]> granicus.if.org Git - zfs/blobdiff - module/zfs/spa_misc.c
OpenZFS 9166 - zfs storage pool checkpoint
[zfs] / module / zfs / spa_misc.c
index 8e23bcf450d20a42d636a1d3836da1b862fcae04..9410fab0763cdb32b43c5428c0a844561b0f5efc 100644 (file)
@@ -56,7 +56,7 @@
 #include <sys/kstat.h>
 #include "zfs_prop.h"
 #include <sys/zfeature.h>
-#include "qat_compress.h"
+#include "qat.h"
 
 /*
  * SPA locking
@@ -243,8 +243,12 @@ kmem_cache_t *spa_buffer_pool;
 int spa_mode_global;
 
 #ifdef ZFS_DEBUG
-/* Everything except dprintf and spa is on by default in debug builds */
-int zfs_flags = ~(ZFS_DEBUG_DPRINTF | ZFS_DEBUG_SPA);
+/*
+ * Everything except dprintf, set_error, spa, and indirect_remap is on
+ * by default in debug builds.
+ */
+int zfs_flags = ~(ZFS_DEBUG_DPRINTF | ZFS_DEBUG_SET_ERROR |
+    ZFS_DEBUG_INDIRECT_REMAP);
 #else
 int zfs_flags = 0;
 #endif
@@ -292,24 +296,41 @@ int zfs_free_leak_on_eio = B_FALSE;
 /*
  * Expiration time in milliseconds. This value has two meanings. First it is
  * used to determine when the spa_deadman() logic should fire. By default the
- * spa_deadman() will fire if spa_sync() has not completed in 1000 seconds.
+ * spa_deadman() will fire if spa_sync() has not completed in 600 seconds.
  * Secondly, the value determines if an I/O is considered "hung". Any I/O that
  * has not completed in zfs_deadman_synctime_ms is considered "hung" resulting
- * in a system panic.
+ * in one of three behaviors controlled by zfs_deadman_failmode.
+ */
+unsigned long zfs_deadman_synctime_ms = 600000ULL;
+
+/*
+ * This value controls the maximum amount of time zio_wait() will block for an
+ * outstanding IO.  By default this is 300 seconds at which point the "hung"
+ * behavior will be applied as described for zfs_deadman_synctime_ms.
  */
-unsigned long zfs_deadman_synctime_ms = 1000000ULL;
+unsigned long zfs_deadman_ziotime_ms = 300000ULL;
 
 /*
  * Check time in milliseconds. This defines the frequency at which we check
  * for hung I/O.
  */
-unsigned long  zfs_deadman_checktime_ms = 5000ULL;
+unsigned long  zfs_deadman_checktime_ms = 60000ULL;
 
 /*
  * By default the deadman is enabled.
  */
 int zfs_deadman_enabled = 1;
 
+/*
+ * Controls the behavior of the deadman when it detects a "hung" I/O.
+ * Valid values are zfs_deadman_failmode=<wait|continue|panic>.
+ *
+ * wait     - Wait for the "hung" I/O (default)
+ * continue - Attempt to recover from a "hung" I/O
+ * panic    - Panic the system
+ */
+char *zfs_deadman_failmode = "wait";
+
 /*
  * The worst case is single-sector max-parity RAID-Z blocks, in which
  * case the space requirement is exactly (VDEV_RAIDZ_MAXPARITY + 1)
@@ -336,12 +357,15 @@ int spa_asize_inflation = 24;
  * These are the operations that call dsl_pool_adjustedsize() with the netfree
  * argument set to TRUE.
  *
+ * Operations that are almost guaranteed to free up space in the absence of
+ * a pool checkpoint can use up to three quarters of the slop space
+ * (e.g zfs destroy).
+ *
  * A very restricted set of operations are always permitted, regardless of
  * the amount of free space.  These are the operations that call
- * dsl_sync_task(ZFS_SPACE_CHECK_NONE), e.g. "zfs destroy".  If these
- * operations result in a net increase in the amount of space used,
- * it is possible to run the pool completely out of space, causing it to
- * be permanently read-only.
+ * dsl_sync_task(ZFS_SPACE_CHECK_NONE). If these operations result in a net
+ * increase in the amount of space used, it is possible to run the pool
+ * completely out of space, causing it to be permanently read-only.
  *
  * Note that on very small pools, the slop space will be larger than
  * 3.2%, in an effort to have it be at least spa_min_slop (128MB),
@@ -352,6 +376,36 @@ int spa_asize_inflation = 24;
 int spa_slop_shift = 5;
 uint64_t spa_min_slop = 128 * 1024 * 1024;
 
