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1.1 root 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:
36: #include "param.h"
37: #include "time.h"
38: #include "namei.h"
39: #include "vnode.h"
40: #include "socket.h"
41: #include "socketvar.h"
42: #include "stat.h"
43: #include "systm.h"
44: #include "ioctl.h"
45: #include "file.h"
46: #include "fifo.h"
47: #include "errno.h"
48: #include "malloc.h"
49:
50: /*
51: * This structure is associated with the FIFO vnode and stores
52: * the state associated with the FIFO.
53: */
54: struct fifoinfo {
55: struct socket *fi_readsock;
56: struct socket *fi_writesock;
57: long fi_readers;
58: long fi_writers;
59: };
60:
61: struct vnodeops fifo_vnodeops = {
62: fifo_lookup, /* lookup */
63: fifo_create, /* create */
64: fifo_mknod, /* mknod */
65: fifo_open, /* open */
66: fifo_close, /* close */
67: fifo_access, /* access */
68: fifo_getattr, /* getattr */
69: fifo_setattr, /* setattr */
70: fifo_read, /* read */
71: fifo_write, /* write */
72: fifo_ioctl, /* ioctl */
73: fifo_select, /* select */
74: fifo_mmap, /* mmap */
75: fifo_fsync, /* fsync */
76: fifo_seek, /* seek */
77: fifo_remove, /* remove */
78: fifo_link, /* link */
79: fifo_rename, /* rename */
80: fifo_mkdir, /* mkdir */
81: fifo_rmdir, /* rmdir */
82: fifo_symlink, /* symlink */
83: fifo_readdir, /* readdir */
84: fifo_readlink, /* readlink */
85: fifo_abortop, /* abortop */
86: fifo_inactive, /* inactive */
87: fifo_reclaim, /* reclaim */
88: fifo_lock, /* lock */
89: fifo_unlock, /* unlock */
90: fifo_bmap, /* bmap */
91: fifo_strategy, /* strategy */
92: fifo_print, /* print */
93: fifo_islocked, /* islocked */
94: fifo_advlock, /* advlock */
95: };
96:
97: /*
98: * Trivial lookup routine that always fails.
99: */
100: /* ARGSUSED */
101: fifo_lookup(vp, ndp, p)
102: struct vnode *vp;
103: struct nameidata *ndp;
104: struct proc *p;
105: {
106:
107: ndp->ni_dvp = vp;
108: ndp->ni_vp = NULL;
109: return (ENOTDIR);
110: }
111:
112: /*
113: * Open called to set up a new instance of a fifo or
114: * to find an active instance of a fifo.
115: */
116: /* ARGSUSED */
117: fifo_open(vp, mode, cred, p)
118: register struct vnode *vp;
119: int mode;
120: struct ucred *cred;
121: struct proc *p;
122: {
123: register struct fifoinfo *fip;
124: struct socket *rso, *wso;
125: int error;
126: static char openstr[] = "fifo";
127:
128: if ((mode & (FREAD|FWRITE)) == (FREAD|FWRITE))
129: return (EINVAL);
130: if ((fip = vp->v_fifoinfo) == NULL) {
131: MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK);
132: vp->v_fifoinfo = fip;
133: if (error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0)) {
134: free(fip, M_VNODE);
135: vp->v_fifoinfo = NULL;
136: return (error);
137: }
138: fip->fi_readsock = rso;
139: if (error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0)) {
140: (void)soclose(rso);
141: free(fip, M_VNODE);
142: vp->v_fifoinfo = NULL;
143: return (error);
144: }
145: fip->fi_writesock = wso;
146: if (error = unp_connect2(wso, rso)) {
147: (void)soclose(wso);
148: (void)soclose(rso);
149: free(fip, M_VNODE);
150: vp->v_fifoinfo = NULL;
151: return (error);
152: }
153: wso->so_state |= SS_CANTRCVMORE;
154: rso->so_state |= SS_CANTSENDMORE;
155: }
156: error = 0;
157: if (mode & FREAD) {
158: fip->fi_readers++;
159: if (fip->fi_readers == 1) {
160: fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
161: if (fip->fi_writers > 0)
162: wakeup((caddr_t)&fip->fi_writers);
163: }
164: if (mode & O_NONBLOCK)
165: return (0);
166: while (fip->fi_writers == 0)
167: if (error = tsleep((caddr_t)&fip->fi_readers, PSOCK,
168: openstr, 0))
169: break;
170: } else {
171: fip->fi_writers++;
172: if (fip->fi_readers == 0 && (mode & O_NONBLOCK)) {
173: error = ENXIO;
174: } else {
175: if (fip->fi_writers == 1) {
176: fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
177: if (fip->fi_readers > 0)
178: wakeup((caddr_t)&fip->fi_readers);
179: }
180: while (fip->fi_readers == 0)
181: if (error = tsleep((caddr_t)&fip->fi_writers,
182: PSOCK, openstr, 0))
183: break;
184: }
185: }
186: if (error)
187: fifo_close(vp, mode, cred, p);
188: return (error);
189: }
190:
191: /*
192: * Vnode op for read
193: */
194: /* ARGSUSED */
195: fifo_read(vp, uio, ioflag, cred)
196: struct vnode *vp;
197: register struct uio *uio;
198: int ioflag;
199: struct ucred *cred;
200: {
201: register struct socket *rso = vp->v_fifoinfo->fi_readsock;
202: int error, startresid;
203:
204: #ifdef DIAGNOSTIC
205: if (uio->uio_rw != UIO_READ)
206: panic("fifo_read mode");
207: #endif
208: if (uio->uio_resid == 0)
209: return (0);
210: if (ioflag & IO_NDELAY)
211: rso->so_state |= SS_NBIO;
212: startresid = uio->uio_resid;
213: VOP_UNLOCK(vp);
214: error = soreceive(rso, (struct mbuf **)0, uio, (int *)0,
215: (struct mbuf **)0, (struct mbuf **)0);
216: VOP_LOCK(vp);
217: /*
218: * Clear EOF indication after first such return.
