xref: /freebsd/sys/kern/uipc_mqueue.c (revision 224e0c2f)
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 #include "opt_compat.h"
58 
59 #include <sys/param.h>
60 #include <sys/kernel.h>
61 #include <sys/systm.h>
62 #include <sys/limits.h>
63 #include <sys/malloc.h>
64 #include <sys/buf.h>
65 #include <sys/capsicum.h>
66 #include <sys/dirent.h>
67 #include <sys/event.h>
68 #include <sys/eventhandler.h>
69 #include <sys/fcntl.h>
70 #include <sys/file.h>
71 #include <sys/filedesc.h>
72 #include <sys/jail.h>
73 #include <sys/lock.h>
74 #include <sys/module.h>
75 #include <sys/mount.h>
76 #include <sys/mqueue.h>
77 #include <sys/mutex.h>
78 #include <sys/namei.h>
79 #include <sys/posix4.h>
80 #include <sys/poll.h>
81 #include <sys/priv.h>
82 #include <sys/proc.h>
83 #include <sys/queue.h>
84 #include <sys/sysproto.h>
85 #include <sys/stat.h>
86 #include <sys/syscall.h>
87 #include <sys/syscallsubr.h>
88 #include <sys/sysent.h>
89 #include <sys/sx.h>
90 #include <sys/sysctl.h>
91 #include <sys/taskqueue.h>
92 #include <sys/unistd.h>
93 #include <sys/user.h>
94 #include <sys/vnode.h>
95 #include <machine/atomic.h>
96 
97 #include <security/audit/audit.h>
98 
99 FEATURE(p1003_1b_mqueue, "POSIX P1003.1B message queues support");
100 
101 /*
102  * Limits and constants
103  */
104 #define	MQFS_NAMELEN		NAME_MAX
105 #define MQFS_DELEN		(8 + MQFS_NAMELEN)
106 
107 /* node types */
108 typedef enum {
109 	mqfstype_none = 0,
110 	mqfstype_root,
111 	mqfstype_dir,
112 	mqfstype_this,
113 	mqfstype_parent,
114 	mqfstype_file,
115 	mqfstype_symlink,
116 } mqfs_type_t;
117 
118 struct mqfs_node;
119 
120 /*
121  * mqfs_info: describes a mqfs instance
122  */
123 struct mqfs_info {
124 	struct sx		mi_lock;
125 	struct mqfs_node	*mi_root;
126 	struct unrhdr		*mi_unrhdr;
127 };
128 
129 struct mqfs_vdata {
130 	LIST_ENTRY(mqfs_vdata)	mv_link;
131 	struct mqfs_node	*mv_node;
132 	struct vnode		*mv_vnode;
133 	struct task		mv_task;
134 };
135 
136 /*
137  * mqfs_node: describes a node (file or directory) within a mqfs
138  */
139 struct mqfs_node {
140 	char			mn_name[MQFS_NAMELEN+1];
141 	struct mqfs_info	*mn_info;
142 	struct mqfs_node	*mn_parent;
143 	LIST_HEAD(,mqfs_node)	mn_children;
144 	LIST_ENTRY(mqfs_node)	mn_sibling;
145 	LIST_HEAD(,mqfs_vdata)	mn_vnodes;
146 	const void		*mn_pr_root;
147 	int			mn_refcount;
148 	mqfs_type_t		mn_type;
149 	int			mn_deleted;
150 	uint32_t		mn_fileno;
151 	void			*mn_data;
152 	struct timespec		mn_birth;
153 	struct timespec		mn_ctime;
154 	struct timespec		mn_atime;
155 	struct timespec		mn_mtime;
156 	uid_t			mn_uid;
157 	gid_t			mn_gid;
158 	int			mn_mode;
159 };
160 
161 #define	VTON(vp)	(((struct mqfs_vdata *)((vp)->v_data))->mv_node)
162 #define VTOMQ(vp) 	((struct mqueue *)(VTON(vp)->mn_data))
163 #define	VFSTOMQFS(m)	((struct mqfs_info *)((m)->mnt_data))
164 #define	FPTOMQ(fp)	((struct mqueue *)(((struct mqfs_node *) \
165 				(fp)->f_data)->mn_data))
166 
167 TAILQ_HEAD(msgq, mqueue_msg);
168 
169 struct mqueue;
170 
171 struct mqueue_notifier {
172 	LIST_ENTRY(mqueue_notifier)	nt_link;
173 	struct sigevent			nt_sigev;
174 	ksiginfo_t			nt_ksi;
175 	struct proc			*nt_proc;
176 };
177 
178 struct mqueue {
179 	struct mtx	mq_mutex;
180 	int		mq_flags;
181 	long		mq_maxmsg;
182 	long		mq_msgsize;
183 	long		mq_curmsgs;
184 	long		mq_totalbytes;
185 	struct msgq	mq_msgq;
186 	int		mq_receivers;
187 	int		mq_senders;
188 	struct selinfo	mq_rsel;
189 	struct selinfo	mq_wsel;
190 	struct mqueue_notifier	*mq_notifier;
191 };
192 
193 #define	MQ_RSEL		0x01
194 #define	MQ_WSEL		0x02
195 
196 struct mqueue_msg {
197 	TAILQ_ENTRY(mqueue_msg)	msg_link;
198 	unsigned int	msg_prio;
199 	unsigned int	msg_size;
200 	/* following real data... */
201 };
202 
203 static SYSCTL_NODE(_kern, OID_AUTO, mqueue, CTLFLAG_RW, 0,
204 	"POSIX real time message queue");
205 
206 static int	default_maxmsg  = 10;
207 static int	default_msgsize = 1024;
208 
209 static int	maxmsg = 100;
210 SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmsg, CTLFLAG_RW,
211     &maxmsg, 0, "Default maximum messages in queue");
212 static int	maxmsgsize = 16384;
213 SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmsgsize, CTLFLAG_RW,
214     &maxmsgsize, 0, "Default maximum message size");
215 static int	maxmq = 100;
216 SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmq, CTLFLAG_RW,
217     &maxmq, 0, "maximum message queues");
218 static int	curmq = 0;
219 SYSCTL_INT(_kern_mqueue, OID_AUTO, curmq, CTLFLAG_RW,
220     &curmq, 0, "current message queue number");
221 static int	unloadable = 0;
222 static MALLOC_DEFINE(M_MQUEUEDATA, "mqdata", "mqueue data");
223 
224 static eventhandler_tag exit_tag;
225 
226 /* Only one instance per-system */
227 static struct mqfs_info		mqfs_data;
228 static uma_zone_t		mqnode_zone;
229 static uma_zone_t		mqueue_zone;
230 static uma_zone_t		mvdata_zone;
231 static uma_zone_t		mqnoti_zone;
232 static struct vop_vector	mqfs_vnodeops;
233 static struct fileops		mqueueops;
234 static unsigned			mqfs_osd_jail_slot;
235 
236 /*
237  * Directory structure construction and manipulation
238  */
239 #ifdef notyet
240 static struct mqfs_node	*mqfs_create_dir(struct mqfs_node *parent,
241 	const char *name, int namelen, struct ucred *cred, int mode);
242 static struct mqfs_node	*mqfs_create_link(struct mqfs_node *parent,
243 	const char *name, int namelen, struct ucred *cred, int mode);
244 #endif
245 
246 static struct mqfs_node	*mqfs_create_file(struct mqfs_node *parent,
247 	const char *name, int namelen, struct ucred *cred, int mode);
248 static int	mqfs_destroy(struct mqfs_node *mn);
249 static void	mqfs_fileno_alloc(struct mqfs_info *mi, struct mqfs_node *mn);
250 static void	mqfs_fileno_free(struct mqfs_info *mi, struct mqfs_node *mn);
251 static int	mqfs_allocv(struct mount *mp, struct vnode **vpp, struct mqfs_node *pn);
252 static int	mqfs_prison_remove(void *obj, void *data);
253 
254 /*
255  * Message queue construction and maniplation
256  */
257 static struct mqueue	*mqueue_alloc(const struct mq_attr *attr);
258 static void	mqueue_free(struct mqueue *mq);
259 static int	mqueue_send(struct mqueue *mq, const char *msg_ptr,
260 			size_t msg_len, unsigned msg_prio, int waitok,
261 			const struct timespec *abs_timeout);
262 static int	mqueue_receive(struct mqueue *mq, char *msg_ptr,
263 			size_t msg_len, unsigned *msg_prio, int waitok,
264 			const struct timespec *abs_timeout);
265 static int	_mqueue_send(struct mqueue *mq, struct mqueue_msg *msg,
266 			int timo);
267 static int	_mqueue_recv(struct mqueue *mq, struct mqueue_msg **msg,
268 			int timo);
269 static void	mqueue_send_notification(struct mqueue *mq);
270 static void	mqueue_fdclose(struct thread *td, int fd, struct file *fp);
271 static void	mq_proc_exit(void *arg, struct proc *p);
272 
273 /*
274  * kqueue filters
275  */
276 static void	filt_mqdetach(struct knote *kn);
277 static int	filt_mqread(struct knote *kn, long hint);
278 static int	filt_mqwrite(struct knote *kn, long hint);
279 
280 struct filterops mq_rfiltops = {
281 	.f_isfd = 1,
282 	.f_detach = filt_mqdetach,
283 	.f_event = filt_mqread,
284 };
285 struct filterops mq_wfiltops = {
286 	.f_isfd = 1,
287 	.f_detach = filt_mqdetach,
288 	.f_event = filt_mqwrite,
289 };
290 
291 /*
292  * Initialize fileno bitmap
293  */
294 static void
295 mqfs_fileno_init(struct mqfs_info *mi)
296 {
297 	struct unrhdr *up;
298 
299 	up = new_unrhdr(1, INT_MAX, NULL);
300 	mi->mi_unrhdr = up;
301 }
302 
303 /*
304  * Tear down fileno bitmap
305  */
306 static void
307 mqfs_fileno_uninit(struct mqfs_info *mi)
308 {
309 	struct unrhdr *up;
310 
311 	up = mi->mi_unrhdr;
312 	mi->mi_unrhdr = NULL;
313 	delete_unrhdr(up);
314 }
315 
316 /*
317  * Allocate a file number
318  */
319 static void
320 mqfs_fileno_alloc(struct mqfs_info *mi, struct mqfs_node *mn)
321 {
322 	/* make sure our parent has a file number */
323 	if (mn->mn_parent && !mn->mn_parent->mn_fileno)
324 		mqfs_fileno_alloc(mi, mn->mn_parent);
325 
326 	switch (mn->mn_type) {
327 	case mqfstype_root:
328 	case mqfstype_dir:
329 	case mqfstype_file:
330 	case mqfstype_symlink:
331 		mn->mn_fileno = alloc_unr(mi->mi_unrhdr);
332 		break;
333 	case mqfstype_this:
334 		KASSERT(mn->mn_parent != NULL,
335 		    ("mqfstype_this node has no parent"));
336 		mn->mn_fileno = mn->mn_parent->mn_fileno;
337 		break;
338 	case mqfstype_parent:
339 		KASSERT(mn->mn_parent != NULL,
340 		    ("mqfstype_parent node has no parent"));
341 		if (mn->mn_parent == mi->mi_root) {
342 			mn->mn_fileno = mn->mn_parent->mn_fileno;
343 			break;
344 		}
345 		KASSERT(mn->mn_parent->mn_parent != NULL,
346 		    ("mqfstype_parent node has no grandparent"));
347 		mn->mn_fileno = mn->mn_parent->mn_parent->mn_fileno;
348 		break;
349 	default:
350 		KASSERT(0,
351 		    ("mqfs_fileno_alloc() called for unknown type node: %d",
352 			mn->mn_type));
353 		break;
354 	}
355 }
356 
357 /*
358  * Release a file number
359  */
360 static void
361 mqfs_fileno_free(struct mqfs_info *mi, struct mqfs_node *mn)
362 {
363 	switch (mn->mn_type) {
364 	case mqfstype_root:
365 	case mqfstype_dir:
366 	case mqfstype_file:
367 	case mqfstype_symlink:
368 		free_unr(mi->mi_unrhdr, mn->mn_fileno);
369 		break;
370 	case mqfstype_this:
371 	case mqfstype_parent:
372 		/* ignore these, as they don't "own" their file number */
373 		break;
374 	default:
375 		KASSERT(0,
376 		    ("mqfs_fileno_free() called for unknown type node: %d",
377 			mn->mn_type));
378 		break;
379 	}
380 }
381 
382 static __inline struct mqfs_node *
383 mqnode_alloc(void)
384 {
385 	return uma_zalloc(mqnode_zone, M_WAITOK | M_ZERO);
386 }
387 
388 static __inline void
389 mqnode_free(struct mqfs_node *node)
390 {
391 	uma_zfree(mqnode_zone, node);
