]> git.proxmox.com Git - mirror_zfs.git/blobdiff - cmd/ztest/ztest.c
OpenZFS 9102 - zfs should be able to initialize storage devices
[mirror_zfs.git] / cmd / ztest / ztest.c
index a4cafcd51bdb903fd1313d84c6690ca9b9d78a55..385984f84dc81ddc77e6aacdc3953b9151b856a8 100644 (file)
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011, 2017 by Delphix. All rights reserved.
+ * Copyright (c) 2011, 2018 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  * Copyright (c) 2013 Steven Hartland. All rights reserved.
  * Copyright (c) 2014 Integros [integros.com]
  * Copyright 2017 Joyent, Inc.
+ * Copyright (c) 2017, Intel Corporation.
  */
 
 /*
 #include <sys/zio.h>
 #include <sys/zil.h>
 #include <sys/zil_impl.h>
-#include <sys/zfs_rlock.h>
 #include <sys/vdev_impl.h>
 #include <sys/vdev_file.h>
+#include <sys/vdev_initialize.h>
 #include <sys/spa_impl.h>
 #include <sys/metaslab_impl.h>
 #include <sys/dsl_prop.h>
 #include <sys/fs/zfs.h>
 #include <zfs_fletcher.h>
 #include <libnvpair.h>
-#include <libzfs.h>
+#include <libzutil.h>
+#include <sys/crypto/icp.h>
 #ifdef __GLIBC__
 #include <execinfo.h> /* for backtrace() */
 #endif
@@ -148,6 +150,12 @@ typedef struct ztest_shared_hdr {
 
 static ztest_shared_hdr_t *ztest_shared_hdr;
 
+enum ztest_class_state {
+       ZTEST_VDEV_CLASS_OFF,
+       ZTEST_VDEV_CLASS_ON,
+       ZTEST_VDEV_CLASS_RND
+};
+
 typedef struct ztest_shared_opts {
        char zo_pool[ZFS_MAX_DATASET_NAME_LEN];
        char zo_dir[ZFS_MAX_DATASET_NAME_LEN];
@@ -170,6 +178,8 @@ typedef struct ztest_shared_opts {
        uint64_t zo_maxloops;
        uint64_t zo_metaslab_force_ganging;
        int zo_mmp_test;
+       int zo_special_vdevs;
+       int zo_dump_dbgmsg;
 } ztest_shared_opts_t;
 
 static const ztest_shared_opts_t ztest_opts_defaults = {
@@ -192,7 +202,8 @@ static const ztest_shared_opts_t ztest_opts_defaults = {
        .zo_init = 1,
        .zo_time = 300,                 /* 5 minutes */
        .zo_maxloops = 50,              /* max loops during spa_freeze() */
-       .zo_metaslab_force_ganging = 32 << 10
+       .zo_metaslab_force_ganging = 64 << 10,
+       .zo_special_vdevs = ZTEST_VDEV_CLASS_RND,
 };
 
 extern uint64_t metaslab_force_ganging;
@@ -202,6 +213,11 @@ extern int metaslab_preload_limit;
 extern boolean_t zfs_compressed_arc_enabled;
 extern int zfs_abd_scatter_enabled;
 extern int dmu_object_alloc_chunk_shift;
+extern boolean_t zfs_force_some_double_word_sm_entries;
+extern unsigned long zio_decompress_fail_fraction;
+extern unsigned long zfs_reconstruct_indirect_damage_fraction;
+extern int zfs_object_remap_one_indirect_delay_ms;
+
 
 static ztest_shared_opts_t *ztest_shared_opts;
 static ztest_shared_opts_t ztest_opts;
@@ -245,6 +261,17 @@ typedef struct bufwad {
        uint64_t        bw_data;
 } bufwad_t;
 
+/*
+ * It would be better to use a rangelock_t per object.  Unfortunately
+ * the rangelock_t is not a drop-in replacement for rl_t, because we
+ * still need to map from object ID to rangelock_t.
+ */
+typedef enum {
+       RL_READER,
+       RL_WRITER,
+       RL_APPEND
+} rl_type_t;
+
 typedef struct rll {
        void            *rll_writer;
        int             rll_readers;
@@ -252,10 +279,12 @@ typedef struct rll {
        kcondvar_t      rll_cv;
 } rll_t;
 
-typedef struct zll {
-       list_t z_list;
-       kmutex_t z_lock;
-} zll_t;
+typedef struct rl {
+       uint64_t        rl_object;
+       uint64_t        rl_offset;
+       uint64_t        rl_size;
+       rll_t           *rl_lock;
+} rl_t;
 
 #define        ZTEST_RANGE_LOCKS       64
 #define        ZTEST_OBJECT_LOCKS      64
@@ -282,13 +311,13 @@ typedef struct ztest_od {
 typedef struct ztest_ds {
        ztest_shared_ds_t *zd_shared;
        objset_t        *zd_os;
-       rwlock_t        zd_zilog_lock;
+       pthread_rwlock_t zd_zilog_lock;
        zilog_t         *zd_zilog;
        ztest_od_t      *zd_od;         /* debugging aid */
        char            zd_name[ZFS_MAX_DATASET_NAME_LEN];
        kmutex_t        zd_dirobj_lock;
        rll_t           zd_object_lock[ZTEST_OBJECT_LOCKS];
-       zll_t           zd_range_lock[ZTEST_RANGE_LOCKS];
+       rll_t           zd_range_lock[ZTEST_RANGE_LOCKS];
 } ztest_ds_t;
 
 /*
@@ -333,18 +362,20 @@ ztest_func_t ztest_fault_inject;
 ztest_func_t ztest_ddt_repair;
 ztest_func_t ztest_dmu_snapshot_hold;
 ztest_func_t ztest_mmp_enable_disable;
-ztest_func_t ztest_spa_rename;
 ztest_func_t ztest_scrub;
 ztest_func_t ztest_dsl_dataset_promote_busy;
 ztest_func_t ztest_vdev_attach_detach;
 ztest_func_t ztest_vdev_LUN_growth;
 ztest_func_t ztest_vdev_add_remove;
+ztest_func_t ztest_vdev_class_add;
 ztest_func_t ztest_vdev_aux_add_remove;
 ztest_func_t ztest_split_pool;
 ztest_func_t ztest_reguid;
 ztest_func_t ztest_spa_upgrade;
 ztest_func_t ztest_device_removal;
 ztest_func_t ztest_remap_blocks;
+ztest_func_t ztest_spa_checkpoint_create_discard;
+ztest_func_t ztest_initialize;
 ztest_func_t ztest_fletcher;
 ztest_func_t ztest_fletcher_incr;
 ztest_func_t ztest_verify_dnode_bt;
@@ -387,16 +418,18 @@ ztest_info_t ztest_info[] = {
        ZTI_INIT(ztest_dmu_snapshot_hold, 1, &zopt_sometimes),
        ZTI_INIT(ztest_mmp_enable_disable, 1, &zopt_sometimes),
        ZTI_INIT(ztest_reguid, 1, &zopt_rarely),
-       ZTI_INIT(ztest_spa_rename, 1, &zopt_rarely),
        ZTI_INIT(ztest_scrub, 1, &zopt_rarely),
        ZTI_INIT(ztest_spa_upgrade, 1, &zopt_rarely),
        ZTI_INIT(ztest_dsl_dataset_promote_busy, 1, &zopt_rarely),
        ZTI_INIT(ztest_vdev_attach_detach, 1, &zopt_sometimes),
        ZTI_INIT(ztest_vdev_LUN_growth, 1, &zopt_rarely),
        ZTI_INIT(ztest_vdev_add_remove, 1, &ztest_opts.zo_vdevtime),
+       ZTI_INIT(ztest_vdev_class_add, 1, &ztest_opts.zo_vdevtime),
        ZTI_INIT(ztest_vdev_aux_add_remove, 1, &ztest_opts.zo_vdevtime),
        ZTI_INIT(ztest_device_removal, 1, &zopt_sometimes),
        ZTI_INIT(ztest_remap_blocks, 1, &zopt_sometimes),
+       ZTI_INIT(ztest_spa_checkpoint_create_discard, 1, &zopt_rarely),
+       ZTI_INIT(ztest_initialize, 1, &zopt_sometimes),
        ZTI_INIT(ztest_fletcher, 1, &zopt_rarely),
        ZTI_INIT(ztest_fletcher_incr, 1, &zopt_rarely),
        ZTI_INIT(ztest_verify_dnode_bt, 1, &zopt_sometimes),
@@ -446,6 +479,7 @@ static ztest_ds_t *ztest_ds;
 
 static kmutex_t ztest_vdev_lock;
 static boolean_t ztest_device_removal_active = B_FALSE;
+static kmutex_t ztest_checkpoint_lock;
 
 /*
  * The ztest_name_lock protects the pool and dataset namespace used by
@@ -453,10 +487,9 @@ static boolean_t ztest_device_removal_active = B_FALSE;
  * this lock as writer. Grabbing the lock as reader will ensure that the
  * namespace does not change while the lock is held.
  */
-static rwlock_t ztest_name_lock;
+static pthread_rwlock_t ztest_name_lock;
 
 static boolean_t ztest_dump_core = B_TRUE;
-static boolean_t ztest_dump_debug_buffer = B_FALSE;
 static boolean_t ztest_exiting;
 
 /* Global commit callback list */
@@ -478,9 +511,6 @@ static int zc_cb_counter = 0;
  */
 #define        ZTEST_COMMIT_CB_THRESH  (TXG_CONCURRENT_STATES + 1000)
 
-extern uint64_t metaslab_gang_bang;
-extern uint64_t metaslab_df_alloc_threshold;
-
 enum ztest_object {
        ZTEST_META_DNODE = 0,
        ZTEST_DIROBJ,
@@ -508,10 +538,16 @@ _umem_logging_init(void)
 static void
 dump_debug_buffer(void)
 {
-       if (!ztest_dump_debug_buffer)
+       ssize_t ret __attribute__((unused));
+
+       if (!ztest_opts.zo_dump_dbgmsg)
                return;
 
-       (void) printf("\n");
+       /*
+        * We use write() instead of printf() so that this function
+        * is safe to call from a signal handler.
+        */
+       ret = write(STDOUT_FILENO, "\n", 1);
        zfs_dbgmsg_print("ztest");
 }
 
@@ -566,10 +602,11 @@ fatal(int do_perror, char *message, ...)
        (void) fprintf(stderr, "%s\n", buf);
        fatal_msg = buf;                        /* to ease debugging */
 
-       dump_debug_buffer();
-
        if (ztest_dump_core)
                abort();
+       else
+               dump_debug_buffer();
+
        exit(3);
 }
 
