Merge 10.1 into 10.2

36 files changed, 358 insertions, 283 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 13d9b1be546..4734c6f7d5f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -187,6 +187,7 @@ ENDIF()
 OPTION(NOT_FOR_DISTRIBUTION "Allow linking with GPLv2-incompatible system libraries. Only set it you never plan to distribute the resulting binaries" OFF)
 
 INCLUDE(check_compiler_flag)
+INCLUDE(check_linker_flag)
 
 OPTION(WITH_ASAN "Enable address sanitizer" OFF)
 IF (WITH_ASAN)
@@ -239,7 +240,7 @@ IF(SECURITY_HARDENED)
   ENDIF()
   # security-enhancing flags
   MY_CHECK_AND_SET_COMPILER_FLAG("-pie -fPIC")
-  MY_CHECK_AND_SET_COMPILER_FLAG("-Wl,-z,relro,-z,now")
+  MY_CHECK_AND_SET_LINKER_FLAG("-Wl,-z,relro,-z,now")
   MY_CHECK_AND_SET_COMPILER_FLAG("-fstack-protector --param=ssp-buffer-size=4")
   MY_CHECK_AND_SET_COMPILER_FLAG("-D_FORTIFY_SOURCE=2" RELEASE RELWITHDEBINFO)
 ENDIF()
diff --git a/cmake/check_linker_flag.cmake b/cmake/check_linker_flag.cmake
new file mode 100644
index 00000000000..ff4b91e89f6
--- /dev/null
+++ b/cmake/check_linker_flag.cmake
@@ -0,0 +1,27 @@
+include(CheckCXXSourceCompiles)
+
+FUNCTION(MY_CHECK_AND_SET_LINKER_FLAG flag_to_set)
+  # Let's avoid expensive compiler tests on Windows:
+  IF(WIN32)
+    RETURN()
+  ENDIF()
+  STRING(REGEX REPLACE "[-,= +]" "_" result "HAVE_LINK_FLAG_${flag_to_set}")
+  SET(SAVE_CMAKE_REQUIRED_LINK_OPTIONS "${CMAKE_REQUIRED_LINK_OPTIONS}")
+  STRING(REGEX REPLACE "^-Wno-" "-W" flag_to_check ${flag_to_set})
+  SET(CMAKE_REQUIRED_LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS} ${flag_to_check})
+  CHECK_CXX_SOURCE_COMPILES("int main(void) { return 0; }" ${result})
+  SET(CMAKE_REQUIRED_LINK_OPTIONS "${SAVE_CMAKE_REQUIRED_LINK_OPTIONS}")
+  IF (${result})
+    FOREACH(linktype SHARED MODULE EXE)
+        IF(ARGN)
+          FOREACH(type ${ARGN})
+            SET(CMAKE_${linktype}_LINKER_FLAGS_${type}
+              "${CMAKE_${linktype}_LINKER_FLAGS_${type}} ${flag_to_set}" PARENT_SCOPE)
+          ENDFOREACH()
+        ELSE()
+          SET(CMAKE_${linktype}_LINKER_FLAGS
+            "${CMAKE_${linktype}_LINKER_FLAGS} ${flag_to_set}" PARENT_SCOPE)
+        ENDIF()
+    ENDFOREACH()
+  ENDIF()
+ENDFUNCTION()
diff --git a/mysql-test/r/stat_tables_innodb.result b/mysql-test/r/stat_tables_innodb.result
index a436efb5fea..23b952cc891 100644
--- a/mysql-test/r/stat_tables_innodb.result
+++ b/mysql-test/r/stat_tables_innodb.result
@@ -855,4 +855,28 @@ drop table t1;
 # please keep this at the last
 set @@global.histogram_size=@save_histogram_size;
 set optimizer_switch=@save_optimizer_switch_for_stat_tables_test;
+#
+# MDEV-22851: Engine independent index statistics are incorrect for large tables on Windows.
+#
+CREATE TABLE t1(a INT) ENGINE=INNODB;
+INSERT INTO t1 SELECT 1 FROM seq_1_to_60000;
+SET @save_use_stat_tables= @@use_stat_tables;
+SET use_stat_tables= preferably;
+SELECT count(*) FROM t1;
+count(*)
+60000
+CREATE INDEX idx ON t1(a);
+ANALYZE TABLE t1 PERSISTENT FOR COLUMNS (a) INDEXES (idx);
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	Engine-independent statistics collected
+test.t1	analyze	status	OK
+SELECT * FROM mysql.index_stats where table_name='t1';
+db_name	table_name	index_name	prefix_arity	avg_frequency
+test	t1	idx	1	60000.0000
+SELECT * FROM mysql.column_stats where table_name='t1';
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency	hist_size	hist_type	histogram
+test	t1	a	1	1	0.0000	4.0000	60000.0000	0	NULL	NULL
+SET use_stat_tables= @save_use_stat_tables;
+DROP TABLE t1;
+# end of 10.1 tests
 SET SESSION STORAGE_ENGINE=DEFAULT;
diff --git a/mysql-test/t/stat_tables_innodb.test b/mysql-test/t/stat_tables_innodb.test
index 04e81de8f9d..008ca6911e9 100644
--- a/mysql-test/t/stat_tables_innodb.test
+++ b/mysql-test/t/stat_tables_innodb.test
@@ -1,4 +1,5 @@
 --source include/have_innodb.inc
+--source include/have_sequence.inc
 
 SET SESSION STORAGE_ENGINE='InnoDB';
 
@@ -9,4 +10,23 @@ set optimizer_switch='extended_keys=on';
 
 set optimizer_switch=@save_optimizer_switch_for_stat_tables_test;
 
+--echo #
+--echo # MDEV-22851: Engine independent index statistics are incorrect for large tables on Windows.
+--echo #
+
+CREATE TABLE t1(a INT) ENGINE=INNODB;
+INSERT INTO t1 SELECT 1 FROM seq_1_to_60000;
+
+SET @save_use_stat_tables= @@use_stat_tables;
+SET use_stat_tables= preferably;
+SELECT count(*) FROM t1;
+CREATE INDEX idx ON t1(a);
+ANALYZE TABLE t1 PERSISTENT FOR COLUMNS (a) INDEXES (idx);
+SELECT * FROM mysql.index_stats where table_name='t1';
+SELECT * FROM mysql.column_stats where table_name='t1';
+SET use_stat_tables= @save_use_stat_tables;
+DROP TABLE t1;
+
+--echo # end of 10.1 tests
+
 SET SESSION STORAGE_ENGINE=DEFAULT;
diff --git a/sql/sql_statistics.cc b/sql/sql_statistics.cc
index d6ee4f10106..d22921ba1e2 100644
--- a/sql/sql_statistics.cc
+++ b/sql/sql_statistics.cc
@@ -2108,8 +2108,8 @@ int alloc_statistics_for_table(THD* thd, TABLE *table)
                                     sizeof(Index_statistics) * keys);
 
   uint key_parts= table->s->ext_key_parts;
-  ulong *idx_avg_frequency= (ulong*) alloc_root(&table->mem_root,
-                                                sizeof(ulong) * key_parts);
+  ulonglong *idx_avg_frequency= (ulonglong*) alloc_root(&table->mem_root,
+                                               sizeof(ulonglong) * key_parts);
 
   uint columns= 0;
   for (field_ptr= table->field; *field_ptr; field_ptr++)
@@ -2154,7 +2154,7 @@ int alloc_statistics_for_table(THD* thd, TABLE *table)
     }
   }
 
-  memset(idx_avg_frequency, 0, sizeof(ulong) * key_parts);
+  memset(idx_avg_frequency, 0, sizeof(ulonglong) * key_parts);
 
   KEY *key_info, *end;
   for (key_info= table->key_info, end= key_info + table->s->keys;
@@ -2270,14 +2270,14 @@ static int alloc_statistics_for_table_share(THD* thd, TABLE_SHARE *table_share)
   }
 
   uint key_parts= table_share->ext_key_parts;
-  ulong *idx_avg_frequency=  table_stats->idx_avg_frequency;
+  ulonglong *idx_avg_frequency=  table_stats->idx_avg_frequency;
   if (!idx_avg_frequency)
   {
-    idx_avg_frequency= (ulong*) alloc_root(&stats_cb->mem_root,
-                                           sizeof(ulong) * key_parts);
+    idx_avg_frequency= (ulonglong*) alloc_root(&stats_cb->mem_root,
+                                               sizeof(ulonglong) * key_parts);
     if (idx_avg_frequency)
     {
-      memset(idx_avg_frequency, 0, sizeof(ulong) * key_parts);
+      memset(idx_avg_frequency, 0, sizeof(ulonglong) * key_parts);
       table_stats->idx_avg_frequency= idx_avg_frequency;
       for (key_info= table_share->key_info, end= key_info + keys;
            key_info < end; 
diff --git a/sql/sql_statistics.h b/sql/sql_statistics.h
index 145c207af58..fa3e8d6b894 100644
--- a/sql/sql_statistics.h
+++ b/sql/sql_statistics.h
@@ -279,7 +279,9 @@ public:
   uchar *min_max_record_buffers;    /* Record buffers for min/max values  */
   Column_statistics *column_stats;  /* Array of statistical data for columns */
   Index_statistics *index_stats;    /* Array of statistical data for indexes */
-  ulong *idx_avg_frequency;   /* Array of records per key for index prefixes */
+
+  /* Array of records per key for index prefixes */
+  ulonglong *idx_avg_frequency;
   uchar *histograms;                /* Sequence of histograms       */                    
 };
 
