xref: /netbsd-src/sys/coda/coda_psdev.c (revision 7330f729ccf0bd976a06f95fad452fe774fc7fd1)
1 /*	$NetBSD: coda_psdev.c,v 1.58 2017/10/25 08:12:38 maya Exp $	*/
2 
3 /*
4  *
5  *             Coda: an Experimental Distributed File System
6  *                              Release 3.1
7  *
8  *           Copyright (c) 1987-1998 Carnegie Mellon University
9  *                          All Rights Reserved
10  *
11  * Permission  to  use, copy, modify and distribute this software and its
12  * documentation is hereby granted,  provided  that  both  the  copyright
13  * notice  and  this  permission  notice  appear  in  all  copies  of the
14  * software, derivative works or  modified  versions,  and  any  portions
15  * thereof, and that both notices appear in supporting documentation, and
16  * that credit is given to Carnegie Mellon University  in  all  documents
17  * and publicity pertaining to direct or indirect use of this code or its
18  * derivatives.
19  *
20  * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS  KNOWN  TO  HAVE  BUGS,
21  * SOME  OF  WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON ALLOWS
22  * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.   CARNEGIE  MELLON
23  * DISCLAIMS  ANY  LIABILITY  OF  ANY  KIND  FOR  ANY  DAMAGES WHATSOEVER
24  * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE  OR  OF
25  * ANY DERIVATIVE WORK.
26  *
27  * Carnegie  Mellon  encourages  users  of  this  software  to return any
28  * improvements or extensions that  they  make,  and  to  grant  Carnegie
29  * Mellon the rights to redistribute these changes without encumbrance.
30  *
31  * 	@(#) coda/coda_psdev.c,v 1.1.1.1 1998/08/29 21:26:45 rvb Exp $
32  */
33 
34 /*
35  * Mach Operating System
36  * Copyright (c) 1989 Carnegie-Mellon University
37  * All rights reserved.  The CMU software License Agreement specifies
38  * the terms and conditions for use and redistribution.
39  */
40 
41 /*
42  * This code was written for the Coda file system at Carnegie Mellon
43  * University.  Contributers include David Steere, James Kistler, and
44  * M. Satyanarayanan.  */
45 
46 /* These routines define the pseudo device for communication between
47  * Coda's Venus and Minicache in Mach 2.6. They used to be in cfs_subr.c,
48  * but I moved them to make it easier to port the Minicache without
49  * porting coda. -- DCS 10/12/94
50  *
51  * Following code depends on file-system CODA.
52  */
53 
54 /* These routines are the device entry points for Venus. */
55 
56 #include <sys/cdefs.h>
57 __KERNEL_RCSID(0, "$NetBSD: coda_psdev.c,v 1.58 2017/10/25 08:12:38 maya Exp $");
58 
59 extern int coda_nc_initialized;    /* Set if cache has been initialized */
60 
61 #include <sys/param.h>
62 #include <sys/systm.h>
63 #include <sys/kernel.h>
64 #include <sys/malloc.h>
65 #include <sys/proc.h>
66 #include <sys/mount.h>
67 #include <sys/file.h>
68 #include <sys/ioctl.h>
69 #include <sys/poll.h>
70 #include <sys/select.h>
71 #include <sys/conf.h>
72 #include <sys/atomic.h>
