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 /* 71 * default_idle is new in 2.5. XXX Review, currently stolen from sparc64. 72 */ 73 void default_idle(void) 74 { 75 } 76 77 #ifndef CONFIG_SMP 78 79 #define SUN4C_FAULT_HIGH 100 80 81 /* 82 * the idle loop on a Sparc... ;) 83 */ 84 void cpu_idle(void) 85 { 86 /* endless idle loop with no priority at all */ 87 for (;;) { 88 if (ARCH_SUN4C_SUN4) { 89 static int count = HZ; 90 static unsigned long last_jiffies; 91 static unsigned long last_faults; 92 static unsigned long fps; 93 unsigned long now; 94 unsigned long faults; 95 unsigned long flags; 96 97 extern unsigned long sun4c_kernel_faults; 98 extern void sun4c_grow_kernel_ring(void); 99 100 local_irq_save(flags); 101 now = jiffies; 102 count -= (now - last_jiffies); 103 last_jiffies = now; 104 if (count < 0) { 105 count += HZ; 106 faults = sun4c_kernel_faults; 107 fps = (fps + (faults - last_faults)) >> 1; 108 last_faults = faults; 109 #if 0 110 printk("kernel faults / second = %ld\n", fps); 111 #endif 112 if (fps >= SUN4C_FAULT_HIGH) { 113 sun4c_grow_kernel_ring(); 114 } 115 } 116 local_irq_restore(flags); 117 } 118 119 while((!need_resched()) && pm_idle) { 120 (*pm_idle)(); 121 } 122 123 schedule(); 124 check_pgt_cache(); 125 } 126 } 127 128 #else 129 130 /* This is being executed in task 0 'user space'. */ 131 void cpu_idle(void) 132 { 133 /* endless idle loop with no priority at all */ 134 while(1) { 135 if(need_resched()) { 136 schedule(); 137 check_pgt_cache(); 138 } 139 barrier(); /* or else gcc optimizes... */ 140 } 141 } 142 143 #endif 144 145 extern char reboot_command []; 146 147 extern void (*prom_palette)(int); 148 149 /* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */ 150 void machine_halt(void) 151 { 152 local_irq_enable(); 153 mdelay(8); 154 local_irq_disable(); 155 if (!serial_console && prom_palette) 156 prom_palette (1); 157 prom_halt(); 158 panic("Halt failed!"); 159 } 160 161 EXPORT_SYMBOL(machine_halt); 162 163 void machine_restart(char * cmd) 164 { 165 char *p; 166 167 local_irq_enable(); 168 mdelay(8); 169 local_irq_disable(); 170 171 p = strchr (reboot_command, '\n'); 172 if (p) *p = 0; 173 if (!serial_console && prom_palette) 174 prom_palette (1); 175 if (cmd) 176 prom_reboot(cmd); 177 if (*reboot_command) 178 prom_reboot(reboot_command); 179 prom_feval ("reset"); 180 panic("Reboot failed!"); 181 } 182 183 EXPORT_SYMBOL(machine_restart); 184 185 void machine_power_off(void) 186 { 187 #ifdef CONFIG_SUN_AUXIO 188 if (auxio_power_register && (!serial_console || scons_pwroff)) 189 *auxio_power_register |= AUXIO_POWER_OFF; 190 #endif 191 machine_halt(); 192 } 193 194 EXPORT_SYMBOL(machine_power_off); 195 196 static DEFINE_SPINLOCK(sparc_backtrace_lock); 197 198 void __show_backtrace(unsigned long fp) 199 { 200 struct reg_window *rw; 201 unsigned long flags; 202 int cpu = smp_processor_id(); 203 204 spin_lock_irqsave(&sparc_backtrace_lock, flags); 205 206 rw = (struct reg_window *)fp; 207 while(rw && (((unsigned long) rw) >= PAGE_OFFSET) && 208 !