Fix a merge error in commit 8f643e20

A merge error caused InnoDB bootstrap to fail when
innodb_undo_tablespaces was set to more than 2.
This was because of a bug that was introduced to
srv_undo_tablespaces_init() by the merge.

Furthermore, some adjustments for Oracle Bug#25551311 aka
Bug#23517560 changes were forgotten. We must minimize direct
references to srv_undo_tablespaces_open and use predicates
instead.

srv_undo_tablespaces_init(): Increment srv_undo_tablespaces_open
once, not twice, per loop iteration.

is_system_or_undo_tablespace(): Remove (unused function).

is_predefined_tablespace(): Invoke srv_is_undo_tablespace().

storage/innobase/buf/buf0buf.cc

@@ -5959,9 +5959,8 @@ buf_page_io_complete(buf_page_t* bpage, bool evict)
 			error injection */
 			DBUG_EXECUTE_IF(
 				"buf_page_import_corrupt_failure",
-				if (bpage->id.space()
-				    > srv_undo_tablespaces_open
-				    && bpage->id.space() != SRV_TMP_SPACE_ID) {
+				if (!is_predefined_tablespace(
+					    bpage->id.space())) {
 					buf_mark_space_corrupt(bpage);
 					ib::info() << "Simulated IMPORT "
 						"corruption";
@@ -6027,8 +6026,7 @@ buf_page_io_complete(buf_page_t* bpage, bool evict)
 		if (uncompressed
 		    && !recv_no_ibuf_operations
 		    && (bpage->id.space() == 0
-			|| (bpage->id.space() > srv_undo_tablespaces_open
-			    && bpage->id.space() != SRV_TMP_SPACE_ID))
+			|| !is_predefined_tablespace(bpage->id.space()))
 		    && !srv_is_tablespace_truncated(bpage->id.space())
 		    && fil_page_get_type(frame) == FIL_PAGE_INDEX
 		    && page_is_leaf(frame)) {

storage/innobase/include/fsp0sysspace.h

@@ -287,16 +287,6 @@ is_system_tablespace(ulint	id)
 	return(id == TRX_SYS_SPACE || id == SRV_TMP_SPACE_ID);
 }
 
-/** Check if shared-system or undo tablespace.
-@return true if shared-system or undo tablespace */
-UNIV_INLINE
-bool
-is_system_or_undo_tablespace(
-	ulint   id)
-{
-	return(id <= srv_undo_tablespaces_open);
-}
-
 /** Check if predefined shared tablespace.
 @return true if predefined shared tablespace */
 UNIV_INLINE
@@ -306,7 +296,8 @@ is_predefined_tablespace(
 {
 	ut_ad(srv_sys_space.space_id() == TRX_SYS_SPACE);
 	ut_ad(TRX_SYS_SPACE == 0);
-	return(id <= srv_undo_tablespaces_open
-	       || id == SRV_TMP_SPACE_ID);
+	return(id == TRX_SYS_SPACE
+	       || id == SRV_TMP_SPACE_ID
+	       || srv_is_undo_tablespace(id));
 }
 #endif /* fsp0sysspace_h */

storage/innobase/include/srv0srv.h

@@ -317,6 +317,22 @@ segment). It is quite possible that some of the tablespaces doesn't host
 any of the rollback-segment based on configuration used. */
 extern ulint	srv_undo_tablespaces_active;
 
+/** Undo tablespaces starts with space_id. */
+extern	ulint	srv_undo_space_id_start;
+
+/** Check whether given space id is undo tablespace id
+@param[in]	space_id	space id to check
+@return true if it is undo tablespace else false. */
+inline
+bool
+srv_is_undo_tablespace(ulint space_id)
+{
+	return srv_undo_space_id_start > 0
+		&& space_id >= srv_undo_space_id_start
+		&& space_id < (srv_undo_space_id_start
+			       + srv_undo_tablespaces_open);
+}
+
 /** The number of undo segments to use */
 extern ulong	srv_undo_logs;
 

storage/innobase/include/srv0start.h

@@ -105,22 +105,6 @@ extern	bool	srv_startup_is_before_trx_rollback_phase;
 /** TRUE if a raw partition is in use */
 extern	ibool	srv_start_raw_disk_in_use;
 
-/** Undo tablespaces starts with space_id. */
-extern	ulint	srv_undo_space_id_start;
-
-/** Check whether given space id is undo tablespace id
-@param[in]	space_id	space id to check
-@return true if it is undo tablespace else false. */
-inline
-bool
-srv_is_undo_tablespace(ulint space_id)
-{
-	return srv_undo_space_id_start > 0
-		&& space_id >= srv_undo_space_id_start
-		&& space_id < (srv_undo_space_id_start
-			       + srv_undo_tablespaces_open);
-}
-
 /** Shutdown state */
 enum srv_shutdown_t {
 	SRV_SHUTDOWN_NONE = 0,	/*!< Database running normally */

storage/innobase/mtr/mtr0mtr.cc

@@ -829,7 +829,7 @@ mtr_t::Command::prepare_write()
 
 	fil_space_t*	space = m_impl->m_user_space;
 
-	if (space != NULL && space->id <= srv_undo_tablespaces_open) {
+	if (space != NULL && is_predefined_tablespace(space->id)) {
 		/* Omit MLOG_FILE_NAME for predefined tablespaces. */
 		space = NULL;
 	}

storage/innobase/srv/srv0start.cc

@@ -959,8 +959,6 @@ srv_undo_tablespaces_init(bool create_new_db)
 		if (0 == srv_undo_tablespaces_open++) {
 			srv_undo_space_id_start = undo_tablespace_ids[i];
 		}
-
-		++srv_undo_tablespaces_open;
 	}
 
 	/* Open any extra unused undo tablespaces. These must be contiguous.