MDEV-4786 merge 10.0-monty -> 10.0

remove TDC_RT_REMOVE_NOT_OWN_AND_MARK_NOT_USABLE

mysql-test/r/myisam-metadata.result

-DROP TABLE IF EXISTS t1;
-CREATE TABLE t1 (
-id INT PRIMARY KEY,
-a VARCHAR(100),
-INDEX(a)
-) ENGINE=MyISAM;
-ALTER TABLE t1 DISABLE KEYS;
-SET debug_sync= 'myisam_before_repair_by_sort SIGNAL waiting WAIT_FOR go';
-ALTER TABLE t1 ENABLE KEYS;
-SET debug_sync= 'now WAIT_FOR waiting';
-SET debug_sync= 'now SIGNAL go';
-SHOW TABLE STATUS LIKE 't1';
-Name	Engine	Version	Row_format	Rows	Avg_row_length	Data_length	Max_data_length	Index_length	Data_free	Auto_increment	Create_time	Update_time	Check_time	Collation	Checksum	Create_options	Comment
-t1	MyISAM	10	Dynamic	100000	27	#	#	#	0	NULL	#	#	#	latin1_swedish_ci	NULL		
-DROP TABLE t1;

mysql-test/t/myisam-metadata.test

-#
-# Test bugs in MyISAM that may cause problems for metadata
-#
-
---source include/big_test.inc
---source include/have_debug_sync.inc
-
---disable_warnings
-DROP TABLE IF EXISTS t1;
---enable_warnings
-
-#
-# LP:989055 - Querying myisam table metadata may corrupt the table
-#
-
-CREATE TABLE t1 (
-  id INT PRIMARY KEY,
-  a VARCHAR(100),
-  INDEX(a)
-) ENGINE=MyISAM;
-ALTER TABLE t1 DISABLE KEYS;
-
-let $1=100000;
---disable_query_log
-while ($1)
-{
- eval insert into t1 values($1, "line number $1");
- dec $1;
-}
---enable_query_log
-
---connect(con1,localhost,root,,)
-SET debug_sync= 'myisam_before_repair_by_sort SIGNAL waiting WAIT_FOR go';
-send
-  ALTER TABLE t1 ENABLE KEYS;
-
---connection default
-SET debug_sync= 'now WAIT_FOR waiting';
-SET debug_sync= 'now SIGNAL go';
-
---replace_column 7 # 8 # 9 # 12 # 13 # 14 #
-SHOW TABLE STATUS LIKE 't1';
-
---connection con1
---reap
---connection default
---disconnect con1
-DROP TABLE t1;

sql/mysqld.cc

@@ -7913,7 +7913,7 @@ static int mysql_init_variables(void)
   log_error_file_ptr= log_error_file;
   protocol_version= PROTOCOL_VERSION;
   what_to_log= ~ (1L << (uint) COM_TIME);
-  refresh_version= 2L;	/* Increments on each reload. 0 and 1 are reserved */
+  refresh_version= 1L;	/* Increments on each reload */
   denied_connections= 0;
   executed_events= 0;
   global_query_id= thread_id= 1L;

sql/sql_admin.cc

@@ -100,7 +100,6 @@ static int prepare_for_repair(THD *thd, TABLE_LIST *table_list,
   const char **ext;
   MY_STAT stat_info;
   Open_table_context ot_ctx(thd, (MYSQL_OPEN_IGNORE_FLUSH |
-                                  MYSQL_OPEN_FOR_REPAIR |
                                   MYSQL_OPEN_HAS_MDL_LOCK |
                                   MYSQL_LOCK_IGNORE_TIMEOUT));
   DBUG_ENTER("prepare_for_repair");
@@ -201,9 +200,7 @@ static int prepare_for_repair(THD *thd, TABLE_LIST *table_list,
       to close it, but leave it protected by exclusive metadata lock.
     */
     pos_in_locked_tables= table->pos_in_locked_tables;
-    if (wait_while_table_is_used(thd, table,
-                                 HA_EXTRA_PREPARE_FOR_FORCED_CLOSE,
-                                 TDC_RT_REMOVE_NOT_OWN_AND_MARK_NOT_USABLE))
+    if (wait_while_table_is_used(thd, table, HA_EXTRA_PREPARE_FOR_FORCED_CLOSE))
       goto end;
     /* Close table but don't remove from locked list */
     close_all_tables_for_name(thd, table_list->table->s,
@@ -608,10 +605,8 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
     */
     if (lock_type == TL_WRITE && !table->table->s->tmp_table)
     {
-      table->table->s->protect_against_usage();
       if (wait_while_table_is_used(thd, table->table,
-                                   HA_EXTRA_PREPARE_FOR_RENAME,
-                                   TDC_RT_REMOVE_NOT_OWN_AND_MARK_NOT_USABLE))
+                                   HA_EXTRA_PREPARE_FOR_RENAME))
         goto err;
       DEBUG_SYNC(thd, "after_admin_flush");
       /* Flush entries in the query cache involving this table. */

