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 (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26 /*
27 * System call I/F to doors (outside of vnodes I/F) and misc support
28 * routines
29 */
30 #include <sys/types.h>
31 #include <sys/systm.h>
32 #include <sys/door.h>
33 #include <sys/door_data.h>
34 #include <sys/proc.h>
35 #include <sys/thread.h>
36 #include <sys/prsystm.h>
37 #include <sys/procfs.h>
38 #include <sys/class.h>
39 #include <sys/cred.h>
40 #include <sys/kmem.h>
41 #include <sys/cmn_err.h>
42 #include <sys/stack.h>
43 #include <sys/debug.h>
44 #include <sys/cpuvar.h>
45 #include <sys/file.h>
46 #include <sys/fcntl.h>
47 #include <sys/vnode.h>
48 #include <sys/vfs.h>
49 #include <sys/vfs_opreg.h>
50 #include <sys/sobject.h>
51 #include <sys/schedctl.h>
52 #include <sys/callb.h>
53 #include <sys/ucred.h>
54
55 #include <sys/mman.h>
56 #include <sys/sysmacros.h>
57 #include <sys/vmsystm.h>
58 #include <vm/as.h>
59 #include <vm/hat.h>
60 #include <vm/page.h>
61 #include <vm/seg.h>
62 #include <vm/seg_vn.h>
63 #include <vm/seg_vn.h>
64 #include <vm/seg_kpm.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 needcleanup = 0;
518 int cancel_pending;
519
520 lwp = ttolwp(curthread);
521 datamodel = lwp_getdatamodel(lwp);
522
523 ct = door_my_client(1);
524
525 /*
526 * Get the arguments
527 */
528 if (args) {
529 if (datamodel == DATAMODEL_NATIVE) {
530 if (copyin(args, &ct->d_args, sizeof (door_arg_t)) != 0)
531 return (set_errno(EFAULT));
532 } else {
533 door_arg32_t da32;
534
535 if (copyin(args, &da32, sizeof (door_arg32_t)) != 0)
536 return (set_errno(EFAULT));
537 ct->d_args.data_ptr =
538 (char *)(uintptr_t)da32.data_ptr;
539 ct->d_args.data_size = da32.data_size;
540 ct->d_args.desc_ptr =
541 (door_desc_t *)(uintptr_t)da32.desc_ptr;
542 ct->d_args.desc_num = da32.desc_num;
543 ct->d_args.rbuf =
544 (char *)(uintptr_t)da32.rbuf;
545 ct->d_args.rsize = da32.rsize;
546 }
547 } else {
548 /* No arguments, and no results allowed */
549 ct->d_noresults = 1;
550 ct->d_args.data_size = 0;
551 ct->d_args.desc_num = 0;
552 ct->d_args.rsize = 0;
553 }
554
555 if ((dp = door_lookup(did, NULL)) == NULL)
556 return (set_errno(EBADF));
557
558 /*
559 * We don't want to hold the door FD over the entire operation;
560 * instead, we put a hold on the door vnode and release the FD
561 * immediately
562 */
563 VN_HOLD(DTOV(dp));
564 releasef(did);
565
566 /*
567 * This should be done in shuttle_resume(), just before going to
568 * sleep, but we want to avoid overhead while holding door_knob.
569 * prstop() is just a no-op if we don't really go to sleep.
570 * We test not-kernel-address-space for the sake of clustering code.
571 */
572 if (lwp && lwp->lwp_nostop == 0 && curproc->p_as != &kas)
573 prstop(PR_REQUESTED, 0);
574
575 mutex_enter(&door_knob);
576 if (DOOR_INVALID(dp)) {
577 mutex_exit(&door_knob);
578 error = EBADF;
579 goto out;
580 }
581
582 /*
583 * before we do anything, check that we are not overflowing the
584 * required limits.
585 */
586 error = door_check_limits(dp, &ct->d_args, 0);
587 if (error != 0) {
588 mutex_exit(&door_knob);
589 goto out;
590 }
591
592 /*
593 * Check for in-kernel door server.
594 */
595 if (dp->door_target == &p0) {
596 caddr_t rbuf = ct->d_args.rbuf;
597 size_t rsize = ct->d_args.rsize;
598
599 dp->door_active++;
600 ct->d_kernel = 1;
601 ct->d_error = DOOR_WAIT;
602 mutex_exit(&door_knob);
603 /* translate file descriptors to vnodes */
604 if (ct->d_args.desc_num) {
605 error = door_translate_in();
606 if (error)
607 goto out;
608 }
609 /*
610 * Call kernel door server. Arguments are passed and
611 * returned as a door_arg pointer. When called, data_ptr
612 * points to user data and desc_ptr points to a kernel list
613 * of door descriptors that have been converted to file
614 * structure pointers. It's the server function's
615 * responsibility to copyin the data pointed to by data_ptr
616 * (this avoids extra copying in some cases). On return,
617 * data_ptr points to a user buffer of data, and desc_ptr
618 * points to a kernel list of door descriptors representing
619 * files. When a reference is passed to a kernel server,
620 * it is the server's responsibility to release the reference
621 * (by calling closef). When the server includes a
622 * reference in its reply, it is released as part of the
623 * the call (the server must duplicate the reference if
624 * it wants to retain a copy). The destfn, if set to
625 * non-NULL, is a destructor to be called when the returned
626 * kernel data (if any) is no longer needed (has all been
627 * translated and copied to user level).
628 */
629 (*(dp->door_pc))(dp->door_data, &ct->d_args,
630 &destfn, &destarg, &error);
631 mutex_enter(&door_knob);
632 /* not implemented yet */
633 if (--dp->door_active == 0 && (dp->door_flags & DOOR_DELAY))
634 door_deliver_unref(dp);
635 mutex_exit(&door_knob);
636 if (error)
637 goto out;
638
639 /* translate vnodes to files */
640 if (ct->d_args.desc_num) {
641 error = door_translate_out();
642 if (error)
643 goto out;
644 }
645 ct->d_buf = ct->d_args.rbuf;
646 ct->d_bufsize = ct->d_args.rsize;
647 if (rsize < (ct->d_args.data_size +
648 (ct->d_args.desc_num * sizeof (door_desc_t)))) {
649 /* handle overflow */
650 error = door_overflow(curthread, ct->d_args.data_ptr,
651 ct->d_args.data_size, ct->d_args.desc_ptr,
652 ct->d_args.desc_num);
653 if (error)
654 goto out;
655 /* door_overflow sets d_args rbuf and rsize */
656 } else {
657 ct->d_args.rbuf = rbuf;
658 ct->d_args.rsize = rsize;
659 }
660 goto results;
661 }
662
663 /*
664 * Get a server thread from the target domain
665 */
666 if ((server_thread = door_get_server(dp)) == NULL) {
667 if (DOOR_INVALID(dp))
668 error = EBADF;
669 else
670 error = EAGAIN;
671 mutex_exit(&door_knob);
672 goto out;
673 }
674
675 st = DOOR_SERVER(server_thread->t_door);
676 if (ct->d_args.desc_num || ct->d_args.data_size) {
677 int is_private = (dp->door_flags & DOOR_PRIVATE);
678 /*
679 * Move data from client to server
680 */
681 DOOR_T_HOLD(st);
682 mutex_exit(&door_knob);
683 error = door_args(server_thread, is_private);
684 mutex_enter(&door_knob);
685 DOOR_T_RELEASE(st);
686 if (error) {
687 /*
688 * We're not going to resume this thread after all
689 */
690 door_release_server(dp, server_thread);
691 shuttle_sleep(server_thread);
692 mutex_exit(&door_knob);
693 goto out;
694 }
695 }
696
697 dp->door_active++;
698 ct->d_error = DOOR_WAIT;
699 ct->d_args_done = 0;
700 st->d_caller = curthread;
701 st->d_active = dp;
702
703 shuttle_resume(server_thread, &door_knob);
704
705 mutex_enter(&door_knob);
706 shuttle_return:
707 if ((error = ct->d_error) < 0) { /* DOOR_WAIT or DOOR_EXIT */
708 /*
709 * Premature wakeup. Find out why (stop, forkall, sig, exit ...)
710 */
711 mutex_exit(&door_knob); /* May block in ISSIG */
712 cancel_pending = 0;
713 if (ISSIG(curthread, FORREAL) || lwp->lwp_sysabort ||
714 MUSTRETURN(curproc, curthread) ||
715 (cancel_pending = schedctl_cancel_pending()) != 0) {
716 /* Signal, forkall, ... */
717 lwp->lwp_sysabort = 0;
718 if (cancel_pending)
719 schedctl_cancel_eintr();
720 mutex_enter(&door_knob);
721 error = EINTR;
722 /*
723 * If the server has finished processing our call,
724 * or exited (calling door_slam()), then d_error
725 * will have changed. If the server hasn't finished
726 * yet, d_error will still be DOOR_WAIT, and we
727 * let it know we are not interested in any
728 * results by sending a SIGCANCEL, unless the door
729 * is marked with DOOR_NO_CANCEL.
730 */
731 if (ct->d_error == DOOR_WAIT &&
732 st->d_caller == curthread) {
733 proc_t *p = ttoproc(server_thread);
734
735 st->d_active = NULL;
736 st->d_caller = NULL;
737
738 if (!(dp->door_flags & DOOR_NO_CANCEL)) {
739 DOOR_T_HOLD(st);
740 mutex_exit(&door_knob);
741
742 mutex_enter(&p->p_lock);
743 sigtoproc(p, server_thread, SIGCANCEL);
744 mutex_exit(&p->p_lock);
745
746 mutex_enter(&door_knob);
747 DOOR_T_RELEASE(st);
748 }
749 }
750 } else {
751 /*
752 * Return from stop(), server exit...
753 *
754 * Note that the server could have done a
755 * door_return while the client was in stop state
756 * (ISSIG), in which case the error condition
757 * is updated by the server.
758 */
759 mutex_enter(&door_knob);
760 if (ct->d_error == DOOR_WAIT) {
761 /* Still waiting for a reply */
762 shuttle_swtch(&door_knob);
763 mutex_enter(&door_knob);
764 lwp->lwp_asleep = 0;
765 goto shuttle_return;
766 } else if (ct->d_error == DOOR_EXIT) {
767 /* Server exit */
768 error = EINTR;
769 } else {
770 /* Server did a door_return during ISSIG */
771 error = ct->d_error;
772 }
773 }
774 /*
775 * Can't exit if the server is currently copying
776 * results for me.
777 */
778 while (DOOR_T_HELD(ct))
779 cv_wait(&ct->d_cv, &door_knob);
780
781 /*
782 * If the server has not processed our message, free the
783 * descriptors.
784 */
785 if (!ct->d_args_done) {
786 needcleanup = 1;
787 ct->d_args_done = 1;
788 }
789
790 /*
791 * Find out if results were successfully copied.
792 */
793 if (ct->d_error == 0)
794 gotresults = 1;
795 }
796 ASSERT(ct->d_args_done);
797 lwp->lwp_asleep = 0; /* /proc */
798 lwp->lwp_sysabort = 0; /* /proc */
799 if (--dp->door_active == 0 && (dp->door_flags & DOOR_DELAY))
800 door_deliver_unref(dp);
801 mutex_exit(&door_knob);
802
803 if (needcleanup)
804 door_fp_close(ct->d_fpp, ct->d_args.desc_num);
805
806 results:
807 /*
808 * Move the results to userland (if any)
809 */
810
811 if (ct->d_noresults)
812 goto out;
813
814 if (error) {
815 /*
816 * If server returned results successfully, then we've
817 * been interrupted and may need to clean up.
818 */
819 if (gotresults) {
820 ASSERT(error == EINTR);
821 door_fp_close(ct->d_fpp, ct->d_args.desc_num);
822 }
823 goto out;
824 }
825
826 /*
827 * Copy back data if we haven't caused an overflow (already
828 * handled) and we are using a 2 copy transfer, or we are
829 * returning data from a kernel server.
