arch/sh64/kernel/process.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * arch/sh64/kernel/process.c
   7  *
   8  * Copyright (C) 2000, 2001  Paolo Alberelli
   9  * Copyright (C) 2003  Paul Mundt
  10  * Copyright (C) 2003, 2004 Richard Curnow
  11  *
  12  * Started from SH3/4 version:
  13  *   Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
  14  *
  15  *   In turn started from i386 version:
  16  *     Copyright (C) 1995  Linus Torvalds
  17  *
  18  */
  19
  20 /*
  21  * This file handles the architecture-dependent parts of process handling..
  22  */
  23 #include <linux/mm.h>
  24 #include <linux/fs.h>
  25 #include <linux/ptrace.h>
  26 #include <linux/reboot.h>
  27 #include <linux/init.h>
  28 #include <linux/module.h>
  29 #include <asm/uaccess.h>
  30 #include <asm/pgtable.h>
  31
  32 struct task_struct *last_task_used_math = NULL;
  33
  34 static int hlt_counter = 1;
  35
  36 #define HARD_IDLE_TIMEOUT (HZ / 3)
  37
  38 void disable_hlt(void)
  39 {
  40         hlt_counter++;
  41 }
  42
  43 void enable_hlt(void)
  44 {
  45         hlt_counter--;
  46 }
  47
  48 static int __init nohlt_setup(char *__unused)
  49 {
  50         hlt_counter = 1;
  51         return 1;
  52 }
  53
  54 static int __init hlt_setup(char *__unused)
  55 {
  56         hlt_counter = 0;
  57         return 1;
  58 }
  59
  60 __setup("nohlt", nohlt_setup);
  61 __setup("hlt", hlt_setup);
  62
  63 static inline void hlt(void)
  64 {
  65         __asm__ __volatile__ ("sleep" : : : "memory");
  66 }
  67
  68 /*
  69  * The idle loop on a uniprocessor SH..
  70  */
  71 void cpu_idle(void)
  72 {
  73         /* endless idle loop with no priority at all */
  74         while (1) {
  75                 if (hlt_counter) {
  76                         while (!need_resched())
  77                                 cpu_relax();
  78                 } else {
  79                         local_irq_disable();
  80                         while (!need_resched()) {
  81                                 local_irq_enable();
  82                                 hlt();
  83                                 local_irq_disable();
  84                         }
  85                         local_irq_enable();
  86                 }
  87                 preempt_enable_no_resched();
  88                 schedule();
  89                 preempt_disable();
  90         }
  91
  92 }
  93
  94 void machine_restart(char * __unused)
  95 {
  96         extern void phys_stext(void);
  97
  98         phys_stext();
  99 }
 100
 101 void machine_halt(void)
 102 {
 103         for (;;);
 104 }
 105
 106 void machine_power_off(void)
 107 {
 108         extern void enter_deep_standby(void);
 109
 110         enter_deep_standby();
 111 }
 112
 113 void (*pm_power_off)(void) = machine_power_off;
 114 EXPORT_SYMBOL(pm_power_off);
 115
 116 void show_regs(struct pt_regs * regs)
 117 {
 118         unsigned long long ah, al, bh, bl, ch, cl;
 119
 120         printk("\n");
 121
 122         ah = (regs->pc) >> 32;
 123         al = (regs->pc) & 0xffffffff;
 124         bh = (regs->regs[18]) >> 32;
 125         bl = (regs->regs[18]) & 0xffffffff;
 126         ch = (regs->regs[15]) >> 32;
 127         cl = (regs->regs[15]) & 0xffffffff;
 128         printk("PC  : %08Lx%08Lx LINK: %08Lx%08Lx SP  : %08Lx%08Lx\n",
 129                ah, al, bh, bl, ch, cl);
 130
 131         ah = (regs->sr) >> 32;
 132         al = (regs->sr) & 0xffffffff;
 133         asm volatile ("getcon   " __TEA ", %0" : "=r" (bh));
 134         asm volatile ("getcon   " __TEA ", %0" : "=r" (bl));
 135         bh = (bh) >> 32;
 136         bl = (bl) & 0xffffffff;
 137         asm volatile ("getcon   " __KCR0 ", %0" : "=r" (ch));
 138         asm volatile ("getcon   " __KCR0 ", %0" : "=r" (cl));
