1 /* 2 * (MPSAFE) 3 * 4 * Copyright (c) 2006 The DragonFly Project. All rights reserved. 5 * 6 * This code is derived from software contributed to The DragonFly Project 7 * by Matthew Dillon <dillon@backplane.com> 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 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 3. Neither the name of The DragonFly Project nor the names of its 20 * contributors may be used to endorse or promote products derived 21 * from this software without specific, prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 27 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 28 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 29 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 30 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 31 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/param.h> 38 #include <sys/kernel.h> 39 #include <sys/systm.h> 40 #include <sys/sysproto.h> 41 #include <sys/kern_syscall.h> 42 #include <sys/mman.h> 43 #include <sys/thread.h> 44 #include <sys/proc.h> 45 #include <sys/malloc.h> 46 #include <sys/sysctl.h> 47 #include <sys/vkernel.h> 48 #include <sys/vmspace.h> 49 50 #include <vm/vm_extern.h> 51 #include <vm/pmap.h> 52 53 #include <machine/vmparam.h> 54 #include <machine/vmm.h> 55 56 #include <sys/sysref2.h> 57 58 static struct vmspace_entry *vkernel_find_vmspace(struct vkernel_proc *vkp, 59 void *id); 60 static void vmspace_entry_delete(struct vmspace_entry *ve, 61 struct vkernel_proc *vkp); 62 63 static MALLOC_DEFINE(M_VKERNEL, "vkernel", "VKernel structures"); 64 65 /* 66 * vmspace_create (void *id, int type, void *data) 67 * 68 * Create a VMSPACE under the control of the caller with the specified id. 69 * An id of NULL cannot be used. The type and data fields must currently 70 * be 0. 71 * 72 * The vmspace starts out completely empty. Memory may be mapped into the 73 * VMSPACE with vmspace_mmap() and MAP_VPAGETABLE section(s) controlled 74 * with vmspace_mcontrol(). 75 * 76 * No requirements. 77 */ 78 int 79 sys_vmspace_create(struct vmspace_create_args *uap) 80 { 81 struct vmspace_entry *ve; 82 struct vkernel_proc *vkp; 83 struct proc *p = curproc; 84 int error; 85 86 if (vkernel_enable == 0) 87 return (EOPNOTSUPP); 88 89 /* 90 * Create a virtual kernel side-structure for the process if one 91 * does not exist. 92 * 93 * Implement a simple resolution for SMP races. 94 */ 95 if ((vkp = p->p_vkernel) == NULL) { 96 vkp = kmalloc(sizeof(*vkp), M_VKERNEL, M_WAITOK|M_ZERO); 97 lwkt_gettoken(&p->p_token); 98 if (p->p_vkernel == NULL) { 99 vkp->refs = 1; 100 lwkt_token_init(&vkp->token, "vkernel"); 101 RB_INIT(&vkp->root); 102 p->p_vkernel = vkp; 103 } else { 104 kfree(vkp, M_VKERNEL); 105 vkp = p->p_vkernel; 106 } 107 lwkt_reltoken(&p->p_token); 108 } 109 110 if (curthread->td_vmm) 111 return 0; 112 113 /* 114 * Create a new VMSPACE, disallow conflicting ids 115 */ 116 ve = kmalloc(sizeof(struct vmspace_entry), M_VKERNEL, M_WAITOK|M_ZERO); 117 ve->vmspace = vmspace_alloc(VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS); 118 ve->id = uap->id; 119 pmap_pinit2(vmspace_pmap(ve->vmspace)); 120 121 lwkt_gettoken(&vkp->token); 122 if (RB_INSERT(vmspace_rb_tree, &vkp->root, ve)) { 123 vmspace_free(ve->vmspace); 124 ve->vmspace = NULL; /* safety */ 125 kfree(ve, M_VKERNEL); 126 error = EEXIST; 127 } else { 128 error = 0; 129 } 130 lwkt_reltoken(&vkp->token); 131 132 return (error); 133 } 134 135 /* 136 * Destroy a VMSPACE given its identifier. 