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 #include <linux/context_tracking.h>
  35
  36 #include <linux/uaccess.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 #include <asm/syscalls.h>
  50 #include <asm/irq_regs.h>
  51 #include <asm/smp.h>
  52 #include <asm/pcr.h>
  53
  54 #include "kstack.h"
  55
  56 /* Idle loop support on sparc64. */
  57 void arch_cpu_idle(void)
  58 {
  59         if (tlb_type != hypervisor) {
  60                 touch_nmi_watchdog();
  61                 local_irq_enable();
  62         } else {
  63                 unsigned long pstate;
  64
  65                 local_irq_enable();
  66
  67                 /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
  68                  * the cpu sleep hypervisor call.
  69                  */
  70                 __asm__ __volatile__(
  71                         "rdpr %%pstate, %0\n\t"
  72                         "andn %0, %1, %0\n\t"
  73                         "wrpr %0, %%g0, %%pstate"
  74                         : "=&r" (pstate)
  75                         : "i" (PSTATE_IE));
  76
  77                 if (!need_resched() && !cpu_is_offline(smp_processor_id()))
  78                         sun4v_cpu_yield();
  79
  80                 /* Re-enable interrupts. */
  81                 __asm__ __volatile__(
  82                         "rdpr %%pstate, %0\n\t"
  83                         "or %0, %1, %0\n\t"
  84                         "wrpr %0, %%g0, %%pstate"
  85                         : "=&r" (pstate)
  86                         : "i" (PSTATE_IE));
  87         }
  88 }
  89
  90 #ifdef CONFIG_HOTPLUG_CPU
  91 void arch_cpu_idle_dead(void)
  92 {
  93         sched_preempt_enable_no_resched();
  94         cpu_play_dead();
  95 }
  96 #endif
  97
  98 #ifdef CONFIG_COMPAT
  99 static void show_regwindow32(struct pt_regs *regs)
 100 {
 101         struct reg_window32 __user *rw;
 102         struct reg_window32 r_w;
 103         mm_segment_t old_fs;
 104
 105         __asm__ __volatile__ ("flushw");
 106         rw = compat_ptr((unsigned int)regs->u_regs[14]);
 107         old_fs = get_fs();
 108         set_fs (USER_DS);
 109         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 110                 set_fs (old_fs);
 111                 return;
 112         }
 113
 114         set_fs (old_fs);
 115         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
 116                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
 117                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
 118                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
 119         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
 120                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
 121                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
 122                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
 123 }
 124 #else
 125 #define show_regwindow32(regs)  do { } while (0)
 126 #endif
 127
 128 static void show_regwindow(struct pt_regs *regs)
 129 {
 130         struct reg_window __user *rw;
 131         struct reg_window *rwk;
 132         struct reg_window r_w;
 133         mm_segment_t old_fs;
 134
 135         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
 136                 __asm__ __volatile__ ("flushw");
 137                 rw = (struct reg_window __user *)
 138                         (regs->u_regs[14] + STACK_BIAS);
 139                 rwk = (struct reg_window *)
 140                         (regs->u_regs[14] + STACK_BIAS);
 141                 if (!(regs->tstate & TSTATE_PRIV)) {
 142                         old_fs = get_fs();
 143                         set_fs (USER_DS);
 144                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 145                                 set_fs (old_fs);
 146                                 return;
 147                         }
 148                         rwk = &r_w;
 149                         set_fs (old_fs);
 150                 }
 151         } else {
 152                 show_regwindow32(regs);
 153                 return;
 154         }
 155         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
 156                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
 157         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
 158                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
 159         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
 160                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
 161         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
 162                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
 163         if (regs->tstate & TSTATE_PRIV)
 164                 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
 165 }
 166
 167 void show_regs(struct pt_regs *regs)
 168 {
 169         show_regs_print_info(KERN_DEFAULT);
 170
 171         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
 172                regs->tpc, regs->tnpc, regs->y, print_tainted());
 173         printk("TPC: <%pS>\n", (void *) regs->tpc);
