1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 /* 30 * System call I/F to doors (outside of vnodes I/F) and misc support 31 * routines 32 */ 33 #include <sys/types.h> 34 #include <sys/systm.h> 35 #include <sys/door.h> 36 #include <sys/door_data.h> 37 #include <sys/proc.h> 38 #include <sys/thread.h> 39 #include <sys/class.h> 40 #include <sys/cred.h> 41 #include <sys/kmem.h> 42 #include <sys/cmn_err.h> 43 #include <sys/stack.h> 44 #include <sys/debug.h> 45 #include <sys/cpuvar.h> 46 #include <sys/file.h> 47 #include <sys/fcntl.h> 48 #include <sys/vnode.h> 49 #include <sys/vfs.h> 50 #include <sys/vfs_opreg.h> 51 #include <sys/sobject.h> 52 #include <sys/schedctl.h> 53 #include <sys/callb.h> 54 #include <sys/ucred.h> 55 56 #include <sys/mman.h> 57 #include <sys/sysmacros.h> 58 #include <sys/vmsystm.h> 59 #include <vm/as.h> 60 #include <vm/hat.h> 61 #include <vm/page.h> 62 #include <vm/seg.h> 63 #include <vm/seg_vn.h> 64 #include <vm/seg_vn.h> 65 66 #include <sys/modctl.h> 67 #include <sys/syscall.h> 68 #include <sys/pathname.h> 69 #include <sys/rctl.h> 70 71 /* 72 * The maximum amount of data (in bytes) that will be transferred using 73 * an intermediate kernel buffer. For sizes greater than this we map 74 * in the destination pages and perform a 1-copy transfer. 75 */ 76 size_t door_max_arg = 16 * 1024; 77 78 /* 79 * Maximum amount of data that will be transferred in a reply to a 80 * door_upcall. Need to guard against a process returning huge amounts 81 * of data and getting the kernel stuck in kmem_alloc. 82 */ 83 size_t door_max_upcall_reply = 1024 * 1024; 84 85 /* 86 * Maximum number of descriptors allowed to be passed in a single 87 * door_call or door_return. We need to allocate kernel memory 88 * for all of them at once, so we can't let it scale without limit. 89 */ 90 uint_t door_max_desc = 1024; 91 92 /* 93 * Definition of a door handle, used by other kernel subsystems when 94 * calling door functions. This is really a file structure but we 95 * want to hide that fact. 96 */ 97 struct __door_handle { 98 file_t dh_file; 99 }; 100 101 #define DHTOF(dh) ((file_t *)(dh)) 102 #define FTODH(fp) ((door_handle_t)(fp)) 103 104 static int doorfs(long, long, long, long, long, long); 105 106 static struct sysent door_sysent = { 107 6, 108 SE_ARGC | SE_NOUNLOAD, 109 (int (*)())doorfs, 110 }; 111 112 static struct modlsys modlsys = { 113 &mod_syscallops, "doors", &door_sysent 114 }; 115 116 #ifdef _SYSCALL32_IMPL 117 118 static int 119 doorfs32(int32_t arg1, int32_t arg2, int32_t arg3, int32_t arg4, 120 int32_t arg5, int32_t subcode); 121 122 static struct sysent door_sysent32 = { 123 6, 124 SE_ARGC | SE_NOUNLOAD, 125 (int (*)())doorfs32, 126 }; 127 128 static struct modlsys modlsys32 = { 129 &mod_syscallops32, 130 "32-bit door syscalls", 131 &door_sysent32 132 }; 133 #endif 134 135 static struct modlinkage modlinkage = { 136 MODREV_1, 137 &modlsys, 138 #ifdef _SYSCALL32_IMPL 139 &modlsys32, 140 #endif 141 NULL 142 }; 143 144 dev_t doordev; 145 146 extern struct vfs door_vfs; 147 extern struct vnodeops *door_vnodeops; 148 149 int 150 _init(void) 151 { 152 static const fs_operation_def_t door_vfsops_template[] = { 153 NULL, NULL 154 }; 155 extern const fs_operation_def_t door_vnodeops_template[]; 156 vfsops_t *door_vfsops; 157 major_t major; 158 int error; 159 160 mutex_init(&door_knob, NULL, MUTEX_DEFAULT, NULL); 161 if ((major = getudev()) == (major_t)-1) 162 return (ENXIO); 163 doordev = makedevice(major, 0); 164 165 /* Create a dummy vfs */ 166 error = vfs_makefsops(door_vfsops_template, &door_vfsops); 167 if (error != 0) { 168 cmn_err(CE_WARN, "door init: bad vfs ops"); 169 return (error); 170 } 171 VFS_INIT(&door_vfs, door_vfsops, NULL); 172 door_vfs.vfs_flag = VFS_RDONLY; 173 door_vfs.vfs_dev = doordev; 174 vfs_make_fsid(&(door_vfs.vfs_fsid), doordev, 0); 175 176 error = vn_make_ops("doorfs", door_vnodeops_template, &door_vnodeops); 177 if (error != 0) { 178 vfs_freevfsops(door_vfsops); 179 cmn_err(CE_WARN, "door init: bad vnode ops"); 180 return (error); 181 } 182 return (mod_install(&modlinkage)); 183 } 184 185 int 186 _info(struct modinfo *modinfop) 187 { 188 return (mod_info(&modlinkage, modinfop)); 189 } 190 191 /* system call functions */ 192 static int door_call(int, void *); 193 static int door_return(caddr_t, size_t, door_desc_t *, uint_t, caddr_t, size_t); 194 static int door_create(void (*pc_cookie)(void *, char *, size_t, door_desc_t *, 195 uint_t), void *data_cookie, uint_t); 196 static int door_revoke(int); 197 static int door_info(int, struct door_info *); 198 static int door_ucred(struct ucred_s *); 199 static int door_bind(int); 200 static int door_unbind(void); 201 static int door_unref(void); 202 static int door_getparam(int, int, size_t *); 203 static int door_setparam(int, int, size_t); 204 205 #define DOOR_RETURN_OLD 4 /* historic value, for s10 */ 206 207 /* 208 * System call wrapper for all door related system calls 209 */ 210 static int 211 doorfs(long arg1, long arg2, long arg3, long arg4, long arg5, long subcode) 212 { 213 switch (subcode) { 214 case DOOR_CALL: 215 return (door_call(arg1, (void *)arg2)); 216 case DOOR_RETURN: { 217 door_return_desc_t *drdp = (door_return_desc_t *)arg3; 218 219 if (drdp != NULL) { 220 door_return_desc_t drd; 221 if (copyin(drdp, &drd, sizeof (drd))) 222 return (EFAULT); 223 return (door_return((caddr_t)arg1, arg2, drd.desc_ptr, 224 drd.desc_num, (caddr_t)arg4, arg5)); 225 } 226 return (door_return((caddr_t)arg1, arg2, NULL, 227 0, (caddr_t)arg4, arg5)); 228 } 229 case DOOR_RETURN_OLD: 230 /* 231 * In order to support the S10 runtime environment, we 232 * still respond to the old syscall subcode for door_return. 233 * We treat it as having no stack limits. This code should 234 * be removed when such support is no longer needed. 235 */ 236 return (door_return((caddr_t)arg1, arg2, (door_desc_t *)arg3, 237 arg4, (caddr_t)arg5, 0)); 238 case DOOR_CREATE: 239 return (door_create((void (*)())arg1, (void *)arg2, arg3)); 240 case DOOR_REVOKE: 241 return (door_revoke(arg1)); 242 case DOOR_INFO: 243 return (door_info(arg1, (struct door_info *)arg2)); 244 case DOOR_BIND: 245 return (door_bind(arg1)); 246 case DOOR_UNBIND: 247 return (door_unbind()); 248 case DOOR_UNREFSYS: 249 return (door_unref()); 250 case DOOR_UCRED: 251 return (door_ucred((struct ucred_s *)arg1)); 252 case DOOR_GETPARAM: 253 return (door_getparam(arg1, arg2, (size_t *)arg3)); 254 case DOOR_SETPARAM: 255 return (door_setparam(arg1, arg2, arg3)); 256 default: 257 return (set_errno(EINVAL)); 258 } 259 } 260 261 #ifdef _SYSCALL32_IMPL 262 /* 263 * System call wrapper for all door related system calls from 32-bit programs. 264 * Needed at the moment because of the casts - they undo some damage 265 * that truss causes (sign-extending the stack pointer) when truss'ing 266 * a 32-bit program using doors. 267 */ 268 static int 269 doorfs32(int32_t arg1, int32_t arg2, int32_t arg3, 270 int32_t arg4, int32_t arg5, int32_t subcode) 271 { 272 switch (subcode) { 273 case DOOR_CALL: 274 return (door_call(arg1, (void *)(uintptr_t)(caddr32_t)arg2)); 275 case DOOR_RETURN: { 276 door_return_desc32_t *drdp = 277 (door_return_desc32_t *)(uintptr_t)(caddr32_t)arg3; 278 if (drdp != NULL) { 279 door_return_desc32_t drd; 280 if (copyin(drdp, &drd, sizeof (drd))) 281 return (EFAULT); 282 return (door_return( 283 (caddr_t)(uintptr_t)(caddr32_t)arg1, arg2, 284 (door_desc_t *)(uintptr_t)drd.desc_ptr, 285 drd.desc_num, (caddr_t)(uintptr_t)(caddr32_t)arg4, 286 (size_t)(uintptr_t)(size32_t)arg5)); 287 } 288 return (door_return((caddr_t)(uintptr_t)(caddr32_t)arg1, 289 arg2, NULL, 0, (caddr_t)(uintptr_t)(caddr32_t)arg4, 290 (size_t)(uintptr_t)(size32_t)arg5)); 291 } 292 case DOOR_RETURN_OLD: 293 /* 294 * In order to support the S10 runtime environment, we 295 * still respond to the old syscall subcode for door_return. 296 * We treat it as having no stack limits. This code should 297 * be removed when such support is no longer needed. 298 */ 299 return (door_return((caddr_t)(uintptr_t)(caddr32_t)arg1, arg2, 300 (door_desc_t *)(uintptr_t)(caddr32_t)arg3, arg4, 301 (caddr_t)(uintptr_t)(caddr32_t)arg5, 0)); 302 case DOOR_CREATE: 303 return (door_create((void (*)())(uintptr_t)(caddr32_t)arg1, 304 (void *)(uintptr_t)(caddr32_t)arg2, arg3)); 305 case DOOR_REVOKE: 306 return (door_revoke(arg1)); 307 case DOOR_INFO: 308 return (door_info(arg1, 309 (struct door_info *)(uintptr_t)(caddr32_t)arg2)); 310 case DOOR_BIND: 311 return (door_bind(arg1)); 312 case DOOR_UNBIND: 313 return (door_unbind()); 314 case DOOR_UNREFSYS: 315 return (door_unref()); 316 case DOOR_UCRED: 317 return (door_ucred( 318 (struct ucred_s *)(uintptr_t)(caddr32_t)arg1)); 319 case DOOR_GETPARAM: 320 return (door_getparam(arg1, arg2, 321 (size_t *)(uintptr_t)(caddr32_t)arg3)); 322 case DOOR_SETPARAM: 323 return (door_setparam(arg1, arg2, (size_t)(size32_t)arg3)); 324 325 default: 326 return (set_errno(EINVAL)); 327 } 328 } 329 #endif 330 331 void shuttle_resume(kthread_t *, kmutex_t *); 332 void shuttle_swtch(kmutex_t *); 333 void shuttle_sleep(kthread_t *); 334 335 /* 336 * Support routines 337 */ 338 static int door_create_common(void (*)(), void *, uint_t, int, int *, 339 file_t **); 340 static int door_overflow(kthread_t *, caddr_t, size_t, door_desc_t *, uint_t); 341 static int door_args(kthread_t *, int); 342 static int door_results(kthread_t *, caddr_t, size_t, door_desc_t *, uint_t); 343 static int door_copy(struct as *, caddr_t, caddr_t, uint_t); 344 static void door_server_exit(proc_t *, kthread_t *); 345 static void door_release_server(door_node_t *, kthread_t *); 346 static kthread_t *door_get_server(door_node_t *); 347 static door_node_t *door_lookup(int, file_t **); 348 static int door_translate_in(void); 349 static int door_translate_out(void); 350 static void door_fd_rele(door_desc_t *, uint_t, int); 351 static void door_list_insert(door_node_t *); 352 static void door_info_common(door_node_t *, door_info_t *, file_t *); 353 static int door_release_fds(door_desc_t *, uint_t); 354 static void door_fd_close(door_desc_t *, uint_t); 355 static void door_fp_close(struct file **, uint_t); 356 357 static door_data_t * 358 door_my_data(int create_if_missing) 359 { 360 door_data_t *ddp; 361 362 ddp = curthread->t_door; 363 if (create_if_missing && ddp == NULL) 364 ddp = curthread->t_door = kmem_zalloc(sizeof (*ddp), KM_SLEEP); 365 366 return (ddp); 367 } 368 369 static door_server_t * 370 door_my_server(int create_if_missing) 371 { 372 door_data_t *ddp = door_my_data(create_if_missing); 373 374 return ((ddp != NULL)? DOOR_SERVER(ddp) : NULL); 375 } 376 377 static door_client_t * 378 door_my_client(int create_if_missing) 379 { 380 door_data_t *ddp = door_my_data(create_if_missing); 381 382 return ((ddp != NULL)? DOOR_CLIENT(ddp) : NULL); 383 } 384 385 /* 386 * System call to create a door 387 */ 388 int 389 door_create(void (*pc_cookie)(), void *data_cookie, uint_t attributes) 390 { 391 int fd; 392 int err; 393 394 if ((attributes & ~DOOR_CREATE_MASK) || 395 ((attributes & (DOOR_UNREF | DOOR_UNREF_MULTI)) == 396 (DOOR_UNREF | DOOR_UNREF_MULTI))) 397 return (set_errno(EINVAL)); 398 399 if ((err = door_create_common(pc_cookie, data_cookie, attributes, 0, 400 &fd, NULL)) != 0) 401 return (set_errno(err)); 402 403 f_setfd(fd, FD_CLOEXEC); 404 return (fd); 405 } 406 407 /* 408 * Common code for creating user and kernel doors. If a door was 409 * created, stores a file structure pointer in the location pointed 410 * to by fpp (if fpp is non-NULL) and returns 0. Also, if a non-NULL 411 * pointer to a file descriptor is passed in as fdp, allocates a file 412 * descriptor representing the door. If a door could not be created, 413 * returns an error. 