arch/powerpc/kernel/process.c

   1 /*
   2  *  Derived from "arch/i386/kernel/process.c"
   3  *    Copyright (C) 1995  Linus Torvalds
   4  *
   5  *  Updated and modified by Cort Dougan (cort@cs.nmt.edu) and
   6  *  Paul Mackerras (paulus@cs.anu.edu.au)
   7  *
   8  *  PowerPC version
   9  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  10  *
  11  *  This program is free software; you can redistribute it and/or
  12  *  modify it under the terms of the GNU General Public License
  13  *  as published by the Free Software Foundation; either version
  14  *  2 of the License, or (at your option) any later version.
  15  */
  16
  17 #include <linux/errno.h>
  18 #include <linux/sched.h>
  19 #include <linux/kernel.h>
  20 #include <linux/mm.h>
  21 #include <linux/smp.h>
  22 #include <linux/stddef.h>
  23 #include <linux/unistd.h>
  24 #include <linux/ptrace.h>
  25 #include <linux/slab.h>
  26 #include <linux/user.h>
  27 #include <linux/elf.h>
  28 #include <linux/init.h>
  29 #include <linux/prctl.h>
  30 #include <linux/init_task.h>
  31 #include <linux/module.h>
  32 #include <linux/kallsyms.h>
  33 #include <linux/mqueue.h>
  34 #include <linux/hardirq.h>
  35 #include <linux/utsname.h>
  36 #include <linux/ftrace.h>
  37 #include <linux/kernel_stat.h>
  38 #include <linux/personality.h>
  39 #include <linux/random.h>
  40 #include <linux/hw_breakpoint.h>
  41
  42 #include <asm/pgtable.h>
  43 #include <asm/uaccess.h>
  44 #include <asm/system.h>
  45 #include <asm/io.h>
  46 #include <asm/processor.h>
  47 #include <asm/mmu.h>
  48 #include <asm/prom.h>
  49 #include <asm/machdep.h>
  50 #include <asm/time.h>
  51 #include <asm/syscalls.h>
  52 #ifdef CONFIG_PPC64
  53 #include <asm/firmware.h>
  54 #endif
  55 #include <linux/kprobes.h>
  56 #include <linux/kdebug.h>
  57
  58 extern unsigned long _get_SP(void);
  59
  60 #ifndef CONFIG_SMP
  61 struct task_struct *last_task_used_math = NULL;
  62 struct task_struct *last_task_used_altivec = NULL;
  63 struct task_struct *last_task_used_vsx = NULL;
  64 struct task_struct *last_task_used_spe = NULL;
  65 #endif
  66
  67 /*
  68  * Make sure the floating-point register state in the
  69  * the thread_struct is up to date for task tsk.
  70  */
  71 void flush_fp_to_thread(struct task_struct *tsk)
  72 {
  73         if (tsk->thread.regs) {
  74                 /*
  75                  * We need to disable preemption here because if we didn't,
  76                  * another process could get scheduled after the regs->msr
  77                  * test but before we have finished saving the FP registers
  78                  * to the thread_struct.  That process could take over the
  79                  * FPU, and then when we get scheduled again we would store
  80                  * bogus values for the remaining FP registers.
  81                  */
  82                 preempt_disable();
  83                 if (tsk->thread.regs->msr & MSR_FP) {
  84 #ifdef CONFIG_SMP
  85                         /*
  86                          * This should only ever be called for current or
  87                          * for a stopped child process.  Since we save away
  88                          * the FP register state on context switch on SMP,
  89                          * there is something wrong if a stopped child appears
  90                          * to still have its FP state in the CPU registers.
  91                          */
  92                         BUG_ON(tsk != current);
  93 #endif
  94                         giveup_fpu(tsk);
  95                 }
  96                 preempt_enable();
  97         }
  98 }
  99
 100 void enable_kernel_fp(void)
 101 {
 102         WARN_ON(preemptible());
 103
 104 #ifdef CONFIG_SMP
 105         if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
 106                 giveup_fpu(current);
 107         else
 108                 giveup_fpu(NULL);       /* just enables FP for kernel */
 109 #else
 110         giveup_fpu(last_task_used_math);
 111 #endif /* CONFIG_SMP */
 112 }
 113 EXPORT_SYMBOL(enable_kernel_fp);
 114
 115 #ifdef CONFIG_ALTIVEC
 116 void enable_kernel_altivec(void)
 117 {
 118         WARN_ON(preemptible());
 119
 120 #ifdef CONFIG_SMP
 121         if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
 122                 giveup_altivec(current);
 123         else
 124                 giveup_altivec(NULL);   /* just enable AltiVec for kernel - force */
 125 #else
 126         giveup_altivec(last_task_used_altivec);
 127 #endif /* CONFIG_SMP */
 128 }
 129 EXPORT_SYMBOL(enable_kernel_altivec);
 130
 131 /*
 132  * Make sure the VMX/Altivec register state in the
 133  * the thread_struct is up to date for task tsk.
