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 2006 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 #include "libdevinfo.h"
29 #include <strings.h>
30 #include <sys/modctl.h>
31
32 /*
33 *
34 * This file contains interfaces to translate <driver><instance><minorname>
35 * information into /devices and /dev paths. It does this using interfaces to
36 * the kernel instance tree so that it can provide translations for devices
37 * which are no longer present. An example consumer of these interfaces is
38 * iostat(1M) - which shows, in its first iteration, activity since reboot.
39 * With persistant kstats, a device which was busy a long time ago can still
40 * have a decaying presence in iostat output, and that output, when '-n' is
41 * used, should show the public name.
42 */
43
44 typedef struct {
45 di_devlink_handle_t i_devlink_hdl;
46 } *idim_t;
47
48 di_dim_t
di_dim_init()49 di_dim_init()
50 {
51 idim_t idim;
52
53 if ((idim = (idim_t)malloc(sizeof (*idim))) == NULL)
54 return (NULL);
55 idim->i_devlink_hdl = di_devlink_init(NULL, 0);
56 if (idim->i_devlink_hdl == NULL) {
57 free(idim);
58 return (NULL);
59 }
60 return ((di_dim_t)idim);
61 }
62
63 void
di_dim_fini(di_dim_t dim)64 di_dim_fini(di_dim_t dim)
65 {
66 idim_t idim = (idim_t)dim;
67
68 if (idim->i_devlink_hdl) {
69 (void) di_devlink_fini(&idim->i_devlink_hdl);
70 }
71 free(idim);
72 }
73
74 /*ARGSUSED*/
75 char *
di_dim_path_devices(di_dim_t dim,char * drv_name,int instance,char * minor_name)76 di_dim_path_devices(di_dim_t dim, char *drv_name, int instance,
77 char *minor_name)
78 {
79 major_t major;
80 int len;
81 int mlen;
82 char *devices;
83
84 /* convert drv_name to major_t */
85 if (modctl(MODGETMAJBIND, drv_name, strlen(drv_name) + 1, &major) < 0)
86 return (NULL);
87
88 /* find the length of the devices path given major,instance */
89 if (modctl(MODGETDEVFSPATH_MI_LEN, major, instance, &len) != 0)
90 return (NULL);
91
92 /*
93 * MODGETDEVFSPATH_MI_LEN result includes '\0' termination, but we
94 * may need to add space for ":<minor_name>"
95 */
96 if (minor_name)
97 mlen = len + 1 + strlen(minor_name);
98 else
99 mlen = len;
100 if ((devices = (char *)malloc(mlen)) == NULL)
101 return (NULL);
102
103 if (modctl(MODGETDEVFSPATH_MI, major, instance, len, devices) != 0) {
104 free(devices);
105 return (NULL);
106 }
107
108 if (minor_name) {
109 /* add ':<minot_name>' to the end of /devices path */
110 (void) strcat(devices, ":");
111 (void) strcat(devices, minor_name);
112 }
113 return (devices);
114 }
115
116 /* di_dim_path_dev di_devlink callback */
117 static int
di_dim_path_dev_callback(di_devlink_t dl,void * arg)118 di_dim_path_dev_callback(di_devlink_t dl, void *arg)
119 {
120 char **devp = (char **)arg;
121 char *devpath = (char *)di_devlink_path(dl);
122
123 if (devpath)
124 *devp = strdup(devpath);
125 return (DI_WALK_TERMINATE);
126 }
127
128 char *
di_dim_path_dev(di_dim_t dim,char * drv_name,int instance,char * minor_name)129 di_dim_path_dev(di_dim_t dim, char *drv_name, int instance, char *minor_name)
130 {
131 idim_t idim = (idim_t)dim;
132 char *devices;
133 char *dev = NULL;
134
135 /* we must have a minor_name to resolve to a public name */
136 if (minor_name == NULL)
137 return (NULL);
138
139 /* convert <driver><instance><minor_name> to /devices path */
140 devices = di_dim_path_devices(dim, drv_name, instance, minor_name);
141 if (devices == NULL)
142 return (NULL);
143
144 /* convert /devices path to /dev path */
145 (void) di_devlink_walk(idim->i_devlink_hdl, NULL,
146 devices, DI_PRIMARY_LINK, (void *)&dev, di_dim_path_dev_callback);
147 free(devices);
148 return (dev);
149 }
150