414 */ 415 static int 416 door_create_common(void (*pc_cookie)(), void *data_cookie, uint_t attributes, 417 int from_kernel, int *fdp, file_t **fpp) 418 { 419 door_node_t *dp; 420 vnode_t *vp; 421 struct file *fp; 422 static door_id_t index = 0; 423 proc_t *p = (from_kernel)? &p0 : curproc; 424 425 dp = kmem_zalloc(sizeof (door_node_t), KM_SLEEP); 426 427 dp->door_vnode = vn_alloc(KM_SLEEP); 428 dp->door_target = p; 429 dp->door_data = data_cookie; 430 dp->door_pc = pc_cookie; 431 dp->door_flags = attributes; 432 #ifdef _SYSCALL32_IMPL 433 if (!from_kernel && get_udatamodel() != DATAMODEL_NATIVE) 434 dp->door_data_max = UINT32_MAX; 435 else 436 #endif 437 dp->door_data_max = SIZE_MAX; 438 dp->door_data_min = 0UL; 439 dp->door_desc_max = (attributes & DOOR_REFUSE_DESC)? 0 : INT_MAX; 440 441 vp = DTOV(dp); 442 vn_setops(vp, door_vnodeops); 443 vp->v_type = VDOOR; 444 vp->v_vfsp = &door_vfs; 445 vp->v_data = (caddr_t)dp; 446 mutex_enter(&door_knob); 447 dp->door_index = index++; 448 /* add to per-process door list */ 449 door_list_insert(dp); 450 mutex_exit(&door_knob); 451 452 if (falloc(vp, FREAD | FWRITE, &fp, fdp)) { 453 /* 454 * If the file table is full, remove the door from the 455 * per-process list, free the door, and return NULL. 456 */ 457 mutex_enter(&door_knob); 458 door_list_delete(dp); 459 mutex_exit(&door_knob); 460 vn_free(vp); 461 kmem_free(dp, sizeof (door_node_t)); 462 return (EMFILE); 463 } 464 vn_exists(vp); 465 if (fdp != NULL) 466 setf(*fdp, fp); 467 mutex_exit(&fp->f_tlock); 468 469 if (fpp != NULL) 470 *fpp = fp; 471 return (0); 472 } 473 474 static int 475 door_check_limits(door_node_t *dp, door_arg_t *da, int upcall) 476 { 477 ASSERT(MUTEX_HELD(&door_knob)); 478 479 /* we allow unref upcalls through, despite any minimum */ 480 if (da->data_size < dp->door_data_min && 481 !(upcall && da->data_ptr == DOOR_UNREF_DATA)) 482 return (ENOBUFS); 483 484 if (da->data_size > dp->door_data_max) 485 return (ENOBUFS); 486 487 if (da->desc_num > 0 && (dp->door_flags & DOOR_REFUSE_DESC)) 488 return (ENOTSUP); 489 490 if (da->desc_num > dp->door_desc_max) 491 return (ENFILE); 492 493 return (0); 494 } 495 496 /* 497 * Door invocation. 498 */ 499 int 500 door_call(int did, void *args) 501 { 502 /* Locals */ 503 door_node_t *dp; 504 kthread_t *server_thread; 505 int error = 0; 506 klwp_t *lwp; 507 door_client_t *ct; /* curthread door_data */ 508 door_server_t *st; /* server thread door_data */ 509 door_desc_t *start = NULL; 510 uint_t ncopied = 0; 511 size_t dsize; 512 /* destructor for data returned by a kernel server */ 513 void (*destfn)() = NULL; 514 void *destarg; 515 model_t datamodel; 516 int gotresults = 0; 517 int cancel_pending; 518 519 lwp = ttolwp(curthread); 520 datamodel = lwp_getdatamodel(lwp); 521 522 ct = door_my_client(1); 523 524 /* 525 * Get the arguments 526 */ 527 if (args) { 528 if (datamodel == DATAMODEL_NATIVE) { 529 if (copyin(args, &ct->d_args, sizeof (door_arg_t)) != 0) 530 return (set_errno(EFAULT)); 531 } else { 532 door_arg32_t da32; 533 534 if (copyin(args, &da32, sizeof (door_arg32_t)) != 0) 535 return (set_errno(EFAULT)); 536 ct->d_args.data_ptr = 537 (char *)(uintptr_t)da32.data_ptr; 538 ct->d_args.data_size = da32.data_size; 539 ct->d_args.desc_ptr = 540 (door_desc_t *)(uintptr_t)da32.desc_ptr; 541 ct->d_args.desc_num = da32.desc_num; 542 ct->d_args.rbuf = 543 (char *)(uintptr_t)da32.rbuf; 544 ct->d_args.rsize = da32.rsize; 545 } 546 } else { 547 /* No arguments, and no results allowed */ 548 ct->d_noresults = 1; 549 ct->d_args.data_size = 0; 550 ct->d_args.desc_num = 0; 551 ct->d_args.rsize = 0; 552 } 553 554 if ((dp = door_lookup(did, NULL)) == NULL) 555 return (set_errno(EBADF)); 556 557 mutex_enter(&door_knob); 558 if (DOOR_INVALID(dp)) { 559 mutex_exit(&door_knob); 560 error = EBADF; 561 goto out; 562 } 563 564 /* 565 * before we do anything, check that we are not overflowing the 566 * required limits. 567 */ 568 error = door_check_limits(dp, &ct->d_args, 0); 569 if (error != 0) { 570 mutex_exit(&door_knob); 571 goto out; 572 } 573 574 /* 575 * Check for in-kernel door server. 576 */ 577 if (dp->door_target == &p0) { 578 caddr_t rbuf = ct->d_args.rbuf; 579 size_t rsize = ct->d_args.rsize; 580 581 dp->door_active++; 582 ct->d_kernel = 1; 583 ct->d_error = DOOR_WAIT; 584 mutex_exit(&door_knob); 585 /* translate file descriptors to vnodes */ 586 if (ct->d_args.desc_num) { 587 error = door_translate_in(); 588 if (error) 589 goto out; 590 } 591 /* 592 * Call kernel door server. Arguments are passed and 593 * returned as a door_arg pointer. When called, data_ptr 594 * points to user data and desc_ptr points to a kernel list 595 * of door descriptors that have been converted to file 596 * structure pointers. It's the server function's 597 * responsibility to copyin the data pointed to by data_ptr 598 * (this avoids extra copying in some cases). On return, 599 * data_ptr points to a user buffer of data, and desc_ptr 600 * points to a kernel list of door descriptors representing 601 * files. When a reference is passed to a kernel server, 602 * it is the server's responsibility to release the reference 603 * (by calling closef). When the server includes a 604 * reference in its reply, it is released as part of the 605 * the call (the server must duplicate the reference if 606 * it wants to retain a copy). The destfn, if set to 607 * non-NULL, is a destructor to be called when the returned 608 * kernel data (if any) is no longer needed (has all been 609 * translated and copied to user level). 610 */ 611 (*(dp->door_pc))(dp->door_data, &ct->d_args, 612 &destfn, &destarg, &error); 613 mutex_enter(&door_knob); 614 /* not implemented yet */ 615 if (--dp->door_active == 0 && (dp->door_flags & DOOR_DELAY)) 616 door_deliver_unref(dp); 617 mutex_exit(&door_knob); 618 if (error) 619 goto out; 620 621 /* translate vnodes to files */ 622 if (ct->d_args.desc_num) { 623 error = door_translate_out(); 624 if (error) 625 goto out; 626 } 627 ct->d_buf = ct->d_args.rbuf; 628 ct->d_bufsize = ct->d_args.rsize; 629 if (rsize < (ct->d_args.data_size + 630 (ct->d_args.desc_num * sizeof (door_desc_t)))) { 631 /* handle overflow */ 632 error = door_overflow(curthread, ct->d_args.data_ptr, 633 ct->d_args.data_size, ct->d_args.desc_ptr, 634 ct->d_args.desc_num); 635 if (error) 636 goto out; 637 /* door_overflow sets d_args rbuf and rsize */ 638 } else { 639 ct->d_args.rbuf = rbuf; 640 ct->d_args.rsize = rsize; 641 } 642 goto results; 643 } 644 645 /* 646 * Get a server thread from the target domain 647 */ 648 if ((server_thread = door_get_server(dp)) == NULL) { 649 if (DOOR_INVALID(dp)) 650 error = EBADF; 651 else 652 error = EAGAIN; 653 mutex_exit(&door_knob); 654 goto out; 655 } 656 657 st = DOOR_SERVER(server_thread->t_door); 658 if (ct->d_args.desc_num || ct->d_args.data_size) { 659 int is_private = (dp->door_flags & DOOR_PRIVATE); 660 /* 661 * Move data from client to server 662 */ 663 DOOR_T_HOLD(st); 664 mutex_exit(&door_knob); 665 error = door_args(server_thread, is_private); 666 mutex_enter(&door_knob); 667 DOOR_T_RELEASE(st); 668 if (error) { 669 /* 670 * We're not going to resume this thread after all 671 */ 672 door_release_server(dp, server_thread); 673 shuttle_sleep(server_thread); 674 mutex_exit(&door_knob); 675 goto out; 676 } 677 } 678 679 dp->door_active++; 680 ct->d_error = DOOR_WAIT; 681 st->d_caller = curthread; 682 st->d_active = dp; 683 684 shuttle_resume(server_thread, &door_knob); 685 686 mutex_enter(&door_knob); 687 shuttle_return: 688 if ((error = ct->d_error) < 0) { /* DOOR_WAIT or DOOR_EXIT */ 689 /* 690 * Premature wakeup. Find out why (stop, forkall, sig, exit ...) 691 */ 692 mutex_exit(&door_knob); /* May block in ISSIG */ 693 cancel_pending = 0; 694 if (ISSIG(curthread, FORREAL) || lwp->lwp_sysabort || 695 MUSTRETURN(curproc, curthread) || 696 (cancel_pending = schedctl_cancel_pending()) != 0) { 697 /* Signal, forkall, ... */ 698 lwp->lwp_sysabort = 0; 699 if (cancel_pending) 700 schedctl_cancel_eintr(); 701 mutex_enter(&door_knob); 702 error = EINTR; 703 /* 704 * If the server has finished processing our call, 705 * or exited (calling door_slam()), then d_error 706 * will have changed. If the server hasn't finished 707 * yet, d_error will still be DOOR_WAIT, and we 708 * let it know we are not interested in any 709 * results by sending a SIGCANCEL, unless the door 710 * is marked with DOOR_NO_CANCEL. 711 */ 712 if (ct->d_error == DOOR_WAIT && 713 st->d_caller == curthread) { 714 proc_t *p = ttoproc(server_thread); 715 716 st->d_active = NULL; 717 st->d_caller = NULL; 718 719 if (!(dp->door_flags & DOOR_NO_CANCEL)) { 720 DOOR_T_HOLD(st); 721 mutex_exit(&door_knob); 722 723 mutex_enter(&p->p_lock); 724 sigtoproc(p, server_thread, SIGCANCEL); 725 mutex_exit(&p->p_lock); 726 727 mutex_enter(&door_knob); 728 DOOR_T_RELEASE(st); 729 } 730 } 731 } else { 732 /* 733 * Return from stop(), server exit... 734 * 735 * Note that the server could have done a 736 * door_return while the client was in stop state 737 * (ISSIG), in which case the error condition 738 * is updated by the server. 739 */ 740 mutex_enter(&door_knob); 741 if (ct->d_error == DOOR_WAIT) { 742 /* Still waiting for a reply */ 743 shuttle_swtch(&door_knob); 744 mutex_enter(&door_knob); 745 lwp->lwp_asleep = 0; 746 goto shuttle_return; 747 } else if (ct->d_error == DOOR_EXIT) { 748 /* Server exit */ 749 error = EINTR; 750 } else { 751 /* Server did a door_return during ISSIG */ 752 error = ct->d_error; 753 } 754 } 755 /* 756 * Can't exit if the server is currently copying 757 * results for me. 758 */ 759 while (DOOR_T_HELD(ct)) 760 cv_wait(&ct->d_cv, &door_knob); 761 762 /* 763 * Find out if results were successfully copied. 764 */ 765 if (ct->d_error == 0) 766 gotresults = 1; 767 } 768 lwp->lwp_asleep = 0; /* /proc */ 769 lwp->lwp_sysabort = 0; /* /proc */ 770 if (--dp->door_active == 0 && (dp->door_flags & DOOR_DELAY)) 771 door_deliver_unref(dp); 772 mutex_exit(&door_knob); 773 774 results: 775 /* 776 * Move the results to userland (if any) 777 */ 778 779 if (ct->d_noresults) 780 goto out; 781 782 if (error) { 783 /* 784 * If server returned results successfully, then we've 785 * been interrupted and may need to clean up. 786 */ 787 if (gotresults) { 788 ASSERT(error == EINTR); 789 door_fp_close(ct->d_fpp, ct->d_args.desc_num); 790 } 791 goto out; 792 } 793 794 /* 795 * Copy back data if we haven't caused an overflow (already 796 * handled) and we are using a 2 copy transfer, or we are 797 * returning data from a kernel server. 