xref: /onnv-gate/usr/src/uts/common/io/cons.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 1987-2003 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate /*
30*0Sstevel@tonic-gate  * Indirect console driver for Sun.
31*0Sstevel@tonic-gate  *
32*0Sstevel@tonic-gate  * Redirects all I/O to the device designated as the underlying "hardware"
33*0Sstevel@tonic-gate  * console, as given by the value of rconsvp.  The implementation assumes that
34*0Sstevel@tonic-gate  * rconsvp denotes a STREAMS device; the assumption is justified since
35*0Sstevel@tonic-gate  * consoles must be capable of effecting tty semantics.
36*0Sstevel@tonic-gate  *
37*0Sstevel@tonic-gate  * rconsvp is set in autoconf.c:consconfig(), based on information obtained
38*0Sstevel@tonic-gate  * from the EEPROM.
39*0Sstevel@tonic-gate  *
40*0Sstevel@tonic-gate  * XXX:	The driver still needs to be converted to use ANSI C consistently
41*0Sstevel@tonic-gate  *	throughout.
42*0Sstevel@tonic-gate  */
43*0Sstevel@tonic-gate 
44*0Sstevel@tonic-gate #include <sys/types.h>
45*0Sstevel@tonic-gate #include <sys/open.h>
46*0Sstevel@tonic-gate #include <sys/param.h>
47*0Sstevel@tonic-gate #include <sys/systm.h>
48*0Sstevel@tonic-gate #include <sys/signal.h>
49*0Sstevel@tonic-gate #include <sys/cred.h>
50*0Sstevel@tonic-gate #include <sys/user.h>
51*0Sstevel@tonic-gate #include <sys/proc.h>
52*0Sstevel@tonic-gate #include <sys/disp.h>
53*0Sstevel@tonic-gate #include <sys/file.h>
54*0Sstevel@tonic-gate #include <sys/taskq.h>
55*0Sstevel@tonic-gate #include <sys/log.h>
56*0Sstevel@tonic-gate #include <sys/vnode.h>
57*0Sstevel@tonic-gate #include <sys/uio.h>
58*0Sstevel@tonic-gate #include <sys/stat.h>
59*0Sstevel@tonic-gate 
60*0Sstevel@tonic-gate #include <sys/console.h>
61*0Sstevel@tonic-gate #include <sys/consdev.h>
62*0Sstevel@tonic-gate 
63*0Sstevel@tonic-gate #include <sys/stream.h>
64*0Sstevel@tonic-gate #include <sys/strsubr.h>
65*0Sstevel@tonic-gate #include <sys/poll.h>
66*0Sstevel@tonic-gate 
67*0Sstevel@tonic-gate #include <sys/debug.h>
68*0Sstevel@tonic-gate 
69*0Sstevel@tonic-gate #include <sys/conf.h>
70*0Sstevel@tonic-gate #include <sys/ddi.h>
71*0Sstevel@tonic-gate #include <sys/sunddi.h>
72*0Sstevel@tonic-gate 
73*0Sstevel@tonic-gate static int cnopen(dev_t *, int, int, struct cred *);
74*0Sstevel@tonic-gate static int cnclose(dev_t, int, int, struct cred *);
75*0Sstevel@tonic-gate static int cnread(dev_t, struct uio *, struct cred *);
76*0Sstevel@tonic-gate static int cnwrite(dev_t, struct uio *, struct cred *);
77*0Sstevel@tonic-gate static int cnioctl(dev_t, int, intptr_t, int, struct cred *, int *);
78*0Sstevel@tonic-gate static int cnpoll(dev_t, short, int, short *, struct pollhead **);
79*0Sstevel@tonic-gate static int cn_info(dev_info_t *, ddi_info_cmd_t, void *, void **);
80*0Sstevel@tonic-gate static int cn_attach(dev_info_t *, ddi_attach_cmd_t);
81*0Sstevel@tonic-gate static int cn_detach(dev_info_t *, ddi_detach_cmd_t);