 139         ch = (ch) >> 32;
 140         cl = (cl) & 0xffffffff;
 141         printk("SR  : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
 142                ah, al, bh, bl, ch, cl);
 143
 144         ah = (regs->regs[0]) >> 32;
 145         al = (regs->regs[0]) & 0xffffffff;
 146         bh = (regs->regs[1]) >> 32;
 147         bl = (regs->regs[1]) & 0xffffffff;
 148         ch = (regs->regs[2]) >> 32;
 149         cl = (regs->regs[2]) & 0xffffffff;
 150         printk("R0  : %08Lx%08Lx R1  : %08Lx%08Lx R2  : %08Lx%08Lx\n",
 151                ah, al, bh, bl, ch, cl);
 152
 153         ah = (regs->regs[3]) >> 32;
 154         al = (regs->regs[3]) & 0xffffffff;
 155         bh = (regs->regs[4]) >> 32;
 156         bl = (regs->regs[4]) & 0xffffffff;
 157         ch = (regs->regs[5]) >> 32;
 158         cl = (regs->regs[5]) & 0xffffffff;
 159         printk("R3  : %08Lx%08Lx R4  : %08Lx%08Lx R5  : %08Lx%08Lx\n",
 160                ah, al, bh, bl, ch, cl);
 161
 162         ah = (regs->regs[6]) >> 32;
 163         al = (regs->regs[6]) & 0xffffffff;
 164         bh = (regs->regs[7]) >> 32;
 165         bl = (regs->regs[7]) & 0xffffffff;
 166         ch = (regs->regs[8]) >> 32;
 167         cl = (regs->regs[8]) & 0xffffffff;
 168         printk("R6  : %08Lx%08Lx R7  : %08Lx%08Lx R8  : %08Lx%08Lx\n",
 169                ah, al, bh, bl, ch, cl);
 170
 171         ah = (regs->regs[9]) >> 32;
 172         al = (regs->regs[9]) & 0xffffffff;
 173         bh = (regs->regs[10]) >> 32;
 174         bl = (regs->regs[10]) & 0xffffffff;
 175         ch = (regs->regs[11]) >> 32;
 176         cl = (regs->regs[11]) & 0xffffffff;
 177         printk("R9  : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
 178                ah, al, bh, bl, ch, cl);
 179
 180         ah = (regs->regs[12]) >> 32;
 181         al = (regs->regs[12]) & 0xffffffff;
 182         bh = (regs->regs[13]) >> 32;
 183         bl = (regs->regs[13]) & 0xffffffff;
 184         ch = (regs->regs[14]) >> 32;
 185         cl = (regs->regs[14]) & 0xffffffff;
 186         printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
 187                ah, al, bh, bl, ch, cl);
 188
 189         ah = (regs->regs[16]) >> 32;
 190         al = (regs->regs[16]) & 0xffffffff;
 191         bh = (regs->regs[17]) >> 32;
 192         bl = (regs->regs[17]) & 0xffffffff;
 193         ch = (regs->regs[19]) >> 32;
 194         cl = (regs->regs[19]) & 0xffffffff;
 195         printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
 196                ah, al, bh, bl, ch, cl);
 197
 198         ah = (regs->regs[20]) >> 32;
 199         al = (regs->regs[20]) & 0xffffffff;
 200         bh = (regs->regs[21]) >> 32;
 201         bl = (regs->regs[21]) & 0xffffffff;
 202         ch = (regs->regs[22]) >> 32;
 203         cl = (regs->regs[22]) & 0xffffffff;
 204         printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
 205                ah, al, bh, bl, ch, cl);
 206
 207         ah = (regs->regs[23]) >> 32;
 208         al = (regs->regs[23]) & 0xffffffff;
 209         bh = (regs->regs[24]) >> 32;
 210         bl = (regs->regs[24]) & 0xffffffff;
 211         ch = (regs->regs[25]) >> 32;
 212         cl = (regs->regs[25]) & 0xffffffff;
 213         printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
 214                ah, al, bh, bl, ch, cl);
 215
 216         ah = (regs->regs[26]) >> 32;
 217         al = (regs->regs[26]) & 0xffffffff;
 218         bh = (regs->regs[27]) >> 32;
 219         bl = (regs->regs[27]) & 0xffffffff;
 220         ch = (regs->regs[28]) >> 32;
 221         cl = (regs->regs[28]) & 0xffffffff;
 222         printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
 223                ah, al, bh, bl, ch, cl);
 224
 225         ah = (regs->regs[29]) >> 32;