137 * 138 * No requirements. 139 */ 140 int 141 sys_vmspace_destroy(struct vmspace_destroy_args *uap) 142 { 143 struct vkernel_proc *vkp; 144 struct vmspace_entry *ve; 145 int error; 146 147 if ((vkp = curproc->p_vkernel) == NULL) { 148 error = EINVAL; 149 goto done3; 150 } 151 lwkt_gettoken(&vkp->token); 152 if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { 153 error = ENOENT; 154 goto done2; 155 } 156 if (ve->refs) { 157 error = EBUSY; 158 goto done2; 159 } 160 vmspace_entry_delete(ve, vkp); 161 error = 0; 162 done2: 163 lwkt_reltoken(&vkp->token); 164 done3: 165 return(error); 166 } 167 168 /* 169 * vmspace_ctl (void *id, int cmd, struct trapframe *tframe, 170 * struct vextframe *vframe); 171 * 172 * Transfer control to a VMSPACE. Control is returned after the specified 173 * number of microseconds or if a page fault, signal, trap, or system call 174 * occurs. The context is updated as appropriate. 175 * 176 * No requirements. 177 */ 178 int 179 sys_vmspace_ctl(struct vmspace_ctl_args *uap) 180 { 181 struct vkernel_proc *vkp; 182 struct vkernel_lwp *vklp; 183 struct vmspace_entry *ve = NULL; 184 struct lwp *lp; 185 struct proc *p; 186 int framesz; 187 int error; 188 189 lp = curthread->td_lwp; 190 p = lp->lwp_proc; 191 192 if ((vkp = p->p_vkernel) == NULL) 193 return (EINVAL); 194 195 /* 196 * ve only matters when VMM is not used. 197 */ 198 if (curthread->td_vmm == NULL) { 199 lwkt_gettoken(&vkp->token); 200 if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { 201 error = ENOENT; 202 goto done; 203 } 204 } 205 206 switch(uap->cmd) { 207 case VMSPACE_CTL_RUN: 208 /* 209 * Save the caller's register context, swap VM spaces, and 210 * install the passed register context. Return with 211 * EJUSTRETURN so the syscall code doesn't adjust the context. 212 */ 213 if (curthread->td_vmm == NULL) 214 atomic_add_int(&ve->refs, 1); 215 216 framesz = sizeof(struct trapframe); 217 if ((vklp = lp->lwp_vkernel) == NULL) { 218 vklp = kmalloc(sizeof(*vklp), M_VKERNEL, 219 M_WAITOK|M_ZERO); 220 lp->lwp_vkernel = vklp; 221 } 222 vklp->user_trapframe = uap->tframe; 223 vklp->user_vextframe = uap->vframe; 224 bcopy(uap->sysmsg_frame, &vklp->save_trapframe, framesz); 225 bcopy(&curthread->td_tls, &vklp->save_vextframe.vx_tls, 226 sizeof(vklp->save_vextframe.vx_tls)); 227 error = copyin(uap->tframe, uap->sysmsg_frame, framesz); 228 if (error == 0) { 229 error = copyin(&uap->vframe->vx_tls, 230 &curthread->td_tls, 231 sizeof(struct savetls)); 232 } 233 if (error == 0) 234 error = cpu_sanitize_frame(uap->sysmsg_frame); 235 if (error == 0) 236 error = cpu_sanitize_tls(&curthread->td_tls); 237 if (error) { 238 bcopy(&vklp->save_trapframe, uap->sysmsg_frame, 239 framesz); 240 bcopy(&vklp->save_vextframe.vx_tls, &curthread->td_tls, 241 sizeof(vklp->save_vextframe.vx_tls)); 