@@ -663,6 +700,7 @@ usage(boolean_t requested)
            "\t[-F freezeloops (default: %llu)] max loops in spa_freeze()\n"
            "\t[-P passtime (default: %llu sec)] time per pass\n"
            "\t[-B alt_ztest (default: <none>)] alternate ztest path\n"
+           "\t[-C vdev class state (default: random)] special=on|off|random\n"
            "\t[-o variable=value] ... set global variable to an unsigned\n"
            "\t    32-bit integer value\n"
            "\t[-G dump zfs_dbgmsg buffer before exiting due to an error\n"
@@ -688,6 +726,46 @@ usage(boolean_t requested)
        exit(requested ? 0 : 1);
 }
 
+
+static void
+ztest_parse_name_value(const char *input, ztest_shared_opts_t *zo)
+{
+       char name[32];
+       char *value;
+       int state = ZTEST_VDEV_CLASS_RND;
+
+       (void) strlcpy(name, input, sizeof (name));
+
+       value = strchr(name, '=');
+       if (value == NULL) {
+               (void) fprintf(stderr, "missing value in property=value "
+                   "'-C' argument (%s)\n", input);
+               usage(B_FALSE);
+       }
+       *(value) = '\0';
+       value++;
+
+       if (strcmp(value, "on") == 0) {
+               state = ZTEST_VDEV_CLASS_ON;
+       } else if (strcmp(value, "off") == 0) {
+               state = ZTEST_VDEV_CLASS_OFF;
+       } else if (strcmp(value, "random") == 0) {
+               state = ZTEST_VDEV_CLASS_RND;
+       } else {
+               (void) fprintf(stderr, "invalid property value '%s'\n", value);
+               usage(B_FALSE);
+       }
+
+       if (strcmp(name, "special") == 0) {
+               zo->zo_special_vdevs = state;
+       } else {
+               (void) fprintf(stderr, "invalid property name '%s'\n", name);
+               usage(B_FALSE);
+       }
+       if (zo->zo_verbose >= 3)
+               (void) printf("%s vdev state is '%s'\n", name, value);
+}
+
 static void
 process_options(int argc, char **argv)
 {
@@ -701,7 +779,7 @@ process_options(int argc, char **argv)
        bcopy(&ztest_opts_defaults, zo, sizeof (*zo));
 
        while ((opt = getopt(argc, argv,
-           "v:s:a:m:r:R:d:t:g:i:k:p:f:MVET:P:hF:B:o:G")) != EOF) {
+           "v:s:a:m:r:R:d:t:g:i:k:p:f:MVET:P:hF:B:C:o:G")) != EOF) {
                value = 0;
                switch (opt) {
                case 'v':
@@ -792,12 +870,15 @@ process_options(int argc, char **argv)
                case 'B':
                        (void) strlcpy(altdir, optarg, sizeof (altdir));
                        break;
+               case 'C':
+                       ztest_parse_name_value(optarg, zo);
+                       break;
                case 'o':
                        if (set_global_var(optarg) != 0)
                                usage(B_FALSE);
                        break;
                case 'G':
-                       ztest_dump_debug_buffer = B_TRUE;
+                       zo->zo_dump_dbgmsg = 1;
                        break;
                case 'h':
                        usage(B_TRUE);
@@ -1019,13 +1100,16 @@ make_vdev_mirror(char *path, char *aux, char *pool, size_t size,
 
 static nvlist_t *
 make_vdev_root(char *path, char *aux, char *pool, size_t size, uint64_t ashift,
-    int log, int r, int m, int t)
+    const char *class, int r, int m, int t)
 {
        nvlist_t *root, **child;
        int c;
+       boolean_t log;
 
        ASSERT(t > 0);
 
+       log = (class != NULL && strcmp(class, "log") == 0);
+
        child = umem_alloc(t * sizeof (nvlist_t *), UMEM_NOFAIL);
 
        for (c = 0; c < t; c++) {
@@ -1033,6 +1117,12 @@ make_vdev_root(char *path, char *aux, char *pool, size_t size, uint64_t ashift,
                    r, m);
                VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_IS_LOG,
                    log) == 0);
+
+               if (class != NULL && class[0] != '\0') {
+                       ASSERT(m > 1 || log);   /* expecting a mirror */
+                       VERIFY(nvlist_add_string(child[c],
+                           ZPOOL_CONFIG_ALLOCATION_BIAS, class) == 0);
+               }
        }
 
        VERIFY(nvlist_alloc(&root, NV_UNIQUE_NAME, 0) == 0);
@@ -1072,6 +1162,8 @@ ztest_random_spa_version(uint64_t initial_version)
 static int
 ztest_random_blocksize(void)
 {
+       ASSERT(ztest_spa->spa_max_ashift != 0);
+
        /*
         * Choose a block size >= the ashift.
         * If the SPA supports new MAXBLOCKSIZE, test up to 1MB blocks.
@@ -1217,19 +1309,18 @@ ztest_dmu_objset_own(const char *name, dmu_objset_type_t type,
     boolean_t readonly, boolean_t decrypt, void *tag, objset_t **osp)
 {
        int err;
+       char *cp = NULL;
+       char ddname[ZFS_MAX_DATASET_NAME_LEN];
+
+       strcpy(ddname, name);
+       cp = strchr(ddname, '@');
+       if (cp != NULL)
+               *cp = '\0';
 
        err = dmu_objset_own(name, type, readonly, decrypt, tag, osp);
-       if (decrypt && err == EACCES) {
-               char ddname[ZFS_MAX_DATASET_NAME_LEN];
+       while (decrypt && err == EACCES) {
                dsl_crypto_params_t *dcp;
                nvlist_t *crypto_args = fnvlist_alloc();
-               char *cp = NULL;
-
-               /* spa_keystore_load_wkey() expects a dsl dir name */
-               strcpy(ddname, name);
-               cp = strchr(ddname, '@');
-               if (cp != NULL)
-                       *cp = '\0';
 
                fnvlist_add_uint8_array(crypto_args, "wkeydata",
                    (uint8_t *)ztest_wkeydata, WRAPPING_KEY_LEN);
@@ -1239,108 +1330,30 @@ ztest_dmu_objset_own(const char *name, dmu_objset_type_t type,
                dsl_crypto_params_free(dcp, B_FALSE);
                fnvlist_free(crypto_args);
 
-               if (err != 0)
-                       return (err);
-
-               err = dmu_objset_own(name, type, readonly, decrypt, tag, osp);
-       }
-
-       return (err);
-}
-
-
-/*
- * Object and range lock mechanics
- */
-typedef struct {
-       list_node_t z_lnode;
-       refcount_t z_refcnt;
-       uint64_t z_object;
-       zfs_rlock_t z_range_lock;
-} ztest_znode_t;
-
-typedef struct {
-       rl_t *z_rl;
-       ztest_znode_t *z_ztznode;
-} ztest_zrl_t;
-
-static ztest_znode_t *
-ztest_znode_init(uint64_t object)
-{
-       ztest_znode_t *zp = umem_alloc(sizeof (*zp), UMEM_NOFAIL);
-
-       list_link_init(&zp->z_lnode);
-       refcount_create(&zp->z_refcnt);
-       zp->z_object = object;
-       zfs_rlock_init(&zp->z_range_lock);
-
-       return (zp);
-}
-
-static void
-ztest_znode_fini(ztest_znode_t *zp)
-{
-       ASSERT(refcount_is_zero(&zp->z_refcnt));
-       zfs_rlock_destroy(&zp->z_range_lock);
-       zp->z_object = 0;
-       refcount_destroy(&zp->z_refcnt);
-       list_link_init(&zp->z_lnode);
-       umem_free(zp, sizeof (*zp));
-}
-
-static void
-ztest_zll_init(zll_t *zll)
-{
-       mutex_init(&zll->z_lock, NULL, MUTEX_DEFAULT, NULL);
-       list_create(&zll->z_list, sizeof (ztest_znode_t),
-           offsetof(ztest_znode_t, z_lnode));
-}
-
-static void
-ztest_zll_destroy(zll_t *zll)
-{
-       list_destroy(&zll->z_list);
-       mutex_destroy(&zll->z_lock);
-}
+               if (err == EINVAL) {
+                       /*
+                        * We couldn't load a key for this dataset so try
+                        * the parent. This loop will eventually hit the
+                        * encryption root since ztest only makes clones
+                        * as children of their origin datasets.
+                        */
+                       cp = strrchr(ddname, '/');
+                       if (cp == NULL)
+                               return (err);
 
-#define        RL_TAG "range_lock"
-static ztest_znode_t *
-ztest_znode_get(ztest_ds_t *zd, uint64_t object)
-{
-       zll_t *zll = &zd->zd_range_lock[object & (ZTEST_OBJECT_LOCKS - 1)];
-       ztest_znode_t *zp = NULL;
-       mutex_enter(&zll->z_lock);
-       for (zp = list_head(&zll->z_list); (zp);
-           zp = list_next(&zll->z_list, zp)) {
-               if (zp->z_object == object) {
-                       refcount_add(&zp->z_refcnt, RL_TAG);
+                       *cp = '\0';
+                       err = EACCES;
+                       continue;
+               } else if (err != 0) {
                        break;
                }
-       }
-       if (zp == NULL) {
-               zp = ztest_znode_init(object);
-               refcount_add(&zp->z_refcnt, RL_TAG);
-               list_insert_head(&zll->z_list, zp);
-       }
-       mutex_exit(&zll->z_lock);
-       return (zp);
-}
 
-static void
-ztest_znode_put(ztest_ds_t *zd, ztest_znode_t *zp)
-{
-       zll_t *zll = NULL;
-       ASSERT3U(zp->z_object, !=, 0);
-       zll = &zd->zd_range_lock[zp->z_object & (ZTEST_OBJECT_LOCKS - 1)];
-       mutex_enter(&zll->z_lock);
-       refcount_remove(&zp->z_refcnt, RL_TAG);
-       if (refcount_is_zero(&zp->z_refcnt)) {
-               list_remove(&zll->z_list, zp);
-               ztest_znode_fini(zp);
+               err = dmu_objset_own(name, type, readonly, decrypt, tag, osp);
+               break;
        }
-       mutex_exit(&zll->z_lock);
-}
 
+       return (err);
+}
 
 static void
 ztest_rll_init(rll_t *rll)
@@ -1414,37 +1427,33 @@ ztest_object_unlock(ztest_ds_t *zd, uint64_t object)
        ztest_rll_unlock(rll);
 }
 
