MDEV-11927 InnoDB change buffer is not being merged

to tables in the system tablespace

This is a regression caused by MDEV-11585, which accidentally
changed Tablespace::is_undo_tablespace() in an incorrect way,
causing the InnoDB system tablespace to be reported as a dedicated
undo tablespace, for which the change buffer is not applicable.

Tablespace::is_undo_tablespace(): Remove. There were only 2
calls from the function buf_page_io_complete(). Replace those
calls as appropriate.

Also, merge changes to tablespace import/export tests from
MySQL 5.7, and clean up the tests a little further, allowing
them to be run with any innodb_page_size.

Remove duplicated error injection instrumentation for the
import/export tests.  In MySQL 5.7, the error injection label
buf_page_is_corrupt_failure was renamed to
buf_page_import_corrupt_failure.

fil_space_extend_must_retry(): Correct a debug assertion
(tablespaces can be extended during IMPORT), and remove a
TODO comment about compressed temporary tables that was
already addressed in MDEV-11816.

dict_build_tablespace_for_table(): Correct a comment that
no longer holds after MDEV-11816, and assert that
ROW_FORMAT=COMPRESSED can only be used in .ibd files.

mysql-test/suite/galera/disabled.def

@@ -42,5 +42,3 @@ galera_sst_xtrabackup-v2 : MDEV-11208
 galera_sst_xtrabackup-v2_encrypt_with_key : MDEV-11208
 mysql-wsrep#33 : TODO: investigate
 galera_var_innodb_disallow_writes : MDEV-10949
-galera_many_tables_pk : MDEV-11927
-galera_many_tables_nopk : MDEV-11927

mysql-test/suite/innodb/r/innodb-wl5522.result

@@ -1,4 +1,5 @@
 call mtr.add_suppression("InnoDB: Unable to import tablespace .* because it already exists.  Please DISCARD the tablespace before IMPORT.");
+call mtr.add_suppression("Index for table 't2' is corrupt; try to repair it");
 FLUSH TABLES;
 CREATE TABLE t1
 (a INT AUTO_INCREMENT PRIMARY KEY,
@@ -29,15 +30,19 @@ a	b	c
 823	Evolution	lsjndofiabsoibeg
 822	Devotion	asdfuihknaskdf
 821	Cavalry	..asdasdfaeraf
+CREATE TABLE t2(a INT PRIMARY KEY) ENGINE=InnoDB ROW_FORMAT=COMPACT;
 t1.frm
 t1.ibd
-# Restarting server
-# Done restarting server
-FLUSH TABLE t1 FOR EXPORT;
+t2.frm
+t2.ibd
+FLUSH TABLE t1, t2 FOR EXPORT;
 # List before copying files
 t1.cfg
 t1.frm
 t1.ibd
+t2.cfg
+t2.frm
+t2.ibd
 UNLOCK TABLES;
 INSERT INTO t1 (b, c) SELECT b,c FROM t1 ORDER BY a;
 SELECT COUNT(*) FROM t1;
@@ -58,9 +63,13 @@ a	b	c
 # List before t1 DISCARD
 t1.frm
 t1.ibd
+t2.frm
+t2.ibd
 ALTER TABLE t1 DISCARD TABLESPACE;
 # List after t1 DISCARD
 t1.frm
+t2.frm
+t2.ibd
 ALTER TABLE t1 IMPORT TABLESPACE;
 ALTER TABLE t1 ENGINE InnoDB;
 SELECT COUNT(*) FROM t1;
@@ -79,6 +88,8 @@ a	b	c
 t1.cfg
 t1.frm
 t1.ibd
+t2.frm
+t2.ibd
 SELECT COUNT(*) FROM t1;
 COUNT(*)
 640
@@ -93,6 +104,19 @@ a	b	c
 822	Devotion	asdfuihknaskdf
 821	Cavalry	..asdasdfaeraf
 DROP TABLE t1;
+ALTER TABLE t2 ROW_FORMAT=DYNAMIC;
+ALTER TABLE t2 DISCARD TABLESPACE;
+# List after t2 DISCARD
+t2.frm
+ALTER TABLE t2 IMPORT TABLESPACE;
+ERROR HY000: Schema mismatch (Table flags don't match, server table has 0x4 and the meta-data file has 0x1)
+ALTER TABLE t2 IMPORT TABLESPACE;
+ERROR HY000: Schema mismatch (Expected FSP_SPACE_FLAGS=0x*, .ibd file contains 0x*.)
+DROP TABLE t2;
+SET GLOBAL innodb_file_per_table = 1;
+SELECT @@innodb_file_per_table;
+@@innodb_file_per_table
+1
 CREATE TABLE t1(
 c1 INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
 c2 INT) ENGINE=InnoDB;