MDEV-12266: Add fil_system.sys_space, temp_space

Add fil_system_t::sys_space, fil_system_t::temp_space.
These will replace lookups for TRX_SYS_SPACE or SRV_TMP_SPACE_ID.

mtr_t::m_undo_space, mtr_t::m_sys_space: Remove.

mtr_t::set_sys_modified(): Remove.

fil_space_get_type(), fil_space_get_n_reserved_extents(): Remove.

fsp_header_get_tablespace_size(), fsp_header_inc_size():
Merge to the only caller, innobase_start_or_create_for_mysql().

14 files changed, 139 insertions, 366 deletions

diff --git a/extra/mariabackup/xtrabackup.cc b/extra/mariabackup/xtrabackup.cc
index 6e16e44153d..ac6101575e4 100644
--- a/extra/mariabackup/xtrabackup.cc
+++ b/extra/mariabackup/xtrabackup.cc
@@ -2779,11 +2779,11 @@ xb_load_single_table_tablespace(
 
 		/* by opening the tablespace we forcing node and space objects
 		in the cache to be populated with fields from space header */
-		fil_space_open(space->name);
+		space->open();
 
 		if (srv_operation == SRV_OPERATION_RESTORE_DELTA
 		    || xb_close_files) {
-			fil_space_close(space->name);
+			space->close();
 		}
 	}
 
diff --git a/storage/innobase/fil/fil0fil.cc b/storage/innobase/fil/fil0fil.cc
index ff956f3eb89..6f7f4fef293 100644
--- a/storage/innobase/fil/fil0fil.cc
+++ b/storage/innobase/fil/fil0fil.cc
@@ -393,28 +393,6 @@ fil_space_get_latch(
 	return(&(space->latch));
 }
 
-/** Gets the type of a file space.
-@param[in]	id	tablespace identifier
-@return file type */
-fil_type_t
-fil_space_get_type(
-	ulint	id)
-{
-	fil_space_t*	space;
-
-	ut_ad(fil_system.is_initialised());
-
-	mutex_enter(&fil_system.mutex);
-
-	space = fil_space_get_by_id(id);
-
-	ut_a(space);
-
-	mutex_exit(&fil_system.mutex);
-
-	return(space->purpose);
-}
-
 /** Note that a tablespace has been imported.
 It is initially marked as FIL_TYPE_IMPORT so that no logging is
 done during the import process when the space ID is stamped to each page.
@@ -1373,6 +1351,12 @@ fil_space_detach(
 
 		fil_node_close_to_free(fil_node, space);
 	}
+
+	if (space == fil_system.sys_space) {
+		fil_system.sys_space = NULL;
+	} else if (space == fil_system.temp_space) {
+		fil_system.temp_space = NULL;
+	}
 }
 
 /** Free a tablespace object on which fil_space_detach() was invoked.
@@ -1828,58 +1812,47 @@ fil_space_get_flags(
 	return(flags);
 }
 
-/** Open each fil_node_t of a named fil_space_t if not already open.
-@param[in]	name	Tablespace name
-@return true if all nodes are open  */
-bool
-fil_space_open(
-	const char*	name)
+/** Open each file. Only invoked on fil_system.temp_space.
+@return whether all files were opened */
+bool fil_space_t::open()
 {
 	ut_ad(fil_system.is_initialised());
 
 	mutex_enter(&fil_system.mutex);
+	ut_ad(this == fil_system.temp_space
+	      || srv_operation == SRV_OPERATION_BACKUP
+	      || srv_operation == SRV_OPERATION_RESTORE
+	      || srv_operation == SRV_OPERATION_RESTORE_DELTA);
 
-	fil_space_t*	space = fil_space_get_by_name(name);
-	fil_node_t*	node;
-
-	for (node = UT_LIST_GET_FIRST(space->chain);
+	for (fil_node_t* node = UT_LIST_GET_FIRST(chain);
 	     node != NULL;
 	     node = UT_LIST_GET_NEXT(chain, node)) {
-
-		if (!node->is_open()
-		    && !fil_node_open_file(node)) {
+		if (!node->is_open() && !fil_node_open_file(node)) {
 			mutex_exit(&fil_system.mutex);
-			return(false);
+			return false;
 		}
 	}
 
 	mutex_exit(&fil_system.mutex);
-
-	return(true);
+	return true;
 }
 
-/** Close each fil_node_t of a named fil_space_t if open.
-@param[in]	name	Tablespace name */
-void
-fil_space_close(
-	const char*	name)
+/** Close each file. Only invoked on fil_system.temp_space. */
+void fil_space_t::close()
 {
 	if (!fil_system.is_initialised()) {
 		return;
 	}
 
 	mutex_enter(&fil_system.mutex);
+	ut_ad(this == fil_system.temp_space
+	      || srv_operation == SRV_OPERATION_BACKUP
+	      || srv_operation == SRV_OPERATION_RESTORE
+	      || srv_operation == SRV_OPERATION_RESTORE_DELTA);
 