@@ -331,7 +333,7 @@ private:
     CHAR values are stripped of trailing spaces.
     Flexible values are stripped of their length prefixes.
   */
-  ulong avg_length;
+  ulonglong avg_length;
 
   /*
     The ratio N/D multiplied by the scale factor Scale_factor_avg_frequency,
@@ -339,7 +341,7 @@ private:
        N is the number of rows with not null value in the column,
        D the number of distinct values among them
   */
-  ulong avg_frequency;
+  ulonglong avg_frequency;
 
 public:
 
@@ -389,12 +391,12 @@ public:
 
   void set_avg_length (double val)
   {
-    avg_length= (ulong) (val * Scale_factor_avg_length);
+    avg_length= (ulonglong) (val * Scale_factor_avg_length);
   }
 
   void set_avg_frequency (double val)
   {
-    avg_frequency= (ulong) (val * Scale_factor_avg_frequency);
+    avg_frequency= (ulonglong) (val * Scale_factor_avg_frequency);
   }
 
   bool min_max_values_are_provided()
@@ -433,11 +435,11 @@ private:
     in the first k components, and D is the number of distinct
     k-component prefixes among them 
   */
-  ulong *avg_frequency;
+  ulonglong *avg_frequency;
 
 public:
 
-  void init_avg_frequency(ulong *ptr) { avg_frequency= ptr; }
+  void init_avg_frequency(ulonglong *ptr) { avg_frequency= ptr; }
 
   bool avg_frequency_is_inited() { return avg_frequency != NULL; }
 
@@ -448,7 +450,7 @@ public:
 
   void set_avg_frequency(uint i, double val)
   {
-    avg_frequency[i]= (ulong) (val * Scale_factor_avg_frequency);
+    avg_frequency[i]= (ulonglong) (val * Scale_factor_avg_frequency);
   }
 
 };
diff --git a/storage/innobase/buf/buf0dblwr.cc b/storage/innobase/buf/buf0dblwr.cc
index 7148a6fbfd0..6cc4bd6dc00 100644
--- a/storage/innobase/buf/buf0dblwr.cc
+++ b/storage/innobase/buf/buf0dblwr.cc
@@ -566,7 +566,7 @@ buf_dblwr_process()
 		const ulint		page_no	= page_get_page_no(page);
 		const page_id_t		page_id(space_id, page_no);
 
-		if (page_no >= space->size) {
+		if (UNIV_UNLIKELY(page_no >= space->size)) {
 
 			/* Do not report the warning if the tablespace
 			is scheduled for truncation or was truncated
@@ -574,10 +574,12 @@ buf_dblwr_process()
 			if (!srv_is_tablespace_truncated(space_id)
 			    && !srv_was_tablespace_truncated(space)
 			    && !srv_is_undo_tablespace(space_id)) {
-				ib::warn() << "A copy of page " << page_id
+				ib::warn() << "A copy of page " << page_no
 					<< " in the doublewrite buffer slot "
 					<< page_no_dblwr
-					<< " is not within space bounds";
+					<< " is beyond the end of tablespace "
+					<< space->name
+					<< " (" << space->size << " pages)";
 			}
 			continue;
 		}
diff --git a/storage/innobase/buf/buf0flu.cc b/storage/innobase/buf/buf0flu.cc
index 9b395bd3231..26610337d0d 100644
--- a/storage/innobase/buf/buf0flu.cc
+++ b/storage/innobase/buf/buf0flu.cc
@@ -1391,9 +1391,11 @@ buf_flush_try_neighbors(
 		}
 	}
 
-	const ulint	space_size = fil_space_get_size(page_id.space());
-	if (high > space_size) {
-		high = space_size;
+	if (fil_space_t *s = fil_space_acquire_for_io(page_id.space())) {
+		high = s->max_page_number_for_io(high);
+		fil_space_release_for_io(s);
+	} else {
+		return 0;
 	}
 
 	DBUG_PRINT("ib_buf", ("flush %u:%u..%u",
diff --git a/storage/innobase/buf/buf0rea.cc b/storage/innobase/buf/buf0rea.cc
index 43831dedb2c..d6f096fc80e 100644
--- a/storage/innobase/buf/buf0rea.cc
+++ b/storage/innobase/buf/buf0rea.cc
@@ -279,11 +279,7 @@ buf_read_ahead_random(
 	high = (page_id.page_no() / buf_read_ahead_random_area + 1)
 		* buf_read_ahead_random_area;
 
-	/* Remember the tablespace version before we ask the tablespace size
-	below: if DISCARD + IMPORT changes the actual .ibd file meanwhile, we
-	do not try to read outside the bounds of the tablespace! */
 	if (fil_space_t* space = fil_space_acquire(page_id.space())) {
-
 #ifdef UNIV_DEBUG
 		if (srv_file_per_table) {
 			ulint	size = 0;
@@ -301,9 +297,7 @@ buf_read_ahead_random(
 		}
 #endif /* UNIV_DEBUG */
 
-		if (high > space->size) {
-			high = space->size;
-		}
+		high = space->max_page_number_for_io(high);
 		fil_space_release(space);
 	} else {
 		return(0);
@@ -580,13 +574,10 @@ buf_read_ahead_linear(
 		return(0);
 	}
 
-	/* Remember the tablespace version before we ask te tablespace size
-	below: if DISCARD + IMPORT changes the actual .ibd file meanwhile, we
-	do not try to read outside the bounds of the tablespace! */
 	ulint	space_size;
 
 	if (fil_space_t* space = fil_space_acquire(page_id.space())) {
-		space_size = space->size;
+		space_size = space->committed_size;
 		fil_space_release(space);
 
 		if (high > space_size) {
diff --git a/storage/innobase/fil/fil0fil.cc b/storage/innobase/fil/fil0fil.cc
index 42f7a7fc3c9..f9d7070a41b 100644
--- a/storage/innobase/fil/fil0fil.cc
+++ b/storage/innobase/fil/fil0fil.cc
@@ -359,34 +359,6 @@ fil_space_get(
 	return(space);
 }
 
-/** Returns the latch of a file space.
-@param[in]	id	space id
-@param[out]	flags	tablespace flags
-@return latch protecting storage allocation */
-rw_lock_t*
-fil_space_get_latch(
-	ulint	id,
-	ulint*	flags)
-{
-	fil_space_t*	space;
-
-	ut_ad(fil_system);
-
-	mutex_enter(&fil_system->mutex);
-
-	space = fil_space_get_by_id(id);
-
-	ut_a(space);
-
-	if (flags) {
-		*flags = space->flags;
-	}
-
-	mutex_exit(&fil_system->mutex);
-
-	return(&(space->latch));
-}
-
 /** Gets the type of a file space.
 @param[in]	id	tablespace identifier
 @return file type */
@@ -593,13 +565,17 @@ bool fil_node_t::read_page0(bool first)
 		}
 
 		this->size = ulint(size_bytes / psize);
-		space->size += this->size;
+		space->committed_size = space->size += this->size;
 	} else if (space->id != TRX_SYS_SPACE || space->size_in_header) {
 		/* If this is not the first-time open, do nothing.
 		For the system tablespace, we always get invoked as
 		first=false, so we detect the true first-time-open based
-		on size_in_header and proceed to initiailze the data. */
+		on size_in_header and proceed to initialize the data. */
 		return true;
+	} else {
+		/* Initialize the size of predefined tablespaces
+		to FSP_SIZE. */
+		space->committed_size = size;
 	}
 
 	ut_ad(space->free_limit == 0 || space->free_limit == free_limit);
@@ -1126,6 +1102,9 @@ fil_mutex_enter_and_prepare_for_io(
 			ut_a(success);
 			/* InnoDB data files cannot shrink. */
 			ut_a(space->size >= size);
+			if (size > space->committed_size) {
+				space->committed_size = size;
+			}
 
