trap.c revision 1.14
1/* $NetBSD: trap.c,v 1.14 2003/07/15 02:54:44 lukem Exp $ */ 2 3/* 4 * Copyright 2001 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38/* 39 * Copyright (C) 1995, 1996 Wolfgang Solfrank. 40 * Copyright (C) 1995, 1996 TooLs GmbH. 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by TooLs GmbH. 54 * 4. The name of TooLs GmbH may not be used to endorse or promote products 55 * derived from this software without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 58 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 59 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 60 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 61 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 62 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 63 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 64 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 65 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 66 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69#include <sys/cdefs.h> 70__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.14 2003/07/15 02:54:44 lukem Exp $"); 71 72#include "opt_altivec.h" 73#include "opt_ddb.h" 74#include "opt_ktrace.h" 75#include "opt_systrace.h" 76#include "opt_syscall_debug.h" 77 78#include <sys/param.h> 79#include <sys/proc.h> 80#include <sys/reboot.h> 81#include <sys/syscall.h> 82#include <sys/systm.h> 83#include <sys/user.h> 84#ifdef KTRACE 85#include <sys/ktrace.h> 86#endif 87#include <sys/pool.h> 88#include <sys/sa.h> 89#include <sys/savar.h> 90#ifdef SYSTRACE 91#include <sys/systrace.h> 92#endif 93 94#include <uvm/uvm_extern.h> 95 96#include <dev/cons.h> 97 98#include <machine/cpu.h> 99#include <machine/db_machdep.h> 100#include <machine/fpu.h> 101#include <machine/frame.h> 102#include <machine/pcb.h> 103#include <machine/psl.h> 104#include <machine/trap.h> 105 106#include <powerpc/spr.h> 107#include <powerpc/ibm4xx/pmap.h> 108#include <powerpc/ibm4xx/tlb.h> 109#include <powerpc/fpu/fpu_extern.h> 110 111/* These definitions should probably be somewhere else XXX */ 112#define FIRSTARG 3 /* first argument is in reg 3 */ 113#define NARGREG 8 /* 8 args are in registers */ 114#define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */ 115 116static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); 117 118void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 119/* Why are these not defined in a header? */ 120int badaddr __P((void *, size_t)); 121int badaddr_read __P((void *, size_t, int *)); 122int ctx_setup __P((int, int)); 123 124#ifdef DEBUG 125#define TDB_ALL 0x1 126int trapdebug = /* TDB_ALL */ 0; 127#define DBPRINTF(x, y) if (trapdebug & (x)) printf y 128#else 129#define DBPRINTF(x, y) 130#endif 131 132void 133trap(struct trapframe *frame) 134{ 135 struct lwp *l = curlwp; 136 struct proc *p = l ? l->l_proc : NULL; 137 int type = frame->exc; 138 int ftype, rv; 139 140 KASSERT(l == 0 || (l->l_stat == LSONPROC)); 141 142 if (frame->srr1 & PSL_PR) 143 type |= EXC_USER; 144 145 ftype = VM_PROT_READ; 146 147 DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n", 148 type, frame->srr0, frame, &frame)); 149 150 switch (type) { 151 case EXC_DEBUG|EXC_USER: 152 { 153 int srr2, srr3; 154 155 __asm __volatile("mfspr %0,0x3f0" : 156 "=r" (rv), "=r" (srr2), "=r" (srr3) :); 157 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, 158 srr3); 159 /* XXX fall through or break here?! */ 160 } 161 /* 162 * DEBUG intr -- probably single-step. 163 */ 164 case EXC_TRC|EXC_USER: 165 KERNEL_PROC_LOCK(l); 166 frame->srr1 &= ~PSL_SE; 167 trapsignal(l, SIGTRAP, EXC_TRC); 168 KERNEL_PROC_UNLOCK(l); 169 break; 170 171 /* 172 * If we could not find and install appropriate TLB entry, fall through. 