830 */
831 if (ct->d_args.data_size) {
832 ct->d_args.data_ptr = ct->d_args.rbuf;
833 if (ct->d_kernel || (!ct->d_overflow &&
834 ct->d_args.data_size <= door_max_arg)) {
835 if (copyout_nowatch(ct->d_buf, ct->d_args.rbuf,
836 ct->d_args.data_size)) {
837 door_fp_close(ct->d_fpp, ct->d_args.desc_num);
838 error = EFAULT;
839 goto out;
840 }
841 }
842 }
843
844 /*
845 * stuff returned doors into our proc, copyout the descriptors
846 */
847 if (ct->d_args.desc_num) {
848 struct file **fpp;
849 door_desc_t *didpp;
850 uint_t n = ct->d_args.desc_num;
851
852 dsize = n * sizeof (door_desc_t);
853 start = didpp = kmem_alloc(dsize, KM_SLEEP);
854 fpp = ct->d_fpp;
855
856 while (n--) {
857 if (door_insert(*fpp, didpp) == -1) {
858 /* Close remaining files */
859 door_fp_close(fpp, n + 1);
860 error = EMFILE;
861 goto out;
862 }
863 fpp++; didpp++; ncopied++;
864 }
865
866 ct->d_args.desc_ptr = (door_desc_t *)(ct->d_args.rbuf +
867 roundup(ct->d_args.data_size, sizeof (door_desc_t)));
868
869 if (copyout_nowatch(start, ct->d_args.desc_ptr, dsize)) {
870 error = EFAULT;
871 goto out;
872 }
873 }
874
875 /*
876 * Return the results
877 */
878 if (datamodel == DATAMODEL_NATIVE) {
879 if (copyout_nowatch(&ct->d_args, args,
880 sizeof (door_arg_t)) != 0)
881 error = EFAULT;
882 } else {
883 door_arg32_t da32;
884
885 da32.data_ptr = (caddr32_t)(uintptr_t)ct->d_args.data_ptr;
886 da32.data_size = ct->d_args.data_size;
887 da32.desc_ptr = (caddr32_t)(uintptr_t)ct->d_args.desc_ptr;
888 da32.desc_num = ct->d_args.desc_num;
889 da32.rbuf = (caddr32_t)(uintptr_t)ct->d_args.rbuf;
890 da32.rsize = ct->d_args.rsize;
891 if (copyout_nowatch(&da32, args, sizeof (door_arg32_t)) != 0) {
892 error = EFAULT;
893 }
894 }
895
896 out:
897 ct->d_noresults = 0;
898
899 /* clean up the overflow buffer if an error occurred */
900 if (error != 0 && ct->d_overflow) {
901 (void) as_unmap(curproc->p_as, ct->d_args.rbuf,
902 ct->d_args.rsize);
903 }
904 ct->d_overflow = 0;
905
906 /* call destructor */
907 if (destfn) {
908 ASSERT(ct->d_kernel);
909 (*destfn)(dp->door_data, destarg);
910 ct->d_buf = NULL;
911 ct->d_bufsize = 0;
912 }
913
914 if (dp)
915 VN_RELE(DTOV(dp));
916
917 if (ct->d_buf) {
918 ASSERT(!ct->d_kernel);
919 kmem_free(ct->d_buf, ct->d_bufsize);
920 ct->d_buf = NULL;
921 ct->d_bufsize = 0;
922 }
923 ct->d_kernel = 0;
924
925 /* clean up the descriptor copyout buffer */
926 if (start != NULL) {
927 if (error != 0)
928 door_fd_close(start, ncopied);
929 kmem_free(start, dsize);
930 }
931
932 if (ct->d_fpp) {
933 kmem_free(ct->d_fpp, ct->d_fpp_size);
934 ct->d_fpp = NULL;
935 ct->d_fpp_size = 0;
936 }
937
938 if (error)
939 return (set_errno(error));
940
941 return (0);
942 }
943
944 static int
945 door_setparam_common(door_node_t *dp, int from_kernel, int type, size_t val)
946 {
947 int error = 0;
948
949 mutex_enter(&door_knob);
950
951 if (DOOR_INVALID(dp)) {
952 mutex_exit(&door_knob);
953 return (EBADF);
954 }
955
956 /*
957 * door_ki_setparam() can only affect kernel doors.
958 * door_setparam() can only affect doors attached to the current
959 * process.
960 */
961 if ((from_kernel && dp->door_target != &p0) ||
962 (!from_kernel && dp->door_target != curproc)) {
963 mutex_exit(&door_knob);
964 return (EPERM);
965 }
966
967 switch (type) {
968 case DOOR_PARAM_DESC_MAX:
969 if (val > INT_MAX)
970 error = ERANGE;
971 else if ((dp->door_flags & DOOR_REFUSE_DESC) && val != 0)
972 error = ENOTSUP;
973 else
974 dp->door_desc_max = (uint_t)val;
975 break;
976
977 case DOOR_PARAM_DATA_MIN:
978 if (val > dp->door_data_max)
979 error = EINVAL;
980 else
981 dp->door_data_min = val;
982 break;
983
984 case DOOR_PARAM_DATA_MAX:
985 if (val < dp->door_data_min)
986 error = EINVAL;
987 else
988 dp->door_data_max = val;
989 break;
990
991 default:
992 error = EINVAL;
993 break;
994 }
995
996 mutex_exit(&door_knob);
997 return (error);
998 }
999
1000 static int
1001 door_getparam_common(door_node_t *dp, int type, size_t *out)
1002 {
1003 int error = 0;
1004
1005 mutex_enter(&door_knob);
1006 switch (type) {
1007 case DOOR_PARAM_DESC_MAX:
1008 *out = (size_t)dp->door_desc_max;
1009 break;
1010 case DOOR_PARAM_DATA_MIN:
1011 *out = dp->door_data_min;
1012 break;
1013 case DOOR_PARAM_DATA_MAX:
1014 *out = dp->door_data_max;
1015 break;
1016 default:
1017 error = EINVAL;
1018 break;
1019 }
1020 mutex_exit(&door_knob);
1021 return (error);
1022 }
1023
1024 int
1025 door_setparam(int did, int type, size_t val)
1026 {
1027 door_node_t *dp;
1028 int error = 0;
1029
1030 if ((dp = door_lookup(did, NULL)) == NULL)
1031 return (set_errno(EBADF));
1032
1033 error = door_setparam_common(dp, 0, type, val);
1034
1035 releasef(did);
1036
1037 if (error)
1038 return (set_errno(error));
1039
1040 return (0);
1041 }
1042
1043 int
1044 door_getparam(int did, int type, size_t *out)
1045 {
1046 door_node_t *dp;
1047 size_t val = 0;
1048 int error = 0;
1049
1050 if ((dp = door_lookup(did, NULL)) == NULL)
1051 return (set_errno(EBADF));
1052
1053 error = door_getparam_common(dp, type, &val);
1054
1055 releasef(did);
1056
1057 if (error)
1058 return (set_errno(error));
1059
1060 if (get_udatamodel() == DATAMODEL_NATIVE) {
1061 if (copyout(&val, out, sizeof (val)))
1062 return (set_errno(EFAULT));
1063 #ifdef _SYSCALL32_IMPL
1064 } else {
1065 size32_t val32 = (size32_t)val;
1066
1067 if (val != val32)
1068 return (set_errno(EOVERFLOW));
1069
1070 if (copyout(&val32, out, sizeof (val32)))
1071 return (set_errno(EFAULT));
1072 #endif /* _SYSCALL32_IMPL */
1073 }
1074
1075 return (0);
1076 }
1077
1078 /*
1079 * A copyout() which proceeds from high addresses to low addresses. This way,
1080 * stack guard pages are effective.
1081 *
1082 * Note that we use copyout_nowatch(); this is called while the client is
1083 * held.
1084 */
1085 static int
1086 door_stack_copyout(const void *kaddr, void *uaddr, size_t count)
1087 {
1088 const char *kbase = (const char *)kaddr;
1089 uintptr_t ubase = (uintptr_t)uaddr;
1090 size_t pgsize = PAGESIZE;
1091
1092 if (count <= pgsize)
1093 return (copyout_nowatch(kaddr, uaddr, count));
1094
1095 while (count > 0) {
1096 uintptr_t start, end, offset, amount;
1097
1098 end = ubase + count;
1099 start = P2ALIGN(end - 1, pgsize);
1100 if (P2ALIGN(ubase, pgsize) == start)
1101 start = ubase;
1102
1103 offset = start - ubase;
1104 amount = end - start;
1105
1106 ASSERT(amount > 0 && amount <= count && amount <= pgsize);
1107
1108 if (copyout_nowatch(kbase + offset, (void *)start, amount))
1109 return (1);
1110 count -= amount;
1111 }
1112 return (0);
1113 }
1114
1115 /*
1116 * Writes the stack layout for door_return() into the door_server_t of the
1117 * server thread.
1118 */
1119 static int
1120 door_layout(kthread_t *tp, size_t data_size, uint_t ndesc, int info_needed)
1121 {
1122 door_server_t *st = DOOR_SERVER(tp->t_door);
1123 door_layout_t *out = &st->d_layout;
1124 uintptr_t base_sp = (uintptr_t)st->d_sp;
1125 size_t ssize = st->d_ssize;
1126 size_t descsz;
1127 uintptr_t descp, datap, infop, resultsp, finalsp;
1128 size_t align = STACK_ALIGN;
1129 size_t results_sz = sizeof (struct door_results);
1130 model_t datamodel = lwp_getdatamodel(ttolwp(tp));
1131
1132 ASSERT(!st->d_layout_done);
1133
1134 #ifndef _STACK_GROWS_DOWNWARD
1135 #error stack does not grow downward, door_layout() must change
1136 #endif
1137
1138 #ifdef _SYSCALL32_IMPL
1139 if (datamodel != DATAMODEL_NATIVE) {
1140 align = STACK_ALIGN32;
1141 results_sz = sizeof (struct door_results32);
1142 }
1143 #endif
1144
1145 descsz = ndesc * sizeof (door_desc_t);
1146
1147 /*
1148 * To speed up the overflow checking, we do an initial check
1149 * that the passed in data size won't cause us to wrap past
1150 * base_sp. Since door_max_desc limits descsz, we can
1151 * safely use it here. 65535 is an arbitrary 'bigger than
1152 * we need, small enough to not cause trouble' constant;
1153 * the only constraint is that it must be > than:
1154 *
1155 * 5 * STACK_ALIGN +
1156 * sizeof (door_info_t) +
1157 * sizeof (door_results_t) +
1158 * (max adjustment from door_final_sp())
1159 *
1160 * After we compute the layout, we can safely do a "did we wrap
1161 * around" check, followed by a check against the recorded
1162 * stack size.
1163 */
1164 if (data_size >= SIZE_MAX - (size_t)65535UL - descsz)
1165 return (E2BIG); /* overflow */
1166
1167 descp = P2ALIGN(base_sp - descsz, align);
1168 datap = P2ALIGN(descp - data_size, align);
1169
1170 if (info_needed)
1171 infop = P2ALIGN(datap - sizeof (door_info_t), align);
1172 else
1173 infop = datap;
1174
1175 resultsp = P2ALIGN(infop - results_sz, align);
1176 finalsp = door_final_sp(resultsp, align, datamodel);
1177
1178 if (finalsp > base_sp)
1179 return (E2BIG); /* overflow */
1180
1181 if (ssize != 0 && (base_sp - finalsp) > ssize)
1182 return (E2BIG); /* doesn't fit in stack */
1183
1184 out->dl_descp = (ndesc != 0)? (caddr_t)descp : 0;
1185 out->dl_datap = (data_size != 0)? (caddr_t)datap : 0;
1186 out->dl_infop = info_needed? (caddr_t)infop : 0;
1187 out->dl_resultsp = (caddr_t)resultsp;
1188 out->dl_sp = (caddr_t)finalsp;
1189
1190 st->d_layout_done = 1;
1191 return (0);
1192 }
1193
1194 static int
1195 door_server_dispatch(door_client_t *ct, door_node_t *dp)
1196 {
1197 door_server_t *st = DOOR_SERVER(curthread->t_door);
1198 door_layout_t *layout = &st->d_layout;
1199 int error = 0;
1200
1201 int is_private = (dp->door_flags & DOOR_PRIVATE);
1202
1203 door_pool_t *pool = (is_private)? &dp->door_servers :
1204 &curproc->p_server_threads;
1205
1206 int empty_pool = (pool->dp_threads == NULL);
1207
1208 caddr_t infop = NULL;
1209 char *datap = NULL;
1210 size_t datasize = 0;
1211 size_t descsize;
1212
1213 file_t **fpp = ct->d_fpp;
1214 door_desc_t *start = NULL;
1215 uint_t ndesc = 0;
1216 uint_t ncopied = 0;
1217
1218 if (ct != NULL) {
1219 datap = ct->d_args.data_ptr;
1220 datasize = ct->d_args.data_size;
1221 ndesc = ct->d_args.desc_num;
1222 }
1223
1224 descsize = ndesc * sizeof (door_desc_t);
1225
1226 /*
1227 * Reset datap to NULL if we aren't passing any data. Be careful
1228 * to let unref notifications through, though.
1229 */
1230 if (datap == DOOR_UNREF_DATA) {
1231 if (ct->d_upcall != NULL)
1232 datasize = 0;
1233 else
1234 datap = NULL;
1235 } else if (datasize == 0) {
1236 datap = NULL;
1237 }
1238
1239 /*
1240 * Get the stack layout, if it hasn't already been done.
1241 */
1242 if (!st->d_layout_done) {
1243 error = door_layout(curthread, datasize, ndesc,
1244 (is_private && empty_pool));
1245 if (error != 0)
1246 goto fail;
1247 }
1248
1249 /*
1250 * fill out the stack, starting from the top. Layout was already
1251 * filled in by door_args() or door_translate_out().