82*0Sstevel@tonic-gate 
83*0Sstevel@tonic-gate static dev_info_t *cn_dip;		/* private copy of devinfo pointer */
84*0Sstevel@tonic-gate 
85*0Sstevel@tonic-gate static struct cb_ops cn_cb_ops = {
86*0Sstevel@tonic-gate 
87*0Sstevel@tonic-gate 	cnopen,			/* open */
88*0Sstevel@tonic-gate 	cnclose,		/* close */
89*0Sstevel@tonic-gate 	nodev,			/* strategy */
90*0Sstevel@tonic-gate 	nodev,			/* print */
91*0Sstevel@tonic-gate 	nodev,			/* dump */
92*0Sstevel@tonic-gate 	cnread,			/* read */
93*0Sstevel@tonic-gate 	cnwrite,		/* write */
94*0Sstevel@tonic-gate 	cnioctl,		/* ioctl */
95*0Sstevel@tonic-gate 	nodev,			/* devmap */
96*0Sstevel@tonic-gate 	nodev,			/* mmap */
97*0Sstevel@tonic-gate 	nodev, 			/* segmap */
98*0Sstevel@tonic-gate 	cnpoll,			/* poll */
99*0Sstevel@tonic-gate 	ddi_prop_op,		/* cb_prop_op */
100*0Sstevel@tonic-gate 	0,			/* streamtab  */
101*0Sstevel@tonic-gate 	D_NEW | D_MP		/* Driver compatibility flag */
102*0Sstevel@tonic-gate 
103*0Sstevel@tonic-gate };
104*0Sstevel@tonic-gate 
105*0Sstevel@tonic-gate static struct dev_ops cn_ops = {
106*0Sstevel@tonic-gate 
107*0Sstevel@tonic-gate 	DEVO_REV,		/* devo_rev, */
108*0Sstevel@tonic-gate 	0,			/* refcnt  */
109*0Sstevel@tonic-gate 	cn_info,		/* info */
110*0Sstevel@tonic-gate 	nulldev,		/* identify */
111*0Sstevel@tonic-gate 	nulldev,		/* probe */
112*0Sstevel@tonic-gate 	cn_attach,		/* attach */
113*0Sstevel@tonic-gate 	cn_detach,		/* detach */
114*0Sstevel@tonic-gate 	nodev,			/* reset */
115*0Sstevel@tonic-gate 	&cn_cb_ops,		/* driver operations */
116*0Sstevel@tonic-gate 	(struct bus_ops *)0	/* bus operations */
117*0Sstevel@tonic-gate 
118*0Sstevel@tonic-gate };
119*0Sstevel@tonic-gate 
120*0Sstevel@tonic-gate /*
121*0Sstevel@tonic-gate  * Global variables associated with the console device:
122*0Sstevel@tonic-gate  *
123*0Sstevel@tonic-gate  * XXX:	There are too many of these!
124*0Sstevel@tonic-gate  * moved to space.c to becone resident in the kernel so that cons
125*0Sstevel@tonic-gate  * can be loadable.
126*0Sstevel@tonic-gate  */
127*0Sstevel@tonic-gate 
128*0Sstevel@tonic-gate extern dev_t	rconsdev;	/* "hardware" console */
129*0Sstevel@tonic-gate extern vnode_t	*rconsvp;	/* pointer to vnode for that device */
130*0Sstevel@tonic-gate 
131*0Sstevel@tonic-gate /*
132*0Sstevel@tonic-gate  * XXX: consulted in prsubr.c, for /proc entry point for obtaining ps info.
133*0Sstevel@tonic-gate  */
134*0Sstevel@tonic-gate extern dev_t	uconsdev;	/* What the user thinks is the console device */
135*0Sstevel@tonic-gate 
136*0Sstevel@tonic-gate /*
137*0Sstevel@tonic-gate  * Private driver state:
138*0Sstevel@tonic-gate  */
139*0Sstevel@tonic-gate 
140*0Sstevel@tonic-gate /*
141*0Sstevel@tonic-gate  * The underlying console device potentially can be opened through (at least)
142*0Sstevel@tonic-gate  * two paths: through this driver and through the underlying device's driver.