73 #include <sys/module.h>
74 
75 #include <coda/coda.h>
76 #include <coda/cnode.h>
77 #include <coda/coda_namecache.h>
78 #include <coda/coda_io.h>
79 
80 #include "ioconf.h"
81 
82 #define CTL_C
83 
84 int coda_psdev_print_entry = 0;
85 static
86 int outstanding_upcalls = 0;
87 int coda_call_sleep = PZERO - 1;
88 #ifdef	CTL_C
89 int coda_pcatch = PCATCH;
90 #else
91 #endif
92 
93 int coda_kernel_version = CODA_KERNEL_VERSION;
94 
95 #define ENTRY if(coda_psdev_print_entry) myprintf(("Entered %s\n",__func__))
96 
97 dev_type_open(vc_nb_open);
98 dev_type_close(vc_nb_close);
99 dev_type_read(vc_nb_read);
100 dev_type_write(vc_nb_write);
101 dev_type_ioctl(vc_nb_ioctl);
102 dev_type_poll(vc_nb_poll);
103 dev_type_kqfilter(vc_nb_kqfilter);
104 
105 const struct cdevsw vcoda_cdevsw = {
106 	.d_open = vc_nb_open,
107 	.d_close = vc_nb_close,
108 	.d_read = vc_nb_read,
109 	.d_write = vc_nb_write,
110 	.d_ioctl = vc_nb_ioctl,
111 	.d_stop = nostop,
112 	.d_tty = notty,
113 	.d_poll = vc_nb_poll,
114 	.d_mmap = nommap,
115 	.d_kqfilter = vc_nb_kqfilter,
116 	.d_discard = nodiscard,
117 	.d_flag = D_OTHER,
118 };
119 
120 struct vmsg {
121     TAILQ_ENTRY(vmsg) vm_chain;
122     void *	 vm_data;
123     u_short	 vm_flags;
124     u_short      vm_inSize;	/* Size is at most 5000 bytes */
125     u_short	 vm_outSize;
126     u_short	 vm_opcode; 	/* copied from data to save ptr lookup */
127     int		 vm_unique;
128     void *	 vm_sleep;	/* Not used by Mach. */
129 };
130 
131 struct coda_mntinfo coda_mnttbl[NVCODA];
132 
133 #define	VM_READ	    1
134 #define	VM_WRITE    2
135 #define	VM_INTR	    4
136 
137 /* vcodaattach: do nothing */
138 void
139 vcodaattach(int n)
140 {
141 }
142 
143 /*
144  * These functions are written for NetBSD.
145  */
146 int
147 vc_nb_open(dev_t dev, int flag, int mode,
148     struct lwp *l)
149 {
150     struct vcomm *vcp;
151 
152     ENTRY;
153 
154     if (minor(dev) >= NVCODA)
155 	return(ENXIO);
156 
157     if (!coda_nc_initialized)
158 	coda_nc_init();
159 
160     vcp = &coda_mnttbl[minor(dev)].mi_vcomm;
161     if (VC_OPEN(vcp))
162 	return(EBUSY);
163 
164     selinit(&vcp->vc_selproc);
165     TAILQ_INIT(&vcp->vc_requests);
166     TAILQ_INIT(&vcp->vc_replies);
167     MARK_VC_OPEN(vcp);
168 
169     coda_mnttbl[minor(dev)].mi_vfsp = NULL;
170     coda_mnttbl[minor(dev)].mi_rootvp = NULL;
171 
172     return(0);
173 }
174 
175 int
176 vc_nb_close(dev_t dev, int flag, int mode, struct lwp *l)
177 {
178     struct vcomm *vcp;
179     struct vmsg *vmp;
180     struct coda_mntinfo *mi;
181     int                 err;
182 
183     ENTRY;
184 
185     if (minor(dev) >= NVCODA)
186 	return(ENXIO);
187 
188     mi = &coda_mnttbl[minor(dev)];
189     vcp = &(mi->mi_vcomm);
190 
191     if (!VC_OPEN(vcp))
192 	panic("vcclose: not open");
193 
194     /* prevent future operations on this vfs from succeeding by auto-
195      * unmounting any vfs mounted via this device. This frees user or
196      * sysadm from having to remember where all mount points are located.
