1 /* $Id: process.c,v 1.161 2002/01/23 11:27:32 davem Exp $ 2 * linux/arch/sparc/kernel/process.c 3 * 4 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) 5 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be) 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/module.h> 16 #include <linux/sched.h> 17 #include <linux/kernel.h> 18 #include <linux/kallsyms.h> 19 #include <linux/mm.h> 20 #include <linux/stddef.h> 21 #include <linux/ptrace.h> 22 #include <linux/slab.h> 23 #include <linux/user.h> 24 #include <linux/a.out.h> 25 #include <linux/config.h> 26 #include <linux/smp.h> 27 #include <linux/smp_lock.h> 28 #include <linux/reboot.h> 29 #include <linux/delay.h> 30 #include <linux/pm.h> 31 #include <linux/init.h> 32 33 #include <asm/auxio.h> 34 #include <asm/oplib.h> 35 #include <asm/uaccess.h> 36 #include <asm/system.h> 37 #include <asm/page.h> 38 #include <asm/pgalloc.h> 39 #include <asm/pgtable.h> 40 #include <asm/delay.h> 41 #include <asm/processor.h> 42 #include <asm/psr.h> 43 #include <asm/elf.h> 44 #include <asm/unistd.h> 45 46 /* 47 * Power management idle function 48 * Set in pm platform drivers (apc.c and pmc.c) 49 */ 50 void (*pm_idle)(void); 51 52 /* 53 * Power-off handler instantiation for pm.h compliance 54 * This is done via auxio, but could be used as a fallback 55 * handler when auxio is not present-- unused for now... 56 */ 57 void (*pm_power_off)(void); 58 59 /* 60 * sysctl - toggle power-off restriction for serial console 61 * systems in machine_power_off() 62 */ 63 int scons_pwroff = 1; 64 65 extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *); 66 67 struct task_struct *last_task_used_math = NULL; 68 struct thread_info *current_set[NR_CPUS]; 69 70 #ifndef CONFIG_SMP 71 72 #define SUN4C_FAULT_HIGH 100 73 74 /* 75 * the idle loop on a Sparc... ;) 76 */ 77 void cpu_idle(void) 78 { 79 /* endless idle loop with no priority at all */ 80 for (;;) { 81 if (ARCH_SUN4C_SUN4) { 82 static int count = HZ; 83 static unsigned long last_jiffies; 84 static unsigned long last_faults; 85 static unsigned long fps; 86 unsigned long now; 87 unsigned long faults; 88 89 extern unsigned long sun4c_kernel_faults; 90 extern void sun4c_grow_kernel_ring(void); 91 92 local_irq_disable(); 93 now = jiffies; 94 count -= (now - last_jiffies); 95 last_jiffies = now; 96 if (count < 0) { 97 count += HZ; 98 faults = sun4c_kernel_faults; 99 fps = (fps + (faults - last_faults)) >> 1; 100 last_faults = faults; 101 #if 0 102 printk("kernel faults / second = %ld\n", fps); 103 #endif 104 if (fps >= SUN4C_FAULT_HIGH) { 105 sun4c_grow_kernel_ring(); 106 } 107 } 108 local_irq_enable(); 109 } 110 111 if (pm_idle) { 112 while (!need_resched()) 113 (*pm_idle)(); 114 } else { 115 while (!need_resched()) 116 cpu_relax(); 117 } 118 preempt_enable_no_resched(); 119 schedule(); 120 preempt_disable(); 121 check_pgt_cache(); 122 } 123 } 124 125 #else 126 127 /* This is being executed in task 0 'user space'. */ 128 void cpu_idle(void) 129 { 130 set_thread_flag(TIF_POLLING_NRFLAG); 131 /* endless idle loop with no priority at all */ 132 while(1) { 133 while (!need_resched()) 134 cpu_relax(); 135 preempt_enable_no_resched(); 136 schedule(); 137 preempt_disable(); 138 check_pgt_cache(); 139 } 140 } 141 142 #endif 143 144 extern char reboot_command []; 145 146 extern void (*prom_palette)(int); 147 148 /* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */ 149 void machine_halt(void) 150 { 151 local_irq_enable(); 152 mdelay(8); 153 local_irq_disable(); 154 if (!serial_console && prom_palette) 155 prom_palette (1); 156 prom_halt(); 157 panic("Halt