xref: /freebsd/sys/kern/uipc_mqueue.c (revision c6989859ae9388eeb46a24fe88f9b8d07101c710)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2005 David Xu <davidxu@freebsd.org>
5  * Copyright (c) 2016-2017 Robert N. M. Watson
6  * All rights reserved.
7  *
8  * Portions of this software were developed by BAE Systems, the University of
9  * Cambridge Computer Laboratory, and Memorial University under DARPA/AFRL
10  * contract FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent
11  * Computing (TC) research program.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  */
35 
36 /*
37  * POSIX message queue implementation.
38  *
39  * 1) A mqueue filesystem can be mounted, each message queue appears
40  *    in mounted directory, user can change queue's permission and
41  *    ownership, or remove a queue. Manually creating a file in the
42  *    directory causes a message queue to be created in the kernel with
43  *    default message queue attributes applied and same name used, this
44  *    method is not advocated since mq_open syscall allows user to specify
45  *    different attributes. Also the file system can be mounted multiple
46  *    times at different mount points but shows same contents.
47  *
48  * 2) Standard POSIX message queue API. The syscalls do not use vfs layer,
49  *    but directly operate on internal data structure, this allows user to
50  *    use the IPC facility without having to mount mqueue file system.
51  */
52 
53 #include <sys/cdefs.h>
54 __FBSDID("$FreeBSD$");
55 
56 #include "opt_capsicum.h"
57 
58 #include <sys/param.h>
59 #include <sys/kernel.h>
60 #include <sys/systm.h>
61 #include <sys/limits.h>
62 #include <sys/malloc.h>
63 #include <sys/buf.h>
64 #include <sys/capsicum.h>
65 #include <sys/dirent.h>
66 #include <sys/event.h>
67 #include <sys/eventhandler.h>
68 #include <sys/fcntl.h>
69 #include <sys/file.h>
70 #include <sys/filedesc.h>
71 #include <sys/jail.h>
72 #include <sys/lock.h>
73 #include <sys/module.h>
74 #include <sys/mount.h>
75 #include <sys/mqueue.h>
76 #include <sys/mutex.h>
77 #include <sys/namei.h>
78 #include <sys/posix4.h>
79 #include <sys/poll.h>
80 #include <sys/priv.h>
81 #include <sys/proc.h>
82 #include <sys/queue.h>
83 #include <sys/sysproto.h>
84 #include <sys/stat.h>
85 #include <sys/syscall.h>
86 #include <sys/syscallsubr.h>
87 #include <sys/sysent.h>
88 #include <sys/sx.h>
89 #include <sys/sysctl.h>
90 #include <sys/taskqueue.h>
91 #include <sys/unistd.h>
92 #include <sys/user.h>
93 #include <sys/vnode.h>
94 #include <machine/atomic.h>
95 
96 #include <security/audit/audit.h>
97 
98 FEATURE(p1003_1b_mqueue, "POSIX P1003.1B message queues support");
99 
100 /*
101  * Limits and constants
102  */
103 #define	MQFS_NAMELEN		NAME_MAX
104 #define MQFS_DELEN		(8 + MQFS_NAMELEN)
105 
106 /* node types */
107 typedef enum {
108 	mqfstype_none = 0,
109 	mqfstype_root,
110 	mqfstype_dir,
111 	mqfstype_this,
112 	mqfstype_parent,
113 	mqfstype_file,
114 	mqfstype_symlink,
115 } mqfs_type_t;
116 
117 struct mqfs_node;
118 
119 /*
120  * mqfs_info: describes a mqfs instance
121  */
122 struct mqfs_info {
123 	struct sx		mi_lock;
124 	struct mqfs_node	*mi_root;
125 	struct unrhdr		*mi_unrhdr;
126 };
127 
128 struct mqfs_vdata {
129 	LIST_ENTRY(mqfs_vdata)	mv_link;
130 	struct mqfs_node	*mv_node;
131 	struct vnode		*mv_vnode;
132 	struct task		mv_task;
133 };
134 
135 /*
136  * mqfs_node: describes a node (file or directory) within a mqfs
137  */
138 struct mqfs_node {
139 	char			mn_name[MQFS_NAMELEN+1];
140 	struct mqfs_info	*mn_info;
141 	struct mqfs_node	*mn_parent;
142 	LIST_HEAD(,mqfs_node)	mn_children;
143 	LIST_ENTRY(mqfs_node)	mn_sibling;
144 	LIST_HEAD(,mqfs_vdata)	mn_vnodes;
145 	const void		*mn_pr_root;
146 	int			mn_refcount;
147 	mqfs_type_t		mn_type;
148 	int			mn_deleted;
149 	uint32_t		mn_fileno;
150 	void			*mn_data;
151 	struct timespec		mn_birth;
152 	struct timespec		mn_ctime;
153 	struct timespec		mn_atime;
154 	struct timespec		mn_mtime;
155 	uid_t			mn_uid;
156 	gid_t			mn_gid;
157 	int			mn_mode;
158 };
159 
160 #define	VTON(vp)	(((struct mqfs_vdata *)((vp)->v_data))->mv_node)
161 #define VTOMQ(vp) 	((struct mqueue *)(VTON(vp)->mn_data))
162 #define	VFSTOMQFS(m)	((struct mqfs_info *)((m)->mnt_data))
163 #define	FPTOMQ(fp)	((struct mqueue *)(((struct mqfs_node *) \
164 				(fp)->f_data)->mn_data))
165 
166 TAILQ_HEAD(msgq, mqueue_msg);
167 
168 struct mqueue;
169 
170 struct mqueue_notifier {
171 	LIST_ENTRY(mqueue_notifier)	nt_link;
172 	struct sigevent			nt_sigev;
173 	ksiginfo_t			nt_ksi;
174 	struct proc			*nt_proc;
175 };
176 
177 struct mqueue {
178 	struct mtx	mq_mutex;
179 	int		mq_flags;
180 	long		mq_maxmsg;
181 	long		mq_msgsize;
182 	long		mq_curmsgs;
183 	long		mq_totalbytes;
184 	struct msgq	mq_msgq;
185 	int		mq_receivers;
186 	int		mq_senders;
187 	struct selinfo	mq_rsel;
188 	struct selinfo	mq_wsel;
189 	struct mqueue_notifier	*mq_notifier;
190 };
191 
192 #define	MQ_RSEL		0x01
193 #define	MQ_WSEL		0x02
194 
195 struct mqueue_msg {
196 	TAILQ_ENTRY(mqueue_msg)	msg_link;
197 	unsigned int	msg_prio;
198 	unsigned int	msg_size;
199 	/* following real data... */
200 };
201 
202 static SYSCTL_NODE(_kern, OID_AUTO, mqueue, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
203 	"POSIX real time message queue");
204 
205 static int	default_maxmsg  = 10;
206 static int	default_msgsize = 1024;
207 
208 static int	maxmsg = 100;
209 SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmsg, CTLFLAG_RW,
210     &maxmsg, 0, "Default maximum messages in queue");
211 static int	maxmsgsize = 16384;
212 SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmsgsize, CTLFLAG_RW,
213     &maxmsgsize, 0, "Default maximum message size");
214 static int	maxmq = 100;
215 SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmq, CTLFLAG_RW,
216     &maxmq, 0, "maximum message queues");
217 static int	curmq = 0;
218 SYSCTL_INT(_kern_mqueue, OID_AUTO, curmq, CTLFLAG_RW,
219     &curmq, 0, "current message queue number");
220 static int	unloadable = 0;
221 static MALLOC_DEFINE(M_MQUEUEDATA, "mqdata", "mqueue data");
222 
223 static eventhandler_tag exit_tag;
224 
225 /* Only one instance per-system */
226 static struct mqfs_info		mqfs_data;
227 static uma_zone_t		mqnode_zone;
228 static uma_zone_t		mqueue_zone;
229 static uma_zone_t		mvdata_zone;
230 static uma_zone_t		mqnoti_zone;
231 static struct vop_vector	mqfs_vnodeops;
232 static struct fileops		mqueueops;
233 static unsigned			mqfs_osd_jail_slot;
234 
235 /*
236  * Directory structure construction and manipulation
237  */
238 #ifdef notyet
239 static struct mqfs_node	*mqfs_create_dir(struct mqfs_node *parent,
240 	const char *name, int namelen, struct ucred *cred, int mode);
241 static struct mqfs_node	*mqfs_create_link(struct mqfs_node *parent,
242 	const char *name, int namelen, struct ucred *cred, int mode);
243 #endif
244 
245 static struct mqfs_node	*mqfs_create_file(struct mqfs_node *parent,
246 	const char *name, int namelen, struct ucred *cred, int mode);
247 static int	mqfs_destroy(struct mqfs_node *mn);
248 static void	mqfs_fileno_alloc(struct mqfs_info *mi, struct mqfs_node *mn);
249 static void	mqfs_fileno_free(struct mqfs_info *mi, struct mqfs_node *mn);
250 static int	mqfs_allocv(struct mount *mp, struct vnode **vpp, struct mqfs_node *pn);
251 static int	mqfs_prison_remove(void *obj, void *data);
252 
253 /*
254  * Message queue construction and maniplation
255  */
256 static struct mqueue	*mqueue_alloc(const struct mq_attr *attr);
257 static void	mqueue_free(struct mqueue *mq);
258 static int	mqueue_send(struct mqueue *mq, const char *msg_ptr,
259 			size_t msg_len, unsigned msg_prio, int waitok,
260 			const struct timespec *abs_timeout);
261 static int	mqueue_receive(struct mqueue *mq, char *msg_ptr,
262 			size_t msg_len, unsigned *msg_prio, int waitok,
263 			const struct timespec *abs_timeout);
264 static int	_mqueue_send(struct mqueue *mq, struct mqueue_msg *msg,
265 			int timo);
266 static int	_mqueue_recv(struct mqueue *mq, struct mqueue_msg **msg,
267 			int timo);
268 static void	mqueue_send_notification(struct mqueue *mq);
269 static void	mqueue_fdclose(struct thread *td, int fd, struct file *fp);
270 static void	mq_proc_exit(void *arg, struct proc *p);
271 
272 /*
273  * kqueue filters
274  */
275 static void	filt_mqdetach(struct knote *kn);
276 static int	filt_mqread(struct knote *kn, long hint);
277 static int	filt_mqwrite(struct knote *kn, long hint);
278 
279 struct filterops mq_rfiltops = {
280 	.f_isfd = 1,
281 	.f_detach = filt_mqdetach,
282 	.f_event = filt_mqread,
283 };
284 struct filterops mq_wfiltops = {
285 	.f_isfd = 1,
286 	.f_detach = filt_mqdetach,
287 	.f_event = filt_mqwrite,
288 };
289 
290 /*
291  * Initialize fileno bitmap
292  */
293 static void
294 mqfs_fileno_init(struct mqfs_info *mi)
295 {
296 	struct unrhdr *up;
297 
298 	up = new_unrhdr(1, INT_MAX, NULL);
299 	mi->mi_unrhdr = up;
300 }
301 
302 /*
303  * Tear down fileno bitmap
304  */
305 static void
306 mqfs_fileno_uninit(struct mqfs_info *mi)
307 {
308 	struct unrhdr *up;
309 
310 	up = mi->mi_unrhdr;
311 	mi->mi_unrhdr = NULL;
312 	delete_unrhdr(up);
313 }
314 
315 /*
316  * Allocate a file number
317  */
318 static void
319 mqfs_fileno_alloc(struct mqfs_info *mi, struct mqfs_node *mn)
320 {
321 	/* make sure our parent has a file number */
322 	if (mn->mn_parent && !mn->mn_parent->mn_fileno)
323 		mqfs_fileno_alloc(mi, mn->mn_parent);
324 
325 	switch (mn->mn_type) {
326 	case mqfstype_root:
327 	case mqfstype_dir:
328 	case mqfstype_file:
329 	case mqfstype_symlink:
330 		mn->mn_fileno = alloc_unr(mi->mi_unrhdr);
331 		break;
332 	case mqfstype_this:
333 		KASSERT(mn->mn_parent != NULL,
334 		    ("mqfstype_this node has no parent"));
335 		mn->mn_fileno = mn->mn_parent->mn_fileno;
336 		break;
337 	case mqfstype_parent:
338 		KASSERT(mn->mn_parent != NULL,
339 		    ("mqfstype_parent node has no parent"));
340 		if (mn->mn_parent == mi->mi_root) {
341 			mn->mn_fileno = mn->mn_parent->mn_fileno;
342 			break;
343 		}
344 		KASSERT(mn->mn_parent->mn_parent != NULL,
345 		    ("mqfstype_parent node has no grandparent"));
346 		mn->mn_fileno = mn->mn_parent->mn_parent->mn_fileno;
347 		break;
348 	default:
349 		KASSERT(0,
350 		    ("mqfs_fileno_alloc() called for unknown type node: %d",
351 			mn->mn_type));
352 		break;
353 	}
354 }
355 
356 /*
357  * Release a file number
358  */
359 static void