197      * Put this before WAKEUPs to avoid queuing new messages between
198      * the WAKEUP and the unmount (which can happen if we're unlucky)
199      */
200     if (!mi->mi_rootvp) {
201 	/* just a simple open/close w no mount */
202 	MARK_VC_CLOSED(vcp);
203 	return 0;
204     }
205 
206     /* Let unmount know this is for real */
207     VTOC(mi->mi_rootvp)->c_flags |= C_UNMOUNTING;
208     coda_unmounting(mi->mi_vfsp);
209 
210     /* Wakeup clients so they can return. */
211     while ((vmp = TAILQ_FIRST(&vcp->vc_requests)) != NULL) {
212 	TAILQ_REMOVE(&vcp->vc_requests, vmp, vm_chain);
213 
214 	/* Free signal request messages and don't wakeup cause
215 	   no one is waiting. */
216 	if (vmp->vm_opcode == CODA_SIGNAL) {
217 	    CODA_FREE(vmp->vm_data, VC_IN_NO_DATA);
218 	    CODA_FREE(vmp, sizeof(struct vmsg));
219 	    continue;
220 	}
221 	outstanding_upcalls++;
222 	wakeup(&vmp->vm_sleep);
223     }
224 
225     while ((vmp = TAILQ_FIRST(&vcp->vc_replies)) != NULL) {
226 	TAILQ_REMOVE(&vcp->vc_replies, vmp, vm_chain);
227 
228 	outstanding_upcalls++;
229 	wakeup(&vmp->vm_sleep);
230     }
231 
232     MARK_VC_CLOSED(vcp);
233 
234     if (outstanding_upcalls) {
235 #ifdef	CODA_VERBOSE
236 	printf("presleep: outstanding_upcalls = %d\n", outstanding_upcalls);
237     	(void) tsleep(&outstanding_upcalls, coda_call_sleep, "coda_umount", 0);
238 	printf("postsleep: outstanding_upcalls = %d\n", outstanding_upcalls);
239 #else
240     	(void) tsleep(&outstanding_upcalls, coda_call_sleep, "coda_umount", 0);
241 #endif
242     }
243 
244     err = dounmount(mi->mi_vfsp, flag, l);
245     if (err)
246 	myprintf(("Error %d unmounting vfs in vcclose(%llu)\n",
247 	           err, (unsigned long long)minor(dev)));
248     seldestroy(&vcp->vc_selproc);
249     return 0;
250 }
251 
252 int
253 vc_nb_read(dev_t dev, struct uio *uiop, int flag)
254 {
255     struct vcomm *	vcp;
256     struct vmsg *vmp;
257     int error = 0;
258 
259     ENTRY;
260 
261     if (minor(dev) >= NVCODA)
262 	return(ENXIO);
263 
264     vcp = &coda_mnttbl[minor(dev)].mi_vcomm;
265 
266     /* Get message at head of request queue. */
267     vmp = TAILQ_FIRST(&vcp->vc_requests);
268     if (vmp == NULL)
269 	return(0);	/* Nothing to read */
270 
271     /* Move the input args into userspace */
272     uiop->uio_rw = UIO_READ;
273     error = uiomove(vmp->vm_data, vmp->vm_inSize, uiop);
274     if (error) {
275 	myprintf(("vcread: error (%d) on uiomove\n", error));
276 	error = EINVAL;
277     }
278 
279     TAILQ_REMOVE(&vcp->vc_requests, vmp, vm_chain);
280 
281     /* If request was a signal, free up the message and don't
282        enqueue it in the reply queue. */
283     if (vmp->vm_opcode == CODA_SIGNAL) {
284 	if (codadebug)
285 	    myprintf(("vcread: signal msg (%d, %d)\n",
286 		      vmp->vm_opcode, vmp->vm_unique));
287 	CODA_FREE(vmp->vm_data, VC_IN_NO_DATA);
288 	CODA_FREE(vmp, sizeof(struct vmsg));
289 	return(error);
290     }
291 
292     vmp->vm_flags |= VM_READ;
293     TAILQ_INSERT_TAIL(&vcp->vc_replies, vmp, vm_chain);
294 
295     return(error);
296 }
297 
298 int
299 vc_nb_write(dev_t dev, struct uio *uiop, int flag)
300 {
301     struct vcomm *	vcp;
302     struct vmsg *vmp;
303     struct coda_out_hdr *out;
304     u_long seq;
305     u_long opcode;
306     int tbuf[2];
307     int error = 0;
308 
309     ENTRY;
310 
311     if (minor(dev) >= NVCODA)
312 	return(ENXIO);
313 
314     vcp = &coda_mnttbl[minor(dev)].mi_vcomm;
315 
316     /* Peek at the opcode, unique without transfering the data. */
317     uiop->uio_rw = UIO_WRITE;
318     error = uiomove(tbuf, sizeof(int) * 2, uiop);
319     if (error) {
320 	myprintf(("vcwrite: error (%d) on uiomove\n", error));
321 	return(EINVAL);
322     }
323 
324     opcode = tbuf[0];
325     seq = tbuf[1];
326 
327     if (codadebug)