242 set_user_TLS(); 243 if (curthread->td_vmm == NULL) 244 atomic_subtract_int(&ve->refs, 1); 245 } else { 246 /* If it's a VMM thread just set the CR3. We also set the 247 * vklp->ve to a key to be able to distinguish when a 248 * vkernel user process runs and when not (when it's NULL) 249 */ 250 if (curthread->td_vmm == NULL) { 251 vklp->ve = ve; 252 pmap_setlwpvm(lp, ve->vmspace); 253 } else { 254 vklp->ve = uap->id; 255 vmm_vm_set_guest_cr3((register_t)uap->id); 256 } 257 set_user_TLS(); 258 set_vkernel_fp(uap->sysmsg_frame); 259 error = EJUSTRETURN; 260 } 261 break; 262 default: 263 error = EOPNOTSUPP; 264 break; 265 } 266 done: 267 if (curthread->td_vmm == NULL) 268 lwkt_reltoken(&vkp->token); 269 return(error); 270 } 271 272 /* 273 * vmspace_mmap(id, addr, len, prot, flags, fd, offset) 274 * 275 * map memory within a VMSPACE. This function is just like a normal mmap() 276 * but operates on the vmspace's memory map. Most callers use this to create 277 * a MAP_VPAGETABLE mapping. 278 * 279 * No requirements. 280 */ 281 int 282 sys_vmspace_mmap(struct vmspace_mmap_args *uap) 283 { 284 struct vkernel_proc *vkp; 285 struct vmspace_entry *ve; 286 int error; 287 288 /* 289 * We hold the vmspace token to serialize calls to vkernel_find_vmspace. 290 */ 291 lwkt_gettoken(&vmspace_token); 292 if ((vkp = curproc->p_vkernel) == NULL) { 293 error = EINVAL; 294 goto done3; 295 } 296 297 /* 298 * NOTE: kern_mmap() can block so we need to temporarily ref ve->refs. 299 */ 300 lwkt_gettoken(&vkp->token); 301 if ((ve = vkernel_find_vmspace(vkp, uap->id)) != NULL) { 302 atomic_add_int(&ve->refs, 1); 303 error = kern_mmap(ve->vmspace, uap->addr, uap->len, 304 uap->prot, uap->flags, 305 uap->fd, uap->offset, &uap->sysmsg_resultp); 306 atomic_subtract_int(&ve->refs, 1); 307 } else { 308 error = ENOENT; 309 } 310 lwkt_reltoken(&vkp->token); 311 done3: 312 lwkt_reltoken(&vmspace_token); 313 return (error); 314 } 315 316 /* 317 * vmspace_munmap(id, addr, len) 318 * 319 * unmap memory within a VMSPACE. 320 * 321 * No requirements. 322 */ 323 int 324 sys_vmspace_munmap(struct vmspace_munmap_args *uap) 325 { 326 struct vkernel_proc *vkp; 327 struct vmspace_entry *ve; 328 vm_offset_t addr; 329 vm_offset_t tmpaddr; 330 vm_size_t size, pageoff; 331 vm_map_t map; 332 int error; 333 334 if ((vkp = curproc->p_vkernel) == NULL) { 335 error = EINVAL; 336 goto done3; 337 } 338 lwkt_gettoken(&vkp->token); 339 if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { 340 error = ENOENT; 341 goto done2; 342 } 343 344 /* 345 * NOTE: kern_munmap() can block so we need to temporarily 346 * ref ve->refs. 347 */ 348 atomic_add_int(&ve->refs, 1); 349 350 /* 351 * Copied from sys_munmap() 352 */ 353 addr = (vm_offset_t)uap->addr; 354 size = uap->len; 355 356 pageoff = (addr & PAGE_MASK); 357 addr -= pageoff; 358 size += pageoff; 359 size = (vm_size_t)round_page(size); 360 if (size < uap->len) { /* wrap */ 361 error = EINVAL; 362 goto done1; 363 } 364 tmpaddr = addr + size; /* workaround gcc4 opt */ 365 if (tmpaddr < addr) { /* wrap */ 366 error = EINVAL; 367 goto done1; 368 } 369 if (size == 0) { 370 