 			/* There could be multiple concurrent I/O requests for
 			this tablespace (multiple threads trying to extend
diff --git a/storage/innobase/fsp/fsp0fsp.cc b/storage/innobase/fsp/fsp0fsp.cc
index 2501f4f8ba3..8a393b15952 100644
--- a/storage/innobase/fsp/fsp0fsp.cc
+++ b/storage/innobase/fsp/fsp0fsp.cc
@@ -422,7 +422,7 @@ xdes_get_descriptor_with_space_hdr(
 	ulint	size;
 	ulint	descr_page_no;
 	page_t*	descr_page;
-	ut_ad(mtr_memo_contains(mtr, &space->latch, MTR_MEMO_X_LOCK));
+	ut_ad(mtr_memo_contains(mtr, space, MTR_MEMO_SPACE_X_LOCK));
 	ut_ad(mtr_memo_contains_page(mtr, sp_header, MTR_MEMO_PAGE_SX_FIX));
 	ut_ad(page_offset(sp_header) == FSP_HEADER_OFFSET);
 	/* Read free limit and space size */
@@ -566,7 +566,7 @@ xdes_lst_get_descriptor(
 	fil_addr_t		lst_node,
 	mtr_t*			mtr)
 {
-	ut_ad(mtr_memo_contains(mtr, &space->latch, MTR_MEMO_X_LOCK));
+	ut_ad(mtr_memo_contains(mtr, space, MTR_MEMO_SPACE_X_LOCK));
 	ut_ad(page_size.equals_to(page_size_t(space->flags)));
 	return(fut_get_ptr(space->id, page_size, lst_node, RW_SX_LATCH, mtr)
 	       - XDES_FLST_NODE);
@@ -1112,42 +1112,22 @@ fsp_fill_free_list(
 						 MLOG_2BYTES, mtr);
 			}
 
-			/* Initialize the ibuf bitmap page in a separate
-			mini-transaction because it is low in the latching
-			order, and we must be able to release its latch.
-			Note: Insert-Buffering is disabled for tables that
-			reside in the temp-tablespace. */
 			if (space->purpose != FIL_TYPE_TEMPORARY) {
-				mtr_t	ibuf_mtr;
-
-				mtr_start(&ibuf_mtr);
-				ibuf_mtr.set_named_space(space);
-
-				/* Avoid logging while truncate table
-				fix-up is active. */
-				if (srv_is_tablespace_truncated(space->id)) {
-					mtr_set_log_mode(
-						&ibuf_mtr, MTR_LOG_NO_REDO);
-				}
-
 				const page_id_t	page_id(
 					space->id,
 					i + FSP_IBUF_BITMAP_OFFSET);
 
 				block = buf_page_create(
-					page_id, page_size, &ibuf_mtr);
+					page_id, page_size, mtr);
 
 				buf_page_get(
-					page_id, page_size, RW_SX_LATCH,
-					&ibuf_mtr);
+					page_id, page_size, RW_SX_LATCH, mtr);
 
 				buf_block_dbg_add_level(block, SYNC_FSP_PAGE);
 
-				fsp_init_file_page(space, block, &ibuf_mtr);
-
-				ibuf_bitmap_page_init(block, &ibuf_mtr);
+				fsp_init_file_page(space, block, mtr);
 
-				mtr_commit(&ibuf_mtr);
+				ibuf_bitmap_page_init(block, mtr);
 			}
 		}
 
@@ -1569,7 +1549,7 @@ fsp_free_extent(
 	fsp_header_t*	header;
 	xdes_t*		descr;
 
-	ut_ad(mtr_memo_contains(mtr, &space->latch, MTR_MEMO_X_LOCK));
+	ut_ad(mtr_memo_contains(mtr, space, MTR_MEMO_SPACE_X_LOCK));
 
 	header = fsp_get_space_header(space, page_size, mtr);
 
diff --git a/storage/innobase/ibuf/ibuf0ibuf.cc b/storage/innobase/ibuf/ibuf0ibuf.cc
index 2eea443a434..7e01c864a50 100644
--- a/storage/innobase/ibuf/ibuf0ibuf.cc
+++ b/storage/innobase/ibuf/ibuf0ibuf.cc
@@ -1984,7 +1984,7 @@ ibuf_add_free_page(void)
 
 	/* Acquire the fsp latch before the ibuf header, obeying the latching
 	order */
-	mtr_x_lock(&space->latch, &mtr);
+	mtr.x_lock_space(space, __FILE__, __LINE__);
 	header_page = ibuf_header_page_get(&mtr);
 
 	/* Allocate a new page: NOTE that if the page has been a part of a
@@ -2068,7 +2068,7 @@ ibuf_remove_free_page(void)
 	/* Acquire the fsp latch before the ibuf header, obeying the latching
 	order */
 
-	mtr_x_lock(&space->latch, &mtr);
+	mtr.x_lock_space(space, __FILE__, __LINE__);
 	header_page = ibuf_header_page_get(&mtr);
 
 	/* Prevent pessimistic inserts to insert buffer trees for a while */
diff --git a/storage/innobase/include/fil0fil.h b/storage/innobase/include/fil0fil.h
index 62d87ce2c06..585a284798e 100644
--- a/storage/innobase/include/fil0fil.h
+++ b/storage/innobase/include/fil0fil.h
@@ -135,6 +135,8 @@ struct fil_space_t : ilist_node<unflushed_spaces_tag_t>,
 				/*!< recovered tablespace size in pages;
 				0 if no size change was read from the redo log,
 				or if the size change was implemented */
+  /** the committed size of the tablespace in pages */
+  ulint committed_size;
 	ulint		flags;	/*!< FSP_SPACE_FLAGS and FSP_FLAGS_MEM_ flags;
 				see fsp0types.h,
 				fsp_flags_is_valid(),
@@ -193,6 +195,15 @@ struct fil_space_t : ilist_node<unflushed_spaces_tag_t>,
 	/** @return whether the tablespace is about to be dropped */
 	bool is_stopping() const { return stop_new_ops;	}
 
+  /** Clamp a page number for batched I/O, such as read-ahead.
+  @param offset   page number limit
+  @return offset clamped to the tablespace size */
+  ulint max_page_number_for_io(ulint offset) const
+  {
+    const ulint limit= committed_size;
+    return limit > offset ? offset : limit;
+  }
+
 	/** @return whether doublewrite buffering is needed */
 	bool use_doublewrite() const
 	{
@@ -571,15 +582,6 @@ extern fil_system_t*	fil_system;
 
 #include "fil0crypt.h"
 
-/** Returns the latch of a file space.
-@param[in]	id	space id
-@param[out]	flags	tablespace flags
-@return latch protecting storage allocation */
-rw_lock_t*
-fil_space_get_latch(
-	ulint	id,
-	ulint*	flags);
-
 /** Gets the type of a file space.
 @param[in]	id	tablespace identifier
 @return file type */
diff --git a/storage/innobase/include/mtr0mtr.h b/storage/innobase/include/mtr0mtr.h
index 30d2e937f1f..e91590d48d1 100644
--- a/storage/innobase/include/mtr0mtr.h
+++ b/storage/innobase/include/mtr0mtr.h
@@ -2,7 +2,7 @@
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2012, Facebook Inc.
-Copyright (c) 2013, 2019, MariaDB Corporation.
+Copyright (c) 2013, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -302,6 +302,12 @@ struct mtr_t {
 		const char*	file,
 		unsigned	line);
 
+	/** Exclusively aqcuire a tablespace latch.
+	@param space  tablespace
+	@param file   source code file name of the caller
+	@param line   source code line number */
+	void x_lock_space(fil_space_t *space, const char *file, unsigned line);
+
 	/** Release an object in the memo stack.
 	@param object	object
 	@param type	object type: MTR_MEMO_S_LOCK, ...
diff --git a/storage/innobase/include/mtr0mtr.ic b/storage/innobase/include/mtr0mtr.ic
index 7175ede0d6a..8d68affb1cb 100644
--- a/storage/innobase/include/mtr0mtr.ic
+++ b/storage/innobase/include/mtr0mtr.ic
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2014, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2019, MariaDB Corporation.
+Copyright (c) 2017, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -48,7 +48,7 @@ mtr_t::memo_push(void* object, mtr_memo_type_t type)
 	ut_ad(is_active());
 	ut_ad(object != NULL);
 	ut_ad(type >= MTR_MEMO_PAGE_S_FIX);
-	ut_ad(type <= MTR_MEMO_SX_LOCK);
+	ut_ad(type <= MTR_MEMO_SPACE_X_LOCK);
 	ut_ad(ut_is_2pow(type));
 
 	/* If this mtr has x-fixed a clean page then we set
diff --git a/storage/innobase/include/mtr0types.h b/storage/innobase/include/mtr0types.h
index 985ad7b81ea..2d4cd7b97ac 100644
--- a/storage/innobase/include/mtr0types.h
+++ b/storage/innobase/include/mtr0types.h
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2015, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2019, MariaDB Corporation.
+Copyright (c) 2017, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -263,7 +263,10 @@ enum mtr_memo_type_t {
 