328 	myprintf(("vcwrite got a call for %ld.%ld\n", opcode, seq));
329 
330     if (DOWNCALL(opcode)) {
331 	union outputArgs pbuf;
332 
333 	/* get the rest of the data. */
334 	uiop->uio_rw = UIO_WRITE;
335 	error = uiomove(&pbuf.coda_purgeuser.oh.result, sizeof(pbuf) - (sizeof(int)*2), uiop);
336 	if (error) {
337 	    myprintf(("vcwrite: error (%d) on uiomove (Op %ld seq %ld)\n",
338 		      error, opcode, seq));
339 	    return(EINVAL);
340 	    }
341 
342 	return handleDownCall(opcode, &pbuf);
343     }
344 
345     /* Look for the message on the (waiting for) reply queue. */
346     TAILQ_FOREACH(vmp, &vcp->vc_replies, vm_chain) {
347 	if (vmp->vm_unique == seq) break;
348     }
349 
350     if (vmp == NULL) {
351 	if (codadebug)
352 	    myprintf(("vcwrite: msg (%ld, %ld) not found\n", opcode, seq));
353 
354 	return(ESRCH);
355     }
356 
357     /* Remove the message from the reply queue */
358     TAILQ_REMOVE(&vcp->vc_replies, vmp, vm_chain);
359 
360     /* move data into response buffer. */
361     out = (struct coda_out_hdr *)vmp->vm_data;
362     /* Don't need to copy opcode and uniquifier. */
363 
364     /* get the rest of the data. */
365     if (vmp->vm_outSize < uiop->uio_resid) {
366 	myprintf(("vcwrite: more data than asked for (%d < %lu)\n",
367 		  vmp->vm_outSize, (unsigned long) uiop->uio_resid));
368 	wakeup(&vmp->vm_sleep); 	/* Notify caller of the error. */
369 	return(EINVAL);
370     }
371 
372     tbuf[0] = uiop->uio_resid; 	/* Save this value. */
373     uiop->uio_rw = UIO_WRITE;
374     error = uiomove(&out->result, vmp->vm_outSize - (sizeof(int) * 2), uiop);
375     if (error) {
376 	myprintf(("vcwrite: error (%d) on uiomove (op %ld seq %ld)\n",
377 		  error, opcode, seq));
378 	return(EINVAL);
379     }
380 
381     /* I don't think these are used, but just in case. */
382     /* XXX - aren't these two already correct? -bnoble */
383     out->opcode = opcode;
384     out->unique = seq;
385     vmp->vm_outSize	= tbuf[0];	/* Amount of data transferred? */
386     vmp->vm_flags |= VM_WRITE;
387     wakeup(&vmp->vm_sleep);
388 
389     return(0);
390 }
391 
392 int
393 vc_nb_ioctl(dev_t dev, u_long cmd, void *addr, int flag,
394     struct lwp *l)
395 {
396     ENTRY;
397 
398     switch (cmd) {
399     case CODARESIZE: {
400 	struct coda_resize *data = (struct coda_resize *)addr;
401 	return(coda_nc_resize(data->hashsize, data->heapsize, IS_DOWNCALL));
402 	break;
403     }
404     case CODASTATS:
405 	if (coda_nc_use) {
406 	    coda_nc_gather_stats();
407 	    return(0);
408 	} else {
409 	    return(ENODEV);
410 	}
411 	break;
412     case CODAPRINT:
413 	if (coda_nc_use) {
414 	    print_coda_nc();
415 	    return(0);
416 	} else {
417 	    return(ENODEV);
418 	}
419 	break;
420     case CIOC_KERNEL_VERSION:
421 	switch (*(u_int *)addr) {
422 	case 0:
423 		*(u_int *)addr = coda_kernel_version;
424 		return 0;
425 		break;
426 	case 1:
427 	case 2:
428 		if (coda_kernel_version != *(u_int *)addr)
429 		    return ENOENT;
430 		else
431 		    return 0;
432 	default:
433 		return ENOENT;
434 	}
435     	break;
436     default :
437 	return(EINVAL);
438 	break;
439     }
440 }
441 
442 int
443 vc_nb_poll(dev_t dev, int events, struct lwp *l)
444 {
445     struct vcomm *vcp;
446     int event_msk = 0;
447 
448     ENTRY;
449 
450     if (minor(dev) >= NVCODA)
451 	return(ENXIO);
452 
453     vcp = &coda_mnttbl[minor(dev)].mi_vcomm;
454 
455     event_msk = events & (POLLIN|POLLRDNORM);
456     if (!event_msk)
457 	return(0);
458 
459     if (!TAILQ_EMPTY(&vcp->vc_requests))
460 	return(events & (POLLIN|POLLRDNORM));
461 
462     selrecord(l, &(vcp->vc_selproc));
463 
464     return(0);
465 }
466 
467 static void
468 filt_vc_nb_detach(struct knote *kn)
469 {
470 	struct vcomm *vcp = kn->kn_hook;
471 
472 	SLIST_REMOVE(&vcp->vc_selproc.sel_klist, kn, knote, kn_selnext);
473 }
474 
475 static int