392 }
393 
394 static __inline void
395 mqnode_addref(struct mqfs_node *node)
396 {
397 	atomic_fetchadd_int(&node->mn_refcount, 1);
398 }
399 
400 static __inline void
401 mqnode_release(struct mqfs_node *node)
402 {
403 	struct mqfs_info *mqfs;
404 	int old, exp;
405 
406 	mqfs = node->mn_info;
407 	old = atomic_fetchadd_int(&node->mn_refcount, -1);
408 	if (node->mn_type == mqfstype_dir ||
409 	    node->mn_type == mqfstype_root)
410 		exp = 3; /* include . and .. */
411 	else
412 		exp = 1;
413 	if (old == exp) {
414 		int locked = sx_xlocked(&mqfs->mi_lock);
415 		if (!locked)
416 			sx_xlock(&mqfs->mi_lock);
417 		mqfs_destroy(node);
418 		if (!locked)
419 			sx_xunlock(&mqfs->mi_lock);
420 	}
421 }
422 
423 /*
424  * Add a node to a directory
425  */
426 static int
427 mqfs_add_node(struct mqfs_node *parent, struct mqfs_node *node)
428 {
429 	KASSERT(parent != NULL, ("%s(): parent is NULL", __func__));
430 	KASSERT(parent->mn_info != NULL,
431 	    ("%s(): parent has no mn_info", __func__));
432 	KASSERT(parent->mn_type == mqfstype_dir ||
433 	    parent->mn_type == mqfstype_root,
434 	    ("%s(): parent is not a directory", __func__));
435 
436 	node->mn_info = parent->mn_info;
437 	node->mn_parent = parent;
438 	LIST_INIT(&node->mn_children);
439 	LIST_INIT(&node->mn_vnodes);
440 	LIST_INSERT_HEAD(&parent->mn_children, node, mn_sibling);
441 	mqnode_addref(parent);
442 	return (0);
443 }
444 
445 static struct mqfs_node *
446 mqfs_create_node(const char *name, int namelen, struct ucred *cred, int mode,
447 	int nodetype)
448 {
449 	struct mqfs_node *node;
450 
451 	node = mqnode_alloc();
452 	strncpy(node->mn_name, name, namelen);
453 	node->mn_pr_root = cred->cr_prison->pr_root;
454 	node->mn_type = nodetype;
455 	node->mn_refcount = 1;
456 	vfs_timestamp(&node->mn_birth);
457 	node->mn_ctime = node->mn_atime = node->mn_mtime
458 		= node->mn_birth;
459 	node->mn_uid = cred->cr_uid;
460 	node->mn_gid = cred->cr_gid;
461 	node->mn_mode = mode;
462 	return (node);
463 }
464 
465 /*
466  * Create a file
467  */
468 static struct mqfs_node *
469 mqfs_create_file(struct mqfs_node *parent, const char *name, int namelen,
470 	struct ucred *cred, int mode)
471 {
472 	struct mqfs_node *node;
473 
474 	node = mqfs_create_node(name, namelen, cred, mode, mqfstype_file);
475 	if (mqfs_add_node(parent, node) != 0) {
476 		mqnode_free(node);
477 		return (NULL);
478 	}
479 	return (node);
480 }
481 
482 /*
483  * Add . and .. to a directory
484  */
485 static int
486 mqfs_fixup_dir(struct mqfs_node *parent)
487 {
488 	struct mqfs_node *dir;
489 
490 	dir = mqnode_alloc();
491 	dir->mn_name[0] = '.';
492 	dir->mn_type = mqfstype_this;
493 	dir->mn_refcount = 1;
494 	if (mqfs_add_node(parent, dir) != 0) {
495 		mqnode_free(dir);
496 		return (-1);
497 	}
498 
499 	dir = mqnode_alloc();
500 	dir->mn_name[0] = dir->mn_name[1] = '.';
501 	dir->mn_type = mqfstype_parent;
502 	dir->mn_refcount = 1;
503 
504 	if (mqfs_add_node(parent, dir) != 0) {
505 		mqnode_free(dir);
506 		return (-1);
507 	}
508 
509 	return (0);
510 }
511 
512 #ifdef notyet
513 
514 /*
515  * Create a directory
516  */
517 static struct mqfs_node *
518 mqfs_create_dir(struct mqfs_node *parent, const char *name, int namelen,
519 	struct ucred *cred, int mode)
520 {
521 	struct mqfs_node *node;
522 
523 	node = mqfs_create_node(name, namelen, cred, mode, mqfstype_dir);
524 	if (mqfs_add_node(parent, node) != 0) {
525 		mqnode_free(node);
526 		return (NULL);
527 	}
528 
529 	if (mqfs_fixup_dir(node) != 0) {
530 		mqfs_destroy(node);
531 		return (NULL);
532 	}
533 	return (node);
534 }
535 
536 /*
537  * Create a symlink
538  */
539 static struct mqfs_node *
540 mqfs_create_link(struct mqfs_node *parent, const char *name, int namelen,
541 	struct ucred *cred, int mode)
542 {
543 	struct mqfs_node *node;
544 
545 	node = mqfs_create_node(name, namelen, cred, mode, mqfstype_symlink);
546 	if (mqfs_add_node(parent, node) != 0) {
547 		mqnode_free(node);
548 		return (NULL);
549 	}
550 	return (node);
551 }
552 
553 #endif
554 
555 /*
556  * Destroy a node or a tree of nodes
557  */
558 static int
559 mqfs_destroy(struct mqfs_node *node)
560 {
561 	struct mqfs_node *parent;
562 
563 	KASSERT(node != NULL,
564 	    ("%s(): node is NULL", __func__));
565 	KASSERT(node->mn_info != NULL,
566 	    ("%s(): node has no mn_info", __func__));
567 
568 	/* destroy children */
569 	if (node->mn_type == mqfstype_dir || node->mn_type == mqfstype_root)
570 		while (! LIST_EMPTY(&node->mn_children))
571 			mqfs_destroy(LIST_FIRST(&node->mn_children));
572 
573 	/* unlink from parent */
574 	if ((parent = node->mn_parent) != NULL) {
575 		KASSERT(parent->mn_info == node->mn_info,
576 		    ("%s(): parent has different mn_info", __func__));
577 		LIST_REMOVE(node, mn_sibling);
578 	}
579 
580 	if (node->mn_fileno != 0)
581 		mqfs_fileno_free(node->mn_info, node);
582 	if (node->mn_data != NULL)
583 		mqueue_free(node->mn_data);
584 	mqnode_free(node);
585 	return (0);
586 }
587 
588 /*
589  * Mount a mqfs instance
590  */
591 static int
592 mqfs_mount(struct mount *mp)
593 {
594 	struct statfs *sbp;
595 
596 	if (mp->mnt_flag & MNT_UPDATE)
597 		return (EOPNOTSUPP);
598 
599 	mp->mnt_data = &mqfs_data;
600 	MNT_ILOCK(mp);
601 	mp->mnt_flag |= MNT_LOCAL;
602 	MNT_IUNLOCK(mp);
603 	vfs_getnewfsid(mp);
604 
605 	sbp = &mp->mnt_stat;
606 	vfs_mountedfrom(mp, "mqueue");
607 	sbp->f_bsize = PAGE_SIZE;
608 	sbp->f_iosize = PAGE_SIZE;
609 	sbp->f_blocks = 1;
610 	sbp->f_bfree = 0;
611 	sbp->f_bavail = 0;
612 	sbp->f_files = 1;
613 	sbp->f_ffree = 0;
614 	return (0);
615 }
616 
617 /*
618  * Unmount a mqfs instance
619  */
620 static int
621 mqfs_unmount(struct mount *mp, int mntflags)
622 {
623 	int error;
624 
625 	error = vflush(mp, 0, (mntflags & MNT_FORCE) ?  FORCECLOSE : 0,
626 	    curthread);
627 	return (error);
628 }
629 
630 /*
631  * Return a root vnode
632  */
633 static int
634 mqfs_root(struct mount *mp, int flags, struct vnode **vpp)
635 {
636 	struct mqfs_info *mqfs;
637 	int ret;
638 
639 	mqfs = VFSTOMQFS(mp);
640 	ret = mqfs_allocv(mp, vpp, mqfs->mi_root);
641 	return (ret);
642 }
643 
644 /*
645  * Return filesystem stats
646  */
647 static int
648 mqfs_statfs(struct mount *mp, struct statfs *sbp)
649 {
650 	/* XXX update statistics */
651 	return (0);
652 }
653 
654 /*
655  * Initialize a mqfs instance
656  */
657 static int
658 mqfs_init(struct vfsconf *vfc)
659 {
660 	struct mqfs_node *root;
661 	struct mqfs_info *mi;
662 	osd_method_t methods[PR_MAXMETHOD] = {
663 	    [PR_METHOD_REMOVE] = mqfs_prison_remove,
664 	};
665 
666 	mqnode_zone = uma_zcreate("mqnode", sizeof(struct mqfs_node),
667 		NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
668 	mqueue_zone = uma_zcreate("mqueue", sizeof(struct mqueue),
669 		NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
670 	mvdata_zone = uma_zcreate("mvdata",
671 		sizeof(struct mqfs_vdata), NULL, NULL, NULL,
672 		NULL, UMA_ALIGN_PTR, 0);
673 	mqnoti_zone = uma_zcreate("mqnotifier", sizeof(struct mqueue_notifier),
674 		NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
675 	mi = &mqfs_data;
676 	sx_init(&mi->mi_lock, "mqfs lock");
677 	/* set up the root diretory */
678 	root = mqfs_create_node("/", 1, curthread->td_ucred, 01777,
679 		mqfstype_root);
680 	root->mn_info = mi;
681 	LIST_INIT(&root->mn_children);
682 	LIST_INIT(&root->mn_vnodes);
683 	mi->mi_root = root;
684 	mqfs_fileno_init(mi);
685 	mqfs_fileno_alloc(mi, root);
686 	mqfs_fixup_dir(root);
687 	exit_tag = EVENTHANDLER_REGISTER(process_exit, mq_proc_exit, NULL,
688 	    EVENTHANDLER_PRI_ANY);
689 	mq_fdclose = mqueue_fdclose;
690 	p31b_setcfg(CTL_P1003_1B_MESSAGE_PASSING, _POSIX_MESSAGE_PASSING);
691 	mqfs_osd_jail_slot = osd_jail_register(NULL, methods);
692 	return (0);
693 }
694 
695 /*
696  * Destroy a mqfs instance
697  */
698 static int
699 mqfs_uninit(struct vfsconf *vfc)
700 {
701 	struct mqfs_info *mi;
702 
703 	if (!unloadable)
704 		return (EOPNOTSUPP);
705 	osd_jail_deregister(mqfs_osd_jail_slot);
706 	EVENTHANDLER_DEREGISTER(process_exit, exit_tag);
707 	mi = &mqfs_data;
708 	mqfs_destroy(mi->mi_root);
709 	mi->mi_root = NULL;
710 	mqfs_fileno_uninit(mi);
711 	sx_destroy(&mi->mi_lock);
712 	uma_zdestroy(mqnode_zone);
713 	uma_zdestroy(mqueue_zone);
714 	uma_zdestroy(mvdata_zone);
715 	uma_zdestroy(mqnoti_zone);
716 	return (0);
717 }
718 
719 /*
720  * task routine
721  */
722 static void
723 do_recycle(void *context, int pending __unused)
724 {
725 	struct vnode *vp = (struct vnode *)context;
726 
727 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
728 	vrecycle(vp);
729 	VOP_UNLOCK(vp, 0);
730 	vdrop(vp);
731 }
732 
733 /*
734  * Allocate a vnode
735  */
736 static int
737 mqfs_allocv(struct mount *mp, struct vnode **vpp, struct mqfs_node *pn)
738 {
739 	struct mqfs_vdata *vd;
740 	struct mqfs_info  *mqfs;
741 	struct vnode *newvpp;
742 	int error;
743 
744 	mqfs = pn->mn_info;
745 	*vpp = NULL;
746 	sx_xlock(&mqfs->mi_lock);
747 	LIST_FOREACH(vd, &pn->mn_vnodes, mv_link) {
748 		if (vd->mv_vnode->v_mount == mp) {
749 			vhold(vd->mv_vnode);
750 			break;
751 		}
752 	}
753 
754 	if (vd != NULL) {
755 found:
756 		*vpp = vd->mv_vnode;
757 		sx_xunlock(&mqfs->mi_lock);
758 		error = vget(*vpp, LK_RETRY | LK_EXCLUSIVE, curthread);
759 		vdrop(*vpp);
760 		return (error);
761 	}
762 	sx_xunlock(&mqfs->mi_lock);
763 
764 	error = getnewvnode("mqueue", mp, &mqfs_vnodeops, &newvpp);
765 	if (error)
766 		return (error);
767 	vn_lock(newvpp, LK_EXCLUSIVE | LK_RETRY);
768 	error = insmntque(newvpp, mp);
769 	if (error != 0)
770 		return (error);
771 
772 	sx_xlock(&mqfs->mi_lock);
773 	/*
774 	 * Check if it has already been allocated
775 	 * while we were blocked.
