Added auto-replace FMA test for the ZFS Test Suite

Also included are updates to auto-online test

Automated auto-replace test to go along with ZED FMA integration
(PR 4673) auto-replace_001.pos works using a scsi_debug device
(the only usable virtual device currently due to whole_disk var
needing to be set)

Functionality for automated FMA auto-replace test to work with
scsi_debug devs:  Some functionality/exceptions needed to be
added for automation of auto-replace to work correctly.

In the test an alias vdev_id rule is added for any scsi_debug
device which sets the phys_path="scsidebug" after a udevadm
trigger command.

A symlink is created for the vdev_id.conf file (in /etc/zfs/ by
default) to be used in-tree for the test suite
(/var/tmp/zfs/vdev_id.conf).  "./scripts/zfs-helpers.sh -i" needs
to be run before fault tests in the ZTS (to use udev rules in-tree)

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Don Brady <don.brady@intel.com>
Reviewed-by: David Quigley <david.quigley@intel.com>
Signed-off-by: Sydney Vanda <sydney.m.vanda@intel.com>
Closes #5944

cmd/zed/agents/zfs_mod.c

@@ -22,7 +22,7 @@
  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012 by Delphix. All rights reserved.
  * Copyright 2014 Nexenta Systems, Inc. All rights reserved.
- * Copyright (c) 2016, Intel Corporation.
+ * Copyright (c) 2016, 2017, Intel Corporation.
  */
 
 /*
@@ -89,6 +89,7 @@
 
 #define	DEV_BYID_PATH	"/dev/disk/by-id/"
 #define	DEV_BYPATH_PATH	"/dev/disk/by-path/"
+#define	DEV_BYVDEV_PATH	"/dev/disk/by-vdev/"
 
 typedef void (*zfs_process_func_t)(zpool_handle_t *, nvlist_t *, boolean_t);
 
@@ -190,6 +191,7 @@ zfs_process_add(zpool_handle_t *zhp, nvlist_t *vdev, boolean_t labeled)
 	char devpath[PATH_MAX];
 	int ret;
 	int is_dm = 0;
+	int is_sd = 0;
 	uint_t c;
 	vdev_stat_t *vs;
 
@@ -258,6 +260,13 @@ zfs_process_add(zpool_handle_t *zhp, nvlist_t *vdev, boolean_t labeled)
 		return;
 	}
 
+	/*
+	 * vdev_id alias rule for using scsi_debug devices (FMA automated
+	 * testing)
+	 */
+	if (strcmp("scsidebug", physpath) == 0)
+		is_sd = 1;
+
 	/*
 	 * If the pool doesn't have the autoreplace property set, then use
 	 * vdev online to trigger a FMA fault by posting an ereport.
@@ -272,10 +281,13 @@ zfs_process_add(zpool_handle_t *zhp, nvlist_t *vdev, boolean_t labeled)
 	}
 
 	/*
-	 * convert physical path into its current device node
+	 * Convert physical path into its current device node.  Rawpath
+	 * needs to be /dev/disk/by-vdev for a scsi_debug device since
+	 * /dev/disk/by-path will not be present.
 	 */
-	(void) snprintf(rawpath, sizeof (rawpath), "%s%s", DEV_BYPATH_PATH,
-	    physpath);
+	(void) snprintf(rawpath, sizeof (rawpath), "%s%s",
+	    is_sd ? DEV_BYVDEV_PATH : DEV_BYPATH_PATH, physpath);
+
 	if (realpath(rawpath, devpath) == NULL && !is_dm) {
 		zed_log_msg(LOG_INFO, "  realpath: %s failed (%s)",
 		    rawpath, strerror(errno));

cmd/zed/zed_disk_event.c

@@ -11,7 +11,7 @@
  */
 
 /*
- * Copyright (c) 2016, Intel Corporation.
+ * Copyright (c) 2016, 2017, Intel Corporation.
  */
 
 #ifdef HAVE_LIBUDEV
@@ -312,6 +312,31 @@ zed_udev_monitor(void *arg)
 			free(tmp2);
 		}
 
+		/*
+		 * Special case an EC_DEV_ADD for scsi_debug devices
+		 *
+		 * These devices require a udevadm trigger command after
+		 * creation in order to register the vdev_id scsidebug alias
+		 * rule (adds a persistent path (phys_path) used for fault
+		 * management automated tests in the ZFS test suite.
+		 *
+		 * After udevadm trigger command, event registers as a "change"
+		 * event but needs to instead be handled as another "add" event
+		 * to allow for disk labeling and partitioning to occur.
+		 */
+		if (strcmp(class, EC_DEV_STATUS) == 0 &&
+		    udev_device_get_property_value(dev, "ID_VDEV") &&
+		    udev_device_get_property_value(dev, "ID_MODEL")) {
+			const char *id_model, *id_model_sd = "scsi_debug";
+
+			id_model = udev_device_get_property_value(dev,
+			    "ID_MODEL");
+			if (strcmp(id_model, id_model_sd) == 0) {
+				class = EC_DEV_ADD;
+				subclass = ESC_DISK;
+			}
+		}
+
 		if ((nvl = dev_event_nvlist(dev)) != NULL) {
 			zed_udev_event(class, subclass, nvl);
 			nvlist_free(nvl);