-	fil_space_t*	space = fil_space_get_by_name(name);
-	if (space == NULL) {
-		mutex_exit(&fil_system.mutex);
-		return;
-	}
-
-	for (fil_node_t* node = UT_LIST_GET_FIRST(space->chain);
+	for (fil_node_t* node = UT_LIST_GET_FIRST(chain);
 	     node != NULL;
 	     node = UT_LIST_GET_NEXT(chain, node)) {
-
 		if (node->is_open()) {
 			fil_node_close_file(node);
 		}
@@ -1940,6 +1913,8 @@ void fil_system_t::close()
 	ut_a(!UT_LIST_GET_LEN(LRU));
 	ut_a(!UT_LIST_GET_LEN(unflushed_spaces));
 	ut_a(!UT_LIST_GET_LEN(space_list));
+	ut_ad(!sys_space);
+	ut_ad(!temp_space);
 
 	if (is_initialised()) {
 		m_initialised = false;
@@ -4854,32 +4829,6 @@ fil_space_release_free_extents(
 	mutex_exit(&fil_system.mutex);
 }
 
-/*******************************************************************//**
-Gets the number of reserved extents. If the database is silent, this number
-should be zero. */
-ulint
-fil_space_get_n_reserved_extents(
-/*=============================*/
-	ulint	id)		/*!< in: space id */
-{
-	fil_space_t*	space;
-	ulint		n;
-
-	ut_ad(fil_system.is_initialised());
-
-	mutex_enter(&fil_system.mutex);
-
-	space = fil_space_get_by_id(id);
-
-	ut_a(space);
-
-	n = space->n_reserved_extents;
-
-	mutex_exit(&fil_system.mutex);
-
-	return(n);
-}
-
 /*============================ FILE I/O ================================*/
 
 /********************************************************************//**
@@ -5498,6 +5447,10 @@ struct	Check {
 		Check	check;
 		ut_list_validate(space->chain, check);
 		ut_a(space->size == check.size);
+		ut_ad(space->id != TRX_SYS_SPACE
+		      || space == fil_system.sys_space);
+		ut_ad(space->id != SRV_TMP_SPACE_ID
+		      || space == fil_system.temp_space);
 		return(check.n_open);
 	}
 };
diff --git a/storage/innobase/fsp/fsp0fsp.cc b/storage/innobase/fsp/fsp0fsp.cc
index a337b6f171f..fb1a650b3f5 100644
--- a/storage/innobase/fsp/fsp0fsp.cc
+++ b/storage/innobase/fsp/fsp0fsp.cc
@@ -812,63 +812,6 @@ fsp_header_get_space_id(
 	return(id);
 }
 
-/**********************************************************************//**
-Increases the space size field of a space. */
-void
-fsp_header_inc_size(
-/*================*/
-	ulint	space_id,	/*!< in: space id */
-	ulint	size_inc,	/*!< in: size increment in pages */
-	mtr_t*	mtr)		/*!< in/out: mini-transaction */
-{
-	fsp_header_t*	header;
-	ulint		size;
-
-	ut_ad(mtr);
-
-	fil_space_t*	space = mtr_x_lock_space(space_id, mtr);
-	ut_d(fsp_space_modify_check(space, mtr));
-
-	header = fsp_get_space_header(
-		space, page_size_t(space->flags), mtr);
-
-	size = mach_read_from_4(header + FSP_SIZE);
-	ut_ad(size == space->size_in_header);
-
-	size += size_inc;
-
-	mlog_write_ulint(header + FSP_SIZE, size, MLOG_4BYTES, mtr);
-	space->size_in_header = size;
-}
-
-/**********************************************************************//**
-Gets the size of the system tablespace from the tablespace header.  If
-we do not have an auto-extending data file, this should be equal to
-the size of the data files.  If there is an auto-extending data file,
-this can be smaller.
-@return size in pages */
-ulint
-fsp_header_get_tablespace_size(void)
-/*================================*/
-{
-	fsp_header_t*	header;
-	ulint		size;
-	mtr_t		mtr;
-
-	mtr_start(&mtr);
-
-	fil_space_t*	space = mtr_x_lock_space(TRX_SYS_SPACE, &mtr);
-
-	header = fsp_get_space_header(space, univ_page_size, &mtr);
-
-	size = mach_read_from_4(header + FSP_SIZE);
-	ut_ad(space->size_in_header == size);
-
-	mtr_commit(&mtr);
-
-	return(size);
-}
-
 /** Try to extend a single-table tablespace so that a page would fit in the
 data file.
 @param[in,out]	space	tablespace
diff --git a/storage/innobase/fsp/fsp0sysspace.cc b/storage/innobase/fsp/fsp0sysspace.cc
index e9f04cbd6c5..b7bdb8609da 100644
--- a/storage/innobase/fsp/fsp0sysspace.cc
+++ b/storage/innobase/fsp/fsp0sysspace.cc
@@ -912,15 +912,19 @@ SysTablespace::open_or_create(
 		it->close();
 		it->m_exists = true;
 