143*0Sstevel@tonic-gate  * To ensure that reference counts are meaningful and therefore that close
144*0Sstevel@tonic-gate  * routines are called at the right time, it's important to make sure that
145*0Sstevel@tonic-gate  * rconsvp's s_count field (i.e., the count on the underlying device) never
146*0Sstevel@tonic-gate  * has a contribution of more than one through this driver, regardless of how
147*0Sstevel@tonic-gate  * many times this driver's been opened.  rconsopen keeps track of the
148*0Sstevel@tonic-gate  * necessary information to ensure this property.
149*0Sstevel@tonic-gate  */
150*0Sstevel@tonic-gate static uint_t	rconsopen;
151*0Sstevel@tonic-gate 
152*0Sstevel@tonic-gate 
153*0Sstevel@tonic-gate #include <sys/types.h>
154*0Sstevel@tonic-gate #include <sys/conf.h>
155*0Sstevel@tonic-gate #include <sys/param.h>
156*0Sstevel@tonic-gate #include <sys/systm.h>
157*0Sstevel@tonic-gate #include <sys/errno.h>
158*0Sstevel@tonic-gate #include <sys/modctl.h>
159*0Sstevel@tonic-gate 
160*0Sstevel@tonic-gate 
161*0Sstevel@tonic-gate extern int nodev(), nulldev();
162*0Sstevel@tonic-gate extern int dseekneg_flag;
163*0Sstevel@tonic-gate extern struct mod_ops mod_driverops;
164*0Sstevel@tonic-gate extern struct dev_ops cn_ops;
165*0Sstevel@tonic-gate 
166*0Sstevel@tonic-gate /*
167*0Sstevel@tonic-gate  * Module linkage information for the kernel.
168*0Sstevel@tonic-gate  */
169*0Sstevel@tonic-gate 
170*0Sstevel@tonic-gate static struct modldrv modldrv = {
171*0Sstevel@tonic-gate 	&mod_driverops, /* Type of module.  This one is a pseudo driver */
172*0Sstevel@tonic-gate 	"Console redirection driver %I%",
173*0Sstevel@tonic-gate 	&cn_ops,	/* driver ops */
174*0Sstevel@tonic-gate };
175*0Sstevel@tonic-gate 
176*0Sstevel@tonic-gate static struct modlinkage modlinkage = {
177*0Sstevel@tonic-gate 	MODREV_1,
178*0Sstevel@tonic-gate 	&modldrv,
179*0Sstevel@tonic-gate 	NULL
180*0Sstevel@tonic-gate };
181*0Sstevel@tonic-gate 
182*0Sstevel@tonic-gate int
183*0Sstevel@tonic-gate _init(void)
184*0Sstevel@tonic-gate {
185*0Sstevel@tonic-gate 	return (mod_install(&modlinkage));
186*0Sstevel@tonic-gate }
187*0Sstevel@tonic-gate 
188*0Sstevel@tonic-gate int
189*0Sstevel@tonic-gate _fini(void)
190*0Sstevel@tonic-gate {
191*0Sstevel@tonic-gate 	return (EBUSY);
192*0Sstevel@tonic-gate }
193*0Sstevel@tonic-gate 
194*0Sstevel@tonic-gate int
195*0Sstevel@tonic-gate _info(struct modinfo *modinfop)
196*0Sstevel@tonic-gate {
197*0Sstevel@tonic-gate 	return (mod_info(&modlinkage, modinfop));
198*0Sstevel@tonic-gate }
199*0Sstevel@tonic-gate 
200*0Sstevel@tonic-gate /*
201*0Sstevel@tonic-gate  * DDI glue routines
202*0Sstevel@tonic-gate  */
203*0Sstevel@tonic-gate static int
204*0Sstevel@tonic-gate cn_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
205*0Sstevel@tonic-gate {
206*0Sstevel@tonic-gate 	if (cmd != DDI_ATTACH)
