xref: /illumos-gate/usr/src/uts/common/io/ppp/sppp/sppp_mod.c (revision 9113a79cf228b8f7bd509b1328adf88659dfe218)
1 /*
2  * sppp_mod.c - modload support for PPP pseudo-device driver.
3  *
4  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
5  * Use is subject to license terms.
6  *
7  * Permission to use, copy, modify, and distribute this software and its
8  * documentation is hereby granted, provided that the above copyright
9  * notice appears in all copies.
10  *
11  * SUN MAKES NO REPRESENTATION OR WARRANTIES ABOUT THE SUITABILITY OF
12  * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
13  * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
14  * PARTICULAR PURPOSE, OR NON-INFRINGEMENT.  SUN SHALL NOT BE LIABLE FOR
15  * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
16  * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES
17  *
18  * Copyright (c) 1994 The Australian National University.
19  * All rights reserved.
20  *
21  * Permission to use, copy, modify, and distribute this software and its
22  * documentation is hereby granted, provided that the above copyright
23  * notice appears in all copies.  This software is provided without any
24  * warranty, express or implied. The Australian National University
25  * makes no representations about the suitability of this software for
26  * any purpose.
27  *
28  * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
29  * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
30  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
31  * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
32  * OF SUCH DAMAGE.
33  *
34  * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
35  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
36  * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
37  * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
38  * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
39  * OR MODIFICATIONS.
40  *
41  * This driver is derived from the original SVR4 STREAMS PPP driver
42  * originally written by Paul Mackerras <paul.mackerras@cs.anu.edu.au>.
43  *
44  * Adi Masputra <adi.masputra@sun.com> rewrote and restructured the code
45  * for improved performance and scalability.
46  */
47 
48 #pragma ident	"%Z%%M%	%I%	%E% SMI"
49 #define	RCSID	" $Id: sppp_mod.c,v 1.0 2000/05/08 10:53:28 masputra Exp $"
50 
51 #include <sys/types.h>
52 #include <sys/debug.h>
53 #include <sys/systm.h>
54 #include <sys/ddi.h>
55 #include <sys/strlog.h>
56 #include <sys/conf.h>
57 #include <sys/sunddi.h>
58 #include <sys/ksynch.h>
59 #include <sys/stat.h>
60 #include <sys/kstat.h>
61 #include <sys/socket.h>
62 #include <net/pppio.h>
63 #include <sys/modctl.h>
64 
65 #include "s_common.h"
66 #include "sppp.h"
67 
68 static int	_mi_driver_attach(dev_info_t *, ddi_attach_cmd_t);
69 static int	_mi_driver_detach(dev_info_t *, ddi_detach_cmd_t);
70 static int	_mi_driver_info(dev_info_t *, ddi_info_cmd_t, void *, void **);
71 
72 /*
73  * Globals for PPP multiplexer module wrapper
74  */
75 extern const char sppp_module_description[];
76 static dev_info_t *_mi_dip;
77 
78 #define	PPP_MI_HIWAT	(PPP_MTU * 16)	/* XXX find more meaningful value */
79 #define	PPP_MI_LOWAT	(PPP_MTU * 14)	/* XXX find more meaningful value */
80 
81 static struct module_info sppp_modinfo = {
82 	PPP_MOD_ID,		/* mi_idnum */
83 	PPP_DRV_NAME,		/* mi_idname */
84 	0,			/* mi_minpsz */
85 	PPP_MAXMTU,		/* mi_maxpsz */
86 	PPP_MI_HIWAT,		/* mi_hiwat */
87 	PPP_MI_LOWAT		/* mi_lowat */
88 };
89 
90 static struct qinit sppp_urinit = {
91 	NULL,			/* qi_putp */
92 	NULL,			/* qi_srvp */
93 	sppp_open,		/* qi_qopen */
94 	sppp_close,		/* qi_qclose */
95 	NULL,			/* qi_qadmin */
96 	&sppp_modinfo,		/* qi_minfo */
97 	NULL			/* qi_mstat */
98 };
99 
100 static struct qinit sppp_uwinit = {
101 	sppp_uwput,		/* qi_putp */
102 	sppp_uwsrv,		/* qi_srvp */
103 	NULL,			/* qi_qopen */
104 	NULL,			/* qi_qclose */
105 	NULL,			/* qi_qadmin */
106 	&sppp_modinfo,		/* qi_minfo */
107 	NULL			/* qi_mstat */
108 };
109 
110 static struct qinit sppp_lrinit = {
111 	sppp_lrput,		/* qi_putp */
112 	NULL,			/* qi_srvp */
113 	NULL,			/* qi_qopen */
114 	NULL,			/* qi_qclose */
115 	NULL,			/* qi_qadmin */
116 	&sppp_modinfo,		/* qi_minfo */
117 	NULL			/* qi_mstat */
118 };
119 
120 static struct qinit sppp_lwinit = {
121 	NULL,			/* qi_putp */
122 	sppp_lwsrv,		/* qi_srvp */
123 	NULL,			/* qi_qopen */
124 	NULL,			/* qi_qclose */
125 	NULL,			/* qi_qadmin */
126 	&sppp_modinfo,		/* qi_minfo */
127 	NULL			/* qi_mstat */
128 };
129 
130 static struct streamtab sppp_tab = {
131 	&sppp_urinit,		/* st_rdinit */
132 	&sppp_uwinit,		/* st_wrinit */
133 	&sppp_lrinit,		/* st_muxrinit */
134 	&sppp_lwinit		/* st_muxwrinit */
135 };
136 
137 /*
138  * Descriptions for flags values in cb_flags field:
139  *
140  * D_MTQPAIR:
141  *    An inner perimeter that spans the queue pair.
