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 Version 1.0 (CDDL-1.0). 6 * You can obtain a copy of the license from the top-level file 7 * "OPENSOLARIS.LICENSE" or at <http://opensource.org/licenses/CDDL-1.0>. 8 * You may not use this file except in compliance with the license. 9 * 10 * CDDL HEADER END 11 */ 12 13 /* 14 * Copyright (c) 2016, 2017, Intel Corporation. 15 */ 16 17 #ifdef HAVE_LIBUDEV 18 19 #include <errno.h> 20 #include <fcntl.h> 21 #include <libnvpair.h> 22 #include <libudev.h> 23 #include <libzfs.h> 24 #include <libzutil.h> 25 #include <pthread.h> 26 #include <stdlib.h> 27 #include <string.h> 28 29 #include <sys/sysevent/eventdefs.h> 30 #include <sys/sysevent/dev.h> 31 32 #include "zed_log.h" 33 #include "zed_disk_event.h" 34 #include "agents/zfs_agents.h" 35 36 /* 37 * Portions of ZED need to see disk events for disks belonging to ZFS pools. 38 * A libudev monitor is established to monitor block device actions and pass 39 * them on to internal ZED logic modules. Initially, zfs_mod.c is the only 40 * consumer and is the Linux equivalent for the illumos syseventd ZFS SLM 41 * module responsible for handling disk events for ZFS. 42 */ 43 44 pthread_t g_mon_tid; 45 struct udev *g_udev; 46 struct udev_monitor *g_mon; 47 48 49 #define DEV_BYID_PATH "/dev/disk/by-id/" 50 51 /* 64MB is minimum usable disk for ZFS */ 52 #define MINIMUM_SECTORS 131072 53 54 55 /* 56 * Post disk event to SLM module 57 * 58 * occurs in the context of monitor thread 59 */ 60 static void 61 zed_udev_event(const char *class, const char *subclass, nvlist_t *nvl) 62 { 63 char *strval; 64 uint64_t numval; 65 66 zed_log_msg(LOG_INFO, "zed_disk_event:"); 67 zed_log_msg(LOG_INFO, "\tclass: %s", class); 68 zed_log_msg(LOG_INFO, "\tsubclass: %s", subclass); 69 if (nvlist_lookup_string(nvl, DEV_NAME, &strval) == 0) 70 zed_log_msg(LOG_INFO, "\t%s: %s", DEV_NAME, strval); 71 if (nvlist_lookup_string(nvl, DEV_PATH, &strval) == 0) 72 zed_log_msg(LOG_INFO, "\t%s: %s", DEV_PATH, strval); 73 if (nvlist_lookup_string(nvl, DEV_IDENTIFIER, &strval) == 0) 74 zed_log_msg(LOG_INFO, "\t%s: %s", DEV_IDENTIFIER, strval); 75 if (nvlist_lookup_boolean(nvl, DEV_IS_PART) == B_TRUE) 76 zed_log_msg(LOG_INFO, "\t%s: B_TRUE", DEV_IS_PART); 77 if (nvlist_lookup_string(nvl, DEV_PHYS_PATH, &strval) == 0) 78 zed_log_msg(LOG_INFO, "\t%s: %s", DEV_PHYS_PATH, strval); 79 if (nvlist_lookup_uint64(nvl, DEV_SIZE, &numval) == 0) 80 zed_log_msg(LOG_INFO, "\t%s: %llu", DEV_SIZE, numval); 81 if (nvlist_lookup_uint64(nvl, ZFS_EV_POOL_GUID, &numval) == 0) 82 zed_log_msg(LOG_INFO, "\t%s: %llu", ZFS_EV_POOL_GUID, numval); 83 if (nvlist_lookup_uint64(nvl, ZFS_EV_VDEV_GUID, &numval) == 0) 84 zed_log_msg(LOG_INFO, "\t%s: %llu", ZFS_EV_VDEV_GUID, numval); 85 86 (void) zfs_agent_post_event(class, subclass, nvl); 87 } 88 89 /* 90 * dev_event_nvlist: place event schema into an nv pair list 91 * 92 * NAME VALUE (example) 93 * -------------- -------------------------------------------------------- 94 * DEV_NAME /dev/sdl 95 * DEV_PATH /devices/pci0000:00/0000:00:03.0/0000:04:00.0/host0/... 