798 */ 799 if (ct->d_args.data_size) { 800 ct->d_args.data_ptr = ct->d_args.rbuf; 801 if (ct->d_kernel || (!ct->d_overflow && 802 ct->d_args.data_size <= door_max_arg)) { 803 if (copyout(ct->d_buf, ct->d_args.rbuf, 804 ct->d_args.data_size)) { 805 door_fp_close(ct->d_fpp, ct->d_args.desc_num); 806 error = EFAULT; 807 goto out; 808 } 809 } 810 } 811 812 /* 813 * stuff returned doors into our proc, copyout the descriptors 814 */ 815 if (ct->d_args.desc_num) { 816 struct file **fpp; 817 door_desc_t *didpp; 818 uint_t n = ct->d_args.desc_num; 819 820 dsize = n * sizeof (door_desc_t); 821 start = didpp = kmem_alloc(dsize, KM_SLEEP); 822 fpp = ct->d_fpp; 823 824 while (n--) { 825 if (door_insert(*fpp, didpp) == -1) { 826 /* Close remaining files */ 827 door_fp_close(fpp, n + 1); 828 error = EMFILE; 829 goto out; 830 } 831 fpp++; didpp++; ncopied++; 832 } 833 834 ct->d_args.desc_ptr = (door_desc_t *)(ct->d_args.rbuf + 835 roundup(ct->d_args.data_size, sizeof (door_desc_t))); 836 837 if (copyout(start, ct->d_args.desc_ptr, dsize)) { 838 error = EFAULT; 839 goto out; 840 } 841 } 842 843 /* 844 * Return the results 845 */ 846 if (datamodel == DATAMODEL_NATIVE) { 847 if (copyout(&ct->d_args, args, sizeof (door_arg_t)) != 0) 848 error = EFAULT; 849 } else { 850 door_arg32_t da32; 851 852 da32.data_ptr = (caddr32_t)(uintptr_t)ct->d_args.data_ptr; 853 da32.data_size = ct->d_args.data_size; 854 da32.desc_ptr = (caddr32_t)(uintptr_t)ct->d_args.desc_ptr; 855 da32.desc_num = ct->d_args.desc_num; 856 da32.rbuf = (caddr32_t)(uintptr_t)ct->d_args.rbuf; 857 da32.rsize = ct->d_args.rsize; 858 if (copyout(&da32, args, sizeof (door_arg32_t)) != 0) { 859 error = EFAULT; 860 } 861 } 862 863 out: 864 ct->d_noresults = 0; 865 866 /* clean up the overflow buffer if an error occurred */ 867 if (error != 0 && ct->d_overflow) { 868 (void) as_unmap(curproc->p_as, ct->d_args.rbuf, 869 ct->d_args.rsize); 870 } 871 ct->d_overflow = 0; 872 873 /* call destructor */ 874 if (destfn) { 875 ASSERT(ct->d_kernel); 876 (*destfn)(dp->door_data, destarg); 877 ct->d_buf = NULL; 878 ct->d_bufsize = 0; 879 } 880 881 if (dp) 882 releasef(did); 883 884 if (ct->d_buf) { 885 ASSERT(!ct->d_kernel); 886 kmem_free(ct->d_buf, ct->d_bufsize); 887 ct->d_buf = NULL; 888 ct->d_bufsize = 0; 889 } 890 ct->d_kernel = 0; 891 892 /* clean up the descriptor copyout buffer */ 893 if (start != NULL) { 894 if (error != 0) 895 door_fd_close(start, ncopied); 896 kmem_free(start, dsize); 897 } 898 899 if (ct->d_fpp) { 900 kmem_free(ct->d_fpp, ct->d_fpp_size); 901 ct->d_fpp = NULL; 902 ct->d_fpp_size = 0; 903 } 904 905 if (error) 906 return (set_errno(error)); 907 908 return (0); 909 } 910 911 static int 912 door_setparam_common(door_node_t *dp, int from_kernel, int type, size_t val) 913 { 914 int error = 0; 915 916 mutex_enter(&door_knob); 917 918 if (DOOR_INVALID(dp)) { 919 mutex_exit(&door_knob); 920 return (EBADF); 921 } 922 923 /* 924 * door_ki_setparam() can only affect kernel doors. 925 * door_setparam() can only affect doors attached to the current 926 * process. 927 */ 928 if ((from_kernel && dp->door_target != &p0) || 929 (!from_kernel && dp->door_target != curproc)) { 930 mutex_exit(&door_knob); 931 return (EPERM); 932 } 933 934 switch (type) { 935 case DOOR_PARAM_DESC_MAX: 936 if (val > INT_MAX) 937 error = ERANGE; 938 else if ((dp->door_flags & DOOR_REFUSE_DESC) && val != 0) 939 error = ENOTSUP; 940 else 941 dp->door_desc_max = (uint_t)val; 942 break; 943 944 case DOOR_PARAM_DATA_MIN: 945 if (val > dp->door_data_max) 946 error = EINVAL; 947 else 948 dp->door_data_min = val; 949 break; 950 951 case DOOR_PARAM_DATA_MAX: 952 if (val < dp->door_data_min) 953 error = EINVAL; 954 else 955 dp->door_data_max = val; 956 break; 957 958 default: 959 error = EINVAL; 960 break; 961 } 962 963 mutex_exit(&door_knob); 964 return (error); 965 } 966 967 static int 968 door_getparam_common(door_node_t *dp, int type, size_t *out) 969 { 970 int error = 0; 971 972 mutex_enter(&door_knob); 973 switch (type) { 974 case DOOR_PARAM_DESC_MAX: 975 *out = (size_t)dp->door_desc_max; 976 break; 977 case DOOR_PARAM_DATA_MIN: 978 *out = dp->door_data_min; 979 break; 980 case DOOR_PARAM_DATA_MAX: 981 *out = dp->door_data_max; 982 break; 983 default: 984 error = EINVAL; 985 break; 986 } 987 mutex_exit(&door_knob); 988 return (error); 989 } 990 991 int 992 door_setparam(int did, int type, size_t val) 993 { 994 door_node_t *dp; 995 int error = 0; 996 997 if ((dp = door_lookup(did, NULL)) == NULL) 998 return (set_errno(EBADF)); 999 1000 error = door_setparam_common(dp, 0, type, val); 1001 1002 releasef(did); 1003 1004 if (error) 1005 return (set_errno(error)); 1006 1007 return (0); 1008 } 1009 1010 int 1011 door_getparam(int did, int type, size_t *out) 1012 { 1013 door_node_t *dp; 1014 size_t val = 0; 1015 int error = 0; 1016 1017 if ((dp = door_lookup(did, NULL)) == NULL) 1018 return (set_errno(EBADF)); 1019 1020 error = door_getparam_common(dp, type, &val); 1021 1022 releasef(did); 1023 1024 if (error) 1025 return (set_errno(error)); 1026 1027 if (get_udatamodel() == DATAMODEL_NATIVE) { 1028 if (copyout(&val, out, sizeof (val))) 1029 return (set_errno(EFAULT)); 1030 #ifdef _SYSCALL32_IMPL 1031 } else { 1032 size32_t val32 = (size32_t)val; 1033 1034 if (val != val32) 1035 return (set_errno(EOVERFLOW)); 1036 1037 if (copyout(&val32, out, sizeof (val32))) 1038 return (set_errno(EFAULT)); 1039 #endif /* _SYSCALL32_IMPL */ 1040 } 1041 1042 return (0); 1043 } 1044 1045 /* 1046 * A copyout() which proceeds from high addresses to low addresses. This way, 1047 * stack guard pages are effective. 1048 */ 1049 static int 1050 door_stack_copyout(const void *kaddr, void *uaddr, size_t count) 1051 { 1052 const char *kbase = (const char *)kaddr; 1053 uintptr_t ubase = (uintptr_t)uaddr; 1054 size_t pgsize = PAGESIZE; 1055 1056 if (count <= pgsize) 1057 return (copyout(kaddr, uaddr, count)); 1058 1059 while (count > 0) { 1060 uintptr_t start, end, offset, amount; 1061 1062 end = ubase + count; 1063 start = P2ALIGN(end - 1, pgsize); 1064 if (P2ALIGN(ubase, pgsize) == start) 1065 start = ubase; 1066 1067 offset = start - ubase; 1068 amount = end - start; 1069 1070 ASSERT(amount > 0 && amount <= count && amount <= pgsize); 1071 1072 if (copyout(kbase + offset, (void *)start, amount)) 1073 return (1); 1074 count -= amount; 1075 } 1076 return (0); 1077 } 1078 1079 /* 1080 * Writes the stack layout for door_return() into the door_server_t of the 1081 * server thread. 1082 */ 1083 static int 1084 door_layout(kthread_t *tp, size_t data_size, uint_t ndesc, int info_needed) 1085 { 1086 door_server_t *st = DOOR_SERVER(tp->t_door); 1087 door_layout_t *out = &st->d_layout; 1088 uintptr_t base_sp = (uintptr_t)st->d_sp; 1089 size_t ssize = st->d_ssize; 1090 size_t descsz; 1091 uintptr_t descp, datap, infop, resultsp, finalsp; 1092 size_t align = STACK_ALIGN; 1093 size_t results_sz = sizeof (struct door_results); 1094 model_t datamodel = lwp_getdatamodel(ttolwp(tp)); 1095 1096 ASSERT(!st->d_layout_done); 1097 1098 #ifndef _STACK_GROWS_DOWNWARD 1099 #error stack does not grow downward, door_layout() must change 1100 #endif 1101 1102 #ifdef _SYSCALL32_IMPL 1103 if (datamodel != DATAMODEL_NATIVE) { 1104 align = STACK_ALIGN32; 1105 results_sz = sizeof (struct door_results32); 1106 } 1107 #endif 1108 1109 descsz = ndesc * sizeof (door_desc_t); 1110 1111 /* 1112 * To speed up the overflow checking, we do an initial check 1113 * that the passed in data size won't cause us to wrap past 1114 * base_sp. Since door_max_desc limits descsz, we can 1115 * safely use it here. 65535 is an arbitrary 'bigger than 1116 * we need, small enough to not cause trouble' constant; 1117 * the only constraint is that it must be > than: 1118 * 1119 * 5 * STACK_ALIGN + 1120 * sizeof (door_info_t) + 1121 * sizeof (door_results_t) + 1122 * (max adjustment from door_final_sp()) 1123 * 1124 * After we compute the layout, we can safely do a "did we wrap 1125 * around" check, followed by a check against the recorded 1126 * stack size. 1127 */ 1128 if (data_size >= SIZE_MAX - (size_t)65535UL - descsz) 1129 return (E2BIG); /* overflow */ 1130 1131 descp = P2ALIGN(base_sp - descsz, align); 1132 datap = P2ALIGN(descp - data_size, align); 1133 1134 if (info_needed) 1135 infop = P2ALIGN(datap - sizeof (door_info_t), align); 1136 else 1137 infop = datap; 1138 1139 resultsp = P2ALIGN(infop - results_sz, align); 1140 finalsp = door_final_sp(resultsp, align, datamodel); 1141 1142 if (finalsp > base_sp) 1143 return (E2BIG); /* overflow */ 1144 1145 if (ssize != 0 && (base_sp - finalsp) > ssize) 1146 return (E2BIG); /* doesn't fit in stack */ 1147 1148 out->dl_descp = (ndesc != 0)? (caddr_t)descp : 0; 1149 out->dl_datap = (data_size != 0)? (caddr_t)datap : 0; 1150 out->dl_infop = info_needed? (caddr_t)infop : 0; 1151 out->dl_resultsp = (caddr_t)resultsp; 1152 out->dl_sp = (caddr_t)finalsp; 1153 1154 st->d_layout_done = 1; 1155 return (0); 1156 } 1157 1158 static int 1159 door_server_dispatch(door_client_t *ct, door_node_t *dp) 1160 { 1161 door_server_t *st = DOOR_SERVER(curthread->t_door); 1162 door_layout_t *layout = &st->d_layout; 1163 int error = 0; 1164 1165 int is_private = (dp->door_flags & DOOR_PRIVATE); 1166 1167 door_pool_t *pool = (is_private)? &dp->door_servers : 1168 &curproc->p_server_threads; 1169 1170 int empty_pool = (pool->dp_threads == NULL); 1171 1172 caddr_t infop = NULL; 1173 char *datap = NULL; 1174 size_t datasize = 0; 1175 size_t descsize; 1176 1177 file_t **fpp = ct->d_fpp; 1178 door_desc_t *start = NULL; 1179 uint_t ndesc = 0; 1180 uint_t ncopied = 0; 1181 1182 if (ct != NULL) { 1183 datap = ct->d_args.data_ptr; 1184 datasize = ct->d_args.data_size; 1185 ndesc = ct->d_args.desc_num; 1186 } 1187 1188 descsize = ndesc * sizeof (door_desc_t); 1189 1190 /* 1191 * Reset datap to NULL if we aren't passing any data. Be careful 1192 * to let unref notifications through, though. 1193 */ 1194 if (datap == DOOR_UNREF_DATA) { 1195 if (ct->d_upcall) 1196 datasize = 0; 1197 else 1198 datap = NULL; 1199 } else if (datasize == 0) { 1200 datap = NULL; 1201 } 1202 1203 /* 1204 * Get the stack layout, if it hasn't already been done. 1205 */ 1206 if (!st->d_layout_done) { 1207 error = door_layout(curthread, datasize, ndesc, 1208 (is_private && empty_pool)); 1209 if (error != 0) 1210 goto fail; 1211 } 1212 1213 /* 1214 * fill out the stack, starting from the top. Layout was already 1215 * filled in by door_args() or door_translate_out(). 1216 */ 1217 if (layout->dl_descp != NULL) { 1218 ASSERT(ndesc != 0); 1219 start = kmem_alloc(descsize, KM_SLEEP); 1220 1221 while (ndesc > 0) { 1222 if (door_insert(*fpp, &start[ncopied]) == -1) { 1223 error = EMFILE; 1224 goto fail; 1225 } 1226 ndesc--; 1227 ncopied++; 1228 fpp++; 1229 } 1230 if (door_stack_copyout(start, layout->dl_descp, descsize)) { 1231 error = E2BIG; 1232 goto fail; 1233 } 1234 } 1235 fpp = NULL; /* finished processing */ 1236 1237 if (layout->dl_datap != NULL) { 1238 ASSERT(datasize != 0); 1239 datap = layout->dl_datap; 1240 if (ct->d_upcall || datasize <= door_max_arg) { 1241 if (door_stack_copyout(ct->d_buf, datap, datasize)) { 1242 error = E2BIG; 1243 goto fail; 1244 } 1245 } 1246 } 1247 1248 if (is_private && empty_pool) { 1249 door_info_t di; 1250 1251 infop = layout->dl_infop; 1252 ASSERT(infop != NULL); 1253 1254 di.di_target = curproc->p_pid; 1255 di.di_proc = (door_ptr_t)(uintptr_t)dp->door_pc; 1256 di.di_data = (door_ptr_t)(uintptr_t)dp->door_data; 1257 di.di_uniquifier = dp->door_index; 1258 di.di_attributes = (dp->door_flags & DOOR_ATTR_MASK) | 1259 DOOR_LOCAL; 1260 1261 if (copyout(&di, infop, sizeof (di))) { 1262 error = E2BIG; 1263 goto fail; 1264 } 1265 } 1266 1267 if (get_udatamodel() == DATAMODEL_NATIVE) { 1268 struct door_results dr; 1269 1270 dr.cookie = dp->door_data; 1271 dr.data_ptr = datap; 1272 dr.data_size = datasize; 1273 dr.desc_ptr = (door_desc_t *)layout->dl_descp; 1274 dr.desc_num = ncopied; 1275 dr.pc = dp->door_pc; 1276 dr.nservers = !empty_pool; 1277 dr.door_info = (door_info_t *)infop; 1278 1279 if (copyout(&dr, layout->dl_resultsp, sizeof (dr))) { 1280 error = E2BIG; 1281 goto fail; 1282 } 1283 #ifdef _SYSCALL32_IMPL 1284 } else { 1285 struct door_results32 dr32; 1286 1287 dr32.cookie = (caddr32_t)(uintptr_t)dp->door_data; 1288 dr32.data_ptr = (caddr32_t)(uintptr_t)datap; 1289 dr32.data_size = (size32_t)datasize; 1290 dr32.desc_ptr = (caddr32_t)(uintptr_t)layout->dl_descp; 1291 dr32.desc_num = ncopied; 1292 dr32.pc = (caddr32_t)(uintptr_t)dp->door_pc; 1293 dr32.nservers = !empty_pool; 