error = 0; 371 goto done1; 372 } 373 374 if (VM_MAX_USER_ADDRESS > 0 && tmpaddr > VM_MAX_USER_ADDRESS) { 375 error = EINVAL; 376 goto done1; 377 } 378 if (VM_MIN_USER_ADDRESS > 0 && addr < VM_MIN_USER_ADDRESS) { 379 error = EINVAL; 380 goto done1; 381 } 382 map = &ve->vmspace->vm_map; 383 if (!vm_map_check_protection(map, addr, tmpaddr, VM_PROT_NONE, FALSE)) { 384 error = EINVAL; 385 goto done1; 386 } 387 vm_map_remove(map, addr, addr + size); 388 error = 0; 389 done1: 390 atomic_subtract_int(&ve->refs, 1); 391 done2: 392 lwkt_reltoken(&vkp->token); 393 done3: 394 return (error); 395 } 396 397 /* 398 * vmspace_pread(id, buf, nbyte, flags, offset) 399 * 400 * Read data from a vmspace. The number of bytes read is returned or 401 * -1 if an unrecoverable error occured. If the number of bytes read is 402 * less then the request size, a page fault occured in the VMSPACE which 403 * the caller must resolve in order to proceed. 404 * 405 * (not implemented yet) 406 * No requirements. 407 */ 408 int 409 sys_vmspace_pread(struct vmspace_pread_args *uap) 410 { 411 struct vkernel_proc *vkp; 412 struct vmspace_entry *ve; 413 int error; 414 415 if ((vkp = curproc->p_vkernel) == NULL) { 416 error = EINVAL; 417 goto done3; 418 } 419 lwkt_gettoken(&vkp->token); 420 if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { 421 error = ENOENT; 422 goto done2; 423 } 424 error = EINVAL; 425 done2: 426 lwkt_reltoken(&vkp->token); 427 done3: 428 return (error); 429 } 430 431 /* 432 * vmspace_pwrite(id, buf, nbyte, flags, offset) 433 * 434 * Write data to a vmspace. The number of bytes written is returned or 435 * -1 if an unrecoverable error occured. If the number of bytes written is 436 * less then the request size, a page fault occured in the VMSPACE which 437 * the caller must resolve in order to proceed. 438 * 439 * (not implemented yet) 440 * No requirements. 441 */ 442 int 443 sys_vmspace_pwrite(struct vmspace_pwrite_args *uap) 444 { 445 struct vkernel_proc *vkp; 446 struct vmspace_entry *ve; 447 int error; 448 449 if ((vkp = curproc->p_vkernel) == NULL) { 450 error = EINVAL; 451 goto done3; 452 } 453 lwkt_gettoken(&vkp->token); 454 if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { 455 error = ENOENT; 456 goto done2; 457 } 458 error = EINVAL; 459 done2: 460 lwkt_reltoken(&vkp->token); 461 done3: 462 return (error); 463 } 464 465 /* 466 * vmspace_mcontrol(id, addr, len, behav, value) 467 * 468 * madvise/mcontrol support for a vmspace. 469 * 470 * No requirements. 471 */ 472 int 473 sys_vmspace_mcontrol(struct vmspace_mcontrol_args *uap) 474 { 475 struct vkernel_proc *vkp; 476 struct vmspace_entry *ve; 477 vm_offset_t start, end; 478 vm_offset_t tmpaddr = (vm_offset_t)uap->addr + uap->len; 479 int error; 480 481 if ((vkp = curproc->p_vkernel) == NULL) { 482 error = EINVAL; 483 goto done3; 484 } 485 lwkt_gettoken(&vkp->token); 486 if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { 487 error = ENOENT; 488 goto done2; 489 } 490 491 /* 492 * NOTE: kern_madvise() can block so we need to temporarily 493 * ref ve->refs. 494 */ 495 atomic_add_int(&ve->refs, 1); 496 497 /* 498 * This code is