xref: /titanic_41/usr/src/uts/common/kmdb/kdrv.c (revision da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 /*
29  * The driver portion of kmdb, which manages /dev/kmdb and passes requests along
30  * to the kmdb misc module (kmdbmod).
31  */
32 
33 #include <sys/conf.h>
34 #include <sys/stat.h>
35 #include <sys/modctl.h>
36 #include <sys/ddi.h>
37 #include <sys/sunddi.h>
38 #include <sys/open.h>
39 #include <sys/kobj.h>
40 #include <sys/kdi.h>
41 #include <sys/policy.h>
42 #include <sys/kobj_impl.h>
43 #include <sys/kmdb.h>
44 #include <sys/sysmacros.h>
45 #include <sys/consdev.h>
46 
47 #define	KDRV_CFG_MAXLEN		2048
48 
49 static dev_info_t 		*kdrv_dip;
50 
51 /*ARGSUSED*/
52 static int
53 kdrv_open(dev_t *dev, int openflags, int otyp, cred_t *credp)
54 {
55 	if (otyp != OTYP_CHR)
56 		return (EINVAL);
57 
58 	if (secpolicy_kmdb(credp) != 0)
59 		return (EPERM);
60 
61 	return (0);
62 }
63 
64 /*ARGSUSED*/
65 static int
66 kdrv_close(dev_t dev, int openflags, int otyp, cred_t *credp)
67 {
68 	return (0);
69 }
70 
71 typedef struct kdrv_flags_map {
72 	const char *fm_name;
73 	int fm_defval;
74 	uint_t fm_flag;
75 } kdrv_flags_map_t;
76 
77 static const kdrv_flags_map_t kdrv_flags_map[] = {
78 	{ "kmdb-auto-entry", 1, KMDB_F_AUTO_ENTRY },
79 	{ "kmdb-trap-noswitch", 0, KMDB_F_TRAP_NOSWITCH },
80 	{ "kmdb-driver-debug", 0, KMDB_F_DRV_DEBUG },
81 	{ NULL }
82 };
83 
84 static int
85 kdrv_activate(intptr_t arg)
86 {
87 	uint_t flags;
88 	size_t memsz;
89 	char *cfg;
90 	size_t got;
91 	int i, rc;
92 
93 #if defined(__x86)
94 	if (cons_polledio == NULL) {
95 		cmn_err(CE_NOTE, "kmdb not supported: no console polled I/O");
96 		return (ENOTSUP);
97 	}
98 #endif
99 
100 	memsz = ddi_prop_get_int(DDI_DEV_T_ANY, kdrv_dip,
101 	    DDI_PROP_DONTPASS, "kmdb-memseg-size", 0);
102 
103 	for (flags = 0, i = 0; kdrv_flags_map[i].fm_name != NULL; i++) {
104 		const kdrv_flags_map_t *fm = &kdrv_flags_map[i];
105 		if (ddi_prop_get_int(DDI_DEV_T_ANY, kdrv_dip, DDI_PROP_DONTPASS,
106 		    (char *)fm->fm_name, fm->fm_defval))
107 			flags |= fm->fm_flag;
108 	}
109 
110 	cfg = kmem_alloc(KDRV_CFG_MAXLEN, KM_SLEEP);
111 
112 	if ((rc = copyinstr((caddr_t)arg, cfg, KDRV_CFG_MAXLEN, &got)) != 0) {
113 		kmem_free(cfg, KDRV_CFG_MAXLEN);
114 		return (rc == ENAMETOOLONG ? E2BIG : EFAULT);
115 	}
116 
117 	rc = kctl_modload_activate(memsz, cfg, flags);
118 
119 	kmem_free(cfg, KDRV_CFG_MAXLEN);
120 
121 	return (rc);
122 }
123 
124 static int
125 kdrv_deactivate(void)
126 {
127 	return (kctl_deactivate());
128 }
129 
130 /*ARGSUSED*/
131 static int
132 kdrv_ioctl(dev_t dev, int cmd, intptr_t arg, int flags, cred_t *credp,
133     int *rvalp)
134 {
135 	switch (cmd) {
136 	case KMDB_IOC_START:
137 		return (kdrv_activate(arg));
138 