-		if (it == begin) {
-			/* First data file. */
-
-			/* Create the tablespace entry for the multi-file
-			tablespace in the tablespace manager. */
-			space = fil_space_create(
-				name(), space_id(), flags(), is_temp
-				? FIL_TYPE_TEMPORARY : FIL_TYPE_TABLESPACE,
-				NULL);
+		if (it != begin) {
+		} else if (is_temp) {
+			ut_ad(!fil_system.temp_space);
+			ut_ad(space_id() == SRV_TMP_SPACE_ID);
+			space = fil_system.temp_space = fil_space_create(
+				name(), SRV_TMP_SPACE_ID, flags(),
+				FIL_TYPE_TEMPORARY, NULL);
+		} else {
+			ut_ad(!fil_system.sys_space);
+			ut_ad(space_id() == TRX_SYS_SPACE);
+			space = fil_system.sys_space = fil_space_create(
+				name(), TRX_SYS_SPACE, flags(),
+				FIL_TYPE_TABLESPACE, NULL);
 		}
 
 		ut_a(fil_validate());
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
index 5c017e91776..fff9ec45455 100644
--- a/storage/innobase/handler/ha_innodb.cc
+++ b/storage/innobase/handler/ha_innodb.cc
@@ -3489,9 +3489,12 @@ innobase_space_shutdown()
 {
 	DBUG_ENTER("innobase_space_shutdown");
 
+	if (fil_system.temp_space) {
+		fil_system.temp_space->close();
+	}
+
 	srv_sys_space.shutdown();
 	if (srv_tmp_space.get_sanity_check_status()) {
-		fil_space_close(srv_tmp_space.name());
 		srv_tmp_space.delete_files();
 	}
 	srv_tmp_space.shutdown();
diff --git a/storage/innobase/ibuf/ibuf0ibuf.cc b/storage/innobase/ibuf/ibuf0ibuf.cc
index 8b132b62255..a88084c369f 100644
--- a/storage/innobase/ibuf/ibuf0ibuf.cc
+++ b/storage/innobase/ibuf/ibuf0ibuf.cc
@@ -522,7 +522,9 @@ ibuf_init_at_db_start(void)
 
 	mtr_start(&mtr);
 
-	mtr_x_lock_space(IBUF_SPACE_ID, &mtr);
+	compile_time_assert(IBUF_SPACE_ID == TRX_SYS_SPACE);
+	compile_time_assert(IBUF_SPACE_ID == 0);
+	mtr_x_lock(&fil_system.sys_space->latch, &mtr);
 
 	mutex_enter(&ibuf_mutex);
 
@@ -1151,7 +1153,8 @@ ibuf_page_low(
 		return(FALSE);
 	}
 
-	ut_ad(fil_space_get_type(IBUF_SPACE_ID) == FIL_TYPE_TABLESPACE);
+	compile_time_assert(IBUF_SPACE_ID == 0);
+	ut_ad(fil_system.sys_space->purpose == FIL_TYPE_TABLESPACE);
 
 #ifdef UNIV_DEBUG
 	if (!x_latch) {
@@ -2028,11 +2031,9 @@ ibuf_add_free_page(void)
 	page_t*		bitmap_page;
 
 	mtr_start(&mtr);
-	fil_space_t* space = mtr.set_sys_modified();
-
 	/* Acquire the fsp latch before the ibuf header, obeying the latching
 	order */
-	mtr_x_lock(&space->latch, &mtr);
+	mtr_x_lock(&fil_system.sys_space->latch, &mtr);
 	header_page = ibuf_header_page_get(&mtr);
 
 	/* Allocate a new page: NOTE that if the page has been a part of a
@@ -2078,13 +2079,11 @@ ibuf_add_free_page(void)
 	(level 2 page) */
 
 	const page_id_t		page_id(IBUF_SPACE_ID, block->page.id.page_no());
-	const page_size_t	page_size(space->flags);
-
-	bitmap_page = ibuf_bitmap_get_map_page(page_id, page_size, &mtr);
+	bitmap_page = ibuf_bitmap_get_map_page(page_id, univ_page_size, &mtr);
 
 	mutex_exit(&ibuf_mutex);
 
-	ibuf_bitmap_page_set_bits(bitmap_page, page_id, page_size,
+	ibuf_bitmap_page_set_bits(bitmap_page, page_id, univ_page_size,
 				  IBUF_BITMAP_IBUF, TRUE, &mtr);
 
 	ibuf_mtr_commit(&mtr);
@@ -2110,13 +2109,10 @@ ibuf_remove_free_page(void)
 	log_free_check();
 
 	mtr_start(&mtr);
-	fil_space_t*		space = mtr.set_sys_modified();
-	const page_size_t	page_size(space->flags);
-
 	/* Acquire the fsp latch before the ibuf header, obeying the latching
 	order */
 
