[unix-history] / usr / src / sys / miscfs / fifofs / fifo_vnops.c

/*
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *	@(#)fifo_vnops.c	7.4 (Berkeley) %G%
 */

#include "param.h"
#include "time.h"
#include "namei.h"
#include "vnode.h"
#include "socket.h"
#include "socketvar.h"
#include "stat.h"
#include "ioctl.h"
#include "file.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;
};

int	fifo_lookup(),
	fifo_open(),
	fifo_read(),
	fifo_write(),
	fifo_strategy(),
	fifo_bmap(),
	fifo_ioctl(),
	fifo_select(),
	fifo_lock(),
	fifo_unlock(),
	fifo_close(),
	fifo_print(),
	fifo_ebadf(),
	fifo_badop(),
	fifo_nullop();

struct vnodeops fifo_vnodeops = {
	fifo_lookup,		/* lookup */
	fifo_badop,		/* create */
	fifo_badop,		/* mknod */
	fifo_open,		/* open */
	fifo_close,		/* close */
	fifo_ebadf,		/* access */
	fifo_ebadf,		/* getattr */
	fifo_ebadf,		/* setattr */
	fifo_read,		/* read */
	fifo_write,		/* write */
	fifo_ioctl,		/* ioctl */
	fifo_select,		/* select */
	fifo_badop,		/* mmap */
	fifo_nullop,		/* fsync */
	fifo_badop,		/* seek */
	fifo_badop,		/* remove */
	fifo_badop,		/* link */
	fifo_badop,		/* rename */
	fifo_badop,		/* mkdir */
	fifo_badop,		/* rmdir */
	fifo_badop,		/* symlink */
	fifo_badop,		/* readdir */
	fifo_badop,		/* readlink */
	fifo_badop,		/* abortop */
	fifo_nullop,		/* inactive */
	fifo_nullop,		/* reclaim */
	fifo_lock,		/* lock */
	fifo_unlock,		/* unlock */
	fifo_bmap,		/* bmap */
	fifo_badop,		/* strategy */
	fifo_print,		/* print */
	fifo_nullop,		/* islocked */
};

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

	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)
	register struct vnode *vp;
	int mode;
	struct ucred *cred;
{
	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;
		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)
			if (error = tsleep((caddr_t)&fip->fi_readers, PSOCK,
			    openstr, 0))
				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)
				if (error = tsleep((caddr_t)&fip->fi_writers,
				    PSOCK, openstr, 0))
					break;
		}
	}
	if (error)
		fifo_close(vp, mode, cred);
	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;

	if (uio->uio_rw != UIO_READ)
		panic("fifo_read mode");
	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;

	if (uio->uio_rw != UIO_WRITE)
		panic("fifo_write mode");
	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)
	struct vnode *vp;
	int com;
	caddr_t data;
	int fflag;
	struct ucred *cred;
{
	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));
}

/* ARGSUSED */
fifo_select(vp, which, fflag, cred)
	struct vnode *vp;
	int which, fflag;
	struct ucred *cred;
{
	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));
}

/*
 * 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)
	register struct vnode *vp;
	int fflag;
	struct ucred *cred;
{
	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 bad operation
 */
fifo_badop()
{