(((unsigned long) rw) & 0x7)) { 209 printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] " 210 "FP[%08lx] CALLER[%08lx]: ", cpu, 211 rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3], 212 rw->ins[4], rw->ins[5], 213 rw->ins[6], 214 rw->ins[7]); 215 print_symbol("%s\n", rw->ins[7]); 216 rw = (struct reg_window *) rw->ins[6]; 217 } 218 spin_unlock_irqrestore(&sparc_backtrace_lock, flags); 219 } 220 221 #define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t") 222 #define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t") 223 #define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp)) 224 225 void show_backtrace(void) 226 { 227 unsigned long fp; 228 229 __SAVE; __SAVE; __SAVE; __SAVE; 230 __SAVE; __SAVE; __SAVE; __SAVE; 231 __RESTORE; __RESTORE; __RESTORE; __RESTORE; 232 __RESTORE; __RESTORE; __RESTORE; __RESTORE; 233 234 __GET_FP(fp); 235 236 __show_backtrace(fp); 237 } 238 239 #ifdef CONFIG_SMP 240 void smp_show_backtrace_all_cpus(void) 241 { 242 xc0((smpfunc_t) show_backtrace); 243 show_backtrace(); 244 } 245 #endif 246 247 #if 0 248 void show_stackframe(struct sparc_stackf *sf) 249 { 250 unsigned long size; 251 unsigned long *stk; 252 int i; 253 254 printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx " 255 "l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n", 256 sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3], 257 sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]); 258 printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx " 259 "i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n", 260 sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3], 261 sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc); 262 printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx " 263 "x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n", 264 (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1], 265 sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5], 266 sf->xxargs[0]); 267 size = ((unsigned long)sf->fp) - ((unsigned long)sf); 268 size -= STACKFRAME_SZ; 269 stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ); 270 i = 0; 271 do { 272 printk("s%d: %08lx\n", i++, *stk++); 273 } while ((size -= sizeof(unsigned long))); 274 } 275 #endif 276 277 void show_regs(struct pt_regs *r) 278 { 279 struct reg_window *rw = (struct reg_window *) r->u_regs[14]; 280 281 printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n", 282 r->psr, r->pc, r->npc, r->y, print_tainted()); 283 print_symbol("PC: <%s>\n", r->pc); 284 printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", 285 r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3], 286 r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]); 287 printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", 288 r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11], 289 r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]); 290 print_symbol("RPC: <%s>\n", r->u_regs[15]); 291 292 printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", 293 rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3], 294 rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]); 295 printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", 296 rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3], 297 rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]); 298 } 299 300 /* 301 * The show_stack is an external API which we do not use ourselves. 302 * The oops is printed in die_if_kernel. 