xref: /freebsd/sys/contrib/openzfs/cmd/zed/zed_disk_event.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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		131072ULL
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 	const 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, DEV_PARENT_SIZE, &numval) == 0)
82 		zed_log_msg(LOG_INFO, "\t%s: %llu", DEV_PARENT_SIZE, numval);
83 	if (nvlist_lookup_uint64(nvl, ZFS_EV_POOL_GUID, &numval) == 0)
84 		zed_log_msg(LOG_INFO, "\t%s: %llu", ZFS_EV_POOL_GUID, numval);
85 	if (nvlist_lookup_uint64(nvl, ZFS_EV_VDEV_GUID, &numval) == 0)
86 		zed_log_msg(LOG_INFO, "\t%s: %llu", ZFS_EV_VDEV_GUID, numval);
87 
88 	(void) zfs_agent_post_event(class, subclass, nvl);
89 }
90 
91 /*
92  * dev_event_nvlist: place event schema into an nv pair list
93  *
94  * NAME			VALUE (example)
95  * --------------	--------------------------------------------------------
96  * DEV_NAME		/dev/sdl
97  * DEV_PATH		/devices/pci0000:00/0000:00:03.0/0000:04:00.0/host0/...
98  * DEV_IDENTIFIER	ata-Hitachi_HTS725050A9A362_100601PCG420VLJ37DMC
99  * DEV_PHYS_PATH	pci-0000:04:00.0-sas-0x4433221101000000-lun-0
100  * DEV_IS_PART		---
101  * DEV_SIZE		500107862016
102  * ZFS_EV_POOL_GUID	17523635698032189180
103  * ZFS_EV_VDEV_GUID	14663607734290803088
104  */
105 static nvlist_t *
106 dev_event_nvlist(struct udev_device *dev)
107 {
108 	nvlist_t *nvl;
109 	char strval[128];
110 	const char *value, *path;
111 	uint64_t guid;
112 
113 	if (nvlist_alloc(&nvl, NV_UNIQUE_NAME, 0) != 0)
114 		return (NULL);
115 
116 	if (zfs_device_get_devid(dev, strval, sizeof (strval)) == 0)
117 		(void) nvlist_add_string(nvl, DEV_IDENTIFIER, strval);
118 	if (zfs_device_get_physical(dev, strval, sizeof (strval)) == 0)
119 		(void) nvlist_add_string(nvl, DEV_PHYS_PATH, strval);
120 	if ((path = udev_device_get_devnode(dev)) != NULL)
121 		(void) nvlist_add_string(nvl, DEV_NAME, path);
122 	if ((value = udev_device_get_devpath(dev)) != NULL)
123 		(void) nvlist_add_string(nvl, DEV_PATH, value);
124 	value = udev_device_get_devtype(dev);
125 	if ((value != NULL && strcmp("partition", value) == 0) ||
126 	    (udev_device_get_property_value(dev, "ID_PART_ENTRY_NUMBER")
127 	    != NULL)) {
128 		(void) nvlist_add_boolean(nvl, DEV_IS_PART);
129 	}
130 	if ((value = udev_device_get_sysattr_value(dev, "size")) != NULL) {
131 		uint64_t numval = DEV_BSIZE;
132 
133 		numval *= strtoull(value, NULL, 10);
134 		(void) nvlist_add_uint64(nvl, DEV_SIZE, numval);
135 
136 		/*
137 		 * If the device has a parent, then get the parent block
138 		 * device's size as well.  For example, /dev/sda1's parent
139 		 * is /dev/sda.