173 */ 174 175 case EXC_DSI: 176 /* FALLTHROUGH */ 177 case EXC_DTMISS: 178 { 179 struct vm_map *map; 180 vaddr_t va; 181 struct faultbuf *fb = NULL; 182 183 KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE); 184 va = frame->dar; 185 if (frame->tf_xtra[TF_PID] == KERNEL_PID) { 186 map = kernel_map; 187 } else { 188 map = &p->p_vmspace->vm_map; 189 } 190 191 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 192 ftype = VM_PROT_WRITE; 193 194 DBPRINTF(TDB_ALL, 195 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 196 frame->srr0, 197 (ftype & VM_PROT_WRITE) ? "write" : "read", 198 (void *)va, frame->tf_xtra[TF_ESR])); 199 rv = uvm_fault(map, trunc_page(va), 0, ftype); 200 KERNEL_UNLOCK(); 201 if (rv == 0) 202 goto done; 203 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 204 frame->tf_xtra[TF_PID] = KERNEL_PID; 205 frame->srr0 = fb->fb_pc; 206 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 207 frame->fixreg[1] = fb->fb_sp; 208 frame->fixreg[2] = fb->fb_r2; 209 frame->fixreg[3] = 1; /* Return TRUE */ 210 frame->cr = fb->fb_cr; 211 memcpy(&frame->fixreg[13], fb->fb_fixreg, 212 sizeof(fb->fb_fixreg)); 213 goto done; 214 } 215 } 216 goto brain_damage; 217 218 case EXC_DSI|EXC_USER: 219 /* FALLTHROUGH */ 220 case EXC_DTMISS|EXC_USER: 221 KERNEL_PROC_LOCK(l); 222 223 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 224 ftype = VM_PROT_WRITE; 225 226 DBPRINTF(TDB_ALL, 227 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 228 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 229 frame->dar, frame->tf_xtra[TF_ESR])); 230 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 231 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar), 232 0, ftype); 233 if (rv == 0) { 234 KERNEL_PROC_UNLOCK(l); 235 break; 236 } 237 if (rv == ENOMEM) { 238 printf("UVM: pid %d (%s) lid %d, uid %d killed: " 239 "out of swap\n", 240 p->p_pid, p->p_comm, l->l_lid, 241 p->p_cred && p->p_ucred ? 242 p->p_ucred->cr_uid : -1); 243 trapsignal(l, SIGKILL, EXC_DSI); 244 } else { 245 trapsignal(l, SIGSEGV, EXC_DSI); 246 } 247 KERNEL_PROC_UNLOCK(l); 248 break; 249 case EXC_ITMISS|EXC_USER: 250 case EXC_ISI|EXC_USER: 251 KERNEL_PROC_LOCK(l); 252 ftype = VM_PROT_READ | VM_PROT_EXECUTE; 253 DBPRINTF(TDB_ALL, 254 ("trap(EXC_ISI|EXC_USER) at %lx %s fault on %lx tf %p\n", 255 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 256 frame->srr0, frame)); 257 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 258 0, ftype); 259 if (rv == 0) { 260 KERNEL_PROC_UNLOCK(l); 261 break; 262 } 263 trapsignal(l, SIGSEGV, EXC_ISI); 264 KERNEL_PROC_UNLOCK(l); 265 break; 266 267 case EXC_AST|EXC_USER: 268 curcpu()->ci_astpending = 0; /* we are about to do it */ 269 KERNEL_PROC_LOCK(l); 270 uvmexp.softs++; 271 if (p->p_flag & P_OWEUPC) { 272 p->p_flag &= ~P_OWEUPC; 273 ADDUPROF(p); 274 } 275 /* Check whether we are being preempted. */ 276 if (curcpu()->ci_want_resched) 277 preempt(0); 278 KERNEL_PROC_UNLOCK(l); 279 break; 280 281 282 case EXC_ALI|EXC_USER: 283 KERNEL_PROC_LOCK(l); 284 if (fix_unaligned(l, frame) != 0) 285 trapsignal(l, SIGBUS, EXC_ALI); 286 else 287 frame->srr0 += 4; 288 KERNEL_PROC_UNLOCK(l); 289 break; 290 291 case EXC_PGM|EXC_USER: 292 /* 293 * Illegal insn: 294 * 295 * let's try to see if it's FPU and can be emulated. 296 */ 297 uvmexp.traps ++; 298 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { 299 memset(&l->l_addr->u_pcb.pcb_fpu, 0, 300 sizeof l->l_addr->u_pcb.pcb_fpu); 301 l->l_addr->u_pcb.pcb_flags |= PCB_FPU; 302 } 303 304 if ((rv = fpu_emulate(frame, 305 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { 306 KERNEL_PROC_LOCK(l); 307 trapsignal(l, rv, EXC_PGM); 308 KERNEL_PROC_UNLOCK(l); 309 } 310 break; 311 312 case EXC_MCHK: 313 { 314 struct faultbuf *fb; 315 316 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 317 frame->tf_xtra[TF_PID] = KERNEL_PID; 318 frame->srr0 = fb->fb_pc; 319 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 320 frame->fixreg[1] = fb->fb_sp; 321 frame->fixreg[2] = fb->fb_r2; 322 frame->fixreg[3] = 1; /* Return TRUE */ 323 frame->cr = fb->fb_cr; 324 memcpy(&frame->fixreg[13], fb->fb_fixreg, 325 sizeof(fb->fb_fixreg)); 326 goto done; 327 } 328 } 329 goto brain_damage; 330 default: 331 brain_damage: 332 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); 333#ifdef DDB 334 if (kdb_trap(type, frame)) 335 goto done; 336#endif 337#ifdef TRAP_PANICWAIT 338 printf("Press a key to panic.