96 * DEV_IDENTIFIER ata-Hitachi_HTS725050A9A362_100601PCG420VLJ37DMC 97 * DEV_PHYS_PATH pci-0000:04:00.0-sas-0x4433221101000000-lun-0 98 * DEV_IS_PART --- 99 * DEV_SIZE 500107862016 100 * ZFS_EV_POOL_GUID 17523635698032189180 101 * ZFS_EV_VDEV_GUID 14663607734290803088 102 */ 103 static nvlist_t * 104 dev_event_nvlist(struct udev_device *dev) 105 { 106 nvlist_t *nvl; 107 char strval[128]; 108 const char *value, *path; 109 uint64_t guid; 110 111 if (nvlist_alloc(&nvl, NV_UNIQUE_NAME, 0) != 0) 112 return (NULL); 113 114 if (zfs_device_get_devid(dev, strval, sizeof (strval)) == 0) 115 (void) nvlist_add_string(nvl, DEV_IDENTIFIER, strval); 116 if (zfs_device_get_physical(dev, strval, sizeof (strval)) == 0) 117 (void) nvlist_add_string(nvl, DEV_PHYS_PATH, strval); 118 if ((path = udev_device_get_devnode(dev)) != NULL) 119 (void) nvlist_add_string(nvl, DEV_NAME, path); 120 if ((value = udev_device_get_devpath(dev)) != NULL) 121 (void) nvlist_add_string(nvl, DEV_PATH, value); 122 value = udev_device_get_devtype(dev); 123 if ((value != NULL && strcmp("partition", value) == 0) || 124 (udev_device_get_property_value(dev, "ID_PART_ENTRY_NUMBER") 125 != NULL)) { 126 (void) nvlist_add_boolean(nvl, DEV_IS_PART); 127 } 128 if ((value = udev_device_get_sysattr_value(dev, "size")) != NULL) { 129 uint64_t numval = DEV_BSIZE; 130 131 numval *= strtoull(value, NULL, 10); 132 (void) nvlist_add_uint64(nvl, DEV_SIZE, numval); 133 } 134 135 /* 136 * Grab the pool and vdev guids from blkid cache 137 */ 138 value = udev_device_get_property_value(dev, "ID_FS_UUID"); 139 if (value != NULL && (guid = strtoull(value, NULL, 10)) != 0) 140 (void) nvlist_add_uint64(nvl, ZFS_EV_POOL_GUID, guid); 141 142 value = udev_device_get_property_value(dev, "ID_FS_UUID_SUB"); 143 if (value != NULL && (guid = strtoull(value, NULL, 10)) != 0) 144 (void) nvlist_add_uint64(nvl, ZFS_EV_VDEV_GUID, guid); 145 146 /* 147 * Either a vdev guid or a devid must be present for matching 148 */ 149 if (!nvlist_exists(nvl, DEV_IDENTIFIER) && 150 !nvlist_exists(nvl, ZFS_EV_VDEV_GUID)) { 151 nvlist_free(nvl); 152 return (NULL); 153 } 154 155 return (nvl); 156 } 157 158 /* 159 * Listen for block device uevents 160 */ 161 static void * 162 zed_udev_monitor(void *arg) 163 { 164 struct udev_monitor *mon = arg; 165 char *tmp, *tmp2; 166 167 zed_log_msg(LOG_INFO, "Waiting for new udev disk events..."); 168 169 while (1) { 170 struct udev_device *dev; 171 const char *action, *type, *part, *sectors; 172 const char *bus, *uuid; 173 const char *class, *subclass; 174 nvlist_t *nvl; 175 boolean_t is_zfs = B_FALSE; 176 177 /* allow a cancellation while blocked (recvmsg) */ 178 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL); 179 180 /* blocks at recvmsg until an event occurs */ 181 if ((dev = udev_monitor_receive_device(mon)) == NULL) { 182 zed_log_msg(LOG_WARNING, "zed_udev_monitor: receive " 183 "device error %d", errno); 184 continue; 185 } 186 187 /* allow all steps to complete before a cancellation */ 188 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL); 189 190 /* 191 * Strongly typed device is the preferred filter 192 */ 193 type = udev_device_get_property_value(dev, "ID_FS_TYPE"); 194 if (type != NULL && type[0] != '\0') { 195 if (strcmp(type, "zfs_member") == 0) { 196 is_zfs = B_TRUE; 197 } else { 198 /* not ours, so skip */ 199 zed_log_msg(LOG_INFO, "zed_udev_monitor: skip " 200 "%s (in use by %s)", 201 udev_device_get_devnode(dev), type); 202 udev_device_unref(dev); 203 