776 	 */
777 	LIST_FOREACH(vd, &pn->mn_vnodes, mv_link) {
778 		if (vd->mv_vnode->v_mount == mp) {
779 			vhold(vd->mv_vnode);
780 			sx_xunlock(&mqfs->mi_lock);
781 
782 			vgone(newvpp);
783 			vput(newvpp);
784 			goto found;
785 		}
786 	}
787 
788 	*vpp = newvpp;
789 
790 	vd = uma_zalloc(mvdata_zone, M_WAITOK);
791 	(*vpp)->v_data = vd;
792 	vd->mv_vnode = *vpp;
793 	vd->mv_node = pn;
794 	TASK_INIT(&vd->mv_task, 0, do_recycle, *vpp);
795 	LIST_INSERT_HEAD(&pn->mn_vnodes, vd, mv_link);
796 	mqnode_addref(pn);
797 	switch (pn->mn_type) {
798 	case mqfstype_root:
799 		(*vpp)->v_vflag = VV_ROOT;
800 		/* fall through */
801 	case mqfstype_dir:
802 	case mqfstype_this:
803 	case mqfstype_parent:
804 		(*vpp)->v_type = VDIR;
805 		break;
806 	case mqfstype_file:
807 		(*vpp)->v_type = VREG;
808 		break;
809 	case mqfstype_symlink:
810 		(*vpp)->v_type = VLNK;
811 		break;
812 	case mqfstype_none:
813 		KASSERT(0, ("mqfs_allocf called for null node\n"));
814 	default:
815 		panic("%s has unexpected type: %d", pn->mn_name, pn->mn_type);
816 	}
817 	sx_xunlock(&mqfs->mi_lock);
818 	return (0);
819 }
820 
821 /*
822  * Search a directory entry
823  */
824 static struct mqfs_node *
825 mqfs_search(struct mqfs_node *pd, const char *name, int len, struct ucred *cred)
826 {
827 	struct mqfs_node *pn;
828 	const void *pr_root;
829 
830 	sx_assert(&pd->mn_info->mi_lock, SX_LOCKED);
831 	pr_root = cred->cr_prison->pr_root;
832 	LIST_FOREACH(pn, &pd->mn_children, mn_sibling) {
833 		/* Only match names within the same prison root directory */
834 		if ((pn->mn_pr_root == NULL || pn->mn_pr_root == pr_root) &&
835 		    strncmp(pn->mn_name, name, len) == 0 &&
836 		    pn->mn_name[len] == '\0')
837 			return (pn);
838 	}
839 	return (NULL);
840 }
841 
842 /*
843  * Look up a file or directory.
844  */
845 static int
846 mqfs_lookupx(struct vop_cachedlookup_args *ap)
847 {
848 	struct componentname *cnp;
849 	struct vnode *dvp, **vpp;
850 	struct mqfs_node *pd;
851 	struct mqfs_node *pn;
852 	struct mqfs_info *mqfs;
853 	int nameiop, flags, error, namelen;
854 	char *pname;
855 	struct thread *td;
856 
857 	cnp = ap->a_cnp;
858 	vpp = ap->a_vpp;
859 	dvp = ap->a_dvp;
860 	pname = cnp->cn_nameptr;
861 	namelen = cnp->cn_namelen;
862 	td = cnp->cn_thread;
863 	flags = cnp->cn_flags;
864 	nameiop = cnp->cn_nameiop;
865 	pd = VTON(dvp);
866 	pn = NULL;
867 	mqfs = pd->mn_info;
868 	*vpp = NULLVP;
869 
870 	if (dvp->v_type != VDIR)
871 		return (ENOTDIR);
872 
873 	error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, cnp->cn_thread);
874 	if (error)
875 		return (error);
876 
877 	/* shortcut: check if the name is too long */
878 	if (cnp->cn_namelen >= MQFS_NAMELEN)
879 		return (ENOENT);
880 
881 	/* self */
882 	if (namelen == 1 && pname[0] == '.') {
883 		if ((flags & ISLASTCN) && nameiop != LOOKUP)
884 			return (EINVAL);
885 		pn = pd;
886 		*vpp = dvp;
887 		VREF(dvp);
888 		return (0);
889 	}
890 
891 	/* parent */
892 	if (cnp->cn_flags & ISDOTDOT) {
893 		if (dvp->v_vflag & VV_ROOT)
894 			return (EIO);
895 		if ((flags & ISLASTCN) && nameiop != LOOKUP)
896 			return (EINVAL);
897 		VOP_UNLOCK(dvp, 0);
898 		KASSERT(pd->mn_parent, ("non-root directory has no parent"));
899 		pn = pd->mn_parent;
900 		error = mqfs_allocv(dvp->v_mount, vpp, pn);
901 		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
902 		return (error);
903 	}
904 
905 	/* named node */
906 	sx_xlock(&mqfs->mi_lock);
907 	pn = mqfs_search(pd, pname, namelen, cnp->cn_cred);
908 	if (pn != NULL)
909 		mqnode_addref(pn);
910 	sx_xunlock(&mqfs->mi_lock);
911 
912 	/* found */
913 	if (pn != NULL) {
914 		/* DELETE */
915 		if (nameiop == DELETE && (flags & ISLASTCN)) {
916 			error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td);
917 			if (error) {
918 				mqnode_release(pn);
919 				return (error);
920 			}
921 			if (*vpp == dvp) {
922 				VREF(dvp);
923 				*vpp = dvp;
924 				mqnode_release(pn);
925 				return (0);
926 			}
927 		}
928 
929 		/* allocate vnode */
930 		error = mqfs_allocv(dvp->v_mount, vpp, pn);
931 		mqnode_release(pn);
932 		if (error == 0 && cnp->cn_flags & MAKEENTRY)
933 			cache_enter(dvp, *vpp, cnp);
934 		return (error);
935 	}
936 
937 	/* not found */
938 
939 	/* will create a new entry in the directory ? */
940 	if ((nameiop == CREATE || nameiop == RENAME) && (flags & LOCKPARENT)
941 	    && (flags & ISLASTCN)) {
942 		error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td);
943 		if (error)
944 			return (error);
945 		cnp->cn_flags |= SAVENAME;
946 		return (EJUSTRETURN);
947 	}
948 	return (ENOENT);
949 }
950 
951 #if 0
952 struct vop_lookup_args {
953 	struct vop_generic_args a_gen;
954 	struct vnode *a_dvp;
955 	struct vnode **a_vpp;
956 	struct componentname *a_cnp;
957 };
958 #endif
959 
960 /*
961  * vnode lookup operation
962  */
963 static int
964 mqfs_lookup(struct vop_cachedlookup_args *ap)
965 {
966 	int rc;
967 
968 	rc = mqfs_lookupx(ap);
969 	return (rc);
970 }
971 
972 #if 0
973 struct vop_create_args {
974 	struct vnode *a_dvp;
975 	struct vnode **a_vpp;
976 	struct componentname *a_cnp;
977 	struct vattr *a_vap;
978 };
979 #endif
980 
981 /*
982  * vnode creation operation
983  */
984 static int
985 mqfs_create(struct vop_create_args *ap)
986 {
987 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount);
988 	struct componentname *cnp = ap->a_cnp;
989 	struct mqfs_node *pd;
990 	struct mqfs_node *pn;
991 	struct mqueue *mq;
992 	int error;
993 
994 	pd = VTON(ap->a_dvp);
995 	if (pd->mn_type != mqfstype_root && pd->mn_type != mqfstype_dir)
996 		return (ENOTDIR);
997 	mq = mqueue_alloc(NULL);
998 	if (mq == NULL)
999 		return (EAGAIN);
1000 	sx_xlock(&mqfs->mi_lock);
1001 	if ((cnp->cn_flags & HASBUF) == 0)
1002 		panic("%s: no name", __func__);
1003 	pn = mqfs_create_file(pd, cnp->cn_nameptr, cnp->cn_namelen,
1004 		cnp->cn_cred, ap->a_vap->va_mode);
1005 	if (pn == NULL) {
1006 		sx_xunlock(&mqfs->mi_lock);
1007 		error = ENOSPC;
1008 	} else {
1009 		mqnode_addref(pn);
1010 		sx_xunlock(&mqfs->mi_lock);
1011 		error = mqfs_allocv(ap->a_dvp->v_mount, ap->a_vpp, pn);
1012 		mqnode_release(pn);
1013 		if (error)
1014 			mqfs_destroy(pn);
1015 		else
1016 			pn->mn_data = mq;
1017 	}
1018 	if (error)
1019 		mqueue_free(mq);
1020 	return (error);
1021 }
1022 
1023 /*
1024  * Remove an entry
1025  */
1026 static
1027 int do_unlink(struct mqfs_node *pn, struct ucred *ucred)
1028 {
1029 	struct mqfs_node *parent;
1030 	struct mqfs_vdata *vd;
1031 	int error = 0;
1032 
1033 	sx_assert(&pn->mn_info->mi_lock, SX_LOCKED);
1034 
1035 	if (ucred->cr_uid != pn->mn_uid &&
1036 	    (error = priv_check_cred(ucred, PRIV_MQ_ADMIN, 0)) != 0)
1037 		error = EACCES;
1038 	else if (!pn->mn_deleted) {
1039 		parent = pn->mn_parent;
1040 		pn->mn_parent = NULL;
1041 		pn->mn_deleted = 1;
1042 		LIST_REMOVE(pn, mn_sibling);
1043 		LIST_FOREACH(vd, &pn->mn_vnodes, mv_link) {
1044 			cache_purge(vd->mv_vnode);
1045 			vhold(vd->mv_vnode);
1046 			taskqueue_enqueue(taskqueue_thread, &vd->mv_task);
1047 		}
1048 		mqnode_release(pn);
1049 		mqnode_release(parent);
1050 	} else
1051 		error = ENOENT;
1052 	return (error);
1053 }
1054 
1055 #if 0
1056 struct vop_remove_args {
1057 	struct vnode *a_dvp;
1058 	struct vnode *a_vp;
1059 	struct componentname *a_cnp;
1060 };
1061 #endif
1062 
1063 /*
1064  * vnode removal operation
1065  */
1066 static int
1067 mqfs_remove(struct vop_remove_args *ap)
1068 {
1069 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount);
1070 	struct mqfs_node *pn;
1071 	int error;
1072 
1073 	if (ap->a_vp->v_type == VDIR)
1074                 return (EPERM);
1075 	pn = VTON(ap->a_vp);
1076 	sx_xlock(&mqfs->mi_lock);
1077 	error = do_unlink(pn, ap->a_cnp->cn_cred);
1078 	sx_xunlock(&mqfs->mi_lock);
1079 	return (error);
1080 }
1081 
1082 #if 0
1083 struct vop_inactive_args {
1084 	struct vnode *a_vp;
1085 	struct thread *a_td;
1086 };
1087 #endif
1088 
1089 static int
1090 mqfs_inactive(struct vop_inactive_args *ap)
1091 {
1092 	struct mqfs_node *pn = VTON(ap->a_vp);
1093 
1094 	if (pn->mn_deleted)
1095 		vrecycle(ap->a_vp);
1096 	return (0);
1097 }
1098 
1099 #if 0
1100 struct vop_reclaim_args {
1101 	struct vop_generic_args a_gen;
1102 	struct vnode *a_vp;
1103 	struct thread *a_td;
1104 };
1105 #endif
1106 
1107 static int
1108 mqfs_reclaim(struct vop_reclaim_args *ap)
1109 {
1110 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_vp->v_mount);
1111 	struct vnode *vp = ap->a_vp;
1112 	struct mqfs_node *pn;
1113 	struct mqfs_vdata *vd;
1114 
1115 	vd = vp->v_data;
1116 	pn = vd->mv_node;
1117 	sx_xlock(&mqfs->mi_lock);
1118 	vp->v_data = NULL;
1119 	LIST_REMOVE(vd, mv_link);
1120 	uma_zfree(mvdata_zone, vd);
1121 	mqnode_release(pn);
1122 	sx_xunlock(&mqfs->mi_lock);
1123 	return (0);
1124 }
1125 
1126 #if 0
1127 struct vop_open_args {
1128 	struct vop_generic_args a_gen;
1129 	struct vnode *a_vp;
1130 	int a_mode;