 	MTR_MEMO_X_LOCK = RW_X_LATCH << 5,
 
-	MTR_MEMO_SX_LOCK = RW_SX_LATCH << 5
+	MTR_MEMO_SX_LOCK = RW_SX_LATCH << 5,
+
+	/** acquire X-latch on fil_space_t::latch */
+	MTR_MEMO_SPACE_X_LOCK = MTR_MEMO_SX_LOCK << 1
 };
 #endif /* !UNIV_CHECKSUM */
 
diff --git a/storage/innobase/mtr/mtr0mtr.cc b/storage/innobase/mtr/mtr0mtr.cc
index 9fdb10e230c..b649d907c23 100644
--- a/storage/innobase/mtr/mtr0mtr.cc
+++ b/storage/innobase/mtr/mtr0mtr.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2019, MariaDB Corporation.
+Copyright (c) 2017, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -218,6 +218,13 @@ static void memo_slot_release(mtr_memo_slot_t *slot)
   case MTR_MEMO_SX_LOCK:
     rw_lock_sx_unlock(reinterpret_cast<rw_lock_t*>(slot->object));
     break;
+  case MTR_MEMO_SPACE_X_LOCK:
+    {
+      fil_space_t *space= static_cast<fil_space_t*>(slot->object);
+      space->committed_size= space->size;
+      rw_lock_x_unlock(&space->latch);
+    }
+    break;
   case MTR_MEMO_X_LOCK:
     rw_lock_x_unlock(reinterpret_cast<rw_lock_t*>(slot->object));
     break;
@@ -251,6 +258,13 @@ struct ReleaseLatches {
     case MTR_MEMO_S_LOCK:
       rw_lock_s_unlock(reinterpret_cast<rw_lock_t*>(slot->object));
       break;
+    case MTR_MEMO_SPACE_X_LOCK:
+      {
+        fil_space_t *space= static_cast<fil_space_t*>(slot->object);
+        space->committed_size= space->size;
+        rw_lock_x_unlock(&space->latch);
+      }
+      break;
     case MTR_MEMO_X_LOCK:
       rw_lock_x_unlock(reinterpret_cast<rw_lock_t*>(slot->object));
       break;
@@ -564,13 +578,23 @@ mtr_t::x_lock_space(ulint space_id, const char* file, unsigned line)
 
 	ut_ad(space);
 	ut_ad(space->id == space_id);
-	x_lock(&space->latch, file, line);
+	x_lock_space(space, file, line);
 	ut_ad(space->purpose == FIL_TYPE_TEMPORARY
 	      || space->purpose == FIL_TYPE_IMPORT
 	      || space->purpose == FIL_TYPE_TABLESPACE);
 	return(space);
 }
 
+/** Exclusively aqcuire a tablespace latch.
+@param space  tablespace
+@param file   source code file name of the caller
+@param line   source code line number */
+void mtr_t::x_lock_space(fil_space_t *space, const char *file, unsigned line)
+{
+  rw_lock_x_lock_inline(&space->latch, 0, file, line);
+  memo_push(space, MTR_MEMO_SPACE_X_LOCK);
+}
+
 /** Look up the system tablespace. */
 void
 mtr_t::lookup_sys_space()
@@ -764,27 +788,20 @@ with index pages.
 void
 mtr_t::release_free_extents(ulint n_reserved)
 {
-	fil_space_t*	space;
-
-	ut_ad(!m_undo_space);
-
-	if (m_user_space) {
+  fil_space_t *space= m_user_space;
 
-		ut_ad(m_user_space->id == m_user_space_id);
-		ut_ad(memo_contains(get_memo(), &m_user_space->latch,
-				    MTR_MEMO_X_LOCK));
+  ut_ad(!m_undo_space);
 
-		space = m_user_space;
-	} else {
-
-		ut_ad(m_sys_space->id == TRX_SYS_SPACE);
-		ut_ad(memo_contains(get_memo(), &m_sys_space->latch,
-				    MTR_MEMO_X_LOCK));
-
-		space = m_sys_space;
-	}
+  if (space)
+    ut_ad(m_user_space->id == m_user_space_id);
+  else
+  {
+    ut_ad(m_sys_space->id == TRX_SYS_SPACE);
+    space= m_sys_space;
+  }
 
-	space->release_free_extents(n_reserved);
+  ut_ad(memo_contains(get_memo(), space, MTR_MEMO_SPACE_X_LOCK));
+  space->release_free_extents(n_reserved);
 }
 
 #ifdef UNIV_DEBUG
diff --git a/storage/innobase/row/row0import.cc b/storage/innobase/row/row0import.cc
index ed78b2a154d..981c5046de1 100644
--- a/storage/innobase/row/row0import.cc
+++ b/storage/innobase/row/row0import.cc
@@ -527,14 +527,6 @@ protected:
 	/** Space id of the file being iterated over. */
 	ulint			m_space;
 
-	/** Minimum page number for which the free list has not been
-	initialized: the pages >= this limit are, by definition, free;
-	note that in a single-table tablespace where size < 64 pages,
-	this number is 64, i.e., we have initialized the space about
-	the first extent, but have not physically allocted those pages
-	to the file. @see FSP_LIMIT. */
-	ulint			m_free_limit;
-
 	/** Current size of the space in pages */
 	ulint			m_size;
 
@@ -594,7 +586,6 @@ AbstractCallback::init(
 	ut_a(m_space == ULINT_UNDEFINED);
 
 	m_size  = mach_read_from_4(page + FSP_SIZE);
-	m_free_limit = mach_read_from_4(page + FSP_FREE_LIMIT);
 	m_space = mach_read_from_4(page + FSP_HEADER_OFFSET + FSP_SPACE_ID);
 
 	return set_current_xdes(0, page);
diff --git a/storage/innobase/srv/srv0start.cc b/storage/innobase/srv/srv0start.cc
index 8479847f779..0d8ebbe98cd 100644
--- a/storage/innobase/srv/srv0start.cc
+++ b/storage/innobase/srv/srv0start.cc
@@ -3,7 +3,7 @@
 Copyright (c) 1996, 2017, Oracle and/or its affiliates. All rights reserved.
 Copyright (c) 2008, Google Inc.
 Copyright (c) 2009, Percona Inc.
-Copyright (c) 2013, 2019, MariaDB Corporation.
+Copyright (c) 2013, 2020, MariaDB Corporation.
 
 Portions of this file contain modifications contributed and copyrighted by
 Google, Inc. Those modifications are gratefully acknowledged and are described
@@ -696,6 +696,7 @@ static bool srv_undo_tablespace_open(const char* name, ulint space_id,
 	if (create_new_db) {
 		space->size = file->size = ulint(size >> srv_page_size_shift);
 		space->size_in_header = SRV_UNDO_TABLESPACE_SIZE_IN_PAGES;
+		space->committed_size = SRV_UNDO_TABLESPACE_SIZE_IN_PAGES;
 	} else {
 		success = file->read_page0(true);
 		if (!success) {
@@ -1044,7 +1045,7 @@ srv_undo_tablespaces_init(bool create_new_db)
 			fsp_header_init(
 				*it, SRV_UNDO_TABLESPACE_SIZE_IN_PAGES, &mtr);
 
-			mtr_x_lock(fil_space_get_latch(*it, NULL), &mtr);
+			mtr_x_lock_space(*it, &mtr);
 
 			for (ulint i = 0; i < TRX_SYS_N_RSEGS; i++) {
 
diff --git a/storage/innobase/trx/trx0purge.cc b/storage/innobase/trx/trx0purge.cc
index 2f728b22fb2..2025ac70beb 100644
--- a/storage/innobase/trx/trx0purge.cc
+++ b/storage/innobase/trx/trx0purge.cc
@@ -995,7 +995,7 @@ trx_purge_initiate_truncate(
 	mtr_t mtr;
 	const ulint size = SRV_UNDO_TABLESPACE_SIZE_IN_PAGES;
 	mtr.start();
-	mtr_x_lock(&space->latch, &mtr);
+	mtr.x_lock_space(space, __FILE__, __LINE__);
 	fil_truncate_log(space, size, &mtr);
 	fsp_header_init(space_id, size, &mtr);
 	mutex_enter(&fil_system->mutex);
diff --git a/storage/innobase/trx/trx0rseg.cc b/storage/innobase/trx/trx0rseg.cc
index e76695b7e43..60ebfa3c9a8 100644
--- a/storage/innobase/trx/trx0rseg.cc
+++ b/storage/innobase/trx/trx0rseg.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1996, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2019, MariaDB Corporation.
+Copyright (c) 2017, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -53,8 +53,8 @@ trx_rseg_header_create(
 	buf_block_t*	block;
 
 	ut_ad(mtr);
-	ut_ad(mtr_memo_contains(mtr, fil_space_get_latch(space, NULL),
-				MTR_MEMO_X_LOCK));
+	ut_ad(mtr_memo_contains(mtr, fil_space_get(space),
+				MTR_MEMO_SPACE_X_LOCK));
 