207*0Sstevel@tonic-gate 		return (DDI_FAILURE);
208*0Sstevel@tonic-gate 
209*0Sstevel@tonic-gate 	if (ddi_create_minor_node(devi, "syscon", S_IFCHR,
210*0Sstevel@tonic-gate 	    0, DDI_PSEUDO, NULL) == DDI_FAILURE) {
211*0Sstevel@tonic-gate 		return (DDI_FAILURE);
212*0Sstevel@tonic-gate 	}
213*0Sstevel@tonic-gate 	if (ddi_create_minor_node(devi, "systty", S_IFCHR,
214*0Sstevel@tonic-gate 	    0, DDI_PSEUDO, NULL) == DDI_FAILURE) {
215*0Sstevel@tonic-gate 		ddi_remove_minor_node(devi, NULL);
216*0Sstevel@tonic-gate 		return (DDI_FAILURE);
217*0Sstevel@tonic-gate 	}
218*0Sstevel@tonic-gate 	if (ddi_create_minor_node(devi, "console", S_IFCHR,
219*0Sstevel@tonic-gate 	    0, DDI_PSEUDO, NULL) == DDI_FAILURE) {
220*0Sstevel@tonic-gate 		ddi_remove_minor_node(devi, NULL);
221*0Sstevel@tonic-gate 		return (DDI_FAILURE);
222*0Sstevel@tonic-gate 	}
223*0Sstevel@tonic-gate 	cn_dip = devi;
224*0Sstevel@tonic-gate 	return (DDI_SUCCESS);
225*0Sstevel@tonic-gate }
226*0Sstevel@tonic-gate 
227*0Sstevel@tonic-gate static int
228*0Sstevel@tonic-gate cn_detach(dev_info_t *devi, ddi_detach_cmd_t cmd)
229*0Sstevel@tonic-gate {
230*0Sstevel@tonic-gate 	if (cmd != DDI_DETACH)
231*0Sstevel@tonic-gate 		return (DDI_FAILURE);
232*0Sstevel@tonic-gate 	ddi_remove_minor_node(devi, NULL);
233*0Sstevel@tonic-gate 	uconsdev = NODEV;
234*0Sstevel@tonic-gate 	return (DDI_SUCCESS);
235*0Sstevel@tonic-gate }
236*0Sstevel@tonic-gate 
237*0Sstevel@tonic-gate /* ARGSUSED */
238*0Sstevel@tonic-gate static int
239*0Sstevel@tonic-gate cn_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
240*0Sstevel@tonic-gate {
241*0Sstevel@tonic-gate 	int error = DDI_FAILURE;
242*0Sstevel@tonic-gate 
243*0Sstevel@tonic-gate 	switch (infocmd) {
244*0Sstevel@tonic-gate 	case DDI_INFO_DEVT2DEVINFO:
245*0Sstevel@tonic-gate 		if (getminor((dev_t)arg) == 0 && cn_dip != NULL) {
246*0Sstevel@tonic-gate 			*result = (void *) cn_dip;
247*0Sstevel@tonic-gate 			error = DDI_SUCCESS;
248*0Sstevel@tonic-gate 		}
249*0Sstevel@tonic-gate 		break;
250*0Sstevel@tonic-gate 
251*0Sstevel@tonic-gate 	case DDI_INFO_DEVT2INSTANCE:
252*0Sstevel@tonic-gate 		if (getminor((dev_t)arg) == 0) {
253*0Sstevel@tonic-gate 			*result = (void *)0;
254*0Sstevel@tonic-gate 			error = DDI_SUCCESS;
255*0Sstevel@tonic-gate 		}
256*0Sstevel@tonic-gate 		break;
257*0Sstevel@tonic-gate 
258*0Sstevel@tonic-gate 	default:
259*0Sstevel@tonic-gate 		break;
260*0Sstevel@tonic-gate 	}
261*0Sstevel@tonic-gate 
262*0Sstevel@tonic-gate 	return (error);
263*0Sstevel@tonic-gate }
264*0Sstevel@tonic-gate 
265*0Sstevel@tonic-gate /*
266*0Sstevel@tonic-gate  * XXX	Caution: before allowing more than 256 minor devices on the
267*0Sstevel@tonic-gate  *	console, make sure you understand the 'compatibility' hack
268*0Sstevel@tonic-gate  *	in ufs_iget() that translates old dev_t's to new dev_t's.
