MDEV-24626 fixup: Remove useless code

fil_ibd_create(): Remove code that should have been removed in
commit 86dc7b4 already.
We no longer wrote an initialized page to the file, but we would
still allocate a page image in memory and write it.

xb_space_create_file(): Remove an unnecessary page write.
(This is a functional change for Mariabackup.)

extra/mariabackup/xtrabackup.cc

@@ -4909,53 +4909,6 @@ xb_space_create_file(
 		return ret;
 	}
 
-	/* Align the memory for file i/o if we might have O_DIRECT set */
-	byte* page = static_cast<byte*>(aligned_malloc(2 * srv_page_size,
-						       srv_page_size));
-
-	memset(page, '\0', srv_page_size);
-
-	fsp_header_init_fields(page, space_id, flags);
-	mach_write_to_4(page + FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID, space_id);
-
-	const ulint zip_size = fil_space_t::zip_size(flags);
-
-	if (!zip_size) {
-		buf_flush_init_for_writing(
-			NULL, page, NULL,
-			fil_space_t::full_crc32(flags));
-
-		ret = os_file_write(IORequestWrite, path, *file, page, 0,
-				    srv_page_size);
-	} else {
-		page_zip_des_t	page_zip;
-		page_zip_set_size(&page_zip, zip_size);
-		page_zip.data = page + srv_page_size;
-		fprintf(stderr, "zip_size = " ULINTPF "\n", zip_size);
-
-#ifdef UNIV_DEBUG
-		page_zip.m_start = 0;
-#endif /* UNIV_DEBUG */
-		page_zip.m_end = 0;
-		page_zip.m_nonempty = 0;
-		page_zip.n_blobs = 0;
-
-		buf_flush_init_for_writing(NULL, page, &page_zip, false);
-
-		ret = os_file_write(IORequestWrite, path, *file,
-				    page_zip.data, 0, zip_size);
-	}
-
-	aligned_free(page);
-
-	if (ret != DB_SUCCESS) {
-		msg("mariabackup: could not write the first page to %s",
-		    path);
-		os_file_close(*file);
-		os_file_delete(0, path);
-		return ret;
-	}
-
 	return TRUE;
 }
 

storage/innobase/fil/fil0crypt.cc

@@ -372,33 +372,6 @@ void fil_crypt_parse(fil_space_t* space, const byte* data)
 	}
 }
 
-/** Fill crypt data information to the give page.
-It should be called during ibd file creation.
-@param[in]	flags	tablespace flags
-@param[in,out]	page	first page of the tablespace */
-void
-fil_space_crypt_t::fill_page0(
-	ulint	flags,
-	byte*	page)
-{
-	const uint len = sizeof(iv);
-	const ulint offset = FSP_HEADER_OFFSET
-		+ fsp_header_get_encryption_offset(
-			fil_space_t::zip_size(flags));
-
-	memcpy(page + offset, CRYPT_MAGIC, MAGIC_SZ);
-	mach_write_to_1(page + offset + MAGIC_SZ, type);
-	mach_write_to_1(page + offset + MAGIC_SZ + 1, len);
-	memcpy(page + offset + MAGIC_SZ + 2, &iv, len);
-
-	mach_write_to_4(page + offset + MAGIC_SZ + 2 + len,
-			min_key_version);
-	mach_write_to_4(page + offset + MAGIC_SZ + 2 + len + 4,
-			key_id);
-	mach_write_to_1(page + offset + MAGIC_SZ + 2  + len + 8,
-			encryption);
-}
-
 /** Write encryption metadata to the first page.
 @param[in,out]	block	first page of the tablespace
 @param[in,out]	mtr	mini-transaction */

storage/innobase/fil/fil0fil.cc

@@ -1962,7 +1962,6 @@ fil_ibd_create(
 	dberr_t*	err)
 {
 	pfs_os_file_t	file;
-	byte*		page;
 	bool		success;
 	mtr_t		mtr;
 	bool		has_data_dir = FSP_FLAGS_HAS_DATA_DIR(flags) != 0;
@@ -2043,43 +2042,18 @@ fil_ibd_create(
 		return NULL;
 	}
 