 134  */
 135 void flush_altivec_to_thread(struct task_struct *tsk)
 136 {
 137         if (tsk->thread.regs) {
 138                 preempt_disable();
 139                 if (tsk->thread.regs->msr & MSR_VEC) {
 140 #ifdef CONFIG_SMP
 141                         BUG_ON(tsk != current);
 142 #endif
 143                         giveup_altivec(tsk);
 144                 }
 145                 preempt_enable();
 146         }
 147 }
 148 #endif /* CONFIG_ALTIVEC */
 149
 150 #ifdef CONFIG_VSX
 151 #if 0
 152 /* not currently used, but some crazy RAID module might want to later */
 153 void enable_kernel_vsx(void)
 154 {
 155         WARN_ON(preemptible());
 156
 157 #ifdef CONFIG_SMP
 158         if (current->thread.regs && (current->thread.regs->msr & MSR_VSX))
 159                 giveup_vsx(current);
 160         else
 161                 giveup_vsx(NULL);       /* just enable vsx for kernel - force */
 162 #else
 163         giveup_vsx(last_task_used_vsx);
 164 #endif /* CONFIG_SMP */
 165 }
 166 EXPORT_SYMBOL(enable_kernel_vsx);
 167 #endif
 168
 169 void giveup_vsx(struct task_struct *tsk)
 170 {
 171         giveup_fpu(tsk);
 172         giveup_altivec(tsk);
 173         __giveup_vsx(tsk);
 174 }
 175
 176 void flush_vsx_to_thread(struct task_struct *tsk)
 177 {
 178         if (tsk->thread.regs) {
 179                 preempt_disable();
 180                 if (tsk->thread.regs->msr & MSR_VSX) {
 181 #ifdef CONFIG_SMP
 182                         BUG_ON(tsk != current);
 183 #endif
 184                         giveup_vsx(tsk);
 185                 }
 186                 preempt_enable();
 187         }
 188 }
 189 #endif /* CONFIG_VSX */
 190
 191 #ifdef CONFIG_SPE
 192
 193 void enable_kernel_spe(void)
 194 {
 195         WARN_ON(preemptible());
 196
 197 #ifdef CONFIG_SMP
 198         if (current->thread.regs && (current->thread.regs->msr & MSR_SPE))
 199                 giveup_spe(current);
 200         else
 201                 giveup_spe(NULL);       /* just enable SPE for kernel - force */
 202 #else
 203         giveup_spe(last_task_used_spe);
 204 #endif /* __SMP __ */
 205 }
 206 EXPORT_SYMBOL(enable_kernel_spe);
 207
 208 void flush_spe_to_thread(struct task_struct *tsk)
 209 {
 210         if (tsk->thread.regs) {
 211                 preempt_disable();
 212                 if (tsk->thread.regs->msr & MSR_SPE) {
 213 #ifdef CONFIG_SMP
 214                         BUG_ON(tsk != current);
 215 #endif
 216                         giveup_spe(tsk);
 217                 }
 218                 preempt_enable();
 219         }
 220 }
 221 #endif /* CONFIG_SPE */
 222
 223 #ifndef CONFIG_SMP
 224 /*
 225  * If we are doing lazy switching of CPU state (FP, altivec or SPE),
 226  * and the current task has some state, discard it.
 227  */
 228 void discard_lazy_cpu_state(void)
 229 {
 230         preempt_disable();
 231         if (last_task_used_math == current)
 232                 last_task_used_math = NULL;
 233 #ifdef CONFIG_ALTIVEC
 234         if (last_task_used_altivec == current)
 235                 last_task_used_altivec = NULL;
 236 #endif /* CONFIG_ALTIVEC */
 237 #ifdef CONFIG_VSX
 238         if (last_task_used_vsx == current)
 239                 last_task_used_vsx = NULL;
 240 #endif /* CONFIG_VSX */
 241 #ifdef CONFIG_SPE
 242         if (last_task_used_spe == current)
 243                 last_task_used_spe = NULL;
 244 #endif
 245         preempt_enable();
 246 }
 247 #endif /* CONFIG_SMP */
 248
 249 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 250 void do_send_trap(struct pt_regs *regs, unsigned long address,
 251                   unsigned long error_code, int signal_code, int breakpt)
 252 {
 253         siginfo_t info;
 254
 255         if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
 256                         11, SIGSEGV) == NOTIFY_STOP)
 257                 return;
 258
 259         /* Deliver the signal to userspace */
 260         info.si_signo = SIGTRAP;
 261         info.si_errno = breakpt;        /* breakpoint or watchpoint id */
 262         info.si_code = signal_code;
 263         info.si_addr = (void __user *)address;
 264         force_sig_info(SIGTRAP, &info, current);
 265 }
 266 #else   /* !CONFIG_PPC_ADV_DEBUG_REGS */
 267 void do_dabr(struct pt_regs *regs, unsigned long address,
 268                     unsigned long error_code)
 269 {
 270         siginfo_t info;
 271
 272         if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
 273                         11, SIGSEGV) == NOTIFY_STOP)
 274                 return;
 275
 276         if (debugger_dabr_match(regs))
 277                 return;
 278
 279         /* Clear the DABR */
 280         set_dabr(0);
 281
 282         /* Deliver the signal to userspace */
 283         info.si_signo = SIGTRAP;
 284         info.si_errno = 0;
 285         info.si_code = TRAP_HWBKPT;
 286         info.si_addr = (void __user *)address;
 287         force_sig_info(SIGTRAP, &info, current);
 288 }
 289 #endif  /* CONFIG_PPC_ADV_DEBUG_REGS */
 290
 291 static DEFINE_PER_CPU(unsigned long, current_dabr);
 292
 293 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 294 /*
 295  * Set the debug registers back to their default "safe" values.
 296  */
 297 static void set_debug_reg_defaults(struct thread_struct *thread)
 298 {
 299         thread->iac1 = thread->iac2 = 0;
 300 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
 301         thread->iac3 = thread->iac4 = 0;
 302 #endif
 303         thread->dac1 = thread->dac2 = 0;
 304 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
 305         thread->dvc1 = thread->dvc2 = 0;
 306 #endif
 307         thread->dbcr0 = 0;
 308 #ifdef CONFIG_BOOKE
 309         /*
 310          * Force User/Supervisor bits to b11 (user-only MSR[PR]=1)
 311          */
 312         thread->dbcr1 = DBCR1_IAC1US | DBCR1_IAC2US |   \
 313                         DBCR1_IAC3US | DBCR1_IAC4US;
 314         /*
 315          * Force Data Address Compare User/Supervisor bits to be User-only
 316          * (0b11 MSR[PR]=1) and set all other bits in DBCR2 register to be 0.
