[unix-history] / sys / kern / fifo_vnops.c

/*
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)fifo_vnops.c	7.7 (Berkeley) 4/15/91
 *
 * PATCHES MAGIC                LEVEL   PATCH THAT GOT US HERE
 * --------------------         -----   ----------------------
 * CURRENT PATCH LEVEL:         1       00141
 * --------------------         -----   ----------------------
 *
 * 20 Apr 93	Jay Fenlason	1. fi_{readers|fi_writers} of fifoinfo init to 0
 *				2. fifo_open() was calling tsleep() without
 *				unlocking the inode of the fifo
 */

#include "param.h"
#include "time.h"
#include "namei.h"
#include "vnode.h"
#include "socket.h"
#include "socketvar.h"
#include "stat.h"
#include "systm.h"
#include "ioctl.h"
#include "file.h"
#include "fifo.h"
#include "errno.h"
#include "malloc.h"

/*
 * This structure is associated with the FIFO vnode and stores
 * the state associated with the FIFO.
 */
struct fifoinfo {
	struct socket	*fi_readsock;
	struct socket	*fi_writesock;
	long		fi_readers;
	long		fi_writers;
};

struct vnodeops fifo_vnodeops = {
	fifo_lookup,		/* lookup */
	fifo_create,		/* create */
	fifo_mknod,		/* mknod */
	fifo_open,		/* open */
	fifo_close,		/* close */
	fifo_access,		/* access */
	fifo_getattr,		/* getattr */
	fifo_setattr,		/* setattr */
	fifo_read,		/* read */
	fifo_write,		/* write */
	fifo_ioctl,		/* ioctl */
	fifo_select,		/* select */
	fifo_mmap,		/* mmap */
	fifo_fsync,		/* fsync */
	fifo_seek,		/* seek */
	fifo_remove,		/* remove */
	fifo_link,		/* link */
	fifo_rename,		/* rename */
	fifo_mkdir,		/* mkdir */
	fifo_rmdir,		/* rmdir */
	fifo_symlink,		/* symlink */
	fifo_readdir,		/* readdir */
	fifo_readlink,		/* readlink */
	fifo_abortop,		/* abortop */
	fifo_inactive,		/* inactive */
	fifo_reclaim,		/* reclaim */
	fifo_lock,		/* lock */
	fifo_unlock,		/* unlock */
	fifo_bmap,		/* bmap */
	fifo_strategy,		/* strategy */
	fifo_print,		/* print */
	fifo_islocked,		/* islocked */
	fifo_advlock,		/* advlock */
};

/*
 * Trivial lookup routine that always fails.
 */
/* ARGSUSED */
fifo_lookup(vp, ndp, p)
	struct vnode *vp;
	struct nameidata *ndp;
	struct proc *p;
{

	ndp->ni_dvp = vp;
	ndp->ni_vp = NULL;
	return (ENOTDIR);
}

/*
 * Open called to set up a new instance of a fifo or
 * to find an active instance of a fifo.
 */
/* ARGSUSED */
fifo_open(vp, mode, cred, p)
	register struct vnode *vp;
	int mode;
	struct ucred *cred;
	struct proc *p;
{
	register struct fifoinfo *fip;
	struct socket *rso, *wso;
	int error;
	static char openstr[] = "fifo";