failed!"); 158 } 159 160 void machine_restart(char * cmd) 161 { 162 char *p; 163 164 local_irq_enable(); 165 mdelay(8); 166 local_irq_disable(); 167 168 p = strchr (reboot_command, '\n'); 169 if (p) *p = 0; 170 if (!serial_console && prom_palette) 171 prom_palette (1); 172 if (cmd) 173 prom_reboot(cmd); 174 if (*reboot_command) 175 prom_reboot(reboot_command); 176 prom_feval ("reset"); 177 panic("Reboot failed!"); 178 } 179 180 void machine_power_off(void) 181 { 182 #ifdef CONFIG_SUN_AUXIO 183 if (auxio_power_register && (!serial_console || scons_pwroff)) 184 *auxio_power_register |= AUXIO_POWER_OFF; 185 #endif 186 machine_halt(); 187 } 188 189 static DEFINE_SPINLOCK(sparc_backtrace_lock); 190 191 void __show_backtrace(unsigned long fp) 192 { 193 struct reg_window *rw; 194 unsigned long flags; 195 int cpu = smp_processor_id(); 196 197 spin_lock_irqsave(&sparc_backtrace_lock, flags); 198 199 rw = (struct reg_window *)fp; 200 while(rw && (((unsigned long) rw) >= PAGE_OFFSET) && 201 !(((unsigned long) rw) & 0x7)) { 202 printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] " 203 "FP[%08lx] CALLER[%08lx]: ", cpu, 204 rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3], 205 rw->ins[4], rw->ins[5], 206 rw->ins[6], 207 rw->ins[7]); 208 print_symbol("%s\n", rw->ins[7]); 209 rw = (struct reg_window *) rw->ins[6]; 210 } 211 spin_unlock_irqrestore(&sparc_backtrace_lock, flags); 212 } 213 214 #define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t") 215 #define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t") 216 #define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp)) 217 218 void show_backtrace(void) 219 { 220 unsigned long fp; 221 222 __SAVE; __SAVE; __SAVE; __SAVE; 223 __SAVE; __SAVE; __SAVE; __SAVE; 224 __RESTORE; __RESTORE; __RESTORE; __RESTORE; 225 __RESTORE; __RESTORE; __RESTORE; __RESTORE; 226 227 __GET_FP(fp); 228 229 __show_backtrace(fp); 230 } 231 232 #ifdef CONFIG_SMP 233 void smp_show_backtrace_all_cpus(void) 234 { 235 xc0((smpfunc_t) show_backtrace); 236 show_backtrace(); 237 } 238 #endif 239 240 #if 0 241 void show_stackframe(struct sparc_stackf *sf) 242 { 243 unsigned long size; 244 unsigned long *stk; 245 int i; 246 247 printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx " 248 "l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n", 249 sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3], 250 sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]); 251 printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx " 252 "i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n", 253 sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3], 254 sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc); 255 printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx " 256 "x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n", 257 (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1], 258 sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5], 259 sf->xxargs[0]); 260 size = ((unsigned long)sf->fp) - ((unsigned long)sf); 261 size -= STACKFRAME_SZ; 262 stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ); 263 i = 0; 264 do { 265 printk("s%d: %08lx\n", i++, *stk++); 266 } while ((size -= sizeof(unsigned long))); 267 } 268 #endif 269 270 void show_regs(struct pt_regs *r) 271 { 272 struct reg_window *rw = (struct reg_window *) r->u_regs[14]; 273 274 printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n", 275 r->psr, r->pc, r->npc, r->y, print_tainted()); 276 print_symbol("PC: <%s>\n", r->pc); 277 printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", 278 