[illumos-gate merge]

commit 1d32ba663e202c24a5a1f2e5aef83fffb447cb7f
    7290 ZFS test suite needs to control what utilities it can run
commit f4fb84c03b3f4c46dab36872e953dd3c27317c3a
    7576 Print the correct size of loader.efi when failing to load it into memory.
commit 40510e8eba18690b9a9843b26393725eeb0f1dac
    6676 Race between unique_insert() and unique_remove() causes ZFS fsid change

1 files changed, 30 insertions, 5 deletions

diff --git a/usr/src/uts/common/fs/zfs/dsl_dataset.c b/usr/src/uts/common/fs/zfs/dsl_dataset.c
index b143b3900a..74409fecaa 100644
--- a/usr/src/uts/common/fs/zfs/dsl_dataset.c
+++ b/usr/src/uts/common/fs/zfs/dsl_dataset.c
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
+ * Copyright (c) 2011, 2016 by Delphix. All rights reserved.
  * Copyright (c) 2014, Joyent, Inc. All rights reserved.
  * Copyright (c) 2014 RackTop Systems.
  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
@@ -269,16 +269,30 @@ dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
 	return (B_TRUE);
 }
 
+/*
+ * We have to release the fsid syncronously or we risk that a subsequent
+ * mount of the same dataset will fail to unique_insert the fsid.  This
+ * failure would manifest itself as the fsid of this dataset changing
+ * between mounts which makes NFS clients quite unhappy.
+ */
 static void
-dsl_dataset_evict(void *dbu)
+dsl_dataset_evict_sync(void *dbu)
 {
 	dsl_dataset_t *ds = dbu;
 
 	ASSERT(ds->ds_owner == NULL);
 
-	ds->ds_dbuf = NULL;
-
 	unique_remove(ds->ds_fsid_guid);
+}
+
+static void
+dsl_dataset_evict_async(void *dbu)
+{
+	dsl_dataset_t *ds = dbu;
+
+	ASSERT(ds->ds_owner == NULL);
+
+	ds->ds_dbuf = NULL;
 
 	if (ds->ds_objset != NULL)
 		dmu_objset_evict(ds->ds_objset);
@@ -514,7 +528,8 @@ dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
 			ds->ds_reserved = ds->ds_quota = 0;
 		}
 
-		dmu_buf_init_user(&ds->ds_dbu, dsl_dataset_evict, &ds->ds_dbuf);
+		dmu_buf_init_user(&ds->ds_dbu, dsl_dataset_evict_sync,
+		    dsl_dataset_evict_async, &ds->ds_dbuf);
 		if (err == 0)
 			winner = dmu_buf_set_user_ie(dbuf, &ds->ds_dbu);
 
@@ -537,6 +552,16 @@ dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
 		} else {
 			ds->ds_fsid_guid =
 			    unique_insert(dsl_dataset_phys(ds)->ds_fsid_guid);
+			if (ds->ds_fsid_guid !=
+			    dsl_dataset_phys(ds)->ds_fsid_guid) {
+				zfs_dbgmsg("ds_fsid_guid changed from "
+				    "%llx to %llx for pool %s dataset id %llu",
+				    (long long)
+				    dsl_dataset_phys(ds)->ds_fsid_guid,
+				    (long long)ds->ds_fsid_guid,
+				    spa_name(dp->dp_spa),
+				    dsobj);
+			}
 		}
 	}
 	ASSERT3P(ds->ds_dbuf, ==, dbuf);