-static ztest_zrl_t *
-ztest_zrl_init(rl_t *rl, ztest_znode_t *zp)
-{
-       ztest_zrl_t *zrl = umem_alloc(sizeof (*zrl), UMEM_NOFAIL);
-       zrl->z_rl = rl;
-       zrl->z_ztznode = zp;
-       return (zrl);
-}
-
-static void
-ztest_zrl_fini(ztest_zrl_t *zrl)
-{
-       umem_free(zrl, sizeof (*zrl));
-}
-
-static ztest_zrl_t *
+static rl_t *
 ztest_range_lock(ztest_ds_t *zd, uint64_t object, uint64_t offset,
     uint64_t size, rl_type_t type)
 {
-       ztest_znode_t *zp = ztest_znode_get(zd, object);
-       rl_t *rl = zfs_range_lock(&zp->z_range_lock, offset,
-           size, type);
-       return (ztest_zrl_init(rl, zp));
+       uint64_t hash = object ^ (offset % (ZTEST_RANGE_LOCKS + 1));
+       rll_t *rll = &zd->zd_range_lock[hash & (ZTEST_RANGE_LOCKS - 1)];
+       rl_t *rl;
+
+       rl = umem_alloc(sizeof (*rl), UMEM_NOFAIL);
+       rl->rl_object = object;
+       rl->rl_offset = offset;
+       rl->rl_size = size;
+       rl->rl_lock = rll;
+
+       ztest_rll_lock(rll, type);
+
+       return (rl);
 }
 
 static void
-ztest_range_unlock(ztest_ds_t *zd, ztest_zrl_t *zrl)
+ztest_range_unlock(rl_t *rl)
 {
-       zfs_range_unlock(zrl->z_rl);
-       ztest_znode_put(zd, zrl->z_ztznode);
-       ztest_zrl_fini(zrl);
+       rll_t *rll = rl->rl_lock;
+
+       ztest_rll_unlock(rll);
+
+       umem_free(rl, sizeof (*rl));
 }
 
 static void
@@ -1459,14 +1468,14 @@ ztest_zd_init(ztest_ds_t *zd, ztest_shared_ds_t *szd, objset_t *os)
        if (zd->zd_shared != NULL)
                zd->zd_shared->zd_seq = 0;
 
-       VERIFY(rwlock_init(&zd->zd_zilog_lock, USYNC_THREAD, NULL) == 0);
+       VERIFY0(pthread_rwlock_init(&zd->zd_zilog_lock, NULL));
        mutex_init(&zd->zd_dirobj_lock, NULL, MUTEX_DEFAULT, NULL);
 
        for (l = 0; l < ZTEST_OBJECT_LOCKS; l++)
                ztest_rll_init(&zd->zd_object_lock[l]);
 
        for (l = 0; l < ZTEST_RANGE_LOCKS; l++)
-               ztest_zll_init(&zd->zd_range_lock[l]);
+               ztest_rll_init(&zd->zd_range_lock[l]);
 }
 
 static void
@@ -1475,13 +1484,13 @@ ztest_zd_fini(ztest_ds_t *zd)
        int l;
 
        mutex_destroy(&zd->zd_dirobj_lock);
-       (void) rwlock_destroy(&zd->zd_zilog_lock);
+       (void) pthread_rwlock_destroy(&zd->zd_zilog_lock);
 
        for (l = 0; l < ZTEST_OBJECT_LOCKS; l++)
                ztest_rll_destroy(&zd->zd_object_lock[l]);
 
        for (l = 0; l < ZTEST_RANGE_LOCKS; l++)
-               ztest_zll_destroy(&zd->zd_range_lock[l]);
+               ztest_rll_destroy(&zd->zd_range_lock[l]);
 }
 
 #define        TXG_MIGHTWAIT   (ztest_random(10) == 0 ? TXG_NOWAIT : TXG_WAIT)
@@ -1897,7 +1906,7 @@ ztest_replay_write(void *arg1, void *arg2, boolean_t byteswap)
        dmu_tx_t *tx;
        dmu_buf_t *db;
        arc_buf_t *abuf = NULL;
-       ztest_zrl_t *rl;
+       rl_t *rl;
 
        if (byteswap)
                byteswap_uint64_array(lr, sizeof (*lr));
@@ -1946,7 +1955,7 @@ ztest_replay_write(void *arg1, void *arg2, boolean_t byteswap)
                if (abuf != NULL)
                        dmu_return_arcbuf(abuf);
                dmu_buf_rele(db, FTAG);
-               ztest_range_unlock(zd, rl);
+               ztest_range_unlock(rl);
                ztest_object_unlock(zd, lr->lr_foid);
                return (ENOSPC);
        }
@@ -2004,7 +2013,7 @@ ztest_replay_write(void *arg1, void *arg2, boolean_t byteswap)
 
        dmu_tx_commit(tx);
 
-       ztest_range_unlock(zd, rl);
+       ztest_range_unlock(rl);
        ztest_object_unlock(zd, lr->lr_foid);
 
        return (0);
@@ -2018,7 +2027,7 @@ ztest_replay_truncate(void *arg1, void *arg2, boolean_t byteswap)
        objset_t *os = zd->zd_os;
        dmu_tx_t *tx;
        uint64_t txg;
-       ztest_zrl_t *rl;
+       rl_t *rl;
 
        if (byteswap)
                byteswap_uint64_array(lr, sizeof (*lr));
@@ -2033,7 +2042,7 @@ ztest_replay_truncate(void *arg1, void *arg2, boolean_t byteswap)
 
        txg = ztest_tx_assign(tx, TXG_WAIT, FTAG);
        if (txg == 0) {
-               ztest_range_unlock(zd, rl);
+               ztest_range_unlock(rl);
                ztest_object_unlock(zd, lr->lr_foid);
                return (ENOSPC);
        }
@@ -2045,7 +2054,7 @@ ztest_replay_truncate(void *arg1, void *arg2, boolean_t byteswap)
 
        dmu_tx_commit(tx);
 
-       ztest_range_unlock(zd, rl);
+       ztest_range_unlock(rl);
        ztest_object_unlock(zd, lr->lr_foid);
 
        return (0);
@@ -2152,30 +2161,21 @@ zil_replay_func_t *ztest_replay_vector[TX_MAX_TYPE] = {
 /*
  * ZIL get_data callbacks
  */
-typedef struct ztest_zgd_private {
-       ztest_ds_t *z_zd;
-       ztest_zrl_t *z_rl;
-       uint64_t z_object;
-} ztest_zgd_private_t;
 
+/* ARGSUSED */
 static void
 ztest_get_done(zgd_t *zgd, int error)
 {
-       ztest_zgd_private_t *zzp = zgd->zgd_private;
-       ztest_ds_t *zd = zzp->z_zd;
-       uint64_t object = zzp->z_object;
+       ztest_ds_t *zd = zgd->zgd_private;
+       uint64_t object = ((rl_t *)zgd->zgd_lr)->rl_object;
 
        if (zgd->zgd_db)
                dmu_buf_rele(zgd->zgd_db, zgd);
 
-       ztest_range_unlock(zd, zzp->z_rl);
+       ztest_range_unlock((rl_t *)zgd->zgd_lr);
        ztest_object_unlock(zd, object);
 
-       if (error == 0 && zgd->zgd_bp)
-               zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp);
-
        umem_free(zgd, sizeof (*zgd));
-       umem_free(zzp, sizeof (*zzp));
 }
 
 static int
@@ -2193,7 +2193,6 @@ ztest_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb,
        dmu_buf_t *db;
        zgd_t *zgd;
        int error;
-       ztest_zgd_private_t *zgd_private;
 
        ASSERT3P(lwb, !=, NULL);
        ASSERT3P(zio, !=, NULL);
@@ -2220,15 +2219,11 @@ ztest_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb,
 
        zgd = umem_zalloc(sizeof (*zgd), UMEM_NOFAIL);
        zgd->zgd_lwb = lwb;
-       zgd_private = umem_zalloc(sizeof (ztest_zgd_private_t), UMEM_NOFAIL);
-       zgd_private->z_zd = zd;
-       zgd_private->z_object = object;
-       zgd->zgd_private = zgd_private;
+       zgd->zgd_private = zd;
 
        if (buf != NULL) {      /* immediate write */
-               zgd_private->z_rl = ztest_range_lock(zd, object, offset, size,
-                   RL_READER);
-               zgd->zgd_rl = zgd_private->z_rl->z_rl;
+               zgd->zgd_lr = (struct locked_range *)ztest_range_lock(zd,
+                   object, offset, size, RL_READER);
 
                error = dmu_read(os, object, offset, size, buf,
                    DMU_READ_NO_PREFETCH);
@@ -2242,9 +2237,8 @@ ztest_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb,
                        offset = 0;
                }
 
-               zgd_private->z_rl = ztest_range_lock(zd, object, offset, size,
-                   RL_READER);
-               zgd->zgd_rl = zgd_private->z_rl->z_rl;
+               zgd->zgd_lr = (struct locked_range *)ztest_range_lock(zd,
+                   object, offset, size, RL_READER);
 
                error = dmu_buf_hold(os, object, offset, zgd, &db,
                    DMU_READ_NO_PREFETCH);
@@ -2490,7 +2484,7 @@ ztest_prealloc(ztest_ds_t *zd, uint64_t object, uint64_t offset, uint64_t size)
        objset_t *os = zd->zd_os;
        dmu_tx_t *tx;
        uint64_t txg;
-       ztest_zrl_t *rl;
+       rl_t *rl;
 
        txg_wait_synced(dmu_objset_pool(os), 0);
 
@@ -2511,7 +2505,7 @@ ztest_prealloc(ztest_ds_t *zd, uint64_t object, uint64_t offset, uint64_t size)
                (void) dmu_free_long_range(os, object, offset, size);
        }
 
-       ztest_range_unlock(zd, rl);
+       ztest_range_unlock(rl);
        ztest_object_unlock(zd, object);
 }
 
@@ -2536,7 +2530,7 @@ ztest_io(ztest_ds_t *zd, uint64_t object, uint64_t offset)
        if (ztest_random(2) == 0)
                io_type = ZTEST_IO_WRITE_TAG;
 
-       (void) rw_rdlock(&zd->zd_zilog_lock);
+       (void) pthread_rwlock_rdlock(&zd->zd_zilog_lock);
 
        switch (io_type) {
 
@@ -2576,7 +2570,7 @@ ztest_io(ztest_ds_t *zd, uint64_t object, uint64_t offset)
                break;
 
        case ZTEST_IO_REWRITE:
-               (void) rw_rdlock(&ztest_name_lock);
+               (void) pthread_rwlock_rdlock(&ztest_name_lock);
                err = ztest_dsl_prop_set_uint64(zd->zd_name,
                    ZFS_PROP_CHECKSUM, spa_dedup_checksum(ztest_spa),
                    B_FALSE);
@@ -2586,7 +2580,7 @@ ztest_io(ztest_ds_t *zd, uint64_t object, uint64_t offset)
                    ztest_random_dsl_prop(ZFS_PROP_COMPRESSION),
                    B_FALSE);
                VERIFY(err == 0 || err == ENOSPC);
-               (void) rw_unlock(&ztest_name_lock);
+               (void) pthread_rwlock_unlock(&ztest_name_lock);
 
                VERIFY0(dmu_read(zd->zd_os, object, offset, blocksize, data,
                    DMU_READ_NO_PREFETCH));
@@ -2595,7 +2589,7 @@ ztest_io(ztest_ds_t *zd, uint64_t object, uint64_t offset)
                break;
        }
 