 317          */
 318         thread->dbcr2 = DBCR2_DAC1US | DBCR2_DAC2US;
 319 #else
 320         thread->dbcr1 = 0;
 321 #endif
 322 }
 323
 324 static void prime_debug_regs(struct thread_struct *thread)
 325 {
 326         mtspr(SPRN_IAC1, thread->iac1);
 327         mtspr(SPRN_IAC2, thread->iac2);
 328 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
 329         mtspr(SPRN_IAC3, thread->iac3);
 330         mtspr(SPRN_IAC4, thread->iac4);
 331 #endif
 332         mtspr(SPRN_DAC1, thread->dac1);
 333         mtspr(SPRN_DAC2, thread->dac2);
 334 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
 335         mtspr(SPRN_DVC1, thread->dvc1);
 336         mtspr(SPRN_DVC2, thread->dvc2);
 337 #endif
 338         mtspr(SPRN_DBCR0, thread->dbcr0);
 339         mtspr(SPRN_DBCR1, thread->dbcr1);
 340 #ifdef CONFIG_BOOKE
 341         mtspr(SPRN_DBCR2, thread->dbcr2);
 342 #endif
 343 }
 344 /*
 345  * Unless neither the old or new thread are making use of the
 346  * debug registers, set the debug registers from the values
 347  * stored in the new thread.
 348  */
 349 static void switch_booke_debug_regs(struct thread_struct *new_thread)
 350 {
 351         if ((current->thread.dbcr0 & DBCR0_IDM)
 352                 || (new_thread->dbcr0 & DBCR0_IDM))
 353                         prime_debug_regs(new_thread);
 354 }
 355 #else   /* !CONFIG_PPC_ADV_DEBUG_REGS */
 356 static void set_debug_reg_defaults(struct thread_struct *thread)
 357 {
 358         if (thread->dabr) {
 359                 thread->dabr = 0;
 360                 set_dabr(0);
 361         }
 362 }
 363 #endif  /* CONFIG_PPC_ADV_DEBUG_REGS */
 364
 365 int set_dabr(unsigned long dabr)
 366 {
 367         __get_cpu_var(current_dabr) = dabr;
 368
 369         if (ppc_md.set_dabr)
 370                 return ppc_md.set_dabr(dabr);
 371
 372         /* XXX should we have a CPU_FTR_HAS_DABR ? */
 373 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 374         mtspr(SPRN_DAC1, dabr);
 375 #ifdef CONFIG_PPC_47x
 376         isync();
 377 #endif
 378 #elif defined(CONFIG_PPC_BOOK3S)
 379         mtspr(SPRN_DABR, dabr);
 380 #endif
 381
 382
 383         return 0;
 384 }
 385
 386 #ifdef CONFIG_PPC64
 387 DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
 388 #endif
 389
 390 struct task_struct *__switch_to(struct task_struct *prev,
 391         struct task_struct *new)
 392 {
 393         struct thread_struct *new_thread, *old_thread;
 394         unsigned long flags;
 395         struct task_struct *last;
 396
 397 #ifdef CONFIG_SMP
 398         /* avoid complexity of lazy save/restore of fpu
 399          * by just saving it every time we switch out if
 400          * this task used the fpu during the last quantum.
 401          *
 402          * If it tries to use the fpu again, it'll trap and
 403          * reload its fp regs.  So we don't have to do a restore
 404          * every switch, just a save.
 405          *  -- Cort
 406          */
 407         if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
 408                 giveup_fpu(prev);
 409 #ifdef CONFIG_ALTIVEC
 410         /*
 411          * If the previous thread used altivec in the last quantum
 412          * (thus changing altivec regs) then save them.
 413          * We used to check the VRSAVE register but not all apps
 414          * set it, so we don't rely on it now (and in fact we need
 415          * to save & restore VSCR even if VRSAVE == 0).  -- paulus
 416          *
 417          * On SMP we always save/restore altivec regs just to avoid the
 418          * complexity of changing processors.
 419          *  -- Cort
 420          */
 421         if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
 422                 giveup_altivec(prev);
 423 #endif /* CONFIG_ALTIVEC */
 424 #ifdef CONFIG_VSX
 425         if (prev->thread.regs && (prev->thread.regs->msr & MSR_VSX))
 426                 /* VMX and FPU registers are already save here */
 427                 __giveup_vsx(prev);
 428 #endif /* CONFIG_VSX */
 429 #ifdef CONFIG_SPE
 430         /*
 431          * If the previous thread used spe in the last quantum
 432          * (thus changing spe regs) then save them.
 433          *
 434          * On SMP we always save/restore spe regs just to avoid the
 435          * complexity of changing processors.