1294 dr32.door_info = (caddr32_t)(uintptr_t)infop; 1295 1296 if (copyout(&dr32, layout->dl_resultsp, sizeof (dr32))) { 1297 error = E2BIG; 1298 goto fail; 1299 } 1300 #endif 1301 } 1302 1303 error = door_finish_dispatch(layout->dl_sp); 1304 fail: 1305 if (start != NULL) { 1306 if (error != 0) 1307 door_fd_close(start, ncopied); 1308 kmem_free(start, descsize); 1309 } 1310 if (fpp != NULL) 1311 door_fp_close(fpp, ndesc); 1312 1313 return (error); 1314 } 1315 1316 /* 1317 * Return the results (if any) to the caller (if any) and wait for the 1318 * next invocation on a door. 1319 */ 1320 int 1321 door_return(caddr_t data_ptr, size_t data_size, 1322 door_desc_t *desc_ptr, uint_t desc_num, caddr_t sp, size_t ssize) 1323 { 1324 kthread_t *caller; 1325 klwp_t *lwp; 1326 int error = 0; 1327 door_node_t *dp; 1328 door_server_t *st; /* curthread door_data */ 1329 door_client_t *ct; /* caller door_data */ 1330 int cancel_pending; 1331 1332 st = door_my_server(1); 1333 1334 /* 1335 * If thread was bound to a door that no longer exists, return 1336 * an error. This can happen if a thread is bound to a door 1337 * before the process calls forkall(); in the child, the door 1338 * doesn't exist and door_fork() sets the d_invbound flag. 1339 */ 1340 if (st->d_invbound) 1341 return (set_errno(EINVAL)); 1342 1343 st->d_sp = sp; /* Save base of stack. */ 1344 st->d_ssize = ssize; /* and its size */ 1345 1346 /* 1347 * before we release our stack to the whims of our next caller, 1348 * copy in the syscall arguments if we're being traced by /proc. 1349 */ 1350 if (curthread->t_post_sys && PTOU(ttoproc(curthread))->u_systrap) 1351 (void) save_syscall_args(); 1352 1353 /* Make sure the caller hasn't gone away */ 1354 mutex_enter(&door_knob); 1355 if ((caller = st->d_caller) == NULL || caller->t_door == NULL) { 1356 if (desc_num != 0) { 1357 /* close any DOOR_RELEASE descriptors */ 1358 mutex_exit(&door_knob); 1359 error = door_release_fds(desc_ptr, desc_num); 1360 if (error) 1361 return (set_errno(error)); 1362 mutex_enter(&door_knob); 1363 } 1364 goto out; 1365 } 1366 ct = DOOR_CLIENT(caller->t_door); 1367 1368 ct->d_args.data_size = data_size; 1369 ct->d_args.desc_num = desc_num; 1370 /* 1371 * Transfer results, if any, to the client 1372 */ 1373 if (data_size != 0 || desc_num != 0) { 1374 /* 1375 * Prevent the client from exiting until we have finished 1376 * moving results. 1377 */ 1378 DOOR_T_HOLD(ct); 1379 mutex_exit(&door_knob); 1380 error = door_results(caller, data_ptr, data_size, 1381 desc_ptr, desc_num); 1382 mutex_enter(&door_knob); 1383 DOOR_T_RELEASE(ct); 1384 /* 1385 * Pass EOVERFLOW errors back to the client 1386 */ 1387 if (error && error != EOVERFLOW) { 1388 mutex_exit(&door_knob); 1389 return (set_errno(error)); 1390 } 1391 } 1392 out: 1393 /* Put ourselves on the available server thread list */ 1394 door_release_server(st->d_pool, curthread); 1395 1396 /* 1397 * Make sure the caller is still waiting to be resumed 1398 */ 1399 if (caller) { 1400 disp_lock_t *tlp; 1401 1402 thread_lock(caller); 1403 ct->d_error = error; /* Return any errors */ 1404 if (caller->t_state == TS_SLEEP && 1405 SOBJ_TYPE(caller->t_sobj_ops) == SOBJ_SHUTTLE) { 1406 cpu_t *cp = CPU; 1407 1408 tlp = caller->t_lockp; 1409 /* 1410 * Setting t_disp_queue prevents erroneous preemptions 1411 * if this thread is still in execution on another 1412 * processor 1413 */ 1414 caller->t_disp_queue = cp->cpu_disp; 1415 CL_ACTIVE(caller); 1416 /* 1417 * We are calling thread_onproc() instead of 1418 * THREAD_ONPROC() because compiler can reorder 1419 * the two stores of t_state and t_lockp in 1420 * THREAD_ONPROC(). 1421 */ 1422 thread_onproc(caller, cp); 1423 disp_lock_exit_high(tlp); 1424 shuttle_resume(caller, &door_knob); 1425 } else { 1426 /* May have been setrun or in stop state */ 1427 thread_unlock(caller); 1428 shuttle_swtch(&door_knob); 1429 } 1430 } else { 1431 shuttle_swtch(&door_knob); 1432 } 1433 1434 /* 1435 * We've sprung to life. Determine if we are part of a door 1436 * invocation, or just interrupted 1437 */ 1438 lwp = ttolwp(curthread); 1439 mutex_enter(&door_knob); 1440 if ((dp = st->d_active) != NULL) { 1441 /* 1442 * Normal door invocation. Return any error condition 1443 * encountered while trying to pass args to the server 1444 * thread. 1445 */ 1446 lwp->lwp_asleep = 0; 1447 /* 1448 * Prevent the caller from leaving us while we 1449 * are copying out the arguments from it's buffer. 1450 */ 1451 ASSERT(st->d_caller != NULL); 1452 ct = DOOR_CLIENT(st->d_caller->t_door); 1453 1454 DOOR_T_HOLD(ct); 1455 mutex_exit(&door_knob); 1456 error = door_server_dispatch(ct, dp); 1457 mutex_enter(&door_knob); 1458 DOOR_T_RELEASE(ct); 1459 1460 if (error) { 1461 caller = st->d_caller; 1462 if (caller) 1463 ct = DOOR_CLIENT(caller->t_door); 1464 else 1465 ct = NULL; 1466 goto out; 1467 } 1468 mutex_exit(&door_knob); 1469 return (0); 1470 } else { 1471 /* 1472 * We are not involved in a door_invocation. 1473 * Check for /proc related activity... 1474 */ 1475 st->d_caller = NULL; 1476 door_server_exit(curproc, curthread); 1477 mutex_exit(&door_knob); 1478 cancel_pending = 0; 1479 if (ISSIG(curthread, FORREAL) || lwp->lwp_sysabort || 1480 MUSTRETURN(curproc, curthread) || 1481 (cancel_pending = schedctl_cancel_pending()) != 0) { 1482 if (cancel_pending) 1483 schedctl_cancel_eintr(); 1484 lwp->lwp_asleep = 0; 1485 lwp->lwp_sysabort = 0; 1486 return (set_errno(EINTR)); 1487 } 1488 /* Go back and wait for another request */ 1489 lwp->lwp_asleep = 0; 1490 mutex_enter(&door_knob); 1491 caller = NULL; 1492 goto out; 1493 } 1494 } 1495 1496 /* 1497 * Revoke any future invocations on this door 1498 */ 1499 int 1500 door_revoke(int did) 1501 { 1502 door_node_t *d; 1503 int error; 1504 1505 if ((d = door_lookup(did, NULL)) == NULL) 1506 return (set_errno(EBADF)); 1507 1508 mutex_enter(&door_knob); 1509 if (d->door_target != curproc) { 1510 mutex_exit(&door_knob); 1511 releasef(did); 1512 return (set_errno(EPERM)); 1513 } 1514 d->door_flags |= DOOR_REVOKED; 1515 if (d->door_flags & DOOR_PRIVATE) 1516 cv_broadcast(&d->door_servers.dp_cv); 1517 else 1518 cv_broadcast(&curproc->p_server_threads.dp_cv); 1519 mutex_exit(&door_knob); 1520 releasef(did); 1521 /* Invalidate the descriptor */ 1522 if ((error = closeandsetf(did, NULL)) != 0) 1523 return (set_errno(error)); 1524 return (0); 1525 } 1526 1527 int 1528 door_info(int did, struct door_info *d_info) 1529 { 1530 door_node_t *dp; 1531 door_info_t di; 1532 door_server_t *st; 1533 file_t *fp = NULL; 1534 1535 if (did == DOOR_QUERY) { 1536 /* Get information on door current thread is bound to */ 1537 if ((st = door_my_server(0)) == NULL || 1538 (dp = st->d_pool) == NULL) 1539 /* Thread isn't bound to a door */ 1540 return (set_errno(EBADF)); 1541 } else if ((dp = door_lookup(did, &fp)) == NULL) { 1542 /* Not a door */ 1543 return (set_errno(EBADF)); 1544 } 1545 1546 door_info_common(dp, &di, fp); 1547 1548 if (did != DOOR_QUERY) 1549 releasef(did); 1550 1551 if (copyout(&di, d_info, sizeof (struct door_info))) 1552 return (set_errno(EFAULT)); 1553 return (0); 1554 } 1555 1556 /* 1557 * Common code for getting information about a door either via the 1558 * door_info system call or the door_ki_info kernel call. 1559 */ 1560 void 1561 door_info_common(door_node_t *dp, struct door_info *dip, file_t *fp) 1562 { 1563 int unref_count; 1564 1565 bzero(dip, sizeof (door_info_t)); 1566 1567 mutex_enter(&door_knob); 1568 if (dp->door_target == NULL) 1569 dip->di_target = -1; 1570 else 1571 dip->di_target = dp->door_target->p_pid; 1572 1573 dip->di_attributes = dp->door_flags & DOOR_ATTR_MASK; 1574 if (dp->door_target == curproc) 1575 dip->di_attributes |= DOOR_LOCAL; 1576 dip->di_proc = (door_ptr_t)(uintptr_t)dp->door_pc; 1577 dip->di_data = (door_ptr_t)(uintptr_t)dp->door_data; 1578 dip->di_uniquifier = dp->door_index; 1579 /* 1580 * If this door is in the middle of having an unreferenced 1581 * notification delivered, don't count the VN_HOLD by 1582 * door_deliver_unref in determining if it is unreferenced. 1583 * This handles the case where door_info is called from the 1584 * thread delivering the unref notification. 1585 */ 1586 if (dp->door_flags & DOOR_UNREF_ACTIVE) 1587 unref_count = 2; 1588 else 1589 unref_count = 1; 1590 mutex_exit(&door_knob); 1591 1592 if (fp == NULL) { 1593 /* 1594 * If this thread is bound to the door, then we can just 1595 * check the vnode; a ref count of 1 (or 2 if this is 1596 * handling an unref notification) means that the hold 1597 * from the door_bind is the only reference to the door 1598 * (no file descriptor refers to it). 1599 */ 1600 if (DTOV(dp)->v_count == unref_count) 1601 dip->di_attributes |= DOOR_IS_UNREF; 1602 } else { 1603 /* 1604 * If we're working from a file descriptor or door handle 1605 * we need to look at the file structure count. We don't 1606 * need to hold the vnode lock since this is just a snapshot. 1607 */ 1608 mutex_enter(&fp->f_tlock); 1609 if (fp->f_count == 1 && DTOV(dp)->v_count == unref_count) 1610 dip->di_attributes |= DOOR_IS_UNREF; 1611 mutex_exit(&fp->f_tlock); 1612 } 1613 } 1614 1615 /* 1616 * Return credentials of the door caller (if any) for this invocation 1617 */ 1618 int 1619 door_ucred(struct ucred_s *uch) 1620 { 1621 kthread_t *caller; 1622 door_server_t *st; 1623 door_client_t *ct; 1624 struct proc *p; 1625 struct ucred_s *res; 1626 int err; 1627 1628 mutex_enter(&door_knob); 1629 if ((st = door_my_server(0)) == NULL || 1630 (caller = st->d_caller) == NULL) { 1631 mutex_exit(&door_knob); 1632 return (set_errno(EINVAL)); 1633 } 1634 1635 ASSERT(caller->t_door != NULL); 1636 ct = DOOR_CLIENT(caller->t_door); 1637 1638 /* Prevent caller from exiting while we examine the cred */ 1639 DOOR_T_HOLD(ct); 1640 mutex_exit(&door_knob); 1641 1642 /* Get the credentials of the calling process */ 1643 p = ttoproc(caller); 1644 1645 res = pgetucred(p); 1646 1647 mutex_enter(&door_knob); 1648 DOOR_T_RELEASE(ct); 1649 mutex_exit(&door_knob); 1650 1651 err = copyout(res, uch, res->uc_size); 1652 1653 kmem_free(res, res->uc_size); 1654 1655 if (err != 0) 1656 return (set_errno(EFAULT)); 1657 1658 return (0); 1659 } 1660 1661 /* 1662 * Bind the current lwp to the server thread pool associated with 'did' 1663 */ 1664 int 1665 door_bind(int did) 1666 { 1667 door_node_t *dp; 1668 door_server_t *st; 1669 1670 if ((dp = door_lookup(did, NULL)) == NULL) { 1671 /* Not a door */ 1672 return (set_errno(EBADF)); 1673 } 1674 1675 /* 1676 * Can't bind to a non-private door, and can't bind to a door 1677 * served by another process. 1678 */ 1679 if ((dp->door_flags & DOOR_PRIVATE) == 0 || 1680 dp->door_target != curproc) { 1681 releasef(did); 1682 return (set_errno(EINVAL)); 1683 } 1684 1685 st = door_my_server(1); 1686 if (st->d_pool) 1687 door_unbind_thread(st->d_pool); 1688 st->d_pool = dp; 1689 st->d_invbound = 0; 1690 door_bind_thread(dp); 1691 releasef(did); 1692 1693 return (0); 1694 } 1695 1696 /* 1697 * Unbind the current lwp from it's server thread pool 1698 */ 1699 int 1700 door_unbind(void) 1701 { 1702 door_server_t *st; 1703 1704 if ((st = door_my_server(0)) == NULL) 1705 return (set_errno(EBADF)); 1706 1707 if (st->d_invbound) { 1708 ASSERT(st->d_pool == NULL); 1709 st->d_invbound = 0; 1710 return (0); 1711 } 1712 if (st->d_pool == NULL) 1713 return (set_errno(EBADF)); 1714 door_unbind_thread(st->d_pool); 1715 st->d_pool = NULL; 1716 return (0); 1717 } 1718 1719 /* 1720 * Create a descriptor for the associated file and fill in the 1721 * attributes associated with it. 1722 * 1723 * Return 0 for success, -1 otherwise; 1724 */ 1725 int 1726 door_insert(struct file *fp, door_desc_t *dp) 1727 { 1728 struct vnode *vp; 1729 int fd; 1730 door_attr_t attributes = DOOR_DESCRIPTOR; 1731 1732 ASSERT(MUTEX_NOT_HELD(&door_knob)); 1733 if ((fd = ufalloc(0)) == -1) 1734 return (-1); 1735 setf(fd, fp); 1736 dp->d_data.d_desc.d_descriptor = fd; 1737 1738 /* Fill in the attributes */ 1739 if (VOP_REALVP(fp->f_vnode, &vp, NULL)) 1740 vp = fp->f_vnode; 1741 if (vp && vp->v_type == VDOOR) { 1742 if (VTOD(vp)->door_target == curproc) 1743 attributes |= DOOR_LOCAL; 1744 attributes |= VTOD(vp)->door_flags & DOOR_ATTR_MASK; 1745 dp->d_data.d_desc.d_id = VTOD(vp)->door_index; 1746 } 1747 dp->d_attributes = attributes; 1748 return (0); 1749 } 1750 1751 /* 1752 * Return an available thread for this server. A NULL return value indicates 1753 * that either: 1754 * The door has been revoked, or 1755 * a signal was received. 