I0] = current->pid;
 657         t->kregs->u_regs[UREG_I1] = 1;
 658
 659         /* Set the second return value for the parent. */
 660         regs->u_regs[UREG_I1] = 0;
 661
 662         if (clone_flags & CLONE_SETTLS)
 663                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 664
 665         return 0;
 666 }
 667
 668 typedef struct {
 669         union {
 670                 unsigned int    pr_regs[32];
 671                 unsigned long   pr_dregs[16];
 672         } pr_fr;
 673         unsigned int __unused;
 674         unsigned int    pr_fsr;
 675         unsigned char   pr_qcnt;
 676         unsigned char   pr_q_entrysize;
 677         unsigned char   pr_en;
 678         unsigned int    pr_q[64];
 679 } elf_fpregset_t32;
 680
 681 /*
 682  * fill in the fpu structure for a core dump.
 683  */
 684 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 685 {
 686         unsigned long *kfpregs = current_thread_info()->fpregs;
 687         unsigned long fprs = current_thread_info()->fpsaved[0];
 688
 689         if (test_thread_flag(TIF_32BIT)) {
 690                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 691
 692                 if (fprs & FPRS_DL)
 693                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 694                                sizeof(unsigned int) * 32);
 695                 else
 696                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 697                                sizeof(unsigned int) * 32);
 698                 fpregs32->pr_qcnt = 0;
 699                 fpregs32->pr_q_entrysize = 8;
 700                 memset(&fpregs32->pr_q[0], 0,
 701                        (sizeof(unsigned int) * 64));
 702                 if (fprs & FPRS_FEF) {
 703                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 704                         fpregs32->pr_en = 1;
 705                 } else {
 706                         fpregs32->pr_fsr = 0;
 707                         fpregs32->pr_en = 0;
 708                 }
 709         } else {
 710                 if(fprs & FPRS_DL)
 711                         memcpy(&fpregs->pr_regs[0], kfpregs,
 712                                sizeof(unsigned int) * 32);
 713                 else
 714                         memset(&fpregs->pr_regs[0], 0,
 715                                sizeof(unsigned int) * 32);
 716                 if(fprs & FPRS_DU)
 717                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 718                                sizeof(unsigned int) * 32);
 719                 else
 720                         memset(&fpregs->pr_regs[16], 0,
 721                                sizeof(unsigned int) * 32);
 722                 if(fprs & FPRS_FEF) {
 723                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 724                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 725                 } else {
 726                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 727                 }
 728                 fpregs->pr_fprs = fprs;
 729         }
 730         return 1;
 731 }
 732 EXPORT_SYMBOL(dump_fpu);
 733
 734 unsigned long get_wchan(struct task_struct *task)
 735 {
 736         unsigned long pc, fp, bias = 0;
 737         struct thread_info *tp;
 738         struct reg_window *rw;
 739         unsigned long ret = 0;
 740         int count = 0;
 741
 742         if (!task || task == current ||
 743             task->state == TASK_RUNNING)
 744                 goto out;
 745
 746         tp = task_thread_info(task);
 747         bias = STACK_BIAS;
 748         fp = task_thread_info(task)->ksp + bias;
 749
 750         do {
 751                 if (!kstack_valid(tp, fp))
 752                         break;
 753                 rw = (struct reg_window *) fp;
 754                 pc = rw->ins[7];
 755                 if (!in_sched_functions(pc)) {
 756                         ret = pc;
 757                         goto out;
 758                 }
 759                 fp = rw->ins[6] + bias;
 760         } while (++count < 16);
 761
 762 out:
 763         return ret;
 764 }