	if ((mode & (FREAD|FWRITE)) == (FREAD|FWRITE))
		return (EINVAL);
	if ((fip = vp->v_fifoinfo) == NULL) {
		MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK);
		vp->v_fifoinfo = fip;
		fip->fi_readers = fip->fi_writers = 0;
		if (error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0)) {
			free(fip, M_VNODE);
			vp->v_fifoinfo = NULL;
			return (error);
		}
		fip->fi_readsock = rso;
		if (error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0)) {
			(void)soclose(rso);
			free(fip, M_VNODE);
			vp->v_fifoinfo = NULL;
			return (error);
		}
		fip->fi_writesock = wso;
		if (error = unp_connect2(wso, rso)) {
			(void)soclose(wso);
			(void)soclose(rso);
			free(fip, M_VNODE);
			vp->v_fifoinfo = NULL;
			return (error);
		}
		wso->so_state |= SS_CANTRCVMORE;
		rso->so_state |= SS_CANTSENDMORE;
	}
	error = 0;
	if (mode & FREAD) {
		fip->fi_readers++;
		if (fip->fi_readers == 1) {
			fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
			if (fip->fi_writers > 0)
				wakeup((caddr_t)&fip->fi_writers);
		}
		if (mode & O_NONBLOCK)
			return (0);
		while (fip->fi_writers == 0) {
			VOP_UNLOCK(vp);
			error = tsleep((caddr_t)&fip->fi_readers, PSOCK | PCATCH,
			    		openstr, 0);
			VOP_LOCK(vp);
			if (error)
				break;
		}
	} else {
		fip->fi_writers++;
		if (fip->fi_readers == 0 && (mode & O_NONBLOCK)) {
			error = ENXIO;
		} else {
			if (fip->fi_writers == 1) {
				fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
				if (fip->fi_readers > 0)
					wakeup((caddr_t)&fip->fi_readers);
			}
			while (fip->fi_readers == 0) {
				VOP_UNLOCK(vp);
				error = tsleep((caddr_t)&fip->fi_writers,
				    		PSOCK | PCATCH, openstr, 0);
				VOP_LOCK(vp);
				if (error)
					break;
			}
		}
	}
	if (error)
		fifo_close(vp, mode, cred, p);
	return (error);
}

/*
 * Vnode op for read
 */
/* ARGSUSED */
fifo_read(vp, uio, ioflag, cred)
	struct vnode *vp;
	register struct uio *uio;
	int ioflag;
	struct ucred *cred;
{
	register struct socket *rso = vp->v_fifoinfo->fi_readsock;
	int error, startresid;

#ifdef DIAGNOSTIC
	if (uio->uio_rw != UIO_READ)
		panic("fifo_read mode");
#endif
	if (uio->uio_resid == 0)
		return (0);
	if (ioflag & IO_NDELAY)
		rso->so_state |= SS_NBIO;
	startresid = uio->uio_resid;
	VOP_UNLOCK(vp);
	error = soreceive(rso, (struct mbuf **)0, uio, (int *)0,
		(struct mbuf **)0, (struct mbuf **)0);
	VOP_LOCK(vp);
	/*
	 * Clear EOF indication after first such return.
	 */
	if (uio->uio_resid == startresid)
		rso->so_state &= ~SS_CANTRCVMORE;
	if (ioflag & IO_NDELAY)
		rso->so_state &= ~SS_NBIO;
	return (error);
}

/*
 * Vnode op for write
 */
/* ARGSUSED */
fifo_write(vp, uio, ioflag, cred)
	struct vnode *vp;
	register struct uio *uio;
	int ioflag;
	struct ucred *cred;
{
	struct socket *wso = vp->v_fifoinfo->fi_writesock;
	int error;

#ifdef DIAGNOSTIC
	if (uio->uio_rw != UIO_WRITE)
		panic("fifo_write mode");
#endif
	if (ioflag & IO_NDELAY)
		wso->so_state |= SS_NBIO;
	VOP_UNLOCK(vp);
	error = sosend(wso, (struct mbuf *)0, uio, 0, (struct mbuf *)0);
	VOP_LOCK(vp);
	if (ioflag & IO_NDELAY)
		wso->so_state &= ~SS_NBIO;
	return (error);
}

/*
 * Device ioctl operation.
 */
/* ARGSUSED */
fifo_ioctl(vp, com, data, fflag, cred, p)
	struct vnode *vp;
	int com;
	caddr_t data;
	int fflag;
	struct ucred *cred;
	struct proc *p;
{
	struct file filetmp;
	int error;

	if (com == FIONBIO)
		return (0);
	if (fflag & FREAD)
		filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
	else
		filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
	return (soo_ioctl(&filetmp, com, data, p));
}