-       (void) rw_unlock(&zd->zd_zilog_lock);
+       (void) pthread_rwlock_unlock(&zd->zd_zilog_lock);
 
        umem_free(data, blocksize);
 }
@@ -2653,7 +2647,7 @@ ztest_zil_commit(ztest_ds_t *zd, uint64_t id)
 {
        zilog_t *zilog = zd->zd_zilog;
 
-       (void) rw_rdlock(&zd->zd_zilog_lock);
+       (void) pthread_rwlock_rdlock(&zd->zd_zilog_lock);
 
        zil_commit(zilog, ztest_random(ZTEST_OBJECTS));
 
@@ -2668,7 +2662,7 @@ ztest_zil_commit(ztest_ds_t *zd, uint64_t id)
        zd->zd_shared->zd_seq = zilog->zl_commit_lr_seq;
        mutex_exit(&zilog->zl_lock);
 
-       (void) rw_unlock(&zd->zd_zilog_lock);
+       (void) pthread_rwlock_unlock(&zd->zd_zilog_lock);
 }
 
 /*
@@ -2682,13 +2676,20 @@ ztest_zil_remount(ztest_ds_t *zd, uint64_t id)
 {
        objset_t *os = zd->zd_os;
 
+       /*
+        * We hold the ztest_vdev_lock so we don't cause problems with
+        * other threads that wish to remove a log device, such as
+        * ztest_device_removal().
+        */
+       mutex_enter(&ztest_vdev_lock);
+
        /*
         * We grab the zd_dirobj_lock to ensure that no other thread is
         * updating the zil (i.e. adding in-memory log records) and the
         * zd_zilog_lock to block any I/O.
         */
        mutex_enter(&zd->zd_dirobj_lock);
-       (void) rw_wrlock(&zd->zd_zilog_lock);
+       (void) pthread_rwlock_wrlock(&zd->zd_zilog_lock);
 
        /* zfsvfs_teardown() */
        zil_close(zd->zd_zilog);
@@ -2697,8 +2698,9 @@ ztest_zil_remount(ztest_ds_t *zd, uint64_t id)
        VERIFY(zil_open(os, ztest_get_data) == zd->zd_zilog);
        zil_replay(os, zd, ztest_replay_vector);
 
-       (void) rw_unlock(&zd->zd_zilog_lock);
+       (void) pthread_rwlock_unlock(&zd->zd_zilog_lock);
        mutex_exit(&zd->zd_dirobj_lock);
+       mutex_exit(&ztest_vdev_lock);
 }
 
 /*
@@ -2719,7 +2721,7 @@ ztest_spa_create_destroy(ztest_ds_t *zd, uint64_t id)
        /*
         * Attempt to create using a bad file.
         */
-       nvroot = make_vdev_root("/dev/bogus", NULL, NULL, 0, 0, 0, 0, 0, 1);
+       nvroot = make_vdev_root("/dev/bogus", NULL, NULL, 0, 0, NULL, 0, 0, 1);
        VERIFY3U(ENOENT, ==,
            spa_create("ztest_bad_file", nvroot, NULL, NULL, NULL));
        nvlist_free(nvroot);
@@ -2727,7 +2729,7 @@ ztest_spa_create_destroy(ztest_ds_t *zd, uint64_t id)
        /*
         * Attempt to create using a bad mirror.
         */
-       nvroot = make_vdev_root("/dev/bogus", NULL, NULL, 0, 0, 0, 0, 2, 1);
+       nvroot = make_vdev_root("/dev/bogus", NULL, NULL, 0, 0, NULL, 0, 2, 1);
        VERIFY3U(ENOENT, ==,
            spa_create("ztest_bad_mirror", nvroot, NULL, NULL, NULL));
        nvlist_free(nvroot);
@@ -2736,8 +2738,8 @@ ztest_spa_create_destroy(ztest_ds_t *zd, uint64_t id)
         * Attempt to create an existing pool.  It shouldn't matter
         * what's in the nvroot; we should fail with EEXIST.
         */
-       (void) rw_rdlock(&ztest_name_lock);
-       nvroot = make_vdev_root("/dev/bogus", NULL, NULL, 0, 0, 0, 0, 0, 1);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
+       nvroot = make_vdev_root("/dev/bogus", NULL, NULL, 0, 0, NULL, 0, 0, 1);
        VERIFY3U(EEXIST, ==,
            spa_create(zo->zo_pool, nvroot, NULL, NULL, NULL));
        nvlist_free(nvroot);
@@ -2745,7 +2747,7 @@ ztest_spa_create_destroy(ztest_ds_t *zd, uint64_t id)
        VERIFY3U(EBUSY, ==, spa_destroy(zo->zo_pool));
        spa_close(spa, FTAG);
 
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 }
 
 /*
@@ -2765,6 +2767,8 @@ ztest_mmp_enable_disable(ztest_ds_t *zd, uint64_t id)
        spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
        mutex_enter(&spa->spa_props_lock);
 
+       zfs_multihost_fail_intervals = 0;
+
        if (!spa_multihost(spa)) {
                spa->spa_multihost = B_TRUE;
                mmp_thread_start(spa);
@@ -2811,7 +2815,7 @@ ztest_spa_upgrade(ztest_ds_t *zd, uint64_t id)
        (void) spa_destroy(name);
 
        nvroot = make_vdev_root(NULL, NULL, name, ztest_opts.zo_vdev_size, 0,
-           0, ztest_opts.zo_raidz, ztest_opts.zo_mirrors, 1);
+           NULL, ztest_opts.zo_raidz, ztest_opts.zo_mirrors, 1);
 
        /*
         * If we're configuring a RAIDZ device then make sure that the
@@ -2864,6 +2868,62 @@ ztest_spa_upgrade(ztest_ds_t *zd, uint64_t id)
        mutex_exit(&ztest_vdev_lock);
 }
 
+static void
+ztest_spa_checkpoint(spa_t *spa)
+{
+       ASSERT(MUTEX_HELD(&ztest_checkpoint_lock));
+
+       int error = spa_checkpoint(spa->spa_name);
+
+       switch (error) {
+       case 0:
+       case ZFS_ERR_DEVRM_IN_PROGRESS:
+       case ZFS_ERR_DISCARDING_CHECKPOINT:
+       case ZFS_ERR_CHECKPOINT_EXISTS:
+               break;
+       case ENOSPC:
+               ztest_record_enospc(FTAG);
+               break;
+       default:
+               fatal(0, "spa_checkpoint(%s) = %d", spa->spa_name, error);
+       }
+}
+
+static void
+ztest_spa_discard_checkpoint(spa_t *spa)
+{
+       ASSERT(MUTEX_HELD(&ztest_checkpoint_lock));
+
+       int error = spa_checkpoint_discard(spa->spa_name);
+
+       switch (error) {
+       case 0:
+       case ZFS_ERR_DISCARDING_CHECKPOINT:
+       case ZFS_ERR_NO_CHECKPOINT:
+               break;
+       default:
+               fatal(0, "spa_discard_checkpoint(%s) = %d",
+                   spa->spa_name, error);
+       }
+
+}
+
+/* ARGSUSED */
+void
+ztest_spa_checkpoint_create_discard(ztest_ds_t *zd, uint64_t id)
+{
+       spa_t *spa = ztest_spa;
+
+       mutex_enter(&ztest_checkpoint_lock);
+       if (ztest_random(2) == 0) {
+               ztest_spa_checkpoint(spa);
+       } else {
+               ztest_spa_discard_checkpoint(spa);
+       }
+       mutex_exit(&ztest_checkpoint_lock);
+}
+
+
 static vdev_t *
 vdev_lookup_by_path(vdev_t *vd, const char *path)
 {
@@ -2929,10 +2989,16 @@ ztest_vdev_add_remove(ztest_ds_t *zd, uint64_t id)
         * If we have slogs then remove them 1/4 of the time.
         */
        if (spa_has_slogs(spa) && ztest_random(4) == 0) {
+               metaslab_group_t *mg;
+
                /*
-                * Grab the guid from the head of the log class rotor.
+                * find the first real slog in log allocation class
                 */
-               guid = spa_log_class(spa)->mc_rotor->mg_vd->vdev_guid;
+               mg =  spa_log_class(spa)->mc_rotor;
+               while (!mg->mg_vd->vdev_islog)
+                       mg = mg->mg_next;
+
+               guid = mg->mg_vd->vdev_guid;
 
                spa_config_exit(spa, SCL_VDEV, FTAG);
 
@@ -2944,33 +3010,123 @@ ztest_vdev_add_remove(ztest_ds_t *zd, uint64_t id)
                 * dsl_destroy_head() to fail with EBUSY thus
                 * leaving the dataset in an inconsistent state.
                 */
-               rw_wrlock(&ztest_name_lock);
+               pthread_rwlock_wrlock(&ztest_name_lock);
                error = spa_vdev_remove(spa, guid, B_FALSE);
-               rw_unlock(&ztest_name_lock);
-
-               if (error && error != EEXIST)
+               pthread_rwlock_unlock(&ztest_name_lock);
+
+               switch (error) {
+               case 0:
+               case EEXIST:    /* Generic zil_reset() error */
+               case EBUSY:     /* Replay required */
+               case EACCES:    /* Crypto key not loaded */
+               case ZFS_ERR_CHECKPOINT_EXISTS:
+               case ZFS_ERR_DISCARDING_CHECKPOINT:
+                       break;
+               default:
                        fatal(0, "spa_vdev_remove() = %d", error);
+               }
        } else {
                spa_config_exit(spa, SCL_VDEV, FTAG);
 
                /*
-                * Make 1/4 of the devices be log devices.
+                * Make 1/4 of the devices be log devices
                 */
                nvroot = make_vdev_root(NULL, NULL, NULL,
-                   ztest_opts.zo_vdev_size, 0,
-                   ztest_random(4) == 0, ztest_opts.zo_raidz,
-                   zs->zs_mirrors, 1);
+                   ztest_opts.zo_vdev_size, 0, (ztest_random(4) == 0) ?
+                   "log" : NULL, ztest_opts.zo_raidz, zs->zs_mirrors, 1);
 
                error = spa_vdev_add(spa, nvroot);
                nvlist_free(nvroot);
 