1131 	struct ucred *a_cred;
1132 	struct thread *a_td;
1133 	struct file *a_fp;
1134 };
1135 #endif
1136 
1137 static int
1138 mqfs_open(struct vop_open_args *ap)
1139 {
1140 	return (0);
1141 }
1142 
1143 #if 0
1144 struct vop_close_args {
1145 	struct vop_generic_args a_gen;
1146 	struct vnode *a_vp;
1147 	int a_fflag;
1148 	struct ucred *a_cred;
1149 	struct thread *a_td;
1150 };
1151 #endif
1152 
1153 static int
1154 mqfs_close(struct vop_close_args *ap)
1155 {
1156 	return (0);
1157 }
1158 
1159 #if 0
1160 struct vop_access_args {
1161 	struct vop_generic_args a_gen;
1162 	struct vnode *a_vp;
1163 	accmode_t a_accmode;
1164 	struct ucred *a_cred;
1165 	struct thread *a_td;
1166 };
1167 #endif
1168 
1169 /*
1170  * Verify permissions
1171  */
1172 static int
1173 mqfs_access(struct vop_access_args *ap)
1174 {
1175 	struct vnode *vp = ap->a_vp;
1176 	struct vattr vattr;
1177 	int error;
1178 
1179 	error = VOP_GETATTR(vp, &vattr, ap->a_cred);
1180 	if (error)
1181 		return (error);
1182 	error = vaccess(vp->v_type, vattr.va_mode, vattr.va_uid,
1183 	    vattr.va_gid, ap->a_accmode, ap->a_cred, NULL);
1184 	return (error);
1185 }
1186 
1187 #if 0
1188 struct vop_getattr_args {
1189 	struct vop_generic_args a_gen;
1190 	struct vnode *a_vp;
1191 	struct vattr *a_vap;
1192 	struct ucred *a_cred;
1193 };
1194 #endif
1195 
1196 /*
1197  * Get file attributes
1198  */
1199 static int
1200 mqfs_getattr(struct vop_getattr_args *ap)
1201 {
1202 	struct vnode *vp = ap->a_vp;
1203 	struct mqfs_node *pn = VTON(vp);
1204 	struct vattr *vap = ap->a_vap;
1205 	int error = 0;
1206 
1207 	vap->va_type = vp->v_type;
1208 	vap->va_mode = pn->mn_mode;
1209 	vap->va_nlink = 1;
1210 	vap->va_uid = pn->mn_uid;
1211 	vap->va_gid = pn->mn_gid;
1212 	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
1213 	vap->va_fileid = pn->mn_fileno;
1214 	vap->va_size = 0;
1215 	vap->va_blocksize = PAGE_SIZE;
1216 	vap->va_bytes = vap->va_size = 0;
1217 	vap->va_atime = pn->mn_atime;
1218 	vap->va_mtime = pn->mn_mtime;
1219 	vap->va_ctime = pn->mn_ctime;
1220 	vap->va_birthtime = pn->mn_birth;
1221 	vap->va_gen = 0;
1222 	vap->va_flags = 0;
1223 	vap->va_rdev = NODEV;
1224 	vap->va_bytes = 0;
1225 	vap->va_filerev = 0;
1226 	return (error);
1227 }
1228 
1229 #if 0
1230 struct vop_setattr_args {
1231 	struct vop_generic_args a_gen;
1232 	struct vnode *a_vp;
1233 	struct vattr *a_vap;
1234 	struct ucred *a_cred;
1235 };
1236 #endif
1237 /*
1238  * Set attributes
1239  */
1240 static int
1241 mqfs_setattr(struct vop_setattr_args *ap)
1242 {
1243 	struct mqfs_node *pn;
1244 	struct vattr *vap;
1245 	struct vnode *vp;
1246 	struct thread *td;
1247 	int c, error;
1248 	uid_t uid;
1249 	gid_t gid;
1250 
1251 	td = curthread;
1252 	vap = ap->a_vap;
1253 	vp = ap->a_vp;
1254 	if ((vap->va_type != VNON) ||
1255 	    (vap->va_nlink != VNOVAL) ||
1256 	    (vap->va_fsid != VNOVAL) ||
1257 	    (vap->va_fileid != VNOVAL) ||
1258 	    (vap->va_blocksize != VNOVAL) ||
1259 	    (vap->va_flags != VNOVAL && vap->va_flags != 0) ||
1260 	    (vap->va_rdev != VNOVAL) ||
1261 	    ((int)vap->va_bytes != VNOVAL) ||
1262 	    (vap->va_gen != VNOVAL)) {
1263 		return (EINVAL);
1264 	}
1265 
1266 	pn = VTON(vp);
1267 
1268 	error = c = 0;
1269 	if (vap->va_uid == (uid_t)VNOVAL)
1270 		uid = pn->mn_uid;
1271 	else
1272 		uid = vap->va_uid;
1273 	if (vap->va_gid == (gid_t)VNOVAL)
1274 		gid = pn->mn_gid;
1275 	else
1276 		gid = vap->va_gid;
1277 
1278 	if (uid != pn->mn_uid || gid != pn->mn_gid) {
1279 		/*
1280 		 * To modify the ownership of a file, must possess VADMIN
1281 		 * for that file.
1282 		 */
1283 		if ((error = VOP_ACCESS(vp, VADMIN, ap->a_cred, td)))
1284 			return (error);
1285 
1286 		/*
1287 		 * XXXRW: Why is there a privilege check here: shouldn't the
1288 		 * check in VOP_ACCESS() be enough?  Also, are the group bits
1289 		 * below definitely right?
1290 		 */
1291 		if (((ap->a_cred->cr_uid != pn->mn_uid) || uid != pn->mn_uid ||
1292 		    (gid != pn->mn_gid && !groupmember(gid, ap->a_cred))) &&
1293 		    (error = priv_check(td, PRIV_MQ_ADMIN)) != 0)
1294 			return (error);
1295 		pn->mn_uid = uid;
1296 		pn->mn_gid = gid;
1297 		c = 1;
1298 	}
1299 
1300 	if (vap->va_mode != (mode_t)VNOVAL) {
1301 		if ((ap->a_cred->cr_uid != pn->mn_uid) &&
1302 		    (error = priv_check(td, PRIV_MQ_ADMIN)))
1303 			return (error);
1304 		pn->mn_mode = vap->va_mode;
1305 		c = 1;
1306 	}
1307 
1308 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
1309 		/* See the comment in ufs_vnops::ufs_setattr(). */
1310 		if ((error = VOP_ACCESS(vp, VADMIN, ap->a_cred, td)) &&
1311 		    ((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
1312 		    (error = VOP_ACCESS(vp, VWRITE, ap->a_cred, td))))
1313 			return (error);
1314 		if (vap->va_atime.tv_sec != VNOVAL) {
1315 			pn->mn_atime = vap->va_atime;
1316 		}
1317 		if (vap->va_mtime.tv_sec != VNOVAL) {
1318 			pn->mn_mtime = vap->va_mtime;
1319 		}
1320 		c = 1;
1321 	}
1322 	if (c) {
1323 		vfs_timestamp(&pn->mn_ctime);
1324 	}
1325 	return (0);
1326 }
1327 
1328 #if 0
1329 struct vop_read_args {
1330 	struct vop_generic_args a_gen;
1331 	struct vnode *a_vp;
1332 	struct uio *a_uio;
1333 	int a_ioflag;
1334 	struct ucred *a_cred;
1335 };
1336 #endif
1337 
1338 /*
1339  * Read from a file
1340  */
1341 static int
1342 mqfs_read(struct vop_read_args *ap)
1343 {
1344 	char buf[80];
1345 	struct vnode *vp = ap->a_vp;
1346 	struct uio *uio = ap->a_uio;
1347 	struct mqfs_node *pn;
1348 	struct mqueue *mq;
1349 	int len, error;
1350 
1351 	if (vp->v_type != VREG)
1352 		return (EINVAL);
1353 
1354 	pn = VTON(vp);
1355 	mq = VTOMQ(vp);
1356 	snprintf(buf, sizeof(buf),
1357 		"QSIZE:%-10ld MAXMSG:%-10ld CURMSG:%-10ld MSGSIZE:%-10ld\n",
1358 		mq->mq_totalbytes,
1359 		mq->mq_maxmsg,
1360 		mq->mq_curmsgs,
1361 		mq->mq_msgsize);
1362 	buf[sizeof(buf)-1] = '\0';
1363 	len = strlen(buf);
1364 	error = uiomove_frombuf(buf, len, uio);
1365 	return (error);
1366 }
1367 
1368 #if 0
1369 struct vop_readdir_args {
1370 	struct vop_generic_args a_gen;
1371 	struct vnode *a_vp;
1372 	struct uio *a_uio;
1373 	struct ucred *a_cred;
1374 	int *a_eofflag;
1375 	int *a_ncookies;
1376 	u_long **a_cookies;
1377 };
1378 #endif
1379 
1380 /*
1381  * Return directory entries.
1382  */
1383 static int
1384 mqfs_readdir(struct vop_readdir_args *ap)
1385 {
1386 	struct vnode *vp;
1387 	struct mqfs_info *mi;
1388 	struct mqfs_node *pd;
1389 	struct mqfs_node *pn;
1390 	struct dirent entry;
1391 	struct uio *uio;
1392 	const void *pr_root;
1393 	int *tmp_ncookies = NULL;
1394 	off_t offset;
1395 	int error, i;
1396 
1397 	vp = ap->a_vp;
1398 	mi = VFSTOMQFS(vp->v_mount);
1399 	pd = VTON(vp);
1400 	uio = ap->a_uio;
1401 
1402 	if (vp->v_type != VDIR)
1403 		return (ENOTDIR);
1404 
1405 	if (uio->uio_offset < 0)
1406 		return (EINVAL);
1407 
1408 	if (ap->a_ncookies != NULL) {
1409 		tmp_ncookies = ap->a_ncookies;
1410 		*ap->a_ncookies = 0;
1411 		ap->a_ncookies = NULL;
1412         }
1413 
1414 	error = 0;
1415 	offset = 0;
1416 
1417 	pr_root = ap->a_cred->cr_prison->pr_root;
1418 	sx_xlock(&mi->mi_lock);
1419 
1420 	LIST_FOREACH(pn, &pd->mn_children, mn_sibling) {
1421 		entry.d_reclen = sizeof(entry);
1422 
1423 		/*
1424 		 * Only show names within the same prison root directory
1425 		 * (or not associated with a prison, e.g. "." and "..").
1426 		 */
1427 		if (pn->mn_pr_root != NULL && pn->mn_pr_root != pr_root)
1428 			continue;
1429 		if (!pn->mn_fileno)
1430 			mqfs_fileno_alloc(mi, pn);
1431 		entry.d_fileno = pn->mn_fileno;
1432 		for (i = 0; i < MQFS_NAMELEN - 1 && pn->mn_name[i] != '\0'; ++i)
1433 			entry.d_name[i] = pn->mn_name[i];
1434 		entry.d_name[i] = 0;
1435 		entry.d_namlen = i;
1436 		switch (pn->mn_type) {
1437 		case mqfstype_root:
1438 		case mqfstype_dir:
1439 		case mqfstype_this:
1440 		case mqfstype_parent:
1441 			entry.d_type = DT_DIR;
1442 			break;
1443 		case mqfstype_file:
1444 			entry.d_type = DT_REG;
1445 			break;
1446 		case mqfstype_symlink:
1447 			entry.d_type = DT_LNK;
1448 			break;
1449 		default:
1450 			panic("%s has unexpected node type: %d", pn->mn_name,
1451 				pn->mn_type);
1452 		}
1453 		if (entry.d_reclen > uio->uio_resid)
1454                         break;
1455 		if (offset >= uio->uio_offset) {
1456 			error = vfs_read_dirent(ap, &entry, offset);
1457                         if (error)
1458                                 break;
1459                 }
1460                 offset += entry.d_reclen;
1461 	}
1462 	sx_xunlock(&mi->mi_lock);
1463 
1464 	uio->uio_offset = offset;
1465 
1466 	if (tmp_ncookies != NULL)
1467 		ap->a_ncookies = tmp_ncookies;
1468 
1469 	return (error);
1470 }
1471 
1472 #ifdef notyet
1473 
1474 #if 0
1475 struct vop_mkdir_args {
1476 	struct vnode *a_dvp;
1477 	struvt vnode **a_vpp;
1478 	struvt componentname *a_cnp;
1479 	struct vattr *a_vap;
1480 };
1481 #endif
1482 
1483 /*
1484  * Create a directory.