360 mqfs_fileno_free(struct mqfs_info *mi, struct mqfs_node *mn)
361 {
362 	switch (mn->mn_type) {
363 	case mqfstype_root:
364 	case mqfstype_dir:
365 	case mqfstype_file:
366 	case mqfstype_symlink:
367 		free_unr(mi->mi_unrhdr, mn->mn_fileno);
368 		break;
369 	case mqfstype_this:
370 	case mqfstype_parent:
371 		/* ignore these, as they don't "own" their file number */
372 		break;
373 	default:
374 		KASSERT(0,
375 		    ("mqfs_fileno_free() called for unknown type node: %d",
376 			mn->mn_type));
377 		break;
378 	}
379 }
380 
381 static __inline struct mqfs_node *
382 mqnode_alloc(void)
383 {
384 	return uma_zalloc(mqnode_zone, M_WAITOK | M_ZERO);
385 }
386 
387 static __inline void
388 mqnode_free(struct mqfs_node *node)
389 {
390 	uma_zfree(mqnode_zone, node);
391 }
392 
393 static __inline void
394 mqnode_addref(struct mqfs_node *node)
395 {
396 	atomic_add_int(&node->mn_refcount, 1);
397 }
398 
399 static __inline void
400 mqnode_release(struct mqfs_node *node)
401 {
402 	struct mqfs_info *mqfs;
403 	int old, exp;
404 
405 	mqfs = node->mn_info;
406 	old = atomic_fetchadd_int(&node->mn_refcount, -1);
407 	if (node->mn_type == mqfstype_dir ||
408 	    node->mn_type == mqfstype_root)
409 		exp = 3; /* include . and .. */
410 	else
411 		exp = 1;
412 	if (old == exp) {
413 		int locked = sx_xlocked(&mqfs->mi_lock);
414 		if (!locked)
415 			sx_xlock(&mqfs->mi_lock);
416 		mqfs_destroy(node);
417 		if (!locked)
418 			sx_xunlock(&mqfs->mi_lock);
419 	}
420 }
421 
422 /*
423  * Add a node to a directory
424  */
425 static int
426 mqfs_add_node(struct mqfs_node *parent, struct mqfs_node *node)
427 {
428 	KASSERT(parent != NULL, ("%s(): parent is NULL", __func__));
429 	KASSERT(parent->mn_info != NULL,
430 	    ("%s(): parent has no mn_info", __func__));
431 	KASSERT(parent->mn_type == mqfstype_dir ||
432 	    parent->mn_type == mqfstype_root,
433 	    ("%s(): parent is not a directory", __func__));
434 
435 	node->mn_info = parent->mn_info;
436 	node->mn_parent = parent;
437 	LIST_INIT(&node->mn_children);
438 	LIST_INIT(&node->mn_vnodes);
439 	LIST_INSERT_HEAD(&parent->mn_children, node, mn_sibling);
440 	mqnode_addref(parent);
441 	return (0);
442 }
443 
444 static struct mqfs_node *
445 mqfs_create_node(const char *name, int namelen, struct ucred *cred, int mode,
446 	int nodetype)
447 {
448 	struct mqfs_node *node;
449 
450 	node = mqnode_alloc();
451 	strncpy(node->mn_name, name, namelen);
452 	node->mn_pr_root = cred->cr_prison->pr_root;
453 	node->mn_type = nodetype;
454 	node->mn_refcount = 1;
455 	vfs_timestamp(&node->mn_birth);
456 	node->mn_ctime = node->mn_atime = node->mn_mtime
457 		= node->mn_birth;
458 	node->mn_uid = cred->cr_uid;
459 	node->mn_gid = cred->cr_gid;
460 	node->mn_mode = mode;
461 	return (node);
462 }
463 
464 /*
465  * Create a file
466  */
467 static struct mqfs_node *
468 mqfs_create_file(struct mqfs_node *parent, const char *name, int namelen,
469 	struct ucred *cred, int mode)
470 {
471 	struct mqfs_node *node;
472 
473 	node = mqfs_create_node(name, namelen, cred, mode, mqfstype_file);
474 	if (mqfs_add_node(parent, node) != 0) {
475 		mqnode_free(node);
476 		return (NULL);
477 	}
478 	return (node);
479 }
480 
481 /*
482  * Add . and .. to a directory
483  */
484 static int
485 mqfs_fixup_dir(struct mqfs_node *parent)
486 {
487 	struct mqfs_node *dir;
488 
489 	dir = mqnode_alloc();
490 	dir->mn_name[0] = '.';
491 	dir->mn_type = mqfstype_this;
492 	dir->mn_refcount = 1;
493 	if (mqfs_add_node(parent, dir) != 0) {
494 		mqnode_free(dir);
495 		return (-1);
496 	}
497 
498 	dir = mqnode_alloc();
499 	dir->mn_name[0] = dir->mn_name[1] = '.';
500 	dir->mn_type = mqfstype_parent;
501 	dir->mn_refcount = 1;
502 
503 	if (mqfs_add_node(parent, dir) != 0) {
504 		mqnode_free(dir);
505 		return (-1);
506 	}
507 
508 	return (0);
509 }
510 
511 #ifdef notyet
512 
513 /*
514  * Create a directory
515  */
516 static struct mqfs_node *
517 mqfs_create_dir(struct mqfs_node *parent, const char *name, int namelen,
518 	struct ucred *cred, int mode)
519 {
520 	struct mqfs_node *node;
521 
522 	node = mqfs_create_node(name, namelen, cred, mode, mqfstype_dir);
523 	if (mqfs_add_node(parent, node) != 0) {
524 		mqnode_free(node);
525 		return (NULL);
526 	}
527 
528 	if (mqfs_fixup_dir(node) != 0) {
529 		mqfs_destroy(node);
530 		return (NULL);
531 	}
532 	return (node);
533 }
534 
535 /*
536  * Create a symlink
537  */
538 static struct mqfs_node *
539 mqfs_create_link(struct mqfs_node *parent, const char *name, int namelen,
540 	struct ucred *cred, int mode)
541 {
542 	struct mqfs_node *node;
543 
544 	node = mqfs_create_node(name, namelen, cred, mode, mqfstype_symlink);
545 	if (mqfs_add_node(parent, node) != 0) {
546 		mqnode_free(node);
547 		return (NULL);
548 	}
549 	return (node);
550 }
551 
552 #endif
553 
554 /*
555  * Destroy a node or a tree of nodes
556  */
557 static int
558 mqfs_destroy(struct mqfs_node *node)
559 {
560 	struct mqfs_node *parent;
561 
562 	KASSERT(node != NULL,
563 	    ("%s(): node is NULL", __func__));
564 	KASSERT(node->mn_info != NULL,
565 	    ("%s(): node has no mn_info", __func__));
566 
567 	/* destroy children */
568 	if (node->mn_type == mqfstype_dir || node->mn_type == mqfstype_root)
569 		while (! LIST_EMPTY(&node->mn_children))
570 			mqfs_destroy(LIST_FIRST(&node->mn_children));
571 
572 	/* unlink from parent */
573 	if ((parent = node->mn_parent) != NULL) {
574 		KASSERT(parent->mn_info == node->mn_info,
575 		    ("%s(): parent has different mn_info", __func__));
576 		LIST_REMOVE(node, mn_sibling);
577 	}
578 
579 	if (node->mn_fileno != 0)
580 		mqfs_fileno_free(node->mn_info, node);
581 	if (node->mn_data != NULL)
582 		mqueue_free(node->mn_data);
583 	mqnode_free(node);
584 	return (0);
585 }
586 
587 /*
588  * Mount a mqfs instance
589  */
590 static int
591 mqfs_mount(struct mount *mp)
592 {
593 	struct statfs *sbp;
594 
595 	if (mp->mnt_flag & MNT_UPDATE)
596 		return (EOPNOTSUPP);
597 
598 	mp->mnt_data = &mqfs_data;
599 	MNT_ILOCK(mp);
600 	mp->mnt_flag |= MNT_LOCAL;
601 	MNT_IUNLOCK(mp);
602 	vfs_getnewfsid(mp);
603 
604 	sbp = &mp->mnt_stat;
605 	vfs_mountedfrom(mp, "mqueue");
606 	sbp->f_bsize = PAGE_SIZE;
607 	sbp->f_iosize = PAGE_SIZE;
608 	sbp->f_blocks = 1;
609 	sbp->f_bfree = 0;
610 	sbp->f_bavail = 0;
611 	sbp->f_files = 1;
612 	sbp->f_ffree = 0;
613 	return (0);
614 }
615 
616 /*
617  * Unmount a mqfs instance
618  */
619 static int
620 mqfs_unmount(struct mount *mp, int mntflags)
621 {
622 	int error;
623 
624 	error = vflush(mp, 0, (mntflags & MNT_FORCE) ?  FORCECLOSE : 0,
625 	    curthread);
626 	return (error);
627 }
628 
629 /*
630  * Return a root vnode
631  */
632 static int
633 mqfs_root(struct mount *mp, int flags, struct vnode **vpp)
634 {
635 	struct mqfs_info *mqfs;
636 	int ret;
637 
638 	mqfs = VFSTOMQFS(mp);
639 	ret = mqfs_allocv(mp, vpp, mqfs->mi_root);
640 	return (ret);
641 }
642 
643 /*
644  * Return filesystem stats
645  */
646 static int
647 mqfs_statfs(struct mount *mp, struct statfs *sbp)
648 {
649 	/* XXX update statistics */
650 	return (0);
651 }
652 
653 /*
654  * Initialize a mqfs instance
655  */
656 static int
657 mqfs_init(struct vfsconf *vfc)
658 {
659 	struct mqfs_node *root;
660 	struct mqfs_info *mi;
661 	osd_method_t methods[PR_MAXMETHOD] = {
662 	    [PR_METHOD_REMOVE] = mqfs_prison_remove,
663 	};
664 
665 	mqnode_zone = uma_zcreate("mqnode", sizeof(struct mqfs_node),
666 		NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
667 	mqueue_zone = uma_zcreate("mqueue", sizeof(struct mqueue),
668 		NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
669 	mvdata_zone = uma_zcreate("mvdata",
670 		sizeof(struct mqfs_vdata), NULL, NULL, NULL,
671 		NULL, UMA_ALIGN_PTR, 0);
672 	mqnoti_zone = uma_zcreate("mqnotifier", sizeof(struct mqueue_notifier),
673 		NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
674 	mi = &mqfs_data;
675 	sx_init(&mi->mi_lock, "mqfs lock");
676 	/* set up the root diretory */
677 	root = mqfs_create_node("/", 1, curthread->td_ucred, 01777,
678 		mqfstype_root);
679 	root->mn_info = mi;
680 	LIST_INIT(&root->mn_children);
681 	LIST_INIT(&root->mn_vnodes);
682 	mi->mi_root = root;
683 	mqfs_fileno_init(mi);
684 	mqfs_fileno_alloc(mi, root);
685 	mqfs_fixup_dir(root);
686 	exit_tag = EVENTHANDLER_REGISTER(process_exit, mq_proc_exit, NULL,
687 	    EVENTHANDLER_PRI_ANY);
688 	mq_fdclose = mqueue_fdclose;
689 	p31b_setcfg(CTL_P1003_1B_MESSAGE_PASSING, _POSIX_MESSAGE_PASSING);
690 	mqfs_osd_jail_slot = osd_jail_register(NULL, methods);
691 	return (0);
692 }
693 
694 /*
695  * Destroy a mqfs instance
696  */
697 static int
698 mqfs_uninit(struct vfsconf *vfc)
699 {
700 	struct mqfs_info *mi;
701 
702 	if (!unloadable)
703 		return (EOPNOTSUPP);
704 	osd_jail_deregister(mqfs_osd_jail_slot);
705 	EVENTHANDLER_DEREGISTER(process_exit, exit_tag);
706 	mi = &mqfs_data;
707 	mqfs_destroy(mi->mi_root);
708 	mi->mi_root = NULL;
709 	mqfs_fileno_uninit(mi);
710 	sx_destroy(&mi->mi_lock);
711 	uma_zdestroy(mqnode_zone);
712 	uma_zdestroy(mqueue_zone);
713 	uma_zdestroy(mvdata_zone);
714 	uma_zdestroy(mqnoti_zone);
715 	return (0);
716 }
717 
718 /*
719  * task routine
720  */
721 static void
722 do_recycle(void *context, int pending __unused)
723 {
724 	struct vnode *vp = (struct vnode *)context;
725 
726 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
727 	vrecycle(vp);
728 	VOP_UNLOCK(vp);
729 	vdrop(vp);
730 }
731 
732 /*
733  * Allocate a vnode
734  */
735 static int
736 mqfs_allocv(struct mount *mp, struct vnode **vpp, struct mqfs_node *pn)
737 {
738 	struct mqfs_vdata *vd;
739 	struct mqfs_info  *mqfs;
740 	struct vnode *newvpp;
741 	int error;
742 
743 	mqfs = pn->mn_info;
744 	*vpp = NULL;
745 	sx_xlock(&mqfs->mi_lock);
746 	LIST_FOREACH(vd, &pn->mn_vnodes, mv_link) {
747 		if (vd->mv_vnode->v_mount == mp) {
748 			vhold(vd->mv_vnode);
749 			break;
750 		}
751 	}
752 
753 	if (vd != NULL) {
754 found:
755 		*vpp = vd->mv_vnode;
756 		sx_xunlock(&mqfs->mi_lock);
757 		error = vget(*vpp, LK_RETRY | LK_EXCLUSIVE);
758 		vdrop(*vpp);
759 		return (error);
760 	}
761 	sx_xunlock(&mqfs->mi_lock);
762 
763 	error = getnewvnode("mqueue", mp, &mqfs_vnodeops, &newvpp);
764 	if (error)
765 		return (error);
766 	vn_lock(newvpp, LK_EXCLUSIVE | LK_RETRY);
767 	error = insmntque(newvpp, mp);
768 	if (error != 0)
769 		return (error);
770 
771 	sx_xlock(&mqfs->mi_lock);
772 	/*
773 	 * Check if it has already been allocated
774 	 * while we were blocked.