 436          */
 437         if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE)))
 438                 giveup_spe(prev);
 439 #endif /* CONFIG_SPE */
 440
 441 #else  /* CONFIG_SMP */
 442 #ifdef CONFIG_ALTIVEC
 443         /* Avoid the trap.  On smp this this never happens since
 444          * we don't set last_task_used_altivec -- Cort
 445          */
 446         if (new->thread.regs && last_task_used_altivec == new)
 447                 new->thread.regs->msr |= MSR_VEC;
 448 #endif /* CONFIG_ALTIVEC */
 449 #ifdef CONFIG_VSX
 450         if (new->thread.regs && last_task_used_vsx == new)
 451                 new->thread.regs->msr |= MSR_VSX;
 452 #endif /* CONFIG_VSX */
 453 #ifdef CONFIG_SPE
 454         /* Avoid the trap.  On smp this this never happens since
 455          * we don't set last_task_used_spe
 456          */
 457         if (new->thread.regs && last_task_used_spe == new)
 458                 new->thread.regs->msr |= MSR_SPE;
 459 #endif /* CONFIG_SPE */
 460
 461 #endif /* CONFIG_SMP */
 462
 463 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 464         switch_booke_debug_regs(&new->thread);
 465 #else
 466 /*
 467  * For PPC_BOOK3S_64, we use the hw-breakpoint interfaces that would
 468  * schedule DABR
 469  */
 470 #ifndef CONFIG_HAVE_HW_BREAKPOINT
 471         if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr))
 472                 set_dabr(new->thread.dabr);
 473 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
 474 #endif
 475
 476
 477         new_thread = &new->thread;
 478         old_thread = &current->thread;
 479
 480 #ifdef CONFIG_PPC64
 481         /*
 482          * Collect processor utilization data per process
 483          */
 484         if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
 485                 struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
 486                 long unsigned start_tb, current_tb;
 487                 start_tb = old_thread->start_tb;
 488                 cu->current_tb = current_tb = mfspr(SPRN_PURR);
 489                 old_thread->accum_tb += (current_tb - start_tb);
 490                 new_thread->start_tb = current_tb;
 491         }
 492 #endif
 493
 494         local_irq_save(flags);
 495
 496         account_system_vtime(current);
 497         account_process_vtime(current);
 498         calculate_steal_time();
 499
 500         /*
 501          * We can't take a PMU exception inside _switch() since there is a
 502          * window where the kernel stack SLB and the kernel stack are out
 503          * of sync. Hard disable here.
 504          */
 505         hard_irq_disable();
 506         last = _switch(old_thread, new_thread);
 507
 508         local_irq_restore(flags);
 509
 510         return last;
 511 }
 512
 513 static int instructions_to_print = 16;
 514
 515 static void show_instructions(struct pt_regs *regs)
 516 {
 517         int i;
 518         unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
 519                         sizeof(int));
 520
 521         printk("Instruction dump:");
 522
 523         for (i = 0; i < instructions_to_print; i++) {
 524                 int instr;
 525
 526                 if (!(i % 8))
 527                         printk("\n");
 528
 529 #if !defined(CONFIG_BOOKE)
 530                 /* If executing with the IMMU off, adjust pc rather
 531                  * than print XXXXXXXX.
 532                  */
 533                 if (!(regs->msr & MSR_IR))
 534                         pc = (unsigned long)phys_to_virt(pc);
 535 #endif
 536
 537                 /* We use __get_user here *only* to avoid an OOPS on a
 538                  * bad address because the pc *should* only be a
 539                  * kernel address.
 540                  */
 541                 if (!__kernel_text_address(pc) ||
 542                      __get_user(instr, (unsigned int __user *)pc)) {
 543                         printk("XXXXXXXX ");
 544                 } else {
 545                         if (regs->nip == pc)
 546                                 printk("<%08x> ", instr);
 547                         else
 548                                 printk("%08x ", instr);
 549                 }
 550
 551                 pc += sizeof(int);
 552         }
 553
 554         printk("\n");
 555 }
 556
 557 static struct regbit {
 558         unsigned long bit;
 559         const char *name;
 560 } msr_bits[] = {
 561         {MSR_EE,        "EE"},
 562         {MSR_PR,        "PR"},
 563         {MSR_FP,        "FP"},
 564         {MSR_VEC,       "VEC"},
 565         {MSR_VSX,       "VSX"},
 566         {MSR_ME,        "ME"},
 567         {MSR_CE,        "CE"},
 568         {MSR_DE,        "DE"},
 569         {MSR_IR,        "IR"},
 570         {MSR_DR,        "DR"},
 571         {0,             NULL}
 572 };
 573
 574 static void printbits(unsigned long val, struct regbit *bits)
 575 {
 576         const char *sep = "";
 577
 578         printk("<");
 579         for (; bits->bit; ++bits)
 580                 if (val & bits->bit) {
 581                         printk("%s%s", sep, bits->name);
 582                         sep = ",";
 583                 }
 584         printk(">");
 585 }
 586
 587 #ifdef CONFIG_PPC64
 588 #define REG             "%016lx"
 589 #define REGS_PER_LINE   4
 590 #define LAST_VOLATILE   13
 591 #else
 592 #define REG             "%08lx"
 593 #define REGS_PER_LINE   8
 594 #define LAST_VOLATILE   12
 595 #endif
 596
 597 void show_regs(struct pt_regs * regs)
 598 {
 599         int i, trap;
 600
 601         printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
 602                regs->nip, regs->link, regs->ctr);
 603         printk("REGS: %p TRAP: %04lx   %s  (%s)\n",
 604                regs, regs->trap, print_tainted(), init_utsname()->release);
 605         printk("MSR: "REG" ", regs->msr);
 606         printbits(regs->msr, msr_bits);
 607         printk("  CR: %08lx  XER: %08lx\n", regs->ccr, regs->xer);
 608         trap = TRAP(regs);
 609         if (trap == 0x300 || trap == 0x600)
 610 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 611                 printk("DEAR: "REG", ESR: "REG"\n", regs->dar, regs->dsisr);
 612 #else
 613                 printk("DAR: "REG", DSISR: "REG"\n", regs->dar, regs->dsisr);
 614 #endif
 615         printk("TASK = %p[%d] '%s' THREAD: %p",
 616                current, task_pid_nr(current), current->comm, task_thread_info(current));
 617
 618 #ifdef CONFIG_SMP
 619         printk(" CPU: %d", raw_smp_processor_id());
 620 #endif /* CONFIG_SMP */
 621
 622         for (i = 0;  i < 32;  i++) {
 623                 if ((i % REGS_PER_LINE) == 0)
 624                         printk("\nGPR%02d: ", i);
 625                 printk(REG " ", regs->gpr[i]);
 626                 if (i == LAST_VOLATILE && !FULL_REGS(regs))
 627                         break;
 628         }
 629         printk("\n");
 630 #ifdef CONFIG_KALLSYMS
 631         /*
 632          * Lookup NIP late so we have the best change of getting the
 633          * above info out without failing
 634          */
 635         printk("NIP ["REG"] %pS\n", regs->nip, (void *)regs->nip);
 636         printk("LR ["REG"] %pS\n", regs->link, (void *)regs->link);
 637 #endif
 638         show_stack(current, (unsigned long *) regs->gpr[1]);
 639         if (!user_mode(regs))
 640                 show_instructions(regs);
 641 }
 642
 643 void exit_thread(void)
 644 {
 645         discard_lazy_cpu_state();
 646 }
 647
 648 void flush_thread(void)
 649 {
 650         discard_lazy_cpu_state();
 651
 652 #ifdef CONFIG_HAVE_HW_BREAKPOINTS
 653         flush_ptrace_hw_breakpoint(current);
 654 #else /* CONFIG_HAVE_HW_BREAKPOINTS */
 655         set_debug_reg_defaults(&current->thread);
 656 #endif /* CONFIG_HAVE_HW_BREAKPOINTS */
 657 }
 658
 659 void
 660 release_thread(struct task_struct *t)
 661 {
 662 }
 663
 664 /*
 665  * This gets called before we allocate a new thread and copy
 666  * the current task into it.