140 		 */
141 		struct udev_device *parent_dev = udev_device_get_parent(dev);
142 		if ((value = udev_device_get_sysattr_value(parent_dev, "size"))
143 		    != NULL) {
144 			uint64_t numval = DEV_BSIZE;
145 
146 			numval *= strtoull(value, NULL, 10);
147 			(void) nvlist_add_uint64(nvl, DEV_PARENT_SIZE, numval);
148 		}
149 	}
150 
151 	/*
152 	 * Grab the pool and vdev guids from blkid cache
153 	 */
154 	value = udev_device_get_property_value(dev, "ID_FS_UUID");
155 	if (value != NULL && (guid = strtoull(value, NULL, 10)) != 0)
156 		(void) nvlist_add_uint64(nvl, ZFS_EV_POOL_GUID, guid);
157 
158 	value = udev_device_get_property_value(dev, "ID_FS_UUID_SUB");
159 	if (value != NULL && (guid = strtoull(value, NULL, 10)) != 0)
160 		(void) nvlist_add_uint64(nvl, ZFS_EV_VDEV_GUID, guid);
161 
162 	/*
163 	 * Either a vdev guid or a devid must be present for matching
164 	 */
165 	if (!nvlist_exists(nvl, DEV_IDENTIFIER) &&
166 	    !nvlist_exists(nvl, ZFS_EV_VDEV_GUID)) {
167 		nvlist_free(nvl);
168 		return (NULL);
169 	}
170 
171 	return (nvl);
172 }
173 
174 /*
175  *  Listen for block device uevents
176  */
177 static void *
178 zed_udev_monitor(void *arg)
179 {
180 	struct udev_monitor *mon = arg;
181 	const char *tmp;
182 	char *tmp2;
183 
184 	zed_log_msg(LOG_INFO, "Waiting for new udev disk events...");
185 
186 	while (1) {
187 		struct udev_device *dev;
188 		const char *action, *type, *part, *sectors;
189 		const char *bus, *uuid, *devpath;
190 		const char *class, *subclass;
191 		nvlist_t *nvl;
192 		boolean_t is_zfs = B_FALSE;
193 
194 		/* allow a cancellation while blocked (recvmsg) */
195 		pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
196 
197 		/* blocks at recvmsg until an event occurs */
198 		if ((dev = udev_monitor_receive_device(mon)) == NULL) {
199 			zed_log_msg(LOG_WARNING, "zed_udev_monitor: receive "
200 			    "device error %d", errno);
201 			continue;
202 		}
203 
204 		/* allow all steps to complete before a cancellation */
205 		pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
206 
207 		/*
208 		 * Strongly typed device is the preferred filter
209 		 */
210 		type = udev_device_get_property_value(dev, "ID_FS_TYPE");
211 		if (type != NULL && type[0] != '\0') {
212 			if (strcmp(type, "zfs_member") == 0) {
213 				is_zfs = B_TRUE;
214 			} else {
215 				/* not ours, so skip */
216 				zed_log_msg(LOG_INFO, "zed_udev_monitor: skip "
217 				    "%s (in use by %s)",
218 				    udev_device_get_devnode(dev), type);
219 				udev_device_unref(dev);
220 				continue;
221 			}
222 		}
223 
224 		/*
225 		 * if this is a disk and it is partitioned, then the
226 		 * zfs label will reside in a DEVTYPE=partition and
227 		 * we can skip passing this event
228 		 *
229 		 * Special case: Blank disks are sometimes reported with
230 		 * an erroneous 'atari' partition, and should not be
231 		 * excluded from being used as an autoreplace disk:
232 		 *
233 		 * https://github.com/openzfs/zfs/issues/13497
234 		 */
235 		type = udev_device_get_property_value(dev, "DEVTYPE");
236 		part = udev_device_get_property_value(dev,
237 		    "ID_PART_TABLE_TYPE");
238 		if (type != NULL && type[0] != '\0' &&
239 		    strcmp(type, "disk") == 0 &&
240 		    part != NULL && part[0] != '\0') {
241 			const char *devname =
242 			    udev_device_get_property_value(dev, "DEVNAME");
243 
244 			if (strcmp(part, "atari") == 0) {
245 				zed_log_msg(LOG_INFO,
246 				    "%s: %s is reporting an atari partition, "
247 				    "but we're going to assume it's a false "
248 				    "positive and still use it (issue #13497)",
249 				    __func__, devname);
250 			} else {
251 				zed_log_msg(LOG_INFO,
252 				    "%s: skip %s since it has a %s partition "
253 				    "already", __func__, devname, part);
254 				/* skip and wait for partition event */
255 				udev_device_unref(dev);
256 				continue;
257 			}
258 		}
259 
260 		/*
261 		 * ignore small partitions
262 		 */
263 		sectors = udev_device_get_property_value(dev,
264 		    "ID_PART_ENTRY_SIZE");
265 		if (sectors == NULL)
266 			sectors = udev_device_get_sysattr_value(dev, "size");
267 		if (sectors != NULL &&
268 		    strtoull(sectors, NULL, 10) < MINIMUM_SECTORS) {
269 			zed_log_msg(LOG_INFO,
270 			    "%s: %s sectors %s < %llu (minimum)",
271 			    __func__,
272 			    udev_device_get_property_value(dev, "DEVNAME"),
273 			    sectors, MINIMUM_SECTORS);
274 			udev_device_unref(dev);
275 			continue;
276 		}
277 
278 		/*
279 		 * If the blkid probe didn't find ZFS, then a persistent
280 		 * device id string is required in the message schema
281 		 * for matching with vdevs. Preflight here for expected
282 		 * udev information.