-               if (error == ENOSPC)
+               switch (error) {
+               case 0:
+                       break;
+               case ENOSPC:
                        ztest_record_enospc("spa_vdev_add");
-               else if (error != 0)
+                       break;
+               default:
                        fatal(0, "spa_vdev_add() = %d", error);
+               }
+       }
+
+       mutex_exit(&ztest_vdev_lock);
+}
+
+/* ARGSUSED */
+void
+ztest_vdev_class_add(ztest_ds_t *zd, uint64_t id)
+{
+       ztest_shared_t *zs = ztest_shared;
+       spa_t *spa = ztest_spa;
+       uint64_t leaves;
+       nvlist_t *nvroot;
+       const char *class = (ztest_random(2) == 0) ?
+           VDEV_ALLOC_BIAS_SPECIAL : VDEV_ALLOC_BIAS_DEDUP;
+       int error;
+
+       /*
+        * By default add a special vdev 50% of the time
+        */
+       if ((ztest_opts.zo_special_vdevs == ZTEST_VDEV_CLASS_OFF) ||
+           (ztest_opts.zo_special_vdevs == ZTEST_VDEV_CLASS_RND &&
+           ztest_random(2) == 0)) {
+               return;
+       }
+
+       mutex_enter(&ztest_vdev_lock);
+
+       /* Only test with mirrors */
+       if (zs->zs_mirrors < 2) {
+               mutex_exit(&ztest_vdev_lock);
+               return;
+       }
+
+       /* requires feature@allocation_classes */
+       if (!spa_feature_is_enabled(spa, SPA_FEATURE_ALLOCATION_CLASSES)) {
+               mutex_exit(&ztest_vdev_lock);
+               return;
+       }
+
+       leaves = MAX(zs->zs_mirrors + zs->zs_splits, 1) * ztest_opts.zo_raidz;
+
+       spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
+       ztest_shared->zs_vdev_next_leaf = find_vdev_hole(spa) * leaves;
+       spa_config_exit(spa, SCL_VDEV, FTAG);
+
+       nvroot = make_vdev_root(NULL, NULL, NULL, ztest_opts.zo_vdev_size, 0,
+           class, ztest_opts.zo_raidz, zs->zs_mirrors, 1);
+
+       error = spa_vdev_add(spa, nvroot);
+       nvlist_free(nvroot);
+
+       if (error == ENOSPC)
+               ztest_record_enospc("spa_vdev_add");
+       else if (error != 0)
+               fatal(0, "spa_vdev_add() = %d", error);
+
+       /*
+        * 50% of the time allow small blocks in the special class
+        */
+       if (error == 0 &&
+           spa_special_class(spa)->mc_groups == 1 && ztest_random(2) == 0) {
+               if (ztest_opts.zo_verbose >= 3)
+                       (void) printf("Enabling special VDEV small blocks\n");
+               (void) ztest_dsl_prop_set_uint64(zd->zd_name,
+                   ZFS_PROP_SPECIAL_SMALL_BLOCKS, 32768, B_FALSE);
        }
 
        mutex_exit(&ztest_vdev_lock);
+
+       if (ztest_opts.zo_verbose >= 3) {
+               metaslab_class_t *mc;
+
+               if (strcmp(class, VDEV_ALLOC_BIAS_SPECIAL) == 0)
+                       mc = spa_special_class(spa);
+               else
+                       mc = spa_dedup_class(spa);
+               (void) printf("Added a %s mirrored vdev (of %d)\n",
+                   class, (int)mc->mc_groups);
+       }
 }
 
 /*
@@ -3039,10 +3195,15 @@ ztest_vdev_aux_add_remove(ztest_ds_t *zd, uint64_t id)
                 * Add a new device.
                 */
                nvlist_t *nvroot = make_vdev_root(NULL, aux, NULL,
-                   (ztest_opts.zo_vdev_size * 5) / 4, 0, 0, 0, 0, 1);
+                   (ztest_opts.zo_vdev_size * 5) / 4, 0, NULL, 0, 0, 1);
                error = spa_vdev_add(spa, nvroot);
-               if (error != 0)
+
+               switch (error) {
+               case 0:
+                       break;
+               default:
                        fatal(0, "spa_vdev_add(%p) = %d", nvroot, error);
+               }
                nvlist_free(nvroot);
        } else {
                /*
@@ -3054,8 +3215,16 @@ ztest_vdev_aux_add_remove(ztest_ds_t *zd, uint64_t id)
                        (void) vdev_online(spa, guid, 0, NULL);
 
                error = spa_vdev_remove(spa, guid, B_FALSE);
-               if (error != 0 && error != EBUSY)
+
+               switch (error) {
+               case 0:
+               case EBUSY:
+               case ZFS_ERR_CHECKPOINT_EXISTS:
+               case ZFS_ERR_DISCARDING_CHECKPOINT:
+                       break;
+               default:
                        fatal(0, "spa_vdev_remove(%llu) = %d", guid, error);
+               }
        }
 
        mutex_exit(&ztest_vdev_lock);
@@ -3143,9 +3312,9 @@ ztest_split_pool(ztest_ds_t *zd, uint64_t id)
 
        spa_config_exit(spa, SCL_VDEV, FTAG);
 
-       (void) rw_wrlock(&ztest_name_lock);
+       (void) pthread_rwlock_wrlock(&ztest_name_lock);
        error = spa_vdev_split_mirror(spa, "splitp", config, NULL, B_FALSE);
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 
        nvlist_free(config);
 
@@ -3159,7 +3328,6 @@ ztest_split_pool(ztest_ds_t *zd, uint64_t id)
                --zs->zs_mirrors;
        }
        mutex_exit(&ztest_vdev_lock);
-
 }
 
 /*
@@ -3229,11 +3397,15 @@ ztest_vdev_attach_detach(ztest_ds_t *zd, uint64_t id)
         * Locate this vdev.
         */
        oldvd = rvd->vdev_child[top];
+
+       /* pick a child from the mirror */
        if (zs->zs_mirrors >= 1) {
                ASSERT(oldvd->vdev_ops == &vdev_mirror_ops);
                ASSERT(oldvd->vdev_children >= zs->zs_mirrors);
                oldvd = oldvd->vdev_child[leaf / ztest_opts.zo_raidz];
        }
+
+       /* pick a child out of the raidz group */
        if (ztest_opts.zo_raidz > 1) {
                ASSERT(oldvd->vdev_ops == &vdev_raidz_ops);
                ASSERT(oldvd->vdev_children == ztest_opts.zo_raidz);
@@ -3264,7 +3436,8 @@ ztest_vdev_attach_detach(ztest_ds_t *zd, uint64_t id)
                spa_config_exit(spa, SCL_ALL, FTAG);
                error = spa_vdev_detach(spa, oldguid, pguid, B_FALSE);
                if (error != 0 && error != ENODEV && error != EBUSY &&
-                   error != ENOTSUP)
+                   error != ENOTSUP && error != ZFS_ERR_CHECKPOINT_EXISTS &&
+                   error != ZFS_ERR_DISCARDING_CHECKPOINT)
                        fatal(0, "detach (%s) returned %d", oldpath, error);
                goto out;
        }
@@ -3334,7 +3507,7 @@ ztest_vdev_attach_detach(ztest_ds_t *zd, uint64_t id)
         * Build the nvlist describing newpath.
         */
        root = make_vdev_root(newpath, NULL, NULL, newvd == NULL ? newsize : 0,
-           ashift, 0, 0, 0, 1);
+           ashift, NULL, 0, 0, 1);
 
        error = spa_vdev_attach(spa, oldguid, root, replacing);
 
@@ -3355,6 +3528,10 @@ ztest_vdev_attach_detach(ztest_ds_t *zd, uint64_t id)
        if (error == EOVERFLOW || error == EBUSY)
                expected_error = error;
 
+       if (error == ZFS_ERR_CHECKPOINT_EXISTS ||
+           error == ZFS_ERR_DISCARDING_CHECKPOINT)
+               expected_error = error;
+
        /* XXX workaround 6690467 */
        if (error != expected_error && expected_error != EBUSY) {
                fatal(0, "attach (%s %llu, %s %llu, %d) "
@@ -3398,7 +3575,16 @@ ztest_device_removal(ztest_ds_t *zd, uint64_t id)
                ztest_device_removal_active = B_TRUE;
                mutex_exit(&ztest_vdev_lock);
 
-               while (spa->spa_vdev_removal != NULL)
+               /*
+                * spa->spa_vdev_removal is created in a sync task that
+                * is initiated via dsl_sync_task_nowait(). Since the
+                * task may not run before spa_vdev_remove() returns, we
+                * must wait at least 1 txg to ensure that the removal
+                * struct has been created.
+                */
+               txg_wait_synced(spa_get_dsl(spa), 0);
+
+               while (spa->spa_removing_phys.sr_state == DSS_SCANNING)
                        txg_wait_synced(spa_get_dsl(spa), 0);
        } else {
                mutex_exit(&ztest_vdev_lock);
@@ -3549,6 +3735,7 @@ ztest_vdev_LUN_growth(ztest_ds_t *zd, uint64_t id)
        uint64_t top;
        uint64_t old_class_space, new_class_space, old_ms_count, new_ms_count;
 
+       mutex_enter(&ztest_checkpoint_lock);
        mutex_enter(&ztest_vdev_lock);
        spa_config_enter(spa, SCL_STATE, spa, RW_READER);
 
@@ -3559,8 +3746,9 @@ ztest_vdev_LUN_growth(ztest_ds_t *zd, uint64_t id)
         * when the device removal completes).
         */
        if (ztest_device_removal_active) {
-               spa_config_exit(spa, SCL_STATE, FTAG);
+               spa_config_exit(spa, SCL_STATE, spa);
                mutex_exit(&ztest_vdev_lock);
+               mutex_exit(&ztest_checkpoint_lock);
                return;
        }
 
@@ -3590,10 +3778,11 @@ ztest_vdev_LUN_growth(ztest_ds_t *zd, uint64_t id)
            psize == 0 || psize >= 4 * ztest_opts.zo_vdev_size) {
                spa_config_exit(spa, SCL_STATE, spa);
                mutex_exit(&ztest_vdev_lock);
+               mutex_exit(&ztest_checkpoint_lock);
                return;
        }
        ASSERT(psize > 0);
-       newsize = psize + psize / 8;
+       newsize = psize + MAX(psize / 8, SPA_MAXBLOCKSIZE);
        ASSERT3U(newsize, >, psize);
 
        if (ztest_opts.zo_verbose >= 6) {
@@ -3615,6 +3804,7 @@ ztest_vdev_LUN_growth(ztest_ds_t *zd, uint64_t id)
                }
                spa_config_exit(spa, SCL_STATE, spa);
                mutex_exit(&ztest_vdev_lock);
+               mutex_exit(&ztest_checkpoint_lock);
                return;
        }
 
@@ -3649,6 +3839,7 @@ ztest_vdev_LUN_growth(ztest_ds_t *zd, uint64_t id)
                }
                spa_config_exit(spa, SCL_STATE, spa);
                mutex_exit(&ztest_vdev_lock);
+               mutex_exit(&ztest_checkpoint_lock);
                return;
        }
 
@@ -3679,6 +3870,7 @@ ztest_vdev_LUN_growth(ztest_ds_t *zd, uint64_t id)
 
        spa_config_exit(spa, SCL_STATE, spa);
        mutex_exit(&ztest_vdev_lock);
+       mutex_exit(&ztest_checkpoint_lock);
 }
 