269*0Sstevel@tonic-gate  *	See bugid 1098104 for the sordid details.
270*0Sstevel@tonic-gate  */
271*0Sstevel@tonic-gate 
272*0Sstevel@tonic-gate /* ARGSUSED */
273*0Sstevel@tonic-gate static int
274*0Sstevel@tonic-gate cnopen(dev_t *dev, int flag, int state, struct cred *cred)
275*0Sstevel@tonic-gate {
276*0Sstevel@tonic-gate 	int	err;
277*0Sstevel@tonic-gate 	static int	been_here;
278*0Sstevel@tonic-gate 	vnode_t	*vp = rconsvp;
279*0Sstevel@tonic-gate 
280*0Sstevel@tonic-gate 	ASSERT(cred != NULL);
281*0Sstevel@tonic-gate 
282*0Sstevel@tonic-gate 	if (rconsvp == NULL)
283*0Sstevel@tonic-gate 		return (0);
284*0Sstevel@tonic-gate 
285*0Sstevel@tonic-gate 
286*0Sstevel@tonic-gate 	/*
287*0Sstevel@tonic-gate 	 * XXX: Clean up inactive PIDs from previous opens if any.
288*0Sstevel@tonic-gate 	 * These would have been created as a result of an I_SETSIG
289*0Sstevel@tonic-gate 	 * issued against console.  This is a workaround, and
290*0Sstevel@tonic-gate 	 * console driver must be correctly redesigned not to need
291*0Sstevel@tonic-gate 	 * this hook.
292*0Sstevel@tonic-gate 	 */
293*0Sstevel@tonic-gate 	if (vp->v_stream) {
294*0Sstevel@tonic-gate 		str_cn_clean(vp);
295*0Sstevel@tonic-gate 	}
296*0Sstevel@tonic-gate 
297*0Sstevel@tonic-gate 	/*
298*0Sstevel@tonic-gate 	 * XXX:	Set hook to tell /proc about underlying console.  (There's
299*0Sstevel@tonic-gate 	 *	gotta be a better way...)
300*0Sstevel@tonic-gate 	 */
301*0Sstevel@tonic-gate 	if (state != OTYP_CHR || getminor(*dev) != 0)
302*0Sstevel@tonic-gate 		return (ENXIO);
303*0Sstevel@tonic-gate 	if (been_here == 0) {
304*0Sstevel@tonic-gate 		uconsdev = *dev;
305*0Sstevel@tonic-gate 		been_here = 1;
306*0Sstevel@tonic-gate 		if (vn_open("/dev/console", UIO_SYSSPACE, FWRITE | FNOCTTY,
307*0Sstevel@tonic-gate 		    0, &console_vnode, 0, 0) == 0)
308*0Sstevel@tonic-gate 			console_taskq = taskq_create("console_taskq",
309*0Sstevel@tonic-gate 			    1, maxclsyspri - 1, LOG_LOWAT / LOG_MSGSIZE,
310*0Sstevel@tonic-gate 			    LOG_HIWAT / LOG_MSGSIZE, TASKQ_PREPOPULATE);
311*0Sstevel@tonic-gate 	}
312*0Sstevel@tonic-gate 
313*0Sstevel@tonic-gate 	if ((err = VOP_OPEN(&vp, flag, cred)) != 0)
314*0Sstevel@tonic-gate 		return (err);
315*0Sstevel@tonic-gate 
316*0Sstevel@tonic-gate 	/*
317*0Sstevel@tonic-gate 	 * The underlying driver is not allowed to have cloned itself
318*0Sstevel@tonic-gate 	 * for this open.
319*0Sstevel@tonic-gate 	 */
320*0Sstevel@tonic-gate 	if (vp != rconsvp) {
321*0Sstevel@tonic-gate 		/*
322*0Sstevel@tonic-gate 		 * It might happen that someone set rconsvp to NULL
323*0Sstevel@tonic-gate 		 * whilst we were in the middle of the open.