1252 */
1253 if (layout->dl_descp != NULL) {
1254 ASSERT(ndesc != 0);
1255 start = kmem_alloc(descsize, KM_SLEEP);
1256
1257 while (ndesc > 0) {
1258 if (door_insert(*fpp, &start[ncopied]) == -1) {
1259 error = EMFILE;
1260 goto fail;
1261 }
1262 ndesc--;
1263 ncopied++;
1264 fpp++;
1265 }
1266 if (door_stack_copyout(start, layout->dl_descp, descsize)) {
1267 error = E2BIG;
1268 goto fail;
1269 }
1270 }
1271 fpp = NULL; /* finished processing */
1272
1273 if (layout->dl_datap != NULL) {
1274 ASSERT(datasize != 0);
1275 datap = layout->dl_datap;
1276 if (ct->d_upcall != NULL || datasize <= door_max_arg) {
1277 if (door_stack_copyout(ct->d_buf, datap, datasize)) {
1278 error = E2BIG;
1279 goto fail;
1280 }
1281 }
1282 }
1283
1284 if (is_private && empty_pool) {
1285 door_info_t di;
1286
1287 infop = layout->dl_infop;
1288 ASSERT(infop != NULL);
1289
1290 di.di_target = curproc->p_pid;
1291 di.di_proc = (door_ptr_t)(uintptr_t)dp->door_pc;
1292 di.di_data = (door_ptr_t)(uintptr_t)dp->door_data;
1293 di.di_uniquifier = dp->door_index;
1294 di.di_attributes = (dp->door_flags & DOOR_ATTR_MASK) |
1295 DOOR_LOCAL;
1296
1297 if (door_stack_copyout(&di, infop, sizeof (di))) {
1298 error = E2BIG;
1299 goto fail;
1300 }
1301 }
1302
1303 if (get_udatamodel() == DATAMODEL_NATIVE) {
1304 struct door_results dr;
1305
1306 dr.cookie = dp->door_data;
1307 dr.data_ptr = datap;
1308 dr.data_size = datasize;
1309 dr.desc_ptr = (door_desc_t *)layout->dl_descp;
1310 dr.desc_num = ncopied;
1311 dr.pc = dp->door_pc;
1312 dr.nservers = !empty_pool;
1313 dr.door_info = (door_info_t *)infop;
1314
1315 if (door_stack_copyout(&dr, layout->dl_resultsp, sizeof (dr))) {
1316 error = E2BIG;
1317 goto fail;
1318 }
1319 #ifdef _SYSCALL32_IMPL
1320 } else {
1321 struct door_results32 dr32;
1322
1323 dr32.cookie = (caddr32_t)(uintptr_t)dp->door_data;
1324 dr32.data_ptr = (caddr32_t)(uintptr_t)datap;
1325 dr32.data_size = (size32_t)datasize;
1326 dr32.desc_ptr = (caddr32_t)(uintptr_t)layout->dl_descp;
1327 dr32.desc_num = ncopied;
1328 dr32.pc = (caddr32_t)(uintptr_t)dp->door_pc;
1329 dr32.nservers = !empty_pool;
1330 dr32.door_info = (caddr32_t)(uintptr_t)infop;
1331
1332 if (door_stack_copyout(&dr32, layout->dl_resultsp,
1333 sizeof (dr32))) {
1334 error = E2BIG;
1335 goto fail;
1336 }
1337 #endif
1338 }
1339
1340 error = door_finish_dispatch(layout->dl_sp);
1341 fail:
1342 if (start != NULL) {
1343 if (error != 0)
1344 door_fd_close(start, ncopied);
1345 kmem_free(start, descsize);
1346 }
1347 if (fpp != NULL)
1348 door_fp_close(fpp, ndesc);
1349
1350 return (error);
1351 }
1352
1353 /*
1354 * Return the results (if any) to the caller (if any) and wait for the
1355 * next invocation on a door.
1356 */
1357 int
1358 door_return(caddr_t data_ptr, size_t data_size,
1359 door_desc_t *desc_ptr, uint_t desc_num, caddr_t sp, size_t ssize)
1360 {
1361 kthread_t *caller;
1362 klwp_t *lwp;
1363 int error = 0;
1364 door_node_t *dp;
1365 door_server_t *st; /* curthread door_data */
1366 door_client_t *ct; /* caller door_data */
1367 int cancel_pending;
1368
1369 st = door_my_server(1);
1370
1371 /*
1372 * If thread was bound to a door that no longer exists, return
1373 * an error. This can happen if a thread is bound to a door
1374 * before the process calls forkall(); in the child, the door
1375 * doesn't exist and door_fork() sets the d_invbound flag.
1376 */
1377 if (st->d_invbound)
1378 return (set_errno(EINVAL));
1379
1380 st->d_sp = sp; /* Save base of stack. */
1381 st->d_ssize = ssize; /* and its size */
1382
1383 /*
1384 * This should be done in shuttle_resume(), just before going to
1385 * sleep, but we want to avoid overhead while holding door_knob.
1386 * prstop() is just a no-op if we don't really go to sleep.
1387 * We test not-kernel-address-space for the sake of clustering code.
1388 */
1389 lwp = ttolwp(curthread);
1390 if (lwp && lwp->lwp_nostop == 0 && curproc->p_as != &kas)
1391 prstop(PR_REQUESTED, 0);
1392
1393 /* Make sure the caller hasn't gone away */
1394 mutex_enter(&door_knob);
1395 if ((caller = st->d_caller) == NULL || caller->t_door == NULL) {
1396 if (desc_num != 0) {
1397 /* close any DOOR_RELEASE descriptors */
1398 mutex_exit(&door_knob);
1399 error = door_release_fds(desc_ptr, desc_num);
1400 if (error)
1401 return (set_errno(error));
1402 mutex_enter(&door_knob);
1403 }
1404 goto out;
1405 }
1406 ct = DOOR_CLIENT(caller->t_door);
1407
1408 ct->d_args.data_size = data_size;
1409 ct->d_args.desc_num = desc_num;
1410 /*
1411 * Transfer results, if any, to the client
1412 */
1413 if (data_size != 0 || desc_num != 0) {
1414 /*
1415 * Prevent the client from exiting until we have finished
1416 * moving results.
1417 */
1418 DOOR_T_HOLD(ct);
1419 mutex_exit(&door_knob);
1420 error = door_results(caller, data_ptr, data_size,
1421 desc_ptr, desc_num);
1422 mutex_enter(&door_knob);
1423 DOOR_T_RELEASE(ct);
1424 /*
1425 * Pass EOVERFLOW errors back to the client
1426 */
1427 if (error && error != EOVERFLOW) {
1428 mutex_exit(&door_knob);
1429 return (set_errno(error));
1430 }
1431 }
1432 out:
1433 /* Put ourselves on the available server thread list */
1434 door_release_server(st->d_pool, curthread);
1435
1436 /*
1437 * Make sure the caller is still waiting to be resumed
1438 */
1439 if (caller) {
1440 disp_lock_t *tlp;
1441
1442 thread_lock(caller);
1443 ct->d_error = error; /* Return any errors */
1444 if (caller->t_state == TS_SLEEP &&
1445 SOBJ_TYPE(caller->t_sobj_ops) == SOBJ_SHUTTLE) {
1446 cpu_t *cp = CPU;
1447
1448 tlp = caller->t_lockp;
1449 /*
1450 * Setting t_disp_queue prevents erroneous preemptions
1451 * if this thread is still in execution on another
1452 * processor
1453 */
1454 caller->t_disp_queue = cp->cpu_disp;
1455 CL_ACTIVE(caller);
1456 /*
1457 * We are calling thread_onproc() instead of
1458 * THREAD_ONPROC() because compiler can reorder
1459 * the two stores of t_state and t_lockp in
1460 * THREAD_ONPROC().
1461 */
1462 thread_onproc(caller, cp);
1463 disp_lock_exit_high(tlp);
1464 shuttle_resume(caller, &door_knob);
1465 } else {
1466 /* May have been setrun or in stop state */
1467 thread_unlock(caller);
1468 shuttle_swtch(&door_knob);
1469 }
1470 } else {
1471 shuttle_swtch(&door_knob);
1472 }
1473
1474 /*
1475 * We've sprung to life. Determine if we are part of a door
1476 * invocation, or just interrupted
1477 */
1478 mutex_enter(&door_knob);
1479 if ((dp = st->d_active) != NULL) {
1480 /*
1481 * Normal door invocation. Return any error condition
1482 * encountered while trying to pass args to the server
1483 * thread.
1484 */
1485 lwp->lwp_asleep = 0;
1486 /*
1487 * Prevent the caller from leaving us while we
1488 * are copying out the arguments from it's buffer.
1489 */
1490 ASSERT(st->d_caller != NULL);
1491 ct = DOOR_CLIENT(st->d_caller->t_door);
1492
1493 DOOR_T_HOLD(ct);
1494 mutex_exit(&door_knob);
1495 error = door_server_dispatch(ct, dp);
1496 mutex_enter(&door_knob);
1497 DOOR_T_RELEASE(ct);
1498
1499 /* let the client know we have processed his message */
1500 ct->d_args_done = 1;
1501
1502 if (error) {
1503 caller = st->d_caller;
1504 if (caller)
1505 ct = DOOR_CLIENT(caller->t_door);
1506 else
1507 ct = NULL;
1508 goto out;
1509 }
1510 mutex_exit(&door_knob);
1511 return (0);
1512 } else {
1513 /*
1514 * We are not involved in a door_invocation.
1515 * Check for /proc related activity...
1516 */
1517 st->d_caller = NULL;
1518 door_server_exit(curproc, curthread);
1519 mutex_exit(&door_knob);
1520 cancel_pending = 0;
1521 if (ISSIG(curthread, FORREAL) || lwp->lwp_sysabort ||
1522 MUSTRETURN(curproc, curthread) ||
1523 (cancel_pending = schedctl_cancel_pending()) != 0) {
1524 if (cancel_pending)
1525 schedctl_cancel_eintr();
1526 lwp->lwp_asleep = 0;
1527 lwp->lwp_sysabort = 0;
1528 return (set_errno(EINTR));
1529 }
1530 /* Go back and wait for another request */
1531 lwp->lwp_asleep = 0;
1532 mutex_enter(&door_knob);
1533 caller = NULL;
1534 goto out;
1535 }
1536 }
1537
1538 /*
1539 * Revoke any future invocations on this door
1540 */
1541 int
1542 door_revoke(int did)
1543 {
1544 door_node_t *d;
1545 int error;
1546
1547 if ((d = door_lookup(did, NULL)) == NULL)
1548 return (set_errno(EBADF));
1549
1550 mutex_enter(&door_knob);
1551 if (d->door_target != curproc) {
1552 mutex_exit(&door_knob);
1553 releasef(did);
1554 return (set_errno(EPERM));
1555 }
1556 d->door_flags |= DOOR_REVOKED;
1557 if (d->door_flags & DOOR_PRIVATE)
1558 cv_broadcast(&d->door_servers.dp_cv);
1559 else
1560 cv_broadcast(&curproc->p_server_threads.dp_cv);
1561 mutex_exit(&door_knob);
1562 releasef(did);
1563 /* Invalidate the descriptor */
1564 if ((error = closeandsetf(did, NULL)) != 0)
1565 return (set_errno(error));
1566 return (0);
1567 }
1568
1569 int
1570 door_info(int did, struct door_info *d_info)
1571 {
1572 door_node_t *dp;
1573 door_info_t di;
1574 door_server_t *st;
1575 file_t *fp = NULL;
1576
1577 if (did == DOOR_QUERY) {
1578 /* Get information on door current thread is bound to */
1579 if ((st = door_my_server(0)) == NULL ||
1580 (dp = st->d_pool) == NULL)
1581 /* Thread isn't bound to a door */
1582 return (set_errno(EBADF));
1583 } else if ((dp = door_lookup(did, &fp)) == NULL) {
1584 /* Not a door */
1585 return (set_errno(EBADF));
1586 }
1587
1588 door_info_common(dp, &di, fp);
1589
1590 if (did != DOOR_QUERY)
1591 releasef(did);
1592
1593 if (copyout(&di, d_info, sizeof (struct door_info)))
1594 return (set_errno(EFAULT));
1595 return (0);
1596 }
1597
1598 /*
1599 * Common code for getting information about a door either via the
1600 * door_info system call or the door_ki_info kernel call.
1601 */
1602 void
1603 door_info_common(door_node_t *dp, struct door_info *dip, file_t *fp)
1604 {
1605 int unref_count;
1606
1607 bzero(dip, sizeof (door_info_t));
1608
1609 mutex_enter(&door_knob);
1610 if (dp->door_target == NULL)
1611 dip->di_target = -1;
1612 else
1613 dip->di_target = dp->door_target->p_pid;
1614
1615 dip->di_attributes = dp->door_flags & DOOR_ATTR_MASK;
1616 if (dp->door_target == curproc)
1617 dip->di_attributes |= DOOR_LOCAL;
1618 dip->di_proc = (door_ptr_t)(uintptr_t)dp->door_pc;
1619 dip->di_data = (door_ptr_t)(uintptr_t)dp->door_data;
1620 dip->di_uniquifier = dp->door_index;
1621 /*
1622 * If this door is in the middle of having an unreferenced
1623 * notification delivered, don't count the VN_HOLD by
1624 * door_deliver_unref in determining if it is unreferenced.
1625 * This handles the case where door_info is called from the
1626 * thread delivering the unref notification.
1627 */
1628 if (dp->door_flags & DOOR_UNREF_ACTIVE)
1629 unref_count = 2;
1630 else
1631 unref_count = 1;
1632 mutex_exit(&door_knob);
1633
1634 if (fp == NULL) {
1635 /*
1636 * If this thread is bound to the door, then we can just
1637 * check the vnode; a ref count of 1 (or 2 if this is
1638 * handling an unref notification) means that the hold
1639 * from the door_bind is the only reference to the door
1640 * (no file descriptor refers to it).
1641 */
1642 if (DTOV(dp)->v_count == unref_count)
1643 dip->di_attributes |= DOOR_IS_UNREF;
1644 } else {
1645 /*
1646 * If we're working from a file descriptor or door handle
1647 * we need to look at the file structure count. We don't
1648 * need to hold the vnode lock since this is just a snapshot.