-	/* We have to write the space id to the file immediately and flush the
-	file to disk. This is because in crash recovery we must be aware what
-	tablespaces exist and what are their space id's, so that we can apply
-	the log records to the right file. It may take quite a while until
-	buffer pool flush algorithms write anything to the file and flush it to
-	disk. If we would not write here anything, the file would be filled
-	with zeros from the call of os_file_set_size(), until a buffer pool
-	flush would write to it. */
-
-	/* Align the memory for file i/o if we might have O_DIRECT set */
-	page = static_cast<byte*>(aligned_malloc(2 * srv_page_size,
-						 srv_page_size));
-
-	memset(page, '\0', srv_page_size);
-
 	if (fil_space_t::full_crc32(flags)) {
 		flags |= FSP_FLAGS_FCRC32_PAGE_SSIZE();
 	} else {
 		flags |= FSP_FLAGS_PAGE_SSIZE();
 	}
 
-	fsp_header_init_fields(page, space_id, flags);
-	mach_write_to_4(page + FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID, space_id);
-
 	/* Create crypt data if the tablespace is either encrypted or user has
 	requested it to remain unencrypted. */
 	crypt_data = (mode != FIL_ENCRYPTION_DEFAULT || srv_encrypt_tables)
 		? fil_space_create_crypt_data(mode, key_id)
 		: NULL;
 
-	if (crypt_data) {
-		/* Write crypt data information in page0 while creating
-		ibd file. */
-		crypt_data->fill_page0(flags, page);
-	}
-
-	aligned_free(page);
 	fil_space_t::name_type space_name;
 
 	if (has_data_dir) {

storage/innobase/fsp/fsp0fsp.cc

@@ -525,26 +525,6 @@ void fil_space_t::modify_check(const mtr_t& mtr) const
 }
 #endif
 
-/**********************************************************************//**
-Writes the space id and flags to a tablespace header.  The flags contain
-row type, physical/compressed page size, and logical/uncompressed page
-size of the tablespace. */
-void
-fsp_header_init_fields(
-/*===================*/
-	page_t*	page,		/*!< in/out: first page in the space */
-	ulint	space_id,	/*!< in: space id */
-	ulint	flags)		/*!< in: tablespace flags (FSP_SPACE_FLAGS) */
-{
-	flags &= ~FSP_FLAGS_MEM_MASK;
-	ut_a(fil_space_t::is_valid_flags(flags, space_id));
-
-	mach_write_to_4(FSP_HEADER_OFFSET + FSP_SPACE_ID + page,
-			space_id);
-	mach_write_to_4(FSP_HEADER_OFFSET + FSP_SPACE_FLAGS + page,
-			flags);
-}
-
 /** Initialize a tablespace header.
 @param[in,out]	space	tablespace
 @param[in]	size	current size in blocks

storage/innobase/include/fil0crypt.h

@@ -172,12 +172,6 @@ struct fil_space_crypt_t : st_encryption_scheme
 		return (encryption == FIL_ENCRYPTION_OFF);
 	}
 
-	/** Fill crypt data information to the give page.
-	It should be called during ibd file creation.
-	@param[in]	flags	tablespace flags
-	@param[in,out]	page	first page of the tablespace */
-	void fill_page0(ulint flags, byte* page);
-
 	/** Write encryption metadata to the first page.
 	@param[in,out]	block	first page of the tablespace
 	@param[in,out]	mtr	mini-transaction */

storage/innobase/include/fsp0fsp.h

@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2013, 2020, MariaDB Corporation.
+Copyright (c) 2013, 2021, 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
@@ -342,17 +342,6 @@ fsp_header_check_encryption_key(
 	ulint			fsp_flags,
 	page_t*			page);
 
-/**********************************************************************//**
-Writes the space id and flags to a tablespace header.  The flags contain
-row type, physical/compressed page size, and logical/uncompressed page
-size of the tablespace. */
-void
-fsp_header_init_fields(
-/*===================*/
-	page_t*	page,		/*!< in/out: first page in the space */
-	ulint	space_id,	/*!< in: space id */
-	ulint	flags);		/*!< in: tablespace flags (FSP_SPACE_FLAGS):
-				0, or table->flags if newer than COMPACT */
 /** Initialize a tablespace header.
 @param[in,out]	space	tablespace
 @param[in]	size	current size in blocks