775 	 */
776 	LIST_FOREACH(vd, &pn->mn_vnodes, mv_link) {
777 		if (vd->mv_vnode->v_mount == mp) {
778 			vhold(vd->mv_vnode);
779 			sx_xunlock(&mqfs->mi_lock);
780 
781 			vgone(newvpp);
782 			vput(newvpp);
783 			goto found;
784 		}
785 	}
786 
787 	*vpp = newvpp;
788 
789 	vd = uma_zalloc(mvdata_zone, M_WAITOK);
790 	(*vpp)->v_data = vd;
791 	vd->mv_vnode = *vpp;
792 	vd->mv_node = pn;
793 	TASK_INIT(&vd->mv_task, 0, do_recycle, *vpp);
794 	LIST_INSERT_HEAD(&pn->mn_vnodes, vd, mv_link);
795 	mqnode_addref(pn);
796 	switch (pn->mn_type) {
797 	case mqfstype_root:
798 		(*vpp)->v_vflag = VV_ROOT;
799 		/* fall through */
800 	case mqfstype_dir:
801 	case mqfstype_this:
802 	case mqfstype_parent:
803 		(*vpp)->v_type = VDIR;
804 		break;
805 	case mqfstype_file:
806 		(*vpp)->v_type = VREG;
807 		break;
808 	case mqfstype_symlink:
809 		(*vpp)->v_type = VLNK;
810 		break;
811 	case mqfstype_none:
812 		KASSERT(0, ("mqfs_allocf called for null node\n"));
813 	default:
814 		panic("%s has unexpected type: %d", pn->mn_name, pn->mn_type);
815 	}
816 	sx_xunlock(&mqfs->mi_lock);
817 	return (0);
818 }
819 
820 /*
821  * Search a directory entry
822  */
823 static struct mqfs_node *
824 mqfs_search(struct mqfs_node *pd, const char *name, int len, struct ucred *cred)
825 {
826 	struct mqfs_node *pn;
827 	const void *pr_root;
828 
829 	sx_assert(&pd->mn_info->mi_lock, SX_LOCKED);
830 	pr_root = cred->cr_prison->pr_root;
831 	LIST_FOREACH(pn, &pd->mn_children, mn_sibling) {
832 		/* Only match names within the same prison root directory */
833 		if ((pn->mn_pr_root == NULL || pn->mn_pr_root == pr_root) &&
834 		    strncmp(pn->mn_name, name, len) == 0 &&
835 		    pn->mn_name[len] == '\0')
836 			return (pn);
837 	}
838 	return (NULL);
839 }
840 
841 /*
842  * Look up a file or directory.
843  */
844 static int
845 mqfs_lookupx(struct vop_cachedlookup_args *ap)
846 {
847 	struct componentname *cnp;
848 	struct vnode *dvp, **vpp;
849 	struct mqfs_node *pd;
850 	struct mqfs_node *pn;
851 	struct mqfs_info *mqfs;
852 	int nameiop, flags, error, namelen;
853 	char *pname;
854 	struct thread *td;
855 
856 	cnp = ap->a_cnp;
857 	vpp = ap->a_vpp;
858 	dvp = ap->a_dvp;
859 	pname = cnp->cn_nameptr;
860 	namelen = cnp->cn_namelen;
861 	td = cnp->cn_thread;
862 	flags = cnp->cn_flags;
863 	nameiop = cnp->cn_nameiop;
864 	pd = VTON(dvp);
865 	pn = NULL;
866 	mqfs = pd->mn_info;
867 	*vpp = NULLVP;
868 
869 	if (dvp->v_type != VDIR)
870 		return (ENOTDIR);
871 
872 	error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, cnp->cn_thread);
873 	if (error)
874 		return (error);
875 
876 	/* shortcut: check if the name is too long */
877 	if (cnp->cn_namelen >= MQFS_NAMELEN)
878 		return (ENOENT);
879 
880 	/* self */
881 	if (namelen == 1 && pname[0] == '.') {
882 		if ((flags & ISLASTCN) && nameiop != LOOKUP)
883 			return (EINVAL);
884 		pn = pd;
885 		*vpp = dvp;
886 		VREF(dvp);
887 		return (0);
888 	}
889 
890 	/* parent */
891 	if (cnp->cn_flags & ISDOTDOT) {
892 		if (dvp->v_vflag & VV_ROOT)
893 			return (EIO);
894 		if ((flags & ISLASTCN) && nameiop != LOOKUP)
895 			return (EINVAL);
896 		VOP_UNLOCK(dvp);
897 		KASSERT(pd->mn_parent, ("non-root directory has no parent"));
898 		pn = pd->mn_parent;
899 		error = mqfs_allocv(dvp->v_mount, vpp, pn);
900 		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
901 		return (error);
902 	}
903 
904 	/* named node */
905 	sx_xlock(&mqfs->mi_lock);
906 	pn = mqfs_search(pd, pname, namelen, cnp->cn_cred);
907 	if (pn != NULL)
908 		mqnode_addref(pn);
909 	sx_xunlock(&mqfs->mi_lock);
910 
911 	/* found */
912 	if (pn != NULL) {
913 		/* DELETE */
914 		if (nameiop == DELETE && (flags & ISLASTCN)) {
915 			error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td);
916 			if (error) {
917 				mqnode_release(pn);
918 				return (error);
919 			}
920 			if (*vpp == dvp) {
921 				VREF(dvp);
922 				*vpp = dvp;
923 				mqnode_release(pn);
924 				return (0);
925 			}
926 		}
927 
928 		/* allocate vnode */
929 		error = mqfs_allocv(dvp->v_mount, vpp, pn);
930 		mqnode_release(pn);
931 		if (error == 0 && cnp->cn_flags & MAKEENTRY)
932 			cache_enter(dvp, *vpp, cnp);
933 		return (error);
934 	}
935 
936 	/* not found */
937 
938 	/* will create a new entry in the directory ? */
939 	if ((nameiop == CREATE || nameiop == RENAME) && (flags & LOCKPARENT)
940 	    && (flags & ISLASTCN)) {
941 		error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td);
942 		if (error)
943 			return (error);
944 		cnp->cn_flags |= SAVENAME;
945 		return (EJUSTRETURN);
946 	}
947 	return (ENOENT);
948 }
949 
950 #if 0
951 struct vop_lookup_args {
952 	struct vop_generic_args a_gen;
953 	struct vnode *a_dvp;
954 	struct vnode **a_vpp;
955 	struct componentname *a_cnp;
956 };
957 #endif
958 
959 /*
960  * vnode lookup operation
961  */
962 static int
963 mqfs_lookup(struct vop_cachedlookup_args *ap)
964 {
965 	int rc;
966 
967 	rc = mqfs_lookupx(ap);
968 	return (rc);
969 }
970 
971 #if 0
972 struct vop_create_args {
973 	struct vnode *a_dvp;
974 	struct vnode **a_vpp;
975 	struct componentname *a_cnp;
976 	struct vattr *a_vap;
977 };
978 #endif
979 
980 /*
981  * vnode creation operation
982  */
983 static int
984 mqfs_create(struct vop_create_args *ap)
985 {
986 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount);
987 	struct componentname *cnp = ap->a_cnp;
988 	struct mqfs_node *pd;
989 	struct mqfs_node *pn;
990 	struct mqueue *mq;
991 	int error;
992 
993 	pd = VTON(ap->a_dvp);
994 	if (pd->mn_type != mqfstype_root && pd->mn_type != mqfstype_dir)
995 		return (ENOTDIR);
996 	mq = mqueue_alloc(NULL);
997 	if (mq == NULL)
998 		return (EAGAIN);
999 	sx_xlock(&mqfs->mi_lock);
1000 	if ((cnp->cn_flags & HASBUF) == 0)
1001 		panic("%s: no name", __func__);
1002 	pn = mqfs_create_file(pd, cnp->cn_nameptr, cnp->cn_namelen,
1003 		cnp->cn_cred, ap->a_vap->va_mode);
1004 	if (pn == NULL) {
1005 		sx_xunlock(&mqfs->mi_lock);
1006 		error = ENOSPC;
1007 	} else {
1008 		mqnode_addref(pn);
1009 		sx_xunlock(&mqfs->mi_lock);
1010 		error = mqfs_allocv(ap->a_dvp->v_mount, ap->a_vpp, pn);
1011 		mqnode_release(pn);
1012 		if (error)
1013 			mqfs_destroy(pn);
1014 		else
1015 			pn->mn_data = mq;
1016 	}
1017 	if (error)
1018 		mqueue_free(mq);
1019 	return (error);
1020 }
1021 
1022 /*
1023  * Remove an entry
1024  */
1025 static
1026 int do_unlink(struct mqfs_node *pn, struct ucred *ucred)
1027 {
1028 	struct mqfs_node *parent;
1029 	struct mqfs_vdata *vd;
1030 	int error = 0;
1031 
1032 	sx_assert(&pn->mn_info->mi_lock, SX_LOCKED);
1033 
1034 	if (ucred->cr_uid != pn->mn_uid &&
1035 	    (error = priv_check_cred(ucred, PRIV_MQ_ADMIN)) != 0)
1036 		error = EACCES;
1037 	else if (!pn->mn_deleted) {
1038 		parent = pn->mn_parent;
1039 		pn->mn_parent = NULL;
1040 		pn->mn_deleted = 1;
1041 		LIST_REMOVE(pn, mn_sibling);
1042 		LIST_FOREACH(vd, &pn->mn_vnodes, mv_link) {
1043 			cache_purge(vd->mv_vnode);
1044 			vhold(vd->mv_vnode);
1045 			taskqueue_enqueue(taskqueue_thread, &vd->mv_task);
1046 		}
1047 		mqnode_release(pn);
1048 		mqnode_release(parent);
1049 	} else
1050 		error = ENOENT;
1051 	return (error);
1052 }
1053 
1054 #if 0
1055 struct vop_remove_args {
1056 	struct vnode *a_dvp;
1057 	struct vnode *a_vp;
1058 	struct componentname *a_cnp;
1059 };
1060 #endif
1061 
1062 /*
1063  * vnode removal operation
1064  */
1065 static int
1066 mqfs_remove(struct vop_remove_args *ap)
1067 {
1068 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount);
1069 	struct mqfs_node *pn;
1070 	int error;
1071 
1072 	if (ap->a_vp->v_type == VDIR)
1073                 return (EPERM);
1074 	pn = VTON(ap->a_vp);
1075 	sx_xlock(&mqfs->mi_lock);
1076 	error = do_unlink(pn, ap->a_cnp->cn_cred);
1077 	sx_xunlock(&mqfs->mi_lock);
1078 	return (error);
1079 }
1080 
1081 #if 0
1082 struct vop_inactive_args {
1083 	struct vnode *a_vp;
1084 	struct thread *a_td;
1085 };
1086 #endif
1087 
1088 static int
1089 mqfs_inactive(struct vop_inactive_args *ap)
1090 {
1091 	struct mqfs_node *pn = VTON(ap->a_vp);
1092 
1093 	if (pn->mn_deleted)
1094 		vrecycle(ap->a_vp);
1095 	return (0);
1096 }
1097 
1098 #if 0
1099 struct vop_reclaim_args {
1100 	struct vop_generic_args a_gen;
1101 	struct vnode *a_vp;
1102 };
1103 #endif
1104 
1105 static int
1106 mqfs_reclaim(struct vop_reclaim_args *ap)
1107 {
1108 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_vp->v_mount);
1109 	struct vnode *vp = ap->a_vp;
1110 	struct mqfs_node *pn;
1111 	struct mqfs_vdata *vd;
1112 
1113 	vd = vp->v_data;
1114 	pn = vd->mv_node;
1115 	sx_xlock(&mqfs->mi_lock);
1116 	vp->v_data = NULL;
1117 	LIST_REMOVE(vd, mv_link);
1118 	uma_zfree(mvdata_zone, vd);
1119 	mqnode_release(pn);
1120 	sx_xunlock(&mqfs->mi_lock);
1121 	return (0);
1122 }
1123 
1124 #if 0
1125 struct vop_open_args {
1126 	struct vop_generic_args a_gen;
1127 	struct vnode *a_vp;
1128 	int a_mode;
1129 	struct ucred *a_cred;
1130 	struct thread *a_td;
1131 	struct file *a_fp;
1132 };
1133 #endif
1134 
1135 static int
1136 mqfs_open(struct vop_open_args *ap)
1137 {
1138 	return (0);
1139 }
1140 
1141 #if 0
1142 struct vop_close_args {
1143 	struct vop_generic_args a_gen;
1144 	struct vnode *a_vp;
1145 	int a_fflag;
1146 	struct ucred *a_cred;
1147 	struct thread *a_td;
1148 };
1149 #endif
1150 
1151 static int
1152 mqfs_close(struct vop_close_args *ap)
1153 {
1154 	return (0);
1155 }
1156 
1157 #if 0
1158 struct vop_access_args {
1159 	struct vop_generic_args a_gen;
1160 	struct vnode *a_vp;
1161 	accmode_t a_accmode;
1162 	struct ucred *a_cred;
1163 	struct thread *a_td;
1164 };
1165 #endif
1166 
1167 /*
1168  * Verify permissions
1169  */
1170 static int
1171 mqfs_access(struct vop_access_args *ap)
1172 {
1173 	struct vnode *vp = ap->a_vp;
1174 	struct vattr vattr;
1175 	int error;
1176 
1177 	error = VOP_GETATTR(vp, &vattr, ap->a_cred);
1178 	if (error)
1179 		return (error);
1180 	error = vaccess(vp->v_type, vattr.va_mode, vattr.va_uid, vattr.va_gid,
1181 	    ap->a_accmode, ap->a_cred);
1182 	return (error);
1183 }
1184 
1185 #if 0
1186 struct vop_getattr_args {
1187 	struct vop_generic_args a_gen;
1188 	struct vnode *a_vp;
1189 	struct vattr *a_vap;
1190 	struct ucred *a_cred;
1191 };
1192 #endif
1193 
1194 /*
1195  * Get file attributes
1196  */
1197 static int
1198 mqfs_getattr(struct vop_getattr_args *ap)
1199 {
1200 	struct vnode *vp = ap->a_vp;
1201 	struct mqfs_node *pn = VTON(vp);
1202 	struct vattr *vap = ap->a_vap;
1203 	int error = 0;
1204 
1205 	vap->va_type = vp->v_type;
1206 	vap->va_mode = pn->mn_mode;
1207 	vap->va_nlink = 1;
1208 	vap->va_uid = pn->mn_uid;
1209 	vap->va_gid = pn->mn_gid;
1210 	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
1211 	vap->va_fileid = pn->mn_fileno;
1212 	vap->va_size = 0;
1213 	vap->va_blocksize = PAGE_SIZE;
1214 	vap->va_bytes = vap->va_size = 0;
1215 	vap->va_atime = pn->mn_atime;
1216 	vap->va_mtime = pn->mn_mtime;
1217 	vap->va_ctime = pn->mn_ctime;
1218 	vap->va_birthtime = pn->mn_birth;
1219 	vap->va_gen = 0;
1220 	vap->va_flags = 0;
1221 	vap->va_rdev = NODEV;
1222 	vap->va_bytes = 0;
1223 	vap->va_filerev = 0;
1224 	return (error);
1225 }
1226 
1227 #if 0
1228 struct vop_setattr_args {
1229 	struct vop_generic_args a_gen;
1230 	struct vnode *a_vp;
1231 	struct vattr *a_vap;
1232 	struct ucred *a_cred;
1233 };
1234 #endif
1235 /*
1236  * Set attributes
1237  */
1238 static int
1239 mqfs_setattr(struct vop_setattr_args *ap)
1240 {
1241 	struct mqfs_node *pn;
1242 	struct vattr *vap;
1243 	struct vnode *vp;
1244 	struct thread *td;
1245 	int c, error;
1246 	uid_t uid;
1247 	gid_t gid;
1248 
1249 	td = curthread;
1250 	vap = ap->a_vap;
1251 	vp = ap->a_vp;
1252 	if ((vap->va_type != VNON) ||
1253 	    (vap->va_nlink != VNOVAL) ||
1254 	    (vap->va_fsid != VNOVAL) ||
1255 	    (vap->va_fileid != VNOVAL) ||
1256 	    (vap->va_blocksize != VNOVAL) ||
1257 	    (vap->va_flags != VNOVAL && vap->va_flags != 0) ||
1258 	    (vap->va_rdev != VNOVAL) ||
1259 	    ((int)vap->va_bytes != VNOVAL) ||
1260 	    (vap->va_gen != VNOVAL)) {
1261 		return (EINVAL);
1262 	}
1263 
1264 	pn = VTON(vp);
1265 
1266 	error = c = 0;
1267 	if (vap->va_uid == (uid_t)VNOVAL)
1268 		uid = pn->mn_uid;
1269 	else
1270 		uid = vap->va_uid;
1271 	if (vap->va_gid == (gid_t)VNOVAL)
1272 		gid = pn->mn_gid;
1273 	else
1274 		gid = vap->va_gid;
1275 
1276 	if (uid != pn->mn_uid || gid != pn->mn_gid) {
1277 		/*
1278 		 * To modify the ownership of a file, must possess VADMIN
1279 		 * for that file.