 	/* Allocate a new file segment for the rollback segment */
 	block = fseg_create(space, 0, TRX_RSEG + TRX_RSEG_FSEG_HEADER, mtr);
diff --git a/storage/innobase/trx/trx0sys.cc b/storage/innobase/trx/trx0sys.cc
index 415afc4a90b..2225c69b62e 100644
--- a/storage/innobase/trx/trx0sys.cc
+++ b/storage/innobase/trx/trx0sys.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1996, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2019, MariaDB Corporation.
+Copyright (c) 2017, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
diff --git a/storage/xtradb/buf/buf0dblwr.cc b/storage/xtradb/buf/buf0dblwr.cc
index 9f03778e572..a405c3edf5e 100644
--- a/storage/xtradb/buf/buf0dblwr.cc
+++ b/storage/xtradb/buf/buf0dblwr.cc
@@ -554,12 +554,18 @@ buf_dblwr_process()
 			continue;
 		}
 
-		if (!fil_check_adress_in_tablespace(space_id, page_no)) {
+		if (!space()->size) {
+			fil_space_get_size(space_id);
+		}
+
+		if (UNIV_UNLIKELY(space()->size <= page_no)) {
 			ib_logf(IB_LOG_LEVEL_WARN,
-				"A copy of page " ULINTPF ":" ULINTPF
+				"A copy of page " ULINTPF
 				" in the doublewrite buffer slot " ULINTPF
-				" is not within space bounds",
-				space_id, page_no, page_no_dblwr);
+				" is beyond the end of the tablespace "
+				" %s (" ULINTPF " pages)",
+				page_no, page_no_dblwr,
+				space()->name, space()->size);
 			continue;
 		}
 
diff --git a/storage/xtradb/buf/buf0flu.cc b/storage/xtradb/buf/buf0flu.cc
index 9c427395231..2a656d748b1 100644
--- a/storage/xtradb/buf/buf0flu.cc
+++ b/storage/xtradb/buf/buf0flu.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2013, 2019, MariaDB Corporation.
+Copyright (c) 2013, 2020, MariaDB Corporation.
 Copyright (c) 2013, 2014, Fusion-io
 
 This program is free software; you can redistribute it and/or modify it under
@@ -1297,8 +1297,11 @@ buf_flush_try_neighbors(
 
 	/* fprintf(stderr, "Flush area: low %lu high %lu\n", low, high); */
 
-	if (high > fil_space_get_size(space)) {
-		high = fil_space_get_size(space);
+	if (fil_space_t *s = fil_space_acquire_for_io(space)) {
+		high = s->max_page_number_for_io(high);
+		fil_space_release_for_io(s);
+	} else {
+		return 0;
 	}
 
 	ulint	count = 0;
diff --git a/storage/xtradb/buf/buf0rea.cc b/storage/xtradb/buf/buf0rea.cc
index 1ef9162cab9..a962b94c0c2 100644
--- a/storage/xtradb/buf/buf0rea.cc
+++ b/storage/xtradb/buf/buf0rea.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2013, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2013, 2018, MariaDB Corporation.
+Copyright (c) 2013, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -344,19 +344,22 @@ buf_read_ahead_random(
 		return(0);
 	}
 
-	/* Remember the tablespace version before we ask te tablespace size
-	below: if DISCARD + IMPORT changes the actual .ibd file meanwhile, we
-	do not try to read outside the bounds of the tablespace! */
+	if (fil_space_t *s = fil_space_acquire_for_io(space)) {
+		/* Remember the tablespace version along with the
+		tablespace size: if DISCARD + IMPORT changes the
+		actual .ibd file meanwhile, we do not try to read
+		outside the bounds of the tablespace! */
+		tablespace_version = s->tablespace_version;
 
-	tablespace_version = fil_space_get_version(space);
-
-	low  = (offset / buf_read_ahead_random_area)
-		* buf_read_ahead_random_area;
-	high = (offset / buf_read_ahead_random_area + 1)
-		* buf_read_ahead_random_area;
-	if (high > fil_space_get_size(space)) {
+		low  = (offset / buf_read_ahead_random_area)
+			* buf_read_ahead_random_area;
+		high = (offset / buf_read_ahead_random_area + 1)
+			* buf_read_ahead_random_area;
+		high = s->max_page_number_for_io(high);
 
-		high = fil_space_get_size(space);
+		fil_space_release_for_io(s);
+	} else {
+		return 0;
 	}
 
 	if (buf_pool->n_pend_reads
@@ -495,22 +498,16 @@ buf_read_page(
 	ulint	offset,
 	trx_t*	trx)
 {
-	ib_int64_t	tablespace_version;
-	ulint		count;
 	dberr_t		err = DB_SUCCESS;
 
-	tablespace_version = fil_space_get_version(space_id);
-
 	FilSpace space(space_id, true);
 
 	if (space()) {
-
-		/* We do the i/o in the synchronous aio mode to save thread
-		switches: hence TRUE */
-		count = buf_read_page_low(&err, true, BUF_READ_ANY_PAGE, space_id,
-				  zip_size, FALSE,
-				  tablespace_version, offset, trx);
-
+		ulint count = buf_read_page_low(&err, /*sync=*/true,
+						BUF_READ_ANY_PAGE,
+						space_id, zip_size, FALSE,
+						space()->tablespace_version,
+						offset, trx);
 		srv_stats.buf_pool_reads.add(count);
 	}
 
@@ -683,13 +680,23 @@ buf_read_ahead_linear(
 		return(0);
 	}
 
-	/* Remember the tablespace version before we ask te tablespace size
-	below: if DISCARD + IMPORT changes the actual .ibd file meanwhile, we
-	do not try to read outside the bounds of the tablespace! */
+	uint32_t space_high_limit = 0;
 
-	tablespace_version = fil_space_get_version(space);
+	if (fil_space_t *s = fil_space_acquire_for_io(space)) {
+		/* Remember the tablespace version along with the
+		tablespace size: if DISCARD + IMPORT changes the
+		actual .ibd file meanwhile, we do not try to read
+		outside the bounds of the tablespace! */
+		tablespace_version = s->tablespace_version;
+
+		space_high_limit = s->max_page_number_for_io(ULINT_UNDEFINED);
+
+		fil_space_release_for_io(s);
+	} else {
+		return 0;
+	}
 
-	if (high > fil_space_get_size(space)) {
+	if (high > space_high_limit) {
 		/* The area is not whole, return */
 
 		return(0);
@@ -825,7 +832,7 @@ buf_read_ahead_linear(
 		return(0);
 	}
 
-	if (high > fil_space_get_size(space)) {
+	if (high > space_high_limit) {
 		/* The area is not whole, return */
 
 		return(0);
diff --git a/storage/xtradb/fil/fil0fil.cc b/storage/xtradb/fil/fil0fil.cc
index 4a982df3fda..d77d7320318 100644
--- a/storage/xtradb/fil/fil0fil.cc
+++ b/storage/xtradb/fil/fil0fil.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2014, 2019, MariaDB Corporation.
+Copyright (c) 2014, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -684,7 +684,7 @@ fil_node_open_file(
 #ifdef UNIV_HOTBACKUP
 add_size:
 #endif /* UNIV_HOTBACKUP */
-		space->size += node->size;
+		space->committed_size = space->size += node->size;
 	}
 
 	ulint atomic_writes = FSP_FLAGS_GET_ATOMIC_WRITES(space->flags);
@@ -1158,6 +1158,9 @@ retry:
 		ut_a(success);
 		/* InnoDB data files cannot shrink. */
 		ut_a(space->size >= size);
+		if (size > space->committed_size) {
+			space->committed_size = size;
+		}
 
 		/* There could be multiple concurrent I/O requests for
 		this tablespace (multiple threads trying to extend
@@ -1815,25 +1818,6 @@ fil_space_get_zip_size(
 	return(flags);
 }
 
-/*******************************************************************//**
-Checks if the pair space, page_no refers to an existing page in a tablespace
-file space. The tablespace must be cached in the memory cache.
-@return	TRUE if the address is meaningful */
-UNIV_INTERN
-ibool
-fil_check_adress_in_tablespace(
-/*===========================*/
-	ulint	id,	/*!< in: space id */
-	ulint	page_no)/*!< in: page number */
-{
-	if (fil_space_get_size(id) > page_no) {
-
-		return(TRUE);
-	}
-
-	return(FALSE);
-}
-
 /****************************************************************//**
 Initializes the tablespace memory cache. */
 UNIV_INTERN
diff --git a/storage/xtradb/fsp/fsp0fsp.cc b/storage/xtradb/fsp/fsp0fsp.cc
index 5604a1b48c5..e9d26a5932b 100644
--- a/storage/xtradb/fsp/fsp0fsp.cc
+++ b/storage/xtradb/fsp/fsp0fsp.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2018, MariaDB Corporation.
+Copyright (c) 2017, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -450,7 +450,7 @@ xdes_get_descriptor_with_space_hdr(
 	page_t*	descr_page;
 
 	ut_ad(mtr_memo_contains(mtr, fil_space_get_latch(space, NULL),
-				MTR_MEMO_X_LOCK));
+				MTR_MEMO_SPACE_X_LOCK));
 	ut_ad(mtr_memo_contains_page(mtr, sp_header, MTR_MEMO_PAGE_X_FIX));
 	ut_ad(page_offset(sp_header) == FSP_HEADER_OFFSET);
 	/* Read free limit and space size */
@@ -534,7 +534,7 @@ xdes_lst_get_descriptor(
 
 	ut_ad(mtr);
 	ut_ad(mtr_memo_contains(mtr, fil_space_get_latch(space, NULL),
-				MTR_MEMO_X_LOCK));
+				MTR_MEMO_SPACE_X_LOCK));
 	descr = fut_get_ptr(space, zip_size, lst_node, RW_X_LATCH, mtr)
 		- XDES_FLST_NODE;
 