 667  */
 668 void prepare_to_copy(struct task_struct *tsk)
 669 {
 670         flush_fp_to_thread(current);
 671         flush_altivec_to_thread(current);
 672         flush_vsx_to_thread(current);
 673         flush_spe_to_thread(current);
 674 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 675         flush_ptrace_hw_breakpoint(tsk);
 676 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
 677 }
 678
 679 /*
 680  * Copy a thread..
 681  */
 682 int copy_thread(unsigned long clone_flags, unsigned long usp,
 683                 unsigned long unused, struct task_struct *p,
 684                 struct pt_regs *regs)
 685 {
 686         struct pt_regs *childregs, *kregs;
 687         extern void ret_from_fork(void);
 688         unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
 689
 690         CHECK_FULL_REGS(regs);
 691         /* Copy registers */
 692         sp -= sizeof(struct pt_regs);
 693         childregs = (struct pt_regs *) sp;
 694         *childregs = *regs;
 695         if ((childregs->msr & MSR_PR) == 0) {
 696                 /* for kernel thread, set `current' and stackptr in new task */
 697                 childregs->gpr[1] = sp + sizeof(struct pt_regs);
 698 #ifdef CONFIG_PPC32
 699                 childregs->gpr[2] = (unsigned long) p;
 700 #else
 701                 clear_tsk_thread_flag(p, TIF_32BIT);
 702 #endif
 703                 p->thread.regs = NULL;  /* no user register state */
 704         } else {
 705                 childregs->gpr[1] = usp;
 706                 p->thread.regs = childregs;
 707                 if (clone_flags & CLONE_SETTLS) {
 708 #ifdef CONFIG_PPC64
 709                         if (!test_thread_flag(TIF_32BIT))
 710                                 childregs->gpr[13] = childregs->gpr[6];
 711                         else
 712 #endif
 713                                 childregs->gpr[2] = childregs->gpr[6];
 714                 }
 715         }
 716         childregs->gpr[3] = 0;  /* Result from fork() */
 717         sp -= STACK_FRAME_OVERHEAD;
 718
 719         /*
 720          * The way this works is that at some point in the future
 721          * some task will call _switch to switch to the new task.
 722          * That will pop off the stack frame created below and start
 723          * the new task running at ret_from_fork.  The new task will
 724          * do some house keeping and then return from the fork or clone
 725          * system call, using the stack frame created above.
 726          */
 727         sp -= sizeof(struct pt_regs);
 728         kregs = (struct pt_regs *) sp;
 729         sp -= STACK_FRAME_OVERHEAD;
 730         p->thread.ksp = sp;
 731         p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
 732                                 _ALIGN_UP(sizeof(struct thread_info), 16);
 733
 734 #ifdef CONFIG_PPC_STD_MMU_64
 735         if (cpu_has_feature(CPU_FTR_SLB)) {
 736                 unsigned long sp_vsid;
 737                 unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
 738
 739                 if (cpu_has_feature(CPU_FTR_1T_SEGMENT))
 740                         sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_1T)
 741                                 << SLB_VSID_SHIFT_1T;
 742                 else
 743                         sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_256M)
 744                                 << SLB_VSID_SHIFT;
 745                 sp_vsid |= SLB_VSID_KERNEL | llp;
 746                 p->thread.ksp_vsid = sp_vsid;
 747         }
 748 #endif /* CONFIG_PPC_STD_MMU_64 */
 749
 750         /*
 751          * The PPC64 ABI makes use of a TOC to contain function
 752          * pointers.  The function (ret_from_except) is actually a pointer
 753          * to the TOC entry.  The first entry is a pointer to the actual
 754          * function.
 755          */
 756 #ifdef CONFIG_PPC64
 757         kregs->nip = *((unsigned long *)ret_from_fork);
 758 #else
 759         kregs->nip = (unsigned long)ret_from_fork;
 760 #endif
 761
 762         return 0;
 763 }
 764
 765 /*
 766  * Set up a thread for executing a new program
 767  */
 768 void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
 769 {
 770 #ifdef CONFIG_PPC64
 771         unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
 772 #endif
 773
 774         set_fs(USER_DS);
 775
 776         /*
 777          * If we exec out of a kernel thread then thread.regs will not be
 778          * set.  Do it now.
 779          */
 780         if (!current->thread.regs) {
 781                 struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
 782                 current->thread.regs = regs - 1;
 783         }
 784
 785         memset(regs->gpr, 0, sizeof(regs->gpr));
 786         regs->ctr = 0;
 787         regs->link = 0;
 788         regs->xer = 0;
 789         regs->ccr = 0;
 790         regs->gpr[1] = sp;
 791
 792         /*
 793          * We have just cleared all the nonvolatile GPRs, so make
 794          * FULL_REGS(regs) return true.  This is necessary to allow
 795          * ptrace to examine the thread immediately after exec.