139 	case KMDB_IOC_STOP:
140 		return (kdrv_deactivate());
141 
142 	default:
143 		return (EINVAL);
144 	}
145 }
146 
147 /*ARGSUSED*/
148 static int
149 kdrv_getinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
150 {
151 	int error = DDI_SUCCESS;
152 
153 	switch (infocmd) {
154 	case DDI_INFO_DEVT2DEVINFO:
155 		*result = kdrv_dip;
156 		break;
157 	case DDI_INFO_DEVT2INSTANCE:
158 		*result = (void *)(uintptr_t)getminor((dev_t)arg);
159 		break;
160 	default:
161 		*result = NULL;
162 		error = DDI_FAILURE;
163 	}
164 
165 	return (error);
166 }
167 
168 static int
169 kdrv_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
170 {
171 	if (cmd != DDI_ATTACH)
172 		return (DDI_FAILURE);
173 
174 	if (ddi_create_minor_node(dip, ddi_get_name(dip), S_IFCHR,
175 	    ddi_get_instance(dip), DDI_PSEUDO, 0) != DDI_SUCCESS)
176 		return (DDI_FAILURE);
177 
178 	kdrv_dip = dip;
179 
180 	if (kctl_attach(dip) != 0)
181 		return (DDI_FAILURE);
182 
183 	return (DDI_SUCCESS);
184 }
185 
186 static int
187 kdrv_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
188 {
189 	if (cmd != DDI_DETACH)
190 		return (DDI_FAILURE);
191 
192 	if (kctl_detach() == EBUSY)
193 		return (DDI_FAILURE);
194 
195 	ddi_remove_minor_node(dip, NULL);
196 
197 	return (DDI_SUCCESS);
198 }
199 
200 static struct cb_ops kdrv_cb_ops = {
201 	kdrv_open,
202 	kdrv_close,
203 	nodev,			/* not a block driver	*/
204 	nodev,			/* no print routine	*/
205 	nodev,			/* no dump routine	*/
206 	nodev,			/* no read routine	*/
207 	nodev,			/* no write routine	*/
208 	kdrv_ioctl,
209 	nodev,			/* no devmap routine	*/
210 	nodev,			/* no mmap routine	*/
211 	nodev,			/* no segmap routine	*/
212 	nochpoll,		/* no chpoll routine	*/
213 	ddi_prop_op,
214 	0,			/* not a STREAMS driver	*/
215 	D_NEW | D_MP,		/* safe for multi-thread/multi-processor */
216 };
217 
218 static struct dev_ops kdrv_ops = {
219 	DEVO_REV,		/* devo_rev */
220 	0,			/* devo_refcnt */
221 	kdrv_getinfo,		/* devo_getinfo */
222 	nulldev,		/* devo_identify */
223 	nulldev,		/* devo_probe */
224 	kdrv_attach,		/* devo_attach */
225 	kdrv_detach,		/* devo_detach */
226 	nodev,			/* devo_reset */
227 	&kdrv_cb_ops,		/* devo_cb_ops */
228 	(struct bus_ops *)0,	/* devo_bus_ops */
229 	NULL,			/* devo_power */
230 };
231 
232 static struct modldrv modldrv = {
233 	&mod_driverops,
234 	"kmdb driver %I%",
235 	&kdrv_ops
236 };
237 
238 static struct modlinkage modlinkage = {
239 	MODREV_1,
240 	(void *)&modldrv,
241 	NULL
242 };
243 
244 int
245 _init(void)
246 {
247 	return (mod_install(&modlinkage));
248 }
249 
250 int
251 _info(struct modinfo *modinfop)
252 {
253 	return (mod_info(&modlinkage, modinfop));
254 }
255 
256 int
257 _fini(void)
258 {
259 	return (mod_remove(&modlinkage));
260 }
261