1649 */
1650 mutex_enter(&fp->f_tlock);
1651 if (fp->f_count == 1 && DTOV(dp)->v_count == unref_count)
1652 dip->di_attributes |= DOOR_IS_UNREF;
1653 mutex_exit(&fp->f_tlock);
1654 }
1655 }
1656
1657 /*
1658 * Return credentials of the door caller (if any) for this invocation
1659 */
1660 int
1661 door_ucred(struct ucred_s *uch)
1662 {
1663 kthread_t *caller;
1664 door_server_t *st;
1665 door_client_t *ct;
1666 door_upcall_t *dup;
1667 struct proc *p;
1668 struct ucred_s *res;
1669 int err;
1670
1671 mutex_enter(&door_knob);
1672 if ((st = door_my_server(0)) == NULL ||
1673 (caller = st->d_caller) == NULL) {
1674 mutex_exit(&door_knob);
1675 return (set_errno(EINVAL));
1676 }
1677
1678 ASSERT(caller->t_door != NULL);
1679 ct = DOOR_CLIENT(caller->t_door);
1680
1681 /* Prevent caller from exiting while we examine the cred */
1682 DOOR_T_HOLD(ct);
1683 mutex_exit(&door_knob);
1684
1685 p = ttoproc(caller);
1686
1687 /*
1688 * If the credentials are not specified by the client, get the one
1689 * associated with the calling process.
1690 */
1691 if ((dup = ct->d_upcall) != NULL)
1692 res = cred2ucred(dup->du_cred, p0.p_pid, NULL, CRED());
1693 else
1694 res = cred2ucred(caller->t_cred, p->p_pid, NULL, CRED());
1695
1696 mutex_enter(&door_knob);
1697 DOOR_T_RELEASE(ct);
1698 mutex_exit(&door_knob);
1699
1700 err = copyout(res, uch, res->uc_size);
1701
1702 kmem_free(res, res->uc_size);
1703
1704 if (err != 0)
1705 return (set_errno(EFAULT));
1706
1707 return (0);
1708 }
1709
1710 /*
1711 * Bind the current lwp to the server thread pool associated with 'did'
1712 */
1713 int
1714 door_bind(int did)
1715 {
1716 door_node_t *dp;
1717 door_server_t *st;
1718
1719 if ((dp = door_lookup(did, NULL)) == NULL) {
1720 /* Not a door */
1721 return (set_errno(EBADF));
1722 }
1723
1724 /*
1725 * Can't bind to a non-private door, and can't bind to a door
1726 * served by another process.
1727 */
1728 if ((dp->door_flags & DOOR_PRIVATE) == 0 ||
1729 dp->door_target != curproc) {
1730 releasef(did);
1731 return (set_errno(EINVAL));
1732 }
1733
1734 st = door_my_server(1);
1735 if (st->d_pool)
1736 door_unbind_thread(st->d_pool);
1737 st->d_pool = dp;
1738 st->d_invbound = 0;
1739 door_bind_thread(dp);
1740 releasef(did);
1741
1742 return (0);
1743 }
1744
1745 /*
1746 * Unbind the current lwp from it's server thread pool
1747 */
1748 int
1749 door_unbind(void)
1750 {
1751 door_server_t *st;
1752
1753 if ((st = door_my_server(0)) == NULL)
1754 return (set_errno(EBADF));
1755
1756 if (st->d_invbound) {
1757 ASSERT(st->d_pool == NULL);
1758 st->d_invbound = 0;
1759 return (0);
1760 }
1761 if (st->d_pool == NULL)
1762 return (set_errno(EBADF));
1763 door_unbind_thread(st->d_pool);
1764 st->d_pool = NULL;
1765 return (0);
1766 }
1767
1768 /*
1769 * Create a descriptor for the associated file and fill in the
1770 * attributes associated with it.
1771 *
1772 * Return 0 for success, -1 otherwise;
1773 */
1774 int
1775 door_insert(struct file *fp, door_desc_t *dp)
1776 {
1777 struct vnode *vp;
1778 int fd;
1779 door_attr_t attributes = DOOR_DESCRIPTOR;
1780
1781 ASSERT(MUTEX_NOT_HELD(&door_knob));
1782 if ((fd = ufalloc(0)) == -1)
1783 return (-1);
1784 setf(fd, fp);
1785 dp->d_data.d_desc.d_descriptor = fd;
1786
1787 /* Fill in the attributes */
1788 if (VOP_REALVP(fp->f_vnode, &vp, NULL))
1789 vp = fp->f_vnode;
1790 if (vp && vp->v_type == VDOOR) {
1791 if (VTOD(vp)->door_target == curproc)
1792 attributes |= DOOR_LOCAL;
1793 attributes |= VTOD(vp)->door_flags & DOOR_ATTR_MASK;
1794 dp->d_data.d_desc.d_id = VTOD(vp)->door_index;
1795 }
1796 dp->d_attributes = attributes;
1797 return (0);
1798 }
1799
1800 /*
1801 * Return an available thread for this server. A NULL return value indicates
1802 * that either:
1803 * The door has been revoked, or
1804 * a signal was received.
1805 * The two conditions can be differentiated using DOOR_INVALID(dp).
1806 */
1807 static kthread_t *
1808 door_get_server(door_node_t *dp)
1809 {
1810 kthread_t **ktp;
1811 kthread_t *server_t;
1812 door_pool_t *pool;
1813 door_server_t *st;
1814 int signalled;
1815
1816 disp_lock_t *tlp;
1817 cpu_t *cp;
1818
1819 ASSERT(MUTEX_HELD(&door_knob));
1820
1821 if (dp->door_flags & DOOR_PRIVATE)
1822 pool = &dp->door_servers;
1823 else
1824 pool = &dp->door_target->p_server_threads;
1825
1826 for (;;) {
1827 /*
1828 * We search the thread pool, looking for a server thread
1829 * ready to take an invocation (i.e. one which is still
1830 * sleeping on a shuttle object). If none are available,
1831 * we sleep on the pool's CV, and will be signaled when a
1832 * thread is added to the pool.
1833 *
1834 * This relies on the fact that once a thread in the thread
1835 * pool wakes up, it *must* remove and add itself to the pool
1836 * before it can receive door calls.
1837 */
1838 if (DOOR_INVALID(dp))
1839 return (NULL); /* Target has become invalid */
1840
1841 for (ktp = &pool->dp_threads;
1842 (server_t = *ktp) != NULL;
1843 ktp = &st->d_servers) {
1844 st = DOOR_SERVER(server_t->t_door);
1845
1846 thread_lock(server_t);
1847 if (server_t->t_state == TS_SLEEP &&
1848 SOBJ_TYPE(server_t->t_sobj_ops) == SOBJ_SHUTTLE)
1849 break;
1850 thread_unlock(server_t);
1851 }
1852 if (server_t != NULL)
1853 break; /* we've got a live one! */
1854
1855 if (!cv_wait_sig_swap_core(&pool->dp_cv, &door_knob,
1856 &signalled)) {
1857 /*
1858 * If we were signaled and the door is still
1859 * valid, pass the signal on to another waiter.
1860 */
1861 if (signalled && !DOOR_INVALID(dp))
1862 cv_signal(&pool->dp_cv);
1863 return (NULL); /* Got a signal */
1864 }
1865 }
1866
1867 /*
1868 * We've got a thread_lock()ed thread which is still on the
1869 * shuttle. Take it off the list of available server threads
1870 * and mark it as ONPROC. We are committed to resuming this
1871 * thread now.
1872 */
1873 tlp = server_t->t_lockp;
1874 cp = CPU;
1875
1876 *ktp = st->d_servers;
1877 st->d_servers = NULL;
1878 /*
1879 * Setting t_disp_queue prevents erroneous preemptions
1880 * if this thread is still in execution on another processor
1881 */
1882 server_t->t_disp_queue = cp->cpu_disp;
1883 CL_ACTIVE(server_t);
1884 /*
1885 * We are calling thread_onproc() instead of
1886 * THREAD_ONPROC() because compiler can reorder
1887 * the two stores of t_state and t_lockp in
1888 * THREAD_ONPROC().
1889 */
1890 thread_onproc(server_t, cp);
1891 disp_lock_exit(tlp);
1892 return (server_t);
1893 }
1894
1895 /*
1896 * Put a server thread back in the pool.
1897 */
1898 static void
1899 door_release_server(door_node_t *dp, kthread_t *t)
1900 {
1901 door_server_t *st = DOOR_SERVER(t->t_door);
1902 door_pool_t *pool;
1903
1904 ASSERT(MUTEX_HELD(&door_knob));
1905 st->d_active = NULL;
1906 st->d_caller = NULL;
1907 st->d_layout_done = 0;
1908 if (dp && (dp->door_flags & DOOR_PRIVATE)) {
1909 ASSERT(dp->door_target == NULL ||
1910 dp->door_target == ttoproc(t));
1911 pool = &dp->door_servers;
1912 } else {
1913 pool = &ttoproc(t)->p_server_threads;
1914 }
1915
1916 st->d_servers = pool->dp_threads;
1917 pool->dp_threads = t;
1918
1919 /* If someone is waiting for a server thread, wake him up */
1920 cv_signal(&pool->dp_cv);
1921 }
1922
1923 /*
1924 * Remove a server thread from the pool if present.
1925 */
1926 static void
1927 door_server_exit(proc_t *p, kthread_t *t)
1928 {
1929 door_pool_t *pool;
1930 kthread_t **next;
1931 door_server_t *st = DOOR_SERVER(t->t_door);
1932
1933 ASSERT(MUTEX_HELD(&door_knob));
1934 if (st->d_pool != NULL) {
1935 ASSERT(st->d_pool->door_flags & DOOR_PRIVATE);
1936 pool = &st->d_pool->door_servers;
1937 } else {
1938 pool = &p->p_server_threads;
1939 }
1940
1941 next = &pool->dp_threads;
1942 while (*next != NULL) {
1943 if (*next == t) {
1944 *next = DOOR_SERVER(t->t_door)->d_servers;
1945 return;
1946 }
1947 next = &(DOOR_SERVER((*next)->t_door)->d_servers);
1948 }
1949 }
1950
1951 /*
1952 * Lookup the door descriptor. Caller must call releasef when finished
1953 * with associated door.
1954 */
1955 static door_node_t *
1956 door_lookup(int did, file_t **fpp)
1957 {
1958 vnode_t *vp;
1959 file_t *fp;
1960
1961 ASSERT(MUTEX_NOT_HELD(&door_knob));
1962 if ((fp = getf(did)) == NULL)
1963 return (NULL);
1964 /*
1965 * Use the underlying vnode (we may be namefs mounted)
1966 */
1967 if (VOP_REALVP(fp->f_vnode, &vp, NULL))
1968 vp = fp->f_vnode;
1969
1970 if (vp == NULL || vp->v_type != VDOOR) {
1971 releasef(did);
1972 return (NULL);
1973 }
1974
1975 if (fpp)
1976 *fpp = fp;
1977
1978 return (VTOD(vp));
1979 }
1980
1981 /*
1982 * The current thread is exiting, so clean up any pending
1983 * invocation details
1984 */
1985 void
1986 door_slam(void)
1987 {
1988 door_node_t *dp;
1989 door_data_t *dt;
1990 door_client_t *ct;
1991 door_server_t *st;
1992
1993 /*
1994 * If we are an active door server, notify our
1995 * client that we are exiting and revoke our door.
1996 */
1997 if ((dt = door_my_data(0)) == NULL)
1998 return;
1999 ct = DOOR_CLIENT(dt);
2000 st = DOOR_SERVER(dt);
2001
2002 mutex_enter(&door_knob);
2003 for (;;) {
2004 if (DOOR_T_HELD(ct))
2005 cv_wait(&ct->d_cv, &door_knob);
2006 else if (DOOR_T_HELD(st))
2007 cv_wait(&st->d_cv, &door_knob);
2008 else
2009 break; /* neither flag is set */
2010 }
2011 curthread->t_door = NULL;
2012 if ((dp = st->d_active) != NULL) {
2013 kthread_t *t = st->d_caller;
2014 proc_t *p = curproc;
2015
2016 /* Revoke our door if the process is exiting */
2017 if (dp->door_target == p && (p->p_flag & SEXITING)) {
2018 door_list_delete(dp);
2019 dp->door_target = NULL;
2020 dp->door_flags |= DOOR_REVOKED;
2021 if (dp->door_flags & DOOR_PRIVATE)
2022 cv_broadcast(&dp->door_servers.dp_cv);
2023 else
2024 cv_broadcast(&p->p_server_threads.dp_cv);
2025 }
2026
2027 if (t != NULL) {
2028 /*
2029 * Let the caller know we are gone
2030 */
2031 DOOR_CLIENT(t->t_door)->d_error = DOOR_EXIT;
2032 thread_lock(t);
2033 if (t->t_state == TS_SLEEP &&
2034 SOBJ_TYPE(t->t_sobj_ops) == SOBJ_SHUTTLE)
2035 setrun_locked(t);
2036 thread_unlock(t);
2037 }
2038 }
2039 mutex_exit(&door_knob);
2040 if (st->d_pool)
2041 door_unbind_thread(st->d_pool); /* Implicit door_unbind */
2042 kmem_free(dt, sizeof (door_data_t));
2043 }
2044
2045 /*
2046 * Set DOOR_REVOKED for all doors of the current process. This is called
2047 * on exit before all lwp's are being terminated so that door calls will
2048 * return with an error.
2049 */
2050 void
2051 door_revoke_all()
2052 {
2053 door_node_t *dp;
2054 proc_t *p = ttoproc(curthread);
2055
2056 mutex_enter(&door_knob);
2057 for (dp = p->p_door_list; dp != NULL; dp = dp->door_list) {
2058 ASSERT(dp->door_target == p);
2059 dp->door_flags |= DOOR_REVOKED;
2060 if (dp->door_flags & DOOR_PRIVATE)
2061 cv_broadcast(&dp->door_servers.dp_cv);
2062 }
2063 cv_broadcast(&p->p_server_threads.dp_cv);
2064 mutex_exit(&door_knob);
2065 }
2066
2067 /*
2068 * The process is exiting, and all doors it created need to be revoked.