	panic("fifo_badop called");
	/* NOTREACHED */
}

/*
 * Fifo null operation
 */
fifo_nullop()
{

	return (0);
}
Commit	Line	Data
cc6b488e KM	1	/*
	2	* Copyright (c) 1990 The Regents of the University of California.
	3	* All rights reserved.
	4	*
dbf0c423	5	* %sccs.include.redist.c%
cc6b488e	6	*
dbf0c423	7	* @(#)fifo_vnops.c 7.4 (Berkeley) %G%
cc6b488e KM	8	*/
	9
	10	#include "param.h"
	11	#include "time.h"
	12	#include "namei.h"
	13	#include "vnode.h"
	14	#include "socket.h"
	15	#include "socketvar.h"
	16	#include "stat.h"
	17	#include "ioctl.h"
	18	#include "file.h"
	19	#include "errno.h"
	20	#include "malloc.h"
	21
	22	/*
	23	* This structure is associated with the FIFO vnode and stores
	24	* the state associated with the FIFO.
	25	*/
	26	struct fifoinfo {
	27	struct socket *fi_readsock;
	28	struct socket *fi_writesock;
	29	long fi_readers;
	30	long fi_writers;
	31	};
	32
	33	int fifo_lookup(),
	34	fifo_open(),
	35	fifo_read(),
	36	fifo_write(),
	37	fifo_strategy(),
	38	fifo_bmap(),
	39	fifo_ioctl(),
	40	fifo_select(),
	41	fifo_lock(),
	42	fifo_unlock(),
	43	fifo_close(),
	44	fifo_print(),
	45	fifo_ebadf(),
	46	fifo_badop(),
	47	fifo_nullop();
	48
	49	struct vnodeops fifo_vnodeops = {
	50	fifo_lookup, /* lookup */
	51	fifo_badop, /* create */
	52	fifo_badop, /* mknod */
	53	fifo_open, /* open */
	54	fifo_close, /* close */
	55	fifo_ebadf, /* access */
	56	fifo_ebadf, /* getattr */
	57	fifo_ebadf, /* setattr */
	58	fifo_read, /* read */
	59	fifo_write, /* write */
	60	fifo_ioctl, /* ioctl */
	61	fifo_select, /* select */
	62	fifo_badop, /* mmap */
	63	fifo_nullop, /* fsync */
	64	fifo_badop, /* seek */
	65	fifo_badop, /* remove */
	66	fifo_badop, /* link */
	67	fifo_badop, /* rename */
	68	fifo_badop, /* mkdir */
	69	fifo_badop, /* rmdir */
	70	fifo_badop, /* symlink */
	71	fifo_badop, /* readdir */
72	fifo_badop, /* readlink */
73	fifo_badop, /* abortop */
74	fifo_nullop, /* inactive */
75	fifo_nullop, /* reclaim */
76	fifo_lock, /* lock */
77	fifo_unlock, /* unlock */
78	fifo_bmap, /* bmap */
79	fifo_badop, /* strategy */
80	fifo_print, /* print */
81	fifo_nullop, /* islocked */
82	};
83
84	/*
85	* Trivial lookup routine that always fails.
86	*/
87	fifo_lookup(vp, ndp)
88	struct vnode *vp;
89	struct nameidata *ndp;
90	{
91
92	ndp->ni_dvp = vp;
93	ndp->ni_vp = NULL;
94	return (ENOTDIR);
95	}
96
97	/*
98	* Open called to set up a new instance of a fifo or
99	* to find an active instance of a fifo.
100	*/
101	/* ARGSUSED */
102	fifo_open(vp, mode, cred)
103	register struct vnode *vp;
104	int mode;
105	struct ucred *cred;
106	{
107	register struct fifoinfo *fip;
108	struct socket rso, wso;
109	int error;
bcc829cc	110	static char openstr[] = "fifo";
cc6b488e KM	111
	112	if ((mode & (FREAD\|FWRITE)) == (FREAD\|FWRITE))
	113	return (EINVAL);
	114	if ((fip = vp->v_fifoinfo) == NULL) {
	115	MALLOC(fip, struct fifoinfo , sizeof(fip), M_VNODE, M_WAITOK);
	116	vp->v_fifoinfo = fip;
ed89f575 KM	117	if (error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0)) {
	118	free(fip, M_VNODE);