+/*PRINTFLIKE2*/
+void
+spa_load_failed(spa_t *spa, const char *fmt, ...)
+{
+       va_list adx;
+       char buf[256];
+
+       va_start(adx, fmt);
+       (void) vsnprintf(buf, sizeof (buf), fmt, adx);
+       va_end(adx);
+
+       zfs_dbgmsg("spa_load(%s, config %s): FAILED: %s", spa->spa_name,
+           spa->spa_trust_config ? "trusted" : "untrusted", buf);
+}
+
+/*PRINTFLIKE2*/
+void
+spa_load_note(spa_t *spa, const char *fmt, ...)
+{
+       va_list adx;
+       char buf[256];
+
+       va_start(adx, fmt);
+       (void) vsnprintf(buf, sizeof (buf), fmt, adx);
+       va_end(adx);
+
+       zfs_dbgmsg("spa_load(%s, config %s): %s", spa->spa_name,
+           spa->spa_trust_config ? "trusted" : "untrusted", buf);
+}
+
 /*
  * ==========================================================================
  * SPA config locking
@@ -360,9 +414,7 @@ uint64_t spa_min_slop = 128 * 1024 * 1024;
 static void
 spa_config_lock_init(spa_t *spa)
 {
-       int i;
-
-       for (i = 0; i < SCL_LOCKS; i++) {
+       for (int i = 0; i < SCL_LOCKS; i++) {
                spa_config_lock_t *scl = &spa->spa_config_lock[i];
                mutex_init(&scl->scl_lock, NULL, MUTEX_DEFAULT, NULL);
                cv_init(&scl->scl_cv, NULL, CV_DEFAULT, NULL);
@@ -375,9 +427,7 @@ spa_config_lock_init(spa_t *spa)
 static void
 spa_config_lock_destroy(spa_t *spa)
 {
-       int i;
-
-       for (i = 0; i < SCL_LOCKS; i++) {
+       for (int i = 0; i < SCL_LOCKS; i++) {
                spa_config_lock_t *scl = &spa->spa_config_lock[i];
                mutex_destroy(&scl->scl_lock);
                cv_destroy(&scl->scl_cv);
@@ -390,9 +440,7 @@ spa_config_lock_destroy(spa_t *spa)
 int
 spa_config_tryenter(spa_t *spa, int locks, void *tag, krw_t rw)
 {
-       int i;
-
-       for (i = 0; i < SCL_LOCKS; i++) {
+       for (int i = 0; i < SCL_LOCKS; i++) {
                spa_config_lock_t *scl = &spa->spa_config_lock[i];
                if (!(locks & (1 << i)))
                        continue;
@@ -424,11 +472,10 @@ void
 spa_config_enter(spa_t *spa, int locks, void *tag, krw_t rw)
 {
        int wlocks_held = 0;
-       int i;
 
        ASSERT3U(SCL_LOCKS, <, sizeof (wlocks_held) * NBBY);
 
-       for (i = 0; i < SCL_LOCKS; i++) {
+       for (int i = 0; i < SCL_LOCKS; i++) {
                spa_config_lock_t *scl = &spa->spa_config_lock[i];
                if (scl->scl_writer == curthread)
                        wlocks_held |= (1 << i);
@@ -451,15 +498,13 @@ spa_config_enter(spa_t *spa, int locks, void *tag, krw_t rw)
                (void) refcount_add(&scl->scl_count, tag);
                mutex_exit(&scl->scl_lock);
        }
-       ASSERT(wlocks_held <= locks);
+       ASSERT3U(wlocks_held, <=, locks);
 }
 
 void
 spa_config_exit(spa_t *spa, int locks, void *tag)
 {
-       int i;
-
-       for (i = SCL_LOCKS - 1; i >= 0; i--) {
+       for (int i = SCL_LOCKS - 1; i >= 0; i--) {
                spa_config_lock_t *scl = &spa->spa_config_lock[i];
                if (!(locks & (1 << i)))
                        continue;
@@ -478,9 +523,9 @@ spa_config_exit(spa_t *spa, int locks, void *tag)
 int
 spa_config_held(spa_t *spa, int locks, krw_t rw)
 {
-       int i, locks_held = 0;
+       int locks_held = 0;
 