1280 		 */
1281 		if ((error = VOP_ACCESS(vp, VADMIN, ap->a_cred, td)))
1282 			return (error);
1283 
1284 		/*
1285 		 * XXXRW: Why is there a privilege check here: shouldn't the
1286 		 * check in VOP_ACCESS() be enough?  Also, are the group bits
1287 		 * below definitely right?
1288 		 */
1289 		if (((ap->a_cred->cr_uid != pn->mn_uid) || uid != pn->mn_uid ||
1290 		    (gid != pn->mn_gid && !groupmember(gid, ap->a_cred))) &&
1291 		    (error = priv_check(td, PRIV_MQ_ADMIN)) != 0)
1292 			return (error);
1293 		pn->mn_uid = uid;
1294 		pn->mn_gid = gid;
1295 		c = 1;
1296 	}
1297 
1298 	if (vap->va_mode != (mode_t)VNOVAL) {
1299 		if ((ap->a_cred->cr_uid != pn->mn_uid) &&
1300 		    (error = priv_check(td, PRIV_MQ_ADMIN)))
1301 			return (error);
1302 		pn->mn_mode = vap->va_mode;
1303 		c = 1;
1304 	}
1305 
1306 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
1307 		/* See the comment in ufs_vnops::ufs_setattr(). */
1308 		if ((error = VOP_ACCESS(vp, VADMIN, ap->a_cred, td)) &&
1309 		    ((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
1310 		    (error = VOP_ACCESS(vp, VWRITE, ap->a_cred, td))))
1311 			return (error);
1312 		if (vap->va_atime.tv_sec != VNOVAL) {
1313 			pn->mn_atime = vap->va_atime;
1314 		}
1315 		if (vap->va_mtime.tv_sec != VNOVAL) {
1316 			pn->mn_mtime = vap->va_mtime;
1317 		}
1318 		c = 1;
1319 	}
1320 	if (c) {
1321 		vfs_timestamp(&pn->mn_ctime);
1322 	}
1323 	return (0);
1324 }
1325 
1326 #if 0
1327 struct vop_read_args {
1328 	struct vop_generic_args a_gen;
1329 	struct vnode *a_vp;
1330 	struct uio *a_uio;
1331 	int a_ioflag;
1332 	struct ucred *a_cred;
1333 };
1334 #endif
1335 
1336 /*
1337  * Read from a file
1338  */
1339 static int
1340 mqfs_read(struct vop_read_args *ap)
1341 {
1342 	char buf[80];
1343 	struct vnode *vp = ap->a_vp;
1344 	struct uio *uio = ap->a_uio;
1345 	struct mqueue *mq;
1346 	int len, error;
1347 
1348 	if (vp->v_type != VREG)
1349 		return (EINVAL);
1350 
1351 	mq = VTOMQ(vp);
1352 	snprintf(buf, sizeof(buf),
1353 		"QSIZE:%-10ld MAXMSG:%-10ld CURMSG:%-10ld MSGSIZE:%-10ld\n",
1354 		mq->mq_totalbytes,
1355 		mq->mq_maxmsg,
1356 		mq->mq_curmsgs,
1357 		mq->mq_msgsize);
1358 	buf[sizeof(buf)-1] = '\0';
1359 	len = strlen(buf);
1360 	error = uiomove_frombuf(buf, len, uio);
1361 	return (error);
1362 }
1363 
1364 #if 0
1365 struct vop_readdir_args {
1366 	struct vop_generic_args a_gen;
1367 	struct vnode *a_vp;
1368 	struct uio *a_uio;
1369 	struct ucred *a_cred;
1370 	int *a_eofflag;
1371 	int *a_ncookies;
1372 	u_long **a_cookies;
1373 };
1374 #endif
1375 
1376 /*
1377  * Return directory entries.
1378  */
1379 static int
1380 mqfs_readdir(struct vop_readdir_args *ap)
1381 {
1382 	struct vnode *vp;
1383 	struct mqfs_info *mi;
1384 	struct mqfs_node *pd;
1385 	struct mqfs_node *pn;
1386 	struct dirent entry;
1387 	struct uio *uio;
1388 	const void *pr_root;
1389 	int *tmp_ncookies = NULL;
1390 	off_t offset;
1391 	int error, i;
1392 
1393 	vp = ap->a_vp;
1394 	mi = VFSTOMQFS(vp->v_mount);
1395 	pd = VTON(vp);
1396 	uio = ap->a_uio;
1397 
1398 	if (vp->v_type != VDIR)
1399 		return (ENOTDIR);
1400 
1401 	if (uio->uio_offset < 0)
1402 		return (EINVAL);
1403 
1404 	if (ap->a_ncookies != NULL) {
1405 		tmp_ncookies = ap->a_ncookies;
1406 		*ap->a_ncookies = 0;
1407 		ap->a_ncookies = NULL;
1408         }
1409 
1410 	error = 0;
1411 	offset = 0;
1412 
1413 	pr_root = ap->a_cred->cr_prison->pr_root;
1414 	sx_xlock(&mi->mi_lock);
1415 
1416 	LIST_FOREACH(pn, &pd->mn_children, mn_sibling) {
1417 		entry.d_reclen = sizeof(entry);
1418 
1419 		/*
1420 		 * Only show names within the same prison root directory
1421 		 * (or not associated with a prison, e.g. "." and "..").
1422 		 */
1423 		if (pn->mn_pr_root != NULL && pn->mn_pr_root != pr_root)
1424 			continue;
1425 		if (!pn->mn_fileno)
1426 			mqfs_fileno_alloc(mi, pn);
1427 		entry.d_fileno = pn->mn_fileno;
1428 		for (i = 0; i < MQFS_NAMELEN - 1 && pn->mn_name[i] != '\0'; ++i)
1429 			entry.d_name[i] = pn->mn_name[i];
1430 		entry.d_namlen = i;
1431 		switch (pn->mn_type) {
1432 		case mqfstype_root:
1433 		case mqfstype_dir:
1434 		case mqfstype_this:
1435 		case mqfstype_parent:
1436 			entry.d_type = DT_DIR;
1437 			break;
1438 		case mqfstype_file:
1439 			entry.d_type = DT_REG;
1440 			break;
1441 		case mqfstype_symlink:
1442 			entry.d_type = DT_LNK;
1443 			break;
1444 		default:
1445 			panic("%s has unexpected node type: %d", pn->mn_name,
1446 				pn->mn_type);
1447 		}
1448 		dirent_terminate(&entry);
1449 		if (entry.d_reclen > uio->uio_resid)
1450                         break;
1451 		if (offset >= uio->uio_offset) {
1452 			error = vfs_read_dirent(ap, &entry, offset);
1453                         if (error)
1454                                 break;
1455                 }
1456                 offset += entry.d_reclen;
1457 	}
1458 	sx_xunlock(&mi->mi_lock);
1459 
1460 	uio->uio_offset = offset;
1461 
1462 	if (tmp_ncookies != NULL)
1463 		ap->a_ncookies = tmp_ncookies;
1464 
1465 	return (error);
1466 }
1467 
1468 #ifdef notyet
1469 
1470 #if 0
1471 struct vop_mkdir_args {
1472 	struct vnode *a_dvp;
1473 	struvt vnode **a_vpp;
1474 	struvt componentname *a_cnp;
1475 	struct vattr *a_vap;
1476 };
1477 #endif
1478 
1479 /*
1480  * Create a directory.
1481  */
1482 static int
1483 mqfs_mkdir(struct vop_mkdir_args *ap)
1484 {
1485 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount);
1486 	struct componentname *cnp = ap->a_cnp;
1487 	struct mqfs_node *pd = VTON(ap->a_dvp);
1488 	struct mqfs_node *pn;
1489 	int error;
1490 
1491 	if (pd->mn_type != mqfstype_root && pd->mn_type != mqfstype_dir)
1492 		return (ENOTDIR);
1493 	sx_xlock(&mqfs->mi_lock);
1494 	if ((cnp->cn_flags & HASBUF) == 0)
1495 		panic("%s: no name", __func__);
1496 	pn = mqfs_create_dir(pd, cnp->cn_nameptr, cnp->cn_namelen,
1497 		ap->a_vap->cn_cred, ap->a_vap->va_mode);
1498 	if (pn != NULL)
1499 		mqnode_addref(pn);
1500 	sx_xunlock(&mqfs->mi_lock);
1501 	if (pn == NULL) {
1502 		error = ENOSPC;
1503 	} else {
1504 		error = mqfs_allocv(ap->a_dvp->v_mount, ap->a_vpp, pn);
1505 		mqnode_release(pn);
1506 	}
1507 	return (error);
1508 }
1509 
1510 #if 0
1511 struct vop_rmdir_args {
1512 	struct vnode *a_dvp;
1513 	struct vnode *a_vp;
1514 	struct componentname *a_cnp;
1515 };
1516 #endif
1517 
1518 /*
1519  * Remove a directory.
1520  */
1521 static int
1522 mqfs_rmdir(struct vop_rmdir_args *ap)
1523 {
1524 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount);
1525 	struct mqfs_node *pn = VTON(ap->a_vp);
1526 	struct mqfs_node *pt;
1527 
1528 	if (pn->mn_type != mqfstype_dir)
1529 		return (ENOTDIR);
1530 
1531 	sx_xlock(&mqfs->mi_lock);
1532 	if (pn->mn_deleted) {
1533 		sx_xunlock(&mqfs->mi_lock);
1534 		return (ENOENT);
1535 	}
1536 
1537 	pt = LIST_FIRST(&pn->mn_children);
1538 	pt = LIST_NEXT(pt, mn_sibling);
1539 	pt = LIST_NEXT(pt, mn_sibling);
1540 	if (pt != NULL) {
1541 		sx_xunlock(&mqfs->mi_lock);
1542 		return (ENOTEMPTY);
1543 	}
1544 	pt = pn->mn_parent;
1545 	pn->mn_parent = NULL;
1546 	pn->mn_deleted = 1;
1547 	LIST_REMOVE(pn, mn_sibling);
1548 	mqnode_release(pn);
1549 	mqnode_release(pt);
1550 	sx_xunlock(&mqfs->mi_lock);
1551 	cache_purge(ap->a_vp);
1552 	return (0);
1553 }
1554 
1555 #endif /* notyet */
1556 
1557 /*
1558  * See if this prison root is obsolete, and clean up associated queues if it is.