476 filt_vc_nb_read(struct knote *kn, long hint)
477 {
478 	struct vcomm *vcp = kn->kn_hook;
479 	struct vmsg *vmp;
480 
481 	vmp = TAILQ_FIRST(&vcp->vc_requests);
482 	if (vmp == NULL)
483 		return (0);
484 
485 	kn->kn_data = vmp->vm_inSize;
486 	return (1);
487 }
488 
489 static const struct filterops vc_nb_read_filtops = {
490 	.f_isfd = 1,
491 	.f_attach = NULL,
492 	.f_detach = filt_vc_nb_detach,
493 	.f_event = filt_vc_nb_read,
494 };
495 
496 int
497 vc_nb_kqfilter(dev_t dev, struct knote *kn)
498 {
499 	struct vcomm *vcp;
500 	struct klist *klist;
501 
502 	ENTRY;
503 
504 	if (minor(dev) >= NVCODA)
505 		return(ENXIO);
506 
507 	vcp = &coda_mnttbl[minor(dev)].mi_vcomm;
508 
509 	switch (kn->kn_filter) {
510 	case EVFILT_READ:
511 		klist = &vcp->vc_selproc.sel_klist;
512 		kn->kn_fop = &vc_nb_read_filtops;
513 		break;
514 
515 	default:
516 		return (EINVAL);
517 	}
518 
519 	kn->kn_hook = vcp;
520 
521 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
522 
523 	return (0);
524 }
525 
526 /*
527  * Statistics
528  */
529 struct coda_clstat coda_clstat;
530 
531 /*
532  * Key question: whether to sleep interruptably or uninterruptably when
533  * waiting for Venus.  The former seems better (cause you can ^C a
534  * job), but then GNU-EMACS completion breaks. Use tsleep with no
535  * timeout, and no longjmp happens. But, when sleeping
536  * "uninterruptibly", we don't get told if it returns abnormally
537  * (e.g. kill -9).
538  */
539 
540 int
541 coda_call(struct coda_mntinfo *mntinfo, int inSize, int *outSize,
542 	void *buffer)
543 {
544 	struct vcomm *vcp;
545 	struct vmsg *vmp;
546 	int error;
547 #ifdef	CTL_C
548 	struct lwp *l = curlwp;
549 	struct proc *p = l->l_proc;
550 	sigset_t psig_omask;
551 	int i;
552 	psig_omask = l->l_sigmask;	/* XXXSA */
553 #endif
554 	if (mntinfo == NULL) {
555 	    /* Unlikely, but could be a race condition with a dying warden */
556 	    return ENODEV;
557 	}
558 
559 	vcp = &(mntinfo->mi_vcomm);
560 
561 	coda_clstat.ncalls++;
562 	coda_clstat.reqs[((struct coda_in_hdr *)buffer)->opcode]++;
563 
564 	if (!VC_OPEN(vcp))
565 	    return(ENODEV);
566 
567 	CODA_ALLOC(vmp,struct vmsg *,sizeof(struct vmsg));
568 	/* Format the request message. */
569 	vmp->vm_data = buffer;
570 	vmp->vm_flags = 0;
571 	vmp->vm_inSize = inSize;
572 	vmp->vm_outSize
573 	    = *outSize ? *outSize : inSize; /* |buffer| >= inSize */
574 	vmp->vm_opcode = ((struct coda_in_hdr *)buffer)->opcode;
575 	vmp->vm_unique = ++vcp->vc_seq;
576 	if (codadebug)
577 	    myprintf(("Doing a call for %d.%d\n",
578 		      vmp->vm_opcode, vmp->vm_unique));
579 
580 	/* Fill in the common input args. */
581 	((struct coda_in_hdr *)buffer)->unique = vmp->vm_unique;
582 
583 	/* Append msg to request queue and poke Venus. */
584 	TAILQ_INSERT_TAIL(&vcp->vc_requests, vmp, vm_chain);
585 	selnotify(&(vcp->vc_selproc), 0, 0);
586 
587 	/* We can be interrupted while we wait for Venus to process
588 	 * our request.  If the interrupt occurs before Venus has read
589 	 * the request, we dequeue and return. If it occurs after the
590 	 * read but before the reply, we dequeue, send a signal
591 	 * message, and return. If it occurs after the reply we ignore
592 	 * it. In no case do we want to restart the syscall.  If it
593 	 * was interrupted by a venus shutdown (vcclose), return
594 	 * ENODEV.  */
595 
596 	/* Ignore return, We have to check anyway */
597 #ifdef	CTL_C
598 	/* This is work in progress.  Setting coda_pcatch lets tsleep reawaken
599 	   on a ^c or ^z.  The problem is that emacs sets certain interrupts
600 	   as SA_RESTART.  This means that we should exit sleep handle the
601 	   "signal" and then go to sleep again.  Mostly this is done by letting
602 	   the syscall complete and be restarted.  We are not idempotent and
603 	   can not do this.  A better solution is necessary.