-       for (i = 0; i < SCL_LOCKS; i++) {
+       for (int i = 0; i < SCL_LOCKS; i++) {
                spa_config_lock_t *scl = &spa->spa_config_lock[i];
                if (!(locks & (1 << i)))
                        continue;
@@ -545,7 +590,7 @@ spa_deadman(void *arg)
            (gethrtime() - spa->spa_sync_starttime) / NANOSEC,
            ++spa->spa_deadman_calls);
        if (zfs_deadman_enabled)
-               vdev_deadman(spa->spa_root_vdev);
+               vdev_deadman(spa->spa_root_vdev, FTAG);
 
        spa->spa_deadman_tqid = taskq_dispatch_delay(system_delay_taskq,
            spa_deadman, spa, TQ_SLEEP, ddi_get_lbolt() +
@@ -562,8 +607,6 @@ spa_add(const char *name, nvlist_t *config, const char *altroot)
 {
        spa_t *spa;
        spa_config_dirent_t *dp;
-       int t;
-       int i;
 
        ASSERT(MUTEX_HELD(&spa_namespace_lock));
 
@@ -589,7 +632,7 @@ spa_add(const char *name, nvlist_t *config, const char *altroot)
        cv_init(&spa->spa_scrub_io_cv, NULL, CV_DEFAULT, NULL);
        cv_init(&spa->spa_suspend_cv, NULL, CV_DEFAULT, NULL);
 
-       for (t = 0; t < TXG_SIZE; t++)
+       for (int t = 0; t < TXG_SIZE; t++)
                bplist_create(&spa->spa_free_bplist[t]);
 
        (void) strlcpy(spa->spa_name, name, sizeof (spa->spa_name));
@@ -599,8 +642,11 @@ spa_add(const char *name, nvlist_t *config, const char *altroot)
        spa->spa_load_max_txg = UINT64_MAX;
        spa->spa_proc = &p0;
        spa->spa_proc_state = SPA_PROC_NONE;
+       spa->spa_trust_config = B_TRUE;
 
        spa->spa_deadman_synctime = MSEC2NSEC(zfs_deadman_synctime_ms);
+       spa->spa_deadman_ziotime = MSEC2NSEC(zfs_deadman_ziotime_ms);
+       spa_set_deadman_failmode(spa, zfs_deadman_failmode);
 
        refcount_create(&spa->spa_refcount);
        spa_config_lock_init(spa);
@@ -647,8 +693,6 @@ spa_add(const char *name, nvlist_t *config, const char *altroot)
                    KM_SLEEP) == 0);
        }
 
-       spa->spa_debug = ((zfs_flags & ZFS_DEBUG_SPA) != 0);
-
        spa->spa_min_ashift = INT_MAX;
        spa->spa_max_ashift = 0;
 
@@ -660,7 +704,7 @@ spa_add(const char *name, nvlist_t *config, const char *altroot)
         * setting SPA_FEATURE_DISABLED for all entries in the feature
         * refcount cache.
         */
-       for (i = 0; i < SPA_FEATURES; i++) {
+       for (int i = 0; i < SPA_FEATURES; i++) {
                spa->spa_feat_refcount_cache[i] = SPA_FEATURE_DISABLED;
        }
 
@@ -676,7 +720,6 @@ void
 spa_remove(spa_t *spa)
 {
        spa_config_dirent_t *dp;
-       int t;
 
        ASSERT(MUTEX_HELD(&spa_namespace_lock));
        ASSERT(spa->spa_state == POOL_STATE_UNINITIALIZED);
@@ -710,7 +753,7 @@ spa_remove(spa_t *spa)
        spa_stats_destroy(spa);
        spa_config_lock_destroy(spa);
 
-       for (t = 0; t < TXG_SIZE; t++)
+       for (int t = 0; t < TXG_SIZE; t++)
                bplist_destroy(&spa->spa_free_bplist[t]);
 
        zio_checksum_templates_free(spa);
@@ -1077,9 +1120,10 @@ spa_vdev_config_enter(spa_t *spa)
 void
 spa_vdev_config_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error, char *tag)
 {
+       ASSERT(MUTEX_HELD(&spa_namespace_lock));
+
        int config_changed = B_FALSE;
 
