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 #include "libdevinfo.h"
27 #include <strings.h>
28 #include <sys/modctl.h>
29
30 /*
31 *
32 * This file contains interfaces to translate <driver><instance><minorname>
33 * information into /devices and /dev paths. It does this using interfaces to
34 * the kernel instance tree so that it can provide translations for devices
35 * which are no longer present. An example consumer of these interfaces is
36 * iostat(8) - which shows, in its first iteration, activity since reboot.
37 * With persistant kstats, a device which was busy a long time ago can still
38 * have a decaying presence in iostat output, and that output, when '-n' is
39 * used, should show the public name.
40 */
41
42 typedef struct {
43 di_devlink_handle_t i_devlink_hdl;
44 } *idim_t;
45
46 di_dim_t
di_dim_init()47 di_dim_init()
48 {
49 idim_t idim;
50
51 if ((idim = (idim_t)malloc(sizeof (*idim))) == NULL)
52 return (NULL);
53 idim->i_devlink_hdl = di_devlink_init(NULL, 0);
54 if (idim->i_devlink_hdl == NULL) {
55 free(idim);
56 return (NULL);
57 }
58 return ((di_dim_t)idim);
59 }
60
61 void
di_dim_fini(di_dim_t dim)62 di_dim_fini(di_dim_t dim)
63 {
64 idim_t idim = (idim_t)dim;
65
66 if (idim->i_devlink_hdl) {
67 (void) di_devlink_fini(&idim->i_devlink_hdl);
68 }
69 free(idim);
70 }
71
72 /*ARGSUSED*/
73 char *
di_dim_path_devices(di_dim_t dim,char * drv_name,int instance,char * minor_name)74 di_dim_path_devices(di_dim_t dim, char *drv_name, int instance,
75 char *minor_name)
76 {
77 major_t major;
78 int len;
79 int mlen;
80 char *devices;
81
82 /* convert drv_name to major_t */
83 if (modctl(MODGETMAJBIND, drv_name, strlen(drv_name) + 1, &major) < 0)
84 return (NULL);
85
86 /* find the length of the devices path given major,instance */
87 if (modctl(MODGETDEVFSPATH_MI_LEN, major, instance, &len) != 0)
88 return (NULL);
89
90 /*
91 * MODGETDEVFSPATH_MI_LEN result includes '\0' termination, but we
92 * may need to add space for ":<minor_name>"
93 */
94 if (minor_name)
95 mlen = len + 1 + strlen(minor_name);
96 else
97 mlen = len;
98 if ((devices = (char *)malloc(mlen)) == NULL)
99 return (NULL);
100
101 if (modctl(MODGETDEVFSPATH_MI, major, instance, len, devices) != 0) {
102 free(devices);
103 return (NULL);
104 }
105
106 if (minor_name) {
107 /* add ':<minot_name>' to the end of /devices path */
108 (void) strcat(devices, ":");
109 (void) strcat(devices, minor_name);
110 }
111 return (devices);
112 }
113
114 /* di_dim_path_dev di_devlink callback */
115 static int
di_dim_path_dev_callback(di_devlink_t dl,void * arg)116 di_dim_path_dev_callback(di_devlink_t dl, void *arg)
117 {
118 char **devp = (char **)arg;
119 char *devpath = (char *)di_devlink_path(dl);
120
121 if (devpath)
122 *devp = strdup(devpath);
123 return (DI_WALK_TERMINATE);
124 }
125
126 char *
di_dim_path_dev(di_dim_t dim,char * drv_name,int instance,char * minor_name)127 di_dim_path_dev(di_dim_t dim, char *drv_name, int instance, char *minor_name)
128 {
129 idim_t idim = (idim_t)dim;
130 char *devices;
131 char *dev = NULL;
132
133 /* we must have a minor_name to resolve to a public name */
134 if (minor_name == NULL)
135 return (NULL);
136
137 /* convert <driver><instance><minor_name> to /devices path */
138 devices = di_dim_path_devices(dim, drv_name, instance, minor_name);
139 if (devices == NULL)
140 return (NULL);
141
142 /* convert /devices path to /dev path */
143 (void) di_devlink_walk(idim->i_devlink_hdl, NULL,
144 devices, DI_PRIMARY_LINK, (void *)&dev, di_dim_path_dev_callback);
145 free(devices);
146 return (dev);
147 }
148