283 		 *
284 		 * Special case:
285 		 * NVMe devices don't have ID_BUS set (at least on RHEL 7-8),
286 		 * but they are valid for autoreplace.  Add a special case for
287 		 * them by searching for "/nvme/" in the udev DEVPATH:
288 		 *
289 		 * DEVPATH=/devices/pci0000:00/0000:00:1e.0/nvme/nvme2/nvme2n1
290 		 */
291 		bus = udev_device_get_property_value(dev, "ID_BUS");
292 		uuid = udev_device_get_property_value(dev, "DM_UUID");
293 		devpath = udev_device_get_devpath(dev);
294 		if (!is_zfs && (bus == NULL && uuid == NULL &&
295 		    strstr(devpath, "/nvme/") == NULL)) {
296 			zed_log_msg(LOG_INFO, "zed_udev_monitor: %s no devid "
297 			    "source", udev_device_get_devnode(dev));
298 			udev_device_unref(dev);
299 			continue;
300 		}
301 
302 		action = udev_device_get_action(dev);
303 		if (strcmp(action, "add") == 0) {
304 			class = EC_DEV_ADD;
305 			subclass = ESC_DISK;
306 		} else if (strcmp(action, "remove") == 0) {
307 			class = EC_DEV_REMOVE;
308 			subclass = ESC_DISK;
309 		} else if (strcmp(action, "change") == 0) {
310 			class = EC_DEV_STATUS;
311 			subclass = ESC_DEV_DLE;
312 		} else {
313 			zed_log_msg(LOG_WARNING, "zed_udev_monitor: %s unknown",
314 			    action);
315 			udev_device_unref(dev);
316 			continue;
317 		}
318 
319 		/*
320 		 * Special case an EC_DEV_ADD for multipath devices
321 		 *
322 		 * When a multipath device is created, udev reports the
323 		 * following:
324 		 *
325 		 * 1.	"add" event of the dm device for the multipath device
326 		 *	(like /dev/dm-3).
327 		 * 2.	"change" event to create the actual multipath device
328 		 *	symlink (like /dev/mapper/mpatha).  The event also
329 		 *	passes back the relevant DM vars we care about, like
330 		 *	DM_UUID.
331 		 * 3.	Another "change" event identical to #2 (that we ignore).
332 		 *
333 		 * To get the behavior we want, we treat the "change" event
334 		 * in #2 as a "add" event; as if "/dev/mapper/mpatha" was
335 		 * a new disk being added.
336 		 */
337 		if (strcmp(class, EC_DEV_STATUS) == 0 &&
338 		    udev_device_get_property_value(dev, "DM_UUID") &&
339 		    udev_device_get_property_value(dev, "MPATH_SBIN_PATH")) {
340 			tmp = udev_device_get_devnode(dev);
341 			tmp2 = zfs_get_underlying_path(tmp);
342 			if (tmp && tmp2 && (strcmp(tmp, tmp2) != 0)) {
343 				/*
344 				 * We have a real underlying device, which
345 				 * means that this multipath "change" event is
346 				 * an "add" event.
347 				 *
348 				 * If the multipath device and the underlying
349 				 * dev are the same name (i.e. /dev/dm-5), then
350 				 * there is no real underlying disk for this
351 				 * multipath device, and so this "change" event
352 				 * really is a multipath removal.