	119	vp->v_fifoinfo = NULL;
cc6b488e	120	return (error);
ed89f575	121	}
cc6b488e KM	122	fip->fi_readsock = rso;
	123	if (error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0)) {
	124	(void)soclose(rso);
ed89f575 KM	125	free(fip, M_VNODE);
ed89f575 KM	126	vp->v_fifoinfo = NULL;
cc6b488e KM	127	return (error);
	128	}
	129	fip->fi_writesock = wso;
	130	if (error = unp_connect2(wso, rso)) {
	131	(void)soclose(wso);
	132	(void)soclose(rso);
ed89f575 KM	133	free(fip, M_VNODE);
ed89f575 KM	134	vp->v_fifoinfo = NULL;
cc6b488e KM	135	return (error);
	136	}
	137	wso->so_state \|= SS_CANTRCVMORE;
	138	rso->so_state \|= SS_CANTSENDMORE;
	139	}
	140	error = 0;
	141	if (mode & FREAD) {
	142	fip->fi_readers++;
	143	if (fip->fi_readers == 1) {
	144	fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
	145	if (fip->fi_writers > 0)
	146	wakeup((caddr_t)&fip->fi_writers);
	147	}
	148	if (mode & O_NONBLOCK)
	149	return (0);
	150	while (fip->fi_writers == 0)
bcc829cc MK	151	if (error = tsleep((caddr_t)&fip->fi_readers, PSOCK,
bcc829cc MK	152	openstr, 0))
cc6b488e KM	153	break;
	154	} else {
	155	fip->fi_writers++;
	156	if (fip->fi_readers == 0 && (mode & O_NONBLOCK)) {
	157	error = ENXIO;
	158	} else {
	159	if (fip->fi_writers == 1) {
	160	fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
	161	if (fip->fi_readers > 0)
	162	wakeup((caddr_t)&fip->fi_readers);
	163	}
	164	while (fip->fi_readers == 0)
bcc829cc MK	165	if (error = tsleep((caddr_t)&fip->fi_writers,
bcc829cc MK	166	PSOCK, openstr, 0))
cc6b488e KM	167	break;
	168	}
	169	}
	170	if (error)
	171	fifo_close(vp, mode, cred);
	172	return (error);
	173	}
	174
	175	/*
	176	* Vnode op for read
	177	*/
	178	/* ARGSUSED */
	179	fifo_read(vp, uio, ioflag, cred)
	180	struct vnode *vp;
	181	register struct uio *uio;
	182	int ioflag;
	183	struct ucred *cred;
	184	{
	185	register struct socket *rso = vp->v_fifoinfo->fi_readsock;
	186	int error, startresid;
	187
	188	if (uio->uio_rw != UIO_READ)
	189	panic("fifo_read mode");
	190	if (uio->uio_resid == 0)
	191	return (0);
	192	if (ioflag & IO_NDELAY)
	193	rso->so_state \|= SS_NBIO;
	194	startresid = uio->uio_resid;
	195	VOP_UNLOCK(vp);
	196	error = soreceive(rso, (struct mbuf *)0, uio, (int )0,
	197	(struct mbuf )0, (struct mbuf )0);
	198	VOP_LOCK(vp);
	199	/*
	200	* Clear EOF indication after first such return.
	201	*/
	202	if (uio->uio_resid == startresid)
	203	rso->so_state &= ~SS_CANTRCVMORE;
	204	if (ioflag & IO_NDELAY)
	205	rso->so_state &= ~SS_NBIO;
	206	return (error);
	207	}
	208
	209	/*
	210	* Vnode op for write
	211	*/
	212	/* ARGSUSED */
	213	fifo_write(vp, uio, ioflag, cred)
	214	struct vnode *vp;
	215	register struct uio *uio;
	216	int ioflag;
	217	struct ucred *cred;
	218	{
	219	struct socket *wso = vp->v_fifoinfo->fi_writesock;
	220	int error;
	221
	222	if (uio->uio_rw != UIO_WRITE)
	223	panic("fifo_write mode");
	224	if (ioflag & IO_NDELAY)
	225	wso->so_state \|= SS_NBIO;
	226	VOP_UNLOCK(vp);
	227	error = sosend(wso, (struct mbuf )0, uio, 0, (struct mbuf )0);