\n"); 339 cngetc(); 340#endif 341 panic("trap"); 342 } 343 344 /* Take pending signals. */ 345 { 346 int sig; 347 348 while ((sig = CURSIG(l)) != 0) 349 postsig(sig); 350 } 351 352 /* Invoke per-process kernel-exit handling, if any */ 353 if (p->p_userret) 354 (p->p_userret)(l, p->p_userret_arg); 355 356 /* Invoke any pending upcalls */ 357 while (l->l_flag & L_SA_UPCALL) 358 sa_upcall_userret(l); 359 360 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 361 done: 362 return; 363} 364 365int 366ctx_setup(int ctx, int srr1) 367{ 368 volatile struct pmap *pm; 369 370 /* Update PID if we're returning to user mode. */ 371 if (srr1 & PSL_PR) { 372 pm = curproc->p_vmspace->vm_map.pmap; 373 if (!pm->pm_ctx) { 374 ctx_alloc((struct pmap *)pm); 375 } 376 ctx = pm->pm_ctx; 377 if (srr1 & PSL_SE) { 378 int dbreg, mask = 0x48000000; 379 /* 380 * Set the Internal Debug and 381 * Instruction Completion bits of 382 * the DBCR0 register. 383 * 384 * XXX this is also used by jtag debuggers... 385 */ 386 __asm __volatile("mfspr %0,0x3f2;" 387 "or %0,%0,%1;" 388 "mtspr 0x3f2,%0;" : 389 "=&r" (dbreg) : "r" (mask)); 390 } 391 } 392 else if (!ctx) { 393 ctx = KERNEL_PID; 394 } 395 return (ctx); 396} 397 398/* 399 * Used by copyin()/copyout() 400 */ 401extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 402extern void vunmaprange __P((vaddr_t, vsize_t)); 403static int bigcopyin __P((const void *, void *, size_t )); 404static int bigcopyout __P((const void *, void *, size_t )); 405 406int 407copyin(const void *udaddr, void *kaddr, size_t len) 408{ 409 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 410 int msr, pid, tmp, ctx; 411 struct faultbuf env; 412 413 /* For bigger buffers use the faster copy */ 414 if (len > 256) return (bigcopyin(udaddr, kaddr, len)); 415 416 if (setfault(&env)) { 417 curpcb->pcb_onfault = 0; 418 return EFAULT; 419 } 420 421 if (!(ctx = pm->pm_ctx)) { 422 /* No context -- assign it one */ 423 ctx_alloc(pm); 424 ctx = pm->pm_ctx; 425 } 426 427 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 428 "mfmsr %0;" /* Save MSR */ 429 "li %1,0x20; " 430 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 431 "mfpid %1;" /* Save old PID */ 432 "sync; isync;" 433 434 "1: bdz 2f;" /* while len */ 435 "mtpid %3; sync;" /* Load user ctx */ 436 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 437 "sync; isync;" 438 "mtpid %1;sync;" 439 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 440 "sync; isync;" 441 "b 1b;" /* repeat */ 442 443 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 444 "sync; isync;" 445 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 446 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 447 448 curpcb->pcb_onfault = 0; 449 return 0; 450} 451 452static int 453bigcopyin(const void *udaddr, void *kaddr, size_t len) 454{ 455 const char *up; 456 char *kp = kaddr; 457 struct lwp *l = curlwp; 458 struct proc *p; 459 int error; 460 461 if (!l) { 462 return EFAULT; 463 } 464 465 p = l->l_proc; 466 467 /* 468 * Stolen from physio(): 469 */ 470 PHOLD(l); 471 error = uvm_vslock(p, (caddr_t)udaddr, len, VM_PROT_READ); 472 if (error) { 473 PRELE(l); 474 return EFAULT; 475 } 476 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 477 478 memcpy(kp, up, len); 479 vunmaprange((vaddr_t)up, len); 480 uvm_vsunlock(p, (caddr_t)udaddr, len); 481 PRELE(l); 482 483 return 0; 484} 485 486int 487copyout(const void *kaddr, void *udaddr, size_t len) 488{ 489 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 490 int msr, pid, tmp, ctx; 491 struct faultbuf env; 492 493 /* For big copies use more efficient routine */ 494 if (len > 256) return (bigcopyout(kaddr, udaddr, len)); 495 496 if (setfault(&env)) { 497 curpcb->pcb_onfault = 0; 498 return EFAULT; 499 } 500 501 if (!