MDEV-14086 Setting innodb_buffer_pool_load_now or innodb_buffer_load_abort...

MDEV-14086 Setting innodb_buffer_pool_load_now or innodb_buffer_load_abort will crash if innodb_read_only

When MySQL 5.6.10 introduced innodb_read_only mode, it skipped the
creation of the InnoDB buffer pool dump/restore subsystem in that mode.
Attempts to set the variable innodb_buf_pool_dump_now would have
no effect in innodb_read_only mode, but the corresponding condition
was forgotten in from the other two update functions.

MySQL 5.7.20 would fix the innodb_buffer_pool_load_now,
but not innodb_buffer_pool_load_abort. Let us fix both in MariaDB.

mysql-test/suite/innodb/r/innodb-get-fk.result

@@ -40,6 +40,9 @@ crew_role_assigned	CREATE TABLE `crew_role_assigned` (
   CONSTRAINT `fk_crewRoleAssigned_crewId` FOREIGN KEY (`crew_id`) REFERENCES `crew` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,
   CONSTRAINT `fk_crewRoleAssigned_pilotId` FOREIGN KEY (`crew_id`) REFERENCES `pilot` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1 COMMENT='This is a comment about tables'
+SET GLOBAL innodb_buffer_pool_load_now = ON;
+SET GLOBAL innodb_buffer_pool_dump_now = ON;
+SET GLOBAL innodb_buffer_pool_load_abort = ON;
 ALTER TABLE `repro`.`crew_role_assigned` COMMENT = "This is a new comment about tables";
 SHOW CREATE TABLE `repro`.`crew_role_assigned`;
 Table	Create Table

mysql-test/suite/innodb/t/innodb-get-fk.test

@@ -40,6 +40,11 @@ CONSTRAINT `fk_crewRoleAssigned_pilotId` FOREIGN KEY (`crew_id`) REFERENCES `rep
 ALTER TABLE `repro`.`crew_role_assigned` COMMENT = 'innodb_read_only';
 SHOW CREATE TABLE `repro`.`crew_role_assigned`;
 
+# These should be ignored in innodb_read_only mode.
+SET GLOBAL innodb_buffer_pool_load_now = ON;
+SET GLOBAL innodb_buffer_pool_dump_now = ON;
+SET GLOBAL innodb_buffer_pool_load_abort = ON;
+
 -- let $restart_parameters=
 -- source include/restart_mysqld.inc
 

storage/innobase/handler/ha_innodb.cc

@@ -16375,7 +16375,7 @@ buffer_pool_load_now(
 	const void*			save)	/*!< in: immediate result from
 						check function */
 {
-	if (*(my_bool*) save) {
+	if (*(my_bool*) save && !srv_read_only_mode) {
 		buf_load_start();
 	}
 }
@@ -16398,7 +16398,7 @@ buffer_pool_load_abort(
 	const void*			save)	/*!< in: immediate result from
 						check function */
 {
-	if (*(my_bool*) save) {
+	if (*(my_bool*) save && !srv_read_only_mode) {
 		buf_load_abort();
 	}
 }

storage/xtradb/handler/ha_innodb.cc

@@ -17651,7 +17651,7 @@ buffer_pool_load_now(
 	const void*			save)	/*!< in: immediate result from
 						check function */
 {
-	if (*(my_bool*) save) {
+	if (*(my_bool*) save && !srv_read_only_mode) {
 		buf_load_start();
 	}
 }
@@ -17674,7 +17674,7 @@ buffer_pool_load_abort(
 	const void*			save)	/*!< in: immediate result from
 						check function */
 {
-	if (*(my_bool*) save) {
+	if (*(my_bool*) save && !srv_read_only_mode) {
 		buf_load_abort();
 	}
 }