2069 */
2070 void
2071 door_exit(void)
2072 {
2073 door_node_t *dp;
2074 proc_t *p = ttoproc(curthread);
2075
2076 ASSERT(p->p_lwpcnt == 1);
2077 /*
2078 * Walk the list of active doors created by this process and
2079 * revoke them all.
2080 */
2081 mutex_enter(&door_knob);
2082 for (dp = p->p_door_list; dp != NULL; dp = dp->door_list) {
2083 dp->door_target = NULL;
2084 dp->door_flags |= DOOR_REVOKED;
2085 if (dp->door_flags & DOOR_PRIVATE)
2086 cv_broadcast(&dp->door_servers.dp_cv);
2087 }
2088 cv_broadcast(&p->p_server_threads.dp_cv);
2089 /* Clear the list */
2090 p->p_door_list = NULL;
2091
2092 /* Clean up the unref list */
2093 while ((dp = p->p_unref_list) != NULL) {
2094 p->p_unref_list = dp->door_ulist;
2095 dp->door_ulist = NULL;
2096 mutex_exit(&door_knob);
2097 VN_RELE(DTOV(dp));
2098 mutex_enter(&door_knob);
2099 }
2100 mutex_exit(&door_knob);
2101 }
2102
2103
2104 /*
2105 * The process is executing forkall(), and we need to flag threads that
2106 * are bound to a door in the child. This will make the child threads
2107 * return an error to door_return unless they call door_unbind first.
2108 */
2109 void
2110 door_fork(kthread_t *parent, kthread_t *child)
2111 {
2112 door_data_t *pt = parent->t_door;
2113 door_server_t *st = DOOR_SERVER(pt);
2114 door_data_t *dt;
2115
2116 ASSERT(MUTEX_NOT_HELD(&door_knob));
2117 if (pt != NULL && (st->d_pool != NULL || st->d_invbound)) {
2118 /* parent thread is bound to a door */
2119 dt = child->t_door =
2120 kmem_zalloc(sizeof (door_data_t), KM_SLEEP);
2121 DOOR_SERVER(dt)->d_invbound = 1;
2122 }
2123 }
2124
2125 /*
2126 * Deliver queued unrefs to appropriate door server.
2127 */
2128 static int
2129 door_unref(void)
2130 {
2131 door_node_t *dp;
2132 static door_arg_t unref_args = { DOOR_UNREF_DATA, 0, 0, 0, 0, 0 };
2133 proc_t *p = ttoproc(curthread);
2134
2135 /* make sure there's only one unref thread per process */
2136 mutex_enter(&door_knob);
2137 if (p->p_unref_thread) {
2138 mutex_exit(&door_knob);
2139 return (set_errno(EALREADY));
2140 }
2141 p->p_unref_thread = 1;
2142 mutex_exit(&door_knob);
2143
2144 (void) door_my_data(1); /* create info, if necessary */
2145
2146 for (;;) {
2147 mutex_enter(&door_knob);
2148
2149 /* Grab a queued request */
2150 while ((dp = p->p_unref_list) == NULL) {
2151 if (!cv_wait_sig(&p->p_unref_cv, &door_knob)) {
2152 /*
2153 * Interrupted.
2154 * Return so we can finish forkall() or exit().
2155 */
2156 p->p_unref_thread = 0;
2157 mutex_exit(&door_knob);
2158 return (set_errno(EINTR));
2159 }
2160 }
2161 p->p_unref_list = dp->door_ulist;
2162 dp->door_ulist = NULL;
2163 dp->door_flags |= DOOR_UNREF_ACTIVE;
2164 mutex_exit(&door_knob);
2165
2166 (void) door_upcall(DTOV(dp), &unref_args, NULL, SIZE_MAX, 0);
2167
2168 if (unref_args.rbuf != 0) {
2169 kmem_free(unref_args.rbuf, unref_args.rsize);
2170 unref_args.rbuf = NULL;
2171 unref_args.rsize = 0;
2172 }
2173
2174 mutex_enter(&door_knob);
2175 ASSERT(dp->door_flags & DOOR_UNREF_ACTIVE);
2176 dp->door_flags &= ~DOOR_UNREF_ACTIVE;
2177 mutex_exit(&door_knob);
2178 VN_RELE(DTOV(dp));
2179 }
2180 }
2181
2182
2183 /*
2184 * Deliver queued unrefs to kernel door server.
2185 */
2186 /* ARGSUSED */
2187 static void
2188 door_unref_kernel(caddr_t arg)
2189 {
2190 door_node_t *dp;
2191 static door_arg_t unref_args = { DOOR_UNREF_DATA, 0, 0, 0, 0, 0 };
2192 proc_t *p = ttoproc(curthread);
2193 callb_cpr_t cprinfo;
2194
2195 /* should only be one of these */
2196 mutex_enter(&door_knob);
2197 if (p->p_unref_thread) {
2198 mutex_exit(&door_knob);
2199 return;
2200 }
2201 p->p_unref_thread = 1;
2202 mutex_exit(&door_knob);
2203
2204 (void) door_my_data(1); /* make sure we have a door_data_t */
2205
2206 CALLB_CPR_INIT(&cprinfo, &door_knob, callb_generic_cpr, "door_unref");
2207 for (;;) {
2208 mutex_enter(&door_knob);
2209 /* Grab a queued request */
2210 while ((dp = p->p_unref_list) == NULL) {
2211 CALLB_CPR_SAFE_BEGIN(&cprinfo);
2212 cv_wait(&p->p_unref_cv, &door_knob);
2213 CALLB_CPR_SAFE_END(&cprinfo, &door_knob);
2214 }
2215 p->p_unref_list = dp->door_ulist;
2216 dp->door_ulist = NULL;
2217 dp->door_flags |= DOOR_UNREF_ACTIVE;
2218 mutex_exit(&door_knob);
2219
2220 (*(dp->door_pc))(dp->door_data, &unref_args, NULL, NULL, NULL);
2221
2222 mutex_enter(&door_knob);
2223 ASSERT(dp->door_flags & DOOR_UNREF_ACTIVE);
2224 dp->door_flags &= ~DOOR_UNREF_ACTIVE;
2225 mutex_exit(&door_knob);
2226 VN_RELE(DTOV(dp));
2227 }
2228 }
2229
2230
2231 /*
2232 * Queue an unref invocation for processing for the current process
2233 * The door may or may not be revoked at this point.
2234 */
2235 void
2236 door_deliver_unref(door_node_t *d)
2237 {
2238 struct proc *server = d->door_target;
2239
2240 ASSERT(MUTEX_HELD(&door_knob));
2241 ASSERT(d->door_active == 0);
2242
2243 if (server == NULL)
2244 return;
2245 /*
2246 * Create a lwp to deliver unref calls if one isn't already running.
2247 *
2248 * A separate thread is used to deliver unrefs since the current
2249 * thread may be holding resources (e.g. locks) in user land that
2250 * may be needed by the unref processing. This would cause a
2251 * deadlock.
2252 */
2253 if (d->door_flags & DOOR_UNREF_MULTI) {
2254 /* multiple unrefs */
2255 d->door_flags &= ~DOOR_DELAY;
2256 } else {
2257 /* Only 1 unref per door */
2258 d->door_flags &= ~(DOOR_UNREF|DOOR_DELAY);
2259 }
2260 mutex_exit(&door_knob);
2261
2262 /*
2263 * Need to bump the vnode count before putting the door on the
2264 * list so it doesn't get prematurely released by door_unref.
2265 */
2266 VN_HOLD(DTOV(d));
2267
2268 mutex_enter(&door_knob);
2269 /* is this door already on the unref list? */
2270 if (d->door_flags & DOOR_UNREF_MULTI) {
2271 door_node_t *dp;
2272 for (dp = server->p_unref_list; dp != NULL;
2273 dp = dp->door_ulist) {
2274 if (d == dp) {
2275 /* already there, don't need to add another */
2276 mutex_exit(&door_knob);
2277 VN_RELE(DTOV(d));
2278 mutex_enter(&door_knob);
2279 return;
2280 }
2281 }
2282 }
2283 ASSERT(d->door_ulist == NULL);
2284 d->door_ulist = server->p_unref_list;
2285 server->p_unref_list = d;
2286 cv_broadcast(&server->p_unref_cv);
2287 }
2288
2289 /*
2290 * The callers buffer isn't big enough for all of the data/fd's. Allocate
2291 * space in the callers address space for the results and copy the data
2292 * there.
2293 *
2294 * For EOVERFLOW, we must clean up the server's door descriptors.
2295 */
2296 static int
2297 door_overflow(
2298 kthread_t *caller,
2299 caddr_t data_ptr, /* data location */
2300 size_t data_size, /* data size */
2301 door_desc_t *desc_ptr, /* descriptor location */
2302 uint_t desc_num) /* descriptor size */
2303 {
2304 proc_t *callerp = ttoproc(caller);
2305 struct as *as = callerp->p_as;
2306 door_client_t *ct = DOOR_CLIENT(caller->t_door);
2307 caddr_t addr; /* Resulting address in target */
2308 size_t rlen; /* Rounded len */
2309 size_t len;
2310 uint_t i;
2311 size_t ds = desc_num * sizeof (door_desc_t);
2312
2313 ASSERT(MUTEX_NOT_HELD(&door_knob));
2314 ASSERT(DOOR_T_HELD(ct) || ct->d_kernel);
2315
2316 /* Do initial overflow check */
2317 if (!ufcanalloc(callerp, desc_num))
2318 return (EMFILE);
2319
2320 /*
2321 * Allocate space for this stuff in the callers address space
2322 */
2323 rlen = roundup(data_size + ds, PAGESIZE);
2324 as_rangelock(as);
2325 map_addr_proc(&addr, rlen, 0, 1, as->a_userlimit, ttoproc(caller), 0);
2326 if (addr == NULL ||
2327 as_map(as, addr, rlen, segvn_create, zfod_argsp) != 0) {
2328 /* No virtual memory available, or anon mapping failed */
2329 as_rangeunlock(as);
2330 if (!ct->d_kernel && desc_num > 0) {
2331 int error = door_release_fds(desc_ptr, desc_num);
2332 if (error)
2333 return (error);
2334 }
2335 return (EOVERFLOW);
2336 }
2337 as_rangeunlock(as);
2338
2339 if (ct->d_kernel)
2340 goto out;
2341
2342 if (data_size != 0) {
2343 caddr_t src = data_ptr;
2344 caddr_t saddr = addr;
2345
2346 /* Copy any data */
2347 len = data_size;
2348 while (len != 0) {
2349 int amount;
2350 int error;
2351
2352 amount = len > PAGESIZE ? PAGESIZE : len;
2353 if ((error = door_copy(as, src, saddr, amount)) != 0) {
2354 (void) as_unmap(as, addr, rlen);
2355 return (error);
2356 }
2357 saddr += amount;
2358 src += amount;
2359 len -= amount;
2360 }
2361 }
2362 /* Copy any fd's */
2363 if (desc_num != 0) {
2364 door_desc_t *didpp, *start;
2365 struct file **fpp;
2366 int fpp_size;
2367
2368 start = didpp = kmem_alloc(ds, KM_SLEEP);
2369 if (copyin_nowatch(desc_ptr, didpp, ds)) {
2370 kmem_free(start, ds);
2371 (void) as_unmap(as, addr, rlen);
2372 return (EFAULT);
2373 }
2374
2375 fpp_size = desc_num * sizeof (struct file *);
2376 if (fpp_size > ct->d_fpp_size) {
2377 /* make more space */
2378 if (ct->d_fpp_size)
2379 kmem_free(ct->d_fpp, ct->d_fpp_size);
2380 ct->d_fpp_size = fpp_size;
2381 ct->d_fpp = kmem_alloc(ct->d_fpp_size, KM_SLEEP);
2382 }
2383 fpp = ct->d_fpp;
2384
2385 for (i = 0; i < desc_num; i++) {
2386 struct file *fp;
2387 int fd = didpp->d_data.d_desc.d_descriptor;
2388
2389 if (!(didpp->d_attributes & DOOR_DESCRIPTOR) ||
2390 (fp = getf(fd)) == NULL) {
2391 /* close translated references */
2392 door_fp_close(ct->d_fpp, fpp - ct->d_fpp);
2393 /* close untranslated references */
2394 door_fd_rele(didpp, desc_num - i, 0);
2395 kmem_free(start, ds);
2396 (void) as_unmap(as, addr, rlen);
2397 return (EINVAL);
2398 }
2399 mutex_enter(&fp->f_tlock);
2400 fp->f_count++;
2401 mutex_exit(&fp->f_tlock);
2402
2403 *fpp = fp;
2404 releasef(fd);
2405
2406 if (didpp->d_attributes & DOOR_RELEASE) {
2407 /* release passed reference */
2408 (void) closeandsetf(fd, NULL);
2409 }
2410
2411 fpp++; didpp++;
2412 }
2413 kmem_free(start, ds);
2414 }
2415
2416 out:
2417 ct->d_overflow = 1;
2418 ct->d_args.rbuf = addr;
2419 ct->d_args.rsize = rlen;
2420 return (0);
2421 }
2422
2423 /*
2424 * Transfer arguments from the client to the server.