-	mtr_x_lock(&space->latch, &mtr);
+	mtr_x_lock(&fil_system.sys_space->latch, &mtr);
 	header_page = ibuf_header_page_get(&mtr);
 
 	/* Prevent pessimistic inserts to insert buffer trees for a while */
@@ -2195,12 +2191,12 @@ ibuf_remove_free_page(void)
 	/* Set the bit indicating that this page is no more an ibuf tree page
 	(level 2 page) */
 
-	bitmap_page = ibuf_bitmap_get_map_page(page_id, page_size, &mtr);
+	bitmap_page = ibuf_bitmap_get_map_page(page_id, univ_page_size, &mtr);
 
 	mutex_exit(&ibuf_mutex);
 
 	ibuf_bitmap_page_set_bits(
-		bitmap_page, page_id, page_size, IBUF_BITMAP_IBUF, FALSE,
+		bitmap_page, page_id, univ_page_size, IBUF_BITMAP_IBUF, FALSE,
 		&mtr);
 
 	ut_d(buf_page_set_file_page_was_freed(page_id));
diff --git a/storage/innobase/include/fil0fil.h b/storage/innobase/include/fil0fil.h
index 96fe6b7e5f3..a78eb5debb1 100644
--- a/storage/innobase/include/fil0fil.h
+++ b/storage/innobase/include/fil0fil.h
@@ -204,6 +204,12 @@ struct fil_space_t {
 		return !atomic_write_supported
 			&& srv_use_doublewrite_buf && buf_dblwr;
 	}
+
+	/** Open each file. Only invoked on fil_system.temp_space.
+	@return whether all files were opened */
+	bool open();
+	/** Close each file. Only invoked on fil_system.temp_space. */
+	void close();
 };
 
 /** Value of fil_space_t::magic_n */
@@ -517,6 +523,8 @@ private:
   bool m_initialised;
 public:
 	ib_mutex_t	mutex;		/*!< The mutex protecting the cache */
+	fil_space_t*	sys_space;	/*!< The innodb_system tablespace */
+	fil_space_t*	temp_space;	/*!< The innodb_temporary tablespace */
 	hash_table_t*	spaces;		/*!< The hash table of spaces in the
 					system; they are hashed on the space
 					id */
@@ -580,13 +588,6 @@ fil_space_get_latch(
 	ulint	id,
 	ulint*	flags);
 
-/** Gets the type of a file space.
-@param[in]	id	tablespace identifier
-@return file type */
-fil_type_t
-fil_space_get_type(
-	ulint	id);
-
 /** Note that a tablespace has been imported.
 It is initially marked as FIL_TYPE_IMPORT so that no logging is
 done during the import process when the space ID is stamped to each page.
@@ -691,19 +692,6 @@ fil_space_get_flags(
 /*================*/
 	ulint	id);	/*!< in: space id */
 
-/** Open each fil_node_t of a named fil_space_t if not already open.
-@param[in]	name	Tablespace name
-@return true if all file nodes are opened. */
-bool
-fil_space_open(
-	const char*	name);
-
-/** Close each fil_node_t of a named fil_space_t if open.
-@param[in]	name	Tablespace name */
-void
-fil_space_close(
-	const char*	name);
-
 /** Returns the page size of the space and whether it is compressed or not.
 The tablespace must be cached in the memory cache.
 @param[in]	id	space id
@@ -1235,13 +1223,6 @@ fil_space_release_free_extents(
 /*===========================*/
 	ulint	id,		/*!< in: space id */
 	ulint	n_reserved);	/*!< in: how many one reserved */
-/*******************************************************************//**
-Gets the number of reserved extents. If the database is silent, this number
-should be zero. */
-ulint
-fil_space_get_n_reserved_extents(
-/*=============================*/
-	ulint	id);		/*!< in: space id */
 
 /** Reads or writes data. This operation could be asynchronous (aio).
 
diff --git a/storage/innobase/include/fsp0fsp.h b/storage/innobase/include/fsp0fsp.h
index e0999c84ee9..9dafd5cdc3a 100644
--- a/storage/innobase/include/fsp0fsp.h
+++ b/storage/innobase/include/fsp0fsp.h
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2013, 2017, MariaDB Corporation.
+Copyright (c) 2013, 2018, 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
@@ -294,16 +294,6 @@ the extent are free and which contain old tuple version to clean. */
 #ifndef UNIV_INNOCHECKSUM
 /* @} */
 