r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3], 279 r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]); 280 printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", 281 r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11], 282 r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]); 283 print_symbol("RPC: <%s>\n", r->u_regs[15]); 284 285 printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", 286 rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3], 287 rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]); 288 printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", 289 rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3], 290 rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]); 291 } 292 293 /* 294 * The show_stack is an external API which we do not use ourselves. 295 * The oops is printed in die_if_kernel. 296 */ 297 void show_stack(struct task_struct *tsk, unsigned long *_ksp) 298 { 299 unsigned long pc, fp; 300 unsigned long task_base; 301 struct reg_window *rw; 302 int count = 0; 303 304 if (tsk != NULL) 305 task_base = (unsigned long) tsk->thread_info; 306 else 307 task_base = (unsigned long) current_thread_info(); 308 309 fp = (unsigned long) _ksp; 310 do { 311 /* Bogus frame pointer? */ 312 if (fp < (task_base + sizeof(struct thread_info)) || 313 fp >= (task_base + (PAGE_SIZE << 1))) 314 break; 315 rw = (struct reg_window *) fp; 316 pc = rw->ins[7]; 317 printk("[%08lx : ", pc); 318 print_symbol("%s ] ", pc); 319 fp = rw->ins[6]; 320 } while (++count < 16); 321 printk("\n"); 322 } 323 324 void dump_stack(void) 325 { 326 unsigned long *ksp; 327 328 __asm__ __volatile__("mov %%fp, %0" 329 : "=r" (ksp)); 330 show_stack(current, ksp); 331 } 332 333 EXPORT_SYMBOL(dump_stack); 334 335 /* 336 * Note: sparc64 has a pretty intricated thread_saved_pc, check it out. 337 */ 338 unsigned long thread_saved_pc(struct task_struct *tsk) 339 { 340 return tsk->thread_info->kpc; 341 } 342 343 /* 344 * Free current thread data structures etc.. 345 */ 346 void exit_thread(void) 347 { 348 #ifndef CONFIG_SMP 349 if(last_task_used_math == current) { 350 #else 351 if(current_thread_info()->flags & _TIF_USEDFPU) { 352 #endif 353 /* Keep process from leaving FPU in a bogon state. */ 354 put_psr(get_psr() | PSR_EF); 355 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, 356 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); 357 #ifndef CONFIG_SMP 358 last_task_used_math = NULL; 359 #else 360 current_thread_info()->flags &= ~_TIF_USEDFPU; 361 #endif 362 } 363 } 364 365 void flush_thread(void) 366 { 367 current_thread_info()->w_saved = 0; 368 369 /* No new signal delivery by default */ 370 current->thread.new_signal = 0; 371 #ifndef CONFIG_SMP 372 if(last_task_used_math == current) { 373 #else 374 if(current_thread_info()->flags & _TIF_USEDFPU) { 375 #endif 376 /* Clean the fpu. */ 377 put_psr(get_psr() | PSR_EF); 378 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, 379 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); 380 #ifndef CONFIG_SMP 381 last_task_used_math = NULL; 382 #else 383 current_thread_info()->flags &= ~_TIF_USEDFPU; 384 #endif 385 } 386 387 /* Now, this task is no longer a kernel thread. */ 388 current->thread.current_ds = USER_DS; 389 if (current->thread.flags & SPARC_FLAG_KTHREAD) { 390 current->thread.flags &= ~SPARC_FLAG_KTHREAD; 391 392 /* We must fixup kregs as well. */ 393 /* XXX This was not fixed for ti for a while, worked. Unused? */ 394 current->thread.kregs = (struct pt_regs *) 395 ((char *)current->thread_info + (THREAD_SIZE - TRACEREG_SZ)); 396 } 397 } 398 399 