 226         al = (regs->regs[29]) & 0xffffffff;
 227         bh = (regs->regs[30]) >> 32;
 228         bl = (regs->regs[30]) & 0xffffffff;
 229         ch = (regs->regs[31]) >> 32;
 230         cl = (regs->regs[31]) & 0xffffffff;
 231         printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
 232                ah, al, bh, bl, ch, cl);
 233
 234         ah = (regs->regs[32]) >> 32;
 235         al = (regs->regs[32]) & 0xffffffff;
 236         bh = (regs->regs[33]) >> 32;
 237         bl = (regs->regs[33]) & 0xffffffff;
 238         ch = (regs->regs[34]) >> 32;
 239         cl = (regs->regs[34]) & 0xffffffff;
 240         printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
 241                ah, al, bh, bl, ch, cl);
 242
 243         ah = (regs->regs[35]) >> 32;
 244         al = (regs->regs[35]) & 0xffffffff;
 245         bh = (regs->regs[36]) >> 32;
 246         bl = (regs->regs[36]) & 0xffffffff;
 247         ch = (regs->regs[37]) >> 32;
 248         cl = (regs->regs[37]) & 0xffffffff;
 249         printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
 250                ah, al, bh, bl, ch, cl);
 251
 252         ah = (regs->regs[38]) >> 32;
 253         al = (regs->regs[38]) & 0xffffffff;
 254         bh = (regs->regs[39]) >> 32;
 255         bl = (regs->regs[39]) & 0xffffffff;
 256         ch = (regs->regs[40]) >> 32;
 257         cl = (regs->regs[40]) & 0xffffffff;
 258         printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
 259                ah, al, bh, bl, ch, cl);
 260
 261         ah = (regs->regs[41]) >> 32;
 262         al = (regs->regs[41]) & 0xffffffff;
 263         bh = (regs->regs[42]) >> 32;
 264         bl = (regs->regs[42]) & 0xffffffff;
 265         ch = (regs->regs[43]) >> 32;
 266         cl = (regs->regs[43]) & 0xffffffff;
 267         printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
 268                ah, al, bh, bl, ch, cl);
 269
 270         ah = (regs->regs[44]) >> 32;
 271         al = (regs->regs[44]) & 0xffffffff;
 272         bh = (regs->regs[45]) >> 32;
 273         bl = (regs->regs[45]) & 0xffffffff;
 274         ch = (regs->regs[46]) >> 32;
 275         cl = (regs->regs[46]) & 0xffffffff;
 276         printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
 277                ah, al, bh, bl, ch, cl);
 278
 279         ah = (regs->regs[47]) >> 32;
 280         al = (regs->regs[47]) & 0xffffffff;
 281         bh = (regs->regs[48]) >> 32;
 282         bl = (regs->regs[48]) & 0xffffffff;
 283         ch = (regs->regs[49]) >> 32;
 284         cl = (regs->regs[49]) & 0xffffffff;
 285         printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
 286                ah, al, bh, bl, ch, cl);
 287
 288         ah = (regs->regs[50]) >> 32;
 289         al = (regs->regs[50]) & 0xffffffff;
 290         bh = (regs->regs[51]) >> 32;
 291         bl = (regs->regs[51]) & 0xffffffff;
 292         ch = (regs->regs[52]) >> 32;
 293         cl = (regs->regs[52]) & 0xffffffff;
 294         printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
 295                ah, al, bh, bl, ch, cl);
 296
 297         ah = (regs->regs[53]) >> 32;
 298         al = (regs->regs[53]) & 0xffffffff;
 299         bh = (regs->regs[54]) >> 32;
 300         bl = (regs->regs[54]) & 0xffffffff;
 301         ch = (regs->regs[55]) >> 32;
 302         cl = (regs->regs[55]) & 0xffffffff;
 303         printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
 304                ah, al, bh, bl, ch, cl);
 305
 306         ah = (regs->regs[56]) >> 32;
 307         al = (regs->regs[56]) & 0xffffffff;
 308         bh = (regs->regs[57]) >> 32;
 309         bl = (regs->regs[57]) & 0xffffffff;
 310         ch = (regs->regs[58]) >> 32;
 311         cl = (regs->regs[58]) & 0xffffffff;
