/*****************************************************************************

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Copyright (c) 2017, 2020, MariaDB Corporation.

This program is free software; you can redistribute it and/or modify it under
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FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

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this program; if not, write to the Free Software Foundation, Inc.,
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*****************************************************************************/

/**************************************************//**
@file include/trx0rseg.ic
Rollback segment

Created 3/26/1996 Heikki Tuuri
*******************************************************/

#include "srv0srv.h"
#include "mtr0log.h"

/** Gets a rollback segment header.
@param[in]	space		space where placed
@param[in]	page_no		page number of the header
@param[in,out]	mtr		mini-transaction
@return rollback segment header, page x-latched */
UNIV_INLINE
buf_block_t*
trx_rsegf_get(fil_space_t* space, uint32_t page_no, mtr_t* mtr)
{
	ut_ad(space == fil_system.sys_space || space == fil_system.temp_space
	      || srv_is_undo_tablespace(space->id)
	      || !srv_was_started);

	return buf_page_get(page_id_t(space->id, page_no),
			    0, RW_X_LATCH, mtr);
}

/** Gets a newly created rollback segment header.
@param[in]	space		space where placed
@param[in]	page_no		page number of the header
@param[in,out]	mtr		mini-transaction
@return rollback segment header, page x-latched */
UNIV_INLINE
buf_block_t*
trx_rsegf_get_new(
	ulint			space,
	uint32_t		page_no,
	mtr_t*			mtr)
{
	ut_ad(space <= srv_undo_tablespaces_active || space == SRV_TMP_SPACE_ID
	      || !srv_was_started);
	ut_ad(space <= TRX_SYS_MAX_UNDO_SPACES || space == SRV_TMP_SPACE_ID);

	return buf_page_get(page_id_t(space, page_no), 0, RW_X_LATCH, mtr);
}