1756 * The two conditions can be differentiated using DOOR_INVALID(dp). 1757 */ 1758 static kthread_t * 1759 door_get_server(door_node_t *dp) 1760 { 1761 kthread_t **ktp; 1762 kthread_t *server_t; 1763 door_pool_t *pool; 1764 door_server_t *st; 1765 int signalled; 1766 1767 disp_lock_t *tlp; 1768 cpu_t *cp; 1769 1770 ASSERT(MUTEX_HELD(&door_knob)); 1771 1772 if (dp->door_flags & DOOR_PRIVATE) 1773 pool = &dp->door_servers; 1774 else 1775 pool = &dp->door_target->p_server_threads; 1776 1777 for (;;) { 1778 /* 1779 * We search the thread pool, looking for a server thread 1780 * ready to take an invocation (i.e. one which is still 1781 * sleeping on a shuttle object). If none are available, 1782 * we sleep on the pool's CV, and will be signaled when a 1783 * thread is added to the pool. 1784 * 1785 * This relies on the fact that once a thread in the thread 1786 * pool wakes up, it *must* remove and add itself to the pool 1787 * before it can receive door calls. 1788 */ 1789 if (DOOR_INVALID(dp)) 1790 return (NULL); /* Target has become invalid */ 1791 1792 for (ktp = &pool->dp_threads; 1793 (server_t = *ktp) != NULL; 1794 ktp = &st->d_servers) { 1795 st = DOOR_SERVER(server_t->t_door); 1796 1797 thread_lock(server_t); 1798 if (server_t->t_state == TS_SLEEP && 1799 SOBJ_TYPE(server_t->t_sobj_ops) == SOBJ_SHUTTLE) 1800 break; 1801 thread_unlock(server_t); 1802 } 1803 if (server_t != NULL) 1804 break; /* we've got a live one! */ 1805 1806 if (!cv_wait_sig_swap_core(&pool->dp_cv, &door_knob, 1807 &signalled)) { 1808 /* 1809 * If we were signaled and the door is still 1810 * valid, pass the signal on to another waiter. 1811 */ 1812 if (signalled && !DOOR_INVALID(dp)) 1813 cv_signal(&pool->dp_cv); 1814 return (NULL); /* Got a signal */ 1815 } 1816 } 1817 1818 /* 1819 * We've got a thread_lock()ed thread which is still on the 1820 * shuttle. Take it off the list of available server threads 1821 * and mark it as ONPROC. We are committed to resuming this 1822 * thread now. 1823 */ 1824 tlp = server_t->t_lockp; 1825 cp = CPU; 1826 1827 *ktp = st->d_servers; 1828 st->d_servers = NULL; 1829 /* 1830 * Setting t_disp_queue prevents erroneous preemptions 1831 * if this thread is still in execution on another processor 1832 */ 1833 server_t->t_disp_queue = cp->cpu_disp; 1834 CL_ACTIVE(server_t); 1835 /* 1836 * We are calling thread_onproc() instead of 1837 * THREAD_ONPROC() because compiler can reorder 1838 * the two stores of t_state and t_lockp in 1839 * THREAD_ONPROC(). 1840 */ 1841 thread_onproc(server_t, cp); 1842 disp_lock_exit(tlp); 1843 return (server_t); 1844 } 1845 1846 /* 1847 * Put a server thread back in the pool. 1848 */ 1849 static void 1850 door_release_server(door_node_t *dp, kthread_t *t) 1851 { 1852 door_server_t *st = DOOR_SERVER(t->t_door); 1853 door_pool_t *pool; 1854 1855 ASSERT(MUTEX_HELD(&door_knob)); 1856 st->d_active = NULL; 1857 st->d_caller = NULL; 1858 st->d_layout_done = 0; 1859 if (dp && (dp->door_flags & DOOR_PRIVATE)) { 1860 ASSERT(dp->door_target == NULL || 1861 dp->door_target == ttoproc(t)); 1862 pool = &dp->door_servers; 1863 } else { 1864 pool = &ttoproc(t)->p_server_threads; 1865 } 1866 1867 st->d_servers = pool->dp_threads; 1868 pool->dp_threads = t; 1869 1870 /* If someone is waiting for a server thread, wake him up */ 1871 cv_signal(&pool->dp_cv); 1872 } 1873 1874 /* 1875 * Remove a server thread from the pool if present. 1876 */ 1877 static void 1878 door_server_exit(proc_t *p, kthread_t *t) 1879 { 1880 door_pool_t *pool; 1881 kthread_t **next; 1882 door_server_t *st = DOOR_SERVER(t->t_door); 1883 1884 ASSERT(MUTEX_HELD(&door_knob)); 1885 if (st->d_pool != NULL) { 1886 ASSERT(st->d_pool->door_flags & DOOR_PRIVATE); 1887 pool = &st->d_pool->door_servers; 1888 } else { 1889 pool = &p->p_server_threads; 1890 } 1891 1892 next = &pool->dp_threads; 1893 while (*next != NULL) { 1894 if (*next == t) { 1895 *next = DOOR_SERVER(t->t_door)->d_servers; 1896 return; 1897 } 1898 next = &(DOOR_SERVER((*next)->t_door)->d_servers); 1899 } 1900 } 1901 1902 /* 1903 * Lookup the door descriptor. Caller must call releasef when finished 1904 * with associated door. 1905 */ 1906 static door_node_t * 1907 door_lookup(int did, file_t **fpp) 1908 { 1909 vnode_t *vp; 1910 file_t *fp; 1911 1912 ASSERT(MUTEX_NOT_HELD(&door_knob)); 1913 if ((fp = getf(did)) == NULL) 1914 return (NULL); 1915 /* 1916 * Use the underlying vnode (we may be namefs mounted) 1917 */ 1918 if (VOP_REALVP(fp->f_vnode, &vp, NULL)) 1919 vp = fp->f_vnode; 1920 1921 if (vp == NULL || vp->v_type != VDOOR) { 1922 releasef(did); 1923 return (NULL); 1924 } 1925 1926 if (fpp) 1927 *fpp = fp; 1928 1929 return (VTOD(vp)); 1930 } 1931 1932 /* 1933 * The current thread is exiting, so clean up any pending 1934 * invocation details 1935 */ 1936 void 1937 door_slam(void) 1938 { 1939 door_node_t *dp; 1940 door_data_t *dt; 1941 door_client_t *ct; 1942 door_server_t *st; 1943 1944 /* 1945 * If we are an active door server, notify our 1946 * client that we are exiting and revoke our door. 1947 */ 1948 if ((dt = door_my_data(0)) == NULL) 1949 return; 1950 ct = DOOR_CLIENT(dt); 1951 st = DOOR_SERVER(dt); 1952 1953 mutex_enter(&door_knob); 1954 for (;;) { 1955 if (DOOR_T_HELD(ct)) 1956 cv_wait(&ct->d_cv, &door_knob); 1957 else if (DOOR_T_HELD(st)) 1958 cv_wait(&st->d_cv, &door_knob); 1959 else 1960 break; /* neither flag is set */ 1961 } 1962 curthread->t_door = NULL; 1963 if ((dp = st->d_active) != NULL) { 1964 kthread_t *t = st->d_caller; 1965 proc_t *p = curproc; 1966 1967 /* Revoke our door if the process is exiting */ 1968 if (dp->door_target == p && (p->p_flag & SEXITING)) { 1969 door_list_delete(dp); 1970 dp->door_target = NULL; 1971 dp->door_flags |= DOOR_REVOKED; 1972 if (dp->door_flags & DOOR_PRIVATE) 1973 cv_broadcast(&dp->door_servers.dp_cv); 1974 else 1975 cv_broadcast(&p->p_server_threads.dp_cv); 1976 } 1977 1978 if (t != NULL) { 1979 /* 1980 * Let the caller know we are gone 1981 */ 1982 DOOR_CLIENT(t->t_door)->d_error = DOOR_EXIT; 1983 thread_lock(t); 1984 if (t->t_state == TS_SLEEP && 1985 SOBJ_TYPE(t->t_sobj_ops) == SOBJ_SHUTTLE) 1986 setrun_locked(t); 1987 thread_unlock(t); 1988 } 1989 } 1990 mutex_exit(&door_knob); 1991 if (st->d_pool) 1992 door_unbind_thread(st->d_pool); /* Implicit door_unbind */ 1993 kmem_free(dt, sizeof (door_data_t)); 1994 } 1995 1996 /* 1997 * Set DOOR_REVOKED for all doors of the current process. This is called 1998 * on exit before all lwp's are being terminated so that door calls will 1999 * return with an error. 2000 */ 2001 void 2002 door_revoke_all() 2003 { 2004 door_node_t *dp; 2005 proc_t *p = ttoproc(curthread); 2006 2007 mutex_enter(&door_knob); 2008 for (dp = p->p_door_list; dp != NULL; dp = dp->door_list) { 2009 ASSERT(dp->door_target == p); 2010 dp->door_flags |= DOOR_REVOKED; 2011 if (dp->door_flags & DOOR_PRIVATE) 2012 cv_broadcast(&dp->door_servers.dp_cv); 2013 } 2014 cv_broadcast(&p->p_server_threads.dp_cv); 2015 mutex_exit(&door_knob); 2016 } 2017 2018 /* 2019 * The process is exiting, and all doors it created need to be revoked. 2020 */ 2021 void 2022 door_exit(void) 2023 { 2024 door_node_t *dp; 2025 proc_t *p = ttoproc(curthread); 2026 2027 ASSERT(p->p_lwpcnt == 1); 2028 /* 2029 * Walk the list of active doors created by this process and 2030 * revoke them all. 2031 */ 2032 mutex_enter(&door_knob); 2033 for (dp = p->p_door_list; dp != NULL; dp = dp->door_list) { 2034 dp->door_target = NULL; 2035 dp->door_flags |= DOOR_REVOKED; 2036 if (dp->door_flags & DOOR_PRIVATE) 2037 cv_broadcast(&dp->door_servers.dp_cv); 2038 } 2039 cv_broadcast(&p->p_server_threads.dp_cv); 2040 /* Clear the list */ 2041 p->p_door_list = NULL; 2042 2043 /* Clean up the unref list */ 2044 while ((dp = p->p_unref_list) != NULL) { 2045 p->p_unref_list = dp->door_ulist; 2046 dp->door_ulist = NULL; 2047 mutex_exit(&door_knob); 2048 VN_RELE(DTOV(dp)); 2049 mutex_enter(&door_knob); 2050 } 2051 mutex_exit(&door_knob); 2052 } 2053 2054 2055 /* 2056 * The process is executing forkall(), and we need to flag threads that 2057 * are bound to a door in the child. This will make the child threads 2058 * return an error to door_return unless they call door_unbind first. 2059 */ 2060 void 2061 door_fork(kthread_t *parent, kthread_t *child) 2062 { 2063 door_data_t *pt = parent->t_door; 2064 door_server_t *st = DOOR_SERVER(pt); 2065 door_data_t *dt; 2066 2067 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2068 if (pt != NULL && (st->d_pool != NULL || st->d_invbound)) { 2069 /* parent thread is bound to a door */ 2070 dt = child->t_door = 2071 kmem_zalloc(sizeof (door_data_t), KM_SLEEP); 2072 DOOR_SERVER(dt)->d_invbound = 1; 2073 } 2074 } 2075 2076 /* 2077 * Deliver queued unrefs to appropriate door server. 2078 */ 2079 static int 2080 door_unref(void) 2081 { 2082 door_node_t *dp; 2083 static door_arg_t unref_args = { DOOR_UNREF_DATA, 0, 0, 0, 0, 0 }; 2084 proc_t *p = ttoproc(curthread); 2085 2086 /* make sure there's only one unref thread per process */ 2087 mutex_enter(&door_knob); 2088 if (p->p_unref_thread) { 2089 mutex_exit(&door_knob); 2090 return (set_errno(EALREADY)); 2091 } 2092 p->p_unref_thread = 1; 2093 mutex_exit(&door_knob); 2094 2095 (void) door_my_data(1); /* create info, if necessary */ 2096 2097 for (;;) { 2098 mutex_enter(&door_knob); 2099 2100 /* Grab a queued request */ 2101 while ((dp = p->p_unref_list) == NULL) { 2102 if (!cv_wait_sig(&p->p_unref_cv, &door_knob)) { 2103 /* 2104 * Interrupted. 2105 * Return so we can finish forkall() or exit(). 2106 */ 2107 p->p_unref_thread = 0; 2108 mutex_exit(&door_knob); 2109 return (set_errno(EINTR)); 2110 } 2111 } 2112 p->p_unref_list = dp->door_ulist; 2113 dp->door_ulist = NULL; 2114 dp->door_flags |= DOOR_UNREF_ACTIVE; 2115 mutex_exit(&door_knob); 2116 2117 (void) door_upcall(DTOV(dp), &unref_args); 2118 2119 mutex_enter(&door_knob); 2120 ASSERT(dp->door_flags & DOOR_UNREF_ACTIVE); 2121 dp->door_flags &= ~DOOR_UNREF_ACTIVE; 2122 mutex_exit(&door_knob); 2123 VN_RELE(DTOV(dp)); 2124 } 2125 } 2126 2127 2128 /* 2129 * Deliver queued unrefs to kernel door server. 