 312         printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
 313                ah, al, bh, bl, ch, cl);
 314
 315         ah = (regs->regs[59]) >> 32;
 316         al = (regs->regs[59]) & 0xffffffff;
 317         bh = (regs->regs[60]) >> 32;
 318         bl = (regs->regs[60]) & 0xffffffff;
 319         ch = (regs->regs[61]) >> 32;
 320         cl = (regs->regs[61]) & 0xffffffff;
 321         printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
 322                ah, al, bh, bl, ch, cl);
 323
 324         ah = (regs->regs[62]) >> 32;
 325         al = (regs->regs[62]) & 0xffffffff;
 326         bh = (regs->tregs[0]) >> 32;
 327         bl = (regs->tregs[0]) & 0xffffffff;
 328         ch = (regs->tregs[1]) >> 32;
 329         cl = (regs->tregs[1]) & 0xffffffff;
 330         printk("R62 : %08Lx%08Lx T0  : %08Lx%08Lx T1  : %08Lx%08Lx\n",
 331                ah, al, bh, bl, ch, cl);
 332
 333         ah = (regs->tregs[2]) >> 32;
 334         al = (regs->tregs[2]) & 0xffffffff;
 335         bh = (regs->tregs[3]) >> 32;
 336         bl = (regs->tregs[3]) & 0xffffffff;
 337         ch = (regs->tregs[4]) >> 32;
 338         cl = (regs->tregs[4]) & 0xffffffff;
 339         printk("T2  : %08Lx%08Lx T3  : %08Lx%08Lx T4  : %08Lx%08Lx\n",
 340                ah, al, bh, bl, ch, cl);
 341
 342         ah = (regs->tregs[5]) >> 32;
 343         al = (regs->tregs[5]) & 0xffffffff;
 344         bh = (regs->tregs[6]) >> 32;
 345         bl = (regs->tregs[6]) & 0xffffffff;
 346         ch = (regs->tregs[7]) >> 32;
 347         cl = (regs->tregs[7]) & 0xffffffff;
 348         printk("T5  : %08Lx%08Lx T6  : %08Lx%08Lx T7  : %08Lx%08Lx\n",
 349                ah, al, bh, bl, ch, cl);
 350
 351         /*
 352          * If we're in kernel mode, dump the stack too..
 353          */
 354         if (!user_mode(regs)) {
 355                 void show_stack(struct task_struct *tsk, unsigned long *sp);
 356                 unsigned long sp = regs->regs[15] & 0xffffffff;
 357                 struct task_struct *tsk = get_current();
 358
 359                 tsk->thread.kregs = regs;
 360
 361                 show_stack(tsk, (unsigned long *)sp);
 362         }
 363 }
 364
 365 struct task_struct * alloc_task_struct(void)
 366 {
 367         /* Get task descriptor pages */
 368         return (struct task_struct *)
 369                 __get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE));
 370 }
 371
 372 void free_task_struct(struct task_struct *p)
 373 {
 374         free_pages((unsigned long) p, get_order(THREAD_SIZE));
 375 }
 376
 377 /*
 378  * Create a kernel thread
 379  */
 380 ATTRIB_NORET void kernel_thread_helper(void *arg, int (*fn)(void *))
 381 {
 382         do_exit(fn(arg));
 383 }
 384
 385 /*
 386  * This is the mechanism for creating a new kernel thread.
 387  *
 388  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 389  * who haven't done an "execve()") should use this: it will work within
 390  * a system call from a "real" process, but the process memory space will
 391  * not be freed until both the parent and the child have exited.
 392  */
 393 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 394 {
 395         struct pt_regs regs;
 396
 397         memset(&regs, 0, sizeof(regs));
 398         regs.regs[2] = (unsigned long)arg;
 399         regs.regs[3] = (unsigned long)fn;
 400
 401         regs.pc = (unsigned long)kernel_thread_helper;
 402         regs.sr = (1 << 30);
 403
 404         return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
 405                        &regs, 0, NULL, NULL);
 406 }
 407
 408 /*
 409  * Free current thread data structures etc..
 410  */
 411 void exit_thread(void)
 412 {
 413         /* See arch/sparc/kernel/process.c for the precedent for doing this -- RPC.