1485  */
1486 static int
1487 mqfs_mkdir(struct vop_mkdir_args *ap)
1488 {
1489 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount);
1490 	struct componentname *cnp = ap->a_cnp;
1491 	struct mqfs_node *pd = VTON(ap->a_dvp);
1492 	struct mqfs_node *pn;
1493 	int error;
1494 
1495 	if (pd->mn_type != mqfstype_root && pd->mn_type != mqfstype_dir)
1496 		return (ENOTDIR);
1497 	sx_xlock(&mqfs->mi_lock);
1498 	if ((cnp->cn_flags & HASBUF) == 0)
1499 		panic("%s: no name", __func__);
1500 	pn = mqfs_create_dir(pd, cnp->cn_nameptr, cnp->cn_namelen,
1501 		ap->a_vap->cn_cred, ap->a_vap->va_mode);
1502 	if (pn != NULL)
1503 		mqnode_addref(pn);
1504 	sx_xunlock(&mqfs->mi_lock);
1505 	if (pn == NULL) {
1506 		error = ENOSPC;
1507 	} else {
1508 		error = mqfs_allocv(ap->a_dvp->v_mount, ap->a_vpp, pn);
1509 		mqnode_release(pn);
1510 	}
1511 	return (error);
1512 }
1513 
1514 #if 0
1515 struct vop_rmdir_args {
1516 	struct vnode *a_dvp;
1517 	struct vnode *a_vp;
1518 	struct componentname *a_cnp;
1519 };
1520 #endif
1521 
1522 /*
1523  * Remove a directory.
1524  */
1525 static int
1526 mqfs_rmdir(struct vop_rmdir_args *ap)
1527 {
1528 	struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount);
1529 	struct mqfs_node *pn = VTON(ap->a_vp);
1530 	struct mqfs_node *pt;
1531 
1532 	if (pn->mn_type != mqfstype_dir)
1533 		return (ENOTDIR);
1534 
1535 	sx_xlock(&mqfs->mi_lock);
1536 	if (pn->mn_deleted) {
1537 		sx_xunlock(&mqfs->mi_lock);
1538 		return (ENOENT);
1539 	}
1540 
1541 	pt = LIST_FIRST(&pn->mn_children);
1542 	pt = LIST_NEXT(pt, mn_sibling);
1543 	pt = LIST_NEXT(pt, mn_sibling);
1544 	if (pt != NULL) {
1545 		sx_xunlock(&mqfs->mi_lock);
1546 		return (ENOTEMPTY);
1547 	}
1548 	pt = pn->mn_parent;
1549 	pn->mn_parent = NULL;
1550 	pn->mn_deleted = 1;
1551 	LIST_REMOVE(pn, mn_sibling);
1552 	mqnode_release(pn);
1553 	mqnode_release(pt);
1554 	sx_xunlock(&mqfs->mi_lock);
1555 	cache_purge(ap->a_vp);
1556 	return (0);
1557 }
1558 
1559 #endif /* notyet */
1560 
1561 /*
1562  * See if this prison root is obsolete, and clean up associated queues if it is.
1563  */
1564 static int
1565 mqfs_prison_remove(void *obj, void *data __unused)
1566 {
1567 	const struct prison *pr = obj;
1568 	const struct prison *tpr;
1569 	struct mqfs_node *pn, *tpn;
1570 	int found;
1571 
1572 	found = 0;
1573 	TAILQ_FOREACH(tpr, &allprison, pr_list) {
1574 		if (tpr->pr_root == pr->pr_root && tpr != pr && tpr->pr_ref > 0)
1575 			found = 1;
1576 	}
1577 	if (!found) {
1578 		/*
1579 		 * No jails are rooted in this directory anymore,
1580 		 * so no queues should be either.
1581 		 */
1582 		sx_xlock(&mqfs_data.mi_lock);
1583 		LIST_FOREACH_SAFE(pn, &mqfs_data.mi_root->mn_children,
1584 		    mn_sibling, tpn) {
1585 			if (pn->mn_pr_root == pr->pr_root)
1586 				(void)do_unlink(pn, curthread->td_ucred);
1587 		}
1588 		sx_xunlock(&mqfs_data.mi_lock);
1589 	}
1590 	return (0);
1591 }
1592 
1593 /*
1594  * Allocate a message queue
1595  */
1596 static struct mqueue *
1597 mqueue_alloc(const struct mq_attr *attr)
1598 {
1599 	struct mqueue *mq;
1600 
1601 	if (curmq >= maxmq)
1602 		return (NULL);
1603 	mq = uma_zalloc(mqueue_zone, M_WAITOK | M_ZERO);
1604 	TAILQ_INIT(&mq->mq_msgq);
1605 	if (attr != NULL) {
1606 		mq->mq_maxmsg = attr->mq_maxmsg;
1607 		mq->mq_msgsize = attr->mq_msgsize;
1608 	} else {
1609 		mq->mq_maxmsg = default_maxmsg;
1610 		mq->mq_msgsize = default_msgsize;
1611 	}
1612 	mtx_init(&mq->mq_mutex, "mqueue lock", NULL, MTX_DEF);
1613 	knlist_init_mtx(&mq->mq_rsel.si_note, &mq->mq_mutex);
1614 	knlist_init_mtx(&mq->mq_wsel.si_note, &mq->mq_mutex);
1615 	atomic_add_int(&curmq, 1);
1616 	return (mq);
1617 }
1618 
1619 /*
1620  * Destroy a message queue
1621  */
1622 static void
1623 mqueue_free(struct mqueue *mq)
1624 {
1625 	struct mqueue_msg *msg;
1626 
1627 	while ((msg = TAILQ_FIRST(&mq->mq_msgq)) != NULL) {
1628 		TAILQ_REMOVE(&mq->mq_msgq, msg, msg_link);
1629 		free(msg, M_MQUEUEDATA);
1630 	}
1631 
1632 	mtx_destroy(&mq->mq_mutex);
1633 	seldrain(&mq->mq_rsel);
1634 	seldrain(&mq->mq_wsel);
1635 	knlist_destroy(&mq->mq_rsel.si_note);
1636 	knlist_destroy(&mq->mq_wsel.si_note);
1637 	uma_zfree(mqueue_zone, mq);
1638 	atomic_add_int(&curmq, -1);
1639 }
1640 
1641 /*
1642  * Load a message from user space
1643  */
1644 static struct mqueue_msg *
1645 mqueue_loadmsg(const char *msg_ptr, size_t msg_size, int msg_prio)
1646 {
1647 	struct mqueue_msg *msg;
1648 	size_t len;
1649 	int error;
1650 
1651 	len = sizeof(struct mqueue_msg) + msg_size;
1652 	msg = malloc(len, M_MQUEUEDATA, M_WAITOK);
1653 	error = copyin(msg_ptr, ((char *)msg) + sizeof(struct mqueue_msg),
1654 	    msg_size);
1655 	if (error) {
1656 		free(msg, M_MQUEUEDATA);
1657 		msg = NULL;
1658 	} else {
1659 		msg->msg_size = msg_size;
1660 		msg->msg_prio = msg_prio;
1661 	}
1662 	return (msg);
1663 }
1664 
1665 /*
1666  * Save a message to user space
1667  */
1668 static int
1669 mqueue_savemsg(struct mqueue_msg *msg, char *msg_ptr, int *msg_prio)
1670 {
1671 	int error;
1672 
1673 	error = copyout(((char *)msg) + sizeof(*msg), msg_ptr,
1674 		msg->msg_size);
1675 	if (error == 0 && msg_prio != NULL)
1676 		error = copyout(&msg->msg_prio, msg_prio, sizeof(int));
1677 	return (error);
1678 }
1679 
1680 /*
1681  * Free a message's memory
1682  */
1683 static __inline void
1684 mqueue_freemsg(struct mqueue_msg *msg)
1685 {
1686 	free(msg, M_MQUEUEDATA);
1687 }
1688 
1689 /*
1690  * Send a message. if waitok is false, thread will not be
1691  * blocked if there is no data in queue, otherwise, absolute
1692  * time will be checked.
1693  */
1694 int
1695 mqueue_send(struct mqueue *mq, const char *msg_ptr,
1696 	size_t msg_len, unsigned msg_prio, int waitok,
1697 	const struct timespec *abs_timeout)
1698 {
1699 	struct mqueue_msg *msg;
1700 	struct timespec ts, ts2;
1701 	struct timeval tv;
1702 	int error;
1703 
1704 	if (msg_prio >= MQ_PRIO_MAX)
1705 		return (EINVAL);
1706 	if (msg_len > mq->mq_msgsize)
1707 		return (EMSGSIZE);
1708 	msg = mqueue_loadmsg(msg_ptr, msg_len, msg_prio);
1709 	if (msg == NULL)
1710 		return (EFAULT);
1711 
1712 	/* O_NONBLOCK case */
1713 	if (!waitok) {
1714 		error = _mqueue_send(mq, msg, -1);
1715 		if (error)
1716 			goto bad;
1717 		return (0);
1718 	}
1719 
1720 	/* we allow a null timeout (wait forever) */
1721 	if (abs_timeout == NULL) {
1722 		error = _mqueue_send(mq, msg, 0);
1723 		if (error)
1724 			goto bad;
1725 		return (0);
1726 	}
1727 
1728 	/* send it before checking time */
1729 	error = _mqueue_send(mq, msg, -1);
1730 	if (error == 0)
1731 		return (0);
1732 
1733 	if (error != EAGAIN)
1734 		goto bad;
1735 
1736 	if (abs_timeout->tv_nsec >= 1000000000 || abs_timeout->tv_nsec < 0) {
1737 		error = EINVAL;
1738 		goto bad;
1739 	}
1740 	for (;;) {
1741 		ts2 = *abs_timeout;
1742 		getnanotime(&ts);
1743 		timespecsub(&ts2, &ts);
1744 		if (ts2.tv_sec < 0 || (ts2.tv_sec == 0 && ts2.tv_nsec <= 0)) {
1745 			error = ETIMEDOUT;
1746 			break;
1747 		}
1748 		TIMESPEC_TO_TIMEVAL(&tv, &ts2);
1749 		error = _mqueue_send(mq, msg, tvtohz(&tv));
1750 		if (error != ETIMEDOUT)
1751 			break;
1752 	}
1753 	if (error == 0)
1754 		return (0);
1755 bad:
1756 	mqueue_freemsg(msg);
1757 	return (error);
1758 }
1759 
1760 /*
1761  * Common routine to send a message
1762  */
1763 static int
1764 _mqueue_send(struct mqueue *mq, struct mqueue_msg *msg, int timo)
1765 {
1766 	struct mqueue_msg *msg2;
1767 	int error = 0;
1768 
1769 	mtx_lock(&mq->mq_mutex);
1770 	while (mq->mq_curmsgs >= mq->mq_maxmsg && error == 0) {
1771 		if (timo < 0) {
1772 			mtx_unlock(&mq->mq_mutex);
1773 			return (EAGAIN);
1774 		}
1775 		mq->mq_senders++;
1776 		error = msleep(&mq->mq_senders, &mq->mq_mutex,
1777 			    PCATCH, "mqsend", timo);
1778 		mq->mq_senders--;
1779 		if (error == EAGAIN)
1780 			error = ETIMEDOUT;
1781 	}
1782 	if (mq->mq_curmsgs >= mq->mq_maxmsg) {
1783 		mtx_unlock(&mq->mq_mutex);
1784 		return (error);
1785 	}
1786 	error = 0;
1787 	if (TAILQ_EMPTY(&mq->mq_msgq)) {
1788 		TAILQ_INSERT_HEAD(&mq->mq_msgq, msg, msg_link);
1789 	} else {
1790 		if (msg->msg_prio <= TAILQ_LAST(&mq->mq_msgq, msgq)->msg_prio) {
1791 			TAILQ_INSERT_TAIL(&mq->mq_msgq, msg, msg_link);
1792 		} else {
1793 			TAILQ_FOREACH(msg2, &mq->mq_msgq, msg_link) {
1794 				if (msg2->msg_prio < msg->msg_prio)
1795 					break;
1796 			}
1797 			TAILQ_INSERT_BEFORE(msg2, msg, msg_link);
1798 		}
1799 	}
1800 	mq->mq_curmsgs++;
1801 	mq->mq_totalbytes += msg->msg_size;
1802 	if (mq->mq_receivers)
1803 		wakeup_one(&mq->mq_receivers);
1804 	else if (mq->mq_notifier != NULL)
1805 		mqueue_send_notification(mq);
1806 	if (mq->mq_flags & MQ_RSEL) {
1807 		mq->mq_flags &= ~MQ_RSEL;
1808 		selwakeup(&mq->mq_rsel);
1809 	}
1810 	KNOTE_LOCKED(&mq->mq_rsel.si_note, 0);
1811 	mtx_unlock(&mq->mq_mutex);
1812 	return (0);
1813 }
1814 
1815 /*
1816  * Send realtime a signal to process which registered itself
1817  * successfully by mq_notify.