continue; 204 } 205 } 206 207 /* 208 * if this is a disk and it is partitioned, then the 209 * zfs label will reside in a DEVTYPE=partition and 210 * we can skip passing this event 211 */ 212 type = udev_device_get_property_value(dev, "DEVTYPE"); 213 part = udev_device_get_property_value(dev, 214 "ID_PART_TABLE_TYPE"); 215 if (type != NULL && type[0] != '\0' && 216 strcmp(type, "disk") == 0 && 217 part != NULL && part[0] != '\0') { 218 zed_log_msg(LOG_INFO, 219 "%s: skip %s since it has a %s partition already", 220 __func__, 221 udev_device_get_property_value(dev, "DEVNAME"), 222 part); 223 /* skip and wait for partition event */ 224 udev_device_unref(dev); 225 continue; 226 } 227 228 /* 229 * ignore small partitions 230 */ 231 sectors = udev_device_get_property_value(dev, 232 "ID_PART_ENTRY_SIZE"); 233 if (sectors == NULL) 234 sectors = udev_device_get_sysattr_value(dev, "size"); 235 if (sectors != NULL && 236 strtoull(sectors, NULL, 10) < MINIMUM_SECTORS) { 237 zed_log_msg(LOG_INFO, 238 "%s: %s sectors %s < %llu (minimum)", 239 __func__, 240 udev_device_get_property_value(dev, "DEVNAME"), 241 sectors, MINIMUM_SECTORS); 242 udev_device_unref(dev); 243 continue; 244 } 245 246 /* 247 * If the blkid probe didn't find ZFS, then a persistent 248 * device id string is required in the message schema 249 * for matching with vdevs. Preflight here for expected 250 * udev information. 251 */ 252 bus = udev_device_get_property_value(dev, "ID_BUS"); 253 uuid = udev_device_get_property_value(dev, "DM_UUID"); 254 if (!is_zfs && (bus == NULL && uuid == NULL)) { 255 zed_log_msg(LOG_INFO, "zed_udev_monitor: %s no devid " 256 "source", udev_device_get_devnode(dev)); 257 udev_device_unref(dev); 258 continue; 259 } 260 261 action = udev_device_get_action(dev); 262 if (strcmp(action, "add") == 0) { 263 class = EC_DEV_ADD; 264 subclass = ESC_DISK; 265 } else if (strcmp(action, "remove") == 0) { 266 class = EC_DEV_REMOVE; 267 subclass = ESC_DISK; 268 } else if (strcmp(action, "change") == 0) { 269 class = EC_DEV_STATUS; 270 subclass = ESC_DEV_DLE; 271 } else { 272 zed_log_msg(LOG_WARNING, "zed_udev_monitor: %s unknown", 273 action); 274 udev_device_unref(dev); 275 continue; 276 } 277 278 /* 279 * Special case an EC_DEV_ADD for multipath devices 280 * 281 * When a multipath device is created, udev reports the 282 * following: 283 * 284 * 1. "add" event of the dm device for the multipath device 285 * (like /dev/dm-3). 286 * 2. "change" event to create the actual multipath device 287 * symlink (like /dev/mapper/mpatha). The event also 288 * passes back the relevant DM vars we care about, like 289 * DM_UUID. 290 * 3. Another "change" event identical to #2 (that we ignore). 291 * 292 * To get the behavior we want, we treat the "change" event 293 * in #2 as a "add" event; as if "/dev/mapper/mpatha" was 294 * a new disk being added. 295 */ 296 if (strcmp(class, EC_DEV_STATUS) == 0 && 297 udev_device_get_property_value(dev, "DM_UUID") && 298 udev_device_get_property_value(dev, "MPATH_SBIN_PATH")) { 299 tmp = (char *)udev_device_get_devnode(dev); 300 tmp2 = zfs_get_underlying_path(tmp); 301 if (tmp && tmp2 && (strcmp(tmp, tmp2) != 0)) { 302 /* 303 * We have a real underlying device, which 304 * means that this multipath "change" event is 305 * an "add" event. 