604 	 */
605 	i = 0;
606 	do {
607 	    error = tsleep(&vmp->vm_sleep, (coda_call_sleep|coda_pcatch), "coda_call", hz*2);
608 	    if (error == 0)
609 	    	break;
610 	    mutex_enter(p->p_lock);
611 	    if (error == EWOULDBLOCK) {
612 #ifdef	CODA_VERBOSE
613 		    printf("coda_call: tsleep TIMEOUT %d sec\n", 2+2*i);
614 #endif
615     	    } else if (sigispending(l, SIGIO)) {
616 		    sigaddset(&l->l_sigmask, SIGIO);
617 #ifdef	CODA_VERBOSE
618 		    printf("coda_call: tsleep returns %d SIGIO, cnt %d\n", error, i);
619 #endif
620     	    } else if (sigispending(l, SIGALRM)) {
621 		    sigaddset(&l->l_sigmask, SIGALRM);
622 #ifdef	CODA_VERBOSE
623 		    printf("coda_call: tsleep returns %d SIGALRM, cnt %d\n", error, i);
624 #endif
625 	    } else {
626 		    sigset_t tmp;
627 		    tmp = p->p_sigpend.sp_set;	/* array assignment */
628 		    sigminusset(&l->l_sigmask, &tmp);
629 
630 #ifdef	CODA_VERBOSE
631 		    printf("coda_call: tsleep returns %d, cnt %d\n", error, i);
632 		    printf("coda_call: siglist = %x.%x.%x.%x, sigmask = %x.%x.%x.%x, mask %x.%x.%x.%x\n",
633 			    p->p_sigpend.sp_set.__bits[0], p->p_sigpend.sp_set.__bits[1],
634 			    p->p_sigpend.sp_set.__bits[2], p->p_sigpend.sp_set.__bits[3],
635 			    l->l_sigmask.__bits[0], l->l_sigmask.__bits[1],
636 			    l->l_sigmask.__bits[2], l->l_sigmask.__bits[3],
637 			    tmp.__bits[0], tmp.__bits[1], tmp.__bits[2], tmp.__bits[3]);
638 #endif
639 		    mutex_exit(p->p_lock);
640 		    break;
641 #ifdef	notyet
642 		    sigminusset(&l->l_sigmask, &p->p_sigpend.sp_set);
643 		    printf("coda_call: siglist = %x.%x.%x.%x, sigmask = %x.%x.%x.%x\n",
644 			    p->p_sigpend.sp_set.__bits[0], p->p_sigpend.sp_set.__bits[1],
645 			    p->p_sigpend.sp_set.__bits[2], p->p_sigpend.sp_set.__bits[3],
646 			    l->l_sigmask.__bits[0], l->l_sigmask.__bits[1],
647 			    l->l_sigmask.__bits[2], l->l_sigmask.__bits[3]);
648 #endif
649 	    }
650 	    mutex_exit(p->p_lock);
651 	} while (error && i++ < 128 && VC_OPEN(vcp));
652 	l->l_sigmask = psig_omask;	/* XXXSA */
653 #else
654 	(void) tsleep(&vmp->vm_sleep, coda_call_sleep, "coda_call", 0);
655 #endif
656 	if (VC_OPEN(vcp)) {	/* Venus is still alive */
657  	/* Op went through, interrupt or not... */
658 	    if (vmp->vm_flags & VM_WRITE) {
659 		error = 0;
660 		*outSize = vmp->vm_outSize;
661 	    }
662 
663 	    else if (!(vmp->vm_flags & VM_READ)) {
664 		/* Interrupted before venus read it. */
665 #ifdef	CODA_VERBOSE
666 		if (1)
667 #else
668 		if (codadebug)
669 #endif
670 		    myprintf(("interrupted before read: op = %d.%d, flags = %x\n",
671 			   vmp->vm_opcode, vmp->vm_unique, vmp->vm_flags));
672 