1818  */
1819 static void
1820 mqueue_send_notification(struct mqueue *mq)
1821 {
1822 	struct mqueue_notifier *nt;
1823 	struct thread *td;
1824 	struct proc *p;
1825 	int error;
1826 
1827 	mtx_assert(&mq->mq_mutex, MA_OWNED);
1828 	nt = mq->mq_notifier;
1829 	if (nt->nt_sigev.sigev_notify != SIGEV_NONE) {
1830 		p = nt->nt_proc;
1831 		error = sigev_findtd(p, &nt->nt_sigev, &td);
1832 		if (error) {
1833 			mq->mq_notifier = NULL;
1834 			return;
1835 		}
1836 		if (!KSI_ONQ(&nt->nt_ksi)) {
1837 			ksiginfo_set_sigev(&nt->nt_ksi, &nt->nt_sigev);
1838 			tdsendsignal(p, td, nt->nt_ksi.ksi_signo, &nt->nt_ksi);
1839 		}
1840 		PROC_UNLOCK(p);
1841 	}
1842 	mq->mq_notifier = NULL;
1843 }
1844 
1845 /*
1846  * Get a message. if waitok is false, thread will not be
1847  * blocked if there is no data in queue, otherwise, absolute
1848  * time will be checked.
1849  */
1850 int
1851 mqueue_receive(struct mqueue *mq, char *msg_ptr,
1852 	size_t msg_len, unsigned *msg_prio, int waitok,
1853 	const struct timespec *abs_timeout)
1854 {
1855 	struct mqueue_msg *msg;
1856 	struct timespec ts, ts2;
1857 	struct timeval tv;
1858 	int error;
1859 
1860 	if (msg_len < mq->mq_msgsize)
1861 		return (EMSGSIZE);
1862 
1863 	/* O_NONBLOCK case */
1864 	if (!waitok) {
1865 		error = _mqueue_recv(mq, &msg, -1);
1866 		if (error)
1867 			return (error);
1868 		goto received;
1869 	}
1870 
1871 	/* we allow a null timeout (wait forever). */
1872 	if (abs_timeout == NULL) {
1873 		error = _mqueue_recv(mq, &msg, 0);
1874 		if (error)
1875 			return (error);
1876 		goto received;
1877 	}
1878 
1879 	/* try to get a message before checking time */
1880 	error = _mqueue_recv(mq, &msg, -1);
1881 	if (error == 0)
1882 		goto received;
1883 
1884 	if (error != EAGAIN)
1885 		return (error);
1886 
1887 	if (abs_timeout->tv_nsec >= 1000000000 || abs_timeout->tv_nsec < 0) {
1888 		error = EINVAL;
1889 		return (error);
1890 	}
1891 
1892 	for (;;) {
1893 		ts2 = *abs_timeout;
1894 		getnanotime(&ts);
1895 		timespecsub(&ts2, &ts);
1896 		if (ts2.tv_sec < 0 || (ts2.tv_sec == 0 && ts2.tv_nsec <= 0)) {
1897 			error = ETIMEDOUT;
1898 			return (error);
1899 		}
1900 		TIMESPEC_TO_TIMEVAL(&tv, &ts2);
1901 		error = _mqueue_recv(mq, &msg, tvtohz(&tv));
1902 		if (error == 0)
1903 			break;
1904 		if (error != ETIMEDOUT)
1905 			return (error);
1906 	}
1907 
1908 received:
1909 	error = mqueue_savemsg(msg, msg_ptr, msg_prio);
1910 	if (error == 0) {
1911 		curthread->td_retval[0] = msg->msg_size;
1912 		curthread->td_retval[1] = 0;
1913 	}
1914 	mqueue_freemsg(msg);
1915 	return (error);
1916 }
1917 
1918 /*
1919  * Common routine to receive a message
1920  */
1921 static int
1922 _mqueue_recv(struct mqueue *mq, struct mqueue_msg **msg, int timo)
1923 {
1924 	int error = 0;
1925 
1926 	mtx_lock(&mq->mq_mutex);
1927 	while ((*msg = TAILQ_FIRST(&mq->mq_msgq)) == NULL && error == 0) {
1928 		if (timo < 0) {
1929 			mtx_unlock(&mq->mq_mutex);
1930 			return (EAGAIN);
1931 		}
1932 		mq->mq_receivers++;
1933 		error = msleep(&mq->mq_receivers, &mq->mq_mutex,
1934 			    PCATCH, "mqrecv", timo);
1935 		mq->mq_receivers--;
1936 		if (error == EAGAIN)
1937 			error = ETIMEDOUT;
1938 	}
1939 	if (*msg != NULL) {
1940 		error = 0;
1941 		TAILQ_REMOVE(&mq->mq_msgq, *msg, msg_link);
1942 		mq->mq_curmsgs--;
1943 		mq->mq_totalbytes -= (*msg)->msg_size;
1944 		if (mq->mq_senders)
1945 			wakeup_one(&mq->mq_senders);
1946 		if (mq->mq_flags & MQ_WSEL) {
1947 			mq->mq_flags &= ~MQ_WSEL;
1948 			selwakeup(&mq->mq_wsel);
1949 		}
1950 		KNOTE_LOCKED(&mq->mq_wsel.si_note, 0);
1951 	}
1952 	if (mq->mq_notifier != NULL && mq->mq_receivers == 0 &&
1953 	    !TAILQ_EMPTY(&mq->mq_msgq)) {
1954 		mqueue_send_notification(mq);
1955 	}
1956 	mtx_unlock(&mq->mq_mutex);
1957 	return (error);
1958 }
1959 
1960 static __inline struct mqueue_notifier *
1961 notifier_alloc(void)
1962 {
1963 	return (uma_zalloc(mqnoti_zone, M_WAITOK | M_ZERO));
1964 }
1965 
1966 static __inline void
1967 notifier_free(struct mqueue_notifier *p)
1968 {
1969 	uma_zfree(mqnoti_zone, p);
1970 }
1971 
1972 static struct mqueue_notifier *
1973 notifier_search(struct proc *p, int fd)
1974 {
1975 	struct mqueue_notifier *nt;
1976 
1977 	LIST_FOREACH(nt, &p->p_mqnotifier, nt_link) {
1978 		if (nt->nt_ksi.ksi_mqd == fd)
1979 			break;
1980 	}
1981 	return (nt);
1982 }
1983 
1984 static __inline void
1985 notifier_insert(struct proc *p, struct mqueue_notifier *nt)
1986 {
1987 	LIST_INSERT_HEAD(&p->p_mqnotifier, nt, nt_link);
1988 }
1989 
1990 static __inline void
1991 notifier_delete(struct proc *p, struct mqueue_notifier *nt)
1992 {
1993 	LIST_REMOVE(nt, nt_link);
1994 	notifier_free(nt);
1995 }
1996 
1997 static void
1998 notifier_remove(struct proc *p, struct mqueue *mq, int fd)
1999 {
2000 	struct mqueue_notifier *nt;
2001 
2002 	mtx_assert(&mq->mq_mutex, MA_OWNED);
2003 	PROC_LOCK(p);
2004 	nt = notifier_search(p, fd);
2005 	if (nt != NULL) {
2006 		if (mq->mq_notifier == nt)
2007 			mq->mq_notifier = NULL;
2008 		sigqueue_take(&nt->nt_ksi);
2009 		notifier_delete(p, nt);
2010 	}
2011 	PROC_UNLOCK(p);
2012 }
2013 
2014 static int
2015 kern_kmq_open(struct thread *td, const char *upath, int flags, mode_t mode,
2016     const struct mq_attr *attr)
2017 {
2018 	char path[MQFS_NAMELEN + 1];
2019 	struct mqfs_node *pn;
2020 	struct filedesc *fdp;
2021 	struct file *fp;
2022 	struct mqueue *mq;
2023 	int fd, error, len, cmode;
2024 
2025 	AUDIT_ARG_FFLAGS(flags);
2026 	AUDIT_ARG_MODE(mode);
2027 
2028 	fdp = td->td_proc->p_fd;
2029 	cmode = (((mode & ~fdp->fd_cmask) & ALLPERMS) & ~S_ISTXT);
2030 	mq = NULL;
2031 	if ((flags & O_CREAT) != 0 && attr != NULL) {
2032 		if (attr->mq_maxmsg <= 0 || attr->mq_maxmsg > maxmsg)
2033 			return (EINVAL);
2034 		if (attr->mq_msgsize <= 0 || attr->mq_msgsize > maxmsgsize)
2035 			return (EINVAL);
2036 	}
2037 
2038 	error = copyinstr(upath, path, MQFS_NAMELEN + 1, NULL);
2039         if (error)
2040 		return (error);
2041 
2042 	/*
2043 	 * The first character of name must be a slash  (/) character
2044 	 * and the remaining characters of name cannot include any slash
2045 	 * characters.
2046 	 */
2047 	len = strlen(path);
2048 	if (len < 2 || path[0] != '/' || strchr(path + 1, '/') != NULL)
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, NULL);
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 	AUDIT_ARG_UPATH1_CANON(path);
2151 
2152 	sx_xlock(&mqfs_data.mi_lock);
2153 	pn = mqfs_search(mqfs_data.mi_root, path + 1, len - 1, td->td_ucred);
2154 	if (pn != NULL)
2155 		error = do_unlink(pn, td->td_ucred);
2156 	else
2157 		error = ENOENT;
2158 	sx_xunlock(&mqfs_data.mi_lock);
2159 	return (error);
2160 }
2161 
2162 typedef int (*_fgetf)(struct thread *, int, cap_rights_t *, struct file **);
2163 
2164 /*
2165  * Get message queue by giving file slot
2166  */
2167 static int
2168 _getmq(struct thread *td, int fd, cap_rights_t *rightsp, _fgetf func,
2169        struct file **fpp, struct mqfs_node **ppn, struct mqueue **pmq)
2170 {
2171 	struct mqfs_node *pn;
2172 	int error;
2173 
2174 	error = func(td, fd, rightsp, fpp);
2175 	if (error)
2176 		return (error);
2177 	if (&mqueueops != (*fpp)->f_ops) {
2178 		fdrop(*fpp, td);
2179 		return (EBADF);
2180 	}
2181 	pn = (*fpp)->f_data;
2182 	if (ppn)
2183 		*ppn = pn;
2184 	if (pmq)
2185 		*pmq = pn->mn_data;
2186 	return (0);
2187 }
2188 
2189 static __inline int
2190 getmq(struct thread *td, int fd, struct file **fpp, struct mqfs_node **ppn,
2191 	struct mqueue **pmq)
2192 {
2193 	cap_rights_t rights;
2194 
2195 	return _getmq(td, fd, cap_rights_init(&rights, CAP_EVENT), fget,
2196 	    fpp, ppn, pmq);
2197 }
2198 
2199 static __inline int
2200 getmq_read(struct thread *td, int fd, struct file **fpp,
2201 	 struct mqfs_node **ppn, struct mqueue **pmq)
2202 {
2203 	cap_rights_t rights;
2204 
2205 	return _getmq(td, fd, cap_rights_init(&rights, CAP_READ), 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 	cap_rights_t rights;
2214 
2215 	return _getmq(td, fd, cap_rights_init(&rights, CAP_WRITE), fget_write,
2216 	    fpp, ppn, pmq);
2217 }
2218 
2219 static int
2220 kern_kmq_setattr(struct thread *td, int mqd, const struct mq_attr *attr,
2221     struct mq_attr *oattr)
2222 {
2223 	struct mqueue *mq;
2224 	struct file *fp;
2225 	u_int oflag, flag;
2226 	int error;
2227 
2228 	AUDIT_ARG_FD(mqd);
2229 	if (attr != NULL && (attr->mq_flags & ~O_NONBLOCK) != 0)
2230 		return (EINVAL);
2231 	error = getmq(td, mqd, &fp, NULL, &mq);
2232 	if (error)
2233 		return (error);
2234 	oattr->mq_maxmsg  = mq->mq_maxmsg;
2235 	oattr->mq_msgsize = mq->mq_msgsize;
2236 	oattr->mq_curmsgs = mq->mq_curmsgs;
2237 	if (attr != NULL) {
2238 		do {
2239 			oflag = flag = fp->f_flag;
2240 			flag &= ~O_NONBLOCK;
2241 			flag |= (attr->mq_flags & O_NONBLOCK);
2242 		} while (atomic_cmpset_int(&fp->f_flag, oflag, flag) == 0);
2243 	} else
2244 		oflag = fp->f_flag;
2245 	oattr->mq_flags = (O_NONBLOCK & oflag);