303 */ 304 void show_stack(struct task_struct *tsk, unsigned long *_ksp) 305 { 306 unsigned long pc, fp; 307 unsigned long task_base; 308 struct reg_window *rw; 309 int count = 0; 310 311 if (tsk != NULL) 312 task_base = (unsigned long) tsk->thread_info; 313 else 314 task_base = (unsigned long) current_thread_info(); 315 316 fp = (unsigned long) _ksp; 317 do { 318 /* Bogus frame pointer? */ 319 if (fp < (task_base + sizeof(struct thread_info)) || 320 fp >= (task_base + (PAGE_SIZE << 1))) 321 break; 322 rw = (struct reg_window *) fp; 323 pc = rw->ins[7]; 324 printk("[%08lx : ", pc); 325 print_symbol("%s ] ", pc); 326 fp = rw->ins[6]; 327 } while (++count < 16); 328 printk("\n"); 329 } 330 331 void dump_stack(void) 332 { 333 unsigned long *ksp; 334 335 __asm__ __volatile__("mov %%fp, %0" 336 : "=r" (ksp)); 337 show_stack(current, ksp); 338 } 339 340 EXPORT_SYMBOL(dump_stack); 341 342 /* 343 * Note: sparc64 has a pretty intricated thread_saved_pc, check it out. 344 */ 345 unsigned long thread_saved_pc(struct task_struct *tsk) 346 { 347 return tsk->thread_info->kpc; 348 } 349 350 /* 351 * Free current thread data structures etc.. 352 */ 353 void exit_thread(void) 354 { 355 #ifndef CONFIG_SMP 356 if(last_task_used_math == current) { 357 #else 358 if(current_thread_info()->flags & _TIF_USEDFPU) { 359 #endif 360 /* Keep process from leaving FPU in a bogon state. */ 361 put_psr(get_psr() | PSR_EF); 362 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, 363 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); 364 #ifndef CONFIG_SMP 365 last_task_used_math = NULL; 366 #else 367 current_thread_info()->flags &= ~_TIF_USEDFPU; 368 #endif 369 } 370 } 371 372 void flush_thread(void) 373 { 374 current_thread_info()->w_saved = 0; 375 376 /* No new signal delivery by default */ 377 current->thread.new_signal = 0; 378 #ifndef CONFIG_SMP 379 if(last_task_used_math == current) { 380 #else 381 if(current_thread_info()->flags & _TIF_USEDFPU) { 382 #endif 383 /* Clean the fpu. */ 384 put_psr(get_psr() | PSR_EF); 385 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, 386 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); 387 #ifndef CONFIG_SMP 388 last_task_used_math = NULL; 389 #else 390 current_thread_info()->flags &= ~_TIF_USEDFPU; 391 #endif 392 } 393 394 /* Now, this task is no longer a kernel thread. */ 395 current->thread.current_ds = USER_DS; 396 if (current->thread.flags & SPARC_FLAG_KTHREAD) { 397 current->thread.flags &= ~SPARC_FLAG_KTHREAD; 398 399 /* We must fixup kregs as well. */ 400 /* XXX This was not fixed for ti for a while, worked. Unused? */ 401 current->thread.kregs = (struct pt_regs *) 402 ((char *)current->thread_info + (THREAD_SIZE - TRACEREG_SZ)); 403 } 404 } 405 406 static __inline__ struct sparc_stackf __user * 407 clone_stackframe(struct sparc_stackf __user *dst, 408 struct sparc_stackf __user *src) 409 { 410 unsigned long size, fp; 411 struct sparc_stackf *tmp; 412 struct sparc_stackf __user *sp; 413 414 if (get_user(tmp, &src->fp)) 415 return NULL; 416 417 fp = (unsigned long) tmp; 418 size = (fp - ((unsigned long) src)); 419 fp = (unsigned long) dst; 420 sp = (struct sparc_stackf __user *)(fp - size); 421 422 /* do_fork() grabs the parent semaphore, we must release it 423 * temporarily so we can build the child clone stack frame 424 * without deadlocking. 