673 		TAILQ_REMOVE(&vcp->vc_requests, vmp, vm_chain);
674 		error = EINTR;
675 	    }
676 
677 	    else {
678 		/* (!(vmp->vm_flags & VM_WRITE)) means interrupted after
679                    upcall started */
680 		/* Interrupted after start of upcall, send venus a signal */
681 		struct coda_in_hdr *dog;
682 		struct vmsg *svmp;
683 
684 #ifdef	CODA_VERBOSE
685 		if (1)
686 #else
687 		if (codadebug)
688 #endif
689 		    myprintf(("Sending Venus a signal: op = %d.%d, flags = %x\n",
690 			   vmp->vm_opcode, vmp->vm_unique, vmp->vm_flags));
691 
692 		TAILQ_REMOVE(&vcp->vc_replies, vmp, vm_chain);
693 		error = EINTR;
694 
695 		CODA_ALLOC(svmp, struct vmsg *, sizeof (struct vmsg));
696 
697 		CODA_ALLOC((svmp->vm_data), char *, sizeof (struct coda_in_hdr));
698 		dog = (struct coda_in_hdr *)svmp->vm_data;
699 
700 		svmp->vm_flags = 0;
701 		dog->opcode = svmp->vm_opcode = CODA_SIGNAL;
702 		dog->unique = svmp->vm_unique = vmp->vm_unique;
703 		svmp->vm_inSize = sizeof (struct coda_in_hdr);
704 /*??? rvb */	svmp->vm_outSize = sizeof (struct coda_in_hdr);
705 
706 		if (codadebug)
707 		    myprintf(("coda_call: enqueing signal msg (%d, %d)\n",
708 			   svmp->vm_opcode, svmp->vm_unique));
709 
710 		/* insert at head of queue */
711 		TAILQ_INSERT_HEAD(&vcp->vc_requests, svmp, vm_chain);
712 		selnotify(&(vcp->vc_selproc), 0, 0);
713 	    }
714 	}
715 
716 	else {	/* If venus died (!VC_OPEN(vcp)) */
717 	    if (codadebug)
718 		myprintf(("vcclose woke op %d.%d flags %d\n",
719 		       vmp->vm_opcode, vmp->vm_unique, vmp->vm_flags));
720 
721 		error = ENODEV;
722 	}
723 
724 	CODA_FREE(vmp, sizeof(struct vmsg));
725 
726 	if (outstanding_upcalls > 0 && (--outstanding_upcalls == 0))
727 		wakeup(&outstanding_upcalls);
728 
729 	if (!error)
730 		error = ((struct coda_out_hdr *)buffer)->result;
731 	return(error);
732 }
733 
734 MODULE(MODULE_CLASS_DRIVER, vcoda, NULL);
735 
736 static int
737 vcoda_modcmd(modcmd_t cmd, void *arg)
738 {
739 	int error = 0;
740 
741 	switch (cmd) {
742 	case MODULE_CMD_INIT:
743 #ifdef _MODULE
744 	{
745 		int cmajor, dmajor;
746 		vcodaattach(NVCODA);
747 
748 		dmajor = cmajor = -1;
749 		return devsw_attach("vcoda", NULL, &dmajor,
750 		    &vcoda_cdevsw, &cmajor);
751 	}
752 #endif
753 		break;
754 
755 	case MODULE_CMD_FINI:
756 #ifdef _MODULE
757 		{
758 			for  (size_t i = 0; i < NVCODA; i++) {
759 				struct vcomm *vcp = &coda_mnttbl[i].mi_vcomm;
760 				if (VC_OPEN(vcp))
761 					return EBUSY;
762 			}
763 			return devsw_detach(NULL, &vcoda_cdevsw);
764 		}
765 #endif
766 		break;
767 
768 	case MODULE_CMD_STAT:
769 		return ENOTTY;
770 
771 	default:
772 		return ENOTTY;
773 	}
774 	return error;
775 }
776