static __inline__ struct sparc_stackf __user * 400 clone_stackframe(struct sparc_stackf __user *dst, 401 struct sparc_stackf __user *src) 402 { 403 unsigned long size, fp; 404 struct sparc_stackf *tmp; 405 struct sparc_stackf __user *sp; 406 407 if (get_user(tmp, &src->fp)) 408 return NULL; 409 410 fp = (unsigned long) tmp; 411 size = (fp - ((unsigned long) src)); 412 fp = (unsigned long) dst; 413 sp = (struct sparc_stackf __user *)(fp - size); 414 415 /* do_fork() grabs the parent semaphore, we must release it 416 * temporarily so we can build the child clone stack frame 417 * without deadlocking. 418 */ 419 if (__copy_user(sp, src, size)) 420 sp = NULL; 421 else if (put_user(fp, &sp->fp)) 422 sp = NULL; 423 424 return sp; 425 } 426 427 asmlinkage int sparc_do_fork(unsigned long clone_flags, 428 unsigned long stack_start, 429 struct pt_regs *regs, 430 unsigned long stack_size) 431 { 432 unsigned long parent_tid_ptr, child_tid_ptr; 433 434 parent_tid_ptr = regs->u_regs[UREG_I2]; 435 child_tid_ptr = regs->u_regs[UREG_I4]; 436 437 return do_fork(clone_flags, stack_start, 438 regs, stack_size, 439 (int __user *) parent_tid_ptr, 440 (int __user *) child_tid_ptr); 441 } 442 443 /* Copy a Sparc thread. The fork() return value conventions 444 * under SunOS are nothing short of bletcherous: 445 * Parent --> %o0 == childs pid, %o1 == 0 446 * Child --> %o0 == parents pid, %o1 == 1 447 * 448 * NOTE: We have a separate fork kpsr/kwim because 449 * the parent could change these values between 450 * sys_fork invocation and when we reach here 451 * if the parent should sleep while trying to 452 * allocate the task_struct and kernel stack in 453 * do_fork(). 454 * XXX See comment above sys_vfork in sparc64. todo. 455 */ 456 extern void ret_from_fork(void); 457 458 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, 459 unsigned long unused, 460 struct task_struct *p, struct pt_regs *regs) 461 { 462 struct thread_info *ti = p->thread_info; 463 struct pt_regs *childregs; 464 char *new_stack; 465 466 #ifndef CONFIG_SMP 467 if(last_task_used_math == current) { 468 #else 469 if(current_thread_info()->flags & _TIF_USEDFPU) { 470 #endif 471 put_psr(get_psr() | PSR_EF); 472 fpsave(&p->thread.float_regs[0], &p->thread.fsr, 473 &p->thread.fpqueue[0], &p->thread.fpqdepth); 474 #ifdef CONFIG_SMP 475 current_thread_info()->flags &= ~_TIF_USEDFPU; 476 #endif 477 } 478 479 /* 480 * p->thread_info new_stack childregs 481 * ! ! ! {if(PSR_PS) } 482 * V V (stk.fr.) V (pt_regs) { (stk.fr.) } 483 * +----- - - - - - ------+===========+============={+==========}+ 484 */ 485 new_stack = (char*)ti + THREAD_SIZE; 486 if (regs->psr & PSR_PS) 487 new_stack -= STACKFRAME_SZ; 488 new_stack -= STACKFRAME_SZ + TRACEREG_SZ; 489 memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ); 490 childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ); 491 492 /* 493 * A new process must start with interrupts closed in 2.5, 494 * because this is how Mingo's scheduler works (see schedule_tail 495 * and finish_arch_switch). If we do not do it, a timer interrupt hits 496 * before we unlock, attempts to re-take the rq->lock, and then we die. 497 * Thus, kpsr|=PSR_PIL. 498 */ 499 ti->ksp = (unsigned long) new_stack; 500 ti->kpc = (((unsigned long) ret_from_fork) - 0x8); 501 ti->kpsr = current->thread.fork_kpsr | PSR_PIL; 502 ti->kwim = current->thread.fork_kwim; 503 504 if(regs->psr & PSR_PS) { 505 extern struct pt_regs fake_swapper_regs; 506 507 p->thread.kregs = &fake_swapper_regs; 508 new_stack += STACKFRAME_SZ + TRACEREG_SZ; 509 childregs->u_regs[UREG_FP] = (unsigned long) new_stack; 