219: */
220: if (uio->uio_resid == startresid)
221: rso->so_state &= ~SS_CANTRCVMORE;
222: if (ioflag & IO_NDELAY)
223: rso->so_state &= ~SS_NBIO;
224: return (error);
225: }
226:
227: /*
228: * Vnode op for write
229: */
230: /* ARGSUSED */
231: fifo_write(vp, uio, ioflag, cred)
232: struct vnode *vp;
233: register struct uio *uio;
234: int ioflag;
235: struct ucred *cred;
236: {
237: struct socket *wso = vp->v_fifoinfo->fi_writesock;
238: int error;
239:
240: #ifdef DIAGNOSTIC
241: if (uio->uio_rw != UIO_WRITE)
242: panic("fifo_write mode");
243: #endif
244: if (ioflag & IO_NDELAY)
245: wso->so_state |= SS_NBIO;
246: VOP_UNLOCK(vp);
247: error = sosend(wso, (struct mbuf *)0, uio, 0, (struct mbuf *)0);
248: VOP_LOCK(vp);
249: if (ioflag & IO_NDELAY)
250: wso->so_state &= ~SS_NBIO;
251: return (error);
252: }
253:
254: /*
255: * Device ioctl operation.
256: */
257: /* ARGSUSED */
258: fifo_ioctl(vp, com, data, fflag, cred, p)
259: struct vnode *vp;
260: int com;
261: caddr_t data;
262: int fflag;
263: struct ucred *cred;
264: struct proc *p;
265: {
266: struct file filetmp;
267: int error;
268:
269: if (com == FIONBIO)
270: return (0);
271: if (fflag & FREAD)
272: filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
273: else
274: filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
275: return (soo_ioctl(&filetmp, com, data, p));
276: }
277:
278: /* ARGSUSED */
279: fifo_select(vp, which, fflag, cred, p)
280: struct vnode *vp;
281: int which, fflag;
282: struct ucred *cred;
283: struct proc *p;
284: {
285: struct file filetmp;
286: int error;
287:
288: if (fflag & FREAD)
289: filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
290: else
291: filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
292: return (soo_select(&filetmp, which, p));
293: }
294:
295: /*
296: * This is a noop, simply returning what one has been given.
297: */
298: fifo_bmap(vp, bn, vpp, bnp)
299: struct vnode *vp;
300: daddr_t bn;
301: struct vnode **vpp;
302: daddr_t *bnp;
303: {
304:
305: if (vpp != NULL)
306: *vpp = vp;
307: if (bnp != NULL)
308: *bnp = bn;
309: return (0);
310: }
311:
312: /*
313: * At the moment we do not do any locking.
314: */
315: /* ARGSUSED */
316: fifo_lock(vp)
317: struct vnode *vp;
318: {
319:
320: return (0);
321: }
322:
323: /* ARGSUSED */
324: fifo_unlock(vp)
325: struct vnode *vp;
326: {
327:
328: return (0);
329: }
330:
331: /*
332: * Device close routine
333: */
334: /* ARGSUSED */
335: fifo_close(vp, fflag, cred, p)
336: register struct vnode *vp;
337: int fflag;
338: struct ucred *cred;
339: struct proc *p;
340: {
341: register struct fifoinfo *fip = vp->v_fifoinfo;
342: int error1, error2;
343:
344: if (fflag & FWRITE) {
345: fip->fi_writers--;
346: if (fip->fi_writers == 0)
347: socantrcvmore(fip->fi_readsock);
348: } else {
349: fip->fi_readers--;
350: if (fip->fi_readers == 0)
351: socantsendmore(fip->fi_writesock);
352: }
353: if (vp->v_usecount > 1)
354: return (0);
355: error1 = soclose(fip->fi_readsock);
356: error2 = soclose(fip->fi_writesock);
357: FREE(fip, M_VNODE);
358: vp->v_fifoinfo = NULL;
359: if (error1)
360: return (error1);
361: return (error2);
362: }
363:
364: /*
365: * Print out the contents of a fifo vnode.
366: */
367: fifo_print(vp)
368: struct vnode *vp;
369: {
370:
371: printf("tag VT_NON");
372: fifo_printinfo(vp);
373: printf("\n");
374: }
375:
376: /*
377: * Print out internal contents of a fifo vnode.
378: */
379: fifo_printinfo(vp)
380: struct vnode *vp;
381: {
382: register struct fifoinfo *fip = vp->v_fifoinfo;
383:
384: printf(", fifo with %d readers and %d writers",
385: fip->fi_readers, fip->fi_writers);
386: }
387:
388: /*
389: * Fifo failed operation
390: */
391: fifo_ebadf()
392: {
393:
394: return (EBADF);
395: }
396:
397: /*
398: * Fifo advisory byte-level locks.
399: */
400: /* ARGSUSED */
401: fifo_advlock(vp, id, op, fl, flags)
402: struct vnode *vp;
403: caddr_t id;
404: int op;
405: struct flock *fl;
406: int flags;
407: {
408:
409: return (EOPNOTSUPP);
410: }
411:
412: /*
413: * Fifo bad operation
414: */
415: fifo_badop()
416: {
417:
418: panic("fifo_badop called");
419: /* NOTREACHED */
420: }
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