xref: /illumos-gate/usr/src/uts/common/io/ppp/sppp/sppp_mod.c (revision 89a7715a55deca73d03076f5c24463717f0aaa91)
1 /*
2  * sppp_mod.c - modload support for PPP pseudo-device driver.
3  *
4  * Copyright 2007 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/systm.h>
53 #include <sys/ddi.h>
54 #include <sys/conf.h>
55 #include <sys/sunddi.h>
56 #include <sys/stat.h>
57 #include <sys/kstat.h>
58 #include <net/pppio.h>
59 #include <sys/modctl.h>
60 
61 #include "s_common.h"
62 #include "sppp.h"
63 
64 static int	_mi_driver_attach(dev_info_t *, ddi_attach_cmd_t);
65 static int	_mi_driver_detach(dev_info_t *, ddi_detach_cmd_t);
66 static int	_mi_driver_info(dev_info_t *, ddi_info_cmd_t, void *, void **);
67 
68 /*
69  * Globals for PPP multiplexer module wrapper
70  */
71 extern const char sppp_module_description[];
72 static dev_info_t *_mi_dip;
73 
74 #define	PPP_MI_HIWAT	(PPP_MTU * 16)	/* XXX find more meaningful value */
75 #define	PPP_MI_LOWAT	(PPP_MTU * 14)	/* XXX find more meaningful value */
76 
77 static struct module_info sppp_modinfo = {
78 	PPP_MOD_ID,		/* mi_idnum */
79 	PPP_DRV_NAME,		/* mi_idname */
80 	0,			/* mi_minpsz */
81 	PPP_MAXMTU,		/* mi_maxpsz */
82 	PPP_MI_HIWAT,		/* mi_hiwat */
83 	PPP_MI_LOWAT		/* mi_lowat */
84 };
85 
86 static struct qinit sppp_urinit = {
87 	NULL,			/* qi_putp */
88 	NULL,			/* qi_srvp */
89 	sppp_open,		/* qi_qopen */
90 	sppp_close,		/* qi_qclose */
91 	NULL,			/* qi_qadmin */
92 	&sppp_modinfo,		/* qi_minfo */
93 	NULL			/* qi_mstat */
94 };
95 
96 static struct qinit sppp_uwinit = {
97 	(int (*)())sppp_uwput,	/* qi_putp */
98 	(int (*)())sppp_uwsrv,	/* qi_srvp */
99 	NULL,			/* qi_qopen */
100 	NULL,			/* qi_qclose */
101 	NULL,			/* qi_qadmin */
102 	&sppp_modinfo,		/* qi_minfo */
103 	NULL			/* qi_mstat */
104 };
105 
106 static struct qinit sppp_lrinit = {
107 	(int (*)())sppp_lrput,	/* qi_putp */
108 	NULL,			/* qi_srvp */
109 	NULL,			/* qi_qopen */
110 	NULL,			/* qi_qclose */
111 	NULL,			/* qi_qadmin */
112 	&sppp_modinfo,		/* qi_minfo */
113 	NULL			/* qi_mstat */
114 };
115 
116 static struct qinit sppp_lwinit = {
117 	NULL,			/* qi_putp */
118 	(int (*)())sppp_lwsrv,	/* qi_srvp */
119 	NULL,			/* qi_qopen */
120 	NULL,			/* qi_qclose */
121 	NULL,			/* qi_qadmin */
122 	&sppp_modinfo,		/* qi_minfo */
123 	NULL			/* qi_mstat */
124 };
125 
126 static struct streamtab sppp_tab = {
127 	&sppp_urinit,		/* st_rdinit */
128 	&sppp_uwinit,		/* st_wrinit */
129 	&sppp_lrinit,		/* st_muxrinit */
130 	&sppp_lwinit		/* st_muxwrinit */
131 };
132 
133 /*
134  * Descriptions for flags values in cb_flags field:
135  *
136  * D_MTQPAIR:
137  *    An inner perimeter that spans the queue pair.
138  * D_MTOUTPERIM:
139  *    An outer perimeter that spans over all queues in the module.
140  * D_MTOCEXCL:
141  *    Open & close procedures are entered exclusively at outer perimeter.