sql/sql_base.cc

@@ -1062,7 +1062,7 @@ bool close_cached_tables(THD *thd, TABLE_LIST *tables,
       if (share)
       {
         kill_delayed_threads_for_table(share);
-        /* tdc_remove_table() calls share->remove_from_cache_at_close() */
+        /* tdc_remove_table() also sets TABLE_SHARE::version to 0. */
         tdc_remove_table(thd, TDC_RT_REMOVE_UNUSED, table->db,
                          table->table_name, TRUE);
 	found=1;
@@ -2333,8 +2333,7 @@ bool rename_temporary_table(THD* thd, TABLE *table, const char *db,
 */
 
 bool wait_while_table_is_used(THD *thd, TABLE *table,
-                              enum ha_extra_function function,
-                              enum_tdc_remove_table_type remove_type)
+                              enum ha_extra_function function)
 {
   DBUG_ENTER("wait_while_table_is_used");
   DBUG_PRINT("enter", ("table: '%s'  share: 0x%lx  db_stat: %u  version: %lu",
@@ -2346,7 +2345,7 @@ bool wait_while_table_is_used(THD *thd, TABLE *table,
              thd->variables.lock_wait_timeout))
     DBUG_RETURN(TRUE);
 
-  tdc_remove_table(thd, remove_type,
+  tdc_remove_table(thd, TDC_RT_REMOVE_NOT_OWN,
                    table->s->db.str, table->s->table_name.str,
                    FALSE);
   /* extra() call must come only after all instances above are closed */
@@ -2987,8 +2986,7 @@ bool open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
   }
 
   mysql_mutex_lock(&LOCK_open);
-  if (!(flags & MYSQL_OPEN_IGNORE_FLUSH) ||
-      (share->protected_against_usage() && !(flags & MYSQL_OPEN_FOR_REPAIR)))
+  if (!(flags & MYSQL_OPEN_IGNORE_FLUSH))
   {
     if (share->has_old_version())
     {
@@ -9584,8 +9582,7 @@ void tdc_remove_table(THD *thd, enum_tdc_remove_table_type remove_type,
       {
         DBUG_ASSERT(share->used_tables.is_empty());
       }
-      else if (remove_type == TDC_RT_REMOVE_NOT_OWN ||
-               remove_type == TDC_RT_REMOVE_NOT_OWN_AND_MARK_NOT_USABLE)
+      else if (remove_type == TDC_RT_REMOVE_NOT_OWN)
       {
         TABLE_SHARE::TABLE_list::Iterator it2(share->used_tables);
         while ((table= it2++))
@@ -9598,8 +9595,8 @@ void tdc_remove_table(THD *thd, enum_tdc_remove_table_type remove_type,
       }
 #endif
       /*
-        Mark share to ensure that it gets automatically deleted once
-        it is no longer referenced.
+        Set share's version to zero in order to ensure that it gets
+        automatically deleted once it is no longer referenced.
 
         Note that code in TABLE_SHARE::wait_for_old_version() assumes
         that marking share as old and removal of its unused tables
@@ -9608,13 +9605,8 @@ void tdc_remove_table(THD *thd, enum_tdc_remove_table_type remove_type,
         TDC does not contain old shares which don't have any tables
         used.
       */
-      if (remove_type == TDC_RT_REMOVE_NOT_OWN)
-        share->remove_from_cache_at_close();
-      else if (remove_type != TDC_RT_REMOVE_NOT_OWN_KEEP_SHARE)
-      {
-        /* Ensure that no can open the table while it's used */
-        share->protect_against_usage();
-      }
+      if (remove_type != TDC_RT_REMOVE_NOT_OWN_KEEP_SHARE)
+        share->version= 0;
 
       while ((table= it++))
         free_cache_entry(table);

sql/sql_base.h

@@ -61,7 +61,6 @@ enum find_item_error_report_type {REPORT_ALL_ERRORS, REPORT_EXCEPT_NOT_FOUND,
 
 enum enum_tdc_remove_table_type {TDC_RT_REMOVE_ALL, TDC_RT_REMOVE_NOT_OWN,
                                  TDC_RT_REMOVE_UNUSED,
-                                 TDC_RT_REMOVE_NOT_OWN_AND_MARK_NOT_USABLE,
                                  TDC_RT_REMOVE_NOT_OWN_KEEP_SHARE};
 