2246 	fdrop(fp, td);
2247 	return (error);
2248 }
2249 
2250 int
2251 sys_kmq_setattr(struct thread *td, struct kmq_setattr_args *uap)
2252 {
2253 	struct mq_attr attr, oattr;
2254 	int error;
2255 
2256 	if (uap->attr != NULL) {
2257 		error = copyin(uap->attr, &attr, sizeof(attr));
2258 		if (error != 0)
2259 			return (error);
2260 	}
2261 	error = kern_kmq_setattr(td, uap->mqd, uap->attr != NULL ? &attr : NULL,
2262 	    &oattr);
2263 	if (error == 0 && uap->oattr != NULL) {
2264 		bzero(oattr.__reserved, sizeof(oattr.__reserved));
2265 		error = copyout(&oattr, uap->oattr, sizeof(oattr));
2266 	}
2267 	return (error);
2268 }
2269 
2270 int
2271 sys_kmq_timedreceive(struct thread *td, struct kmq_timedreceive_args *uap)
2272 {
2273 	struct mqueue *mq;
2274 	struct file *fp;
2275 	struct timespec *abs_timeout, ets;
2276 	int error;
2277 	int waitok;
2278 
2279 	AUDIT_ARG_FD(uap->mqd);
2280 	error = getmq_read(td, uap->mqd, &fp, NULL, &mq);
2281 	if (error)
2282 		return (error);
2283 	if (uap->abs_timeout != NULL) {
2284 		error = copyin(uap->abs_timeout, &ets, sizeof(ets));
2285 		if (error != 0)
2286 			return (error);
2287 		abs_timeout = &ets;
2288 	} else
2289 		abs_timeout = NULL;
2290 	waitok = !(fp->f_flag & O_NONBLOCK);
2291 	error = mqueue_receive(mq, uap->msg_ptr, uap->msg_len,
2292 		uap->msg_prio, waitok, abs_timeout);
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 			return (error);
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 	fdrop(fp, td);
2320 	return (error);
2321 }
2322 
2323 static int
2324 kern_kmq_notify(struct thread *td, int mqd, struct sigevent *sigev)
2325 {
2326 #ifdef CAPABILITIES
2327 	cap_rights_t rights;
2328 #endif
2329 	struct filedesc *fdp;
2330 	struct proc *p;
2331 	struct mqueue *mq;
2332 	struct file *fp, *fp2;
2333 	struct mqueue_notifier *nt, *newnt = NULL;
2334 	int error;
2335 
2336 	AUDIT_ARG_FD(mqd);
2337 	if (sigev != NULL) {
2338 		if (sigev->sigev_notify != SIGEV_SIGNAL &&
2339 		    sigev->sigev_notify != SIGEV_THREAD_ID &&
2340 		    sigev->sigev_notify != SIGEV_NONE)
2341 			return (EINVAL);
2342 		if ((sigev->sigev_notify == SIGEV_SIGNAL ||
2343 		    sigev->sigev_notify == SIGEV_THREAD_ID) &&
2344 		    !_SIG_VALID(sigev->sigev_signo))
2345 			return (EINVAL);
2346 	}
2347 	p = td->td_proc;
2348 	fdp = td->td_proc->p_fd;
2349 	error = getmq(td, mqd, &fp, NULL, &mq);
2350 	if (error)
2351 		return (error);
2352 again:
2353 	FILEDESC_SLOCK(fdp);
2354 	fp2 = fget_locked(fdp, mqd);
2355 	if (fp2 == NULL) {
2356 		FILEDESC_SUNLOCK(fdp);
2357 		error = EBADF;
2358 		goto out;
2359 	}
2360 #ifdef CAPABILITIES
2361 	error = cap_check(cap_rights(fdp, mqd),
2362 	    cap_rights_init(&rights, CAP_EVENT));
2363 	if (error) {
2364 		FILEDESC_SUNLOCK(fdp);
2365 		goto out;
2366 	}
2367 #endif
2368 	if (fp2 != fp) {
2369 		FILEDESC_SUNLOCK(fdp);
2370 		error = EBADF;
2371 		goto out;
2372 	}
2373 	mtx_lock(&mq->mq_mutex);
2374 	FILEDESC_SUNLOCK(fdp);
2375 	if (sigev != NULL) {
2376 		if (mq->mq_notifier != NULL) {
2377 			error = EBUSY;
2378 		} else {
2379 			PROC_LOCK(p);
2380 			nt = notifier_search(p, mqd);
2381 			if (nt == NULL) {
2382 				if (newnt == NULL) {
2383 					PROC_UNLOCK(p);
2384 					mtx_unlock(&mq->mq_mutex);
2385 					newnt = notifier_alloc();
2386 					goto again;
2387 				}
2388 			}
2389 
2390 			if (nt != NULL) {
2391 				sigqueue_take(&nt->nt_ksi);
2392 				if (newnt != NULL) {
2393 					notifier_free(newnt);
2394 					newnt = NULL;
2395 				}
2396 			} else {
2397 				nt = newnt;
2398 				newnt = NULL;
2399 				ksiginfo_init(&nt->nt_ksi);
2400 				nt->nt_ksi.ksi_flags |= KSI_INS | KSI_EXT;
2401 				nt->nt_ksi.ksi_code = SI_MESGQ;
2402 				nt->nt_proc = p;
2403 				nt->nt_ksi.ksi_mqd = mqd;
2404 				notifier_insert(p, nt);
2405 			}
2406 			nt->nt_sigev = *sigev;
2407 			mq->mq_notifier = nt;
2408 			PROC_UNLOCK(p);
2409 			/*
2410 			 * if there is no receivers and message queue
2411 			 * is not empty, we should send notification
2412 			 * as soon as possible.
2413 			 */
2414 			if (mq->mq_receivers == 0 &&
2415 			    !TAILQ_EMPTY(&mq->mq_msgq))
2416 				mqueue_send_notification(mq);
2417 		}
2418 	} else {
2419 		notifier_remove(p, mq, mqd);
2420 	}
2421 	mtx_unlock(&mq->mq_mutex);
2422 
2423 out:
2424 	fdrop(fp, td);
2425 	if (newnt != NULL)
2426 		notifier_free(newnt);
2427 	return (error);
2428 }
2429 
2430 int
2431 sys_kmq_notify(struct thread *td, struct kmq_notify_args *uap)
2432 {
2433 	struct sigevent ev, *evp;
2434 	int error;
2435 
2436 	if (uap->sigev == NULL) {
2437 		evp = NULL;
2438 	} else {
2439 		error = copyin(uap->sigev, &ev, sizeof(ev));
2440 		if (error != 0)
2441 			return (error);
2442 		evp = &ev;
2443 	}
2444 	return (kern_kmq_notify(td, uap->mqd, evp));
2445 }
2446 
2447 static void
2448 mqueue_fdclose(struct thread *td, int fd, struct file *fp)
2449 {
2450 	struct filedesc *fdp;
2451 	struct mqueue *mq;
2452 
2453 	fdp = td->td_proc->p_fd;
2454 	FILEDESC_LOCK_ASSERT(fdp);
2455 
2456 	if (fp->f_ops == &mqueueops) {
2457 		mq = FPTOMQ(fp);
2458 		mtx_lock(&mq->mq_mutex);
2459 		notifier_remove(td->td_proc, mq, fd);
2460 
2461 		/* have to wakeup thread in same process */
2462 		if (mq->mq_flags & MQ_RSEL) {
2463 			mq->mq_flags &= ~MQ_RSEL;
2464 			selwakeup(&mq->mq_rsel);
2465 		}
2466 		if (mq->mq_flags & MQ_WSEL) {
2467 			mq->mq_flags &= ~MQ_WSEL;
2468 			selwakeup(&mq->mq_wsel);
2469 		}
2470 		mtx_unlock(&mq->mq_mutex);
2471 	}
2472 }
2473 
2474 static void
2475 mq_proc_exit(void *arg __unused, struct proc *p)
2476 {
2477 	struct filedesc *fdp;
2478 	struct file *fp;
2479 	struct mqueue *mq;
2480 	int i;
2481 
2482 	fdp = p->p_fd;
2483 	FILEDESC_SLOCK(fdp);
2484 	for (i = 0; i < fdp->fd_nfiles; ++i) {
2485 		fp = fget_locked(fdp, i);
2486 		if (fp != NULL && fp->f_ops == &mqueueops) {
2487 			mq = FPTOMQ(fp);
2488 			mtx_lock(&mq->mq_mutex);
2489 			notifier_remove(p, FPTOMQ(fp), i);
2490 			mtx_unlock(&mq->mq_mutex);
2491 		}
2492 	}
2493 	FILEDESC_SUNLOCK(fdp);
2494 	KASSERT(LIST_EMPTY(&p->p_mqnotifier), ("mq notifiers left"));
2495 }
2496 
2497 static int
2498 mqf_poll(struct file *fp, int events, struct ucred *active_cred,
2499 	struct thread *td)
2500 {
2501 	struct mqueue *mq = FPTOMQ(fp);
2502 	int revents = 0;
2503 
2504 	mtx_lock(&mq->mq_mutex);
2505 	if (events & (POLLIN | POLLRDNORM)) {
2506 		if (mq->mq_curmsgs) {
2507 			revents |= events & (POLLIN | POLLRDNORM);
2508 		} else {
2509 			mq->mq_flags |= MQ_RSEL;
2510 			selrecord(td, &mq->mq_rsel);
2511  		}
2512 	}
2513 	if (events & POLLOUT) {
2514 		if (mq->mq_curmsgs < mq->mq_maxmsg)
2515 			revents |= POLLOUT;
2516 		else {
2517 			mq->mq_flags |= MQ_WSEL;
2518 			selrecord(td, &mq->mq_wsel);
2519 		}
2520 	}
2521 	mtx_unlock(&mq->mq_mutex);
2522 	return (revents);
2523 }
2524 
2525 static int
2526 mqf_close(struct file *fp, struct thread *td)
2527 {
2528 	struct mqfs_node *pn;
2529 
2530 	fp->f_ops = &badfileops;
2531 	pn = fp->f_data;
2532 	fp->f_data = NULL;
2533 	sx_xlock(&mqfs_data.mi_lock);
2534 	mqnode_release(pn);
2535 	sx_xunlock(&mqfs_data.mi_lock);
2536 	return (0);
2537 }
2538 
2539 static int
2540 mqf_stat(struct file *fp, struct stat *st, struct ucred *active_cred,
2541 	struct thread *td)
2542 {
2543 	struct mqfs_node *pn = fp->f_data;
2544 
2545 	bzero(st, sizeof *st);
2546 	sx_xlock(&mqfs_data.mi_lock);
2547 	st->st_atim = pn->mn_atime;
2548 	st->st_mtim = pn->mn_mtime;
2549 	st->st_ctim = pn->mn_ctime;
2550 	st->st_birthtim = pn->mn_birth;
2551 	st->st_uid = pn->mn_uid;
2552 	st->st_gid = pn->mn_gid;
2553 	st->st_mode = S_IFIFO | pn->mn_mode;
2554 	sx_xunlock(&mqfs_data.mi_lock);
2555 	return (0);
2556 }
2557 
2558 static int
2559 mqf_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
2560     struct thread *td)
2561 {
2562 	struct mqfs_node *pn;
2563 	int error;
2564 
2565 	error = 0;
2566 	pn = fp->f_data;
2567 	sx_xlock(&mqfs_data.mi_lock);
2568 	error = vaccess(VREG, pn->mn_mode, pn->mn_uid, pn->mn_gid, VADMIN,
2569 	    active_cred, NULL);
2570 	if (error != 0)
2571 		goto out;
2572 	pn->mn_mode = mode & ACCESSPERMS;
2573 out:
2574 	sx_xunlock(&mqfs_data.mi_lock);
2575 	return (error);
2576 }
2577 
2578 static int
2579 mqf_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
2580     struct thread *td)
2581 {
2582 	struct mqfs_node *pn;
2583 	int error;
2584 
2585 	error = 0;
2586 	pn = fp->f_data;
2587 	sx_xlock(&mqfs_data.mi_lock);
2588 	if (uid == (uid_t)-1)
2589 		uid = pn->mn_uid;
2590 	if (gid == (gid_t)-1)
2591 		gid = pn->mn_gid;
2592 	if (((uid != pn->mn_uid && uid != active_cred->cr_uid) ||
2593 	    (gid != pn->mn_gid && !groupmember(gid, active_cred))) &&
2594 	    (error = priv_check_cred(active_cred, PRIV_VFS_CHOWN, 0)))
2595 		goto out;
2596 	pn->mn_uid = uid;
2597 	pn->mn_gid = gid;
2598 out:
2599 	sx_xunlock(&mqfs_data.mi_lock);
2600 	return (error);
2601 }
2602 
2603 static int
2604 mqf_kqfilter(struct file *fp, struct knote *kn)
2605 {
2606 	struct mqueue *mq = FPTOMQ(fp);