324*0Sstevel@tonic-gate 		 */
325*0Sstevel@tonic-gate 		if (rconsvp == NULL) {
326*0Sstevel@tonic-gate 			(void) VOP_CLOSE(vp, flag, 1, (offset_t)0, cred);
327*0Sstevel@tonic-gate 			return (0);
328*0Sstevel@tonic-gate 		}
329*0Sstevel@tonic-gate 		cmn_err(CE_PANIC, "cnopen: cloned open");
330*0Sstevel@tonic-gate 	}
331*0Sstevel@tonic-gate 
332*0Sstevel@tonic-gate 	rconsopen++;
333*0Sstevel@tonic-gate 
334*0Sstevel@tonic-gate 	return (0);
335*0Sstevel@tonic-gate }
336*0Sstevel@tonic-gate 
337*0Sstevel@tonic-gate /* ARGSUSED */
338*0Sstevel@tonic-gate static int
339*0Sstevel@tonic-gate cnclose(dev_t dev, int flag, int state, struct cred *cred)
340*0Sstevel@tonic-gate {
341*0Sstevel@tonic-gate 	int	err = 0;
342*0Sstevel@tonic-gate 	vnode_t	*vp;
343*0Sstevel@tonic-gate 
344*0Sstevel@tonic-gate 	/*
345*0Sstevel@tonic-gate 	 * Since this is the _last_ close, it's our last chance to close the
346*0Sstevel@tonic-gate 	 * underlying device.  (Note that if someone else has the underlying
347*0Sstevel@tonic-gate 	 * hardware console device open, we won't get here, since spec_close
348*0Sstevel@tonic-gate 	 * will see s_count > 1.)
349*0Sstevel@tonic-gate 	 */
350*0Sstevel@tonic-gate 	if (state != OTYP_CHR)
351*0Sstevel@tonic-gate 		return (ENXIO);
352*0Sstevel@tonic-gate 
353*0Sstevel@tonic-gate 	if (rconsvp == NULL)
354*0Sstevel@tonic-gate 		return (0);
355*0Sstevel@tonic-gate 
356*0Sstevel@tonic-gate 	while ((rconsopen != 0) && ((vp = rconsvp) != NULL)) {
357*0Sstevel@tonic-gate 		err = VOP_CLOSE(vp, flag, 1, (offset_t)0, cred);
358*0Sstevel@tonic-gate 		if (!err) {
359*0Sstevel@tonic-gate 			vp->v_stream = NULL;
360*0Sstevel@tonic-gate 			rconsopen--;
361*0Sstevel@tonic-gate 		}
362*0Sstevel@tonic-gate 	}
363*0Sstevel@tonic-gate 	return (err);
364*0Sstevel@tonic-gate }
365*0Sstevel@tonic-gate 
366*0Sstevel@tonic-gate /* ARGSUSED */
367*0Sstevel@tonic-gate static int
368*0Sstevel@tonic-gate cnread(dev_t dev, struct uio *uio, struct cred *cred)
369*0Sstevel@tonic-gate {
370*0Sstevel@tonic-gate 	kcondvar_t	sleep_forever;
371*0Sstevel@tonic-gate 	kmutex_t	sleep_forever_mutex;
372*0Sstevel@tonic-gate 
373*0Sstevel@tonic-gate 	if (rconsvp == NULL) {
374*0Sstevel@tonic-gate 		/*
375*0Sstevel@tonic-gate 		 * Go to sleep forever.  This seems like the least
376*0Sstevel@tonic-gate 		 * harmful thing to do if there's no console.
377*0Sstevel@tonic-gate 		 * EOF might be better if we're ending up single-user
378*0Sstevel@tonic-gate 		 * mode.