353 				 */
354 				class = EC_DEV_ADD;
355 				subclass = ESC_DISK;
356 			} else {
357 				tmp = udev_device_get_property_value(dev,
358 				    "DM_NR_VALID_PATHS");
359 				/* treat as a multipath remove */
360 				if (tmp != NULL && strcmp(tmp, "0") == 0) {
361 					class = EC_DEV_REMOVE;
362 					subclass = ESC_DISK;
363 				}
364 			}
365 			free(tmp2);
366 		}
367 
368 		/*
369 		 * Special case an EC_DEV_ADD for scsi_debug devices
370 		 *
371 		 * These devices require a udevadm trigger command after
372 		 * creation in order to register the vdev_id scsidebug alias
373 		 * rule (adds a persistent path (phys_path) used for fault
374 		 * management automated tests in the ZFS test suite.
375 		 *
376 		 * After udevadm trigger command, event registers as a "change"
377 		 * event but needs to instead be handled as another "add" event
378 		 * to allow for disk labeling and partitioning to occur.
379 		 */
380 		if (strcmp(class, EC_DEV_STATUS) == 0 &&
381 		    udev_device_get_property_value(dev, "ID_VDEV") &&
382 		    udev_device_get_property_value(dev, "ID_MODEL")) {
383 			const char *id_model, *id_model_sd = "scsi_debug";
384 
385 			id_model = udev_device_get_property_value(dev,
386 			    "ID_MODEL");
387 			if (strcmp(id_model, id_model_sd) == 0) {
388 				class = EC_DEV_ADD;
389 				subclass = ESC_DISK;
390 			}
391 		}
392 
393 		if ((nvl = dev_event_nvlist(dev)) != NULL) {
394 			zed_udev_event(class, subclass, nvl);
395 			nvlist_free(nvl);
396 		}
397 
398 		udev_device_unref(dev);
399 	}
400 
401 	return (NULL);
402 }
403 
404 int
405 zed_disk_event_init(void)
406 {
407 	int fd, fflags;
408 
409 	if ((g_udev = udev_new()) == NULL) {
410 		zed_log_msg(LOG_WARNING, "udev_new failed (%d)", errno);
411 		return (-1);
412 	}
413 
414 	/* Set up a udev monitor for block devices */
415 	g_mon = udev_monitor_new_from_netlink(g_udev, "udev");
416 	udev_monitor_filter_add_match_subsystem_devtype(g_mon, "block", "disk");
417 	udev_monitor_filter_add_match_subsystem_devtype(g_mon, "block",
418 	    "partition");
419 	udev_monitor_enable_receiving(g_mon);
420 
421 	/* Make sure monitoring socket is blocking */
422 	fd = udev_monitor_get_fd(g_mon);
423 	if ((fflags = fcntl(fd, F_GETFL)) & O_NONBLOCK)
424 		(void) fcntl(fd, F_SETFL, fflags & ~O_NONBLOCK);
425 
426 	/* spawn a thread to monitor events */
427 	if (pthread_create(&g_mon_tid, NULL, zed_udev_monitor, g_mon) != 0) {
428 		udev_monitor_unref(g_mon);
429 		udev_unref(g_udev);
430 		zed_log_msg(LOG_WARNING, "pthread_create failed");
431 		return (-1);
432 	}
433 
434 	pthread_setname_np(g_mon_tid, "udev monitor");
435 	zed_log_msg(LOG_INFO, "zed_disk_event_init");
436 
437 	return (0);
438 }
439 
440 void
441 zed_disk_event_fini(void)
442 {
443 	/* cancel monitor thread at recvmsg() */
444 	(void) pthread_cancel(g_mon_tid);
445 	(void) pthread_join(g_mon_tid, NULL);
446 
447 	/* cleanup udev resources */
448 	udev_monitor_unref(g_mon);
449 	udev_unref(g_udev);
450 
451 	zed_log_msg(LOG_INFO, "zed_disk_event_fini");
452 }
453 
454 #else
455 
456 #include "zed_disk_event.h"
457 
458 int
459 zed_disk_event_init(void)
460 {
461 	return (0);
462 }
463 
464 void
465 zed_disk_event_fini(void)
466 {
467 }
468 
469 #endif /* HAVE_LIBUDEV */
470