 174         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
 175                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
 176                regs->u_regs[3]);
 177         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
 178                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
 179                regs->u_regs[7]);
 180         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
 181                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
 182                regs->u_regs[11]);
 183         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
 184                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
 185                regs->u_regs[15]);
 186         printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
 187         show_regwindow(regs);
 188         show_stack(current, (unsigned long *) regs->u_regs[UREG_FP]);
 189 }
 190
 191 union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
 192 static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
 193
 194 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
 195                               int this_cpu)
 196 {
 197         struct global_reg_snapshot *rp;
 198
 199         flushw_all();
 200
 201         rp = &global_cpu_snapshot[this_cpu].reg;
 202
 203         rp->tstate = regs->tstate;
 204         rp->tpc = regs->tpc;
 205         rp->tnpc = regs->tnpc;
 206         rp->o7 = regs->u_regs[UREG_I7];
 207
 208         if (regs->tstate & TSTATE_PRIV) {
 209                 struct reg_window *rw;
 210
 211                 rw = (struct reg_window *)
 212                         (regs->u_regs[UREG_FP] + STACK_BIAS);
 213                 if (kstack_valid(tp, (unsigned long) rw)) {
 214                         rp->i7 = rw->ins[7];
 215                         rw = (struct reg_window *)
 216                                 (rw->ins[6] + STACK_BIAS);
 217                         if (kstack_valid(tp, (unsigned long) rw))
 218                                 rp->rpc = rw->ins[7];
 219                 }
 220         } else {
 221                 rp->i7 = 0;
 222                 rp->rpc = 0;
 223         }
 224         rp->thread = tp;
 225 }
 226
 227 /* In order to avoid hangs we do not try to synchronize with the
 228  * global register dump client cpus.  The last store they make is to
 229  * the thread pointer, so do a short poll waiting for that to become
 230  * non-NULL.
 231  */
 232 static void __global_reg_poll(struct global_reg_snapshot *gp)
 233 {
 234         int limit = 0;
 235
 236         while (!gp->thread && ++limit < 100) {
 237                 barrier();
 238                 udelay(1);
 239         }
 240 }
 241
 242 void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
 243 {
 244         struct thread_info *tp = current_thread_info();
 245         struct pt_regs *regs = get_irq_regs();
 246         unsigned long flags;
 247         int this_cpu, cpu;
 248
 249         if (!regs)
 250                 regs = tp->kregs;
 251
 252         spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
 253
 254         this_cpu = raw_smp_processor_id();
 255
 256         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
 257
 258         if (cpumask_test_cpu(this_cpu, mask) && !exclude_self)
 259                 __global_reg_self(tp, regs, this_cpu);
 260
 261         smp_fetch_global_regs();
 262
 263         for_each_cpu(cpu, mask) {
 264                 struct global_reg_snapshot *gp;
 265
 266                 if (exclude_self && cpu == this_cpu)
 267                         continue;
 268
 269                 gp = &global_cpu_snapshot[cpu].reg;
 270
 271                 __global_reg_poll(gp);
 272
 273                 tp = gp->thread;
 274                 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
 275                        (cpu == this_cpu ? '*' : ' '), cpu,
 276                        gp->tstate, gp->tpc, gp->tnpc,
 277                        ((tp && tp->task) ? tp->task->comm : "NULL"),
 278                        ((tp && tp->task) ? tp->task->pid : -1));
 279
 280                 if (gp->tstate & TSTATE_PRIV) {
 281                         printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
 282                                (void *) gp->tpc,
 283                                (void *) gp->o7,
 284                                (void *) gp->i7,
 285                                (void *) gp->rpc);
 286                 } else {
 287                         printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
 288                                gp->tpc, gp->o7, gp->i7, gp->rpc);
 289                 }
 290
 291                 touch_nmi_watchdog();
 292         }
 293
 294         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
 295
 296         spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
 297 }
 298
 299 #ifdef CONFIG_MAGIC_SYSRQ
 300
 301 static void sysrq_handle_globreg(int key)
 302 {
 303         trigger_all_cpu_backtrace();
 304 }
 305
 306 static struct sysrq_key_op sparc_globalreg_op = {
 307         .handler        = sysrq_handle_globreg,
