Revert "dmu_objset_userquota_get_ids uses dn_bonus unsafely"

This reverts commit 5f8e1e850522ee5cd37366427da4b4101a71c8a8.  It
was determined that this patch introduced the quota regression
described in #3789.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #3443
Issue #3789

diff --git a/module/zfs/dmu_objset.c b/module/zfs/dmu_objset.c
index 4d5baf8da84b3f26b08f92cfb7106687776ce192..b3168a8561419ee3f0bda66ad34be3dc312c8ba5 100644 (file)
--- a/module/zfs/dmu_objset.c
+++ b/module/zfs/dmu_objset.c
@@ -1342,7 +1342,6 @@ dmu_objset_userquota_get_ids(dnode_t *dn, boolean_t before, dmu_tx_t *tx)
        int flags = dn->dn_id_flags;
        int error;
        boolean_t have_spill = B_FALSE;
-       boolean_t have_bonus = B_FALSE;
 
        if (!dmu_objset_userused_enabled(dn->dn_objset))
                return;
@@ -1354,21 +1353,8 @@ dmu_objset_userquota_get_ids(dnode_t *dn, boolean_t before, dmu_tx_t *tx)
        if (before && dn->dn_bonuslen != 0)
                data = DN_BONUS(dn->dn_phys);
        else if (!before && dn->dn_bonuslen != 0) {
-               db = dn->dn_bonus;
-               if (db != NULL) {
-                       if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) {
-                               have_bonus = dbuf_try_add_ref((dmu_buf_t *)db,
-                                   dn->dn_objset, dn->dn_object,
-                                   DMU_BONUS_BLKID, FTAG);
-
-                               /*
-                                * The hold will fail if the buffer is
-                                * being evicted due to unlink, in which
-                                * case nothing needs to be done.
-                                */
-                               if (!have_bonus)
-                                       return;
-                       }
+               if (dn->dn_bonus) {
+                       db = dn->dn_bonus;
                        mutex_enter(&db->db_mtx);
                        data = dmu_objset_userquota_find_data(db, tx);
                } else {
@@ -1443,7 +1429,7 @@ dmu_objset_userquota_get_ids(dnode_t *dn, boolean_t before, dmu_tx_t *tx)
                dn->dn_id_flags |= DN_ID_CHKED_BONUS;
        }
        mutex_exit(&dn->dn_mtx);
-       if (have_spill || have_bonus)
+       if (have_spill)
                dmu_buf_rele((dmu_buf_t *)db, FTAG);
 }