425 */ 426 if (__copy_user(sp, src, size)) 427 sp = NULL; 428 else if (put_user(fp, &sp->fp)) 429 sp = NULL; 430 431 return sp; 432 } 433 434 asmlinkage int sparc_do_fork(unsigned long clone_flags, 435 unsigned long stack_start, 436 struct pt_regs *regs, 437 unsigned long stack_size) 438 { 439 unsigned long parent_tid_ptr, child_tid_ptr; 440 441 parent_tid_ptr = regs->u_regs[UREG_I2]; 442 child_tid_ptr = regs->u_regs[UREG_I4]; 443 444 return do_fork(clone_flags, stack_start, 445 regs, stack_size, 446 (int __user *) parent_tid_ptr, 447 (int __user *) child_tid_ptr); 448 } 449 450 /* Copy a Sparc thread. The fork() return value conventions 451 * under SunOS are nothing short of bletcherous: 452 * Parent --> %o0 == childs pid, %o1 == 0 453 * Child --> %o0 == parents pid, %o1 == 1 454 * 455 * NOTE: We have a separate fork kpsr/kwim because 456 * the parent could change these values between 457 * sys_fork invocation and when we reach here 458 * if the parent should sleep while trying to 459 * allocate the task_struct and kernel stack in 460 * do_fork(). 461 * XXX See comment above sys_vfork in sparc64. todo. 462 */ 463 extern void ret_from_fork(void); 464 465 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, 466 unsigned long unused, 467 struct task_struct *p, struct pt_regs *regs) 468 { 469 struct thread_info *ti = p->thread_info; 470 struct pt_regs *childregs; 471 char *new_stack; 472 473 #ifndef CONFIG_SMP 474 if(last_task_used_math == current) { 475 #else 476 if(current_thread_info()->flags & _TIF_USEDFPU) { 477 #endif 478 put_psr(get_psr() | PSR_EF); 479 fpsave(&p->thread.float_regs[0], &p->thread.fsr, 480 &p->thread.fpqueue[0], &p->thread.fpqdepth); 481 #ifdef CONFIG_SMP 482 current_thread_info()->flags &= ~_TIF_USEDFPU; 483 #endif 484 } 485 486 /* 487 * p->thread_info new_stack childregs 488 * ! ! ! {if(PSR_PS) } 489 * V V (stk.fr.) V (pt_regs) { (stk.fr.) } 490 * +----- - - - - - ------+===========+============={+==========}+ 491 */ 492 new_stack = (char*)ti + THREAD_SIZE; 493 if (regs->psr & PSR_PS) 494 new_stack -= STACKFRAME_SZ; 495 new_stack -= STACKFRAME_SZ + TRACEREG_SZ; 496 memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ); 497 childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ); 498 499 /* 500 * A new process must start with interrupts closed in 2.5, 501 * because this is how Mingo's scheduler works (see schedule_tail 502 * and finish_arch_switch). If we do not do it, a timer interrupt hits 503 * before we unlock, attempts to re-take the rq->lock, and then we die. 504 * Thus, kpsr|=PSR_PIL. 505 */ 506 ti->ksp = (unsigned long) new_stack; 507 ti->kpc = (((unsigned long) ret_from_fork) - 0x8); 508 ti->kpsr = current->thread.fork_kpsr | PSR_PIL; 509 ti->kwim = current->thread.fork_kwim; 510 511 if(regs->psr & PSR_PS) { 512 extern struct pt_regs fake_swapper_regs; 513 514 p->thread.kregs = &fake_swapper_regs; 515 new_stack += STACKFRAME_SZ + TRACEREG_SZ; 516 childregs->u_regs[UREG_FP] = (unsigned long) new_stack; 517 p->thread.flags |= SPARC_FLAG_KTHREAD; 518 p->thread.current_ds = KERNEL_DS; 519 memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ); 520 childregs->u_regs[UREG_G6] = (unsigned long) ti; 521 } else { 522 p->thread.kregs = childregs; 523 childregs->u_regs[UREG_FP] = sp; 524 p->thread.flags &= ~SPARC_FLAG_KTHREAD; 525 p->thread.current_ds = USER_DS; 526 527 if (sp != regs->u_regs[UREG_FP]) { 528 struct sparc_stackf __user *childstack; 529 struct sparc_stackf __user *parentstack; 530 531 /* 532 * This is a clone() call with supplied user stack. 