@@ -690,7 +690,7 @@ fsp_header_init(ulint space_id, ulint size, mtr_t* mtr)
 
 	ut_ad(mtr);
 
-	mtr_x_lock(fil_space_get_latch(space_id, &flags), mtr);
+	mtr_x_space_lock(fil_space_get_latch(space_id, &flags), mtr);
 
 	zip_size = fsp_flags_get_zip_size(flags);
 	block = buf_page_create(space_id, 0, zip_size, mtr);
@@ -817,7 +817,7 @@ fsp_header_inc_size(
 
 	ut_ad(mtr);
 
-	mtr_x_lock(fil_space_get_latch(space, &flags), mtr);
+	mtr_x_space_lock(fil_space_get_latch(space, &flags), mtr);
 
 	header = fsp_get_space_header(space,
 				      fsp_flags_get_zip_size(flags),
@@ -846,7 +846,7 @@ fsp_header_get_tablespace_size(void)
 
 	mtr_start(&mtr);
 
-	mtr_x_lock(fil_space_get_latch(0, NULL), &mtr);
+	mtr_x_space_lock(fil_space_get_latch(0, NULL), &mtr);
 
 	header = fsp_get_space_header(0, 0, &mtr);
 
@@ -1073,7 +1073,6 @@ fsp_fill_free_list(
 	ulint	frag_n_used;
 	ulint	actual_increase;
 	ulint	i;
-	mtr_t	ibuf_mtr;
 
 	ut_ad(page_offset(header) == FSP_HEADER_OFFSET);
 
@@ -1141,26 +1140,17 @@ fsp_fill_free_list(
 						 MLOG_2BYTES, mtr);
 			}
 
-			/* Initialize the ibuf bitmap page in a separate
-			mini-transaction because it is low in the latching
-			order, and we must be able to release its latch
-			before returning from the fsp routine */
-
-			mtr_start(&ibuf_mtr);
-
 			block = buf_page_create(space,
-						    i + FSP_IBUF_BITMAP_OFFSET,
-						    zip_size, &ibuf_mtr);
+						i + FSP_IBUF_BITMAP_OFFSET,
+						zip_size, mtr);
 			buf_page_get(space, zip_size,
 				     i + FSP_IBUF_BITMAP_OFFSET,
-				     RW_X_LATCH, &ibuf_mtr);
+				     RW_X_LATCH, mtr);
 			buf_block_dbg_add_level(block, SYNC_FSP_PAGE);
 
-			fsp_init_file_page(block, &ibuf_mtr);
+			fsp_init_file_page(block, mtr);
 
-			ibuf_bitmap_page_init(block, &ibuf_mtr);
-
-			mtr_commit(&ibuf_mtr);
+			ibuf_bitmap_page_init(block, mtr);
 		}
 
 		descr = xdes_get_descriptor_with_space_hdr(header, space, i,
@@ -2047,7 +2037,7 @@ fseg_create_general(
 		header = byte_offset + buf_block_get_frame(block);
 	}
 
-	mtr_x_lock(latch, mtr);
+	mtr_x_space_lock(latch, mtr);
 
 	if (!has_done_reservation) {
 		success = fsp_reserve_free_extents(&n_reserved, space, 2,
@@ -2194,7 +2184,7 @@ fseg_n_reserved_pages(
 	latch = fil_space_get_latch(space, &flags);
 	zip_size = fsp_flags_get_zip_size(flags);
 
-	mtr_x_lock(latch, mtr);
+	mtr_x_space_lock(latch, mtr);
 
 	inode = fseg_inode_get(header, space, zip_size, mtr);
 
@@ -2617,7 +2607,7 @@ fseg_alloc_free_page_general(
 
 	zip_size = fsp_flags_get_zip_size(flags);
 
-	mtr_x_lock(latch, mtr);
+	mtr_x_space_lock(latch, mtr);
 
 	inode = fseg_inode_get(seg_header, space, zip_size, mtr);
 
@@ -2734,7 +2724,7 @@ fsp_reserve_free_extents(
 	latch = fil_space_get_latch(space, &flags);
 	zip_size = fsp_flags_get_zip_size(flags);
 
-	mtr_x_lock(latch, mtr);
+	mtr_x_space_lock(latch, mtr);
 
 	space_header = fsp_get_space_header(space, zip_size, mtr);
 try_again:
@@ -2873,7 +2863,7 @@ fsp_get_available_space_in_free_extents(
 
 	zip_size = fsp_flags_get_zip_size(flags);
 
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	mutex_exit(&dict_sys->mutex);
 
@@ -3169,7 +3159,7 @@ fseg_free_page(
 	latch = fil_space_get_latch(space, &flags);
 	zip_size = fsp_flags_get_zip_size(flags);
 
-	mtr_x_lock(latch, mtr);
+	mtr_x_space_lock(latch, mtr);
 
 	seg_inode = fseg_inode_get(seg_header, space, zip_size, mtr);
 
@@ -3203,7 +3193,7 @@ fseg_page_is_free(
 	zip_size = dict_tf_get_zip_size(flags);
 
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	seg_inode = fseg_inode_get(seg_header, space, zip_size, &mtr);
 
@@ -3328,7 +3318,7 @@ fseg_free_step(
 	latch = fil_space_get_latch(space, &flags);
 	zip_size = fsp_flags_get_zip_size(flags);
 
-	mtr_x_lock(latch, mtr);
+	mtr_x_space_lock(latch, mtr);
 
 	descr = xdes_get_descriptor(space, zip_size, header_page, mtr);
 
@@ -3415,7 +3405,7 @@ fseg_free_step_not_header(
 	latch = fil_space_get_latch(space, &flags);
 	zip_size = fsp_flags_get_zip_size(flags);
 
-	mtr_x_lock(latch, mtr);
+	mtr_x_space_lock(latch, mtr);
 
 	inode = fseg_inode_get(header, space, zip_size, mtr);
 
@@ -3541,7 +3531,7 @@ fseg_validate_low(
 		ulint	zip_size;
 
 		mtr_start(&mtr);
-		mtr_x_lock(fil_space_get_latch(space, &flags), &mtr);
+		mtr_x_space_lock(fil_space_get_latch(space, &flags), &mtr);
 		zip_size = fsp_flags_get_zip_size(flags);
 
 		descr = xdes_lst_get_descriptor(space, zip_size,
@@ -3564,7 +3554,7 @@ fseg_validate_low(
 		ulint	zip_size;
 
 		mtr_start(&mtr);
-		mtr_x_lock(fil_space_get_latch(space, &flags), &mtr);
+		mtr_x_space_lock(fil_space_get_latch(space, &flags), &mtr);
 		zip_size = fsp_flags_get_zip_size(flags);
 
 		descr = xdes_lst_get_descriptor(space, zip_size,
@@ -3590,7 +3580,7 @@ fseg_validate_low(
 		ulint	zip_size;
 
 		mtr_start(&mtr);
-		mtr_x_lock(fil_space_get_latch(space, &flags), &mtr);
+		mtr_x_space_lock(fil_space_get_latch(space, &flags), &mtr);
 		zip_size = fsp_flags_get_zip_size(flags);
 
 		descr = xdes_lst_get_descriptor(space, zip_size,
@@ -3628,7 +3618,7 @@ fseg_validate(
 
 	space = page_get_space_id(page_align(header));
 
-	mtr_x_lock(fil_space_get_latch(space, &flags), mtr);
+	mtr_x_space_lock(fil_space_get_latch(space, &flags), mtr);
 	zip_size = fsp_flags_get_zip_size(flags);
 
 	inode = fseg_inode_get(header, space, zip_size, mtr);
@@ -3704,7 +3694,7 @@ fseg_print(
 
 	space = page_get_space_id(page_align(header));
 
-	mtr_x_lock(fil_space_get_latch(space, &flags), mtr);
+	mtr_x_space_lock(fil_space_get_latch(space, &flags), mtr);
 	zip_size = fsp_flags_get_zip_size(flags);
 
 	inode = fseg_inode_get(header, space, zip_size, mtr);
@@ -3753,10 +3743,10 @@ fsp_validate(
 	/* Start first a mini-transaction mtr2 to lock out all other threads
 	from the fsp system */
 	mtr_start(&mtr2);
-	mtr_x_lock(latch, &mtr2);
+	mtr_x_space_lock(latch, &mtr2);
 