2425 */
2426 static int
2427 door_args(kthread_t *server, int is_private)
2428 {
2429 door_server_t *st = DOOR_SERVER(server->t_door);
2430 door_client_t *ct = DOOR_CLIENT(curthread->t_door);
2431 uint_t ndid;
2432 size_t dsize;
2433 int error;
2434
2435 ASSERT(DOOR_T_HELD(st));
2436 ASSERT(MUTEX_NOT_HELD(&door_knob));
2437
2438 ndid = ct->d_args.desc_num;
2439 if (ndid > door_max_desc)
2440 return (E2BIG);
2441
2442 /*
2443 * Get the stack layout, and fail now if it won't fit.
2444 */
2445 error = door_layout(server, ct->d_args.data_size, ndid, is_private);
2446 if (error != 0)
2447 return (error);
2448
2449 dsize = ndid * sizeof (door_desc_t);
2450 if (ct->d_args.data_size != 0) {
2451 if (ct->d_args.data_size <= door_max_arg) {
2452 /*
2453 * Use a 2 copy method for small amounts of data
2454 *
2455 * Allocate a little more than we need for the
2456 * args, in the hope that the results will fit
2457 * without having to reallocate a buffer
2458 */
2459 ASSERT(ct->d_buf == NULL);
2460 ct->d_bufsize = roundup(ct->d_args.data_size,
2461 DOOR_ROUND);
2462 ct->d_buf = kmem_alloc(ct->d_bufsize, KM_SLEEP);
2463 if (copyin_nowatch(ct->d_args.data_ptr,
2464 ct->d_buf, ct->d_args.data_size) != 0) {
2465 kmem_free(ct->d_buf, ct->d_bufsize);
2466 ct->d_buf = NULL;
2467 ct->d_bufsize = 0;
2468 return (EFAULT);
2469 }
2470 } else {
2471 struct as *as;
2472 caddr_t src;
2473 caddr_t dest;
2474 size_t len = ct->d_args.data_size;
2475 uintptr_t base;
2476
2477 /*
2478 * Use a 1 copy method
2479 */
2480 as = ttoproc(server)->p_as;
2481 src = ct->d_args.data_ptr;
2482
2483 dest = st->d_layout.dl_datap;
2484 base = (uintptr_t)dest;
2485
2486 /*
2487 * Copy data directly into server. We proceed
2488 * downward from the top of the stack, to mimic
2489 * normal stack usage. This allows the guard page
2490 * to stop us before we corrupt anything.
2491 */
2492 while (len != 0) {
2493 uintptr_t start;
2494 uintptr_t end;
2495 uintptr_t offset;
2496 size_t amount;
2497
2498 /*
2499 * Locate the next part to copy.
2500 */
2501 end = base + len;
2502 start = P2ALIGN(end - 1, PAGESIZE);
2503
2504 /*
2505 * if we are on the final (first) page, fix
2506 * up the start position.
2507 */
2508 if (P2ALIGN(base, PAGESIZE) == start)
2509 start = base;
2510
2511 offset = start - base; /* the copy offset */
2512 amount = end - start; /* # bytes to copy */
2513
2514 ASSERT(amount > 0 && amount <= len &&
2515 amount <= PAGESIZE);
2516
2517 error = door_copy(as, src + offset,
2518 dest + offset, amount);
2519 if (error != 0)
2520 return (error);
2521 len -= amount;
2522 }
2523 }
2524 }
2525 /*
2526 * Copyin the door args and translate them into files
2527 */
2528 if (ndid != 0) {
2529 door_desc_t *didpp;
2530 door_desc_t *start;
2531 struct file **fpp;
2532
2533 start = didpp = kmem_alloc(dsize, KM_SLEEP);
2534
2535 if (copyin_nowatch(ct->d_args.desc_ptr, didpp, dsize)) {
2536 kmem_free(start, dsize);
2537 return (EFAULT);
2538 }
2539 ct->d_fpp_size = ndid * sizeof (struct file *);
2540 ct->d_fpp = kmem_alloc(ct->d_fpp_size, KM_SLEEP);
2541 fpp = ct->d_fpp;
2542 while (ndid--) {
2543 struct file *fp;
2544 int fd = didpp->d_data.d_desc.d_descriptor;
2545
2546 /* We only understand file descriptors as passed objs */
2547 if (!(didpp->d_attributes & DOOR_DESCRIPTOR) ||
2548 (fp = getf(fd)) == NULL) {
2549 /* close translated references */
2550 door_fp_close(ct->d_fpp, fpp - ct->d_fpp);
2551 /* close untranslated references */
2552 door_fd_rele(didpp, ndid + 1, 0);
2553 kmem_free(start, dsize);
2554 kmem_free(ct->d_fpp, ct->d_fpp_size);
2555 ct->d_fpp = NULL;
2556 ct->d_fpp_size = 0;
2557 return (EINVAL);
2558 }
2559 /* Hold the fp */
2560 mutex_enter(&fp->f_tlock);
2561 fp->f_count++;
2562 mutex_exit(&fp->f_tlock);
2563
2564 *fpp = fp;
2565 releasef(fd);
2566
2567 if (didpp->d_attributes & DOOR_RELEASE) {
2568 /* release passed reference */
2569 (void) closeandsetf(fd, NULL);
2570 }
2571
2572 fpp++; didpp++;
2573 }
2574 kmem_free(start, dsize);
2575 }
2576 return (0);
2577 }
2578
2579 /*
2580 * Transfer arguments from a user client to a kernel server. This copies in
2581 * descriptors and translates them into door handles. It doesn't touch the
2582 * other data, letting the kernel server deal with that (to avoid needing
2583 * to copy the data twice).
2584 */
2585 static int
2586 door_translate_in(void)
2587 {
2588 door_client_t *ct = DOOR_CLIENT(curthread->t_door);
2589 uint_t ndid;
2590
2591 ASSERT(MUTEX_NOT_HELD(&door_knob));
2592 ndid = ct->d_args.desc_num;
2593 if (ndid > door_max_desc)
2594 return (E2BIG);
2595 /*
2596 * Copyin the door args and translate them into door handles.
2597 */
2598 if (ndid != 0) {
2599 door_desc_t *didpp;
2600 door_desc_t *start;
2601 size_t dsize = ndid * sizeof (door_desc_t);
2602 struct file *fp;
2603
2604 start = didpp = kmem_alloc(dsize, KM_SLEEP);
2605
2606 if (copyin_nowatch(ct->d_args.desc_ptr, didpp, dsize)) {
2607 kmem_free(start, dsize);
2608 return (EFAULT);
2609 }
2610 while (ndid--) {
2611 vnode_t *vp;
2612 int fd = didpp->d_data.d_desc.d_descriptor;
2613
2614 /*
2615 * We only understand file descriptors as passed objs
2616 */
2617 if ((didpp->d_attributes & DOOR_DESCRIPTOR) &&
2618 (fp = getf(fd)) != NULL) {
2619 didpp->d_data.d_handle = FTODH(fp);
2620 /* Hold the door */
2621 door_ki_hold(didpp->d_data.d_handle);
2622
2623 releasef(fd);
2624
2625 if (didpp->d_attributes & DOOR_RELEASE) {
2626 /* release passed reference */
2627 (void) closeandsetf(fd, NULL);
2628 }
2629
2630 if (VOP_REALVP(fp->f_vnode, &vp, NULL))
2631 vp = fp->f_vnode;
2632
2633 /* Set attributes */
2634 didpp->d_attributes = DOOR_HANDLE |
2635 (VTOD(vp)->door_flags & DOOR_ATTR_MASK);
2636 } else {
2637 /* close translated references */
2638 door_fd_close(start, didpp - start);
2639 /* close untranslated references */
2640 door_fd_rele(didpp, ndid + 1, 0);
2641 kmem_free(start, dsize);
2642 return (EINVAL);
2643 }
2644 didpp++;
2645 }
2646 ct->d_args.desc_ptr = start;
2647 }
2648 return (0);
2649 }
2650
2651 /*
2652 * Translate door arguments from kernel to user. This copies the passed
2653 * door handles. It doesn't touch other data. It is used by door_upcall,
2654 * and for data returned by a door_call to a kernel server.
2655 */
2656 static int
2657 door_translate_out(void)
2658 {
2659 door_client_t *ct = DOOR_CLIENT(curthread->t_door);
2660 uint_t ndid;
2661
2662 ASSERT(MUTEX_NOT_HELD(&door_knob));
2663 ndid = ct->d_args.desc_num;
2664 if (ndid > door_max_desc) {
2665 door_fd_rele(ct->d_args.desc_ptr, ndid, 1);
2666 return (E2BIG);
2667 }
2668 /*
2669 * Translate the door args into files
2670 */
2671 if (ndid != 0) {
2672 door_desc_t *didpp = ct->d_args.desc_ptr;
2673 struct file **fpp;
2674
2675 ct->d_fpp_size = ndid * sizeof (struct file *);
2676 fpp = ct->d_fpp = kmem_alloc(ct->d_fpp_size, KM_SLEEP);
2677 while (ndid--) {
2678 struct file *fp = NULL;
2679 int fd = -1;
2680
2681 /*
2682 * We understand file descriptors and door
2683 * handles as passed objs.
2684 */
2685 if (didpp->d_attributes & DOOR_DESCRIPTOR) {
2686 fd = didpp->d_data.d_desc.d_descriptor;
2687 fp = getf(fd);
2688 } else if (didpp->d_attributes & DOOR_HANDLE)
2689 fp = DHTOF(didpp->d_data.d_handle);
2690 if (fp != NULL) {
2691 /* Hold the fp */
2692 mutex_enter(&fp->f_tlock);
2693 fp->f_count++;
2694 mutex_exit(&fp->f_tlock);
2695
2696 *fpp = fp;
2697 if (didpp->d_attributes & DOOR_DESCRIPTOR)
2698 releasef(fd);
2699 if (didpp->d_attributes & DOOR_RELEASE) {
2700 /* release passed reference */
2701 if (fd >= 0)
2702 (void) closeandsetf(fd, NULL);
2703 else
2704 (void) closef(fp);
2705 }
2706 } else {
2707 /* close translated references */
2708 door_fp_close(ct->d_fpp, fpp - ct->d_fpp);
2709 /* close untranslated references */
2710 door_fd_rele(didpp, ndid + 1, 1);
2711 kmem_free(ct->d_fpp, ct->d_fpp_size);
2712 ct->d_fpp = NULL;
2713 ct->d_fpp_size = 0;
2714 return (EINVAL);
2715 }
2716 fpp++; didpp++;
2717 }
2718 }
2719 return (0);
2720 }
2721
2722 /*
2723 * Move the results from the server to the client
2724 */
2725 static int
2726 door_results(kthread_t *caller, caddr_t data_ptr, size_t data_size,
2727 door_desc_t *desc_ptr, uint_t desc_num)
2728 {
2729 door_client_t *ct = DOOR_CLIENT(caller->t_door);
2730 door_upcall_t *dup = ct->d_upcall;
2731 size_t dsize;
2732 size_t rlen;
2733 size_t result_size;
2734
2735 ASSERT(DOOR_T_HELD(ct));
2736 ASSERT(MUTEX_NOT_HELD(&door_knob));
2737
2738 if (ct->d_noresults)
2739 return (E2BIG); /* No results expected */
2740
2741 if (desc_num > door_max_desc)
2742 return (E2BIG); /* Too many descriptors */
2743
2744 dsize = desc_num * sizeof (door_desc_t);
2745 /*
2746 * Check if the results are bigger than the clients buffer
2747 */
2748 if (dsize)
2749 rlen = roundup(data_size, sizeof (door_desc_t));
2750 else
2751 rlen = data_size;
2752 if ((result_size = rlen + dsize) == 0)
2753 return (0);
2754
2755 if (dup != NULL) {
2756 if (desc_num > dup->du_max_descs)
2757 return (EMFILE);
2758
2759 if (data_size > dup->du_max_data)
2760 return (E2BIG);
2761
2762 /*
2763 * Handle upcalls
2764 */
2765 if (ct->d_args.rbuf == NULL || ct->d_args.rsize < result_size) {
2766 /*
2767 * If there's no return buffer or the buffer is too
2768 * small, allocate a new one. The old buffer (if it
2769 * exists) will be freed by the upcall client.