-/**********************************************************************//**
-Gets the size of the system tablespace from the tablespace header.  If
-we do not have an auto-extending data file, this should be equal to
-the size of the data files.  If there is an auto-extending data file,
-this can be smaller.
-@return size in pages */
-ulint
-fsp_header_get_tablespace_size(void);
-/*================================*/
-
 /** Calculate the number of pages to extend a datafile.
 We extend single-table tablespaces first one extent at a time,
 but 4 at a time for bigger tablespaces. It is not enough to extend always
@@ -398,14 +388,6 @@ void
 fsp_header_init(ulint space_id, ulint size, mtr_t* mtr);
 
 /**********************************************************************//**
-Increases the space size field of a space. */
-void
-fsp_header_inc_size(
-/*================*/
-	ulint	space_id,	/*!< in: space id */
-	ulint	size_inc,	/*!< in: size increment in pages */
-	mtr_t*	mtr);		/*!< in/out: mini-transaction */
-/**********************************************************************//**
 Creates a new segment.
 @return the block where the segment header is placed, x-latched, NULL
 if could not create segment because of lack of space */
diff --git a/storage/innobase/include/mtr0mtr.h b/storage/innobase/include/mtr0mtr.h
index 6639a3448ea..20d9d2066a0 100644
--- a/storage/innobase/include/mtr0mtr.h
+++ b/storage/innobase/include/mtr0mtr.h
@@ -29,9 +29,7 @@ Created 11/26/1995 Heikki Tuuri
 #define mtr0mtr_h
 
 #include "univ.i"
-#include "log0types.h"
-#include "mtr0types.h"
-#include "buf0types.h"
+#include "fil0fil.h"
 #include "dyn0buf.h"
 
 /** Start a mini-transaction. */
@@ -140,9 +138,6 @@ savepoint. */
 @return true if the mtr is dirtying a clean page. */
 #define mtr_block_dirtied(b)	mtr_t::is_block_dirtied((b))
 
-/** Forward declaration of a tablespace object */
-struct fil_space_t;
-
 /** Append records to the system-wide redo log buffer.
 @param[in]	log	redo log records */
 void
@@ -194,12 +189,6 @@ struct mtr_t {
 		/** User tablespace that is being modified by the
 		mini-transaction */
 		fil_space_t*	m_user_space;
-		/** Undo tablespace that is being modified by the
-		mini-transaction */
-		fil_space_t*	m_undo_space;
-		/** System tablespace if it is being modified by the
-		mini-transaction */
-		fil_space_t*	m_sys_space;
 
 		/** State of the transaction */
 		mtr_state_t	m_state;
@@ -302,17 +291,6 @@ struct mtr_t {
 	@return	old mode */
 	inline mtr_log_t set_log_mode(mtr_log_t mode);
 
-	/** Note that the mini-transaction is modifying the system tablespace
-	(for example, for the change buffer or for undo logs)
-	@return the system tablespace */
-	fil_space_t* set_sys_modified()
-	{
-		if (!m_impl.m_sys_space) {
-			lookup_sys_space();
-		}
-		return(m_impl.m_sys_space);
-	}
-
 	/** Copy the tablespaces associated with the mini-transaction
 	(needed for generating MLOG_FILE_NAME records)
 	@param[in]	mtr	mini-transaction that may modify
@@ -321,13 +299,9 @@ struct mtr_t {
 	{
 		ut_ad(!m_impl.m_user_space_id);
 		ut_ad(!m_impl.m_user_space);
-		ut_ad(!m_impl.m_undo_space);
-		ut_ad(!m_impl.m_sys_space);
 
 		ut_d(m_impl.m_user_space_id = mtr.m_impl.m_user_space_id);
 		m_impl.m_user_space = mtr.m_impl.m_user_space;
-		m_impl.m_undo_space = mtr.m_impl.m_undo_space;
-		m_impl.m_sys_space = mtr.m_impl.m_sys_space;
 	}
 
 	/** Set the tablespace associated with the mini-transaction
@@ -339,17 +313,27 @@ struct mtr_t {
 		ut_ad(!m_impl.m_user_space_id);
 		ut_d(m_impl.m_user_space_id = space_id);
 		if (!space_id) {
-			return(set_sys_modified());
+			return fil_system.sys_space;
 		} else {
-			lookup_user_space(space_id);
-			return(m_impl.m_user_space);
+			ut_ad(m_impl.m_user_space_id == space_id);
+			ut_ad(!m_impl.m_user_space);
+			m_impl.m_user_space = fil_space_get(space_id);
+			ut_ad(m_impl.m_user_space);
+			return m_impl.m_user_space;
 		}
 	}
 
 	/** Set the tablespace associated with the mini-transaction
 	(needed for generating a MLOG_FILE_NAME record)
 	@param[in]	space	user or system tablespace */
-	void set_named_space(fil_space_t* space);
+	void set_named_space(fil_space_t* space)
+	{
+		ut_ad(m_impl.m_user_space_id == TRX_SYS_SPACE);
+		ut_d(m_impl.m_user_space_id = space->id);
+		if (space->id != TRX_SYS_SPACE) {
+			m_impl.m_user_space = space;
+		}
+	}
 