2130 */ 2131 /* ARGSUSED */ 2132 static void 2133 door_unref_kernel(caddr_t arg) 2134 { 2135 door_node_t *dp; 2136 static door_arg_t unref_args = { DOOR_UNREF_DATA, 0, 0, 0, 0, 0 }; 2137 proc_t *p = ttoproc(curthread); 2138 callb_cpr_t cprinfo; 2139 2140 /* should only be one of these */ 2141 mutex_enter(&door_knob); 2142 if (p->p_unref_thread) { 2143 mutex_exit(&door_knob); 2144 return; 2145 } 2146 p->p_unref_thread = 1; 2147 mutex_exit(&door_knob); 2148 2149 (void) door_my_data(1); /* make sure we have a door_data_t */ 2150 2151 CALLB_CPR_INIT(&cprinfo, &door_knob, callb_generic_cpr, "door_unref"); 2152 for (;;) { 2153 mutex_enter(&door_knob); 2154 /* Grab a queued request */ 2155 while ((dp = p->p_unref_list) == NULL) { 2156 CALLB_CPR_SAFE_BEGIN(&cprinfo); 2157 cv_wait(&p->p_unref_cv, &door_knob); 2158 CALLB_CPR_SAFE_END(&cprinfo, &door_knob); 2159 } 2160 p->p_unref_list = dp->door_ulist; 2161 dp->door_ulist = NULL; 2162 dp->door_flags |= DOOR_UNREF_ACTIVE; 2163 mutex_exit(&door_knob); 2164 2165 (*(dp->door_pc))(dp->door_data, &unref_args, NULL, NULL, NULL); 2166 2167 mutex_enter(&door_knob); 2168 ASSERT(dp->door_flags & DOOR_UNREF_ACTIVE); 2169 dp->door_flags &= ~DOOR_UNREF_ACTIVE; 2170 mutex_exit(&door_knob); 2171 VN_RELE(DTOV(dp)); 2172 } 2173 } 2174 2175 2176 /* 2177 * Queue an unref invocation for processing for the current process 2178 * The door may or may not be revoked at this point. 2179 */ 2180 void 2181 door_deliver_unref(door_node_t *d) 2182 { 2183 struct proc *server = d->door_target; 2184 2185 ASSERT(MUTEX_HELD(&door_knob)); 2186 ASSERT(d->door_active == 0); 2187 2188 if (server == NULL) 2189 return; 2190 /* 2191 * Create a lwp to deliver unref calls if one isn't already running. 2192 * 2193 * A separate thread is used to deliver unrefs since the current 2194 * thread may be holding resources (e.g. locks) in user land that 2195 * may be needed by the unref processing. This would cause a 2196 * deadlock. 2197 */ 2198 if (d->door_flags & DOOR_UNREF_MULTI) { 2199 /* multiple unrefs */ 2200 d->door_flags &= ~DOOR_DELAY; 2201 } else { 2202 /* Only 1 unref per door */ 2203 d->door_flags &= ~(DOOR_UNREF|DOOR_DELAY); 2204 } 2205 mutex_exit(&door_knob); 2206 2207 /* 2208 * Need to bump the vnode count before putting the door on the 2209 * list so it doesn't get prematurely released by door_unref. 2210 */ 2211 VN_HOLD(DTOV(d)); 2212 2213 mutex_enter(&door_knob); 2214 /* is this door already on the unref list? */ 2215 if (d->door_flags & DOOR_UNREF_MULTI) { 2216 door_node_t *dp; 2217 for (dp = server->p_unref_list; dp != NULL; 2218 dp = dp->door_ulist) { 2219 if (d == dp) { 2220 /* already there, don't need to add another */ 2221 mutex_exit(&door_knob); 2222 VN_RELE(DTOV(d)); 2223 mutex_enter(&door_knob); 2224 return; 2225 } 2226 } 2227 } 2228 ASSERT(d->door_ulist == NULL); 2229 d->door_ulist = server->p_unref_list; 2230 server->p_unref_list = d; 2231 cv_broadcast(&server->p_unref_cv); 2232 } 2233 2234 /* 2235 * The callers buffer isn't big enough for all of the data/fd's. Allocate 2236 * space in the callers address space for the results and copy the data 2237 * there. 2238 * 2239 * For EOVERFLOW, we must clean up the server's door descriptors. 2240 */ 2241 static int 2242 door_overflow( 2243 kthread_t *caller, 2244 caddr_t data_ptr, /* data location */ 2245 size_t data_size, /* data size */ 2246 door_desc_t *desc_ptr, /* descriptor location */ 2247 uint_t desc_num) /* descriptor size */ 2248 { 2249 proc_t *callerp = ttoproc(caller); 2250 struct as *as = callerp->p_as; 2251 door_client_t *ct = DOOR_CLIENT(caller->t_door); 2252 caddr_t addr; /* Resulting address in target */ 2253 size_t rlen; /* Rounded len */ 2254 size_t len; 2255 uint_t i; 2256 size_t ds = desc_num * sizeof (door_desc_t); 2257 2258 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2259 ASSERT(DOOR_T_HELD(ct) || ct->d_kernel); 2260 2261 /* Do initial overflow check */ 2262 if (!ufcanalloc(callerp, desc_num)) 2263 return (EMFILE); 2264 2265 /* 2266 * Allocate space for this stuff in the callers address space 2267 */ 2268 rlen = roundup(data_size + ds, PAGESIZE); 2269 as_rangelock(as); 2270 map_addr_proc(&addr, rlen, 0, 1, as->a_userlimit, ttoproc(caller), 0); 2271 if (addr == NULL || 2272 as_map(as, addr, rlen, segvn_create, zfod_argsp) != 0) { 2273 /* No virtual memory available, or anon mapping failed */ 2274 as_rangeunlock(as); 2275 if (!ct->d_kernel && desc_num > 0) { 2276 int error = door_release_fds(desc_ptr, desc_num); 2277 if (error) 2278 return (error); 2279 } 2280 return (EOVERFLOW); 2281 } 2282 as_rangeunlock(as); 2283 2284 if (ct->d_kernel) 2285 goto out; 2286 2287 if (data_size != 0) { 2288 caddr_t src = data_ptr; 2289 caddr_t saddr = addr; 2290 2291 /* Copy any data */ 2292 len = data_size; 2293 while (len != 0) { 2294 int amount; 2295 int error; 2296 2297 amount = len > PAGESIZE ? PAGESIZE : len; 2298 if ((error = door_copy(as, src, saddr, amount)) != 0) { 2299 (void) as_unmap(as, addr, rlen); 2300 return (error); 2301 } 2302 saddr += amount; 2303 src += amount; 2304 len -= amount; 2305 } 2306 } 2307 /* Copy any fd's */ 2308 if (desc_num != 0) { 2309 door_desc_t *didpp, *start; 2310 struct file **fpp; 2311 int fpp_size; 2312 2313 start = didpp = kmem_alloc(ds, KM_SLEEP); 2314 if (copyin(desc_ptr, didpp, ds)) { 2315 kmem_free(start, ds); 2316 (void) as_unmap(as, addr, rlen); 2317 return (EFAULT); 2318 } 2319 2320 fpp_size = desc_num * sizeof (struct file *); 2321 if (fpp_size > ct->d_fpp_size) { 2322 /* make more space */ 2323 if (ct->d_fpp_size) 2324 kmem_free(ct->d_fpp, ct->d_fpp_size); 2325 ct->d_fpp_size = fpp_size; 2326 ct->d_fpp = kmem_alloc(ct->d_fpp_size, KM_SLEEP); 2327 } 2328 fpp = ct->d_fpp; 2329 2330 for (i = 0; i < desc_num; i++) { 2331 struct file *fp; 2332 int fd = didpp->d_data.d_desc.d_descriptor; 2333 2334 if (!(didpp->d_attributes & DOOR_DESCRIPTOR) || 2335 (fp = getf(fd)) == NULL) { 2336 /* close translated references */ 2337 door_fp_close(ct->d_fpp, fpp - ct->d_fpp); 2338 /* close untranslated references */ 2339 door_fd_rele(didpp, desc_num - i, 0); 2340 kmem_free(start, ds); 2341 (void) as_unmap(as, addr, rlen); 2342 return (EINVAL); 2343 } 2344 mutex_enter(&fp->f_tlock); 2345 fp->f_count++; 2346 mutex_exit(&fp->f_tlock); 2347 2348 *fpp = fp; 2349 releasef(fd); 2350 2351 if (didpp->d_attributes & DOOR_RELEASE) { 2352 /* release passed reference */ 2353 (void) closeandsetf(fd, NULL); 2354 } 2355 2356 fpp++; didpp++; 2357 } 2358 kmem_free(start, ds); 2359 } 2360 2361 out: 2362 ct->d_overflow = 1; 2363 ct->d_args.rbuf = addr; 2364 ct->d_args.rsize = rlen; 2365 return (0); 2366 } 2367 2368 /* 2369 * Transfer arguments from the client to the server. 2370 */ 2371 static int 2372 door_args(kthread_t *server, int is_private) 2373 { 2374 door_server_t *st = DOOR_SERVER(server->t_door); 2375 door_client_t *ct = DOOR_CLIENT(curthread->t_door); 2376 uint_t ndid; 2377 size_t dsize; 2378 int error; 2379 2380 ASSERT(DOOR_T_HELD(st)); 2381 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2382 2383 ndid = ct->d_args.desc_num; 2384 if (ndid > door_max_desc) 2385 return (E2BIG); 2386 2387 /* 2388 * Get the stack layout, and fail now if it won't fit. 2389 */ 2390 error = door_layout(server, ct->d_args.data_size, ndid, is_private); 2391 if (error != 0) 2392 return (error); 2393 2394 dsize = ndid * sizeof (door_desc_t); 2395 if (ct->d_args.data_size != 0) { 2396 if (ct->d_args.data_size <= door_max_arg) { 2397 /* 2398 * Use a 2 copy method for small amounts of data 2399 * 2400 * Allocate a little more than we need for the 2401 * args, in the hope that the results will fit 2402 * without having to reallocate a buffer 2403 */ 2404 ASSERT(ct->d_buf == NULL); 2405 ct->d_bufsize = roundup(ct->d_args.data_size, 2406 DOOR_ROUND); 2407 ct->d_buf = kmem_alloc(ct->d_bufsize, KM_SLEEP); 2408 if (copyin(ct->d_args.data_ptr, 2409 ct->d_buf, ct->d_args.data_size) != 0) { 2410 kmem_free(ct->d_buf, ct->d_bufsize); 2411 ct->d_buf = NULL; 2412 ct->d_bufsize = 0; 2413 return (EFAULT); 2414 } 2415 } else { 2416 struct as *as; 2417 caddr_t src; 2418 caddr_t dest; 2419 size_t len = ct->d_args.data_size; 2420 uintptr_t base; 2421 2422 /* 2423 * Use a 1 copy method 2424 */ 2425 as = ttoproc(server)->p_as; 2426 src = ct->d_args.data_ptr; 2427 2428 dest = st->d_layout.dl_datap; 2429 base = (uintptr_t)dest; 2430 2431 /* 2432 * Copy data directly into server. We proceed 2433 * downward from the top of the stack, to mimic 2434 * normal stack usage. This allows the guard page 2435 * to stop us before we corrupt anything. 2436 */ 2437 while (len != 0) { 2438 uintptr_t start; 2439 uintptr_t end; 2440 uintptr_t offset; 2441 size_t amount; 2442 2443 /* 2444 * Locate the next part to copy. 2445 */ 2446 end = base + len; 2447 start = P2ALIGN(end - 1, PAGESIZE); 2448 2449 /* 2450 * if we are on the final (first) page, fix 2451 * up the start position. 2452 */ 2453 if (P2ALIGN(base, PAGESIZE) == start) 2454 start = base; 2455 2456 offset = start - base; /* the copy offset */ 2457 amount = end - start; /* # bytes to copy */ 2458 2459 ASSERT(amount > 0 && amount <= len && 2460 amount <= PAGESIZE); 2461 2462 error = door_copy(as, src + offset, 2463 dest + offset, amount); 2464 if (error != 0) 2465 return (error); 2466 len -= amount; 2467 } 2468 } 2469 } 2470 /* 2471 * Copyin the door args and translate them into files 2472 */ 2473 if (ndid != 0) { 2474 door_desc_t *didpp; 2475 door_desc_t *start; 2476 struct file **fpp; 2477 2478 start = didpp = kmem_alloc(dsize, KM_SLEEP); 2479 2480 if (copyin(ct->d_args.desc_ptr, didpp, dsize)) { 2481 kmem_free(start, dsize); 2482 return (EFAULT); 2483 } 2484 ct->d_fpp_size = ndid * sizeof (struct file *); 2485 ct->d_fpp = kmem_alloc(ct->d_fpp_size, KM_SLEEP); 2486 fpp = ct->d_fpp; 2487 while (ndid--) { 2488 struct file *fp; 2489 int fd = didpp->d_data.d_desc.d_descriptor; 2490 2491 /* We only understand file descriptors as passed objs */ 2492 if (!(didpp->d_attributes & DOOR_DESCRIPTOR) || 2493 (fp = getf(fd)) == NULL) { 2494 /* close translated references */ 2495 door_fp_close(ct->d_fpp, fpp - ct->d_fpp); 2496 /* close untranslated references */ 2497 door_fd_rele(didpp, ndid + 1, 0); 2498 kmem_free(start, dsize); 2499 kmem_free(ct->d_fpp, ct->d_fpp_size); 2500 ct->d_fpp = NULL; 2501 ct->d_fpp_size = 0; 2502 return (EINVAL); 2503 } 2504 /* Hold the fp */ 2505 mutex_enter(&fp->f_tlock); 2506 fp->f_count++; 2507 mutex_exit(&fp->f_tlock); 2508 2509 *fpp = fp; 2510 releasef(fd); 2511 2512 if (didpp->d_attributes & DOOR_RELEASE) { 2513 /* release passed reference */ 2514 (void) closeandsetf(fd, NULL); 2515 } 2516 2517 fpp++; didpp++; 2518 } 2519 kmem_free(start, dsize); 2520 } 2521 return (0); 2522 } 2523 2524 /* 2525 * Transfer arguments from a user client to a kernel server. This copies in 2526 * descriptors and translates them into door handles. It doesn't touch the 2527 * other data, letting the kernel server deal with that (to avoid needing 2528 * to copy the data twice). 2529 */ 2530 static int 2531 door_translate_in(void) 2532 { 2533 door_client_t *ct = DOOR_CLIENT(curthread->t_door); 2534 uint_t ndid; 2535 2536 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2537 ndid = ct->d_args.desc_num; 2538 if (ndid > door_max_desc) 2539 return (E2BIG); 2540 /* 2541 * Copyin the door args and translate them into door handles. 2542 */ 2543 if (ndid != 0) { 2544 door_desc_t *didpp; 2545 door_desc_t *start; 2546 size_t dsize = ndid * sizeof (door_desc_t); 2547 struct file *fp; 2548 2549 start = didpp = kmem_alloc(dsize, KM_SLEEP); 2550 2551 if (copyin(ct->d_args.desc_ptr, didpp, dsize)) { 2552 kmem_free(start, dsize); 2553 return (EFAULT); 2554 } 2555 while (ndid--) { 2556 vnode_t *vp; 2557 int fd = didpp->d_data.d_desc.d_descriptor; 2558 2559 /* 2560 * We only understand file descriptors as passed objs 2561 */ 2562 if ((didpp->d_attributes & DOOR_DESCRIPTOR) && 2563 (fp = getf(fd)) != NULL) { 2564 didpp->d_data.d_handle = FTODH(fp); 2565 /* Hold the door */ 2566 door_ki_hold(didpp->d_data.d_handle); 2567 2568 releasef(fd); 2569 2570 if (didpp->d_attributes & DOOR_RELEASE) { 2571 /* release passed reference */ 2572 (void) closeandsetf(fd, NULL); 2573 } 2574 2575 if (VOP_REALVP(fp->f_vnode, &vp, NULL)) 2576 vp = fp->f_vnode; 2577 2578 /* Set attributes */ 2579 didpp->d_attributes = DOOR_HANDLE | 2580 (VTOD(vp)->door_flags & DOOR_ATTR_MASK); 2581 } else { 2582 /* close translated references */ 2583 door_fd_close(start, didpp - start); 2584 /* close untranslated references */ 2585 door_fd_rele(didpp, ndid + 1, 0); 2586 kmem_free(start, dsize); 2587 return (EINVAL); 2588 } 2589 didpp++; 2590 } 2591 ct->d_args.desc_ptr = start; 2592 } 2593 return (0); 2594 } 2595 2596 /* 2597 * Translate door arguments from kernel to user. This copies the passed 2598 * door handles. It doesn't touch other data. It is used by door_upcall, 2599 * and for data returned by a door_call to a kernel server. 