1 files changed, 35 insertions, 1 deletions

diff --git a/storage/maria/ma_trnman.h b/storage/maria/ma_trnman.h
index 9bfd1f0d047..5b6d0e9f60d 100644
--- a/storage/maria/ma_trnman.h
+++ b/storage/maria/ma_trnman.h
@@ -18,7 +18,7 @@
 
 /**
    Sets table's trn and prints debug information
-   Links table into used_instances if new_trn is not 0
+   Links table into new_trn->used_instances
 
    @param tbl              MARIA_HA of table
    @param newtrn           what to put into tbl->trn
@@ -34,7 +34,10 @@ static inline void _ma_set_trn_for_table(MARIA_HA *tbl, TRN *newtrn)
 
   tbl->trn= newtrn;
   /* Link into used list */
+  if (newtrn->used_instances)
+    ((MARIA_HA*) newtrn->used_instances)->trn_prev= &tbl->trn_next;
   tbl->trn_next= (MARIA_HA*) newtrn->used_instances;
+  tbl->trn_prev= (MARIA_HA**) &newtrn->used_instances;
   newtrn->used_instances= tbl;
 }
 
@@ -49,6 +52,8 @@ static inline void _ma_set_tmp_trn_for_table(MARIA_HA *tbl, TRN *newtrn)
   DBUG_PRINT("info",("table: %p  trn: %p -> %p",
                      tbl, tbl->trn, newtrn));
   tbl->trn= newtrn;
+  tbl->trn_prev= 0;
+  tbl->trn_next= 0;               /* To avoid assert in ha_maria::close() */
 }
 
 
@@ -59,7 +64,36 @@ static inline void _ma_set_tmp_trn_for_table(MARIA_HA *tbl, TRN *newtrn)
 static inline void _ma_reset_trn_for_table(MARIA_HA *tbl)
 {
   DBUG_PRINT("info",("table: %p  trn: %p -> NULL", tbl, tbl->trn));
+
+  /* The following is only false if tbl->trn == &dummy_transaction_object */
+  if (tbl->trn_prev)
+  {
+    if (tbl->trn_next)
+      tbl->trn_next->trn_prev= tbl->trn_prev;
+    *tbl->trn_prev= tbl->trn_next;
+    tbl->trn_prev= 0;
+    tbl->trn_next= 0;
+  }
   tbl->trn= 0;
 }
 
+
+/*
+  Take over the used_instances link from a trn object
+  Reset the link in the trn object
+*/
+
+static inline void relink_trn_used_instances(MARIA_HA **used_tables, TRN *trn)
+{
+  if (likely(*used_tables= (MARIA_HA*) trn->used_instances))
+  {
+    /* Check that first back link is correct */
+    DBUG_ASSERT((*used_tables)->trn_prev == (MARIA_HA **)&trn->used_instances);
+
+    /* Fix back link to point to new base for the list */
+    (*used_tables)->trn_prev= used_tables;
+    trn->used_instances= 0;
+  }
+}
+
 #endif /* _ma_trnman_h */