 #ifdef UNIV_DEBUG
 	/** Check the tablespace associated with the mini-transaction
@@ -582,12 +566,6 @@ struct mtr_t {
 		MY_ATTRIBUTE((warn_unused_result));
 
 private:
-	/** Look up the system tablespace. */
-	void lookup_sys_space();
-	/** Look up the user tablespace.
-	@param[in]	space_id	tablespace ID  */
-	void lookup_user_space(ulint space_id);
-
 	class Command;
 
 	friend class Command;
diff --git a/storage/innobase/mtr/mtr0mtr.cc b/storage/innobase/mtr/mtr0mtr.cc
index 72b24b08871..7926ac312ef 100644
--- a/storage/innobase/mtr/mtr0mtr.cc
+++ b/storage/innobase/mtr/mtr0mtr.cc
@@ -514,8 +514,6 @@ mtr_t::start(bool sync, bool read_only)
 	m_impl.m_state = MTR_STATE_ACTIVE;
 	ut_d(m_impl.m_user_space_id = TRX_SYS_SPACE);
 	m_impl.m_user_space = NULL;
-	m_impl.m_undo_space = NULL;
-	m_impl.m_sys_space = NULL;
 	m_impl.m_flush_observer = NULL;
 
 	ut_d(m_impl.m_magic_n = MTR_MAGIC_N);
@@ -638,18 +636,8 @@ mtr_t::commit_checkpoint(
 bool
 mtr_t::is_named_space(ulint space) const
 {
-	ut_ad(!m_impl.m_sys_space
-	      || m_impl.m_sys_space->id == TRX_SYS_SPACE);
-	ut_ad(!m_impl.m_undo_space
-	      || m_impl.m_undo_space->id != TRX_SYS_SPACE);
 	ut_ad(!m_impl.m_user_space
 	      || m_impl.m_user_space->id != TRX_SYS_SPACE);
-	ut_ad(!m_impl.m_sys_space
-	      || m_impl.m_sys_space != m_impl.m_user_space);
-	ut_ad(!m_impl.m_sys_space
-	      || m_impl.m_sys_space != m_impl.m_undo_space);
-	ut_ad(!m_impl.m_user_space
-	      || m_impl.m_user_space != m_impl.m_undo_space);
 
 	switch (get_log_mode()) {
 	case MTR_LOG_NONE:
@@ -681,22 +669,15 @@ mtr_t::x_lock_space(ulint space_id, const char* file, unsigned line)
 	ut_ad(is_active());
 
 	if (space_id == TRX_SYS_SPACE) {
-		space = m_impl.m_sys_space;
-
-		if (!space) {
-			space = m_impl.m_sys_space = fil_space_get(space_id);
-		}
+		space = fil_system.sys_space;
 	} else if ((space = m_impl.m_user_space) && space_id == space->id) {
-	} else if ((space = m_impl.m_undo_space) && space_id == space->id) {
-	} else if (get_log_mode() == MTR_LOG_NO_REDO) {
+	} else {
 		space = fil_space_get(space_id);
-		ut_ad(space->purpose == FIL_TYPE_TEMPORARY
+		ut_ad(get_log_mode() != MTR_LOG_NO_REDO
+		      || space->purpose == FIL_TYPE_TEMPORARY
 		      || space->purpose == FIL_TYPE_IMPORT
 		      || space->redo_skipped_count > 0
 		      || srv_is_tablespace_truncated(space->id));
-	} else {
-		/* called from trx_rseg_create() */
-		space = m_impl.m_undo_space = fil_space_get(space_id);
 	}
 
 	ut_ad(space);
@@ -708,44 +689,6 @@ mtr_t::x_lock_space(ulint space_id, const char* file, unsigned line)
 	return(space);
 }
 
-/** Look up the system tablespace. */
-void
-mtr_t::lookup_sys_space()
-{
-	ut_ad(!m_impl.m_sys_space);
-	m_impl.m_sys_space = fil_space_get(TRX_SYS_SPACE);
-	ut_ad(m_impl.m_sys_space);
-}
-
-/** Look up the user tablespace.
-@param[in]	space_id	tablespace ID */
-void
-mtr_t::lookup_user_space(ulint space_id)
-{
-	ut_ad(space_id != TRX_SYS_SPACE);
-	ut_ad(m_impl.m_user_space_id == space_id);
-	ut_ad(!m_impl.m_user_space);
-	m_impl.m_user_space = fil_space_get(space_id);
-	ut_ad(m_impl.m_user_space);
-}
-
-/** Set the tablespace associated with the mini-transaction
-(needed for generating a MLOG_FILE_NAME record)
-@param[in]	space	user or system tablespace */
-void
-mtr_t::set_named_space(fil_space_t* space)
-{
-	ut_ad(m_impl.m_user_space_id == TRX_SYS_SPACE);
-	ut_d(m_impl.m_user_space_id = space->id);
-	if (space->id == TRX_SYS_SPACE) {
-		ut_ad(m_impl.m_sys_space == NULL
-		      || m_impl.m_sys_space == space);
-		m_impl.m_sys_space = space;
-	} else {
-		m_impl.m_user_space = space;
-	}
-}
-
 /** Release an object in the memo stack.
 @return true if released */
 bool
@@ -985,25 +928,16 @@ mtr_t::release_free_extents(ulint n_reserved)
 {
 	fil_space_t*	space;
 
