Illumos 5314 - Remove "dbuf phys" db->db_data pointer aliases in ZFS

5314 Remove "dbuf phys" db->db_data pointer aliases in ZFS
Author: Justin T. Gibbs <[email protected]>
Reviewed by: Andriy Gapon <[email protected]>
Reviewed by: Matthew Ahrens <[email protected]>
Reviewed by: Will Andrews <[email protected]>
Approved by: Dan McDonald <[email protected]>

References:
  https://www.illumos.org/issues/5314
  https://github.com/illumos/illumos-gate/commit/c137962

Ported-by: Chris Dunlop <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>

1 files changed, 13 insertions, 12 deletions

diff --git a/module/zfs/dsl_userhold.c b/module/zfs/dsl_userhold.c
index 1d6c9df89..e2318d03b 100644
--- a/module/zfs/dsl_userhold.c
+++ b/module/zfs/dsl_userhold.c
@@ -64,10 +64,10 @@ dsl_dataset_user_hold_check_one(dsl_dataset_t *ds, const char *htag,
 		return (SET_ERROR(E2BIG));
 
 	/* tags must be unique (if ds already exists) */
-	if (ds != NULL && ds->ds_phys->ds_userrefs_obj != 0) {
+	if (ds != NULL && dsl_dataset_phys(ds)->ds_userrefs_obj != 0) {
 		uint64_t value;
 
-		error = zap_lookup(mos, ds->ds_phys->ds_userrefs_obj,
+		error = zap_lookup(mos, dsl_dataset_phys(ds)->ds_userrefs_obj,
 		    htag, 8, 1, &value);
 		if (error == 0)
 			error = SET_ERROR(EEXIST);
@@ -141,16 +141,16 @@ dsl_dataset_user_hold_sync_one_impl(nvlist_t *tmpholds, dsl_dataset_t *ds,
 
 	ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
 
-	if (ds->ds_phys->ds_userrefs_obj == 0) {
+	if (dsl_dataset_phys(ds)->ds_userrefs_obj == 0) {
 		/*
 		 * This is the first user hold for this dataset.  Create
 		 * the userrefs zap object.
 		 */
 		dmu_buf_will_dirty(ds->ds_dbuf, tx);
-		zapobj = ds->ds_phys->ds_userrefs_obj =
+		zapobj = dsl_dataset_phys(ds)->ds_userrefs_obj =
 		    zap_create(mos, DMU_OT_USERREFS, DMU_OT_NONE, 0, tx);
 	} else {
-		zapobj = ds->ds_phys->ds_userrefs_obj;
+		zapobj = dsl_dataset_phys(ds)->ds_userrefs_obj;
 	}
 	ds->ds_userrefs++;
 
@@ -362,7 +362,7 @@ dsl_dataset_user_release_check_one(dsl_dataset_user_release_arg_t *ddura,
 
 	numholds = 0;
 	mos = ds->ds_dir->dd_pool->dp_meta_objset;
-	zapobj = ds->ds_phys->ds_userrefs_obj;
+	zapobj = dsl_dataset_phys(ds)->ds_userrefs_obj;
 	VERIFY0(nvlist_alloc(&holds_found, NV_UNIQUE_NAME, KM_SLEEP));
 
 	for (pair = nvlist_next_nvpair(holds, NULL); pair != NULL;
@@ -400,7 +400,8 @@ dsl_dataset_user_release_check_one(dsl_dataset_user_release_arg_t *ddura,
 		numholds++;
 	}
 
-	if (DS_IS_DEFER_DESTROY(ds) && ds->ds_phys->ds_num_children == 1 &&
+	if (DS_IS_DEFER_DESTROY(ds) &&
+	    dsl_dataset_phys(ds)->ds_num_children == 1 &&
 	    ds->ds_userrefs == numholds) {
 		/* we need to destroy the snapshot as well */
 		if (dsl_dataset_long_held(ds)) {
@@ -488,8 +489,8 @@ dsl_dataset_user_release_sync_one(dsl_dataset_t *ds, nvlist_t *holds,
 		error = dsl_pool_user_release(dp, ds->ds_object, holdname, tx);
 		VERIFY(error == 0 || error == ENOENT);
 
-		VERIFY0(zap_remove(mos, ds->ds_phys->ds_userrefs_obj, holdname,
-		    tx));
+		VERIFY0(zap_remove(mos, dsl_dataset_phys(ds)->ds_userrefs_obj,
+		    holdname, tx));
 		ds->ds_userrefs--;
 
 		spa_history_log_internal_ds(ds, "release", tx,
@@ -519,7 +520,7 @@ dsl_dataset_user_release_sync(void *arg, dmu_tx_t *tx)
 		    fnvpair_value_nvlist(pair), tx);
 		if (nvlist_exists(ddura->ddura_todelete, name)) {
 			ASSERT(ds->ds_userrefs == 0 &&
-			    ds->ds_phys->ds_num_children == 1 &&
+			    dsl_dataset_phys(ds)->ds_num_children == 1 &&
 			    DS_IS_DEFER_DESTROY(ds));
 			dsl_destroy_snapshot_sync_impl(ds, B_FALSE, tx);
 		}
@@ -651,13 +652,13 @@ dsl_dataset_get_holds(const char *dsname, nvlist_t *nvl)
 		return (err);
 	}
 
-	if (ds->ds_phys->ds_userrefs_obj != 0) {
+	if (dsl_dataset_phys(ds)->ds_userrefs_obj != 0) {
 		zap_attribute_t *za;
 		zap_cursor_t zc;
 
 		za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
 		for (zap_cursor_init(&zc, ds->ds_dir->dd_pool->dp_meta_objset,
-		    ds->ds_phys->ds_userrefs_obj);
+		    dsl_dataset_phys(ds)->ds_userrefs_obj);
 		    zap_cursor_retrieve(&zc, za) == 0;
 		    zap_cursor_advance(&zc)) {
 			fnvlist_add_uint64(nvl, za->za_name,