1559  */
1560 static int
1561 mqfs_prison_remove(void *obj, void *data __unused)
1562 {
1563 	const struct prison *pr = obj;
1564 	const struct prison *tpr;
1565 	struct mqfs_node *pn, *tpn;
1566 	int found;
1567 
1568 	found = 0;
1569 	TAILQ_FOREACH(tpr, &allprison, pr_list) {
1570 		if (tpr->pr_root == pr->pr_root && tpr != pr && tpr->pr_ref > 0)
1571 			found = 1;
1572 	}
1573 	if (!found) {
1574 		/*
1575 		 * No jails are rooted in this directory anymore,
1576 		 * so no queues should be either.
1577 		 */
1578 		sx_xlock(&mqfs_data.mi_lock);
1579 		LIST_FOREACH_SAFE(pn, &mqfs_data.mi_root->mn_children,
1580 		    mn_sibling, tpn) {
1581 			if (pn->mn_pr_root == pr->pr_root)
1582 				(void)do_unlink(pn, curthread->td_ucred);
1583 		}
1584 		sx_xunlock(&mqfs_data.mi_lock);
1585 	}
1586 	return (0);
1587 }
1588 
1589 /*
1590  * Allocate a message queue
1591  */
1592 static struct mqueue *
1593 mqueue_alloc(const struct mq_attr *attr)
1594 {
1595 	struct mqueue *mq;
1596 
1597 	if (curmq >= maxmq)
1598 		return (NULL);
1599 	mq = uma_zalloc(mqueue_zone, M_WAITOK | M_ZERO);
1600 	TAILQ_INIT(&mq->mq_msgq);
1601 	if (attr != NULL) {
1602 		mq->mq_maxmsg = attr->mq_maxmsg;
1603 		mq->mq_msgsize = attr->mq_msgsize;
1604 	} else {
1605 		mq->mq_maxmsg = default_maxmsg;
1606 		mq->mq_msgsize = default_msgsize;
1607 	}
1608 	mtx_init(&mq->mq_mutex, "mqueue lock", NULL, MTX_DEF);
1609 	knlist_init_mtx(&mq->mq_rsel.si_note, &mq->mq_mutex);
1610 	knlist_init_mtx(&mq->mq_wsel.si_note, &mq->mq_mutex);
1611 	atomic_add_int(&curmq, 1);
1612 	return (mq);
1613 }
1614 
1615 /*
1616  * Destroy a message queue
1617  */
1618 static void
1619 mqueue_free(struct mqueue *mq)
1620 {
1621 	struct mqueue_msg *msg;
1622 
1623 	while ((msg = TAILQ_FIRST(&mq->mq_msgq)) != NULL) {
1624 		TAILQ_REMOVE(&mq->mq_msgq, msg, msg_link);
1625 		free(msg, M_MQUEUEDATA);
1626 	}
1627 
1628 	mtx_destroy(&mq->mq_mutex);
1629 	seldrain(&mq->mq_rsel);
1630 	seldrain(&mq->mq_wsel);
1631 	knlist_destroy(&mq->mq_rsel.si_note);
1632 	knlist_destroy(&mq->mq_wsel.si_note);
1633 	uma_zfree(mqueue_zone, mq);
1634 	atomic_add_int(&curmq, -1);
1635 }
1636 
1637 /*
1638  * Load a message from user space
1639  */
1640 static struct mqueue_msg *
1641 mqueue_loadmsg(const char *msg_ptr, size_t msg_size, int msg_prio)
1642 {
1643 	struct mqueue_msg *msg;
1644 	size_t len;
1645 	int error;
1646 
1647 	len = sizeof(struct mqueue_msg) + msg_size;
1648 	msg = malloc(len, M_MQUEUEDATA, M_WAITOK);
1649 	error = copyin(msg_ptr, ((char *)msg) + sizeof(struct mqueue_msg),
1650 	    msg_size);
1651 	if (error) {
1652 		free(msg, M_MQUEUEDATA);
1653 		msg = NULL;
1654 	} else {
1655 		msg->msg_size = msg_size;
1656 		msg->msg_prio = msg_prio;
1657 	}
1658 	return (msg);
1659 }
1660 
1661 /*
1662  * Save a message to user space
1663  */
1664 static int
1665 mqueue_savemsg(struct mqueue_msg *msg, char *msg_ptr, int *msg_prio)
1666 {
1667 	int error;
1668 
1669 	error = copyout(((char *)msg) + sizeof(*msg), msg_ptr,
1670 		msg->msg_size);
1671 	if (error == 0 && msg_prio != NULL)
1672 		error = copyout(&msg->msg_prio, msg_prio, sizeof(int));
1673 	return (error);
1674 }
1675 
1676 /*
1677  * Free a message's memory
1678  */
1679 static __inline void
1680 mqueue_freemsg(struct mqueue_msg *msg)
1681 {
1682 	free(msg, M_MQUEUEDATA);
1683 }
1684 
1685 /*
1686  * Send a message. if waitok is false, thread will not be
1687  * blocked if there is no data in queue, otherwise, absolute
1688  * time will be checked.
1689  */
1690 int
1691 mqueue_send(struct mqueue *mq, const char *msg_ptr,
1692 	size_t msg_len, unsigned msg_prio, int waitok,
1693 	const struct timespec *abs_timeout)
1694 {
1695 	struct mqueue_msg *msg;
1696 	struct timespec ts, ts2;
1697 	struct timeval tv;
1698 	int error;
1699 
1700 	if (msg_prio >= MQ_PRIO_MAX)
1701 		return (EINVAL);
1702 	if (msg_len > mq->mq_msgsize)
1703 		return (EMSGSIZE);
1704 	msg = mqueue_loadmsg(msg_ptr, msg_len, msg_prio);
1705 	if (msg == NULL)
1706 		return (EFAULT);
1707 
1708 	/* O_NONBLOCK case */
1709 	if (!waitok) {
1710 		error = _mqueue_send(mq, msg, -1);
1711 		if (error)
1712 			goto bad;
1713 		return (0);
1714 	}
1715 
1716 	/* we allow a null timeout (wait forever) */
1717 	if (abs_timeout == NULL) {
1718 		error = _mqueue_send(mq, msg, 0);
1719 		if (error)
1720 			goto bad;
1721 		return (0);
1722 	}
1723 
1724 	/* send it before checking time */
1725 	error = _mqueue_send(mq, msg, -1);
1726 	if (error == 0)
1727 		return (0);
1728 
1729 	if (error != EAGAIN)
1730 		goto bad;
1731 
1732 	if (abs_timeout->tv_nsec >= 1000000000 || abs_timeout->tv_nsec < 0) {
1733 		error = EINVAL;
1734 		goto bad;
1735 	}
1736 	for (;;) {
1737 		getnanotime(&ts);
1738 		timespecsub(abs_timeout, &ts, &ts2);
1739 		if (ts2.tv_sec < 0 || (ts2.tv_sec == 0 && ts2.tv_nsec <= 0)) {
1740 			error = ETIMEDOUT;
1741 			break;
1742 		}
1743 		TIMESPEC_TO_TIMEVAL(&tv, &ts2);
1744 		error = _mqueue_send(mq, msg, tvtohz(&tv));
1745 		if (error != ETIMEDOUT)
1746 			break;
1747 	}
1748 	if (error == 0)
1749 		return (0);
1750 bad:
1751 	mqueue_freemsg(msg);
1752 	return (error);
1753 }
1754 
1755 /*
1756  * Common routine to send a message
1757  */
1758 static int
1759 _mqueue_send(struct mqueue *mq, struct mqueue_msg *msg, int timo)
1760 {
1761 	struct mqueue_msg *msg2;
1762 	int error = 0;
1763 
1764 	mtx_lock(&mq->mq_mutex);
1765 	while (mq->mq_curmsgs >= mq->mq_maxmsg && error == 0) {
1766 		if (timo < 0) {
1767 			mtx_unlock(&mq->mq_mutex);
1768 			return (EAGAIN);
1769 		}
1770 		mq->mq_senders++;
1771 		error = msleep(&mq->mq_senders, &mq->mq_mutex,
1772 			    PCATCH, "mqsend", timo);
1773 		mq->mq_senders--;
1774 		if (error == EAGAIN)
1775 			error = ETIMEDOUT;
1776 	}
1777 	if (mq->mq_curmsgs >= mq->mq_maxmsg) {
1778 		mtx_unlock(&mq->mq_mutex);
1779 		return (error);
1780 	}
1781 	error = 0;
1782 	if (TAILQ_EMPTY(&mq->mq_msgq)) {
1783 		TAILQ_INSERT_HEAD(&mq->mq_msgq, msg, msg_link);
1784 	} else {
1785 		if (msg->msg_prio <= TAILQ_LAST(&mq->mq_msgq, msgq)->msg_prio) {
1786 			TAILQ_INSERT_TAIL(&mq->mq_msgq, msg, msg_link);
1787 		} else {
1788 			TAILQ_FOREACH(msg2, &mq->mq_msgq, msg_link) {
1789 				if (msg2->msg_prio < msg->msg_prio)
1790 					break;
1791 			}
1792 			TAILQ_INSERT_BEFORE(msg2, msg, msg_link);
1793 		}
1794 	}
1795 	mq->mq_curmsgs++;
1796 	mq->mq_totalbytes += msg->msg_size;
1797 	if (mq->mq_receivers)
1798 		wakeup_one(&mq->mq_receivers);
1799 	else if (mq->mq_notifier != NULL)
1800 		mqueue_send_notification(mq);
1801 	if (mq->mq_flags & MQ_RSEL) {
1802 		mq->mq_flags &= ~MQ_RSEL;
1803 		selwakeup(&mq->mq_rsel);
1804 	}
1805 	KNOTE_LOCKED(&mq->mq_rsel.si_note, 0);
1806 	mtx_unlock(&mq->mq_mutex);
1807 	return (0);
1808 }
1809 
1810 /*
1811  * Send realtime a signal to process which registered itself
1812  * successfully by mq_notify.
1813  */
1814 static void
1815 mqueue_send_notification(struct mqueue *mq)
1816 {
1817 	struct mqueue_notifier *nt;
1818 	struct thread *td;
1819 	struct proc *p;
1820 	int error;
1821 
1822 	mtx_assert(&mq->mq_mutex, MA_OWNED);
1823 	nt = mq->mq_notifier;
1824 	if (nt->nt_sigev.sigev_notify != SIGEV_NONE) {
1825 		p = nt->nt_proc;
1826 		error = sigev_findtd(p, &nt->nt_sigev, &td);
1827 		if (error) {
1828 			mq->mq_notifier = NULL;
1829 			return;
1830 		}
1831 		if (!KSI_ONQ(&nt->nt_ksi)) {
1832 			ksiginfo_set_sigev(&nt->nt_ksi, &nt->nt_sigev);
1833 			tdsendsignal(p, td, nt->nt_ksi.ksi_signo, &nt->nt_ksi);
1834 		}
1835 		PROC_UNLOCK(p);
1836 	}
1837 	mq->mq_notifier = NULL;
1838 }
1839 
1840 /*
1841  * Get a message. if waitok is false, thread will not be
1842  * blocked if there is no data in queue, otherwise, absolute
1843  * time will be checked.