 796          */
 797         regs->trap &= ~1UL;
 798
 799 #ifdef CONFIG_PPC32
 800         regs->mq = 0;
 801         regs->nip = start;
 802         regs->msr = MSR_USER;
 803 #else
 804         if (!test_thread_flag(TIF_32BIT)) {
 805                 unsigned long entry, toc;
 806
 807                 /* start is a relocated pointer to the function descriptor for
 808                  * the elf _start routine.  The first entry in the function
 809                  * descriptor is the entry address of _start and the second
 810                  * entry is the TOC value we need to use.
 811                  */
 812                 __get_user(entry, (unsigned long __user *)start);
 813                 __get_user(toc, (unsigned long __user *)start+1);
 814
 815                 /* Check whether the e_entry function descriptor entries
 816                  * need to be relocated before we can use them.
 817                  */
 818                 if (load_addr != 0) {
 819                         entry += load_addr;
 820                         toc   += load_addr;
 821                 }
 822                 regs->nip = entry;
 823                 regs->gpr[2] = toc;
 824                 regs->msr = MSR_USER64;
 825         } else {
 826                 regs->nip = start;
 827                 regs->gpr[2] = 0;
 828                 regs->msr = MSR_USER32;
 829         }
 830 #endif
 831
 832         discard_lazy_cpu_state();
 833 #ifdef CONFIG_VSX
 834         current->thread.used_vsr = 0;
 835 #endif
 836         memset(current->thread.fpr, 0, sizeof(current->thread.fpr));
 837         current->thread.fpscr.val = 0;
 838 #ifdef CONFIG_ALTIVEC
 839         memset(current->thread.vr, 0, sizeof(current->thread.vr));
 840         memset(&current->thread.vscr, 0, sizeof(current->thread.vscr));
 841         current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */
 842         current->thread.vrsave = 0;
 843         current->thread.used_vr = 0;
 844 #endif /* CONFIG_ALTIVEC */
 845 #ifdef CONFIG_SPE
 846         memset(current->thread.evr, 0, sizeof(current->thread.evr));
 847         current->thread.acc = 0;
 848         current->thread.spefscr = 0;
 849         current->thread.used_spe = 0;
 850 #endif /* CONFIG_SPE */
 851 }
 852
 853 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
 854                 | PR_FP_EXC_RES | PR_FP_EXC_INV)
 855
 856 int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
 857 {
 858         struct pt_regs *regs = tsk->thread.regs;
 859
 860         /* This is a bit hairy.  If we are an SPE enabled  processor
 861          * (have embedded fp) we store the IEEE exception enable flags in
 862          * fpexc_mode.  fpexc_mode is also used for setting FP exception
 863          * mode (asyn, precise, disabled) for 'Classic' FP. */
 864         if (val & PR_FP_EXC_SW_ENABLE) {
 865 #ifdef CONFIG_SPE
 866                 if (cpu_has_feature(CPU_FTR_SPE)) {
 867                         tsk->thread.fpexc_mode = val &
 868                                 (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
 869                         return 0;
 870                 } else {
 871                         return -EINVAL;
 872                 }
 873 #else
 874                 return -EINVAL;
 875 #endif
 876         }
 877
 878         /* on a CONFIG_SPE this does not hurt us.  The bits that
 879          * __pack_fe01 use do not overlap with bits used for
 880          * PR_FP_EXC_SW_ENABLE.  Additionally, the MSR[FE0,FE1] bits
 881          * on CONFIG_SPE implementations are reserved so writing to
 882          * them does not change anything */
 883         if (val > PR_FP_EXC_PRECISE)
 884                 return -EINVAL;
 885         tsk->thread.fpexc_mode = __pack_fe01(val);
 886         if (regs != NULL && (regs->msr & MSR_FP) != 0)
 887                 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
 888                         | tsk->thread.fpexc_mode;
 889         return 0;
 890 }
 891
 892 int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
 893 {
 894         unsigned int val;
 895
 896         if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
 897 #ifdef CONFIG_SPE
 898                 if (cpu_has_feature(CPU_FTR_SPE))
 899                         val = tsk->thread.fpexc_mode;
 900                 else
 901                         return -EINVAL;
 902 #else
 903                 return -EINVAL;
 904 #endif
 905         else
 906                 val = __unpack_fe01(tsk->thread.fpexc_mode);
 907         return put_user(val, (unsigned int __user *) adr);
 908 }
 909
 910 int set_endian(struct task_struct *tsk, unsigned int val)
 911 {
 912         struct pt_regs *regs = tsk->thread.regs;
 913
 914         if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) ||
 915             (val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE)))
 916                 return -EINVAL;
 917
 918         if (regs == NULL)
 919                 return -EINVAL;
 920
 921         if (val == PR_ENDIAN_BIG)
 922                 regs->msr &= ~MSR_LE;
 923         else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE)
 924                 regs->msr |= MSR_LE;
 925         else
 926                 return -EINVAL;
 927
 928         return 0;
 929 }
 930
 931 int get_endian(struct task_struct *tsk, unsigned long adr)
 932 {
 933         struct pt_regs *regs = tsk->thread.regs;
 934         unsigned int val;
 935
 936         if (!cpu_has_feature(CPU_FTR_PPC_LE) &&
 937             !cpu_has_feature(CPU_FTR_REAL_LE))
 938                 return -EINVAL;
 939
 940         if (regs == NULL)
 941                 return -EINVAL;
 942
 943         if (regs->msr & MSR_LE) {
 944                 if (cpu_has_feature(CPU_FTR_REAL_LE))
 945                         val = PR_ENDIAN_LITTLE;
 946                 else
 947                         val = PR_ENDIAN_PPC_LITTLE;
 948         } else
 949                 val = PR_ENDIAN_BIG;
 950
 951         return put_user(val, (unsigned int __user *)adr);
 952 }
 953
 954 int set_unalign_ctl(struct task_struct *tsk, unsigned int val)
 955 {
 956         tsk->thread.align_ctl = val;
 957         return 0;
 958 }
 959
 960 int get_unalign_ctl(struct task_struct *tsk, unsigned long adr)
 961 {
 962         return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr);
 963 }
 964
 965 #define TRUNC_PTR(x)    ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
 966
 967 int sys_clone(unsigned long clone_flags, unsigned long usp,
 968               int __user *parent_tidp, void __user *child_threadptr,