142  * D_MTOUTPERIM:
143  *    An outer perimeter that spans over all queues in the module.
144  * D_MTOCEXCL:
145  *    Open & close procedures are entered exclusively at outer perimeter.
146  * D_MTPUTSHARED:
147  *    Entry to put procedures are done with SHARED (reader) acess
148  *    and not EXCLUSIVE (writer) access.
149  *
150  * Therefore:
151  *
152  * 1. Open and close procedures are entered with EXCLUSIVE (writer)
153  *    access at the inner perimeter, and with EXCLUSIVE (writer) access at
154  *    the outer perimeter.
155  *
156  * 2. Put procedures are entered with SHARED (reader) access at the inner
157  *    perimeter, and with SHARED (reader) access at the outer perimeter.
158  *
159  * 3. Service procedures are entered with EXCLUSIVE (writer) access at
160  *    the inner perimeter, and with SHARED (reader) access at the
161  *    outer perimeter.
162  *
163  * Do not attempt to modify these flags unless the entire corresponding
164  * driver code is changed to accomodate the newly represented MT-STREAMS
165  * flags. Doing so without making proper modifications to the driver code
166  * will severely impact the intended driver behavior, and thus may affect
167  * the system's stability and performance.
168  */
169 DDI_DEFINE_STREAM_OPS(sppp_ops,						\
170 	nulldev, nulldev,						\
171 	_mi_driver_attach, _mi_driver_detach, nodev, _mi_driver_info,	\
172 	D_NEW | D_MP | D_MTQPAIR | D_MTOUTPERIM | D_MTOCEXCL | D_MTPUTSHARED, \
173 	&sppp_tab);
174 
175 static struct modldrv modldrv = {
176 	&mod_driverops,				/* drv_modops */
177 	(char *)sppp_module_description,	/* drv_linkinfo */
178 	&sppp_ops				/* drv_dev_ops */
179 };
180 
181 static struct modlinkage modlinkage = {
182 	MODREV_1,			/* ml_rev, has to be MODREV_1 */
183 	&modldrv,			/* ml_linkage, NULL-terminated list */
184 	NULL				/*  of linkage structures */
185 };
186 
187 int
188 _init(void)
189 {
190 	return (mod_install(&modlinkage));
191 }
192 
193 int
194 _fini(void)
195 {
196 	return (mod_remove(&modlinkage));
197 }
198 
199 int
200 _info(struct modinfo *modinfop)
201 {
202 	return (mod_info(&modlinkage, modinfop));
203 }
204 
205 /*
206  * _mi_driver_attach()
207  *
208  * Description:
209  *    Attach a point-to-point interface to the system.
210  */
211 static int
212 _mi_driver_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
213 {
214 	if (cmd != DDI_ATTACH) {
215 		return (DDI_FAILURE);
216 	}
217 	if (ddi_create_minor_node(dip, PPP_DRV_NAME, S_IFCHR,
218 	    0, DDI_PSEUDO, CLONE_DEV) == DDI_FAILURE) {
219 		ddi_remove_minor_node(dip, NULL);
220 		return (DDI_FAILURE);
221 	}
222 	sppp_dlpi_pinfoinit();
223 	return (DDI_SUCCESS);
224 }
225 
226 /*
227  * _mi_driver_detach()
228  *
229  * Description:
230  *    Detach an interface to the system.
231  */
232 static int
233 _mi_driver_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
234 {
235 	if (cmd != DDI_DETACH) {
236 		return (DDI_FAILURE);
237 	}
238 	ddi_remove_minor_node(dip, NULL);
239 	return (DDI_SUCCESS);
240 }
241 
242 /*
243  * _mi_driver_info()
244  *
245  * Description:
246  *    Translate "dev_t" to a pointer to the associated "dev_info_t".
247  */
248 /* ARGSUSED */
249 static int
250 _mi_driver_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
251 	void **result)
252 {
253 	int	rc;
254 
255 	switch (infocmd) {
256 	case DDI_INFO_DEVT2DEVINFO:
257 		if (_mi_dip == NULL) {
258 			rc = DDI_FAILURE;
259 		} else {
260 			*result = (void *)_mi_dip;
261 			rc = DDI_SUCCESS;
262 		}
263 		break;
264 	case DDI_INFO_DEVT2INSTANCE:
265 		*result = NULL;
266 		rc = DDI_SUCCESS;
267 		break;
268 	default:
269 		rc = DDI_FAILURE;
270 		break;
271 	}
272 	return (rc);
273 }
274