/* ARGSUSED */
fifo_select(vp, which, fflag, cred, p)
	struct vnode *vp;
	int which, fflag;
	struct ucred *cred;
	struct proc *p;
{
	struct file filetmp;
	int error;

	if (fflag & FREAD)
		filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
	else
		filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
	return (soo_select(&filetmp, which, p));
}

/*
 * This is a noop, simply returning what one has been given.
 */
fifo_bmap(vp, bn, vpp, bnp)
	struct vnode *vp;
	daddr_t bn;
	struct vnode **vpp;
	daddr_t *bnp;
{

	if (vpp != NULL)
		*vpp = vp;
	if (bnp != NULL)
		*bnp = bn;
	return (0);
}

/*
 * At the moment we do not do any locking.
 */
/* ARGSUSED */
fifo_lock(vp)
	struct vnode *vp;
{

	return (0);
}

/* ARGSUSED */
fifo_unlock(vp)
	struct vnode *vp;
{

	return (0);
}

/*
 * Device close routine
 */
/* ARGSUSED */
fifo_close(vp, fflag, cred, p)
	register struct vnode *vp;
	int fflag;
	struct ucred *cred;
	struct proc *p;
{
	register struct fifoinfo *fip = vp->v_fifoinfo;
	int error1, error2;

	if (fflag & FWRITE) {
		fip->fi_writers--;
		if (fip->fi_writers == 0)
			socantrcvmore(fip->fi_readsock);
	} else {
		fip->fi_readers--;
		if (fip->fi_readers == 0)
			socantsendmore(fip->fi_writesock);
	}
	if (vp->v_usecount > 1)
		return (0);
	error1 = soclose(fip->fi_readsock);
	error2 = soclose(fip->fi_writesock);
	FREE(fip, M_VNODE);
	vp->v_fifoinfo = NULL;
	if (error1)
		return (error1);
	return (error2);
}

/*
 * Print out the contents of a fifo vnode.
 */
fifo_print(vp)
	struct vnode *vp;
{

	printf("tag VT_NON");
	fifo_printinfo(vp);
	printf("\n");
}

/*
 * Print out internal contents of a fifo vnode.
 */
fifo_printinfo(vp)
	struct vnode *vp;
{
	register struct fifoinfo *fip = vp->v_fifoinfo;

	printf(", fifo with %d readers and %d writers",
		fip->fi_readers, fip->fi_writers);
}

/*
 * Fifo failed operation
 */
fifo_ebadf()
{

	return (EBADF);
}

/*
 * Fifo advisory byte-level locks.
 */
/* ARGSUSED */
fifo_advlock(vp, id, op, fl, flags)
	struct vnode *vp;
	caddr_t id;
	int op;
	struct flock *fl;
	int flags;
{