 414
 415            The SH-5 FPU save/restore approach relies on last_task_used_math
 416            pointing to a live task_struct.  When another task tries to use the
 417            FPU for the 1st time, the FPUDIS trap handling (see
 418            arch/sh64/kernel/fpu.c) will save the existing FPU state to the
 419            FP regs field within last_task_used_math before re-loading the new
 420            task's FPU state (or initialising it if the FPU has been used
 421            before).  So if last_task_used_math is stale, and its page has already been
 422            re-allocated for another use, the consequences are rather grim. Unless we
 423            null it here, there is no other path through which it would get safely
 424            nulled. */
 425
 426 #ifdef CONFIG_SH_FPU
 427         if (last_task_used_math == current) {
 428                 last_task_used_math = NULL;
 429         }
 430 #endif
 431 }
 432
 433 void flush_thread(void)
 434 {
 435
 436         /* Called by fs/exec.c (flush_old_exec) to remove traces of a
 437          * previously running executable. */
 438 #ifdef CONFIG_SH_FPU
 439         if (last_task_used_math == current) {
 440                 last_task_used_math = NULL;
 441         }
 442         /* Force FPU state to be reinitialised after exec */
 443         clear_used_math();
 444 #endif
 445
 446         /* if we are a kernel thread, about to change to user thread,
 447          * update kreg
 448          */
 449         if(current->thread.kregs==&fake_swapper_regs) {
 450           current->thread.kregs =
 451              ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
 452           current->thread.uregs = current->thread.kregs;
 453         }
 454 }
 455
 456 void release_thread(struct task_struct *dead_task)
 457 {
 458         /* do nothing */
 459 }
 460
 461 /* Fill in the fpu structure for a core dump.. */
 462 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
 463 {
 464 #ifdef CONFIG_SH_FPU
 465         int fpvalid;
 466         struct task_struct *tsk = current;
 467
 468         fpvalid = !!tsk_used_math(tsk);
 469         if (fpvalid) {
 470                 if (current == last_task_used_math) {
 471                         grab_fpu();
 472                         fpsave(&tsk->thread.fpu.hard);
 473                         release_fpu();
 474                         last_task_used_math = 0;
 475                         regs->sr |= SR_FD;
 476                 }
 477
 478                 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
 479         }
 480
 481         return fpvalid;
 482 #else
 483         return 0; /* Task didn't use the fpu at all. */
 484 #endif
 485 }
 486
 487 asmlinkage void ret_from_fork(void);
 488
 489 int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
 490                 unsigned long unused,
 491                 struct task_struct *p, struct pt_regs *regs)
 492 {
 493         struct pt_regs *childregs;
 494         unsigned long long se;                  /* Sign extension */
 495
 496 #ifdef CONFIG_SH_FPU
 497         if(last_task_used_math == current) {
 498                 grab_fpu();
 499                 fpsave(&current->thread.fpu.hard);
 500                 release_fpu();
 501                 last_task_used_math = NULL;
 502                 regs->sr |= SR_FD;
 503         }
 504 #endif
 505         /* Copy from sh version */
 506         childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;
 507
 508         *childregs = *regs;
 509
 510         if (user_mode(regs)) {
 511                 childregs->regs[15] = usp;
 512                 p->thread.uregs = childregs;
 513         } else {
 514                 childregs->regs[15] = (unsigned long)task_stack_page(p) + THREAD_SIZE;
 515         }
 516
 517         childregs->regs[9] = 0; /* Set return value for child */
 518         childregs->sr |= SR_FD; /* Invalidate FPU flag */
 519
 520         p->thread.sp = (unsigned long) childregs;
 521         p->thread.pc = (unsigned long) ret_from_fork;
 522
 523         /*
 524          * Sign extend the edited stack.
 525          * Note that thread.pc and thread.pc will stay
 526          * 32-bit wide and context switch must take care
 527          * of NEFF sign extension.
 528          */
 529
 530         se = childregs->regs[15];
 531         se = (se & NEFF_SIGN) ? (se | NEFF_MASK) : se;
 532         childregs->regs[15] = se;
 533
 534         return 0;
 535 }
 536
 537 asmlinkage int sys_fork(unsigned long r2, unsigned long r3,
 538                         unsigned long r4, unsigned long r5,
 539                         unsigned long r6, unsigned long r7,
 540                         struct pt_regs *pregs)
 541 {
 542         return do_fork(SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
 543 }
 544
 545 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
 546                          unsigned long r4, unsigned long r5,
 547                          unsigned long r6, unsigned long r7,
 548                          struct pt_regs *pregs)
 549 {
 550         if (!newsp)
 551                 newsp = pregs->regs[15];
 552         return do_fork(clone_flags, newsp, pregs, 0, 0, 0);
 553 }
 554
 555 /*
 556  * This is trivial, and on the face of it looks like it
 557  * could equally well be done in user mode.
 558  *
 559  * Not so, for quite unobvious reasons - register pressure.
 560  * In user mode vfork() cannot have a stack frame, and if
 561  * done by calling the "clone()" system call directly, you
 562  * do not have enough call-clobbered registers to hold all
 563  * the information you need.