1844  */
1845 int
1846 mqueue_receive(struct mqueue *mq, char *msg_ptr,
1847 	size_t msg_len, unsigned *msg_prio, int waitok,
1848 	const struct timespec *abs_timeout)
1849 {
1850 	struct mqueue_msg *msg;
1851 	struct timespec ts, ts2;
1852 	struct timeval tv;
1853 	int error;
1854 
1855 	if (msg_len < mq->mq_msgsize)
1856 		return (EMSGSIZE);
1857 
1858 	/* O_NONBLOCK case */
1859 	if (!waitok) {
1860 		error = _mqueue_recv(mq, &msg, -1);
1861 		if (error)
1862 			return (error);
1863 		goto received;
1864 	}
1865 
1866 	/* we allow a null timeout (wait forever). */
1867 	if (abs_timeout == NULL) {
1868 		error = _mqueue_recv(mq, &msg, 0);
1869 		if (error)
1870 			return (error);
1871 		goto received;
1872 	}
1873 
1874 	/* try to get a message before checking time */
1875 	error = _mqueue_recv(mq, &msg, -1);
1876 	if (error == 0)
1877 		goto received;
1878 
1879 	if (error != EAGAIN)
1880 		return (error);
1881 
1882 	if (abs_timeout->tv_nsec >= 1000000000 || abs_timeout->tv_nsec < 0) {
1883 		error = EINVAL;
1884 		return (error);
1885 	}
1886 
1887 	for (;;) {
1888 		getnanotime(&ts);
1889 		timespecsub(abs_timeout, &ts, &ts2);
1890 		if (ts2.tv_sec < 0 || (ts2.tv_sec == 0 && ts2.tv_nsec <= 0)) {
1891 			error = ETIMEDOUT;
1892 			return (error);
1893 		}
1894 		TIMESPEC_TO_TIMEVAL(&tv, &ts2);
1895 		error = _mqueue_recv(mq, &msg, tvtohz(&tv));
1896 		if (error == 0)
1897 			break;
1898 		if (error != ETIMEDOUT)
1899 			return (error);
1900 	}
1901 
1902 received:
1903 	error = mqueue_savemsg(msg, msg_ptr, msg_prio);
1904 	if (error == 0) {
1905 		curthread->td_retval[0] = msg->msg_size;
1906 		curthread->td_retval[1] = 0;
1907 	}
1908 	mqueue_freemsg(msg);
1909 	return (error);
1910 }
1911 
1912 /*
1913  * Common routine to receive a message
1914  */
1915 static int
1916 _mqueue_recv(struct mqueue *mq, struct mqueue_msg **msg, int timo)
1917 {
1918 	int error = 0;
1919 
1920 	mtx_lock(&mq->mq_mutex);
1921 	while ((*msg = TAILQ_FIRST(&mq->mq_msgq)) == NULL && error == 0) {
1922 		if (timo < 0) {
1923 			mtx_unlock(&mq->mq_mutex);
1924 			return (EAGAIN);
1925 		}
1926 		mq->mq_receivers++;
1927 		error = msleep(&mq->mq_receivers, &mq->mq_mutex,
1928 			    PCATCH, "mqrecv", timo);
1929 		mq->mq_receivers--;
1930 		if (error == EAGAIN)
1931 			error = ETIMEDOUT;
1932 	}
1933 	if (*msg != NULL) {
1934 		error = 0;
1935 		TAILQ_REMOVE(&mq->mq_msgq, *msg, msg_link);
1936 		mq->mq_curmsgs--;
1937 		mq->mq_totalbytes -= (*msg)->msg_size;
1938 		if (mq->mq_senders)
1939 			wakeup_one(&mq->mq_senders);
1940 		if (mq->mq_flags & MQ_WSEL) {
1941 			mq->mq_flags &= ~MQ_WSEL;
1942 			selwakeup(&mq->mq_wsel);
1943 		}
1944 		KNOTE_LOCKED(&mq->mq_wsel.si_note, 0);
1945 	}
1946 	if (mq->mq_notifier != NULL && mq->mq_receivers == 0 &&
1947 	    !TAILQ_EMPTY(&mq->mq_msgq)) {
1948 		mqueue_send_notification(mq);
1949 	}
1950 	mtx_unlock(&mq->mq_mutex);
1951 	return (error);
1952 }
1953 
1954 static __inline struct mqueue_notifier *
1955 notifier_alloc(void)
1956 {
1957 	return (uma_zalloc(mqnoti_zone, M_WAITOK | M_ZERO));
1958 }
1959 
1960 static __inline void
1961 notifier_free(struct mqueue_notifier *p)
1962 {
1963 	uma_zfree(mqnoti_zone, p);
1964 }
1965 
1966 static struct mqueue_notifier *
1967 notifier_search(struct proc *p, int fd)
1968 {
1969 	struct mqueue_notifier *nt;
1970 
1971 	LIST_FOREACH(nt, &p->p_mqnotifier, nt_link) {
1972 		if (nt->nt_ksi.ksi_mqd == fd)
1973 			break;
1974 	}
1975 	return (nt);
1976 }
1977 
1978 static __inline void
1979 notifier_insert(struct proc *p, struct mqueue_notifier *nt)
1980 {
1981 	LIST_INSERT_HEAD(&p->p_mqnotifier, nt, nt_link);
1982 }
1983 
1984 static __inline void
1985 notifier_delete(struct proc *p, struct mqueue_notifier *nt)
1986 {
1987 	LIST_REMOVE(nt, nt_link);
1988 	notifier_free(nt);
1989 }
1990 
1991 static void
1992 notifier_remove(struct proc *p, struct mqueue *mq, int fd)
1993 {
1994 	struct mqueue_notifier *nt;
1995 
1996 	mtx_assert(&mq->mq_mutex, MA_OWNED);
1997 	PROC_LOCK(p);
1998 	nt = notifier_search(p, fd);
1999 	if (nt != NULL) {
2000 		if (mq->mq_notifier == nt)
2001 			mq->mq_notifier = NULL;
2002 		sigqueue_take(&nt->nt_ksi);
2003 		notifier_delete(p, nt);
2004 	}
2005 	PROC_UNLOCK(p);
2006 }
2007 
2008 static int
2009 kern_kmq_open(struct thread *td, const char *upath, int flags, mode_t mode,
2010     const struct mq_attr *attr)
2011 {
2012 	char path[MQFS_NAMELEN + 1];
2013 	struct mqfs_node *pn;
2014 	struct filedesc *fdp;
2015 	struct file *fp;
2016 	struct mqueue *mq;
2017 	int fd, error, len, cmode;
2018 
2019 	AUDIT_ARG_FFLAGS(flags);
2020 	AUDIT_ARG_MODE(mode);
2021 
2022 	fdp = td->td_proc->p_fd;
2023 	cmode = (((mode & ~fdp->fd_cmask) & ALLPERMS) & ~S_ISTXT);
2024 	mq = NULL;
2025 	if ((flags & O_CREAT) != 0 && attr != NULL) {
2026 		if (attr->mq_maxmsg <= 0 || attr->mq_maxmsg > maxmsg)
2027 			return (EINVAL);
2028 		if (attr->mq_msgsize <= 0 || attr->mq_msgsize > maxmsgsize)
2029 			return (EINVAL);
2030 	}
2031 
2032 	error = copyinstr(upath, path, MQFS_NAMELEN + 1, NULL);
2033         if (error)
2034 		return (error);
2035 
2036 	/*
2037 	 * The first character of name must be a slash  (/) character
2038 	 * and the remaining characters of name cannot include any slash
2039 	 * characters.
2040 	 */
2041 	len = strlen(path);
2042 	if (len < 2 || path[0] != '/' || strchr(path + 1, '/') != NULL)
2043 		return (EINVAL);
2044 	/*
2045 	 * "." and ".." are magic directories, populated on the fly, and cannot
2046 	 * be opened as queues.
2047 	 */
2048 	if (strcmp(path, "/.") == 0 || strcmp(path, "/..") == 0)
2049 		return (EINVAL);
2050 	AUDIT_ARG_UPATH1_CANON(path);
2051 
2052 	error = falloc(td, &fp, &fd, O_CLOEXEC);
2053 	if (error)
2054 		return (error);
2055 
2056 	sx_xlock(&mqfs_data.mi_lock);
2057 	pn = mqfs_search(mqfs_data.mi_root, path + 1, len - 1, td->td_ucred);
2058 	if (pn == NULL) {
2059 		if (!(flags & O_CREAT)) {
2060 			error = ENOENT;
2061 		} else {
2062 			mq = mqueue_alloc(attr);
2063 			if (mq == NULL) {
2064 				error = ENFILE;
2065 			} else {
2066 				pn = mqfs_create_file(mqfs_data.mi_root,
2067 				         path + 1, len - 1, td->td_ucred,
2068 					 cmode);
2069 				if (pn == NULL) {
2070 					error = ENOSPC;
2071 					mqueue_free(mq);
2072 				}
2073 			}
2074 		}
2075 
2076 		if (error == 0) {
2077 			pn->mn_data = mq;
2078 		}
2079 	} else {
2080 		if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) {
2081 			error = EEXIST;
2082 		} else {
2083 			accmode_t accmode = 0;
2084 
2085 			if (flags & FREAD)
2086 				accmode |= VREAD;
2087 			if (flags & FWRITE)
2088 				accmode |= VWRITE;
2089 			error = vaccess(VREG, pn->mn_mode, pn->mn_uid,
2090 			    pn->mn_gid, accmode, td->td_ucred);
2091 		}
2092 	}
2093 
2094 	if (error) {
2095 		sx_xunlock(&mqfs_data.mi_lock);
2096 		fdclose(td, fp, fd);
2097 		fdrop(fp, td);
2098 		return (error);
2099 	}
2100 
2101 	mqnode_addref(pn);
2102 	sx_xunlock(&mqfs_data.mi_lock);
2103 
2104 	finit(fp, flags & (FREAD | FWRITE | O_NONBLOCK), DTYPE_MQUEUE, pn,
2105 	    &mqueueops);
2106 
2107 	td->td_retval[0] = fd;
2108 	fdrop(fp, td);
2109 	return (0);
2110 }
2111 
2112 /*
2113  * Syscall to open a message queue.
2114  */
2115 int
2116 sys_kmq_open(struct thread *td, struct kmq_open_args *uap)
2117 {
2118 	struct mq_attr attr;
2119 	int flags, error;
2120 
2121 	if ((uap->flags & O_ACCMODE) == O_ACCMODE || uap->flags & O_EXEC)
2122 		return (EINVAL);
2123 	flags = FFLAGS(uap->flags);
2124 	if ((flags & O_CREAT) != 0 && uap->attr != NULL) {
2125 		error = copyin(uap->attr, &attr, sizeof(attr));
2126 		if (error)
2127 			return (error);
2128 	}
2129 	return (kern_kmq_open(td, uap->path, flags, uap->mode,
2130 	    uap->attr != NULL ? &attr : NULL));
2131 }
2132 
2133 /*
2134  * Syscall to unlink a message queue.
2135  */
2136 int
2137 sys_kmq_unlink(struct thread *td, struct kmq_unlink_args *uap)
2138 {
2139 	char path[MQFS_NAMELEN+1];
2140 	struct mqfs_node *pn;
2141 	int error, len;
2142 
2143 	error = copyinstr(uap->path, path, MQFS_NAMELEN + 1, NULL);
2144         if (error)
2145 		return (error);
2146 
2147 	len = strlen(path);
2148 	if (len < 2 || path[0] != '/' || strchr(path + 1, '/') != NULL)
2149 		return (EINVAL);
2150 	if (strcmp(path, "/.") == 0 || strcmp(path, "/..") == 0)
2151 		return (EINVAL);
2152 	AUDIT_ARG_UPATH1_CANON(path);
2153 
2154 	sx_xlock(&mqfs_data.mi_lock);
2155 	pn = mqfs_search(mqfs_data.mi_root, path + 1, len - 1, td->td_ucred);
2156 	if (pn != NULL)
2157 		error = do_unlink(pn, td->td_ucred);
2158 	else
2159 		error = ENOENT;
2160 	sx_xunlock(&mqfs_data.mi_lock);
2161 	return (error);
2162 }
2163 
2164 typedef int (*_fgetf)(struct thread *, int, cap_rights_t *, struct file **);
2165 
2166 /*
2167  * Get message queue by giving file slot
2168  */
2169 static int
2170 _getmq(struct thread *td, int fd, cap_rights_t *rightsp, _fgetf func,
2171        struct file **fpp, struct mqfs_node **ppn, struct mqueue **pmq)
2172 {
2173 	struct mqfs_node *pn;
2174 	int error;
2175 
2176 	error = func(td, fd, rightsp, fpp);
2177 	if (error)
2178 		return (error);
2179 	if (&mqueueops != (*fpp)->f_ops) {
2180 		fdrop(*fpp, td);
2181 		return (EBADF);
2182 	}
2183 	pn = (*fpp)->f_data;
2184 	if (ppn)
2185 		*ppn = pn;
2186 	if (pmq)
2187 		*pmq = pn->mn_data;
2188 	return (0);
2189 }
2190 
2191 static __inline int
2192 getmq(struct thread *td, int fd, struct file **fpp, struct mqfs_node **ppn,
2193 	struct mqueue **pmq)
2194 {
2195 
2196 	return _getmq(td, fd, &cap_event_rights, fget,
2197 	    fpp, ppn, pmq);
2198 }
2199 
2200 static __inline int
2201 getmq_read(struct thread *td, int fd, struct file **fpp,
2202 	 struct mqfs_node **ppn, struct mqueue **pmq)
2203 {
2204 
2205 	return _getmq(td, fd, &cap_read_rights, fget_read,
2206 	    fpp, ppn, pmq);
2207 }
2208 
2209 static __inline int
2210 getmq_write(struct thread *td, int fd, struct file **fpp,
2211 	struct mqfs_node **ppn, struct mqueue **pmq)
2212 {
2213 
2214 	return _getmq(td, fd, &cap_write_rights, fget_write,
2215 	    fpp, ppn, pmq);
