Fix zpool on zvol deadlock

[zfs.git] / module / zfs / ddt.c

diff --git a/module/zfs/ddt.c b/module/zfs/ddt.c
index f93024d..ef86861 100644 (file)
--- a/module/zfs/ddt.c
+++ b/module/zfs/ddt.c
@@ -21,6 +21,7 @@
 
 /*
  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #include <sys/zfs_context.h>
@@ -82,13 +83,14 @@ ddt_object_destroy(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
        spa_t *spa = ddt->ddt_spa;
        objset_t *os = ddt->ddt_os;
        uint64_t *objectp = &ddt->ddt_object[type][class];
+       uint64_t count;
        char name[DDT_NAMELEN];
 
        ddt_object_name(ddt, type, class, name);
 
        ASSERT(*objectp != 0);
-       ASSERT(ddt_object_count(ddt, type, class) == 0);
        ASSERT(ddt_histogram_empty(&ddt->ddt_histogram[type][class]));
+       VERIFY(ddt_object_count(ddt, type, class, &count) == 0 && count == 0);
        VERIFY(zap_remove(os, DMU_POOL_DIRECTORY_OBJECT, name, tx) == 0);
        VERIFY(zap_remove(os, spa->spa_ddt_stat_object, name, tx) == 0);
        VERIFY(ddt_ops[type]->ddt_op_destroy(os, *objectp, tx) == 0);
@@ -102,6 +104,7 @@ ddt_object_load(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
 {
        ddt_object_t *ddo = &ddt->ddt_object_stats[type][class];
        dmu_object_info_t doi;
+       uint64_t count;
        char name[DDT_NAMELEN];
        int error;
 
@@ -124,7 +127,11 @@ ddt_object_load(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
        if (error)
                return (error);
 
-       ddo->ddo_count = ddt_object_count(ddt, type, class);
+       error = ddt_object_count(ddt, type, class, &count);
+       if (error)
+               return (error);
+
+       ddo->ddo_count = count;
        ddo->ddo_dspace = doi.doi_physical_blocks_512 << 9;
        ddo->ddo_mspace = doi.doi_fill_count * doi.doi_data_block_size;
 
@@ -138,6 +145,7 @@ ddt_object_sync(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
 {
        ddt_object_t *ddo = &ddt->ddt_object_stats[type][class];
        dmu_object_info_t doi;
+       uint64_t count;
        char name[DDT_NAMELEN];
 
        ddt_object_name(ddt, type, class, name);
@@ -150,8 +158,9 @@ ddt_object_sync(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
         * Cache DDT statistics; this is the only time they'll change.
         */
        VERIFY(ddt_object_info(ddt, type, class, &doi) == 0);
+       VERIFY(ddt_object_count(ddt, type, class, &count) == 0);
 
-       ddo->ddo_count = ddt_object_count(ddt, type, class);
+       ddo->ddo_count = count;
        ddo->ddo_dspace = doi.doi_physical_blocks_512 << 9;
        ddo->ddo_mspace = doi.doi_fill_count * doi.doi_data_block_size;
 }
@@ -208,13 +217,14 @@ ddt_object_walk(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
            ddt->ddt_object[type][class], dde, walk));
 }
 
-uint64_t
-ddt_object_count(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
+int
+ddt_object_count(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
+    uint64_t *count)
 {
        ASSERT(ddt_object_exists(ddt, type, class));
 
        return (ddt_ops[type]->ddt_op_count(ddt->ddt_os,
-           ddt->ddt_object[type][class]));
+           ddt->ddt_object[type][class], count));
 }
 
 int
@@ -653,7 +663,7 @@ ddt_alloc(const ddt_key_t *ddk)
        ddt_entry_t *dde;
 
        /* XXX: Move to a slab */
-       dde = kmem_zalloc(sizeof (ddt_entry_t), KM_SLEEP);
+       dde = kmem_zalloc(sizeof (ddt_entry_t), KM_PUSHPAGE);
        cv_init(&dde->dde_cv, NULL, CV_DEFAULT, NULL);
 
        dde->dde_key = *ddk;
@@ -802,7 +812,7 @@ ddt_table_alloc(spa_t *spa, enum zio_checksum c)
        ddt_t *ddt;
 
        /* XXX: Move to a slab */
-       ddt = kmem_zalloc(sizeof (*ddt), KM_SLEEP | KM_NODEBUG);
+       ddt = kmem_zalloc(sizeof (*ddt), KM_PUSHPAGE | KM_NODEBUG);
 
        mutex_init(&ddt->ddt_lock, NULL, MUTEX_DEFAULT, NULL);
        avl_create(&ddt->ddt_tree, ddt_entry_compare,
@@ -904,7 +914,7 @@ ddt_class_contains(spa_t *spa, enum ddt_class max_class, const blkptr_t *bp)
                return (B_TRUE);
 
        ddt = spa->spa_ddt[BP_GET_CHECKSUM(bp)];
-       dde = kmem_alloc(sizeof(ddt_entry_t), KM_SLEEP);
+       dde = kmem_alloc(sizeof(ddt_entry_t), KM_PUSHPAGE);
 
        ddt_key_fill(&(dde->dde_key), bp);
 
@@ -1111,11 +1121,9 @@ ddt_sync_table(ddt_t *ddt, dmu_tx_t *tx, uint64_t txg)
        ASSERT(spa->spa_uberblock.ub_version >= SPA_VERSION_DEDUP);
 
        if (spa->spa_ddt_stat_object == 0) {
-               spa->spa_ddt_stat_object = zap_create(ddt->ddt_os,
-                   DMU_OT_DDT_STATS, DMU_OT_NONE, 0, tx);
-               VERIFY(zap_add(ddt->ddt_os, DMU_POOL_DIRECTORY_OBJECT,
-                   DMU_POOL_DDT_STATS, sizeof (uint64_t), 1,
-                   &spa->spa_ddt_stat_object, tx) == 0);
+               spa->spa_ddt_stat_object = zap_create_link(ddt->ddt_os,
+                   DMU_OT_DDT_STATS, DMU_POOL_DIRECTORY_OBJECT,
+                   DMU_POOL_DDT_STATS, tx);
        }
 
        while ((dde = avl_destroy_nodes(&ddt->ddt_tree, &cookie)) != NULL) {
@@ -1124,11 +1132,13 @@ ddt_sync_table(ddt_t *ddt, dmu_tx_t *tx, uint64_t txg)
        }
 
        for (type = 0; type < DDT_TYPES; type++) {
-               uint64_t count = 0;
+               uint64_t add, count = 0;
                for (class = 0; class < DDT_CLASSES; class++) {
                        if (ddt_object_exists(ddt, type, class)) {
                                ddt_object_sync(ddt, type, class, tx);
-                               count += ddt_object_count(ddt, type, class);
+                               VERIFY(ddt_object_count(ddt, type, class,
+                                   &add) == 0);
+                               count += add;
                        }
                }
                for (class = 0; class < DDT_CLASSES; class++) {