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 
@@ -3783,7 +3773,7 @@ fsp_validate(
 
 	/* Validate FSP_FREE list */
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 	node_addr = flst_get_first(header + FSP_FREE, &mtr);
@@ -3792,7 +3782,7 @@ fsp_validate(
 
 	while (!fil_addr_is_null(node_addr)) {
 		mtr_start(&mtr);
-		mtr_x_lock(latch, &mtr);
+		mtr_x_space_lock(latch, &mtr);
 
 		descr_count++;
 		descr = xdes_lst_get_descriptor(space, zip_size,
@@ -3807,7 +3797,7 @@ fsp_validate(
 
 	/* Validate FSP_FREE_FRAG list */
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 	node_addr = flst_get_first(header + FSP_FREE_FRAG, &mtr);
@@ -3816,7 +3806,7 @@ fsp_validate(
 
 	while (!fil_addr_is_null(node_addr)) {
 		mtr_start(&mtr);
-		mtr_x_lock(latch, &mtr);
+		mtr_x_space_lock(latch, &mtr);
 
 		descr_count++;
 		descr = xdes_lst_get_descriptor(space, zip_size,
@@ -3834,7 +3824,7 @@ fsp_validate(
 
 	/* Validate FSP_FULL_FRAG list */
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 	node_addr = flst_get_first(header + FSP_FULL_FRAG, &mtr);
@@ -3843,7 +3833,7 @@ fsp_validate(
 
 	while (!fil_addr_is_null(node_addr)) {
 		mtr_start(&mtr);
-		mtr_x_lock(latch, &mtr);
+		mtr_x_space_lock(latch, &mtr);
 
 		descr_count++;
 		descr = xdes_lst_get_descriptor(space, zip_size,
@@ -3858,7 +3848,7 @@ fsp_validate(
 
 	/* Validate segments */
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 
@@ -3873,7 +3863,7 @@ fsp_validate(
 		n = 0;
 		do {
 			mtr_start(&mtr);
-			mtr_x_lock(latch, &mtr);
+			mtr_x_space_lock(latch, &mtr);
 
 			seg_inode_page = fut_get_ptr(
 				space, zip_size, node_addr, RW_X_LATCH, &mtr)
@@ -3902,7 +3892,7 @@ fsp_validate(
 	}
 
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 
@@ -3918,7 +3908,7 @@ fsp_validate(
 
 		do {
 			mtr_start(&mtr);
-			mtr_x_lock(latch, &mtr);
+			mtr_x_space_lock(latch, &mtr);
 
 			seg_inode_page = fut_get_ptr(
 				space, zip_size, node_addr, RW_X_LATCH, &mtr)
@@ -4002,11 +3992,11 @@ fsp_print(
 
 	mtr_start(&mtr2);
 
-	mtr_x_lock(latch, &mtr2);
+	mtr_x_space_lock(latch, &mtr2);
 
 	mtr_start(&mtr);
 
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 
@@ -4038,7 +4028,7 @@ fsp_print(
 	/* Print segments */
 
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 
@@ -4053,7 +4043,7 @@ fsp_print(
 		do {
 
 			mtr_start(&mtr);
-			mtr_x_lock(latch, &mtr);
+			mtr_x_space_lock(latch, &mtr);
 
 			seg_inode_page = fut_get_ptr(
 				space, zip_size, node_addr, RW_X_LATCH, &mtr)
@@ -4075,7 +4065,7 @@ fsp_print(
 	}
 
 	mtr_start(&mtr);
-	mtr_x_lock(latch, &mtr);
+	mtr_x_space_lock(latch, &mtr);
 
 	header = fsp_get_space_header(space, zip_size, &mtr);
 
@@ -4090,7 +4080,7 @@ fsp_print(
 		do {
 
 			mtr_start(&mtr);
-			mtr_x_lock(latch, &mtr);
+			mtr_x_space_lock(latch, &mtr);
 
 			seg_inode_page = fut_get_ptr(
 				space, zip_size, node_addr, RW_X_LATCH, &mtr)
@@ -4147,7 +4137,8 @@ fsp_page_is_free_func(
 
 	ut_ad(mtr);
 
-	mtr_x_lock_func(fil_space_get_latch(space, &flags), file, line, mtr);
+	mtr_x_space_lock_func(fil_space_get_latch(space, &flags), file, line,
+			      mtr);
 	ulint zip_size = fsp_flags_get_zip_size(flags);
 
 	xdes_t* descr = xdes_get_descriptor(space, zip_size, page_no, mtr);
diff --git a/storage/xtradb/ibuf/ibuf0ibuf.cc b/storage/xtradb/ibuf/ibuf0ibuf.cc
index cd65ea15729..6f11daa7363 100644
--- a/storage/xtradb/ibuf/ibuf0ibuf.cc
+++ b/storage/xtradb/ibuf/ibuf0ibuf.cc
@@ -588,7 +588,7 @@ ibuf_init_at_db_start(void)
 
 	mutex_enter(&ibuf_mutex);
 
-	mtr_x_lock(fil_space_get_latch(IBUF_SPACE_ID, NULL), &mtr);
+	mtr_x_space_lock(fil_space_get_latch(IBUF_SPACE_ID, NULL), &mtr);
 
 	header_page = ibuf_header_page_get(&mtr);
 
@@ -2139,7 +2139,7 @@ ibuf_add_free_page(void)
 
 	/* Acquire the fsp latch before the ibuf header, obeying the latching
 	order */
-	mtr_x_lock(fil_space_get_latch(IBUF_SPACE_ID, &flags), &mtr);
+	mtr_x_space_lock(fil_space_get_latch(IBUF_SPACE_ID, &flags), &mtr);
 	zip_size = fsp_flags_get_zip_size(flags);
 
 	header_page = ibuf_header_page_get(&mtr);
@@ -2223,7 +2223,7 @@ ibuf_remove_free_page(void)
 
 	/* Acquire the fsp latch before the ibuf header, obeying the latching
 	order */
-	mtr_x_lock(fil_space_get_latch(IBUF_SPACE_ID, &flags), &mtr);
+	mtr_x_space_lock(fil_space_get_latch(IBUF_SPACE_ID, &flags), &mtr);
 	zip_size = fsp_flags_get_zip_size(flags);
 
 	header_page = ibuf_header_page_get(&mtr);
diff --git a/storage/xtradb/include/fil0fil.h b/storage/xtradb/include/fil0fil.h
index a4274f4d8a6..6a823e131ac 100644
--- a/storage/xtradb/include/fil0fil.h
+++ b/storage/xtradb/include/fil0fil.h
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2013, 2019, MariaDB Corporation.
+Copyright (c) 2013, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -300,6 +300,8 @@ struct fil_space_t {
 				/*!< recovered tablespace size in pages;
 				0 if no size change was read from the redo log,
 				or if the size change was implemented */
+  /** the committed size of the tablespace in pages */
+  ulint committed_size;
 	ulint		flags;	/*!< FSP_SPACE_FLAGS and FSP_FLAGS_MEM_ flags;
 				see fsp0fsp.h,
 				fsp_flags_is_valid(),
@@ -364,6 +366,15 @@ struct fil_space_t {
 	{
 		return stop_new_ops;
 	}
+
+  /** Clamp a page number for batched I/O, such as read-ahead.
+  @param offset   page number limit
+  @return offset clamped to the tablespace size */
+  ulint max_page_number_for_io(ulint offset) const
+  {
+    const ulint limit= committed_size;
+    return limit > offset ? offset : limit;
+  }
 };
 
 /** Value of fil_space_t::magic_n */
@@ -574,16 +585,6 @@ ulint
 fil_space_get_zip_size(
 /*===================*/
 	ulint	id);	/*!< in: space id */
-/*******************************************************************//**
-Checks if the pair space, page_no refers to an existing page in a tablespace
-file space. The tablespace must be cached in the memory cache.
-@return	TRUE if the address is meaningful */
-UNIV_INTERN
-ibool
-fil_check_adress_in_tablespace(
-/*===========================*/
-	ulint	id,	/*!< in: space id */
-	ulint	page_no);/*!< in: page number */
 /****************************************************************//**
 Initializes the tablespace memory cache. */
 UNIV_INTERN
diff --git a/storage/xtradb/include/mtr0mtr.h b/storage/xtradb/include/mtr0mtr.h
index 2d3da4d2a25..7d115eed5fd 100644
--- a/storage/xtradb/include/mtr0mtr.h
+++ b/storage/xtradb/include/mtr0mtr.h
@@ -2,6 +2,7 @@
 
 Copyright (c) 1995, 2016, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2012, Facebook Inc.
+Copyright (c) 2013, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -57,6 +58,7 @@ first 3 values must be RW_S_LATCH, RW_X_LATCH, RW_NO_LATCH */
 #endif /* UNIV_DEBUG */
 #define	MTR_MEMO_S_LOCK		55
 #define	MTR_MEMO_X_LOCK		56
+#define	MTR_MEMO_SPACE_X_LOCK	57
 