2216 }
2217 
2218 static int
2219 kern_kmq_setattr(struct thread *td, int mqd, const struct mq_attr *attr,
2220     struct mq_attr *oattr)
2221 {
2222 	struct mqueue *mq;
2223 	struct file *fp;
2224 	u_int oflag, flag;
2225 	int error;
2226 
2227 	AUDIT_ARG_FD(mqd);
2228 	if (attr != NULL && (attr->mq_flags & ~O_NONBLOCK) != 0)
2229 		return (EINVAL);
2230 	error = getmq(td, mqd, &fp, NULL, &mq);
2231 	if (error)
2232 		return (error);
2233 	oattr->mq_maxmsg  = mq->mq_maxmsg;
2234 	oattr->mq_msgsize = mq->mq_msgsize;
2235 	oattr->mq_curmsgs = mq->mq_curmsgs;
2236 	if (attr != NULL) {
2237 		do {
2238 			oflag = flag = fp->f_flag;
2239 			flag &= ~O_NONBLOCK;
2240 			flag |= (attr->mq_flags & O_NONBLOCK);
2241 		} while (atomic_cmpset_int(&fp->f_flag, oflag, flag) == 0);
2242 	} else
2243 		oflag = fp->f_flag;
2244 	oattr->mq_flags = (O_NONBLOCK & oflag);
2245 	fdrop(fp, td);
2246 	return (error);
2247 }
2248 
2249 int
2250 sys_kmq_setattr(struct thread *td, struct kmq_setattr_args *uap)
2251 {
2252 	struct mq_attr attr, oattr;
2253 	int error;
2254 
2255 	if (uap->attr != NULL) {
2256 		error = copyin(uap->attr, &attr, sizeof(attr));
2257 		if (error != 0)
2258 			return (error);
2259 	}
2260 	error = kern_kmq_setattr(td, uap->mqd, uap->attr != NULL ? &attr : NULL,
2261 	    &oattr);
2262 	if (error == 0 && uap->oattr != NULL) {
2263 		bzero(oattr.__reserved, sizeof(oattr.__reserved));
2264 		error = copyout(&oattr, uap->oattr, sizeof(oattr));
2265 	}
2266 	return (error);
2267 }
2268 
2269 int
2270 sys_kmq_timedreceive(struct thread *td, struct kmq_timedreceive_args *uap)
2271 {
2272 	struct mqueue *mq;
2273 	struct file *fp;
2274 	struct timespec *abs_timeout, ets;
2275 	int error;
2276 	int waitok;
2277 
2278 	AUDIT_ARG_FD(uap->mqd);
2279 	error = getmq_read(td, uap->mqd, &fp, NULL, &mq);
2280 	if (error)
2281 		return (error);
2282 	if (uap->abs_timeout != NULL) {
2283 		error = copyin(uap->abs_timeout, &ets, sizeof(ets));
2284 		if (error != 0)
2285 			goto out;
2286 		abs_timeout = &ets;
2287 	} else
2288 		abs_timeout = NULL;
2289 	waitok = !(fp->f_flag & O_NONBLOCK);
2290 	error = mqueue_receive(mq, uap->msg_ptr, uap->msg_len,
2291 		uap->msg_prio, waitok, abs_timeout);
2292 out:
2293 	fdrop(fp, td);
2294 	return (error);
2295 }
2296 
2297 int
2298 sys_kmq_timedsend(struct thread *td, struct kmq_timedsend_args *uap)
2299 {
2300 	struct mqueue *mq;
2301 	struct file *fp;
2302 	struct timespec *abs_timeout, ets;
2303 	int error, waitok;
2304 
2305 	AUDIT_ARG_FD(uap->mqd);
2306 	error = getmq_write(td, uap->mqd, &fp, NULL, &mq);
2307 	if (error)
2308 		return (error);
2309 	if (uap->abs_timeout != NULL) {
2310 		error = copyin(uap->abs_timeout, &ets, sizeof(ets));
2311 		if (error != 0)
2312 			goto out;
2313 		abs_timeout = &ets;
2314 	} else
2315 		abs_timeout = NULL;
2316 	waitok = !(fp->f_flag & O_NONBLOCK);
2317 	error = mqueue_send(mq, uap->msg_ptr, uap->msg_len,
2318 		uap->msg_prio, waitok, abs_timeout);
2319 out:
2320 	fdrop(fp, td);
2321 	return (error);
2322 }
2323 
2324 static int
2325 kern_kmq_notify(struct thread *td, int mqd, struct sigevent *sigev)
2326 {
2327 	struct filedesc *fdp;
2328 	struct proc *p;
2329 	struct mqueue *mq;
2330 	struct file *fp, *fp2;
2331 	struct mqueue_notifier *nt, *newnt = NULL;
2332 	int error;
2333 
2334 	AUDIT_ARG_FD(mqd);
2335 	if (sigev != NULL) {
2336 		if (sigev->sigev_notify != SIGEV_SIGNAL &&
2337 		    sigev->sigev_notify != SIGEV_THREAD_ID &&
2338 		    sigev->sigev_notify != SIGEV_NONE)
2339 			return (EINVAL);
2340 		if ((sigev->sigev_notify == SIGEV_SIGNAL ||
2341 		    sigev->sigev_notify == SIGEV_THREAD_ID) &&
2342 		    !_SIG_VALID(sigev->sigev_signo))
2343 			return (EINVAL);
2344 	}
2345 	p = td->td_proc;
2346 	fdp = td->td_proc->p_fd;
2347 	error = getmq(td, mqd, &fp, NULL, &mq);
2348 	if (error)
2349 		return (error);
2350 again:
2351 	FILEDESC_SLOCK(fdp);
2352 	fp2 = fget_locked(fdp, mqd);
2353 	if (fp2 == NULL) {
2354 		FILEDESC_SUNLOCK(fdp);
2355 		error = EBADF;
2356 		goto out;
2357 	}
2358 #ifdef CAPABILITIES
2359 	error = cap_check(cap_rights(fdp, mqd), &cap_event_rights);
2360 	if (error) {
2361 		FILEDESC_SUNLOCK(fdp);
2362 		goto out;
2363 	}
2364 #endif
2365 	if (fp2 != fp) {
2366 		FILEDESC_SUNLOCK(fdp);
2367 		error = EBADF;
2368 		goto out;
2369 	}
2370 	mtx_lock(&mq->mq_mutex);
2371 	FILEDESC_SUNLOCK(fdp);
2372 	if (sigev != NULL) {
2373 		if (mq->mq_notifier != NULL) {
2374 			error = EBUSY;
2375 		} else {
2376 			PROC_LOCK(p);
2377 			nt = notifier_search(p, mqd);
2378 			if (nt == NULL) {
2379 				if (newnt == NULL) {
2380 					PROC_UNLOCK(p);
2381 					mtx_unlock(&mq->mq_mutex);
2382 					newnt = notifier_alloc();
2383 					goto again;
2384 				}
2385 			}
2386 
2387 			if (nt != NULL) {
2388 				sigqueue_take(&nt->nt_ksi);
2389 				if (newnt != NULL) {
2390 					notifier_free(newnt);
2391 					newnt = NULL;
2392 				}
2393 			} else {
2394 				nt = newnt;
2395 				newnt = NULL;
2396 				ksiginfo_init(&nt->nt_ksi);
2397 				nt->nt_ksi.ksi_flags |= KSI_INS | KSI_EXT;
2398 				nt->nt_ksi.ksi_code = SI_MESGQ;
2399 				nt->nt_proc = p;
2400 				nt->nt_ksi.ksi_mqd = mqd;
2401 				notifier_insert(p, nt);
2402 			}
2403 			nt->nt_sigev = *sigev;
2404 			mq->mq_notifier = nt;
2405 			PROC_UNLOCK(p);
2406 			/*
2407 			 * if there is no receivers and message queue
2408 			 * is not empty, we should send notification
2409 			 * as soon as possible.
2410 			 */
2411 			if (mq->mq_receivers == 0 &&
2412 			    !TAILQ_EMPTY(&mq->mq_msgq))
2413 				mqueue_send_notification(mq);
2414 		}
2415 	} else {
2416 		notifier_remove(p, mq, mqd);
2417 	}
2418 	mtx_unlock(&mq->mq_mutex);
2419 
2420 out:
2421 	fdrop(fp, td);
2422 	if (newnt != NULL)
2423 		notifier_free(newnt);
2424 	return (error);
2425 }
2426 
2427 int
2428 sys_kmq_notify(struct thread *td, struct kmq_notify_args *uap)
2429 {
2430 	struct sigevent ev, *evp;
2431 	int error;
2432 
2433 	if (uap->sigev == NULL) {
2434 		evp = NULL;
2435 	} else {
2436 		error = copyin(uap->sigev, &ev, sizeof(ev));
2437 		if (error != 0)
2438 			return (error);
2439 		evp = &ev;
2440 	}
2441 	return (kern_kmq_notify(td, uap->mqd, evp));
2442 }
2443 
2444 static void
2445 mqueue_fdclose(struct thread *td, int fd, struct file *fp)
2446 {
2447 	struct mqueue *mq;
2448 #ifdef INVARIANTS
2449 	struct filedesc *fdp;
2450 
2451 	fdp = td->td_proc->p_fd;
2452 	FILEDESC_LOCK_ASSERT(fdp);
2453 #endif
2454 
2455 	if (fp->f_ops == &mqueueops) {
2456 		mq = FPTOMQ(fp);
2457 		mtx_lock(&mq->mq_mutex);
2458 		notifier_remove(td->td_proc, mq, fd);
2459 
2460 		/* have to wakeup thread in same process */
2461 		if (mq->mq_flags & MQ_RSEL) {
2462 			mq->mq_flags &= ~MQ_RSEL;
2463 			selwakeup(&mq->mq_rsel);
2464 		}
2465 		if (mq->mq_flags & MQ_WSEL) {
2466 			mq->mq_flags &= ~MQ_WSEL;
2467 			selwakeup(&mq->mq_wsel);
2468 		}
2469 		mtx_unlock(&mq->mq_mutex);
2470 	}
2471 }
2472 
2473 static void
2474 mq_proc_exit(void *arg __unused, struct proc *p)
2475 {
2476 	struct filedesc *fdp;
2477 	struct file *fp;
2478 	struct mqueue *mq;
2479 	int i;
2480 
2481 	fdp = p->p_fd;
2482 	FILEDESC_SLOCK(fdp);
2483 	for (i = 0; i < fdp->fd_nfiles; ++i) {
2484 		fp = fget_locked(fdp, i);
2485 		if (fp != NULL && fp->f_ops == &mqueueops) {
2486 			mq = FPTOMQ(fp);
2487 			mtx_lock(&mq->mq_mutex);
2488 			notifier_remove(p, FPTOMQ(fp), i);
2489 			mtx_unlock(&mq->mq_mutex);
2490 		}
2491 	}
2492 	FILEDESC_SUNLOCK(fdp);
2493 	KASSERT(LIST_EMPTY(&p->p_mqnotifier), ("mq notifiers left"));
2494 }
2495 
2496 static int
2497 mqf_poll(struct file *fp, int events, struct ucred *active_cred,
2498 	struct thread *td)
2499 {
2500 	struct mqueue *mq = FPTOMQ(fp);
2501 	int revents = 0;
2502 
2503 	mtx_lock(&mq->mq_mutex);
2504 	if (events & (POLLIN | POLLRDNORM)) {
2505 		if (mq->mq_curmsgs) {
2506 			revents |= events & (POLLIN | POLLRDNORM);
2507 		} else {
2508 			mq->mq_flags |= MQ_RSEL;
2509 			selrecord(td, &mq->mq_rsel);
2510  		}
2511 	}
2512 	if (events & POLLOUT) {
2513 		if (mq->mq_curmsgs < mq->mq_maxmsg)
2514 			revents |= POLLOUT;
2515 		else {
2516 			mq->mq_flags |= MQ_WSEL;
2517 			selrecord(td, &mq->mq_wsel);
2518 		}
2519 	}
2520 	mtx_unlock(&mq->mq_mutex);
2521 	return (revents);
2522 }
2523 
2524 static int
2525 mqf_close(struct file *fp, struct thread *td)
2526 {
2527 	struct mqfs_node *pn;
2528 
2529 	fp->f_ops = &badfileops;
2530 	pn = fp->f_data;
2531 	fp->f_data = NULL;
2532 	sx_xlock(&mqfs_data.mi_lock);
2533 	mqnode_release(pn);
2534 	sx_xunlock(&mqfs_data.mi_lock);
2535 	return (0);
2536 }
2537 
2538 static int
2539 mqf_stat(struct file *fp, struct stat *st, struct ucred *active_cred,
2540 	struct thread *td)
2541 {
2542 	struct mqfs_node *pn = fp->f_data;
2543 
2544 	bzero(st, sizeof *st);
2545 	sx_xlock(&mqfs_data.mi_lock);
2546 	st->st_atim = pn->mn_atime;
2547 	st->st_mtim = pn->mn_mtime;
2548 	st->st_ctim = pn->mn_ctime;
2549 	st->st_birthtim = pn->mn_birth;
2550 	st->st_uid = pn->mn_uid;
2551 	st->st_gid = pn->mn_gid;
2552 	st->st_mode = S_IFIFO | pn->mn_mode;
2553 	sx_xunlock(&mqfs_data.mi_lock);
2554 	return (0);
2555 }
2556 
2557 static int
2558 mqf_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
2559     struct thread *td)
2560 {
2561 	struct mqfs_node *pn;
2562 	int error;
2563 
2564 	error = 0;
2565 	pn = fp->f_data;
2566 	sx_xlock(&mqfs_data.mi_lock);
2567 	error = vaccess(VREG, pn->mn_mode, pn->mn_uid, pn->mn_gid, VADMIN,
2568 	    active_cred);
2569 	if (error != 0)
2570 		goto out;
2571 	pn->mn_mode = mode & ACCESSPERMS;
2572 out:
2573 	sx_xunlock(&mqfs_data.mi_lock);
2574 	return (error);
2575 }
2576 
2577 static int
2578 mqf_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
2579     struct thread *td)
2580 {
2581 	struct mqfs_node *pn;
2582 	int error;
2583 
2584 	error = 0;
2585 	pn = fp->f_data;
2586 	sx_xlock(&mqfs_data.mi_lock);
2587 	if (uid == (uid_t)-1)
2588 		uid = pn->mn_uid;
2589 	if (gid == (gid_t)-1)
2590 		gid = pn->mn_gid;
2591 	if (((uid != pn->mn_uid && uid != active_cred->cr_uid) ||