2770 */
2771 if (result_size > door_max_upcall_reply)
2772 return (E2BIG);
2773 ct->d_args.rsize = result_size;
2774 ct->d_args.rbuf = kmem_alloc(result_size, KM_SLEEP);
2775 }
2776 ct->d_args.data_ptr = ct->d_args.rbuf;
2777 if (data_size != 0 &&
2778 copyin_nowatch(data_ptr, ct->d_args.data_ptr,
2779 data_size) != 0)
2780 return (EFAULT);
2781 } else if (result_size > ct->d_args.rsize) {
2782 return (door_overflow(caller, data_ptr, data_size,
2783 desc_ptr, desc_num));
2784 } else if (data_size != 0) {
2785 if (data_size <= door_max_arg) {
2786 /*
2787 * Use a 2 copy method for small amounts of data
2788 */
2789 if (ct->d_buf == NULL) {
2790 ct->d_bufsize = data_size;
2791 ct->d_buf = kmem_alloc(ct->d_bufsize, KM_SLEEP);
2792 } else if (ct->d_bufsize < data_size) {
2793 kmem_free(ct->d_buf, ct->d_bufsize);
2794 ct->d_bufsize = data_size;
2795 ct->d_buf = kmem_alloc(ct->d_bufsize, KM_SLEEP);
2796 }
2797 if (copyin_nowatch(data_ptr, ct->d_buf, data_size) != 0)
2798 return (EFAULT);
2799 } else {
2800 struct as *as = ttoproc(caller)->p_as;
2801 caddr_t dest = ct->d_args.rbuf;
2802 caddr_t src = data_ptr;
2803 size_t len = data_size;
2804
2805 /* Copy data directly into client */
2806 while (len != 0) {
2807 uint_t amount;
2808 uint_t max;
2809 uint_t off;
2810 int error;
2811
2812 off = (uintptr_t)dest & PAGEOFFSET;
2813 if (off)
2814 max = PAGESIZE - off;
2815 else
2816 max = PAGESIZE;
2817 amount = len > max ? max : len;
2818 error = door_copy(as, src, dest, amount);
2819 if (error != 0)
2820 return (error);
2821 dest += amount;
2822 src += amount;
2823 len -= amount;
2824 }
2825 }
2826 }
2827
2828 /*
2829 * Copyin the returned door ids and translate them into door_node_t
2830 */
2831 if (desc_num != 0) {
2832 door_desc_t *start;
2833 door_desc_t *didpp;
2834 struct file **fpp;
2835 size_t fpp_size;
2836 uint_t i;
2837
2838 /* First, check if we would overflow client */
2839 if (!ufcanalloc(ttoproc(caller), desc_num))
2840 return (EMFILE);
2841
2842 start = didpp = kmem_alloc(dsize, KM_SLEEP);
2843 if (copyin_nowatch(desc_ptr, didpp, dsize)) {
2844 kmem_free(start, dsize);
2845 return (EFAULT);
2846 }
2847 fpp_size = desc_num * sizeof (struct file *);
2848 if (fpp_size > ct->d_fpp_size) {
2849 /* make more space */
2850 if (ct->d_fpp_size)
2851 kmem_free(ct->d_fpp, ct->d_fpp_size);
2852 ct->d_fpp_size = fpp_size;
2853 ct->d_fpp = kmem_alloc(fpp_size, KM_SLEEP);
2854 }
2855 fpp = ct->d_fpp;
2856
2857 for (i = 0; i < desc_num; i++) {
2858 struct file *fp;
2859 int fd = didpp->d_data.d_desc.d_descriptor;
2860
2861 /* Only understand file descriptor results */
2862 if (!(didpp->d_attributes & DOOR_DESCRIPTOR) ||
2863 (fp = getf(fd)) == NULL) {
2864 /* close translated references */
2865 door_fp_close(ct->d_fpp, fpp - ct->d_fpp);
2866 /* close untranslated references */
2867 door_fd_rele(didpp, desc_num - i, 0);
2868 kmem_free(start, dsize);
2869 return (EINVAL);
2870 }
2871
2872 mutex_enter(&fp->f_tlock);
2873 fp->f_count++;
2874 mutex_exit(&fp->f_tlock);
2875
2876 *fpp = fp;
2877 releasef(fd);
2878
2879 if (didpp->d_attributes & DOOR_RELEASE) {
2880 /* release passed reference */
2881 (void) closeandsetf(fd, NULL);
2882 }
2883
2884 fpp++; didpp++;
2885 }
2886 kmem_free(start, dsize);
2887 }
2888 return (0);
2889 }
2890
2891 /*
2892 * Close all the descriptors.
2893 */
2894 static void
2895 door_fd_close(door_desc_t *d, uint_t n)
2896 {
2897 uint_t i;
2898
2899 ASSERT(MUTEX_NOT_HELD(&door_knob));
2900 for (i = 0; i < n; i++) {
2901 if (d->d_attributes & DOOR_DESCRIPTOR) {
2902 (void) closeandsetf(
2903 d->d_data.d_desc.d_descriptor, NULL);
2904 } else if (d->d_attributes & DOOR_HANDLE) {
2905 door_ki_rele(d->d_data.d_handle);
2906 }
2907 d++;
2908 }
2909 }
2910
2911 /*
2912 * Close descriptors that have the DOOR_RELEASE attribute set.
2913 */
2914 void
2915 door_fd_rele(door_desc_t *d, uint_t n, int from_kernel)
2916 {
2917 uint_t i;
2918
2919 ASSERT(MUTEX_NOT_HELD(&door_knob));
2920 for (i = 0; i < n; i++) {
2921 if (d->d_attributes & DOOR_RELEASE) {
2922 if (d->d_attributes & DOOR_DESCRIPTOR) {
2923 (void) closeandsetf(
2924 d->d_data.d_desc.d_descriptor, NULL);
2925 } else if (from_kernel &&
2926 (d->d_attributes & DOOR_HANDLE)) {
2927 door_ki_rele(d->d_data.d_handle);
2928 }
2929 }
2930 d++;
2931 }
2932 }
2933
2934 /*
2935 * Copy descriptors into the kernel so we can release any marked
2936 * DOOR_RELEASE.
2937 */
2938 int
2939 door_release_fds(door_desc_t *desc_ptr, uint_t ndesc)
2940 {
2941 size_t dsize;
2942 door_desc_t *didpp;
2943 uint_t desc_num;
2944
2945 ASSERT(MUTEX_NOT_HELD(&door_knob));
2946 ASSERT(ndesc != 0);
2947
2948 desc_num = MIN(ndesc, door_max_desc);
2949
2950 dsize = desc_num * sizeof (door_desc_t);
2951 didpp = kmem_alloc(dsize, KM_SLEEP);
2952
2953 while (ndesc > 0) {
2954 uint_t count = MIN(ndesc, desc_num);
2955
2956 if (copyin_nowatch(desc_ptr, didpp,
2957 count * sizeof (door_desc_t))) {
2958 kmem_free(didpp, dsize);
2959 return (EFAULT);
2960 }
2961 door_fd_rele(didpp, count, 0);
2962
2963 ndesc -= count;
2964 desc_ptr += count;
2965 }
2966 kmem_free(didpp, dsize);
2967 return (0);
2968 }
2969
2970 /*
2971 * Decrement ref count on all the files passed
2972 */
2973 static void
2974 door_fp_close(struct file **fp, uint_t n)
2975 {
2976 uint_t i;
2977
2978 ASSERT(MUTEX_NOT_HELD(&door_knob));
2979
2980 for (i = 0; i < n; i++)
2981 (void) closef(fp[i]);
2982 }
2983
2984 /*
2985 * Copy data from 'src' in current address space to 'dest' in 'as' for 'len'
2986 * bytes.
2987 *
2988 * Performs this using 1 mapin and 1 copy operation.
2989 *
2990 * We really should do more than 1 page at a time to improve
2991 * performance, but for now this is treated as an anomalous condition.
2992 */
2993 static int
2994 door_copy(struct as *as, caddr_t src, caddr_t dest, uint_t len)
2995 {
2996 caddr_t kaddr;
2997 caddr_t rdest;
2998 uint_t off;
2999 page_t **pplist;
3000 page_t *pp = NULL;
3001 int error = 0;
3002
3003 ASSERT(len <= PAGESIZE);
3004 off = (uintptr_t)dest & PAGEOFFSET; /* offset within the page */
3005 rdest = (caddr_t)((uintptr_t)dest &
3006 (uintptr_t)PAGEMASK); /* Page boundary */
3007 ASSERT(off + len <= PAGESIZE);
3008
3009 /*
3010 * Lock down destination page.
3011 */
3012 if (as_pagelock(as, &pplist, rdest, PAGESIZE, S_WRITE))
3013 return (E2BIG);
3014 /*
3015 * Check if we have a shadow page list from as_pagelock. If not,
3016 * we took the slow path and have to find our page struct the hard
3017 * way.
3018 */
3019 if (pplist == NULL) {
3020 pfn_t pfnum;
3021
3022 /* MMU mapping is already locked down */
3023 AS_LOCK_ENTER(as, &as->a_lock, RW_READER);
3024 pfnum = hat_getpfnum(as->a_hat, rdest);
3025 AS_LOCK_EXIT(as, &as->a_lock);
3026
3027 /*
3028 * TODO: The pfn step should not be necessary - need
3029 * a hat_getpp() function.
3030 */
3031 if (pf_is_memory(pfnum)) {
3032 pp = page_numtopp_nolock(pfnum);
3033 ASSERT(pp == NULL || PAGE_LOCKED(pp));
3034 } else
3035 pp = NULL;
3036 if (pp == NULL) {
3037 as_pageunlock(as, pplist, rdest, PAGESIZE, S_WRITE);
3038 return (E2BIG);
3039 }
3040 } else {
3041 pp = *pplist;
3042 }
3043 /*
3044 * Map destination page into kernel address
3045 */
3046 if (kpm_enable)
3047 kaddr = (caddr_t)hat_kpm_mapin(pp, (struct kpme *)NULL);
3048 else
3049 kaddr = (caddr_t)ppmapin(pp, PROT_READ | PROT_WRITE,
3050 (caddr_t)-1);
3051
3052 /*
3053 * Copy from src to dest
3054 */
3055 if (copyin_nowatch(src, kaddr + off, len) != 0)
3056 error = EFAULT;
3057 /*
3058 * Unmap destination page from kernel
3059 */
3060 if (kpm_enable)
3061 hat_kpm_mapout(pp, (struct kpme *)NULL, kaddr);
3062 else
3063 ppmapout(kaddr);
3064 /*
3065 * Unlock destination page
3066 */
3067 as_pageunlock(as, pplist, rdest, PAGESIZE, S_WRITE);
3068 return (error);
3069 }
3070
3071 /*
3072 * General kernel upcall using doors
3073 * Returns 0 on success, errno for failures.
3074 * Caller must have a hold on the door based vnode, and on any
3075 * references passed in desc_ptr. The references are released
3076 * in the event of an error, and passed without duplication
3077 * otherwise. Note that param->rbuf must be 64-bit aligned in
3078 * a 64-bit kernel, since it may be used to store door descriptors
3079 * if they are returned by the server. The caller is responsible
3080 * for holding a reference to the cred passed in.
3081 */
3082 int
3083 door_upcall(vnode_t *vp, door_arg_t *param, struct cred *cred,
3084 size_t max_data, uint_t max_descs)
3085 {
3086 /* Locals */
3087 door_upcall_t *dup;
3088 door_node_t *dp;
3089 kthread_t *server_thread;
3090 int error = 0;
3091 klwp_t *lwp;
3092 door_client_t *ct; /* curthread door_data */
3093 door_server_t *st; /* server thread door_data */
3094 int gotresults = 0;
3095 int cancel_pending;
3096
3097 if (vp->v_type != VDOOR) {
3098 if (param->desc_num)
3099 door_fd_rele(param->desc_ptr, param->desc_num, 1);
3100 return (EINVAL);
3101 }
3102
3103 lwp = ttolwp(curthread);
3104 ct = door_my_client(1);
3105 dp = VTOD(vp); /* Convert to a door_node_t */
3106
3107 dup = kmem_zalloc(sizeof (*dup), KM_SLEEP);
3108 dup->du_cred = (cred != NULL) ? cred : curthread->t_cred;
3109 dup->du_max_data = max_data;
3110 dup->du_max_descs = max_descs;
3111
3112 /*
3113 * This should be done in shuttle_resume(), just before going to
3114 * sleep, but we want to avoid overhead while holding door_knob.
3115 * prstop() is just a no-op if we don't really go to sleep.
3116 * We test not-kernel-address-space for the sake of clustering code.
3117 */
3118 if (lwp && lwp->lwp_nostop == 0 && curproc->p_as != &kas)
3119 prstop(PR_REQUESTED, 0);
3120
3121 mutex_enter(&door_knob);
3122 if (DOOR_INVALID(dp)) {
3123 mutex_exit(&door_knob);
3124 if (param->desc_num)
3125 door_fd_rele(param->desc_ptr, param->desc_num, 1);
3126 error = EBADF;
3127 goto out;
3128 }
3129
3130 if (dp->door_target == &p0) {
3131 /* Can't do an upcall to a kernel server */
3132 mutex_exit(&door_knob);
3133 if (param->desc_num)
3134 door_fd_rele(param->desc_ptr, param->desc_num, 1);
3135 error = EINVAL;
3136 goto out;
3137 }
3138
3139 error = door_check_limits(dp, param, 1);
3140 if (error != 0) {
3141 mutex_exit(&door_knob);
3142 if (param->desc_num)
3143 door_fd_rele(param->desc_ptr, param->desc_num, 1);
3144 goto out;
3145 }
3146
3147 /*
3148 * Get a server thread from the target domain
3149 */
3150 if ((server_thread = door_get_server(dp)) == NULL) {
3151 if (DOOR_INVALID(dp))
3152 error = EBADF;
3153 else
3154 error = EAGAIN;
3155 mutex_exit(&door_knob);
3156 if (param->desc_num)
3157 door_fd_rele(param->desc_ptr, param->desc_num, 1);
3158 goto out;
3159 }
3160
3161 st = DOOR_SERVER(server_thread->t_door);
3162 ct->d_buf = param->data_ptr;
3163 ct->d_bufsize = param->data_size;
3164 ct->d_args = *param; /* structure assignment */
3165
3166 if (ct->d_args.desc_num) {
3167 /*
3168 * Move data from client to server
3169 */
3170 DOOR_T_HOLD(st);
3171 mutex_exit(&door_knob);
3172 error = door_translate_out();
3173 mutex_enter(&door_knob);
3174 DOOR_T_RELEASE(st);
3175 if (error) {
3176 /*
3177 * We're not going to resume this thread after all
3178 */
3179 door_release_server(dp, server_thread);
3180 shuttle_sleep(server_thread);
3181 mutex_exit(&door_knob);
3182 goto out;
3183 }
3184 }
3185
3186 ct->d_upcall = dup;
3187 if (param->rsize == 0)
3188 ct->d_noresults = 1;
3189 else
3190 ct->d_noresults = 0;
3191
3192 dp->door_active++;
3193
3194 ct->d_error = DOOR_WAIT;
3195 st->d_caller = curthread;
3196 st->d_active = dp;
3197
3198 shuttle_resume(server_thread, &door_knob);
3199
3200 mutex_enter(&door_knob);
3201 shuttle_return:
3202 if ((error = ct->d_error) < 0) { /* DOOR_WAIT or DOOR_EXIT */
3203 /*
3204 * Premature wakeup. Find out why (stop, forkall, sig, exit ...)