basically copied from sys_mcontrol() 499 */ 500 if (uap->behav < 0 || uap->behav > MADV_CONTROL_END) { 501 error = EINVAL; 502 goto done1; 503 } 504 505 if (tmpaddr < (vm_offset_t)uap->addr) { 506 error = EINVAL; 507 goto done1; 508 } 509 if (VM_MAX_USER_ADDRESS > 0 && tmpaddr > VM_MAX_USER_ADDRESS) { 510 error = EINVAL; 511 goto done1; 512 } 513 if (VM_MIN_USER_ADDRESS > 0 && uap->addr < VM_MIN_USER_ADDRESS) { 514 error = EINVAL; 515 goto done1; 516 } 517 518 start = trunc_page((vm_offset_t) uap->addr); 519 end = round_page(tmpaddr); 520 521 error = vm_map_madvise(&ve->vmspace->vm_map, start, end, 522 uap->behav, uap->value); 523 done1: 524 atomic_subtract_int(&ve->refs, 1); 525 done2: 526 lwkt_reltoken(&vkp->token); 527 done3: 528 return (error); 529 } 530 531 /* 532 * Red black tree functions 533 */ 534 static int rb_vmspace_compare(struct vmspace_entry *, struct vmspace_entry *); 535 RB_GENERATE(vmspace_rb_tree, vmspace_entry, rb_entry, rb_vmspace_compare); 536 537 /* 538 * a->start is address, and the only field has to be initialized. 539 * The caller must hold vkp->token. 540 * 541 * The caller must hold vkp->token. 542 */ 543 static int 544 rb_vmspace_compare(struct vmspace_entry *a, struct vmspace_entry *b) 545 { 546 if ((char *)a->id < (char *)b->id) 547 return(-1); 548 else if ((char *)a->id > (char *)b->id) 549 return(1); 550 return(0); 551 } 552 553 /* 554 * The caller must hold vkp->token. 555 */ 556 static 557 int 558 rb_vmspace_delete(struct vmspace_entry *ve, void *data) 559 { 560 struct vkernel_proc *vkp = data; 561 562 KKASSERT(ve->refs == 0); 563 vmspace_entry_delete(ve, vkp); 564 return(0); 565 } 566 567 /* 568 * Remove a vmspace_entry from the RB tree and destroy it. We have to clean 569 * up the pmap, the vm_map, then destroy the vmspace. 570 * 571 * This function must remove the ve immediately before it might potentially 572 * block. 573 * 574 * The caller must hold vkp->token. 575 */ 576 static 577 void 578 vmspace_entry_delete(struct vmspace_entry *ve, struct vkernel_proc *vkp) 579 { 580 RB_REMOVE(vmspace_rb_tree, &vkp->root, ve); 581 582 pmap_remove_pages(vmspace_pmap(ve->vmspace), 583 VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS); 584 vm_map_remove(&ve->vmspace->vm_map, 585 VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS); 586 vmspace_free(ve->vmspace); 587 ve->vmspace = NULL; /* safety */ 588 kfree(ve, M_VKERNEL); 589 } 590 591 /* 592 * Locate the ve for (id), return the ve or NULL. If found this function 593 * will bump ve->refs which prevents the ve from being immediately destroyed 594 * (but it can still be removed). 595 * 596 * The caller must hold vkp->token. 597 */ 598 static 599 struct vmspace_entry * 600 vkernel_find_vmspace(struct vkernel_proc *vkp, void *id) 601 { 602 struct vmspace_entry *ve; 603 struct vmspace_entry key; 604 605 key.id = id; 606 ve = RB_FIND(vmspace_rb_tree, &vkp->root, &key); 607 return (ve); 608 } 609 610 /* 611 * Manage vkernel refs, used by the kernel when fork()ing or exit()ing 612 * a vkernel process. 613 * 614 * No requirements. 