 /*
@@ -3739,6 +3931,13 @@ ztest_dataset_create(char *dsname)
                VERIFY0(dsl_crypto_params_create_nvlist(DCP_CMD_NONE, props,
                    crypto_args, &dcp));
 
+               /*
+                * Cycle through all available encryption implementations
+                * to verify interoperability.
+                */
+               VERIFY0(gcm_impl_set("cycle"));
+               VERIFY0(aes_impl_set("cycle"));
+
                fnvlist_free(crypto_args);
                fnvlist_free(props);
        }
@@ -3786,9 +3985,13 @@ ztest_objset_destroy_cb(const char *name, void *arg)
                VERIFY0(dsl_destroy_snapshot(name, B_TRUE));
        } else {
                error = dsl_destroy_head(name);
-               /* There could be a hold on this dataset */
-               if (error != EBUSY)
+               if (error == ENOSPC) {
+                       /* There could be checkpoint or insufficient slop */
+                       ztest_record_enospc(FTAG);
+               } else if (error != EBUSY) {
+                       /* There could be a hold on this dataset */
                        ASSERT0(error);
+               }
        }
        return (0);
 }
@@ -3842,7 +4045,7 @@ ztest_dmu_objset_create_destroy(ztest_ds_t *zd, uint64_t id)
 
        zdtmp = umem_alloc(sizeof (ztest_ds_t), UMEM_NOFAIL);
 
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
 
        (void) snprintf(name, sizeof (name), "%s/temp_%llu",
            ztest_opts.zo_pool, (u_longlong_t)id);
@@ -3858,7 +4061,6 @@ ztest_dmu_objset_create_destroy(ztest_ds_t *zd, uint64_t id)
                ztest_zd_init(zdtmp, NULL, os);
                zil_replay(os, zdtmp, ztest_replay_vector);
                ztest_zd_fini(zdtmp);
-               txg_wait_synced(dmu_objset_pool(os), 0);
                dmu_objset_disown(os, B_TRUE, FTAG);
        }
 
@@ -3928,11 +4130,10 @@ ztest_dmu_objset_create_destroy(ztest_ds_t *zd, uint64_t id)
            B_FALSE, B_TRUE, FTAG, &os2));
 
        zil_close(zilog);
-       txg_wait_synced(spa_get_dsl(os->os_spa), 0);
        dmu_objset_disown(os, B_TRUE, FTAG);
        ztest_zd_fini(zdtmp);
 out:
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 
        umem_free(zdtmp, sizeof (ztest_ds_t));
 }
@@ -3943,10 +4144,10 @@ out:
 void
 ztest_dmu_snapshot_create_destroy(ztest_ds_t *zd, uint64_t id)
 {
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
        (void) ztest_snapshot_destroy(zd->zd_name, id);
        (void) ztest_snapshot_create(zd->zd_name, id);
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 }
 
 /*
@@ -4023,7 +4224,7 @@ ztest_dsl_dataset_promote_busy(ztest_ds_t *zd, uint64_t id)
        clone2name = umem_alloc(ZFS_MAX_DATASET_NAME_LEN, UMEM_NOFAIL);
        snap3name  = umem_alloc(ZFS_MAX_DATASET_NAME_LEN, UMEM_NOFAIL);
 
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
 
        ztest_dsl_dataset_cleanup(osname, id);
 
@@ -4101,7 +4302,7 @@ ztest_dsl_dataset_promote_busy(ztest_ds_t *zd, uint64_t id)
 out:
        ztest_dsl_dataset_cleanup(osname, id);
 
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 
        umem_free(snap1name, ZFS_MAX_DATASET_NAME_LEN);
        umem_free(clone1name, ZFS_MAX_DATASET_NAME_LEN);
@@ -5337,7 +5538,7 @@ ztest_dsl_prop_get_set(ztest_ds_t *zd, uint64_t id)
        };
        int p;
 
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
 
        for (p = 0; p < sizeof (proplist) / sizeof (proplist[0]); p++)
                (void) ztest_dsl_prop_set_uint64(zd->zd_name, proplist[p],
@@ -5346,21 +5547,21 @@ ztest_dsl_prop_get_set(ztest_ds_t *zd, uint64_t id)
        VERIFY0(ztest_dsl_prop_set_uint64(zd->zd_name, ZFS_PROP_RECORDSIZE,
            ztest_random_blocksize(), (int)ztest_random(2)));
 
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 }
 
 /* ARGSUSED */
 void
 ztest_remap_blocks(ztest_ds_t *zd, uint64_t id)
 {
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
 
        int error = dmu_objset_remap_indirects(zd->zd_name);
        if (error == ENOSPC)
                error = 0;
        ASSERT0(error);
 
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 }
 
 /* ARGSUSED */
@@ -5369,7 +5570,7 @@ ztest_spa_prop_get_set(ztest_ds_t *zd, uint64_t id)
 {
        nvlist_t *props = NULL;
 
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
 
        (void) ztest_spa_prop_set_uint64(ZPOOL_PROP_DEDUPDITTO,
            ZIO_DEDUPDITTO_MIN + ztest_random(ZIO_DEDUPDITTO_MIN));
@@ -5381,7 +5582,7 @@ ztest_spa_prop_get_set(ztest_ds_t *zd, uint64_t id)
 
        nvlist_free(props);
 
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 }
 
 static int
@@ -5416,7 +5617,7 @@ ztest_dmu_snapshot_hold(ztest_ds_t *zd, uint64_t id)
        char osname[ZFS_MAX_DATASET_NAME_LEN];
        nvlist_t *holds;
 
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
 
        dmu_objset_name(os, osname);
 
@@ -5522,7 +5723,7 @@ ztest_dmu_snapshot_hold(ztest_ds_t *zd, uint64_t id)
        VERIFY3U(dmu_objset_hold(fullname, FTAG, &origin), ==, ENOENT);
 
 out:
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 }
 
 /*
@@ -5579,7 +5780,7 @@ ztest_fault_inject(ztest_ds_t *zd, uint64_t id)
         * they are in progress (i.e. spa_change_guid). Those
         * operations will have grabbed the name lock as writer.
         */
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
 
        /*
         * We need SCL_STATE here because we're going to look at vd0->vdev_tsd.
@@ -5651,7 +5852,7 @@ ztest_fault_inject(ztest_ds_t *zd, uint64_t id)
 
                if (sav->sav_count == 0) {
                        spa_config_exit(spa, SCL_STATE, FTAG);
-                       (void) rw_unlock(&ztest_name_lock);
+                       (void) pthread_rwlock_unlock(&ztest_name_lock);
                        goto out;
                }
                vd0 = sav->sav_vdevs[ztest_random(sav->sav_count)];
@@ -5665,7 +5866,7 @@ ztest_fault_inject(ztest_ds_t *zd, uint64_t id)
        }
 
        spa_config_exit(spa, SCL_STATE, FTAG);
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 
        /*
         * If we can tolerate two or more faults, or we're dealing
@@ -5685,12 +5886,12 @@ ztest_fault_inject(ztest_ds_t *zd, uint64_t id)
                         * leaving the dataset in an inconsistent state.
                         */
                        if (islog)
-                               (void) rw_wrlock(&ztest_name_lock);
+                               (void) pthread_rwlock_wrlock(&ztest_name_lock);
 
                        VERIFY(vdev_offline(spa, guid0, flags) != EBUSY);
 
                        if (islog)
-                               (void) rw_unlock(&ztest_name_lock);
+                               (void) pthread_rwlock_unlock(&ztest_name_lock);
                } else {
                        /*
                         * Ideally we would like to be able to randomly
@@ -5715,7 +5916,7 @@ ztest_fault_inject(ztest_ds_t *zd, uint64_t id)
         */
        fd = open(pathrand, O_RDWR);
 
-       if (fd == -1)   /* we hit a gap in the device namespace */
+       if (fd == -1) /* we hit a gap in the device namespace */
                goto out;
 
        fsize = lseek(fd, 0, SEEK_END);
@@ -5833,13 +6034,13 @@ ztest_ddt_repair(ztest_ds_t *zd, uint64_t id)
         * Take the name lock as writer to prevent anyone else from changing
         * the pool and dataset properies we need to maintain during this test.
         */
-       (void) rw_wrlock(&ztest_name_lock);
+       (void) pthread_rwlock_wrlock(&ztest_name_lock);
 
        if (ztest_dsl_prop_set_uint64(zd->zd_name, ZFS_PROP_DEDUP, checksum,
            B_FALSE) != 0 ||
            ztest_dsl_prop_set_uint64(zd->zd_name, ZFS_PROP_COPIES, 1,
            B_FALSE) != 0) {
-               (void) rw_unlock(&ztest_name_lock);
+               (void) pthread_rwlock_unlock(&ztest_name_lock);
                umem_free(od, sizeof (ztest_od_t));
                return;
        }
@@ -5859,7 +6060,7 @@ ztest_ddt_repair(ztest_ds_t *zd, uint64_t id)
        dmu_tx_hold_write(tx, object, 0, copies * blocksize);
        txg = ztest_tx_assign(tx, TXG_WAIT, FTAG);
        if (txg == 0) {
-               (void) rw_unlock(&ztest_name_lock);
+               (void) pthread_rwlock_unlock(&ztest_name_lock);
                umem_free(od, sizeof (ztest_od_t));
                return;
        }
@@ -5908,7 +6109,7 @@ ztest_ddt_repair(ztest_ds_t *zd, uint64_t id)
 
        abd_free(abd);
 
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
        umem_free(od, sizeof (ztest_od_t));
 }
 
@@ -5949,9 +6150,9 @@ ztest_reguid(ztest_ds_t *zd, uint64_t id)
        orig = spa_guid(spa);
        load = spa_load_guid(spa);
 
-       (void) rw_wrlock(&ztest_name_lock);
+       (void) pthread_rwlock_wrlock(&ztest_name_lock);
        error = spa_change_guid(spa);
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 
        if (error != 0)
                return;
@@ -5965,62 +6166,6 @@ ztest_reguid(ztest_ds_t *zd, uint64_t id)
        VERIFY3U(load, ==, spa_load_guid(spa));
 }
 