-	ut_ad(m_impl.m_undo_space == NULL);
-
 	if (m_impl.m_user_space != NULL) {
-
 		ut_ad(m_impl.m_user_space->id
 		      == m_impl.m_user_space_id);
-		ut_ad(memo_contains(get_memo(), &m_impl.m_user_space->latch,
-				    MTR_MEMO_X_LOCK));
-
 		space = m_impl.m_user_space;
 	} else {
-
-		ut_ad(m_impl.m_sys_space->id == TRX_SYS_SPACE);
-		ut_ad(memo_contains(get_memo(), &m_impl.m_sys_space->latch,
-				    MTR_MEMO_X_LOCK));
-
-		space = m_impl.m_sys_space;
+		space = fil_system.sys_space;
 	}
 
+	ut_ad(memo_contains(get_memo(), &space->latch, MTR_MEMO_X_LOCK));
+
 	space->release_free_extents(n_reserved);
 }
 
diff --git a/storage/innobase/srv/srv0srv.cc b/storage/innobase/srv/srv0srv.cc
index fef5ed3e37b..ce19cdd0817 100644
--- a/storage/innobase/srv/srv0srv.cc
+++ b/storage/innobase/srv/srv0srv.cc
@@ -1204,7 +1204,6 @@ srv_printf_innodb_monitor(
 {
 	double	time_elapsed;
 	time_t	current_time;
-	ulint	n_reserved;
 	ibool	ret;
 
 	mutex_enter(&srv_innodb_monitor_mutex);
@@ -1367,8 +1366,7 @@ srv_printf_innodb_monitor(
 	fprintf(file, ULINTPF " read views open inside InnoDB\n",
 		trx_sys.view_count());
 
-	n_reserved = fil_space_get_n_reserved_extents(0);
-	if (n_reserved > 0) {
+	if (ulint n_reserved = fil_system.sys_space->n_reserved_extents) {
 		fprintf(file,
 			ULINTPF " tablespace extents now reserved for"
 			" B-tree split operations\n",
diff --git a/storage/innobase/srv/srv0start.cc b/storage/innobase/srv/srv0start.cc
index 866aa6990d1..af60e846c7e 100644
--- a/storage/innobase/srv/srv0start.cc
+++ b/storage/innobase/srv/srv0start.cc
@@ -1173,47 +1173,30 @@ srv_open_tmp_tablespace(bool create_new_db)
 		&create_new_temp_space, 12 * 1024 * 1024);
 
 	if (err == DB_FAIL) {
-
-		ib::error() << "The " << srv_tmp_space.name()
-			<< " data file must be writable!";
-
+		ib::error() << "The innodb_temporary"
+			" data file must be writable!";
 		err = DB_ERROR;
-
 	} else if (err != DB_SUCCESS) {
-		ib::error() << "Could not create the shared "
-			<< srv_tmp_space.name() << ".";
-
+		ib::error() << "Could not create the shared innodb_temporary.";
 	} else if ((err = srv_tmp_space.open_or_create(
 			    true, create_new_db, &sum_of_new_sizes, NULL))
 		   != DB_SUCCESS) {
-
-		ib::error() << "Unable to create the shared "
-			<< srv_tmp_space.name();
-
+		ib::error() << "Unable to create the shared innodb_temporary";
+	} else if (fil_system.temp_space->open()) {
+		/* Initialize the header page */
+		mtr_t mtr;
+		mtr.start();
+		mtr.set_log_mode(MTR_LOG_NO_REDO);
+		fsp_header_init(SRV_TMP_SPACE_ID,
+				srv_tmp_space.get_sum_of_sizes(),
+				&mtr);
+		mtr.commit();
 	} else {
-
-		mtr_t	mtr;
-		ulint	size = srv_tmp_space.get_sum_of_sizes();
-
-		/* Open this shared temp tablespace in the fil_system so that
-		it stays open until shutdown. */
-		if (fil_space_open(srv_tmp_space.name())) {
-
-			/* Initialize the header page */
-			mtr_start(&mtr);
-			mtr_set_log_mode(&mtr, MTR_LOG_NO_REDO);
-
-			fsp_header_init(SRV_TMP_SPACE_ID, size, &mtr);
-
-			mtr_commit(&mtr);
-		} else {
-			/* This file was just opened in the code above! */
-			ib::error() << "The " << srv_tmp_space.name()
-				<< " data file cannot be re-opened"
-				" after check_file_spec() succeeded!";
-
-			err = DB_ERROR;
-		}
+		/* This file was just opened in the code above! */
+		ib::error() << "The innodb_temporary"
+			" data file cannot be re-opened"
+			" after check_file_spec() succeeded!";
+		err = DB_ERROR;
 	}
 