2592 	    (gid != pn->mn_gid && !groupmember(gid, active_cred))) &&
2593 	    (error = priv_check_cred(active_cred, PRIV_VFS_CHOWN)))
2594 		goto out;
2595 	pn->mn_uid = uid;
2596 	pn->mn_gid = gid;
2597 out:
2598 	sx_xunlock(&mqfs_data.mi_lock);
2599 	return (error);
2600 }
2601 
2602 static int
2603 mqf_kqfilter(struct file *fp, struct knote *kn)
2604 {
2605 	struct mqueue *mq = FPTOMQ(fp);
2606 	int error = 0;
2607 
2608 	if (kn->kn_filter == EVFILT_READ) {
2609 		kn->kn_fop = &mq_rfiltops;
2610 		knlist_add(&mq->mq_rsel.si_note, kn, 0);
2611 	} else if (kn->kn_filter == EVFILT_WRITE) {
2612 		kn->kn_fop = &mq_wfiltops;
2613 		knlist_add(&mq->mq_wsel.si_note, kn, 0);
2614 	} else
2615 		error = EINVAL;
2616 	return (error);
2617 }
2618 
2619 static void
2620 filt_mqdetach(struct knote *kn)
2621 {
2622 	struct mqueue *mq = FPTOMQ(kn->kn_fp);
2623 
2624 	if (kn->kn_filter == EVFILT_READ)
2625 		knlist_remove(&mq->mq_rsel.si_note, kn, 0);
2626 	else if (kn->kn_filter == EVFILT_WRITE)
2627 		knlist_remove(&mq->mq_wsel.si_note, kn, 0);
2628 	else
2629 		panic("filt_mqdetach");
2630 }
2631 
2632 static int
2633 filt_mqread(struct knote *kn, long hint)
2634 {
2635 	struct mqueue *mq = FPTOMQ(kn->kn_fp);
2636 
2637 	mtx_assert(&mq->mq_mutex, MA_OWNED);
2638 	return (mq->mq_curmsgs != 0);
2639 }
2640 
2641 static int
2642 filt_mqwrite(struct knote *kn, long hint)
2643 {
2644 	struct mqueue *mq = FPTOMQ(kn->kn_fp);
2645 
2646 	mtx_assert(&mq->mq_mutex, MA_OWNED);
2647 	return (mq->mq_curmsgs < mq->mq_maxmsg);
2648 }
2649 
2650 static int
2651 mqf_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
2652 {
2653 
2654 	kif->kf_type = KF_TYPE_MQUEUE;
2655 	return (0);
2656 }
2657 
2658 static struct fileops mqueueops = {
2659 	.fo_read		= invfo_rdwr,
2660 	.fo_write		= invfo_rdwr,
2661 	.fo_truncate		= invfo_truncate,
2662 	.fo_ioctl		= invfo_ioctl,
2663 	.fo_poll		= mqf_poll,
2664 	.fo_kqfilter		= mqf_kqfilter,
2665 	.fo_stat		= mqf_stat,
2666 	.fo_close		= mqf_close,
2667 	.fo_chmod		= mqf_chmod,
2668 	.fo_chown		= mqf_chown,
2669 	.fo_sendfile		= invfo_sendfile,
2670 	.fo_fill_kinfo		= mqf_fill_kinfo,
2671 	.fo_flags		= DFLAG_PASSABLE,
2672 };
2673 
2674 static struct vop_vector mqfs_vnodeops = {
2675 	.vop_default 		= &default_vnodeops,
2676 	.vop_access		= mqfs_access,
2677 	.vop_cachedlookup	= mqfs_lookup,
2678 	.vop_lookup		= vfs_cache_lookup,
2679 	.vop_reclaim		= mqfs_reclaim,
2680 	.vop_create		= mqfs_create,
2681 	.vop_remove		= mqfs_remove,
2682 	.vop_inactive		= mqfs_inactive,
2683 	.vop_open		= mqfs_open,
2684 	.vop_close		= mqfs_close,
2685 	.vop_getattr		= mqfs_getattr,
2686 	.vop_setattr		= mqfs_setattr,
2687 	.vop_read		= mqfs_read,
2688 	.vop_write		= VOP_EOPNOTSUPP,
2689 	.vop_readdir		= mqfs_readdir,
2690 	.vop_mkdir		= VOP_EOPNOTSUPP,
2691 	.vop_rmdir		= VOP_EOPNOTSUPP
2692 };
2693 VFS_VOP_VECTOR_REGISTER(mqfs_vnodeops);
2694 
2695 static struct vfsops mqfs_vfsops = {
2696 	.vfs_init 		= mqfs_init,
2697 	.vfs_uninit		= mqfs_uninit,
2698 	.vfs_mount		= mqfs_mount,
2699 	.vfs_unmount		= mqfs_unmount,
2700 	.vfs_root		= mqfs_root,
2701 	.vfs_statfs		= mqfs_statfs,
2702 };
2703 
2704 static struct vfsconf mqueuefs_vfsconf = {
2705 	.vfc_version = VFS_VERSION,
2706 	.vfc_name = "mqueuefs",
2707 	.vfc_vfsops = &mqfs_vfsops,
2708 	.vfc_typenum = -1,
2709 	.vfc_flags = VFCF_SYNTHETIC
2710 };
2711 
2712 static struct syscall_helper_data mq_syscalls[] = {
2713 	SYSCALL_INIT_HELPER(kmq_open),
2714 	SYSCALL_INIT_HELPER_F(kmq_setattr, SYF_CAPENABLED),
2715 	SYSCALL_INIT_HELPER_F(kmq_timedsend, SYF_CAPENABLED),
2716 	SYSCALL_INIT_HELPER_F(kmq_timedreceive, SYF_CAPENABLED),
2717 	SYSCALL_INIT_HELPER_F(kmq_notify, SYF_CAPENABLED),
2718 	SYSCALL_INIT_HELPER(kmq_unlink),
2719 	SYSCALL_INIT_LAST
2720 };
2721 
2722 #ifdef COMPAT_FREEBSD32
2723 #include <compat/freebsd32/freebsd32.h>
2724 #include <compat/freebsd32/freebsd32_proto.h>
2725 #include <compat/freebsd32/freebsd32_signal.h>
2726 #include <compat/freebsd32/freebsd32_syscall.h>
2727 #include <compat/freebsd32/freebsd32_util.h>
2728 
2729 static void
2730 mq_attr_from32(const struct mq_attr32 *from, struct mq_attr *to)
2731 {
2732 
2733 	to->mq_flags = from->mq_flags;
2734 	to->mq_maxmsg = from->mq_maxmsg;
2735 	to->mq_msgsize = from->mq_msgsize;
2736 	to->mq_curmsgs = from->mq_curmsgs;
2737 }
2738 
2739 static void
2740 mq_attr_to32(const struct mq_attr *from, struct mq_attr32 *to)
2741 {
2742 
2743 	to->mq_flags = from->mq_flags;
2744 	to->mq_maxmsg = from->mq_maxmsg;
2745 	to->mq_msgsize = from->mq_msgsize;
2746 	to->mq_curmsgs = from->mq_curmsgs;
2747 }
2748 
2749 int
2750 freebsd32_kmq_open(struct thread *td, struct freebsd32_kmq_open_args *uap)
2751 {
2752 	struct mq_attr attr;
2753 	struct mq_attr32 attr32;
2754 	int flags, error;
2755 
2756 	if ((uap->flags & O_ACCMODE) == O_ACCMODE || uap->flags & O_EXEC)
2757 		return (EINVAL);
2758 	flags = FFLAGS(uap->flags);
2759 	if ((flags & O_CREAT) != 0 && uap->attr != NULL) {
2760 		error = copyin(uap->attr, &attr32, sizeof(attr32));
2761 		if (error)
2762 			return (error);
2763 		mq_attr_from32(&attr32, &attr);
2764 	}
2765 	return (kern_kmq_open(td, uap->path, flags, uap->mode,
2766 	    uap->attr != NULL ? &attr : NULL));
2767 }
2768 
2769 int
2770 freebsd32_kmq_setattr(struct thread *td, struct freebsd32_kmq_setattr_args *uap)
2771 {
2772 	struct mq_attr attr, oattr;
2773 	struct mq_attr32 attr32, oattr32;
2774 	int error;
2775 
2776 	if (uap->attr != NULL) {
2777 		error = copyin(uap->attr, &attr32, sizeof(attr32));
2778 		if (error != 0)
2779 			return (error);
2780 		mq_attr_from32(&attr32, &attr);
2781 	}
2782 	error = kern_kmq_setattr(td, uap->mqd, uap->attr != NULL ? &attr : NULL,
2783 	    &oattr);
2784 	if (error == 0 && uap->oattr != NULL) {
2785 		mq_attr_to32(&oattr, &oattr32);
2786 		bzero(oattr32.__reserved, sizeof(oattr32.__reserved));
2787 		error = copyout(&oattr32, uap->oattr, sizeof(oattr32));
2788 	}
2789 	return (error);
2790 }
2791 
2792 int
2793 freebsd32_kmq_timedsend(struct thread *td,
2794     struct freebsd32_kmq_timedsend_args *uap)
2795 {
2796 	struct mqueue *mq;
2797 	struct file *fp;
2798 	struct timespec32 ets32;
2799 	struct timespec *abs_timeout, ets;
2800 	int error;
2801 	int waitok;
2802 
2803 	AUDIT_ARG_FD(uap->mqd);
2804 	error = getmq_write(td, uap->mqd, &fp, NULL, &mq);
2805 	if (error)
2806 		return (error);
2807 	if (uap->abs_timeout != NULL) {
2808 		error = copyin(uap->abs_timeout, &ets32, sizeof(ets32));
2809 		if (error != 0)
2810 			goto out;
2811 		CP(ets32, ets, tv_sec);
2812 		CP(ets32, ets, tv_nsec);
2813 		abs_timeout = &ets;
2814 	} else
2815 		abs_timeout = NULL;
2816 	waitok = !(fp->f_flag & O_NONBLOCK);
2817 	error = mqueue_send(mq, uap->msg_ptr, uap->msg_len,
2818 		uap->msg_prio, waitok, abs_timeout);
2819 out:
2820 	fdrop(fp, td);
2821 	return (error);
2822 }
2823 
2824 int
2825 freebsd32_kmq_timedreceive(struct thread *td,
2826     struct freebsd32_kmq_timedreceive_args *uap)
2827 {
2828 	struct mqueue *mq;
2829 	struct file *fp;
2830 	struct timespec32 ets32;
2831 	struct timespec *abs_timeout, ets;
2832 	int error, waitok;
2833 
2834 	AUDIT_ARG_FD(uap->mqd);
2835 	error = getmq_read(td, uap->mqd, &fp, NULL, &mq);
2836 	if (error)
2837 		return (error);
2838 	if (uap->abs_timeout != NULL) {
2839 		error = copyin(uap->abs_timeout, &ets32, sizeof(ets32));
2840 		if (error != 0)
2841 			goto out;
2842 		CP(ets32, ets, tv_sec);
2843 		CP(ets32, ets, tv_nsec);
2844 		abs_timeout = &ets;
2845 	} else
2846 		abs_timeout = NULL;
2847 	waitok = !(fp->f_flag & O_NONBLOCK);
2848 	error = mqueue_receive(mq, uap->msg_ptr, uap->msg_len,
2849 		uap->msg_prio, waitok, abs_timeout);
2850 out:
2851 	fdrop(fp, td);
2852 	return (error);
2853 }
2854 
2855 int
2856 freebsd32_kmq_notify(struct thread *td, struct freebsd32_kmq_notify_args *uap)
2857 {
2858 	struct sigevent ev, *evp;
2859 	struct sigevent32 ev32;
2860 	int error;
2861 
2862 	if (uap->sigev == NULL) {
2863 		evp = NULL;
2864 	} else {
2865 		error = copyin(uap->sigev, &ev32, sizeof(ev32));
2866 		if (error != 0)
2867 			return (error);
2868 		error = convert_sigevent32(&ev32, &ev);
2869 		if (error != 0)
2870 			return (error);
2871 		evp = &ev;
2872 	}
2873 	return (kern_kmq_notify(td, uap->mqd, evp));
2874 }
2875 
2876 static struct syscall_helper_data mq32_syscalls[] = {
2877 	SYSCALL32_INIT_HELPER(freebsd32_kmq_open),
2878 	SYSCALL32_INIT_HELPER_F(freebsd32_kmq_setattr, SYF_CAPENABLED),
2879 	SYSCALL32_INIT_HELPER_F(freebsd32_kmq_timedsend, SYF_CAPENABLED),
2880 	SYSCALL32_INIT_HELPER_F(freebsd32_kmq_timedreceive, SYF_CAPENABLED),
2881 	SYSCALL32_INIT_HELPER_F(freebsd32_kmq_notify, SYF_CAPENABLED),
2882 	SYSCALL32_INIT_HELPER_COMPAT(kmq_unlink),
2883 	SYSCALL_INIT_LAST
2884 };
2885 #endif
2886 
2887 static int
2888 mqinit(void)
2889 {
2890 	int error;
2891 
2892 	error = syscall_helper_register(mq_syscalls, SY_THR_STATIC_KLD);
2893 	if (error != 0)
2894 		return (error);
2895 #ifdef COMPAT_FREEBSD32
2896 	error = syscall32_helper_register(mq32_syscalls, SY_THR_STATIC_KLD);
2897 	if (error != 0)
2898 		return (error);
2899 #endif
2900 	return (0);
2901 }
2902 
2903 static int
2904 mqunload(void)
2905 {
2906 
2907 #ifdef COMPAT_FREEBSD32
2908 	syscall32_helper_unregister(mq32_syscalls);
2909 #endif
2910 	syscall_helper_unregister(mq_syscalls);
2911 	return (0);
2912 }
2913 
2914 static int
2915 mq_modload(struct module *module, int cmd, void *arg)
2916 {
2917 	int error = 0;
2918 
2919 	error = vfs_modevent(module, cmd, arg);
2920 	if (error != 0)
2921 		return (error);
2922 
2923 	switch (cmd) {
2924 	case MOD_LOAD:
2925 		error = mqinit();
2926 		if (error != 0)
2927 			mqunload();
2928 		break;
2929 	case MOD_UNLOAD:
2930 		error = mqunload();
2931 		break;
2932 	default:
2933 		break;
2934 	}
2935 	return (error);
2936 }
2937 
2938 static moduledata_t mqueuefs_mod = {
2939 	"mqueuefs",
2940 	mq_modload,
2941 	&mqueuefs_vfsconf
2942 };
2943 DECLARE_MODULE(mqueuefs, mqueuefs_mod, SI_SUB_VFS, SI_ORDER_MIDDLE);
2944 MODULE_VERSION(mqueuefs, 1);
2945