-       ASSERT(MUTEX_HELD(&spa_namespace_lock));
        ASSERT(txg > spa_last_synced_txg(spa));
 
        spa->spa_pending_vdev = NULL;
@@ -1129,7 +1173,7 @@ spa_vdev_config_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error, char *tag)
         * If the config changed, update the config cache.
         */
        if (config_changed)
-               spa_config_sync(spa, B_FALSE, B_TRUE);
+               spa_write_cachefile(spa, B_FALSE, B_TRUE);
 }
 
 /*
@@ -1221,7 +1265,7 @@ spa_vdev_state_exit(spa_t *spa, vdev_t *vd, int error)
         */
        if (config_changed) {
                mutex_enter(&spa_namespace_lock);
-               spa_config_sync(spa, B_FALSE, B_TRUE);
+               spa_write_cachefile(spa, B_FALSE, B_TRUE);
                mutex_exit(&spa_namespace_lock);
        }
 
@@ -1299,7 +1343,7 @@ spa_rename(const char *name, const char *newname)
        /*
         * Sync the updated config cache.
         */
-       spa_config_sync(spa, B_FALSE, B_TRUE);
+       spa_write_cachefile(spa, B_FALSE, B_TRUE);
 
        spa_close(spa, FTAG);
 
@@ -1384,6 +1428,9 @@ spa_get_random(uint64_t range)
 
        ASSERT(range != 0);
 
+       if (range == 1)
+               return (0);
+
        (void) random_get_pseudo_bytes((void *)&r, sizeof (uint64_t));
 
        return (r % range);
@@ -1465,7 +1512,7 @@ zfs_panic_recover(const char *fmt, ...)
  * lowercase hexadecimal numbers that don't overflow.
  */
 uint64_t
-strtonum(const char *str, char **nptr)
+zfs_strtonum(const char *str, char **nptr)
 {
        uint64_t val = 0;
        char c;
@@ -1515,6 +1562,12 @@ spa_is_initializing(spa_t *spa)
        return (spa->spa_is_initializing);
 }
 
+boolean_t
+spa_indirect_vdevs_loaded(spa_t *spa)
+{
+       return (spa->spa_indirect_vdevs_loaded);
+}
+
 blkptr_t *
 spa_get_rootblkptr(spa_t *spa)
 {
@@ -1668,18 +1721,45 @@ spa_get_dspace(spa_t *spa)
        return (spa->spa_dspace);
 }
 
+uint64_t
+spa_get_checkpoint_space(spa_t *spa)
+{
+       return (spa->spa_checkpoint_info.sci_dspace);
+}
+
 void
 spa_update_dspace(spa_t *spa)
 {
        spa->spa_dspace = metaslab_class_get_dspace(spa_normal_class(spa)) +
            ddt_get_dedup_dspace(spa);
+       if (spa->spa_vdev_removal != NULL) {
+               /*
+                * We can't allocate from the removing device, so
+                * subtract its size.  This prevents the DMU/DSL from
+                * filling up the (now smaller) pool while we are in the
+                * middle of removing the device.
+                *
+                * Note that the DMU/DSL doesn't actually know or care
+                * how much space is allocated (it does its own tracking
+                * of how much space has been logically used).  So it
+                * doesn't matter that the data we are moving may be
+                * allocated twice (on the old device and the new
+                * device).
+                */
+               spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
+               vdev_t *vd =
+                   vdev_lookup_top(spa, spa->spa_vdev_removal->svr_vdev_id);
+               spa->spa_dspace -= spa_deflate(spa) ?
+                   vd->vdev_stat.vs_dspace : vd->vdev_stat.vs_space;
+               spa_config_exit(spa, SCL_VDEV, FTAG);
+       }
 }
 
 /*
  * Return the failure mode that has been set to this pool. The default
  * behavior will be to block all I/Os when a complete failure occurs.
  */
-uint8_t
+uint64_t
 spa_get_failmode(spa_t *spa)
 {
        return (spa->spa_failmode);
@@ -1688,7 +1768,7 @@ spa_get_failmode(spa_t *spa)
 boolean_t
 spa_suspended(spa_t *spa)
 {
-       return (spa->spa_suspended);
+       return (spa->spa_suspended != ZIO_SUSPEND_NONE);
 }
 
 uint64_t
@@ -1768,6 +1848,31 @@ spa_deadman_synctime(spa_t *spa)
        return (spa->spa_deadman_synctime);
 }
 