2607 	int error = 0;
2608 
2609 	if (kn->kn_filter == EVFILT_READ) {
2610 		kn->kn_fop = &mq_rfiltops;
2611 		knlist_add(&mq->mq_rsel.si_note, kn, 0);
2612 	} else if (kn->kn_filter == EVFILT_WRITE) {
2613 		kn->kn_fop = &mq_wfiltops;
2614 		knlist_add(&mq->mq_wsel.si_note, kn, 0);
2615 	} else
2616 		error = EINVAL;
2617 	return (error);
2618 }
2619 
2620 static void
2621 filt_mqdetach(struct knote *kn)
2622 {
2623 	struct mqueue *mq = FPTOMQ(kn->kn_fp);
2624 
2625 	if (kn->kn_filter == EVFILT_READ)
2626 		knlist_remove(&mq->mq_rsel.si_note, kn, 0);
2627 	else if (kn->kn_filter == EVFILT_WRITE)
2628 		knlist_remove(&mq->mq_wsel.si_note, kn, 0);
2629 	else
2630 		panic("filt_mqdetach");
2631 }
2632 
2633 static int
2634 filt_mqread(struct knote *kn, long hint)
2635 {
2636 	struct mqueue *mq = FPTOMQ(kn->kn_fp);
2637 
2638 	mtx_assert(&mq->mq_mutex, MA_OWNED);
2639 	return (mq->mq_curmsgs != 0);
2640 }
2641 
2642 static int
2643 filt_mqwrite(struct knote *kn, long hint)
2644 {
2645 	struct mqueue *mq = FPTOMQ(kn->kn_fp);
2646 
2647 	mtx_assert(&mq->mq_mutex, MA_OWNED);
2648 	return (mq->mq_curmsgs < mq->mq_maxmsg);
2649 }
2650 
2651 static int
2652 mqf_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
2653 {
2654 
2655 	kif->kf_type = KF_TYPE_MQUEUE;
2656 	return (0);
2657 }
2658 
2659 static struct fileops mqueueops = {
2660 	.fo_read		= invfo_rdwr,
2661 	.fo_write		= invfo_rdwr,
2662 	.fo_truncate		= invfo_truncate,
2663 	.fo_ioctl		= invfo_ioctl,
2664 	.fo_poll		= mqf_poll,
2665 	.fo_kqfilter		= mqf_kqfilter,
2666 	.fo_stat		= mqf_stat,
2667 	.fo_close		= mqf_close,
2668 	.fo_chmod		= mqf_chmod,
2669 	.fo_chown		= mqf_chown,
2670 	.fo_sendfile		= invfo_sendfile,
2671 	.fo_fill_kinfo		= mqf_fill_kinfo,
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 
2694 static struct vfsops mqfs_vfsops = {
2695 	.vfs_init 		= mqfs_init,
2696 	.vfs_uninit		= mqfs_uninit,
2697 	.vfs_mount		= mqfs_mount,
2698 	.vfs_unmount		= mqfs_unmount,
2699 	.vfs_root		= mqfs_root,
2700 	.vfs_statfs		= mqfs_statfs,
2701 };
2702 
2703 static struct vfsconf mqueuefs_vfsconf = {
2704 	.vfc_version = VFS_VERSION,
2705 	.vfc_name = "mqueuefs",
2706 	.vfc_vfsops = &mqfs_vfsops,
2707 	.vfc_typenum = -1,
2708 	.vfc_flags = VFCF_SYNTHETIC
2709 };
2710 
2711 static struct syscall_helper_data mq_syscalls[] = {
2712 	SYSCALL_INIT_HELPER(kmq_open),
2713 	SYSCALL_INIT_HELPER_F(kmq_setattr, SYF_CAPENABLED),
2714 	SYSCALL_INIT_HELPER_F(kmq_timedsend, SYF_CAPENABLED),
2715 	SYSCALL_INIT_HELPER_F(kmq_timedreceive, SYF_CAPENABLED),
2716 	SYSCALL_INIT_HELPER_F(kmq_notify, SYF_CAPENABLED),
2717 	SYSCALL_INIT_HELPER(kmq_unlink),
2718 	SYSCALL_INIT_LAST
2719 };
2720 
2721 #ifdef COMPAT_FREEBSD32
2722 #include <compat/freebsd32/freebsd32.h>
2723 #include <compat/freebsd32/freebsd32_proto.h>
2724 #include <compat/freebsd32/freebsd32_signal.h>
2725 #include <compat/freebsd32/freebsd32_syscall.h>
2726 #include <compat/freebsd32/freebsd32_util.h>
2727 
2728 static void
2729 mq_attr_from32(const struct mq_attr32 *from, struct mq_attr *to)
2730 {
2731 
2732 	to->mq_flags = from->mq_flags;
2733 	to->mq_maxmsg = from->mq_maxmsg;
2734 	to->mq_msgsize = from->mq_msgsize;
2735 	to->mq_curmsgs = from->mq_curmsgs;
2736 }
2737 
2738 static void
2739 mq_attr_to32(const struct mq_attr *from, struct mq_attr32 *to)
2740 {
2741 
2742 	to->mq_flags = from->mq_flags;
2743 	to->mq_maxmsg = from->mq_maxmsg;
2744 	to->mq_msgsize = from->mq_msgsize;
2745 	to->mq_curmsgs = from->mq_curmsgs;
2746 }
2747 
2748 int
2749 freebsd32_kmq_open(struct thread *td, struct freebsd32_kmq_open_args *uap)
2750 {
2751 	struct mq_attr attr;
2752 	struct mq_attr32 attr32;
2753 	int flags, error;
2754 
2755 	if ((uap->flags & O_ACCMODE) == O_ACCMODE || uap->flags & O_EXEC)
2756 		return (EINVAL);
2757 	flags = FFLAGS(uap->flags);
2758 	if ((flags & O_CREAT) != 0 && uap->attr != NULL) {
2759 		error = copyin(uap->attr, &attr32, sizeof(attr32));
2760 		if (error)
2761 			return (error);
2762 		mq_attr_from32(&attr32, &attr);
2763 	}
2764 	return (kern_kmq_open(td, uap->path, flags, uap->mode,
2765 	    uap->attr != NULL ? &attr : NULL));
2766 }
2767 
2768 int
2769 freebsd32_kmq_setattr(struct thread *td, struct freebsd32_kmq_setattr_args *uap)
2770 {
2771 	struct mq_attr attr, oattr;
2772 	struct mq_attr32 attr32, oattr32;
2773 	int error;
2774 
2775 	if (uap->attr != NULL) {
2776 		error = copyin(uap->attr, &attr32, sizeof(attr32));
2777 		if (error != 0)
2778 			return (error);
2779 		mq_attr_from32(&attr32, &attr);
2780 	}
2781 	error = kern_kmq_setattr(td, uap->mqd, uap->attr != NULL ? &attr : NULL,
2782 	    &oattr);
2783 	if (error == 0 && uap->oattr != NULL) {
2784 		mq_attr_to32(&oattr, &oattr32);
2785 		bzero(oattr32.__reserved, sizeof(oattr32.__reserved));
2786 		error = copyout(&oattr32, uap->oattr, sizeof(oattr32));
2787 	}
2788 	return (error);
2789 }
2790 
2791 int
2792 freebsd32_kmq_timedsend(struct thread *td,
2793     struct freebsd32_kmq_timedsend_args *uap)
2794 {
2795 	struct mqueue *mq;
2796 	struct file *fp;
2797 	struct timespec32 ets32;
2798 	struct timespec *abs_timeout, ets;
2799 	int error;
2800 	int waitok;
2801 
2802 	AUDIT_ARG_FD(uap->mqd);
2803 	error = getmq_write(td, uap->mqd, &fp, NULL, &mq);
2804 	if (error)
2805 		return (error);
2806 	if (uap->abs_timeout != NULL) {
2807 		error = copyin(uap->abs_timeout, &ets32, sizeof(ets32));
2808 		if (error != 0)
2809 			return (error);
2810 		CP(ets32, ets, tv_sec);
2811 		CP(ets32, ets, tv_nsec);
2812 		abs_timeout = &ets;
2813 	} else
2814 		abs_timeout = NULL;
2815 	waitok = !(fp->f_flag & O_NONBLOCK);
2816 	error = mqueue_send(mq, uap->msg_ptr, uap->msg_len,
2817 		uap->msg_prio, waitok, abs_timeout);
2818 	fdrop(fp, td);
2819 	return (error);
2820 }
2821 
2822 int
2823 freebsd32_kmq_timedreceive(struct thread *td,
2824     struct freebsd32_kmq_timedreceive_args *uap)
2825 {
2826 	struct mqueue *mq;
2827 	struct file *fp;
2828 	struct timespec32 ets32;
2829 	struct timespec *abs_timeout, ets;
2830 	int error, waitok;
2831 
2832 	AUDIT_ARG_FD(uap->mqd);
2833 	error = getmq_read(td, uap->mqd, &fp, NULL, &mq);
2834 	if (error)
2835 		return (error);
2836 	if (uap->abs_timeout != NULL) {
2837 		error = copyin(uap->abs_timeout, &ets32, sizeof(ets32));
2838 		if (error != 0)
2839 			return (error);
2840 		CP(ets32, ets, tv_sec);
2841 		CP(ets32, ets, tv_nsec);
2842 		abs_timeout = &ets;
2843 	} else
2844 		abs_timeout = NULL;
2845 	waitok = !(fp->f_flag & O_NONBLOCK);
2846 	error = mqueue_receive(mq, uap->msg_ptr, uap->msg_len,
2847 		uap->msg_prio, waitok, abs_timeout);
2848 	fdrop(fp, td);
2849 	return (error);
2850 }
2851 
2852 int
2853 freebsd32_kmq_notify(struct thread *td, struct freebsd32_kmq_notify_args *uap)
2854 {
2855 	struct sigevent ev, *evp;
2856 	struct sigevent32 ev32;
2857 	int error;
2858 
2859 	if (uap->sigev == NULL) {
2860 		evp = NULL;
2861 	} else {
2862 		error = copyin(uap->sigev, &ev32, sizeof(ev32));
2863 		if (error != 0)
2864 			return (error);
2865 		error = convert_sigevent32(&ev32, &ev);
2866 		if (error != 0)
2867 			return (error);
2868 		evp = &ev;
2869 	}
2870 	return (kern_kmq_notify(td, uap->mqd, evp));
2871 }
2872 
2873 static struct syscall_helper_data mq32_syscalls[] = {
2874 	SYSCALL32_INIT_HELPER(freebsd32_kmq_open),
2875 	SYSCALL32_INIT_HELPER_F(freebsd32_kmq_setattr, SYF_CAPENABLED),
2876 	SYSCALL32_INIT_HELPER_F(freebsd32_kmq_timedsend, SYF_CAPENABLED),
2877 	SYSCALL32_INIT_HELPER_F(freebsd32_kmq_timedreceive, SYF_CAPENABLED),
2878 	SYSCALL32_INIT_HELPER_F(freebsd32_kmq_notify, SYF_CAPENABLED),
2879 	SYSCALL32_INIT_HELPER_COMPAT(kmq_unlink),
2880 	SYSCALL_INIT_LAST
2881 };
2882 #endif
2883 
2884 static int
2885 mqinit(void)
2886 {
2887 	int error;
2888 
2889 	error = syscall_helper_register(mq_syscalls, SY_THR_STATIC_KLD);
2890 	if (error != 0)
2891 		return (error);
2892 #ifdef COMPAT_FREEBSD32
2893 	error = syscall32_helper_register(mq32_syscalls, SY_THR_STATIC_KLD);
2894 	if (error != 0)
2895 		return (error);
2896 #endif
2897 	return (0);
2898 }
2899 
2900 static int
2901 mqunload(void)
2902 {
2903 
2904 #ifdef COMPAT_FREEBSD32
2905 	syscall32_helper_unregister(mq32_syscalls);
2906 #endif
2907 	syscall_helper_unregister(mq_syscalls);
2908 	return (0);
2909 }
2910 
2911 static int
2912 mq_modload(struct module *module, int cmd, void *arg)
2913 {
2914 	int error = 0;
2915 
2916 	error = vfs_modevent(module, cmd, arg);
2917 	if (error != 0)
2918 		return (error);
2919 
2920 	switch (cmd) {
2921 	case MOD_LOAD:
2922 		error = mqinit();
2923 		if (error != 0)
2924 			mqunload();
2925 		break;
2926 	case MOD_UNLOAD:
2927 		error = mqunload();
2928 		break;
2929 	default:
2930 		break;
2931 	}
2932 	return (error);
2933 }
2934 
2935 static moduledata_t mqueuefs_mod = {
2936 	"mqueuefs",
2937 	mq_modload,
2938 	&mqueuefs_vfsconf
2939 };
2940 DECLARE_MODULE(mqueuefs, mqueuefs_mod, SI_SUB_VFS, SI_ORDER_MIDDLE);
2941 MODULE_VERSION(mqueuefs, 1);
2942