 564  */
 565 asmlinkage int sys_vfork(unsigned long r2, unsigned long r3,
 566                          unsigned long r4, unsigned long r5,
 567                          unsigned long r6, unsigned long r7,
 568                          struct pt_regs *pregs)
 569 {
 570         return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
 571 }
 572
 573 /*
 574  * sys_execve() executes a new program.
 575  */
 576 asmlinkage int sys_execve(char *ufilename, char **uargv,
 577                           char **uenvp, unsigned long r5,
 578                           unsigned long r6, unsigned long r7,
 579                           struct pt_regs *pregs)
 580 {
 581         int error;
 582         char *filename;
 583
 584         lock_kernel();
 585         filename = getname((char __user *)ufilename);
 586         error = PTR_ERR(filename);
 587         if (IS_ERR(filename))
 588                 goto out;
 589
 590         error = do_execve(filename,
 591                           (char __user * __user *)uargv,
 592                           (char __user * __user *)uenvp,
 593                           pregs);
 594         if (error == 0) {
 595                 task_lock(current);
 596                 current->ptrace &= ~PT_DTRACE;
 597                 task_unlock(current);
 598         }
 599         putname(filename);
 600 out:
 601         unlock_kernel();
 602         return error;
 603 }
 604
 605 /*
 606  * These bracket the sleeping functions..
 607  */
 608 extern void interruptible_sleep_on(wait_queue_head_t *q);
 609
 610 #define mid_sched       ((unsigned long) interruptible_sleep_on)
 611
 612 static int in_sh64_switch_to(unsigned long pc)
 613 {
 614         extern char __sh64_switch_to_end;
 615         /* For a sleeping task, the PC is somewhere in the middle of the function,
 616            so we don't have to worry about masking the LSB off */
 617         return (pc >= (unsigned long) sh64_switch_to) &&
 618                (pc < (unsigned long) &__sh64_switch_to_end);
 619 }
 620
 621 unsigned long get_wchan(struct task_struct *p)
 622 {
 623         unsigned long schedule_fp;
 624         unsigned long sh64_switch_to_fp;
 625         unsigned long schedule_caller_pc;
 626         unsigned long pc;
 627
 628         if (!p || p == current || p->state == TASK_RUNNING)
 629                 return 0;
 630
 631         /*
 632          * The same comment as on the Alpha applies here, too ...
 633          */
 634         pc = thread_saved_pc(p);
 635
 636 #ifdef CONFIG_FRAME_POINTER
 637         if (in_sh64_switch_to(pc)) {
 638                 sh64_switch_to_fp = (long) p->thread.sp;
 639                 /* r14 is saved at offset 4 in the sh64_switch_to frame */
 640                 schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);
 641
 642                 /* and the caller of 'schedule' is (currently!) saved at offset 24
 643                    in the frame of schedule (from disasm) */
 644                 schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
 645                 return schedule_caller_pc;
 646         }
 647 #endif
 648         return pc;
 649 }
 650
 651 /* Provide a /proc/asids file that lists out the
 652    ASIDs currently associated with the processes.  (If the DM.PC register is
 653    examined through the debug link, this shows ASID + PC.  To make use of this,
 654    the PID->ASID relationship needs to be known.  This is primarily for
 655    debugging.)
 656    */
 657
 658 #if defined(CONFIG_SH64_PROC_ASIDS)
 659 #include <linux/init.h>
 660 #include <linux/proc_fs.h>
 661
 662 static int
 663 asids_proc_info(char *buf, char **start, off_t fpos, int length, int *eof, void *data)
 664 {
 665         int len=0;
 666         struct task_struct *p;
 667         read_lock(&tasklist_lock);
 668         for_each_process(p) {
 669                 int pid = p->pid;
 670                 struct mm_struct *mm;
 671                 if (!pid) continue;
 672                 mm = p->mm;
 673                 if (mm) {
 674                         unsigned long asid, context;
 675                         context = mm->context;
 676                         asid = (context & 0xff);
 677                         len += sprintf(buf+len, "%5d : %02lx\n", pid, asid);
 678                 } else {
 679                         len += sprintf(buf+len, "%5d : (none)\n", pid);
 680                 }
 681         }
 682         read_unlock(&tasklist_lock);
 683         *eof = 1;
 684         return len;
 685 }
 686
 687 static int __init register_proc_asids(void)
 688 {
 689   create_proc_read_entry("asids", 0, NULL, asids_proc_info, NULL);
 690   return 0;
 691 }
 692
 693 __initcall(register_proc_asids);
 694 #endif
 695