533 * Set some valid stack frames to give to the child. 534 */ 535 childstack = (struct sparc_stackf __user *) 536 (sp & ~0x7UL); 537 parentstack = (struct sparc_stackf __user *) 538 regs->u_regs[UREG_FP]; 539 540 #if 0 541 printk("clone: parent stack:\n"); 542 show_stackframe(parentstack); 543 #endif 544 545 childstack = clone_stackframe(childstack, parentstack); 546 if (!childstack) 547 return -EFAULT; 548 549 #if 0 550 printk("clone: child stack:\n"); 551 show_stackframe(childstack); 552 #endif 553 554 childregs->u_regs[UREG_FP] = (unsigned long)childstack; 555 } 556 } 557 558 #ifdef CONFIG_SMP 559 /* FPU must be disabled on SMP. */ 560 childregs->psr &= ~PSR_EF; 561 #endif 562 563 /* Set the return value for the child. */ 564 childregs->u_regs[UREG_I0] = current->pid; 565 childregs->u_regs[UREG_I1] = 1; 566 567 /* Set the return value for the parent. */ 568 regs->u_regs[UREG_I1] = 0; 569 570 if (clone_flags & CLONE_SETTLS) 571 childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3]; 572 573 return 0; 574 } 575 576 /* 577 * fill in the user structure for a core dump.. 578 */ 579 void dump_thread(struct pt_regs * regs, struct user * dump) 580 { 581 unsigned long first_stack_page; 582 583 dump->magic = SUNOS_CORE_MAGIC; 584 dump->len = sizeof(struct user); 585 dump->regs.psr = regs->psr; 586 dump->regs.pc = regs->pc; 587 dump->regs.npc = regs->npc; 588 dump->regs.y = regs->y; 589 /* fuck me plenty */ 590 memcpy(&dump->regs.regs[0], ®s->u_regs[1], (sizeof(unsigned long) * 15)); 591 dump->uexec = current->thread.core_exec; 592 dump->u_tsize = (((unsigned long) current->mm->end_code) - 593 ((unsigned long) current->mm->start_code)) & ~(PAGE_SIZE - 1); 594 dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))); 595 dump->u_dsize -= dump->u_tsize; 596 dump->u_dsize &= ~(PAGE_SIZE - 1); 597 first_stack_page = (regs->u_regs[UREG_FP] & ~(PAGE_SIZE - 1)); 598 dump->u_ssize = (TASK_SIZE - first_stack_page) & ~(PAGE_SIZE - 1); 599 memcpy(&dump->fpu.fpstatus.fregs.regs[0], ¤t->thread.float_regs[0], (sizeof(unsigned long) * 32)); 600 dump->fpu.fpstatus.fsr = current->thread.fsr; 601 dump->fpu.fpstatus.flags = dump->fpu.fpstatus.extra = 0; 602 dump->fpu.fpstatus.fpq_count = current->thread.fpqdepth; 603 memcpy(&dump->fpu.fpstatus.fpq[0], ¤t->thread.fpqueue[0], 604 ((sizeof(unsigned long) * 2) * 16)); 605 dump->sigcode = 0; 606 } 607 608 /* 609 * fill in the fpu structure for a core dump. 610 */ 611 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs) 612 { 613 if (used_math()) { 614 memset(fpregs, 0, sizeof(*fpregs)); 615 fpregs->pr_q_entrysize = 8; 616 return 1; 617 } 618 #ifdef CONFIG_SMP 619 if (current_thread_info()->flags & _TIF_USEDFPU) { 620 put_psr(get_psr() | PSR_EF); 621 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, 622 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); 623 if (regs != NULL) { 624 regs->psr &= ~(PSR_EF); 625 current_thread_info()->flags &= ~(_TIF_USEDFPU); 626 } 627 } 628 #else 629 if (current == last_task_used_math) { 630 put_psr(get_psr() | PSR_EF); 631 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, 632 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); 633 if (regs != NULL) { 634 regs->psr &= ~(PSR_EF); 635 last_task_used_math = NULL; 636 } 637 } 638 #endif 639 