 308         .help_msg       = "global-regs(y)",
 309         .action_msg     = "Show Global CPU Regs",
 310 };
 311
 312 static void __global_pmu_self(int this_cpu)
 313 {
 314         struct global_pmu_snapshot *pp;
 315         int i, num;
 316
 317         if (!pcr_ops)
 318                 return;
 319
 320         pp = &global_cpu_snapshot[this_cpu].pmu;
 321
 322         num = 1;
 323         if (tlb_type == hypervisor &&
 324             sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
 325                 num = 4;
 326
 327         for (i = 0; i < num; i++) {
 328                 pp->pcr[i] = pcr_ops->read_pcr(i);
 329                 pp->pic[i] = pcr_ops->read_pic(i);
 330         }
 331 }
 332
 333 static void __global_pmu_poll(struct global_pmu_snapshot *pp)
 334 {
 335         int limit = 0;
 336
 337         while (!pp->pcr[0] && ++limit < 100) {
 338                 barrier();
 339                 udelay(1);
 340         }
 341 }
 342
 343 static void pmu_snapshot_all_cpus(void)
 344 {
 345         unsigned long flags;
 346         int this_cpu, cpu;
 347
 348         spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
 349
 350         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
 351
 352         this_cpu = raw_smp_processor_id();
 353
 354         __global_pmu_self(this_cpu);
 355
 356         smp_fetch_global_pmu();
 357
 358         for_each_online_cpu(cpu) {
 359                 struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
 360
 361                 __global_pmu_poll(pp);
 362
 363                 printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
 364                        (cpu == this_cpu ? '*' : ' '), cpu,
 365                        pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
 366                        pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
 367
 368                 touch_nmi_watchdog();
 369         }
 370
 371         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
 372
 373         spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
 374 }
 375
 376 static void sysrq_handle_globpmu(int key)
 377 {
 378         pmu_snapshot_all_cpus();
 379 }
 380
 381 static struct sysrq_key_op sparc_globalpmu_op = {
 382         .handler        = sysrq_handle_globpmu,
 383         .help_msg       = "global-pmu(x)",
 384         .action_msg     = "Show Global PMU Regs",
 385 };
 386
 387 static int __init sparc_sysrq_init(void)
 388 {
 389         int ret = register_sysrq_key('y', &sparc_globalreg_op);
 390
 391         if (!ret)
 392                 ret = register_sysrq_key('x', &sparc_globalpmu_op);
 393         return ret;
 394 }
 395
 396 core_initcall(sparc_sysrq_init);
 397
 398 #endif
 399
 400 unsigned long thread_saved_pc(struct task_struct *tsk)
 401 {
 402         struct thread_info *ti = task_thread_info(tsk);
 403         unsigned long ret = 0xdeadbeefUL;
 404
 405         if (ti && ti->ksp) {
 406                 unsigned long *sp;
 407                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
 408                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
 409                     sp[14]) {
 410                         unsigned long *fp;
 411                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
 412                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
 413                                 ret = fp[15];
 414                 }
 415         }
 416         return ret;
 417 }
 418
 419 /* Free current thread data structures etc.. */
 420 void exit_thread(struct task_struct *tsk)
 421 {
 422         struct thread_info *t = task_thread_info(tsk);
 423
 424         if (t->utraps) {
 425                 if (t->utraps[0] < 2)
 426                         kfree (t->utraps);
 427                 else
 428                         t->utraps[0]--;
 429         }
 430 }
 431
 432 void flush_thread(void)
 433 {
 434         struct thread_info *t = current_thread_info();
 435         struct mm_struct *mm;
 436
 437         mm = t->task->mm;
 438         if (mm)
 439                 tsb_context_switch(mm);
 440
 441         set_thread_wsaved(0);
 442
 443         /* Clear FPU register state. */
 444         t->fpsaved[0] = 0;
 445 }
 446
 447 /* It's a bit more tricky when 64-bit tasks are involved... */
 448 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 449 {
 450         bool stack_64bit = test_thread_64bit_stack(psp);
 451         unsigned long fp, distance, rval;
 452
 453         if (stack_64bit) {
 454                 csp += STACK_BIAS;
 455                 psp += STACK_BIAS;
 456                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
 457                 fp += STACK_BIAS;
 458                 if (test_thread_flag(TIF_32BIT))
 459                         fp &= 0xffffffff;
 460         } else
 461                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 462
 463         /* Now align the stack as this is mandatory in the Sparc ABI
 464          * due to how register windows work.  This hides the
 465          * restriction from thread libraries etc.