3205 */
3206 mutex_exit(&door_knob); /* May block in ISSIG */
3207 cancel_pending = 0;
3208 if (lwp && (ISSIG(curthread, FORREAL) || lwp->lwp_sysabort ||
3209 MUSTRETURN(curproc, curthread) ||
3210 (cancel_pending = schedctl_cancel_pending()) != 0)) {
3211 /* Signal, forkall, ... */
3212 if (cancel_pending)
3213 schedctl_cancel_eintr();
3214 lwp->lwp_sysabort = 0;
3215 mutex_enter(&door_knob);
3216 error = EINTR;
3217 /*
3218 * If the server has finished processing our call,
3219 * or exited (calling door_slam()), then d_error
3220 * will have changed. If the server hasn't finished
3221 * yet, d_error will still be DOOR_WAIT, and we
3222 * let it know we are not interested in any
3223 * results by sending a SIGCANCEL, unless the door
3224 * is marked with DOOR_NO_CANCEL.
3225 */
3226 if (ct->d_error == DOOR_WAIT &&
3227 st->d_caller == curthread) {
3228 proc_t *p = ttoproc(server_thread);
3229
3230 st->d_active = NULL;
3231 st->d_caller = NULL;
3232 if (!(dp->door_flags & DOOR_NO_CANCEL)) {
3233 DOOR_T_HOLD(st);
3234 mutex_exit(&door_knob);
3235
3236 mutex_enter(&p->p_lock);
3237 sigtoproc(p, server_thread, SIGCANCEL);
3238 mutex_exit(&p->p_lock);
3239
3240 mutex_enter(&door_knob);
3241 DOOR_T_RELEASE(st);
3242 }
3243 }
3244 } else {
3245 /*
3246 * Return from stop(), server exit...
3247 *
3248 * Note that the server could have done a
3249 * door_return while the client was in stop state
3250 * (ISSIG), in which case the error condition
3251 * is updated by the server.
3252 */
3253 mutex_enter(&door_knob);
3254 if (ct->d_error == DOOR_WAIT) {
3255 /* Still waiting for a reply */
3256 shuttle_swtch(&door_knob);
3257 mutex_enter(&door_knob);
3258 if (lwp)
3259 lwp->lwp_asleep = 0;
3260 goto shuttle_return;
3261 } else if (ct->d_error == DOOR_EXIT) {
3262 /* Server exit */
3263 error = EINTR;
3264 } else {
3265 /* Server did a door_return during ISSIG */
3266 error = ct->d_error;
3267 }
3268 }
3269 /*
3270 * Can't exit if the server is currently copying
3271 * results for me
3272 */
3273 while (DOOR_T_HELD(ct))
3274 cv_wait(&ct->d_cv, &door_knob);
3275
3276 /*
3277 * Find out if results were successfully copied.
3278 */
3279 if (ct->d_error == 0)
3280 gotresults = 1;
3281 }
3282 if (lwp) {
3283 lwp->lwp_asleep = 0; /* /proc */
3284 lwp->lwp_sysabort = 0; /* /proc */
3285 }
3286 if (--dp->door_active == 0 && (dp->door_flags & DOOR_DELAY))
3287 door_deliver_unref(dp);
3288 mutex_exit(&door_knob);
3289
3290 /*
3291 * Translate returned doors (if any)
3292 */
3293
3294 if (ct->d_noresults)
3295 goto out;
3296
3297 if (error) {
3298 /*
3299 * If server returned results successfully, then we've
3300 * been interrupted and may need to clean up.
3301 */
3302 if (gotresults) {
3303 ASSERT(error == EINTR);
3304 door_fp_close(ct->d_fpp, ct->d_args.desc_num);
3305 }
3306 goto out;
3307 }
3308
3309 if (ct->d_args.desc_num) {
3310 struct file **fpp;
3311 door_desc_t *didpp;
3312 vnode_t *vp;
3313 uint_t n = ct->d_args.desc_num;
3314
3315 didpp = ct->d_args.desc_ptr = (door_desc_t *)(ct->d_args.rbuf +
3316 roundup(ct->d_args.data_size, sizeof (door_desc_t)));
3317 fpp = ct->d_fpp;
3318
3319 while (n--) {
3320 struct file *fp;
3321
3322 fp = *fpp;
3323 if (VOP_REALVP(fp->f_vnode, &vp, NULL))
3324 vp = fp->f_vnode;
3325
3326 didpp->d_attributes = DOOR_HANDLE |
3327 (VTOD(vp)->door_flags & DOOR_ATTR_MASK);
3328 didpp->d_data.d_handle = FTODH(fp);
3329
3330 fpp++; didpp++;
3331 }
3332 }
3333
3334 /* on return data is in rbuf */
3335 *param = ct->d_args; /* structure assignment */
3336
3337 out:
3338 kmem_free(dup, sizeof (*dup));
3339
3340 if (ct->d_fpp) {
3341 kmem_free(ct->d_fpp, ct->d_fpp_size);
3342 ct->d_fpp = NULL;
3343 ct->d_fpp_size = 0;
3344 }
3345
3346 ct->d_upcall = NULL;
3347 ct->d_noresults = 0;
3348 ct->d_buf = NULL;
3349 ct->d_bufsize = 0;
3350 return (error);
3351 }
3352
3353 /*
3354 * Add a door to the per-process list of active doors for which the
3355 * process is a server.
3356 */
3357 static void
3358 door_list_insert(door_node_t *dp)
3359 {
3360 proc_t *p = dp->door_target;
3361
3362 ASSERT(MUTEX_HELD(&door_knob));
3363 dp->door_list = p->p_door_list;
3364 p->p_door_list = dp;
3365 }
3366
3367 /*
3368 * Remove a door from the per-process list of active doors.
3369 */
3370 void
3371 door_list_delete(door_node_t *dp)
3372 {
3373 door_node_t **pp;
3374
3375 ASSERT(MUTEX_HELD(&door_knob));
3376 /*
3377 * Find the door in the list. If the door belongs to another process,
3378 * it's OK to use p_door_list since that process can't exit until all
3379 * doors have been taken off the list (see door_exit).
3380 */
3381 pp = &(dp->door_target->p_door_list);
3382 while (*pp != dp)
3383 pp = &((*pp)->door_list);
3384
3385 /* found it, take it off the list */
3386 *pp = dp->door_list;
3387 }
3388
3389
3390 /*
3391 * External kernel interfaces for doors. These functions are available
3392 * outside the doorfs module for use in creating and using doors from
3393 * within the kernel.
3394 */
3395
3396 /*
3397 * door_ki_upcall invokes a user-level door server from the kernel, with
3398 * the credentials associated with curthread.
3399 */
3400 int
3401 door_ki_upcall(door_handle_t dh, door_arg_t *param)
3402 {
3403 return (door_ki_upcall_limited(dh, param, NULL, SIZE_MAX, UINT_MAX));
3404 }
3405
3406 /*
3407 * door_ki_upcall_limited invokes a user-level door server from the
3408 * kernel with the given credentials and reply limits. If the "cred"
3409 * argument is NULL, uses the credentials associated with current
3410 * thread. max_data limits the maximum length of the returned data (the
3411 * client will get E2BIG if they go over), and max_desc limits the
3412 * number of returned descriptors (the client will get EMFILE if they
3413 * go over).
3414 */
3415 int
3416 door_ki_upcall_limited(door_handle_t dh, door_arg_t *param, struct cred *cred,
3417 size_t max_data, uint_t max_desc)
3418 {
3419 file_t *fp = DHTOF(dh);
3420 vnode_t *realvp;
3421
3422 if (VOP_REALVP(fp->f_vnode, &realvp, NULL))
3423 realvp = fp->f_vnode;
3424 return (door_upcall(realvp, param, cred, max_data, max_desc));
3425 }
3426
3427 /*
3428 * Function call to create a "kernel" door server. A kernel door
3429 * server provides a way for a user-level process to invoke a function
3430 * in the kernel through a door_call. From the caller's point of
3431 * view, a kernel door server looks the same as a user-level one
3432 * (except the server pid is 0). Unlike normal door calls, the
3433 * kernel door function is invoked via a normal function call in the
3434 * same thread and context as the caller.
3435 */
3436 int
3437 door_ki_create(void (*pc_cookie)(), void *data_cookie, uint_t attributes,
3438 door_handle_t *dhp)
3439 {
3440 int err;
3441 file_t *fp;
3442
3443 /* no DOOR_PRIVATE */
3444 if ((attributes & ~DOOR_KI_CREATE_MASK) ||
3445 (attributes & (DOOR_UNREF | DOOR_UNREF_MULTI)) ==
3446 (DOOR_UNREF | DOOR_UNREF_MULTI))
3447 return (EINVAL);
3448
3449 err = door_create_common(pc_cookie, data_cookie, attributes,
3450 1, NULL, &fp);
3451 if (err == 0 && (attributes & (DOOR_UNREF | DOOR_UNREF_MULTI)) &&
3452 p0.p_unref_thread == 0) {
3453 /* need to create unref thread for process 0 */
3454 (void) thread_create(NULL, 0, door_unref_kernel, NULL, 0, &p0,
3455 TS_RUN, minclsyspri);
3456 }
3457 if (err == 0) {
3458 *dhp = FTODH(fp);
3459 }
3460 return (err);
3461 }
3462
3463 void
3464 door_ki_hold(door_handle_t dh)
3465 {
3466 file_t *fp = DHTOF(dh);
3467
3468 mutex_enter(&fp->f_tlock);
3469 fp->f_count++;
3470 mutex_exit(&fp->f_tlock);
3471 }
3472
3473 void
3474 door_ki_rele(door_handle_t dh)
3475 {
3476 file_t *fp = DHTOF(dh);
3477
3478 (void) closef(fp);
3479 }
3480
3481 int
3482 door_ki_open(char *pathname, door_handle_t *dhp)
3483 {
3484 file_t *fp;
3485 vnode_t *vp;
3486 int err;
3487
3488 if ((err = lookupname(pathname, UIO_SYSSPACE, FOLLOW, NULL, &vp)) != 0)
3489 return (err);
3490 if (err = VOP_OPEN(&vp, FREAD, kcred, NULL)) {
3491 VN_RELE(vp);
3492 return (err);
3493 }
3494 if (vp->v_type != VDOOR) {
3495 VN_RELE(vp);
3496 return (EINVAL);
3497 }
3498 if ((err = falloc(vp, FREAD | FWRITE, &fp, NULL)) != 0) {
3499 VN_RELE(vp);
3500 return (err);
3501 }
3502 /* falloc returns with f_tlock held on success */
3503 mutex_exit(&fp->f_tlock);
3504 *dhp = FTODH(fp);
3505 return (0);
3506 }
3507
3508 int
3509 door_ki_info(door_handle_t dh, struct door_info *dip)
3510 {
3511 file_t *fp = DHTOF(dh);
3512 vnode_t *vp;
3513
3514 if (VOP_REALVP(fp->f_vnode, &vp, NULL))
3515 vp = fp->f_vnode;
3516 if (vp->v_type != VDOOR)
3517 return (EINVAL);
3518 door_info_common(VTOD(vp), dip, fp);
3519 return (0);
3520 }
3521
3522 door_handle_t
3523 door_ki_lookup(int did)
3524 {
3525 file_t *fp;
3526 door_handle_t dh;
3527
3528 /* is the descriptor really a door? */
3529 if (door_lookup(did, &fp) == NULL)
3530 return (NULL);
3531 /* got the door, put a hold on it and release the fd */
3532 dh = FTODH(fp);
3533 door_ki_hold(dh);
3534 releasef(did);
3535 return (dh);
3536 }
3537
3538 int
3539 door_ki_setparam(door_handle_t dh, int type, size_t val)
3540 {
3541 file_t *fp = DHTOF(dh);
3542 vnode_t *vp;
3543
3544 if (VOP_REALVP(fp->f_vnode, &vp, NULL))
3545 vp = fp->f_vnode;
3546 if (vp->v_type != VDOOR)
3547 return (EINVAL);
3548 return (door_setparam_common(VTOD(vp), 1, type, val));
3549 }
3550
3551 int
3552 door_ki_getparam(door_handle_t dh, int type, size_t *out)
3553 {
3554 file_t *fp = DHTOF(dh);
3555 vnode_t *vp;
3556
3557 if (VOP_REALVP(fp->f_vnode, &vp, NULL))
3558 vp = fp->f_vnode;
3559 if (vp->v_type != VDOOR)
3560 return (EINVAL);
3561 return (door_getparam_common(VTOD(vp), type, out));
3562 }