 969               int __user *child_tidp, int p6,
 970               struct pt_regs *regs)
 971 {
 972         CHECK_FULL_REGS(regs);
 973         if (usp == 0)
 974                 usp = regs->gpr[1];     /* stack pointer for child */
 975 #ifdef CONFIG_PPC64
 976         if (test_thread_flag(TIF_32BIT)) {
 977                 parent_tidp = TRUNC_PTR(parent_tidp);
 978                 child_tidp = TRUNC_PTR(child_tidp);
 979         }
 980 #endif
 981         return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp);
 982 }
 983
 984 int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
 985              unsigned long p4, unsigned long p5, unsigned long p6,
 986              struct pt_regs *regs)
 987 {
 988         CHECK_FULL_REGS(regs);
 989         return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
 990 }
 991
 992 int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
 993               unsigned long p4, unsigned long p5, unsigned long p6,
 994               struct pt_regs *regs)
 995 {
 996         CHECK_FULL_REGS(regs);
 997         return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1],
 998                         regs, 0, NULL, NULL);
 999 }
1000
1001 int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
1002                unsigned long a3, unsigned long a4, unsigned long a5,
1003                struct pt_regs *regs)
1004 {
1005         int error;
1006         char *filename;
1007
1008         filename = getname((char __user *) a0);
1009         error = PTR_ERR(filename);
1010         if (IS_ERR(filename))
1011                 goto out;
1012         flush_fp_to_thread(current);
1013         flush_altivec_to_thread(current);
1014         flush_spe_to_thread(current);
1015         error = do_execve(filename, (char __user * __user *) a1,
1016                           (char __user * __user *) a2, regs);
1017         putname(filename);
1018 out:
1019         return error;
1020 }
1021
1022 static inline int valid_irq_stack(unsigned long sp, struct task_struct *p,
1023                                   unsigned long nbytes)
1024 {
1025         unsigned long stack_page;
1026         unsigned long cpu = task_cpu(p);
1027
1028         /*
1029          * Avoid crashing if the stack has overflowed and corrupted
1030          * task_cpu(p), which is in the thread_info struct.
1031          */
1032         if (cpu < NR_CPUS && cpu_possible(cpu)) {
1033                 stack_page = (unsigned long) hardirq_ctx[cpu];
1034                 if (sp >= stack_page + sizeof(struct thread_struct)
1035                     && sp <= stack_page + THREAD_SIZE - nbytes)
1036                         return 1;
1037
1038                 stack_page = (unsigned long) softirq_ctx[cpu];
1039                 if (sp >= stack_page + sizeof(struct thread_struct)
1040                     && sp <= stack_page + THREAD_SIZE - nbytes)
1041                         return 1;
1042         }
1043         return 0;
1044 }
1045
1046 int validate_sp(unsigned long sp, struct task_struct *p,
1047                        unsigned long nbytes)
1048 {
1049         unsigned long stack_page = (unsigned long)task_stack_page(p);
1050
1051         if (sp >= stack_page + sizeof(struct thread_struct)
1052             && sp <= stack_page + THREAD_SIZE - nbytes)
1053                 return 1;
1054
1055         return valid_irq_stack(sp, p, nbytes);
1056 }
1057
1058 EXPORT_SYMBOL(validate_sp);
1059
1060 unsigned long get_wchan(struct task_struct *p)
1061 {
1062         unsigned long ip, sp;
1063         int count = 0;
1064
1065         if (!p || p == current || p->state == TASK_RUNNING)
1066                 return 0;
1067
1068         sp = p->thread.ksp;
1069         if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
1070                 return 0;
1071
1072         do {
1073                 sp = *(unsigned long *)sp;
1074                 if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
1075                         return 0;
1076                 if (count > 0) {
1077                         ip = ((unsigned long *)sp)[STACK_FRAME_LR_SAVE];
1078                         if (!in_sched_functions(ip))
1079                                 return ip;
1080                 }
1081         } while (count++ < 16);
1082         return 0;
1083 }
1084
1085 static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
1086
1087 void show_stack(struct task_struct *tsk, unsigned long *stack)
1088 {
1089         unsigned long sp, ip, lr, newsp;
1090         int count = 0;
1091         int firstframe = 1;
1092 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1093         int curr_frame = current->curr_ret_stack;
1094         extern void return_to_handler(void);
1095         unsigned long rth = (unsigned long)return_to_handler;
1096         unsigned long mrth = -1;
1097 #ifdef CONFIG_PPC64
1098         extern void mod_return_to_handler(void);
1099         rth = *(unsigned long *)rth;
1100         mrth = (unsigned long)mod_return_to_handler;
1101         mrth = *(unsigned long *)mrth;
1102 #endif
1103 #endif
1104
1105         sp = (unsigned long) stack;
1106         if (tsk == NULL)
1107                 tsk = current;
1108         if (sp == 0) {
1109                 if (tsk == current)
1110                         asm("mr %0,1" : "=r" (sp));
1111                 else
1112                         sp = tsk->thread.ksp;
1113         }
1114
1115         lr = 0;
1116         printk("Call Trace:\n");
1117         do {
1118                 if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD))
1119                         return;
1120
1121                 stack = (unsigned long *) sp;
1122                 newsp = stack[0];
1123                 ip = stack[STACK_FRAME_LR_SAVE];
1124                 if (!firstframe || ip != lr) {
1125                         printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip);
1126 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1127                         if ((ip == rth || ip == mrth) && curr_frame >= 0) {
1128                                 printk(" (%pS)",
1129                                        (void *)current->ret_stack[curr_frame].ret);
1130                                 curr_frame--;
1131                         }
1132 #endif
1133                         if (firstframe)
1134                                 printk(" (unreliable)");
1135                         printk("\n");
1136                 }
1137                 firstframe = 0;
1138
1139                 /*
1140                  * See if this is an exception frame.