 466          */
 467         csp &= ~15UL;
 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 (!stack_64bit) {
 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                 window -= 1;
 509                 do {
 510                         struct reg_window *rwin = &t->reg_window[window];
 511                         int winsize = sizeof(struct reg_window);
 512                         unsigned long sp;
 513
 514                         sp = t->rwbuf_stkptrs[window];
 515
 516                         if (test_thread_64bit_stack(sp))
 517                                 sp += STACK_BIAS;
 518                         else
 519                                 winsize = sizeof(struct reg_window32);
 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
 546         flush_user_windows();
 547         window = get_thread_wsaved();
 548
 549         if (likely(window != 0)) {
 550                 window -= 1;
 551                 do {
 552                         struct reg_window *rwin = &t->reg_window[window];
 553                         int winsize = sizeof(struct reg_window);
 554                         unsigned long sp;
 555
 556                         sp = t->rwbuf_stkptrs[window];
 557
 558                         if (test_thread_64bit_stack(sp))
 559                                 sp += STACK_BIAS;
 560                         else
 561                                 winsize = sizeof(struct reg_window32);
 562
 563                         if (unlikely(sp & 0x7UL))
 564                                 stack_unaligned(sp);
 565
 566                         if (unlikely(copy_to_user((char __user *)sp,
 567                                                   rwin, winsize)))
 568                                 goto barf;
 569                 } while (window--);
 570         }
 571         set_thread_wsaved(0);
 572         return;
 573
 574 barf:
 575         set_thread_wsaved(window + 1);
 576         user_exit();
 577         do_exit(SIGILL);
 578 }
 579
 580 asmlinkage long sparc_do_fork(unsigned long clone_flags,
 581                               unsigned long stack_start,
 582                               struct pt_regs *regs,
 583                               unsigned long stack_size)
 584 {
 585         int __user *parent_tid_ptr, *child_tid_ptr;
 586         unsigned long orig_i1 = regs->u_regs[UREG_I1];
 587         long ret;
 588
 589 #ifdef CONFIG_COMPAT
 590         if (test_thread_flag(TIF_32BIT)) {
 591                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
 592                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
 593         } else
 594 #endif
 595         {
 596                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
 597                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
 598         }
 599
 600         ret = do_fork(clone_flags, stack_start, stack_size,
 601                       parent_tid_ptr, child_tid_ptr);
 602
 603         /* If we get an error and potentially restart the system
 604          * call, we're screwed because copy_thread() clobbered
 605          * the parent's %o1.  So detect that case and restore it
 606          * here.
 607          */
 608         if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
 609                 regs->u_regs[UREG_I1] = orig_i1;
 610
 611         return ret;
 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(unsigned long clone_flags, unsigned long sp,
 620                 unsigned long arg, struct task_struct *p)
 621 {
 622         struct thread_info *t = task_thread_info(p);
 623         struct pt_regs *regs = current_pt_regs();
 624         struct sparc_stackf *parent_sf;
 625         unsigned long child_stack_sz;
 626         char *child_trap_frame;
 627
 628         /* Calculate offset to stack_frame & pt_regs */
 629         child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
 630         child_trap_frame = (task_stack_page(p) +
 631                             (THREAD_SIZE - child_stack_sz));
 632
 633         t->new_child = 1;
 634         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
 635         t->kregs = (struct pt_regs *) (child_trap_frame +
 636                                        sizeof(struct sparc_stackf));
 637         t->fpsaved[0] = 0;
 638
 639         if (unlikely(p->flags & PF_KTHREAD)) {
 640                 memset(child_trap_frame, 0, child_stack_sz);
 641                 __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] =
 642                         (current_pt_regs()->tstate + 1) & TSTATE_CWP;
 643                 t->current_ds = ASI_P;
 644                 t->kregs->u_regs[UREG_G1] = sp; /* function */
 645                 t->kregs->u_regs[UREG_G2] = arg;
 646                 return 0;
 647         }
 648
 649         parent_sf = ((struct sparc_stackf *) regs) - 1;
 650         memcpy(child_trap_frame, parent_sf, child_stack_sz);
 651         if (t->flags & _TIF_32BIT) {