2600 */ 2601 static int 2602 door_translate_out(void) 2603 { 2604 door_client_t *ct = DOOR_CLIENT(curthread->t_door); 2605 uint_t ndid; 2606 2607 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2608 ndid = ct->d_args.desc_num; 2609 if (ndid > door_max_desc) { 2610 door_fd_rele(ct->d_args.desc_ptr, ndid, 1); 2611 return (E2BIG); 2612 } 2613 /* 2614 * Translate the door args into files 2615 */ 2616 if (ndid != 0) { 2617 door_desc_t *didpp = ct->d_args.desc_ptr; 2618 struct file **fpp; 2619 2620 ct->d_fpp_size = ndid * sizeof (struct file *); 2621 fpp = ct->d_fpp = kmem_alloc(ct->d_fpp_size, KM_SLEEP); 2622 while (ndid--) { 2623 struct file *fp = NULL; 2624 int fd = -1; 2625 2626 /* 2627 * We understand file descriptors and door 2628 * handles as passed objs. 2629 */ 2630 if (didpp->d_attributes & DOOR_DESCRIPTOR) { 2631 fd = didpp->d_data.d_desc.d_descriptor; 2632 fp = getf(fd); 2633 } else if (didpp->d_attributes & DOOR_HANDLE) 2634 fp = DHTOF(didpp->d_data.d_handle); 2635 if (fp != NULL) { 2636 /* Hold the fp */ 2637 mutex_enter(&fp->f_tlock); 2638 fp->f_count++; 2639 mutex_exit(&fp->f_tlock); 2640 2641 *fpp = fp; 2642 if (didpp->d_attributes & DOOR_DESCRIPTOR) 2643 releasef(fd); 2644 if (didpp->d_attributes & DOOR_RELEASE) { 2645 /* release passed reference */ 2646 if (fd >= 0) 2647 (void) closeandsetf(fd, NULL); 2648 else 2649 (void) closef(fp); 2650 } 2651 } else { 2652 /* close translated references */ 2653 door_fp_close(ct->d_fpp, fpp - ct->d_fpp); 2654 /* close untranslated references */ 2655 door_fd_rele(didpp, ndid + 1, 1); 2656 kmem_free(ct->d_fpp, ct->d_fpp_size); 2657 ct->d_fpp = NULL; 2658 ct->d_fpp_size = 0; 2659 return (EINVAL); 2660 } 2661 fpp++; didpp++; 2662 } 2663 } 2664 return (0); 2665 } 2666 2667 /* 2668 * Move the results from the server to the client 2669 */ 2670 static int 2671 door_results(kthread_t *caller, caddr_t data_ptr, size_t data_size, 2672 door_desc_t *desc_ptr, uint_t desc_num) 2673 { 2674 door_client_t *ct = DOOR_CLIENT(caller->t_door); 2675 size_t dsize; 2676 size_t rlen; 2677 size_t result_size; 2678 2679 ASSERT(DOOR_T_HELD(ct)); 2680 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2681 2682 if (ct->d_noresults) 2683 return (E2BIG); /* No results expected */ 2684 2685 if (desc_num > door_max_desc) 2686 return (E2BIG); /* Too many descriptors */ 2687 2688 dsize = desc_num * sizeof (door_desc_t); 2689 /* 2690 * Check if the results are bigger than the clients buffer 2691 */ 2692 if (dsize) 2693 rlen = roundup(data_size, sizeof (door_desc_t)); 2694 else 2695 rlen = data_size; 2696 if ((result_size = rlen + dsize) == 0) 2697 return (0); 2698 2699 if (ct->d_upcall) { 2700 /* 2701 * Handle upcalls 2702 */ 2703 if (ct->d_args.rbuf == NULL || ct->d_args.rsize < result_size) { 2704 /* 2705 * If there's no return buffer or the buffer is too 2706 * small, allocate a new one. The old buffer (if it 2707 * exists) will be freed by the upcall client. 2708 */ 2709 if (result_size > door_max_upcall_reply) 2710 return (E2BIG); 2711 ct->d_args.rsize = result_size; 2712 ct->d_args.rbuf = kmem_alloc(result_size, KM_SLEEP); 2713 } 2714 ct->d_args.data_ptr = ct->d_args.rbuf; 2715 if (data_size != 0 && 2716 copyin(data_ptr, ct->d_args.data_ptr, data_size) != 0) 2717 return (EFAULT); 2718 } else if (result_size > ct->d_args.rsize) { 2719 return (door_overflow(caller, data_ptr, data_size, 2720 desc_ptr, desc_num)); 2721 } else if (data_size != 0) { 2722 if (data_size <= door_max_arg) { 2723 /* 2724 * Use a 2 copy method for small amounts of data 2725 */ 2726 if (ct->d_buf == NULL) { 2727 ct->d_bufsize = data_size; 2728 ct->d_buf = kmem_alloc(ct->d_bufsize, KM_SLEEP); 2729 } else if (ct->d_bufsize < data_size) { 2730 kmem_free(ct->d_buf, ct->d_bufsize); 2731 ct->d_bufsize = data_size; 2732 ct->d_buf = kmem_alloc(ct->d_bufsize, KM_SLEEP); 2733 } 2734 if (copyin(data_ptr, ct->d_buf, data_size) != 0) 2735 return (EFAULT); 2736 } else { 2737 struct as *as = ttoproc(caller)->p_as; 2738 caddr_t dest = ct->d_args.rbuf; 2739 caddr_t src = data_ptr; 2740 size_t len = data_size; 2741 2742 /* Copy data directly into client */ 2743 while (len != 0) { 2744 uint_t amount; 2745 uint_t max; 2746 uint_t off; 2747 int error; 2748 2749 off = (uintptr_t)dest & PAGEOFFSET; 2750 if (off) 2751 max = PAGESIZE - off; 2752 else 2753 max = PAGESIZE; 2754 amount = len > max ? max : len; 2755 error = door_copy(as, src, dest, amount); 2756 if (error != 0) 2757 return (error); 2758 dest += amount; 2759 src += amount; 2760 len -= amount; 2761 } 2762 } 2763 } 2764 2765 /* 2766 * Copyin the returned door ids and translate them into door_node_t 2767 */ 2768 if (desc_num != 0) { 2769 door_desc_t *start; 2770 door_desc_t *didpp; 2771 struct file **fpp; 2772 size_t fpp_size; 2773 uint_t i; 2774 2775 /* First, check if we would overflow client */ 2776 if (!ufcanalloc(ttoproc(caller), desc_num)) 2777 return (EMFILE); 2778 2779 start = didpp = kmem_alloc(dsize, KM_SLEEP); 2780 if (copyin(desc_ptr, didpp, dsize)) { 2781 kmem_free(start, dsize); 2782 return (EFAULT); 2783 } 2784 fpp_size = desc_num * sizeof (struct file *); 2785 if (fpp_size > ct->d_fpp_size) { 2786 /* make more space */ 2787 if (ct->d_fpp_size) 2788 kmem_free(ct->d_fpp, ct->d_fpp_size); 2789 ct->d_fpp_size = fpp_size; 2790 ct->d_fpp = kmem_alloc(fpp_size, KM_SLEEP); 2791 } 2792 fpp = ct->d_fpp; 2793 2794 for (i = 0; i < desc_num; i++) { 2795 struct file *fp; 2796 int fd = didpp->d_data.d_desc.d_descriptor; 2797 2798 /* Only understand file descriptor results */ 2799 if (!(didpp->d_attributes & DOOR_DESCRIPTOR) || 2800 (fp = getf(fd)) == NULL) { 2801 /* close translated references */ 2802 door_fp_close(ct->d_fpp, fpp - ct->d_fpp); 2803 /* close untranslated references */ 2804 door_fd_rele(didpp, desc_num - i, 0); 2805 kmem_free(start, dsize); 2806 return (EINVAL); 2807 } 2808 2809 mutex_enter(&fp->f_tlock); 2810 fp->f_count++; 2811 mutex_exit(&fp->f_tlock); 2812 2813 *fpp = fp; 2814 releasef(fd); 2815 2816 if (didpp->d_attributes & DOOR_RELEASE) { 2817 /* release passed reference */ 2818 (void) closeandsetf(fd, NULL); 2819 } 2820 2821 fpp++; didpp++; 2822 } 2823 kmem_free(start, dsize); 2824 } 2825 return (0); 2826 } 2827 2828 /* 2829 * Close all the descriptors. 2830 */ 2831 static void 2832 door_fd_close(door_desc_t *d, uint_t n) 2833 { 2834 uint_t i; 2835 2836 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2837 for (i = 0; i < n; i++) { 2838 if (d->d_attributes & DOOR_DESCRIPTOR) { 2839 (void) closeandsetf( 2840 d->d_data.d_desc.d_descriptor, NULL); 2841 } else if (d->d_attributes & DOOR_HANDLE) { 2842 door_ki_rele(d->d_data.d_handle); 2843 } 2844 d++; 2845 } 2846 } 2847 2848 /* 2849 * Close descriptors that have the DOOR_RELEASE attribute set. 2850 */ 2851 void 2852 door_fd_rele(door_desc_t *d, uint_t n, int from_kernel) 2853 { 2854 uint_t i; 2855 2856 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2857 for (i = 0; i < n; i++) { 2858 if (d->d_attributes & DOOR_RELEASE) { 2859 if (d->d_attributes & DOOR_DESCRIPTOR) { 2860 (void) closeandsetf( 2861 d->d_data.d_desc.d_descriptor, NULL); 2862 } else if (from_kernel && 2863 (d->d_attributes & DOOR_HANDLE)) { 2864 door_ki_rele(d->d_data.d_handle); 2865 } 2866 } 2867 d++; 2868 } 2869 } 2870 2871 /* 2872 * Copy descriptors into the kernel so we can release any marked 2873 * DOOR_RELEASE. 2874 */ 2875 int 2876 door_release_fds(door_desc_t *desc_ptr, uint_t ndesc) 2877 { 2878 size_t dsize; 2879 door_desc_t *didpp; 2880 uint_t desc_num; 2881 2882 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2883 ASSERT(ndesc != 0); 2884 2885 desc_num = MIN(ndesc, door_max_desc); 2886 2887 dsize = desc_num * sizeof (door_desc_t); 2888 didpp = kmem_alloc(dsize, KM_SLEEP); 2889 2890 while (ndesc > 0) { 2891 uint_t count = MIN(ndesc, desc_num); 2892 2893 if (copyin(desc_ptr, didpp, count * sizeof (door_desc_t))) { 2894 kmem_free(didpp, dsize); 2895 return (EFAULT); 2896 } 2897 door_fd_rele(didpp, count, 0); 2898 2899 ndesc -= count; 2900 desc_ptr += count; 2901 } 2902 kmem_free(didpp, dsize); 2903 return (0); 2904 } 2905 2906 /* 2907 * Decrement ref count on all the files passed 2908 */ 2909 static void 2910 door_fp_close(struct file **fp, uint_t n) 2911 { 2912 uint_t i; 2913 2914 ASSERT(MUTEX_NOT_HELD(&door_knob)); 2915 2916 for (i = 0; i < n; i++) 2917 (void) closef(fp[i]); 2918 } 2919 2920 /* 2921 * Copy data from 'src' in current address space to 'dest' in 'as' for 'len' 2922 * bytes. 2923 * 2924 * Performs this using 1 mapin and 1 copy operation. 2925 * 2926 * We really should do more than 1 page at a time to improve 2927 * performance, but for now this is treated as an anomalous condition. 2928 */ 2929 static int 2930 door_copy(struct as *as, caddr_t src, caddr_t dest, uint_t len) 2931 { 2932 caddr_t kaddr; 2933 caddr_t rdest; 2934 uint_t off; 2935 page_t **pplist; 2936 page_t *pp = NULL; 2937 int error = 0; 2938 2939 ASSERT(len <= PAGESIZE); 2940 off = (uintptr_t)dest & PAGEOFFSET; /* offset within the page */ 2941 rdest = (caddr_t)((uintptr_t)dest & 2942 (uintptr_t)PAGEMASK); /* Page boundary */ 2943 ASSERT(off + len <= PAGESIZE); 2944 2945 /* 2946 * Lock down destination page. 2947 */ 2948 if (as_pagelock(as, &pplist, rdest, PAGESIZE, S_WRITE)) 2949 return (E2BIG); 2950 /* 2951 * Check if we have a shadow page list from as_pagelock. If not, 2952 * we took the slow path and have to find our page struct the hard 2953 * way. 2954 */ 2955 if (pplist == NULL) { 2956 pfn_t pfnum; 2957 2958 /* MMU mapping is already locked down */ 2959 AS_LOCK_ENTER(as, &as->a_lock, RW_READER); 2960 pfnum = hat_getpfnum(as->a_hat, rdest); 2961 AS_LOCK_EXIT(as, &as->a_lock); 2962 2963 /* 2964 * TODO: The pfn step should not be necessary - need 2965 * a hat_getpp() function. 2966 */ 2967 if (pf_is_memory(pfnum)) { 2968 pp = page_numtopp_nolock(pfnum); 2969 ASSERT(pp == NULL || PAGE_LOCKED(pp)); 2970 } else 2971 pp = NULL; 2972 if (pp == NULL) { 2973 as_pageunlock(as, pplist, rdest, PAGESIZE, S_WRITE); 2974 return (E2BIG); 2975 } 2976 } else { 2977 pp = *pplist; 2978 } 2979 /* 2980 * Map destination page into kernel address 2981 */ 2982 kaddr = (caddr_t)ppmapin(pp, PROT_READ | PROT_WRITE, (caddr_t)-1); 2983 2984 /* 2985 * Copy from src to dest 2986 */ 2987 if (copyin(src, kaddr + off, len) != 0) 2988 error = EFAULT; 2989 /* 2990 * Unmap destination page from kernel 2991 */ 2992 ppmapout(kaddr); 2993 /* 2994 * Unlock destination page 2995 */ 2996 as_pageunlock(as, pplist, rdest, PAGESIZE, S_WRITE); 2997 return (error); 2998 } 2999 3000 /* 3001 * General kernel upcall using doors 3002 * Returns 0 on success, errno for failures. 3003 * Caller must have a hold on the door based vnode, and on any 3004 * references passed in desc_ptr. The references are released 3005 * in the event of an error, and passed without duplication 3006 * otherwise. Note that param->rbuf must be 64-bit aligned in 3007 * a 64-bit kernel, since it may be used to store door descriptors 3008 * if they are returned by the server. 