 /** @name Log item types
 The log items are declared 'byte' so that the compiler can warn if val
@@ -293,6 +295,8 @@ This macro locks an rw-lock in s-mode. */
 This macro locks an rw-lock in x-mode. */
 #define mtr_x_lock(B, MTR)	mtr_x_lock_func((B), __FILE__, __LINE__,\
 						(MTR))
+#define mtr_x_space_lock(B, MTR) mtr_x_space_lock_func(B, __FILE__, __LINE__,\
+						       MTR)
 /*********************************************************************//**
 NOTE! Use the macro above!
 Locks a lock in s-mode. */
@@ -315,6 +319,14 @@ mtr_x_lock_func(
 	const char*	file,	/*!< in: file name */
 	ulint		line,	/*!< in: line number */
 	mtr_t*		mtr);	/*!< in: mtr */
+
+/** Acquire exclusive tablespace latch.
+@param lock   fil_space_t::latch
+@param file   source code file name of the caller
+@param line   source code line number of the caller
+@param mtr    mini-transaction */
+inline void mtr_x_space_lock_func(prio_rw_lock_t *lock,
+                                  const char *file, ulint line, mtr_t *mtr);
 #endif /* !UNIV_HOTBACKUP */
 
 /***************************************************//**
diff --git a/storage/xtradb/include/mtr0mtr.ic b/storage/xtradb/include/mtr0mtr.ic
index a44728463ae..0aea0994267 100644
--- a/storage/xtradb/include/mtr0mtr.ic
+++ b/storage/xtradb/include/mtr0mtr.ic
@@ -1,6 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2016, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -78,7 +79,7 @@ mtr_memo_push(
 
 	ut_ad(object);
 	ut_ad(type >= MTR_MEMO_PAGE_S_FIX);
-	ut_ad(type <= MTR_MEMO_X_LOCK);
+	ut_ad(type <= MTR_MEMO_SPACE_X_LOCK);
 	ut_ad(mtr);
 	ut_ad(mtr->magic_n == MTR_MAGIC_N);
 	ut_ad(mtr->state == MTR_ACTIVE);
@@ -293,4 +294,16 @@ mtr_x_lock_func(
 
 	mtr_memo_push(mtr, lock, MTR_MEMO_X_LOCK);
 }
+
+/** Acquire exclusive tablespace latch.
+@param lock   fil_space_t::latch
+@param file   source code file name of the caller
+@param line   source code line number of the caller
+@param mtr    mini-transaction */
+inline void mtr_x_space_lock_func(prio_rw_lock_t *lock,
+                                  const char *file, ulint line, mtr_t *mtr)
+{
+  rw_lock_x_lock_inline(lock, 0, file, line);
+  mtr_memo_push(mtr, lock, MTR_MEMO_SPACE_X_LOCK);
+}
 #endif /* !UNIV_HOTBACKUP */
diff --git a/storage/xtradb/mtr/mtr0mtr.cc b/storage/xtradb/mtr/mtr0mtr.cc
index 77af6e9eb60..a04f9cc84a3 100644
--- a/storage/xtradb/mtr/mtr0mtr.cc
+++ b/storage/xtradb/mtr/mtr0mtr.cc
@@ -1,6 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2016, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -88,6 +89,16 @@ mtr_memo_slot_release_func(
 	case MTR_MEMO_X_LOCK:
 		rw_lock_x_unlock((prio_rw_lock_t*) object);
 		break;
+	case MTR_MEMO_SPACE_X_LOCK:
+		{
+			fil_space_t* space = reinterpret_cast<fil_space_t*>(
+				static_cast<char*>(object)
+				- reinterpret_cast<char*>(
+					&static_cast<fil_space_t*>(0)->latch));
+			space->committed_size = space->size;
+			rw_lock_x_unlock(&space->latch);
+		}
+		break;
 #ifdef UNIV_DEBUG
 	default:
 		ut_ad(slot->type == MTR_MEMO_MODIFY);
diff --git a/storage/xtradb/row/row0import.cc b/storage/xtradb/row/row0import.cc
index bafea49fae9..f3375f838ba 100644
--- a/storage/xtradb/row/row0import.cc
+++ b/storage/xtradb/row/row0import.cc
@@ -561,14 +561,6 @@ protected:
 	/** Space id of the file being iterated over. */
 	ulint			m_space;
 
-	/** Minimum page number for which the free list has not been
-	initialized: the pages >= this limit are, by definition, free;
-	note that in a single-table tablespace where size < 64 pages,
-	this number is 64, i.e., we have initialized the space about
-	the first extent, but have not physically allocted those pages
-	to the file. @see FSP_LIMIT. */
-	ulint			m_free_limit;
-
 	/** Current size of the space in pages */
 	ulint			m_size;
 
@@ -647,7 +639,6 @@ AbstractCallback::init(
 	ut_a(m_space == ULINT_UNDEFINED);
 
 	m_size  = mach_read_from_4(page + FSP_SIZE);
-	m_free_limit = mach_read_from_4(page + FSP_FREE_LIMIT);
 	m_space = mach_read_from_4(page + FSP_HEADER_OFFSET + FSP_SPACE_ID);
 
 	return set_current_xdes(0, page);
diff --git a/storage/xtradb/srv/srv0start.cc b/storage/xtradb/srv/srv0start.cc
index 6ea430699d4..0ad755c1e3a 100644
--- a/storage/xtradb/srv/srv0start.cc
+++ b/storage/xtradb/srv/srv0start.cc
@@ -3,7 +3,7 @@
 Copyright (c) 1996, 2017, Oracle and/or its affiliates. All rights reserved.
 Copyright (c) 2008, Google Inc.
 Copyright (c) 2009, Percona Inc.
-Copyright (c) 2013, 2019, MariaDB Corporation.
+Copyright (c) 2013, 2020, MariaDB Corporation.
 
 Portions of this file contain modifications contributed and copyrighted by
 Google, Inc. Those modifications are gratefully acknowledged and are described
@@ -1240,6 +1240,10 @@ check_first_page:
 		}
 	}
 
+	if (fil_space_t* s = fil_space_get(0)) {
+		s->committed_size = s->size;
+	}
+
 	return(DB_SUCCESS);
 }
 
@@ -1408,6 +1412,10 @@ srv_undo_tablespace_open(
 		if (fil_node_create(name, (ulint) n_pages, space, FALSE)) {
 			err = DB_SUCCESS;
 		}
+
+		if (fil_space_t* s = fil_space_get(space)) {
+			s->committed_size = n_pages;
+		}
 	}
 
 	return(err);
diff --git a/storage/xtradb/trx/trx0rseg.cc b/storage/xtradb/trx/trx0rseg.cc
index 1d0eb6d29fd..8ce6fb6729f 100644
--- a/storage/xtradb/trx/trx0rseg.cc
+++ b/storage/xtradb/trx/trx0rseg.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1996, 2011, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, MariaDB Corporation.
+Copyright (c) 2017, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -65,7 +65,7 @@ trx_rseg_header_create(
 
 	ut_ad(mtr);
 	ut_ad(mtr_memo_contains(mtr, fil_space_get_latch(space, NULL),
-				MTR_MEMO_X_LOCK));
+				MTR_MEMO_SPACE_X_LOCK));
 
 	/* Allocate a new file segment for the rollback segment */
 	block = fseg_create(space, 0, TRX_RSEG + TRX_RSEG_FSEG_HEADER, mtr);
@@ -312,7 +312,7 @@ trx_rseg_create(ulint space)
 
 	/* To obey the latching order, acquire the file space
 	x-latch before the trx_sys->mutex. */
-	mtr_x_lock(fil_space_get_latch(space, NULL), &mtr);
+	mtr_x_space_lock(fil_space_get_latch(space, NULL), &mtr);
 
 	slot_no = trx_sysf_rseg_find_free(&mtr);
 
diff --git a/storage/xtradb/trx/trx0sys.cc b/storage/xtradb/trx/trx0sys.cc
index fcdce291cf0..94a79a1f944 100644
--- a/storage/xtradb/trx/trx0sys.cc
+++ b/storage/xtradb/trx/trx0sys.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1996, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2018, MariaDB Corporation.
+Copyright (c) 2017, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -554,7 +554,7 @@ trx_sysf_create(
 	then enter the kernel: we must do it in this order to conform
 	to the latching order rules. */
 
-	mtr_x_lock(fil_space_get_latch(TRX_SYS_SPACE, NULL), mtr);
+	mtr_x_space_lock(fil_space_get_latch(TRX_SYS_SPACE, NULL), mtr);
 
 	/* Create the trx sys file block in a new allocated file segment */
 	block = fseg_create(TRX_SYS_SPACE, 0, TRX_SYS + TRX_SYS_FSEG_HEADER,