-/*
- * Rename the pool to a different name and then rename it back.
- */
-/* ARGSUSED */
-void
-ztest_spa_rename(ztest_ds_t *zd, uint64_t id)
-{
-       char *oldname, *newname;
-       spa_t *spa;
-
-       if (ztest_opts.zo_mmp_test)
-               return;
-
-       (void) rw_wrlock(&ztest_name_lock);
-
-       oldname = ztest_opts.zo_pool;
-       newname = umem_alloc(strlen(oldname) + 5, UMEM_NOFAIL);
-       (void) strcpy(newname, oldname);
-       (void) strcat(newname, "_tmp");
-
-       /*
-        * Do the rename
-        */
-       VERIFY3U(0, ==, spa_rename(oldname, newname));
-
-       /*
-        * Try to open it under the old name, which shouldn't exist
-        */
-       VERIFY3U(ENOENT, ==, spa_open(oldname, &spa, FTAG));
-
-       /*
-        * Open it under the new name and make sure it's still the same spa_t.
-        */
-       VERIFY3U(0, ==, spa_open(newname, &spa, FTAG));
-
-       ASSERT(spa == ztest_spa);
-       spa_close(spa, FTAG);
-
-       /*
-        * Rename it back to the original
-        */
-       VERIFY3U(0, ==, spa_rename(newname, oldname));
-
-       /*
-        * Make sure it can still be opened
-        */
-       VERIFY3U(0, ==, spa_open(oldname, &spa, FTAG));
-
-       ASSERT(spa == ztest_spa);
-       spa_close(spa, FTAG);
-
-       umem_free(newname, strlen(newname) + 1);
-
-       (void) rw_unlock(&ztest_name_lock);
-}
-
 void
 ztest_fletcher(ztest_ds_t *zd, uint64_t id)
 {
@@ -6201,6 +6346,97 @@ ztest_get_zdb_bin(char *bin, int len)
        strcpy(bin, "zdb");
 }
 
+static vdev_t *
+ztest_random_concrete_vdev_leaf(vdev_t *vd)
+{
+       if (vd == NULL)
+               return (NULL);
+
+       if (vd->vdev_children == 0)
+               return (vd);
+
+       vdev_t *eligible[vd->vdev_children];
+       int eligible_idx = 0, i;
+       for (i = 0; i < vd->vdev_children; i++) {
+               vdev_t *cvd = vd->vdev_child[i];
+               if (cvd->vdev_top->vdev_removing)
+                       continue;
+               if (cvd->vdev_children > 0 ||
+                   (vdev_is_concrete(cvd) && !cvd->vdev_detached)) {
+                       eligible[eligible_idx++] = cvd;
+               }
+       }
+       VERIFY(eligible_idx > 0);
+
+       uint64_t child_no = ztest_random(eligible_idx);
+       return (ztest_random_concrete_vdev_leaf(eligible[child_no]));
+}
+
+/* ARGSUSED */
+void
+ztest_initialize(ztest_ds_t *zd, uint64_t id)
+{
+       spa_t *spa = ztest_spa;
+       int error = 0;
+
+       mutex_enter(&ztest_vdev_lock);
+
+       spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
+
+       /* Random leaf vdev */
+       vdev_t *rand_vd = ztest_random_concrete_vdev_leaf(spa->spa_root_vdev);
+       if (rand_vd == NULL) {
+               spa_config_exit(spa, SCL_VDEV, FTAG);
+               mutex_exit(&ztest_vdev_lock);
+               return;
+       }
+
+       /*
+        * The random vdev we've selected may change as soon as we
+        * drop the spa_config_lock. We create local copies of things
+        * we're interested in.
+        */
+       uint64_t guid = rand_vd->vdev_guid;
+       char *path = strdup(rand_vd->vdev_path);
+       boolean_t active = rand_vd->vdev_initialize_thread != NULL;
+
+       zfs_dbgmsg("vd %p, guid %llu", rand_vd, guid);
+       spa_config_exit(spa, SCL_VDEV, FTAG);
+
+       uint64_t cmd = ztest_random(POOL_INITIALIZE_FUNCS);
+       error = spa_vdev_initialize(spa, guid, cmd);
+       switch (cmd) {
+       case POOL_INITIALIZE_CANCEL:
+               if (ztest_opts.zo_verbose >= 4) {
+                       (void) printf("Cancel initialize %s", path);
+                       if (!active)
+                               (void) printf(" failed (no initialize active)");
+                       (void) printf("\n");
+               }
+               break;
+       case POOL_INITIALIZE_DO:
+               if (ztest_opts.zo_verbose >= 4) {
+                       (void) printf("Start initialize %s", path);
+                       if (active && error == 0)
+                               (void) printf(" failed (already active)");
+                       else if (error != 0)
+                               (void) printf(" failed (error %d)", error);
+                       (void) printf("\n");
+               }
+               break;
+       case POOL_INITIALIZE_SUSPEND:
+               if (ztest_opts.zo_verbose >= 4) {
+                       (void) printf("Suspend initialize %s", path);
+                       if (!active)
+                               (void) printf(" failed (no initialize active)");
+                       (void) printf("\n");
+               }
+               break;
+       }
+       free(path);
+       mutex_exit(&ztest_vdev_lock);
+}
+
 /*
  * Verify pool integrity by running zdb.
  */
@@ -6222,7 +6458,7 @@ ztest_run_zdb(char *pool)
 
        (void) sprintf(zdb,
            "%s -bcc%s%s -G -d -U %s "
-           "-o zfs_reconstruct_indirect_combinations_max=1000000 %s",
+           "-o zfs_reconstruct_indirect_combinations_max=65536 %s",
            bin,
            ztest_opts.zo_verbose >= 3 ? "s" : "",
            ztest_opts.zo_verbose >= 4 ? "v" : "",
@@ -6386,6 +6622,12 @@ ztest_resume_thread(void *arg)
                 */
                if (ztest_random(10) == 0)
                        zfs_abd_scatter_enabled = ztest_random(2);
+
+               /*
+                * Periodically inject remapping delays (10% of the time).
+                */
+               zfs_object_remap_one_indirect_delay_ms =
+                   ztest_random(10) == 0 ? ztest_random(1000) + 1 : 0;
        }
 
        thread_exit();
@@ -6396,13 +6638,20 @@ ztest_deadman_thread(void *arg)
 {
        ztest_shared_t *zs = arg;
        spa_t *spa = ztest_spa;
-       hrtime_t delta, overdue, total = 0;
+       hrtime_t delay, overdue, last_run = gethrtime();
 
-       for (;;) {
-               delta = zs->zs_thread_stop - zs->zs_thread_start +
-                   MSEC2NSEC(zfs_deadman_synctime_ms);
+       delay = (zs->zs_thread_stop - zs->zs_thread_start) +
+           MSEC2NSEC(zfs_deadman_synctime_ms);
 
-               (void) poll(NULL, 0, (int)NSEC2MSEC(delta));
+       while (!ztest_exiting) {
+               /*
+                * Wait for the delay timer while checking occasionally
+                * if we should stop.
+                */
+               if (gethrtime() < last_run + delay) {
+                       (void) poll(NULL, 0, 1000);
+                       continue;
+               }
 
                /*
                 * If the pool is suspended then fail immediately. Otherwise,
@@ -6423,15 +6672,20 @@ ztest_deadman_thread(void *arg)
                 * then it may be hung and is terminated.
                 */
                overdue = zs->zs_proc_stop + MSEC2NSEC(zfs_deadman_synctime_ms);
-               total += zfs_deadman_synctime_ms / 1000;
                if (gethrtime() > overdue) {
                        fatal(0, "aborting test after %llu seconds because "
-                           "the process is overdue for termination.", total);
+                           "the process is overdue for termination.",
+                           (gethrtime() - zs->zs_proc_start) / NANOSEC);
                }
 
                (void) printf("ztest has been running for %lld seconds\n",
-                   total);
+                   (gethrtime() - zs->zs_proc_start) / NANOSEC);
+
+               last_run = gethrtime();
+               delay = MSEC2NSEC(zfs_deadman_checktime_ms);
        }
+
+       thread_exit();
 }
 
 static void
@@ -6560,11 +6814,11 @@ ztest_dataset_open(int d)
 
        ztest_dataset_name(name, ztest_opts.zo_pool, d);
 
-       (void) rw_rdlock(&ztest_name_lock);
+       (void) pthread_rwlock_rdlock(&ztest_name_lock);
 
        error = ztest_dataset_create(name);
        if (error == ENOSPC) {
-               (void) rw_unlock(&ztest_name_lock);
+               (void) pthread_rwlock_unlock(&ztest_name_lock);
                ztest_record_enospc(FTAG);
                return (error);
        }
@@ -6572,7 +6826,7 @@ ztest_dataset_open(int d)
 
        VERIFY0(ztest_dmu_objset_own(name, DMU_OST_OTHER, B_FALSE,
            B_TRUE, zd, &os));
-       (void) rw_unlock(&ztest_name_lock);
+       (void) pthread_rwlock_unlock(&ztest_name_lock);
 
        ztest_zd_init(zd, ZTEST_GET_SHARED_DS(d), os);
 
@@ -6612,12 +6866,44 @@ ztest_dataset_close(int d)
        ztest_ds_t *zd = &ztest_ds[d];
 
        zil_close(zd->zd_zilog);
-       txg_wait_synced(spa_get_dsl(zd->zd_os->os_spa), 0);
        dmu_objset_disown(zd->zd_os, B_TRUE, zd);
 
        ztest_zd_fini(zd);
 }
 
+/* ARGSUSED */
+static int
+ztest_replay_zil_cb(const char *name, void *arg)
+{
+       objset_t *os;
+       ztest_ds_t *zdtmp;
+
+       VERIFY0(ztest_dmu_objset_own(name, DMU_OST_ANY, B_TRUE,
+           B_TRUE, FTAG, &os));
+
+       zdtmp = umem_alloc(sizeof (ztest_ds_t), UMEM_NOFAIL);
+
+       ztest_zd_init(zdtmp, NULL, os);
+       zil_replay(os, zdtmp, ztest_replay_vector);
+       ztest_zd_fini(zdtmp);
+
+       if (dmu_objset_zil(os)->zl_parse_lr_count != 0 &&
+           ztest_opts.zo_verbose >= 6) {
+               zilog_t *zilog = dmu_objset_zil(os);
+
+               (void) printf("%s replay %llu blocks, %llu records, seq %llu\n",
+                   name,
+                   (u_longlong_t)zilog->zl_parse_blk_count,
+                   (u_longlong_t)zilog->zl_parse_lr_count,
+                   (u_longlong_t)zilog->zl_replaying_seq);
+       }
+
+       umem_free(zdtmp, sizeof (ztest_ds_t));
+
+       dmu_objset_disown(os, B_TRUE, FTAG);
+       return (0);
+}
+
 /*
  * Kick off threads to run tests on all datasets in parallel.
  */
@@ -6626,7 +6912,7 @@ ztest_run(ztest_shared_t *zs)
 {
        spa_t *spa;
        objset_t *os;
-       kthread_t *resume_thread;
+       kthread_t *resume_thread, *deadman_thread;
        kthread_t **run_threads;
        uint64_t object;
        int error;
@@ -6638,7 +6924,8 @@ ztest_run(ztest_shared_t *zs)
         * Initialize parent/child shared state.
         */
        mutex_init(&ztest_vdev_lock, NULL, MUTEX_DEFAULT, NULL);
-       VERIFY(rwlock_init(&ztest_name_lock, USYNC_THREAD, NULL) == 0);
+       mutex_init(&ztest_checkpoint_lock, NULL, MUTEX_DEFAULT, NULL);
+       VERIFY0(pthread_rwlock_init(&ztest_name_lock, NULL));
 
        zs->zs_thread_start = gethrtime();
        zs->zs_thread_stop =
@@ -6683,13 +6970,13 @@ ztest_run(ztest_shared_t *zs)
        /*
         * Create a deadman thread and set to panic if we hang.
         */
-       (void) thread_create(NULL, 0, ztest_deadman_thread,
+       deadman_thread = thread_create(NULL, 0, ztest_deadman_thread,
            zs, 0, NULL, TS_RUN | TS_JOINABLE, defclsyspri);
 
        spa->spa_deadman_failmode = ZIO_FAILURE_MODE_PANIC;
 