	return (EOPNOTSUPP);
}

/*
 * Fifo bad operation
 */
fifo_badop()
{

	panic("fifo_badop called");
	/* NOTREACHED */
}
Commit	Line	Data
15637ed4 RG	1	/*
	2	* Copyright (c) 1990 The Regents of the University of California.
	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. Neither the name of the University nor the names of its contributors
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	22	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	25	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	26	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	27	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	28	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	29	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	30	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	31	* SUCH DAMAGE.
	32	*
	33	* @(#)fifo_vnops.c 7.7 (Berkeley) 4/15/91
	34	*
	35	* PATCHES MAGIC LEVEL PATCH THAT GOT US HERE
	36	* -------------------- ----- ----------------------
	37	* CURRENT PATCH LEVEL: 1 00141
	38	* -------------------- ----- ----------------------
	39	*
	40	* 20 Apr 93 Jay Fenlason 1. fi_{readers\|fi_writers} of fifoinfo init to 0
	41	* 2. fifo_open() was calling tsleep() without
	42	* unlocking the inode of the fifo
	43	*/
	44
	45	#include "param.h"
	46	#include "time.h"
	47	#include "namei.h"
	48	#include "vnode.h"
	49	#include "socket.h"
	50	#include "socketvar.h"
	51	#include "stat.h"
	52	#include "systm.h"
	53	#include "ioctl.h"
	54	#include "file.h"
	55	#include "fifo.h"
	56	#include "errno.h"
	57	#include "malloc.h"
	58
	59	/*
	60	* This structure is associated with the FIFO vnode and stores
	61	* the state associated with the FIFO.
	62	*/
	63	struct fifoinfo {
	64	struct socket *fi_readsock;
65	struct socket *fi_writesock;
66	long fi_readers;
67	long fi_writers;
68	};
69
70	struct vnodeops fifo_vnodeops = {
71	fifo_lookup, /* lookup */
72	fifo_create, /* create */
73	fifo_mknod, /* mknod */
74	fifo_open, /* open */
75	fifo_close, /* close */
76	fifo_access, /* access */
77	fifo_getattr, /* getattr */
78	fifo_setattr, /* setattr */
79	fifo_read, /* read */
80	fifo_write, /* write */
81	fifo_ioctl, /* ioctl */
82	fifo_select, /* select */
83	fifo_mmap, /* mmap */
84	fifo_fsync, /* fsync */
85	fifo_seek, /* seek */
86	fifo_remove, /* remove */
87	fifo_link, /* link */
88	fifo_rename, /* rename */
89	fifo_mkdir, /* mkdir */
90	fifo_rmdir, /* rmdir */
91	fifo_symlink, /* symlink */
92	fifo_readdir, /* readdir */
93	fifo_readlink, /* readlink */
94	fifo_abortop, /* abortop */
95	fifo_inactive, /* inactive */
96	fifo_reclaim, /* reclaim */
97	fifo_lock, /* lock */
98	fifo_unlock, /* unlock */
99	fifo_bmap, /* bmap */
100	fifo_strategy, /* strategy */
101	fifo_print, /* print */
102	fifo_islocked, /* islocked */
103	fifo_advlock, /* advlock */
104	};
105
106	/*
107	* Trivial lookup routine that always fails.
108	*/
109	/* ARGSUSED */
110	fifo_lookup(vp, ndp, p)
111	struct vnode *vp;
112	struct nameidata *ndp;
113	struct proc *p;
114	{
115
116	ndp->ni_dvp = vp;
117	ndp->ni_vp = NULL;
118	return (ENOTDIR);
119	}
120
121	/*
122	* Open called to set up a new instance of a fifo or
123	* to find an active instance of a fifo.
124	*/
125	/* ARGSUSED */
126	fifo_open(vp, mode, cred, p)
127	register struct vnode *vp;
128	int mode;
129	struct ucred *cred;
130	struct proc *p;