 652                 sp &= 0x00000000ffffffffUL;
 653                 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 654         }
 655         t->kregs->u_regs[UREG_FP] = sp;
 656         __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] =
 657                 (regs->tstate + 1) & TSTATE_CWP;
 658         t->current_ds = ASI_AIUS;
 659         if (sp != regs->u_regs[UREG_FP]) {
 660                 unsigned long csp;
 661
 662                 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
 663                 if (!csp)
 664                         return -EFAULT;
 665                 t->kregs->u_regs[UREG_FP] = csp;
 666         }
 667         if (t->utraps)
 668                 t->utraps[0]++;
 669
 670         /* Set the return value for the child. */
 671         t->kregs->u_regs[UREG_I0] = current->pid;
 672         t->kregs->u_regs[UREG_I1] = 1;
 673
 674         /* Set the second return value for the parent. */
 675         regs->u_regs[UREG_I1] = 0;
 676
 677         if (clone_flags & CLONE_SETTLS)
 678                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
 679
 680         return 0;
 681 }
 682
 683 typedef struct {
 684         union {
 685                 unsigned int    pr_regs[32];
 686                 unsigned long   pr_dregs[16];
 687         } pr_fr;
 688         unsigned int __unused;
 689         unsigned int    pr_fsr;
 690         unsigned char   pr_qcnt;
 691         unsigned char   pr_q_entrysize;
 692         unsigned char   pr_en;
 693         unsigned int    pr_q[64];
 694 } elf_fpregset_t32;
 695
 696 /*
 697  * fill in the fpu structure for a core dump.
 698  */
 699 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
 700 {
 701         unsigned long *kfpregs = current_thread_info()->fpregs;
 702         unsigned long fprs = current_thread_info()->fpsaved[0];
 703
 704         if (test_thread_flag(TIF_32BIT)) {
 705                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
 706
 707                 if (fprs & FPRS_DL)
 708                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
 709                                sizeof(unsigned int) * 32);
 710                 else
 711                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
 712                                sizeof(unsigned int) * 32);
 713                 fpregs32->pr_qcnt = 0;
 714                 fpregs32->pr_q_entrysize = 8;
 715                 memset(&fpregs32->pr_q[0], 0,
 716                        (sizeof(unsigned int) * 64));
 717                 if (fprs & FPRS_FEF) {
 718                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
 719                         fpregs32->pr_en = 1;
 720                 } else {
 721                         fpregs32->pr_fsr = 0;
 722                         fpregs32->pr_en = 0;
 723                 }
 724         } else {
 725                 if(fprs & FPRS_DL)
 726                         memcpy(&fpregs->pr_regs[0], kfpregs,
 727                                sizeof(unsigned int) * 32);
 728                 else
 729                         memset(&fpregs->pr_regs[0], 0,
 730                                sizeof(unsigned int) * 32);
 731                 if(fprs & FPRS_DU)
 732                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
 733                                sizeof(unsigned int) * 32);
 734                 else
 735                         memset(&fpregs->pr_regs[16], 0,
 736                                sizeof(unsigned int) * 32);
 737                 if(fprs & FPRS_FEF) {
 738                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
 739                         fpregs->pr_gsr = current_thread_info()->gsr[0];
 740                 } else {
 741                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
 742                 }
 743                 fpregs->pr_fprs = fprs;
 744         }
 745         return 1;
 746 }
 747 EXPORT_SYMBOL(dump_fpu);
 748
 749 unsigned long get_wchan(struct task_struct *task)
 750 {
 751         unsigned long pc, fp, bias = 0;
 752         struct thread_info *tp;
 753         struct reg_window *rw;
 754         unsigned long ret = 0;
 755         int count = 0;
 756
 757         if (!task || task == current ||
 758             task->state == TASK_RUNNING)
 759                 goto out;
 760
 761         tp = task_thread_info(task);
 762         bias = STACK_BIAS;
 763         fp = task_thread_info(task)->ksp + bias;
 764
 765         do {
 766                 if (!kstack_valid(tp, fp))
 767                         break;
 768                 rw = (struct reg_window *) fp;
 769                 pc = rw->ins[7];
 770                 if (!in_sched_functions(pc)) {
 771                         ret = pc;
 772                         goto out;
 773                 }
 774                 fp = rw->ins[6] + bias;
 775         } while (++count < 16);
 776
 777 out:
 778         return ret;
 779 }