        /*
-        * Verify that we can safely inquire about about any object,
+        * Verify that we can safely inquire about any object,
         * whether it's allocated or not.  To make it interesting,
         * we probe a 5-wide window around each power of two.
         * This hits all edge cases, including zero and the max.
@@ -6712,12 +6999,41 @@ ztest_run(ztest_shared_t *zs)
        }
        zs->zs_enospc_count = 0;
 
+       /*
+        * If we were in the middle of ztest_device_removal() and were killed
+        * we need to ensure the removal and scrub complete before running
+        * any tests that check ztest_device_removal_active. The removal will
+        * be restarted automatically when the spa is opened, but we need to
+        * initate the scrub manually if it is not already in progress. Note
+        * that we always run the scrub whenever an indirect vdev exists
+        * because we have no way of knowing for sure if ztest_device_removal()
+        * fully completed its scrub before the pool was reimported.
+        */
+       if (spa->spa_removing_phys.sr_state == DSS_SCANNING ||
+           spa->spa_removing_phys.sr_prev_indirect_vdev != -1) {
+               while (spa->spa_removing_phys.sr_state == DSS_SCANNING)
+                       txg_wait_synced(spa_get_dsl(spa), 0);
+
+               (void) spa_scan(spa, POOL_SCAN_SCRUB);
+               while (dsl_scan_scrubbing(spa_get_dsl(spa)))
+                       txg_wait_synced(spa_get_dsl(spa), 0);
+       }
+
        run_threads = umem_zalloc(ztest_opts.zo_threads * sizeof (kthread_t *),
            UMEM_NOFAIL);
 
        if (ztest_opts.zo_verbose >= 4)
                (void) printf("starting main threads...\n");
 
+       /*
+        * Replay all logs of all datasets in the pool. This is primarily for
+        * temporary datasets which wouldn't otherwise get replayed, which
+        * can trigger failures when attempting to offline a SLOG in
+        * ztest_fault_inject().
+        */
+       (void) dmu_objset_find(ztest_opts.zo_pool, ztest_replay_zil_cb,
+           NULL, DS_FIND_CHILDREN);
+
        /*
         * Kick off all the tests that run in parallel.
         */
@@ -6734,11 +7050,17 @@ ztest_run(ztest_shared_t *zs)
        }
 
        /*
-        * Wait for all of the tests to complete.  We go in reverse order
-        * so we don't close datasets while threads are still using them.
+        * Wait for all of the tests to complete.
         */
-       for (t = ztest_opts.zo_threads - 1; t >= 0; t--) {
+       for (t = 0; t < ztest_opts.zo_threads; t++)
                VERIFY0(thread_join(run_threads[t]));
+
+       /*
+        * Close all datasets. This must be done after all the threads
+        * are joined so we can be sure none of the datasets are in-use
+        * by any of the threads.
+        */
+       for (t = 0; t < ztest_opts.zo_threads; t++) {
                if (t < ztest_opts.zo_datasets)
                        ztest_dataset_close(t);
        }
@@ -6750,9 +7072,10 @@ ztest_run(ztest_shared_t *zs)
 
        umem_free(run_threads, ztest_opts.zo_threads * sizeof (kthread_t *));
 
-       /* Kill the resume thread */
+       /* Kill the resume and deadman threads */
        ztest_exiting = B_TRUE;
        VERIFY0(thread_join(resume_thread));
+       VERIFY0(thread_join(deadman_thread));
        ztest_resume(spa);
 
        /*
@@ -6795,8 +7118,9 @@ ztest_run(ztest_shared_t *zs)
 
        list_destroy(&zcl.zcl_callbacks);
        mutex_destroy(&zcl.zcl_callbacks_lock);
-       (void) rwlock_destroy(&ztest_name_lock);
+       (void) pthread_rwlock_destroy(&ztest_name_lock);
        mutex_destroy(&ztest_vdev_lock);
+       mutex_destroy(&ztest_checkpoint_lock);
 }
 
 static void
@@ -6920,6 +7244,7 @@ make_random_props(void)
        nvlist_t *props;
 
        VERIFY0(nvlist_alloc(&props, NV_UNIQUE_NAME, 0));
+
        if (ztest_random(2) == 0)
                return (props);
 
@@ -6935,7 +7260,6 @@ make_random_props(void)
 static void
 ztest_import(ztest_shared_t *zs)
 {
-       libzfs_handle_t *hdl;
        importargs_t args = { 0 };
        spa_t *spa;
        nvlist_t *cfg = NULL;
@@ -6946,17 +7270,18 @@ ztest_import(ztest_shared_t *zs)
        int error;
 
        mutex_init(&ztest_vdev_lock, NULL, MUTEX_DEFAULT, NULL);
-       VERIFY(rwlock_init(&ztest_name_lock, USYNC_THREAD, NULL) == 0);
+       mutex_init(&ztest_checkpoint_lock, NULL, MUTEX_DEFAULT, NULL);
+       VERIFY0(pthread_rwlock_init(&ztest_name_lock, NULL));
 
        kernel_init(FREAD | FWRITE);
-       hdl = libzfs_init();
 
        searchdirs[0] = ztest_opts.zo_dir;
        args.paths = nsearch;
        args.path = searchdirs;
        args.can_be_active = B_FALSE;
 
-       error = zpool_tryimport(hdl, name, &cfg, &args);
+       error = zpool_find_config(NULL, name, &cfg, &args,
+           &libzpool_config_ops);
        if (error)
                (void) fatal(0, "No pools found\n");
 
@@ -6966,7 +7291,6 @@ ztest_import(ztest_shared_t *zs)
            1ULL << spa->spa_root_vdev->vdev_child[0]->vdev_ms_shift;
        spa_close(spa, FTAG);
 
-       libzfs_fini(hdl);
        kernel_fini();
 
        if (!ztest_opts.zo_mmp_test) {
@@ -6975,8 +7299,9 @@ ztest_import(ztest_shared_t *zs)
                ztest_run_zdb(ztest_opts.zo_pool);
        }
 
-       (void) rwlock_destroy(&ztest_name_lock);
+       (void) pthread_rwlock_destroy(&ztest_name_lock);
        mutex_destroy(&ztest_vdev_lock);
+       mutex_destroy(&ztest_checkpoint_lock);
 }
 
 /*
@@ -6991,7 +7316,8 @@ ztest_init(ztest_shared_t *zs)
        int i;
 
        mutex_init(&ztest_vdev_lock, NULL, MUTEX_DEFAULT, NULL);
-       VERIFY(rwlock_init(&ztest_name_lock, USYNC_THREAD, NULL) == 0);
+       mutex_init(&ztest_checkpoint_lock, NULL, MUTEX_DEFAULT, NULL);
+       VERIFY0(pthread_rwlock_init(&ztest_name_lock, NULL));
 
        kernel_init(FREAD | FWRITE);
 
@@ -7003,7 +7329,7 @@ ztest_init(ztest_shared_t *zs)
        zs->zs_splits = 0;
        zs->zs_mirrors = ztest_opts.zo_mirrors;
        nvroot = make_vdev_root(NULL, NULL, NULL, ztest_opts.zo_vdev_size, 0,
-           0, ztest_opts.zo_raidz, zs->zs_mirrors, 1);
+           NULL, ztest_opts.zo_raidz, zs->zs_mirrors, 1);
        props = make_random_props();
 
        /*
@@ -7040,8 +7366,9 @@ ztest_init(ztest_shared_t *zs)
                ztest_run_zdb(ztest_opts.zo_pool);
        }
 
-       (void) rwlock_destroy(&ztest_name_lock);
+       (void) pthread_rwlock_destroy(&ztest_name_lock);
        mutex_destroy(&ztest_vdev_lock);
+       mutex_destroy(&ztest_checkpoint_lock);
 }
 
 static void
@@ -7236,7 +7563,6 @@ main(int argc, char **argv)
        ztest_shared_callstate_t *zc;
        char timebuf[100];
        char numbuf[NN_NUMBUF_SZ];
-       spa_t *spa;
        char *cmd;
        boolean_t hasalt;
        int f;
@@ -7247,6 +7573,25 @@ main(int argc, char **argv)
 
        dprintf_setup(&argc, argv);
        zfs_deadman_synctime_ms = 300000;
+       zfs_deadman_checktime_ms = 30000;
+       /*
+        * As two-word space map entries may not come up often (especially
+        * if pool and vdev sizes are small) we want to force at least some
+        * of them so the feature get tested.
+        */
+       zfs_force_some_double_word_sm_entries = B_TRUE;
+
+       /*
+        * Verify that even extensively damaged split blocks with many
+        * segments can be reconstructed in a reasonable amount of time
+        * when reconstruction is known to be possible.
+        *
+        * Note: the lower this value is, the more damage we inflict, and
+        * the more time ztest spends in recovering that damage. We chose
+        * to induce damage 1/100th of the time so recovery is tested but
+        * not so frequently that ztest doesn't get to test other code paths.
+        */
+       zfs_reconstruct_indirect_damage_fraction = 100;
 
        action.sa_handler = sig_handler;
        sigemptyset(&action.sa_mask);
@@ -7425,24 +7770,6 @@ main(int argc, char **argv)
                        (void) printf("\n");
                }
 
-               /*
-                * It's possible that we killed a child during a rename test,
-                * in which case we'll have a 'ztest_tmp' pool lying around
-                * instead of 'ztest'.  Do a blind rename in case this happened.
-                */
-               kernel_init(FREAD);
-               if (spa_open(ztest_opts.zo_pool, &spa, FTAG) == 0) {
-                       spa_close(spa, FTAG);
-               } else {
-                       char tmpname[ZFS_MAX_DATASET_NAME_LEN];
-                       kernel_fini();
-                       kernel_init(FREAD | FWRITE);
-                       (void) snprintf(tmpname, sizeof (tmpname), "%s_tmp",
-                           ztest_opts.zo_pool);
-                       (void) spa_rename(tmpname, ztest_opts.zo_pool);
-               }
-               kernel_fini();
-
                if (!ztest_opts.zo_mmp_test)
                        ztest_run_zdb(ztest_opts.zo_pool);
        }