+uint64_t
+spa_deadman_ziotime(spa_t *spa)
+{
+       return (spa->spa_deadman_ziotime);
+}
+
+uint64_t
+spa_get_deadman_failmode(spa_t *spa)
+{
+       return (spa->spa_deadman_failmode);
+}
+
+void
+spa_set_deadman_failmode(spa_t *spa, const char *failmode)
+{
+       if (strcmp(failmode, "wait") == 0)
+               spa->spa_deadman_failmode = ZIO_FAILURE_MODE_WAIT;
+       else if (strcmp(failmode, "continue") == 0)
+               spa->spa_deadman_failmode = ZIO_FAILURE_MODE_CONTINUE;
+       else if (strcmp(failmode, "panic") == 0)
+               spa->spa_deadman_failmode = ZIO_FAILURE_MODE_PANIC;
+       else
+               spa->spa_deadman_failmode = ZIO_FAILURE_MODE_WAIT;
+}
+
 uint64_t
 dva_get_dsize_sync(spa_t *spa, const dva_t *dva)
 {
@@ -1790,9 +1895,8 @@ uint64_t
 bp_get_dsize_sync(spa_t *spa, const blkptr_t *bp)
 {
        uint64_t dsize = 0;
-       int d;
 
-       for (d = 0; d < BP_GET_NDVAS(bp); d++)
+       for (int d = 0; d < BP_GET_NDVAS(bp); d++)
                dsize += dva_get_dsize_sync(spa, &bp->blk_dva[d]);
 
        return (dsize);
@@ -1802,11 +1906,10 @@ uint64_t
 bp_get_dsize(spa_t *spa, const blkptr_t *bp)
 {
        uint64_t dsize = 0;
-       int d;
 
        spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
 
-       for (d = 0; d < BP_GET_NDVAS(bp); d++)
+       for (int d = 0; d < BP_GET_NDVAS(bp); d++)
                dsize += dva_get_dsize_sync(spa, &bp->blk_dva[d]);
 
        spa_config_exit(spa, SCL_VDEV, FTAG);
@@ -1884,6 +1987,7 @@ spa_init(int mode)
        dmu_init();
        zil_init();
        vdev_cache_stat_init();
+       vdev_mirror_stat_init();
        vdev_raidz_math_init();
        vdev_file_init();
        zfs_prop_init();
@@ -1891,6 +1995,7 @@ spa_init(int mode)
        zpool_feature_init();
        spa_config_load();
        l2arc_start();
+       scan_init();
        qat_init();
 }
 
@@ -1903,6 +2008,7 @@ spa_fini(void)
 
        vdev_file_fini();
        vdev_cache_stat_fini();
+       vdev_mirror_stat_fini();
        vdev_raidz_math_fini();
        zil_fini();
        dmu_fini();
@@ -1913,6 +2019,7 @@ spa_fini(void)
        unique_fini();
        refcount_fini();
        fm_fini();
+       scan_fini();
        qat_fini();
 
        avl_destroy(&spa_namespace_avl);
@@ -1957,7 +2064,7 @@ spa_is_root(spa_t *spa)
 boolean_t
 spa_writeable(spa_t *spa)
 {
-       return (!!(spa->spa_mode & FWRITE));
+       return (!!(spa->spa_mode & FWRITE) && spa->spa_trust_config);
 }
 
 /*
@@ -1967,7 +2074,8 @@ spa_writeable(spa_t *spa)
 boolean_t
 spa_has_pending_synctask(spa_t *spa)
 {
-       return (!txg_all_lists_empty(&spa->spa_dsl_pool->dp_sync_tasks));
+       return (!txg_all_lists_empty(&spa->spa_dsl_pool->dp_sync_tasks) ||
+           !txg_all_lists_empty(&spa->spa_dsl_pool->dp_early_sync_tasks));
 }
 
 int
@@ -2014,6 +2122,7 @@ spa_scan_stat_init(spa_t *spa)
                spa->spa_scan_pass_scrub_pause = 0;
        spa->spa_scan_pass_scrub_spent_paused = 0;
        spa->spa_scan_pass_exam = 0;
+       spa->spa_scan_pass_issued = 0;
        vdev_scan_stat_init(spa->spa_root_vdev);
 }
 
@@ -2031,6 +2140,7 @@ spa_scan_get_stats(spa_t *spa, pool_scan_stat_t *ps)
 