1141                  * We look for the "regshere" marker in the current frame.
1142                  */
1143                 if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE)
1144                     && stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) {
1145                         struct pt_regs *regs = (struct pt_regs *)
1146                                 (sp + STACK_FRAME_OVERHEAD);
1147                         lr = regs->link;
1148                         printk("--- Exception: %lx at %pS\n    LR = %pS\n",
1149                                regs->trap, (void *)regs->nip, (void *)lr);
1150                         firstframe = 1;
1151                 }
1152
1153                 sp = newsp;
1154         } while (count++ < kstack_depth_to_print);
1155 }
1156
1157 void dump_stack(void)
1158 {
1159         show_stack(current, NULL);
1160 }
1161 EXPORT_SYMBOL(dump_stack);
1162
1163 #ifdef CONFIG_PPC64
1164 void ppc64_runlatch_on(void)
1165 {
1166         unsigned long ctrl;
1167
1168         if (cpu_has_feature(CPU_FTR_CTRL) && !test_thread_flag(TIF_RUNLATCH)) {
1169                 HMT_medium();
1170
1171                 ctrl = mfspr(SPRN_CTRLF);
1172                 ctrl |= CTRL_RUNLATCH;
1173                 mtspr(SPRN_CTRLT, ctrl);
1174
1175                 set_thread_flag(TIF_RUNLATCH);
1176         }
1177 }
1178
1179 void ppc64_runlatch_off(void)
1180 {
1181         unsigned long ctrl;
1182
1183         if (cpu_has_feature(CPU_FTR_CTRL) && test_thread_flag(TIF_RUNLATCH)) {
1184                 HMT_medium();
1185
1186                 clear_thread_flag(TIF_RUNLATCH);
1187
1188                 ctrl = mfspr(SPRN_CTRLF);
1189                 ctrl &= ~CTRL_RUNLATCH;
1190                 mtspr(SPRN_CTRLT, ctrl);
1191         }
1192 }
1193 #endif
1194
1195 #if THREAD_SHIFT < PAGE_SHIFT
1196
1197 static struct kmem_cache *thread_info_cache;
1198
1199 struct thread_info *alloc_thread_info(struct task_struct *tsk)
1200 {
1201         struct thread_info *ti;
1202
1203         ti = kmem_cache_alloc(thread_info_cache, GFP_KERNEL);
1204         if (unlikely(ti == NULL))
1205                 return NULL;
1206 #ifdef CONFIG_DEBUG_STACK_USAGE
1207         memset(ti, 0, THREAD_SIZE);
1208 #endif
1209         return ti;
1210 }
1211
1212 void free_thread_info(struct thread_info *ti)
1213 {
1214         kmem_cache_free(thread_info_cache, ti);
1215 }
1216
1217 void thread_info_cache_init(void)
1218 {
1219         thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
1220                                               THREAD_SIZE, 0, NULL);
1221         BUG_ON(thread_info_cache == NULL);
1222 }
1223
1224 #endif /* THREAD_SHIFT < PAGE_SHIFT */
1225
1226 unsigned long arch_align_stack(unsigned long sp)
1227 {
1228         if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
1229                 sp -= get_random_int() & ~PAGE_MASK;
1230         return sp & ~0xf;
1231 }
1232
1233 static inline unsigned long brk_rnd(void)
1234 {
1235         unsigned long rnd = 0;
1236
1237         /* 8MB for 32bit, 1GB for 64bit */
1238         if (is_32bit_task())
1239                 rnd = (long)(get_random_int() % (1<<(23-PAGE_SHIFT)));
1240         else
1241                 rnd = (long)(get_random_int() % (1<<(30-PAGE_SHIFT)));
1242
1243         return rnd << PAGE_SHIFT;
1244 }
1245
1246 unsigned long arch_randomize_brk(struct mm_struct *mm)
1247 {
1248         unsigned long base = mm->brk;
1249         unsigned long ret;
1250
1251 #ifdef CONFIG_PPC_STD_MMU_64
1252         /*
1253          * If we are using 1TB segments and we are allowed to randomise
1254          * the heap, we can put it above 1TB so it is backed by a 1TB
1255          * segment. Otherwise the heap will be in the bottom 1TB
1256          * which always uses 256MB segments and this may result in a
1257          * performance penalty.
1258          */
1259         if (!is_32bit_task() && (mmu_highuser_ssize == MMU_SEGSIZE_1T))
1260                 base = max_t(unsigned long, mm->brk, 1UL << SID_SHIFT_1T);
1261 #endif
1262
1263         ret = PAGE_ALIGN(base + brk_rnd());
1264
1265         if (ret < mm->brk)
1266                 return mm->brk;
1267
1268         return ret;
1269 }
1270
1271 unsigned long randomize_et_dyn(unsigned long base)
1272 {
1273         unsigned long ret = PAGE_ALIGN(base + brk_rnd());
1274
1275         if (ret < base)
1276                 return base;
1277
1278         return ret;
1279 }