615 */ 616 void 617 vkernel_inherit(struct proc *p1, struct proc *p2) 618 { 619 struct vkernel_proc *vkp; 620 621 vkp = p1->p_vkernel; 622 KKASSERT(vkp->refs > 0); 623 atomic_add_int(&vkp->refs, 1); 624 p2->p_vkernel = vkp; 625 } 626 627 /* 628 * No requirements. 629 */ 630 void 631 vkernel_exit(struct proc *p) 632 { 633 struct vkernel_proc *vkp; 634 struct lwp *lp; 635 636 vkp = p->p_vkernel; 637 638 /* 639 * Restore the original VM context if we are killed while running 640 * a different one. 641 * 642 * This isn't supposed to happen. What is supposed to happen is 643 * that the process should enter vkernel_trap() before the handling 644 * the signal. 645 */ 646 RB_FOREACH(lp, lwp_rb_tree, &p->p_lwp_tree) { 647 vkernel_lwp_exit(lp); 648 } 649 650 /* 651 * Dereference the common area 652 */ 653 p->p_vkernel = NULL; 654 KKASSERT(vkp->refs > 0); 655 656 if (atomic_fetchadd_int(&vkp->refs, -1) == 1) { 657 lwkt_gettoken(&vkp->token); 658 RB_SCAN(vmspace_rb_tree, &vkp->root, NULL, 659 rb_vmspace_delete, vkp); 660 lwkt_reltoken(&vkp->token); 661 kfree(vkp, M_VKERNEL); 662 } 663 } 664 665 /* 666 * No requirements. 667 */ 668 void 669 vkernel_lwp_exit(struct lwp *lp) 670 { 671 struct vkernel_lwp *vklp; 672 struct vmspace_entry *ve; 673 674 if ((vklp = lp->lwp_vkernel) != NULL) { 675 if ((ve = vklp->ve) != NULL) { 676 kprintf("Warning, pid %d killed with " 677 "active VC!\n", lp->lwp_proc->p_pid); 678 pmap_setlwpvm(lp, lp->lwp_proc->p_vmspace); 679 vklp->ve = NULL; 680 KKASSERT(ve->refs > 0); 681 atomic_subtract_int(&ve->refs, 1); 682 } 683 lp->lwp_vkernel = NULL; 684 kfree(vklp, M_VKERNEL); 685 } 686 } 687 688 /* 689 * A VM space under virtual kernel control trapped out or made a system call 690 * or otherwise needs to return control to the virtual kernel context. 691 * 692 * No requirements. 693 */ 694 void 695 vkernel_trap(struct lwp *lp, struct trapframe *frame) 696 { 697 struct proc *p = lp->lwp_proc; 698 struct vmspace_entry *ve; 699 struct vkernel_lwp *vklp; 700 int error; 701 702 /* 703 * Which vmspace entry was running? 704 */ 705 vklp = lp->lwp_vkernel; 706 KKASSERT(vklp); 707 708 /* If it's a VMM thread just set the vkernel CR3 back */ 709 if (curthread->td_vmm == NULL) { 710 ve = vklp->ve; 711 KKASSERT(ve != NULL); 712 713 /* 714 * Switch the LWP vmspace back to the virtual kernel's VM space. 715 */ 716 vklp->ve = NULL; 717 pmap_setlwpvm(lp, p->p_vmspace); 718 KKASSERT(ve->refs > 0); 719 atomic_subtract_int(&ve->refs, 1); 720 /* ve is invalid once we kill our ref */ 721 } else { 722 vklp->ve = NULL; 723 vmm_vm_set_guest_cr3(p->p_vkernel->vkernel_cr3); 724 } 725 /* 726 * Copy the emulated process frame to the virtual kernel process. 727 * The emulated process cannot change TLS descriptors so don't 728 * bother saving them, we already have a copy. 729 * 730 * Restore the virtual kernel's saved context so the virtual kernel 731 * process can resume. 732 */ 733 error = copyout(frame, vklp->user_trapframe, sizeof(*frame)); 734 bcopy(&vklp->save_trapframe, frame, sizeof(*frame)); 735 bcopy(&vklp->save_vextframe.vx_tls, &curthread->td_tls, 736 sizeof(vklp->save_vextframe.vx_tls)); 737 set_user_TLS(); 738 cpu_vkernel_trap(frame, error); 739 } 740