 /* bits for last argument to remove_table_from_cache() */
@@ -187,7 +186,6 @@ TABLE *open_ltable(THD *thd, TABLE_LIST *table_list, thr_lock_type update,
 */
 #define MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK         0x1000
 #define MYSQL_LOCK_NOT_TEMPORARY		0x2000
-#define MYSQL_OPEN_FOR_REPAIR                   0x4000
 /**
   Only check THD::killed if waits happen (e.g. wait on MDL, wait on
   table flush, wait on thr_lock.c locks) while opening and locking table.
@@ -297,9 +295,7 @@ bool setup_tables_and_check_access(THD *thd,
                                    ulong want_access,
                                    bool full_table_list);
 bool wait_while_table_is_used(THD *thd, TABLE *table,
-                              enum ha_extra_function function,
-                              enum_tdc_remove_table_type remove_type=
-                              TDC_RT_REMOVE_NOT_OWN);
+                              enum ha_extra_function function);
 
 void drop_open_table(THD *thd, TABLE *table, const char *db_name,
                      const char *table_name);

sql/sql_table.cc

@@ -2446,8 +2446,7 @@ int mysql_rm_table_no_locks(THD *thd, TABLE_LIST *tables, bool if_exists,
 
       if (thd->locked_tables_mode)
       {
-        if (wait_while_table_is_used(thd, table->table, HA_EXTRA_NOT_USED,
-                                     TDC_RT_REMOVE_NOT_OWN_AND_MARK_NOT_USABLE))
+        if (wait_while_table_is_used(thd, table->table, HA_EXTRA_NOT_USED))
         {
           error= -1;
           goto err;

sql/sql_truncate.cc

@@ -369,8 +369,7 @@ bool Sql_cmd_truncate_table::lock_table(THD *thd, TABLE_LIST *table_ref,
   {
     DEBUG_SYNC(thd, "upgrade_lock_for_truncate");
     /* To remove the table from the cache we need an exclusive lock. */
-    if (wait_while_table_is_used(thd, table, HA_EXTRA_PREPARE_FOR_DROP,
-                                 TDC_RT_REMOVE_NOT_OWN_AND_MARK_NOT_USABLE))
+    if (wait_while_table_is_used(thd, table, HA_EXTRA_PREPARE_FOR_DROP))
       DBUG_RETURN(TRUE);
     m_ticket_downgrade= table->mdl_ticket;
     /* Close if table is going to be recreated. */

sql/table.cc

@@ -318,7 +318,7 @@ TABLE_SHARE *alloc_table_share(const char *db, const char *table_name,
     /* TEMPORARY FIX: if true, this means this is mysql.gtid_slave_pos table */
     share->is_gtid_slave_pos= FALSE;
     share->table_category= get_table_category(& share->db, & share->table_name);
-    share->set_refresh_version();
+    share->version= refresh_version;
     share->open_errno= ENOENT;
 
     /*

sql/table.h

@@ -837,36 +837,6 @@ struct TABLE_SHARE
   {
     return version != refresh_version;
   }
-  inline bool protected_against_usage() const
-  {
-    return version == 0;
-  }
-  inline void protect_against_usage()
-  {
-    version= 0;
-  }
-  /*
-    This is used only for the case of locked tables, as we want to
-    allow one to do SHOW commands on them even after ALTER or REPAIR
-  */
-  inline void allow_access_to_protected_table()
-  {
-    DBUG_ASSERT(version == 0);
-    version= 1;
-  }
-  /*
-    Remove from table definition cache at close.
-    Table can still be opened by SHOW
-  */
-  inline void remove_from_cache_at_close()
-  {
-    if (version != 0)                           /* Don't remove protection */
-      version= 1;
-  }
-  inline void set_refresh_version()
-  {
-    version= refresh_version;
-  }
 
   /**
     Convert unrelated members of TABLE_SHARE to one enum