306 * 307 * If the multipath device and the underlying 308 * dev are the same name (i.e. /dev/dm-5), then 309 * there is no real underlying disk for this 310 * multipath device, and so this "change" event 311 * really is a multipath removal. 312 */ 313 class = EC_DEV_ADD; 314 subclass = ESC_DISK; 315 } else { 316 tmp = (char *) 317 udev_device_get_property_value(dev, 318 "DM_NR_VALID_PATHS"); 319 /* treat as a multipath remove */ 320 if (tmp != NULL && strcmp(tmp, "0") == 0) { 321 class = EC_DEV_REMOVE; 322 subclass = ESC_DISK; 323 } 324 } 325 free(tmp2); 326 } 327 328 /* 329 * Special case an EC_DEV_ADD for scsi_debug devices 330 * 331 * These devices require a udevadm trigger command after 332 * creation in order to register the vdev_id scsidebug alias 333 * rule (adds a persistent path (phys_path) used for fault 334 * management automated tests in the ZFS test suite. 335 * 336 * After udevadm trigger command, event registers as a "change" 337 * event but needs to instead be handled as another "add" event 338 * to allow for disk labeling and partitioning to occur. 339 */ 340 if (strcmp(class, EC_DEV_STATUS) == 0 && 341 udev_device_get_property_value(dev, "ID_VDEV") && 342 udev_device_get_property_value(dev, "ID_MODEL")) { 343 const char *id_model, *id_model_sd = "scsi_debug"; 344 345 id_model = udev_device_get_property_value(dev, 346 "ID_MODEL"); 347 if (strcmp(id_model, id_model_sd) == 0) { 348 class = EC_DEV_ADD; 349 subclass = ESC_DISK; 350 } 351 } 352 353 if ((nvl = dev_event_nvlist(dev)) != NULL) { 354 zed_udev_event(class, subclass, nvl); 355 nvlist_free(nvl); 356 } 357 358 udev_device_unref(dev); 359 } 360 361 return (NULL); 362 } 363 364 int 365 zed_disk_event_init() 366 { 367 int fd, fflags; 368 369 if ((g_udev = udev_new()) == NULL) { 370 zed_log_msg(LOG_WARNING, "udev_new failed (%d)", errno); 371 return (-1); 372 } 373 374 /* Set up a udev monitor for block devices */ 375 g_mon = udev_monitor_new_from_netlink(g_udev, "udev"); 376 udev_monitor_filter_add_match_subsystem_devtype(g_mon, "block", "disk"); 377 udev_monitor_filter_add_match_subsystem_devtype(g_mon, "block", 378 "partition"); 379 udev_monitor_enable_receiving(g_mon); 380 381 /* Make sure monitoring socket is blocking */ 382 fd = udev_monitor_get_fd(g_mon); 383 if ((fflags = fcntl(fd, F_GETFL)) & O_NONBLOCK) 384 (void) fcntl(fd, F_SETFL, fflags & ~O_NONBLOCK); 385 386 /* spawn a thread to monitor events */ 387 if (pthread_create(&g_mon_tid, NULL, zed_udev_monitor, g_mon) != 0) { 388 udev_monitor_unref(g_mon); 389 udev_unref(g_udev); 390 zed_log_msg(LOG_WARNING, "pthread_create failed"); 391 return (-1); 392 } 393 394 pthread_setname_np(g_mon_tid, "udev monitor"); 395 zed_log_msg(LOG_INFO, "zed_disk_event_init"); 396 397 return (0); 398 } 399 400 void 401 zed_disk_event_fini() 402 { 403 /* cancel monitor thread at recvmsg() */ 404 (void) pthread_cancel(g_mon_tid); 405 (void) pthread_join(g_mon_tid, NULL); 406 407 /* cleanup udev resources */ 408 udev_monitor_unref(g_mon); 409 udev_unref(g_udev); 410 411 zed_log_msg(LOG_INFO, "zed_disk_event_fini"); 412 } 413 414 #else 415 416 #include "zed_disk_event.h" 417 418 int 419 zed_disk_event_init() 420 { 421 return (0); 422 } 423 424 void 425 zed_disk_event_fini() 426 { 427 } 428 429 #endif /* HAVE_LIBUDEV */ 430