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 https://opensource.org/licenses/CDDL-1.0. 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 /* 23 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 * 26 * Copyright (c) 2016, Intel Corporation. 27 */ 28 29 #include <sys/types.h> 30 #include <sys/param.h> 31 #include <sys/stat.h> 32 #include <libudev.h> 33 #include <errno.h> 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <string.h> 37 #include <fcntl.h> 38 39 /* 40 * Linux persistent device strings for vdev labels 41 * 42 * based on udev_device_get_devid() at zfs/lib/libzfs/libzfs_import.c 43 */ 44 45 #define DEV_BYID_PATH "/dev/disk/by-id/" 46 47 static int 48 udev_device_get_devid(struct udev_device *dev, char *bufptr, size_t buflen) 49 { 50 struct udev_list_entry *entry; 51 const char *bus; 52 char devbyid[MAXPATHLEN]; 53 54 /* The bus based by-id path is preferred */ 55 bus = udev_device_get_property_value(dev, "ID_BUS"); 56 57 if (bus == NULL) { 58 const char *dm_uuid; 59 60 /* 61 * For multipath nodes use the persistent uuid based identifier 62 * 63 * Example: 'dm-uuid-mpath-35000c5006304de3f' 64 */ 65 dm_uuid = udev_device_get_property_value(dev, "DM_UUID"); 66 if (dm_uuid != NULL) { 67 (void) snprintf(bufptr, buflen, "dm-uuid-%s", dm_uuid); 68 return (0); 69 } 70 return (ENODATA); 71 } 72 73 /* 74 * locate the bus specific by-id link 75 * 76 * Example: 'scsi-MG03SCA300_350000494a8cb3d67-part1' 77 */ 78 (void) snprintf(devbyid, sizeof (devbyid), "%s%s-", DEV_BYID_PATH, bus); 79 entry = udev_device_get_devlinks_list_entry(dev); 80 while (entry != NULL) { 81 const char *name; 82 83 name = udev_list_entry_get_name(entry); 84 if (strncmp(name, devbyid, strlen(devbyid)) == 0) { 85 name += strlen(DEV_BYID_PATH); 86 (void) stpncpy(bufptr, name, buflen - 1); 87 bufptr[buflen - 1] = '\0'; 88 return (0); 89 } 90 entry = udev_list_entry_get_next(entry); 91 } 92 93 return (ENODATA); 94 } 95 96 /* 97 * Usage: devname2devid <devicepath> 98 * 99 * Examples: 100 * # ./devname2devid /dev/sda1 101 * devid scsi-350000394a8caede4-part1 102 * 103 * # ./devname2devid /dev/dm-1 104 * devid: 'dm-uuid-mpath-35000c5006304de3f' 105 * 106 * This program accepts a disk or disk slice path and prints a 107 * device id. 108 * 109 * Exit values: 110 * 0 - means success 111 * 1 - means failure 112 * 113 */ 114 int 115 main(int argc, char *argv[]) 116 { 117 struct udev *udev; 118 struct udev_device *dev = NULL; 119 char devid[128], nodepath[MAXPATHLEN]; 120 char *device, *sysname; 121 int ret; 122 123 if (argc == 1) { 124 (void) printf("%s <devicepath> [search path]\n", argv[0]); 125 exit(1); 126 } 127 device = argv[1]; 128 129 if ((udev = udev_new()) == NULL) { 130 perror("udev_new"); 131 exit(1); 132 } 133 134 /* resolve path to a runtime device node instance */ 135 if (realpath(device, nodepath) == NULL) { 136 perror("realpath"); 137 exit(1); 138 } 139 sysname = strrchr(nodepath, '/') + 1; 140 141 if ((dev = udev_device_new_from_subsystem_sysname(udev, "block", 142 sysname)) == NULL) { 143 perror(sysname); 144 exit(1); 145 } 146 147 if ((ret = udev_device_get_devid(dev, devid, sizeof (devid))) != 0) { 148 udev_device_unref(dev); 149 errno = ret; 150 perror(sysname); 151 exit(1); 152 } 153 154 (void) printf("devid %s\n", devid); 155 156 udev_device_unref(dev); 157 udev_unref(udev); 158 159 return (0); 160 } 161