 	return(err);
@@ -2121,7 +2104,7 @@ files_checked:
 	shutdown */
 
 	fil_open_log_and_system_tablespace_files();
-	ut_d(fil_space_get(0)->recv_size = srv_sys_space_size_debug);
+	ut_d(fil_system.sys_space->recv_size = srv_sys_space_size_debug);
 
 	err = srv_undo_tablespaces_init(create_new_db);
 
@@ -2269,7 +2252,19 @@ files_checked:
 			if (sum_of_new_sizes > 0) {
 				/* New data file(s) were added */
 				mtr.start();
-				fsp_header_inc_size(0, sum_of_new_sizes, &mtr);
+				buf_block_t* block = buf_page_get(
+					page_id_t(0, 0), univ_page_size,
+					RW_SX_LATCH, &mtr);
+				ulint size = mach_read_from_4(
+					FSP_HEADER_OFFSET + FSP_SIZE
+					+ block->frame);
+				ut_ad(size == fil_system.sys_space
+				      ->size_in_header);
+				size += sum_of_new_sizes;
+				mlog_write_ulint(FSP_HEADER_OFFSET + FSP_SIZE
+						 + block->frame, size,
+						 MLOG_4BYTES, &mtr);
+				fil_system.sys_space->size_in_header = size;
 				mtr.commit();
 				/* Immediately write the log record about
 				increased tablespace size to disk, so that it
@@ -2279,8 +2274,20 @@ files_checked:
 			}
 		}
 
+#ifdef UNIV_DEBUG
+		{
+			mtr.start();
+			buf_block_t* block = buf_page_get(page_id_t(0, 0),
+							  univ_page_size,
+							  RW_S_LATCH, &mtr);
+			ut_ad(mach_read_from_4(FSP_SIZE + FSP_HEADER_OFFSET
+					       + block->frame)
+			      == fil_system.sys_space->size_in_header);
+			mtr.commit();
+		}
+#endif
 		const ulint	tablespace_size_in_header
-			= fsp_header_get_tablespace_size();
+			= fil_system.sys_space->size_in_header;
 		const ulint	sum_of_data_file_sizes
 			= srv_sys_space.get_sum_of_sizes();
 		/* Compare the system tablespace file size to what is
@@ -2430,10 +2437,8 @@ files_checked:
 		/* Validate a few system page types that were left
 		uninitialized by older versions of MySQL. */
 		if (!high_level_read_only) {
-			mtr_t		mtr;
 			buf_block_t*	block;
 			mtr.start();
-			mtr.set_sys_modified();
 			/* Bitmap page types will be reset in
 			buf_dblwr_check_block() without redo logging. */
 			block = buf_page_get(
diff --git a/storage/innobase/trx/trx0rseg.cc b/storage/innobase/trx/trx0rseg.cc
index 9a2d1d97875..c12f9b319fa 100644
--- a/storage/innobase/trx/trx0rseg.cc
+++ b/storage/innobase/trx/trx0rseg.cc
@@ -640,11 +640,7 @@ trx_temp_rseg_create()
 	for (ulong i = 0; i < TRX_SYS_N_RSEGS; i++) {
 		mtr.start();
 		mtr.set_log_mode(MTR_LOG_NO_REDO);
-#ifdef UNIV_DEBUG
-		const fil_space_t*	space =
-#endif /* UNIV_DEBUG */
-			mtr_x_lock_space(SRV_TMP_SPACE_ID, &mtr);
-		ut_ad(space->purpose == FIL_TYPE_TEMPORARY);
+		mtr_x_lock(&fil_system.temp_space->latch, &mtr);
 
 		ulint page_no = trx_rseg_header_create(
 			SRV_TMP_SPACE_ID, i, NULL, &mtr);
diff --git a/storage/innobase/trx/trx0sys.cc b/storage/innobase/trx/trx0sys.cc
index 13ebe27f539..4d4f8e2e83d 100644
--- a/storage/innobase/trx/trx0sys.cc
+++ b/storage/innobase/trx/trx0sys.cc
@@ -162,7 +162,7 @@ trx_sysf_create(
 	then enter the kernel: we must do it in this order to conform
 	to the latching order rules. */
 
-	mtr_x_lock_space(TRX_SYS_SPACE, mtr);
+	mtr_x_lock(&fil_system.sys_space->latch, 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,