131	{
132	register struct fifoinfo *fip;
133	struct socket rso, wso;
134	int error;
135	static char openstr[] = "fifo";
136
137	if ((mode & (FREAD\|FWRITE)) == (FREAD\|FWRITE))
138	return (EINVAL);
139	if ((fip = vp->v_fifoinfo) == NULL) {
140	MALLOC(fip, struct fifoinfo , sizeof(fip), M_VNODE, M_WAITOK);
141	vp->v_fifoinfo = fip;
142	fip->fi_readers = fip->fi_writers = 0;
143	if (error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0)) {
144	free(fip, M_VNODE);
145	vp->v_fifoinfo = NULL;
146	return (error);
147	}
148	fip->fi_readsock = rso;
149	if (error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0)) {
150	(void)soclose(rso);
151	free(fip, M_VNODE);
152	vp->v_fifoinfo = NULL;
153	return (error);
154	}
155	fip->fi_writesock = wso;
156	if (error = unp_connect2(wso, rso)) {
157	(void)soclose(wso);
158	(void)soclose(rso);
159	free(fip, M_VNODE);
160	vp->v_fifoinfo = NULL;
161	return (error);
162	}
163	wso->so_state \|= SS_CANTRCVMORE;
164	rso->so_state \|= SS_CANTSENDMORE;
165	}
166	error = 0;
167	if (mode & FREAD) {
168	fip->fi_readers++;
169	if (fip->fi_readers == 1) {
170	fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
171	if (fip->fi_writers > 0)
172	wakeup((caddr_t)&fip->fi_writers);
173	}
174	if (mode & O_NONBLOCK)
175	return (0);
176	while (fip->fi_writers == 0) {
177	VOP_UNLOCK(vp);
178	error = tsleep((caddr_t)&fip->fi_readers, PSOCK \| PCATCH,
179	openstr, 0);
180	VOP_LOCK(vp);
181	if (error)
182	break;
183	}
184	} else {
185	fip->fi_writers++;
186	if (fip->fi_readers == 0 && (mode & O_NONBLOCK)) {
187	error = ENXIO;
188	} else {
189	if (fip->fi_writers == 1) {
190	fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
191	if (fip->fi_readers > 0)
192	wakeup((caddr_t)&fip->fi_readers);
193	}
194	while (fip->fi_readers == 0) {
195	VOP_UNLOCK(vp);
196	error = tsleep((caddr_t)&fip->fi_writers,
197	PSOCK \| PCATCH, openstr, 0);
198	VOP_LOCK(vp);
199	if (error)
200	break;
201	}
202	}
203	}
204	if (error)
205	fifo_close(vp, mode, cred, p);
206	return (error);
207	}
208
209	/*
210	* Vnode op for read
211	*/
212	/* ARGSUSED */
213	fifo_read(vp, uio, ioflag, cred)
214	struct vnode *vp;
215	register struct uio *uio;
216	int ioflag;
217	struct ucred *cred;
218	{
219	register struct socket *rso = vp->v_fifoinfo->fi_readsock;
220	int error, startresid;
221
222	#ifdef DIAGNOSTIC
223	if (uio->uio_rw != UIO_READ)
224	panic("fifo_read mode");
225	#endif
226	if (uio->uio_resid == 0)
227	return (0);
228	if (ioflag & IO_NDELAY)
229	rso->so_state \|= SS_NBIO;
230	startresid = uio->uio_resid;
231	VOP_UNLOCK(vp);
232	error = soreceive(rso, (struct mbuf *)0, uio, (int )0,
233	(struct mbuf )0, (struct mbuf )0);
234	VOP_LOCK(vp);
235	/*
236	* Clear EOF indication after first such return.
237	*/
238	if (uio->uio_resid == startresid)
239	rso->so_state &= ~SS_CANTRCVMORE;
240	if (ioflag & IO_NDELAY)
241	rso->so_state &= ~SS_NBIO;
242	return (error);
243	}
244
245	/*
246	* Vnode op for write
247	*/
248	/* ARGSUSED */
249	fifo_write(vp, uio, ioflag, cred)
250	struct vnode *vp;
251	register struct uio *uio;
252	int ioflag;
253	struct ucred *cred;
254	{
255	struct socket *wso = vp->v_fifoinfo->fi_writesock;
256	int error;
257
258	#ifdef DIAGNOSTIC
259	if (uio->uio_rw != UIO_WRITE)
260	panic("fifo_write mode");
261	#endif
262	if (ioflag & IO_NDELAY)
263	wso->so_state \|= SS_NBIO;