        /* data stored on disk */
        ps->pss_func = scn->scn_phys.scn_func;
+       ps->pss_state = scn->scn_phys.scn_state;
        ps->pss_start_time = scn->scn_phys.scn_start_time;
        ps->pss_end_time = scn->scn_phys.scn_end_time;
        ps->pss_to_examine = scn->scn_phys.scn_to_examine;
@@ -2038,23 +2148,19 @@ spa_scan_get_stats(spa_t *spa, pool_scan_stat_t *ps)
        ps->pss_to_process = scn->scn_phys.scn_to_process;
        ps->pss_processed = scn->scn_phys.scn_processed;
        ps->pss_errors = scn->scn_phys.scn_errors;
-       ps->pss_state = scn->scn_phys.scn_state;
 
        /* data not stored on disk */
-       ps->pss_pass_start = spa->spa_scan_pass_start;
        ps->pss_pass_exam = spa->spa_scan_pass_exam;
+       ps->pss_pass_start = spa->spa_scan_pass_start;
        ps->pss_pass_scrub_pause = spa->spa_scan_pass_scrub_pause;
        ps->pss_pass_scrub_spent_paused = spa->spa_scan_pass_scrub_spent_paused;
+       ps->pss_pass_issued = spa->spa_scan_pass_issued;
+       ps->pss_issued =
+           scn->scn_issued_before_pass + spa->spa_scan_pass_issued;
 
        return (0);
 }
 
-boolean_t
-spa_debug_enabled(spa_t *spa)
-{
-       return (spa->spa_debug);
-}
-
 int
 spa_maxblocksize(spa_t *spa)
 {
@@ -2064,6 +2170,49 @@ spa_maxblocksize(spa_t *spa)
                return (SPA_OLD_MAXBLOCKSIZE);
 }
 
+
+/*
+ * Returns the txg that the last device removal completed. No indirect mappings
+ * have been added since this txg.
+ */
+uint64_t
+spa_get_last_removal_txg(spa_t *spa)
+{
+       uint64_t vdevid;
+       uint64_t ret = -1ULL;
+
+       spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
+       /*
+        * sr_prev_indirect_vdev is only modified while holding all the
+        * config locks, so it is sufficient to hold SCL_VDEV as reader when
+        * examining it.
+        */
+       vdevid = spa->spa_removing_phys.sr_prev_indirect_vdev;
+
+       while (vdevid != -1ULL) {
+               vdev_t *vd = vdev_lookup_top(spa, vdevid);
+               vdev_indirect_births_t *vib = vd->vdev_indirect_births;
+
+               ASSERT3P(vd->vdev_ops, ==, &vdev_indirect_ops);
+
+               /*
+                * If the removal did not remap any data, we don't care.
+                */
+               if (vdev_indirect_births_count(vib) != 0) {
+                       ret = vdev_indirect_births_last_entry_txg(vib);
+                       break;
+               }
+
+               vdevid = vd->vdev_indirect_config.vic_prev_indirect_vdev;
+       }
+       spa_config_exit(spa, SCL_VDEV, FTAG);
+
+       IMPLY(ret != -1ULL,
+           spa_feature_is_active(spa, SPA_FEATURE_DEVICE_REMOVAL));
+
+       return (ret);
+}
+
 int
 spa_maxdnodesize(spa_t *spa)
 {
@@ -2073,7 +2222,216 @@ spa_maxdnodesize(spa_t *spa)
                return (DNODE_MIN_SIZE);
 }
 