510 p->thread.flags |= SPARC_FLAG_KTHREAD; 511 p->thread.current_ds = KERNEL_DS; 512 memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ); 513 childregs->u_regs[UREG_G6] = (unsigned long) ti; 514 } else { 515 p->thread.kregs = childregs; 516 childregs->u_regs[UREG_FP] = sp; 517 p->thread.flags &= ~SPARC_FLAG_KTHREAD; 518 p->thread.current_ds = USER_DS; 519 520 if (sp != regs->u_regs[UREG_FP]) { 521 struct sparc_stackf __user *childstack; 522 struct sparc_stackf __user *parentstack; 523 524 /* 525 * This is a clone() call with supplied user stack. 526 * Set some valid stack frames to give to the child. 527 */ 528 childstack = (struct sparc_stackf __user *) 529 (sp & ~0x7UL); 530 parentstack = (struct sparc_stackf __user *) 531 regs->u_regs[UREG_FP]; 532 533 #if 0 534 printk("clone: parent stack:\n"); 535 show_stackframe(parentstack); 536 #endif 537 538 childstack = clone_stackframe(childstack, parentstack); 539 if (!childstack) 540 return -EFAULT; 541 542 #if 0 543 printk("clone: child stack:\n"); 544 show_stackframe(childstack); 545 #endif 546 547 childregs->u_regs[UREG_FP] = (unsigned long)childstack; 548 } 549 } 550 551 #ifdef CONFIG_SMP 552 /* FPU must be disabled on SMP. */ 553 childregs->psr &= ~PSR_EF; 554 #endif 555 556 /* Set the return value for the child. */ 557 childregs->u_regs[UREG_I0] = current->pid; 558 childregs->u_regs[UREG_I1] = 1; 559 560 /* Set the return value for the parent. */ 561 regs->u_regs[UREG_I1] = 0; 562 563 if (clone_flags & CLONE_SETTLS) 564 childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3]; 565 566 return 0; 567 } 568 569 /* 570 * fill in the user structure for a core dump.. 571 */ 572 void dump_thread(struct pt_regs * regs, struct user * dump) 573 { 574 unsigned long first_stack_page; 575 576 dump->magic = SUNOS_CORE_MAGIC; 577 dump->len = sizeof(struct user); 578 dump->regs.psr = regs->psr; 579 dump->regs.pc = regs->pc; 580 dump->regs.npc = regs->npc; 581 dump->regs.y = regs->y; 582 /* fuck me plenty */ 583 memcpy(&dump->regs.regs[0], ®s->u_regs[1], (sizeof(unsigned long) * 15)); 584 dump->uexec = current->thread.core_exec; 585 dump->u_tsize = (((unsigned long) current->mm->end_code) - 586 ((unsigned long) current->mm->start_code)) & ~(PAGE_SIZE - 1); 587 dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))); 588 dump->u_dsize -= dump->u_tsize; 589 dump->u_dsize &= ~(PAGE_SIZE - 1); 590 first_stack_page = (regs->u_regs[UREG_FP] & ~(PAGE_SIZE - 1)); 591 dump->u_ssize = (TASK_SIZE - first_stack_page) & ~(PAGE_SIZE - 1); 592 memcpy(&dump->fpu.fpstatus.fregs.regs[0], ¤t->thread.float_regs[0], (sizeof(unsigned long) * 32)); 593 dump->fpu.fpstatus.fsr = current->thread.fsr; 594 dump->fpu.fpstatus.flags = dump->fpu.fpstatus.extra = 0; 595 dump->fpu.fpstatus.fpq_count = current->thread.fpqdepth; 596 memcpy(&dump->fpu.fpstatus.fpq[0], ¤t->thread.fpqueue[0], 597 ((sizeof(unsigned long) * 2) * 16)); 598 dump->sigcode = 0; 599 } 600 601 /* 602 * fill in the fpu structure for a core dump. 603 */ 604 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs) 605 { 606 if (used_math()) { 607 memset(fpregs, 0, sizeof(*fpregs)); 608 fpregs->pr_q_entrysize = 8; 609 return 1; 610 } 611 #ifdef CONFIG_SMP 612 if (current_thread_info()->flags & _TIF_USEDFPU) { 613 put_psr(get_psr() | PSR_EF); 614 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, 615 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); 616 if (regs != NULL) { 617 regs->psr &= ~(PSR_EF); 618 current_thread_info()->flags &= ~(_TIF_USEDFPU); 619 } 620 } 621 #else 622 if (current == last_task_used_math) { 623 