264	VOP_UNLOCK(vp);
265	error = sosend(wso, (struct mbuf )0, uio, 0, (struct mbuf )0);
266	VOP_LOCK(vp);
267	if (ioflag & IO_NDELAY)
268	wso->so_state &= ~SS_NBIO;
269	return (error);
270	}
271
272	/*
273	* Device ioctl operation.
274	*/
275	/* ARGSUSED */
276	fifo_ioctl(vp, com, data, fflag, cred, p)
277	struct vnode *vp;
278	int com;
279	caddr_t data;
280	int fflag;
281	struct ucred *cred;
282	struct proc *p;
283	{
284	struct file filetmp;
285	int error;
286
287	if (com == FIONBIO)
288	return (0);
289	if (fflag & FREAD)
290	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
291	else
292	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
293	return (soo_ioctl(&filetmp, com, data, p));
294	}
295
296	/* ARGSUSED */
297	fifo_select(vp, which, fflag, cred, p)
298	struct vnode *vp;
299	int which, fflag;
300	struct ucred *cred;
301	struct proc *p;
302	{
303	struct file filetmp;
304	int error;
305
306	if (fflag & FREAD)
307	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
308	else
309	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
310	return (soo_select(&filetmp, which, p));
311	}
312
313	/*
314	* This is a noop, simply returning what one has been given.
315	*/
316	fifo_bmap(vp, bn, vpp, bnp)
317	struct vnode *vp;
318	daddr_t bn;
319	struct vnode **vpp;
320	daddr_t *bnp;
321	{
322
323	if (vpp != NULL)
324	*vpp = vp;
325	if (bnp != NULL)
326	*bnp = bn;
327	return (0);
328	}
329
330	/*
331	* At the moment we do not do any locking.
332	*/
333	/* ARGSUSED */
334	fifo_lock(vp)
335	struct vnode *vp;
336	{
337
338	return (0);
339	}
340
341	/* ARGSUSED */
342	fifo_unlock(vp)
343	struct vnode *vp;
344	{
345
346	return (0);
347	}
348
349	/*
350	* Device close routine
351	*/
352	/* ARGSUSED */
353	fifo_close(vp, fflag, cred, p)
354	register struct vnode *vp;
355	int fflag;
356	struct ucred *cred;
357	struct proc *p;
358	{
359	register struct fifoinfo *fip = vp->v_fifoinfo;
360	int error1, error2;
361
362	if (fflag & FWRITE) {
363	fip->fi_writers--;
364	if (fip->fi_writers == 0)
365	socantrcvmore(fip->fi_readsock);
366	} else {
367	fip->fi_readers--;
368	if (fip->fi_readers == 0)
369	socantsendmore(fip->fi_writesock);
370	}
371	if (vp->v_usecount > 1)
372	return (0);
373	error1 = soclose(fip->fi_readsock);
374	error2 = soclose(fip->fi_writesock);
375	FREE(fip, M_VNODE);
376	vp->v_fifoinfo = NULL;
377	if (error1)
378	return (error1);
379	return (error2);
380	}
381
382	/*
383	* Print out the contents of a fifo vnode.
384	*/
385	fifo_print(vp)
386	struct vnode *vp;
387	{
388
389	printf("tag VT_NON");
390	fifo_printinfo(vp);
391	printf("\n");
392	}
393
394	/*
395	* Print out internal contents of a fifo vnode.
396	*/
397	fifo_printinfo(vp)
398	struct vnode *vp;
399	{
400	register struct fifoinfo *fip = vp->v_fifoinfo;
401
402	printf(", fifo with %d readers and %d writers",
403	fip->fi_readers, fip->fi_writers);
404	}
405
406	/*
407	* Fifo failed operation
408	*/
409	fifo_ebadf()
410	{
411
412	return (EBADF);
413	}
414
415	/*
416	* Fifo advisory byte-level locks.
417	*/
418	/* ARGSUSED */
419	fifo_advlock(vp, id, op, fl, flags)
420	struct vnode *vp;
421	caddr_t id;
422	int op;
423	struct flock *fl;
424	int flags;
425	{
426
427	return (EOPNOTSUPP);
428	}
429
430	/*
431	* Fifo bad operation
432	*/
433	fifo_badop()
434	{
435
436	panic("fifo_badop called");
437	/* NOTREACHED */
438	}