-#if defined(_KERNEL) && defined(HAVE_SPL)
+boolean_t
+spa_multihost(spa_t *spa)
+{
+       return (spa->spa_multihost ? B_TRUE : B_FALSE);
+}
+
+unsigned long
+spa_get_hostid(void)
+{
+       unsigned long myhostid;
+
+#ifdef _KERNEL
+       myhostid = zone_get_hostid(NULL);
+#else  /* _KERNEL */
+       /*
+        * We're emulating the system's hostid in userland, so
+        * we can't use zone_get_hostid().
+        */
+       (void) ddi_strtoul(hw_serial, NULL, 10, &myhostid);
+#endif /* _KERNEL */
+
+       return (myhostid);
+}
+
+boolean_t
+spa_trust_config(spa_t *spa)
+{
+       return (spa->spa_trust_config);
+}
+
+uint64_t
+spa_missing_tvds_allowed(spa_t *spa)
+{
+       return (spa->spa_missing_tvds_allowed);
+}
+
+void
+spa_set_missing_tvds(spa_t *spa, uint64_t missing)
+{
+       spa->spa_missing_tvds = missing;
+}
+
+/*
+ * Return the pool state string ("ONLINE", "DEGRADED", "SUSPENDED", etc).
+ */
+const char *
+spa_state_to_name(spa_t *spa)
+{
+       vdev_state_t state = spa->spa_root_vdev->vdev_state;
+       vdev_aux_t aux = spa->spa_root_vdev->vdev_stat.vs_aux;
+
+       if (spa_suspended(spa) &&
+           (spa_get_failmode(spa) != ZIO_FAILURE_MODE_CONTINUE))
+               return ("SUSPENDED");
+
+       switch (state) {
+       case VDEV_STATE_CLOSED:
+       case VDEV_STATE_OFFLINE:
+               return ("OFFLINE");
+       case VDEV_STATE_REMOVED:
+               return ("REMOVED");
+       case VDEV_STATE_CANT_OPEN:
+               if (aux == VDEV_AUX_CORRUPT_DATA || aux == VDEV_AUX_BAD_LOG)
+                       return ("FAULTED");
+               else if (aux == VDEV_AUX_SPLIT_POOL)
+                       return ("SPLIT");
+               else
+                       return ("UNAVAIL");
+       case VDEV_STATE_FAULTED:
+               return ("FAULTED");
+       case VDEV_STATE_DEGRADED:
+               return ("DEGRADED");
+       case VDEV_STATE_HEALTHY:
+               return ("ONLINE");
+       default:
+               break;
+       }
+
+       return ("UNKNOWN");
+}
+
+boolean_t
+spa_top_vdevs_spacemap_addressable(spa_t *spa)
+{
+       vdev_t *rvd = spa->spa_root_vdev;
+       for (uint64_t c = 0; c < rvd->vdev_children; c++) {
+               if (!vdev_is_spacemap_addressable(rvd->vdev_child[c]))
+                       return (B_FALSE);
+       }
+       return (B_TRUE);
+}
+
+boolean_t
+spa_has_checkpoint(spa_t *spa)
+{
+       return (spa->spa_checkpoint_txg != 0);
+}
+
+boolean_t
+spa_importing_readonly_checkpoint(spa_t *spa)
+{
+       return ((spa->spa_import_flags & ZFS_IMPORT_CHECKPOINT) &&
+           spa->spa_mode == FREAD);
+}
+
+uint64_t
+spa_min_claim_txg(spa_t *spa)
+{
+       uint64_t checkpoint_txg = spa->spa_uberblock.ub_checkpoint_txg;
+
+       if (checkpoint_txg != 0)
+               return (checkpoint_txg + 1);
+
+       return (spa->spa_first_txg);
+}
+
+/*
+ * If there is a checkpoint, async destroys may consume more space from
+ * the pool instead of freeing it. In an attempt to save the pool from
+ * getting suspended when it is about to run out of space, we stop
+ * processing async destroys.
+ */
+boolean_t
+spa_suspend_async_destroy(spa_t *spa)
+{
+       dsl_pool_t *dp = spa_get_dsl(spa);
+
+       uint64_t unreserved = dsl_pool_unreserved_space(dp,
+           ZFS_SPACE_CHECK_EXTRA_RESERVED);
+       uint64_t used = dsl_dir_phys(dp->dp_root_dir)->dd_used_bytes;
+       uint64_t avail = (unreserved > used) ? (unreserved - used) : 0;
+
+       if (spa_has_checkpoint(spa) && avail == 0)
+               return (B_TRUE);
+
+       return (B_FALSE);
+}
+
+#if defined(_KERNEL)
+
+#include <linux/mod_compat.h>
+
+static int
+param_set_deadman_failmode(const char *val, zfs_kernel_param_t *kp)
+{
+       spa_t *spa = NULL;
+       char *p;
+
+       if (val == NULL)
+               return (SET_ERROR(-EINVAL));
+
+       if ((p = strchr(val, '\n')) != NULL)
+               *p = '\0';
+
+       if (strcmp(val, "wait") != 0 && strcmp(val, "continue") != 0 &&
+           strcmp(val, "panic"))
+               return (SET_ERROR(-EINVAL));
+
+       if (spa_mode_global != 0) {
+               mutex_enter(&spa_namespace_lock);
+               while ((spa = spa_next(spa)) != NULL)
+                       spa_set_deadman_failmode(spa, val);
+               mutex_exit(&spa_namespace_lock);
+       }
+
+       return (param_set_charp(val, kp));
+}
+
+static int
+param_set_deadman_ziotime(const char *val, zfs_kernel_param_t *kp)
+{
+       spa_t *spa = NULL;
+       int error;
+
+       error = param_set_ulong(val, kp);
+       if (error < 0)
+               return (SET_ERROR(error));
+
+       if (spa_mode_global != 0) {
+               mutex_enter(&spa_namespace_lock);
+               while ((spa = spa_next(spa)) != NULL)
+                       spa->spa_deadman_ziotime =
+                           MSEC2NSEC(zfs_deadman_ziotime_ms);
+               mutex_exit(&spa_namespace_lock);
+       }
+
+       return (0);
+}
+
+static int
+param_set_deadman_synctime(const char *val, zfs_kernel_param_t *kp)
+{
+       spa_t *spa = NULL;
+       int error;
+
+       error = param_set_ulong(val, kp);
+       if (error < 0)
+               return (SET_ERROR(error));
+
+       if (spa_mode_global != 0) {
+               mutex_enter(&spa_namespace_lock);
+               while ((spa = spa_next(spa)) != NULL)
+                       spa->spa_deadman_synctime =
+                           MSEC2NSEC(zfs_deadman_synctime_ms);
+               mutex_exit(&spa_namespace_lock);
+       }
+
+       return (0);
+}
+
 /* Namespace manipulation */
 EXPORT_SYMBOL(spa_lookup);
 EXPORT_SYMBOL(spa_add);
@@ -2151,6 +2509,15 @@ EXPORT_SYMBOL(spa_is_root);
 EXPORT_SYMBOL(spa_writeable);
 EXPORT_SYMBOL(spa_mode);
 EXPORT_SYMBOL(spa_namespace_lock);
+EXPORT_SYMBOL(spa_trust_config);
+EXPORT_SYMBOL(spa_missing_tvds_allowed);
+EXPORT_SYMBOL(spa_set_missing_tvds);
+EXPORT_SYMBOL(spa_state_to_name);
+EXPORT_SYMBOL(spa_importing_readonly_checkpoint);
+EXPORT_SYMBOL(spa_min_claim_txg);
+EXPORT_SYMBOL(spa_suspend_async_destroy);
+EXPORT_SYMBOL(spa_has_checkpoint);
+EXPORT_SYMBOL(spa_top_vdevs_spacemap_addressable);
 