379*0Sstevel@tonic-gate 		 */
380*0Sstevel@tonic-gate 		cv_init(&sleep_forever, NULL, CV_DRIVER, NULL);
381*0Sstevel@tonic-gate 		mutex_init(&sleep_forever_mutex, NULL, MUTEX_DRIVER, NULL);
382*0Sstevel@tonic-gate 		mutex_enter(&sleep_forever_mutex);
383*0Sstevel@tonic-gate 		(void) cv_wait_sig(&sleep_forever, &sleep_forever_mutex);
384*0Sstevel@tonic-gate 		mutex_exit(&sleep_forever_mutex);
385*0Sstevel@tonic-gate 		return (EIO);
386*0Sstevel@tonic-gate 	}
387*0Sstevel@tonic-gate 
388*0Sstevel@tonic-gate 	if (rconsvp->v_stream != NULL)
389*0Sstevel@tonic-gate 		return (strread(rconsvp, uio, cred));
390*0Sstevel@tonic-gate 	else
391*0Sstevel@tonic-gate 		return (cdev_read(rconsdev, uio, cred));
392*0Sstevel@tonic-gate }
393*0Sstevel@tonic-gate 
394*0Sstevel@tonic-gate /* ARGSUSED */
395*0Sstevel@tonic-gate static int
396*0Sstevel@tonic-gate cnwrite(dev_t dev, struct uio *uio, struct cred *cred)
397*0Sstevel@tonic-gate {
398*0Sstevel@tonic-gate 	if (rconsvp == NULL) {
399*0Sstevel@tonic-gate 		uio->uio_resid = 0;
400*0Sstevel@tonic-gate 		return (0);
401*0Sstevel@tonic-gate 	}
402*0Sstevel@tonic-gate 
403*0Sstevel@tonic-gate 	if (rconsvp->v_stream != NULL)
404*0Sstevel@tonic-gate 		return (strwrite(rconsvp, uio, cred));
405*0Sstevel@tonic-gate 	else
406*0Sstevel@tonic-gate 		return (cdev_write(rconsdev, uio, cred));
407*0Sstevel@tonic-gate }
408*0Sstevel@tonic-gate 
409*0Sstevel@tonic-gate /* ARGSUSED */
410*0Sstevel@tonic-gate static int
411*0Sstevel@tonic-gate cnioctl(dev_t dev, int cmd, intptr_t arg, int flag, struct cred *cred,
412*0Sstevel@tonic-gate 	int *rvalp)
413*0Sstevel@tonic-gate {
414*0Sstevel@tonic-gate 	if (rconsvp == NULL)
415*0Sstevel@tonic-gate 		return (0);
416*0Sstevel@tonic-gate 
417*0Sstevel@tonic-gate 	if (rconsvp->v_stream != NULL)
418*0Sstevel@tonic-gate 		return (strioctl(rconsvp, cmd, arg, flag, U_TO_K, cred,
419*0Sstevel@tonic-gate 		    rvalp));
420*0Sstevel@tonic-gate 	else
421*0Sstevel@tonic-gate 		return (cdev_ioctl(rconsdev, cmd, arg, flag, cred, rvalp));
422*0Sstevel@tonic-gate }
423*0Sstevel@tonic-gate 
424*0Sstevel@tonic-gate /* ARGSUSED */
425*0Sstevel@tonic-gate static int
426*0Sstevel@tonic-gate cnpoll(dev_t dev, short events, int anyyet, short *reventsp,
427*0Sstevel@tonic-gate 	struct pollhead **phpp)
428*0Sstevel@tonic-gate {
429*0Sstevel@tonic-gate 	if (rconsvp == NULL)
430*0Sstevel@tonic-gate 		return (nochpoll(dev, events, anyyet, reventsp, phpp));
431*0Sstevel@tonic-gate 
432*0Sstevel@tonic-gate 	if (rconsvp->v_stream != NULL)
433*0Sstevel@tonic-gate 		return (strpoll(rconsvp->v_stream, events, anyyet, reventsp,
434*0Sstevel@tonic-gate 		    phpp));
435*0Sstevel@tonic-gate 	else
436*0Sstevel@tonic-gate 		return (cdev_poll(rconsdev, events, anyyet, reventsp, phpp));
437*0Sstevel@tonic-gate }
438