3009 */ 3010 int 3011 door_upcall(vnode_t *vp, door_arg_t *param) 3012 { 3013 /* Locals */ 3014 door_node_t *dp; 3015 kthread_t *server_thread; 3016 int error = 0; 3017 klwp_t *lwp; 3018 door_client_t *ct; /* curthread door_data */ 3019 door_server_t *st; /* server thread door_data */ 3020 int gotresults = 0; 3021 int cancel_pending; 3022 3023 if (vp->v_type != VDOOR) { 3024 if (param->desc_num) 3025 door_fd_rele(param->desc_ptr, param->desc_num, 1); 3026 return (EINVAL); 3027 } 3028 3029 lwp = ttolwp(curthread); 3030 ct = door_my_client(1); 3031 dp = VTOD(vp); /* Convert to a door_node_t */ 3032 3033 mutex_enter(&door_knob); 3034 if (DOOR_INVALID(dp)) { 3035 mutex_exit(&door_knob); 3036 if (param->desc_num) 3037 door_fd_rele(param->desc_ptr, param->desc_num, 1); 3038 error = EBADF; 3039 goto out; 3040 } 3041 3042 if (dp->door_target == &p0) { 3043 /* Can't do an upcall to a kernel server */ 3044 mutex_exit(&door_knob); 3045 if (param->desc_num) 3046 door_fd_rele(param->desc_ptr, param->desc_num, 1); 3047 error = EINVAL; 3048 goto out; 3049 } 3050 3051 error = door_check_limits(dp, param, 1); 3052 if (error != 0) { 3053 mutex_exit(&door_knob); 3054 if (param->desc_num) 3055 door_fd_rele(param->desc_ptr, param->desc_num, 1); 3056 goto out; 3057 } 3058 3059 /* 3060 * Get a server thread from the target domain 3061 */ 3062 if ((server_thread = door_get_server(dp)) == NULL) { 3063 if (DOOR_INVALID(dp)) 3064 error = EBADF; 3065 else 3066 error = EAGAIN; 3067 mutex_exit(&door_knob); 3068 if (param->desc_num) 3069 door_fd_rele(param->desc_ptr, param->desc_num, 1); 3070 goto out; 3071 } 3072 3073 st = DOOR_SERVER(server_thread->t_door); 3074 ct->d_buf = param->data_ptr; 3075 ct->d_bufsize = param->data_size; 3076 ct->d_args = *param; /* structure assignment */ 3077 3078 if (ct->d_args.desc_num) { 3079 /* 3080 * Move data from client to server 3081 */ 3082 DOOR_T_HOLD(st); 3083 mutex_exit(&door_knob); 3084 error = door_translate_out(); 3085 mutex_enter(&door_knob); 3086 DOOR_T_RELEASE(st); 3087 if (error) { 3088 /* 3089 * We're not going to resume this thread after all 3090 */ 3091 door_release_server(dp, server_thread); 3092 shuttle_sleep(server_thread); 3093 mutex_exit(&door_knob); 3094 goto out; 3095 } 3096 } 3097 3098 ct->d_upcall = 1; 3099 if (param->rsize == 0) 3100 ct->d_noresults = 1; 3101 else 3102 ct->d_noresults = 0; 3103 3104 dp->door_active++; 3105 3106 ct->d_error = DOOR_WAIT; 3107 st->d_caller = curthread; 3108 st->d_active = dp; 3109 3110 shuttle_resume(server_thread, &door_knob); 3111 3112 mutex_enter(&door_knob); 3113 shuttle_return: 3114 if ((error = ct->d_error) < 0) { /* DOOR_WAIT or DOOR_EXIT */ 3115 /* 3116 * Premature wakeup. Find out why (stop, forkall, sig, exit ...) 3117 */ 3118 mutex_exit(&door_knob); /* May block in ISSIG */ 3119 cancel_pending = 0; 3120 if (lwp && (ISSIG(curthread, FORREAL) || lwp->lwp_sysabort || 3121 MUSTRETURN(curproc, curthread) || 3122 (cancel_pending = schedctl_cancel_pending()) != 0)) { 3123 /* Signal, forkall, ... */ 3124 if (cancel_pending) 3125 schedctl_cancel_eintr(); 3126 lwp->lwp_sysabort = 0; 3127 mutex_enter(&door_knob); 3128 error = EINTR; 3129 /* 3130 * If the server has finished processing our call, 3131 * or exited (calling door_slam()), then d_error 3132 * will have changed. If the server hasn't finished 3133 * yet, d_error will still be DOOR_WAIT, and we 3134 * let it know we are not interested in any 3135 * results by sending a SIGCANCEL, unless the door 3136 * is marked with DOOR_NO_CANCEL. 3137 */ 3138 if (ct->d_error == DOOR_WAIT && 3139 st->d_caller == curthread) { 3140 proc_t *p = ttoproc(server_thread); 3141 3142 st->d_active = NULL; 3143 st->d_caller = NULL; 3144 if (!(dp->door_flags & DOOR_NO_CANCEL)) { 3145 DOOR_T_HOLD(st); 3146 mutex_exit(&door_knob); 3147 3148 mutex_enter(&p->p_lock); 3149 sigtoproc(p, server_thread, SIGCANCEL); 3150 mutex_exit(&p->p_lock); 3151 3152 mutex_enter(&door_knob); 3153 DOOR_T_RELEASE(st); 3154 } 3155 } 3156 } else { 3157 /* 3158 * Return from stop(), server exit... 3159 * 3160 * Note that the server could have done a 3161 * door_return while the client was in stop state 3162 * (ISSIG), in which case the error condition 3163 * is updated by the server. 3164 */ 3165 mutex_enter(&door_knob); 3166 if (ct->d_error == DOOR_WAIT) { 3167 /* Still waiting for a reply */ 3168 shuttle_swtch(&door_knob); 3169 mutex_enter(&door_knob); 3170 if (lwp) 3171 lwp->lwp_asleep = 0; 3172 goto shuttle_return; 3173 } else if (ct->d_error == DOOR_EXIT) { 3174 /* Server exit */ 3175 error = EINTR; 3176 } else { 3177 /* Server did a door_return during ISSIG */ 3178 error = ct->d_error; 3179 } 3180 } 3181 /* 3182 * Can't exit if the server is currently copying 3183 * results for me 3184 */ 3185 while (DOOR_T_HELD(ct)) 3186 cv_wait(&ct->d_cv, &door_knob); 3187 3188 /* 3189 * Find out if results were successfully copied. 3190 */ 3191 if (ct->d_error == 0) 3192 gotresults = 1; 3193 } 3194 if (lwp) { 3195 lwp->lwp_asleep = 0; /* /proc */ 3196 lwp->lwp_sysabort = 0; /* /proc */ 3197 } 3198 if (--dp->door_active == 0 && (dp->door_flags & DOOR_DELAY)) 3199 door_deliver_unref(dp); 3200 mutex_exit(&door_knob); 3201 3202 /* 3203 * Translate returned doors (if any) 3204 */ 3205 3206 if (ct->d_noresults) 3207 goto out; 3208 3209 if (error) { 3210 /* 3211 * If server returned results successfully, then we've 3212 * been interrupted and may need to clean up. 3213 */ 3214 if (gotresults) { 3215 ASSERT(error == EINTR); 3216 door_fp_close(ct->d_fpp, ct->d_args.desc_num); 3217 } 3218 goto out; 3219 } 3220 3221 if (ct->d_args.desc_num) { 3222 struct file **fpp; 3223 door_desc_t *didpp; 3224 vnode_t *vp; 3225 uint_t n = ct->d_args.desc_num; 3226 3227 didpp = ct->d_args.desc_ptr = (door_desc_t *)(ct->d_args.rbuf + 3228 roundup(ct->d_args.data_size, sizeof (door_desc_t))); 3229 fpp = ct->d_fpp; 3230 3231 while (n--) { 3232 struct file *fp; 3233 3234 fp = *fpp; 3235 if (VOP_REALVP(fp->f_vnode, &vp, NULL)) 3236 vp = fp->f_vnode; 3237 3238 didpp->d_attributes = DOOR_HANDLE | 3239 (VTOD(vp)->door_flags & DOOR_ATTR_MASK); 3240 didpp->d_data.d_handle = FTODH(fp); 3241 3242 fpp++; didpp++; 3243 } 3244 } 3245 3246 /* on return data is in rbuf */ 3247 *param = ct->d_args; /* structure assignment */ 3248 3249 out: 3250 if (ct->d_fpp) { 3251 kmem_free(ct->d_fpp, ct->d_fpp_size); 3252 ct->d_fpp = NULL; 3253 ct->d_fpp_size = 0; 3254 } 3255 3256 ct->d_upcall = 0; 3257 ct->d_noresults = 0; 3258 ct->d_buf = NULL; 3259 ct->d_bufsize = 0; 3260 return (error); 3261 } 3262 3263 /* 3264 * Add a door to the per-process list of active doors for which the 3265 * process is a server. 3266 */ 3267 static void 3268 door_list_insert(door_node_t *dp) 3269 { 3270 proc_t *p = dp->door_target; 3271 3272 ASSERT(MUTEX_HELD(&door_knob)); 3273 dp->door_list = p->p_door_list; 3274 p->p_door_list = dp; 3275 } 3276 3277 /* 3278 * Remove a door from the per-process list of active doors. 3279 */ 3280 void 3281 door_list_delete(door_node_t *dp) 3282 { 3283 door_node_t **pp; 3284 3285 ASSERT(MUTEX_HELD(&door_knob)); 3286 /* 3287 * Find the door in the list. If the door belongs to another process, 3288 * it's OK to use p_door_list since that process can't exit until all 3289 * doors have been taken off the list (see door_exit). 3290 */ 3291 pp = &(dp->door_target->p_door_list); 3292 while (*pp != dp) 3293 pp = &((*pp)->door_list); 3294 3295 /* found it, take it off the list */ 3296 *pp = dp->door_list; 3297 } 3298 3299 3300 /* 3301 * External kernel interfaces for doors. These functions are available 3302 * outside the doorfs module for use in creating and using doors from 3303 * within the kernel. 3304 */ 3305 3306 /* 3307 * door_ki_upcall invokes a user-level door server from the kernel. 3308 */ 3309 int 3310 door_ki_upcall(door_handle_t dh, door_arg_t *param) 3311 { 3312 file_t *fp = DHTOF(dh); 3313 vnode_t *realvp; 3314 3315 if (VOP_REALVP(fp->f_vnode, &realvp, NULL)) 3316 realvp = fp->f_vnode; 3317 return (door_upcall(realvp, param)); 3318 } 3319 3320 /* 3321 * Function call to create a "kernel" door server. A kernel door 3322 * server provides a way for a user-level process to invoke a function 3323 * in the kernel through a door_call. From the caller's point of 3324 * view, a kernel door server looks the same as a user-level one 3325 * (except the server pid is 0). Unlike normal door calls, the 3326 * kernel door function is invoked via a normal function call in the 3327 * same thread and context as the caller. 3328 */ 3329 int 3330 door_ki_create(void (*pc_cookie)(), void *data_cookie, uint_t attributes, 3331 door_handle_t *dhp) 3332 { 3333 int err; 3334 file_t *fp; 3335 3336 /* no DOOR_PRIVATE */ 3337 if ((attributes & ~DOOR_KI_CREATE_MASK) || 3338 (attributes & (DOOR_UNREF | DOOR_UNREF_MULTI)) == 3339 (DOOR_UNREF | DOOR_UNREF_MULTI)) 3340 return (EINVAL); 3341 3342 err = door_create_common(pc_cookie, data_cookie, attributes, 3343 1, NULL, &fp); 3344 if (err == 0 && (attributes & (DOOR_UNREF | DOOR_UNREF_MULTI)) && 3345 p0.p_unref_thread == 0) { 3346 /* need to create unref thread for process 0 */ 3347 (void) thread_create(NULL, 0, door_unref_kernel, NULL, 0, &p0, 3348 TS_RUN, minclsyspri); 3349 } 3350 if (err == 0) { 3351 *dhp = FTODH(fp); 3352 } 3353 return (err); 3354 } 3355 3356 void 3357 door_ki_hold(door_handle_t dh) 3358 { 3359 file_t *fp = DHTOF(dh); 3360 3361 mutex_enter(&fp->f_tlock); 3362 fp->f_count++; 3363 mutex_exit(&fp->f_tlock); 3364 } 3365 3366 void 3367 door_ki_rele(door_handle_t dh) 3368 { 3369 file_t *fp = DHTOF(dh); 3370 3371 (void) closef(fp); 3372 } 3373 3374 int 3375 door_ki_open(char *pathname, door_handle_t *dhp) 3376 { 3377 file_t *fp; 3378 vnode_t *vp; 3379 int err; 3380 3381 if ((err = lookupname(pathname, UIO_SYSSPACE, FOLLOW, NULL, &vp)) != 0) 3382 return (err); 3383 if (err = VOP_OPEN(&vp, FREAD, kcred, NULL)) { 3384 VN_RELE(vp); 3385 return (err); 3386 } 3387 if (vp->v_type != VDOOR) { 3388 VN_RELE(vp); 3389 return (EINVAL); 3390 } 3391 if ((err = falloc(vp, FREAD | FWRITE, &fp, NULL)) != 0) { 3392 VN_RELE(vp); 3393 return (err); 3394 } 3395 /* falloc returns with f_tlock held on success */ 3396 mutex_exit(&fp->f_tlock); 3397 *dhp = FTODH(fp); 3398 return (0); 3399 } 3400 3401 int 3402 door_ki_info(door_handle_t dh, struct door_info *dip) 3403 { 3404 file_t *fp = DHTOF(dh); 3405 vnode_t *vp; 3406 3407 if (VOP_REALVP(fp->f_vnode, &vp, NULL)) 3408 vp = fp->f_vnode; 3409 if (vp->v_type != VDOOR) 3410 return (EINVAL); 3411 door_info_common(VTOD(vp), dip, fp); 3412 return (0); 3413 } 3414 3415 door_handle_t 3416 door_ki_lookup(int did) 3417 { 3418 file_t *fp; 3419 door_handle_t dh; 3420 3421 /* is the descriptor really a door? */ 3422 if (door_lookup(did, &fp) == NULL) 3423 return (NULL); 3424 /* got the door, put a hold on it and release the fd */ 3425 dh = FTODH(fp); 3426 door_ki_hold(dh); 3427 releasef(did); 3428 return (dh); 3429 } 3430 3431 int 3432 door_ki_setparam(door_handle_t dh, int type, size_t val) 3433 { 3434 file_t *fp = DHTOF(dh); 3435 vnode_t *vp; 3436 3437 if (VOP_REALVP(fp->f_vnode, &vp, NULL)) 3438 vp = fp->f_vnode; 3439 if (vp->v_type != VDOOR) 3440 return (EINVAL); 3441 return (door_setparam_common(VTOD(vp), 1, type, val)); 3442 } 3443 3444 int 3445 door_ki_getparam(door_handle_t dh, int type, size_t *out) 3446 { 3447 file_t *fp = DHTOF(dh); 3448 vnode_t *vp; 3449 3450 if (VOP_REALVP(fp->f_vnode, &vp, NULL)) 3451 vp = fp->f_vnode; 3452 if (vp->v_type != VDOOR) 3453 return (EINVAL); 3454 return (door_getparam_common(VTOD(vp), type, out)); 3455 } 3456