	228	VOP_LOCK(vp);
	229	if (ioflag & IO_NDELAY)
	230	wso->so_state &= ~SS_NBIO;
231	return (error);
232	}
233
234	/*
235	* Device ioctl operation.
236	*/
237	/* ARGSUSED */
238	fifo_ioctl(vp, com, data, fflag, cred)
239	struct vnode *vp;
240	int com;
241	caddr_t data;
242	int fflag;
243	struct ucred *cred;
244	{
245	struct file filetmp;
246	int error;
247
248	if (com == FIONBIO)
249	return (0);
250	if (fflag & FREAD)
251	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
252	else
253	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
254	return (soo_ioctl(&filetmp, com, data));
255	}
256
257	/* ARGSUSED */
258	fifo_select(vp, which, fflag, cred)
259	struct vnode *vp;
260	int which, fflag;
261	struct ucred *cred;
262	{
263	struct file filetmp;
264	int error;
265
266	if (fflag & FREAD)
267	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
268	else
269	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
270	return (soo_select(&filetmp, which));
271	}
272
273	/*
274	* This is a noop, simply returning what one has been given.
275	*/
276	fifo_bmap(vp, bn, vpp, bnp)
277	struct vnode *vp;
278	daddr_t bn;
279	struct vnode **vpp;
280	daddr_t *bnp;
281	{
282
283	if (vpp != NULL)
284	*vpp = vp;
285	if (bnp != NULL)
286	*bnp = bn;
287	return (0);
288	}
289
290	/*
291	* At the moment we do not do any locking.
292	*/
293	/* ARGSUSED */
294	fifo_lock(vp)
295	struct vnode *vp;
296	{
297
298	return (0);
299	}
300
301	/* ARGSUSED */
302	fifo_unlock(vp)
303	struct vnode *vp;
304	{
305
306	return (0);
307	}
308
309	/*
310	* Device close routine
311	*/
312	/* ARGSUSED */
313	fifo_close(vp, fflag, cred)
314	register struct vnode *vp;
315	int fflag;
316	struct ucred *cred;
317	{
318	register struct fifoinfo *fip = vp->v_fifoinfo;
319	int error1, error2;
320
321	if (fflag & FWRITE) {
322	fip->fi_writers--;
323	if (fip->fi_writers == 0)
324	socantrcvmore(fip->fi_readsock);
325	} else {
326	fip->fi_readers--;
327	if (fip->fi_readers == 0)
328	socantsendmore(fip->fi_writesock);
329	}
330	if (vp->v_usecount > 1)
331	return (0);
332	error1 = soclose(fip->fi_readsock);
333	error2 = soclose(fip->fi_writesock);
334	FREE(fip, M_VNODE);
335	vp->v_fifoinfo = NULL;
336	if (error1)
337	return (error1);
338	return (error2);
339	}
340
341	/*
342	* Print out the contents of a fifo vnode.
343	*/
344	fifo_print(vp)
345	struct vnode *vp;
346	{
347
348	printf("tag VT_NON");
349	fifo_printinfo(vp);
350	printf("\n");
351	}
352
353	/*
354	* Print out internal contents of a fifo vnode.
355	*/
356	fifo_printinfo(vp)
357	struct vnode *vp;
358	{
359	register struct fifoinfo *fip = vp->v_fifoinfo;
360
361	printf(", fifo with %d readers and %d writers",
362	fip->fi_readers, fip->fi_writers);
363	}
364
365	/*
366	* Fifo failed operation
367	*/
368	fifo_ebadf()
369	{
370
371	return (EBADF);
372	}
373
374	/*
375	* Fifo bad operation
376	*/
377	fifo_badop()
378	{
379
380	panic("fifo_badop called");
381	/* NOTREACHED */
382	}
383
384	/*
385	* Fifo null operation
386	*/
387	fifo_nullop()
388	{
389
390	return (0);
391	}