 /* BEGIN CSTYLED */
 module_param(zfs_flags, uint, 0644);
@@ -2163,8 +2530,15 @@ module_param(zfs_free_leak_on_eio, int, 0644);
 MODULE_PARM_DESC(zfs_free_leak_on_eio,
        "Set to ignore IO errors during free and permanently leak the space");
 
-module_param(zfs_deadman_synctime_ms, ulong, 0644);
-MODULE_PARM_DESC(zfs_deadman_synctime_ms, "Expiration time in milliseconds");
+module_param_call(zfs_deadman_synctime_ms, param_set_deadman_synctime,
+    param_get_ulong, &zfs_deadman_synctime_ms, 0644);
+MODULE_PARM_DESC(zfs_deadman_synctime_ms,
+       "Pool sync expiration time in milliseconds");
+
+module_param_call(zfs_deadman_ziotime_ms, param_set_deadman_ziotime,
+    param_get_ulong, &zfs_deadman_ziotime_ms, 0644);
+MODULE_PARM_DESC(zfs_deadman_ziotime_ms,
+       "IO expiration time in milliseconds");
 
 module_param(zfs_deadman_checktime_ms, ulong, 0644);
 MODULE_PARM_DESC(zfs_deadman_checktime_ms,
@@ -2173,6 +2547,10 @@ MODULE_PARM_DESC(zfs_deadman_checktime_ms,
 module_param(zfs_deadman_enabled, int, 0644);
 MODULE_PARM_DESC(zfs_deadman_enabled, "Enable deadman timer");
 
+module_param_call(zfs_deadman_failmode, param_set_deadman_failmode,
+    param_get_charp, &zfs_deadman_failmode, 0644);
+MODULE_PARM_DESC(zfs_deadman_failmode, "Failmode for deadman timer");
+
 module_param(spa_asize_inflation, int, 0644);
 MODULE_PARM_DESC(spa_asize_inflation,
        "SPA size estimate multiplication factor");