put_psr(get_psr() | PSR_EF); 624 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, 625 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); 626 if (regs != NULL) { 627 regs->psr &= ~(PSR_EF); 628 last_task_used_math = NULL; 629 } 630 } 631 #endif 632 memcpy(&fpregs->pr_fr.pr_regs[0], 633 ¤t->thread.float_regs[0], 634 (sizeof(unsigned long) * 32)); 635 fpregs->pr_fsr = current->thread.fsr; 636 fpregs->pr_qcnt = current->thread.fpqdepth; 637 fpregs->pr_q_entrysize = 8; 638 fpregs->pr_en = 1; 639 if(fpregs->pr_qcnt != 0) { 640 memcpy(&fpregs->pr_q[0], 641 ¤t->thread.fpqueue[0], 642 sizeof(struct fpq) * fpregs->pr_qcnt); 643 } 644 /* Zero out the rest. */ 645 memset(&fpregs->pr_q[fpregs->pr_qcnt], 0, 646 sizeof(struct fpq) * (32 - fpregs->pr_qcnt)); 647 return 1; 648 } 649 650 /* 651 * sparc_execve() executes a new program after the asm stub has set 652 * things up for us. This should basically do what I want it to. 653 */ 654 asmlinkage int sparc_execve(struct pt_regs *regs) 655 { 656 int error, base = 0; 657 char *filename; 658 659 /* Check for indirect call. */ 660 if(regs->u_regs[UREG_G1] == 0) 661 base = 1; 662 663 filename = getname((char __user *)regs->u_regs[base + UREG_I0]); 664 error = PTR_ERR(filename); 665 if(IS_ERR(filename)) 666 goto out; 667 error = do_execve(filename, 668 (char __user * __user *)regs->u_regs[base + UREG_I1], 669 (char __user * __user *)regs->u_regs[base + UREG_I2], 670 regs); 671 putname(filename); 672 if (error == 0) { 673 task_lock(current); 674 current->ptrace &= ~PT_DTRACE; 675 task_unlock(current); 676 } 677 out: 678 return error; 679 } 680 681 /* 682 * This is the mechanism for creating a new kernel thread. 683 * 684 * NOTE! Only a kernel-only process(ie the swapper or direct descendants 685 * who haven't done an "execve()") should use this: it will work within 686 * a system call from a "real" process, but the process memory space will 687 * not be free'd until both the parent and the child have exited. 688 */ 689 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) 690 { 691 long retval; 692 693 __asm__ __volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */ 694 "mov %5, %%g3\n\t" /* and arg. */ 695 "mov %1, %%g1\n\t" 696 "mov %2, %%o0\n\t" /* Clone flags. */ 697 "mov 0, %%o1\n\t" /* usp arg == 0 */ 698 "t 0x10\n\t" /* Linux/Sparc clone(). */ 699 "cmp %%o1, 0\n\t" 700 "be 1f\n\t" /* The parent, just return. */ 701 " nop\n\t" /* Delay slot. */ 702 "jmpl %%g2, %%o7\n\t" /* Call the function. */ 703 " mov %%g3, %%o0\n\t" /* Get back the arg in delay. */ 704 "mov %3, %%g1\n\t" 705 "t 0x10\n\t" /* Linux/Sparc exit(). */ 706 /* Notreached by child. */ 707 "1: mov %%o0, %0\n\t" : 708 "=r" (retval) : 709 "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED), 710 "i" (__NR_exit), "r" (fn), "r" (arg) : 711 "g1", "g2", "g3", "o0", "o1", "memory", "cc"); 712 return retval; 713 } 714 715 unsigned long get_wchan(struct task_struct *task) 716 { 717 unsigned long pc, fp, bias = 0; 718 unsigned long task_base = (unsigned long) task; 719 unsigned long ret = 0; 720 struct reg_window *rw; 721 int count = 0; 722 723 if (!task || task == current || 724 task->state == TASK_RUNNING) 725 goto out; 726 727 fp = task->thread_info->ksp + bias; 728 do { 729 /* Bogus frame pointer? */ 730 if (fp < (task_base + sizeof(struct thread_info)) || 731 fp >= (task_base + (2 * PAGE_SIZE))) 732 break; 733 rw = (struct reg_window *) fp; 734 pc = rw->ins[7]; 735 if (!in_sched_functions(pc)) { 736 ret = pc; 737 goto out; 738 } 739 fp = rw->ins[6] + bias; 740 } while (++count < 16); 741 742 out: 743 return ret; 744 } 745 746