142  * D_MTPUTSHARED:
143  *    Entry to put procedures are done with SHARED (reader) acess
144  *    and not EXCLUSIVE (writer) access.
145  *
146  * Therefore:
147  *
148  * 1. Open and close procedures are entered with EXCLUSIVE (writer)
149  *    access at the inner perimeter, and with EXCLUSIVE (writer) access at
150  *    the outer perimeter.
151  *
152  * 2. Put procedures are entered with SHARED (reader) access at the inner
153  *    perimeter, and with SHARED (reader) access at the outer perimeter.
154  *
155  * 3. Service procedures are entered with EXCLUSIVE (writer) access at
156  *    the inner perimeter, and with SHARED (reader) access at the
157  *    outer perimeter.
158  *
159  * Do not attempt to modify these flags unless the entire corresponding
160  * driver code is changed to accomodate the newly represented MT-STREAMS
161  * flags. Doing so without making proper modifications to the driver code
162  * will severely impact the intended driver behavior, and thus may affect
163  * the system's stability and performance.
164  */
165 DDI_DEFINE_STREAM_OPS(sppp_ops,						\
166 	nulldev, nulldev,						\
167 	_mi_driver_attach, _mi_driver_detach, nodev, _mi_driver_info,	\
168 	D_NEW | D_MP | D_MTQPAIR | D_MTOUTPERIM | D_MTOCEXCL | D_MTPUTSHARED, \
169 	&sppp_tab);
170 
171 static struct modldrv modldrv = {
172 	&mod_driverops,				/* drv_modops */
173 	(char *)sppp_module_description,	/* drv_linkinfo */
174 	&sppp_ops				/* drv_dev_ops */
175 };
176 
177 static struct modlinkage modlinkage = {
178 	MODREV_1,			/* ml_rev, has to be MODREV_1 */
179 	&modldrv,			/* ml_linkage, NULL-terminated list */
180 	NULL				/*  of linkage structures */
181 };
182 
183 int
184 _init(void)
185 {
186 	return (mod_install(&modlinkage));
187 }
188 
189 int
190 _fini(void)
191 {
192 	return (mod_remove(&modlinkage));
193 }
194 
195 int
196 _info(struct modinfo *modinfop)
197 {
198 	return (mod_info(&modlinkage, modinfop));
199 }
200 
201 /*
202  * _mi_driver_attach()
203  *
204  * Description:
205  *    Attach a point-to-point interface to the system.
206  */
207 static int
208 _mi_driver_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
209 {
210 	if (cmd != DDI_ATTACH) {
211 		return (DDI_FAILURE);
212 	}
213 	if (ddi_create_minor_node(dip, PPP_DRV_NAME, S_IFCHR,
214 	    0, DDI_PSEUDO, CLONE_DEV) == DDI_FAILURE) {
215 		ddi_remove_minor_node(dip, NULL);
216 		return (DDI_FAILURE);
217 	}
218 	sppp_dlpi_pinfoinit();
219 	return (DDI_SUCCESS);
220 }
221 
222 /*
223  * _mi_driver_detach()
224  *
225  * Description:
226  *    Detach an interface to the system.
227  */
228 static int
229 _mi_driver_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
230 {
231 	if (cmd != DDI_DETACH) {
232 		return (DDI_FAILURE);
233 	}
234 	ddi_remove_minor_node(dip, NULL);
235 	return (DDI_SUCCESS);
236 }
237 
238 /*
239  * _mi_driver_info()
240  *
241  * Description:
242  *    Translate "dev_t" to a pointer to the associated "dev_info_t".
243  */
244 /* ARGSUSED */
245 static int
246 _mi_driver_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
247 	void **result)
248 {
249 	int	rc;
250 
251 	switch (infocmd) {
252 	case DDI_INFO_DEVT2DEVINFO:
253 		if (_mi_dip == NULL) {
254 			rc = DDI_FAILURE;
255 		} else {
256 			*result = (void *)_mi_dip;
257 			rc = DDI_SUCCESS;
258 		}
259 		break;
260 	case DDI_INFO_DEVT2INSTANCE:
261 		*result = NULL;
262 		rc = DDI_SUCCESS;
263 		break;
264 	default:
265 		rc = DDI_FAILURE;
266 		break;
267 	}
268 	return (rc);
269 }
270