(ctx = pm->pm_ctx)) { 502 /* No context -- assign it one */ 503 ctx_alloc(pm); 504 ctx = pm->pm_ctx; 505 } 506 507 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 508 "mfmsr %0;" /* Save MSR */ 509 "li %1,0x20; " 510 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 511 "mfpid %1;" /* Save old PID */ 512 "sync; isync;" 513 514 "1: bdz 2f;" /* while len */ 515 "mtpid %1;sync;" 516 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 517 "sync; isync;" 518 "mtpid %3; sync;" /* Load user ctx */ 519 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 520 "sync; isync;" 521 "b 1b;" /* repeat */ 522 523 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 524 "sync; isync;" 525 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 526 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 527 528 curpcb->pcb_onfault = 0; 529 return 0; 530} 531 532static int 533bigcopyout(const void *kaddr, void *udaddr, size_t len) 534{ 535 char *up; 536 const char *kp = (char *)kaddr; 537 struct lwp *l = curlwp; 538 struct proc *p; 539 int error; 540 541 if (!l) { 542 return EFAULT; 543 } 544 545 p = l->l_proc; 546 547 /* 548 * Stolen from physio(): 549 */ 550 PHOLD(l); 551 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE); 552 if (error) { 553 PRELE(l); 554 return EFAULT; 555 } 556 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 557 VM_PROT_READ | VM_PROT_WRITE); 558 559 memcpy(up, kp, len); 560 vunmaprange((vaddr_t)up, len); 561 uvm_vsunlock(p, udaddr, len); 562 PRELE(l); 563 564 return 0; 565} 566 567/* 568 * kcopy(const void *src, void *dst, size_t len); 569 * 570 * Copy len bytes from src to dst, aborting if we encounter a fatal 571 * page fault. 572 * 573 * kcopy() _must_ save and restore the old fault handler since it is 574 * called by uiomove(), which may be in the path of servicing a non-fatal 575 * page fault. 576 */ 577int 578kcopy(const void *src, void *dst, size_t len) 579{ 580 struct faultbuf env, *oldfault; 581 582 oldfault = curpcb->pcb_onfault; 583 if (setfault(&env)) { 584 curpcb->pcb_onfault = oldfault; 585 return EFAULT; 586 } 587 588 memcpy(dst, src, len); 589 590 curpcb->pcb_onfault = oldfault; 591 return 0; 592} 593 594int 595badaddr(void *addr, size_t size) 596{ 597 598 return badaddr_read(addr, size, NULL); 599} 600 601int 602badaddr_read(void *addr, size_t size, int *rptr) 603{ 604 struct faultbuf env; 605 int x; 606 607 /* Get rid of any stale machine checks that have been waiting. */ 608 __asm __volatile ("sync; isync"); 609 610 if (setfault(&env)) { 611 curpcb->pcb_onfault = 0; 612 __asm __volatile ("sync"); 613 return 1; 614 } 615 616 __asm __volatile ("sync"); 617 618 switch (size) { 619 case 1: 620 x = *(volatile int8_t *)addr; 621 break; 622 case 2: 623 x = *(volatile int16_t *)addr; 624 break; 625 case 4: 626 x = *(volatile int32_t *)addr; 627 break; 628 default: 629 panic("badaddr: invalid size (%d)", size); 630 } 631 632 /* Make sure we took the machine check, if we caused one. */ 633 __asm __volatile ("sync; isync"); 634 635 curpcb->pcb_onfault = 0; 636 __asm __volatile ("sync"); /* To be sure. */ 637 638 /* Use the value to avoid reorder. */ 639 if (rptr) 640 *rptr = x; 641 642 return 0; 643} 644 645/* 646 * For now, this only deals with the particular unaligned access case 647 * that gcc tends to generate. Eventually it should handle all of the 648 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 649 */ 650 651static int 652fix_unaligned(struct lwp *l, struct trapframe *frame) 653{ 654 655 return -1; 656} 657 658/* 659 * Start a new LWP 660 */ 661void 662startlwp(arg) 663 void *arg; 664{ 665 int err; 666 ucontext_t *uc = arg; 667 struct lwp *l = curlwp; 668 669 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 670#if DIAGNOSTIC 671 if (err) { 672 printf("Error %d from cpu_setmcontext.", err); 673 } 674#endif 675 pool_put(&lwp_uc_pool, uc); 676 677 upcallret(l); 678} 679 680/* 681 * XXX This is a terrible name. 682 */ 683void 684upcallret(l) 685 struct lwp *l; 686{ 687 int sig; 688 689 /* Take pending signals. */ 690 while ((sig = CURSIG(l)) != 0) 691 postsig(sig); 692 693 /* Invoke per-process kernel-exit handling, if any */ 694 if (l->l_proc->p_userret) 695 (l->l_proc->p_userret)(l, l->l_proc->p_userret_arg); 696 697 /* Invoke any pending upcalls */ 698 while (l->l_flag & L_SA_UPCALL) 699 sa_upcall_userret(l); 700 701 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 702} 703