memcpy(&fpregs->pr_fr.pr_regs[0], 640 ¤t->thread.float_regs[0], 641 (sizeof(unsigned long) * 32)); 642 fpregs->pr_fsr = current->thread.fsr; 643 fpregs->pr_qcnt = current->thread.fpqdepth; 644 fpregs->pr_q_entrysize = 8; 645 fpregs->pr_en = 1; 646 if(fpregs->pr_qcnt != 0) { 647 memcpy(&fpregs->pr_q[0], 648 ¤t->thread.fpqueue[0], 649 sizeof(struct fpq) * fpregs->pr_qcnt); 650 } 651 /* Zero out the rest. */ 652 memset(&fpregs->pr_q[fpregs->pr_qcnt], 0, 653 sizeof(struct fpq) * (32 - fpregs->pr_qcnt)); 654 return 1; 655 } 656 657 /* 658 * sparc_execve() executes a new program after the asm stub has set 659 * things up for us. This should basically do what I want it to. 660 */ 661 asmlinkage int sparc_execve(struct pt_regs *regs) 662 { 663 int error, base = 0; 664 char *filename; 665 666 /* Check for indirect call. */ 667 if(regs->u_regs[UREG_G1] == 0) 668 base = 1; 669 670 filename = getname((char __user *)regs->u_regs[base + UREG_I0]); 671 error = PTR_ERR(filename); 672 if(IS_ERR(filename)) 673 goto out; 674 error = do_execve(filename, 675 (char __user * __user *)regs->u_regs[base + UREG_I1], 676 (char __user * __user *)regs->u_regs[base + UREG_I2], 677 regs); 678 putname(filename); 679 if (error == 0) { 680 task_lock(current); 681 current->ptrace &= ~PT_DTRACE; 682 task_unlock(current); 683 } 684 out: 685 return error; 686 } 687 688 /* 689 * This is the mechanism for creating a new kernel thread. 690 * 691 * NOTE! Only a kernel-only process(ie the swapper or direct descendants 692 * who haven't done an "execve()") should use this: it will work within 693 * a system call from a "real" process, but the process memory space will 694 * not be free'd until both the parent and the child have exited. 695 */ 696 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) 697 { 698 long retval; 699 700 __asm__ __volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */ 701 "mov %5, %%g3\n\t" /* and arg. */ 702 "mov %1, %%g1\n\t" 703 "mov %2, %%o0\n\t" /* Clone flags. */ 704 "mov 0, %%o1\n\t" /* usp arg == 0 */ 705 "t 0x10\n\t" /* Linux/Sparc clone(). */ 706 "cmp %%o1, 0\n\t" 707 "be 1f\n\t" /* The parent, just return. */ 708 " nop\n\t" /* Delay slot. */ 709 "jmpl %%g2, %%o7\n\t" /* Call the function. */ 710 " mov %%g3, %%o0\n\t" /* Get back the arg in delay. */ 711 "mov %3, %%g1\n\t" 712 "t 0x10\n\t" /* Linux/Sparc exit(). */ 713 /* Notreached by child. */ 714 "1: mov %%o0, %0\n\t" : 715 "=r" (retval) : 716 "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED), 717 "i" (__NR_exit), "r" (fn), "r" (arg) : 718 "g1", "g2", "g3", "o0", "o1", "memory", "cc"); 719 return retval; 720 } 721 722 unsigned long get_wchan(struct task_struct *task) 723 { 724 unsigned long pc, fp, bias = 0; 725 unsigned long task_base = (unsigned long) task; 726 unsigned long ret = 0; 727 struct reg_window *rw; 728 int count = 0; 729 730 if (!task || task == current || 731 task->state == TASK_RUNNING) 732 goto out; 733 734 fp = task->thread_info->ksp + bias; 735 do { 736 /* Bogus frame pointer? */ 737 if (fp < (task_base + sizeof(struct thread_info)) || 738 fp >= (task_base + (2 * PAGE_SIZE))) 739 break; 740 rw = (struct reg_window *) fp; 741 pc = rw->ins[7]; 742 if (!in_sched_functions(pc)) { 743 ret = pc; 744 goto out; 745 } 746 fp = rw->ins[6] + bias; 747 } while (++count < 16); 748 749 out: 750 return ret; 751 } 752 753