示例#1
0
/****************************************************************//**
Creates a rollback segment header. This function is called only when
a new rollback segment is created in the database.
@return	page number of the created segment, FIL_NULL if fail */
UNIV_INTERN
ulint
trx_rseg_header_create(
/*===================*/
	ulint	space,		/*!< in: space id */
	ulint	zip_size,	/*!< in: compressed page size in bytes
				or 0 for uncompressed pages */
	ulint	max_size,	/*!< in: max size in pages */
	ulint	rseg_slot_no,	/*!< in: rseg id == slot number in trx sys */
	mtr_t*	mtr)		/*!< in: mtr */
{
	ulint		page_no;
	trx_rsegf_t*	rsegf;
	trx_sysf_t*	sys_header;
	ulint		i;
	buf_block_t*	block;

	ut_ad(mtr);
	ut_ad(mutex_own(&kernel_mutex));
	ut_ad(mtr_memo_contains(mtr, fil_space_get_latch(space, NULL),
				MTR_MEMO_X_LOCK));

	/* Allocate a new file segment for the rollback segment */
	block = fseg_create(space, 0,
			    TRX_RSEG + TRX_RSEG_FSEG_HEADER, mtr);

	if (block == NULL) {
		/* No space left */

		return(FIL_NULL);
	}

	buf_block_dbg_add_level(block, SYNC_RSEG_HEADER_NEW);

	page_no = buf_block_get_page_no(block);

	/* Get the rollback segment file page */
	rsegf = trx_rsegf_get_new(space, zip_size, page_no, mtr);

	/* Initialize max size field */
	mlog_write_ulint(rsegf + TRX_RSEG_MAX_SIZE, max_size,
			 MLOG_4BYTES, mtr);

	/* Initialize the history list */

	mlog_write_ulint(rsegf + TRX_RSEG_HISTORY_SIZE, 0, MLOG_4BYTES, mtr);
	flst_init(rsegf + TRX_RSEG_HISTORY, mtr);

	/* Reset the undo log slots */
	for (i = 0; i < TRX_RSEG_N_SLOTS; i++) {

		trx_rsegf_set_nth_undo(rsegf, i, FIL_NULL, mtr);
	}

	/* Add the rollback segment info to the free slot in
	the trx system header */

	sys_header = trx_sysf_get(mtr);

	trx_sysf_rseg_set_space(sys_header, rseg_slot_no, space, mtr);
	trx_sysf_rseg_set_page_no(sys_header, rseg_slot_no, page_no, mtr);

	return(page_no);
}
示例#2
0
文件: trx0rseg.c 项目: isleon/Jaxer
ulint
trx_rseg_header_create(
/*===================*/
				/* out: page number of the created segment,
				FIL_NULL if fail */
	ulint	space,		/* in: space id */
	ulint	max_size,	/* in: max size in pages */
	ulint*	slot_no,	/* out: rseg id == slot number in trx sys */
	mtr_t*	mtr)		/* in: mtr */
{
	ulint		page_no;
	trx_rsegf_t*	rsegf;
	trx_sysf_t*	sys_header;
	ulint		i;
	page_t*		page;
	
	ut_ad(mtr);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&kernel_mutex));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(mtr_memo_contains(mtr, fil_space_get_latch(space),
							MTR_MEMO_X_LOCK));
	sys_header = trx_sysf_get(mtr);

	*slot_no = trx_sysf_rseg_find_free(mtr);

	if (*slot_no == ULINT_UNDEFINED) {

		return(FIL_NULL);
	}

	/* Allocate a new file segment for the rollback segment */
	page = fseg_create(space, 0, TRX_RSEG + TRX_RSEG_FSEG_HEADER, mtr);

	if (page == NULL) {
		/* No space left */

		return(FIL_NULL);
	}

#ifdef UNIV_SYNC_DEBUG
	buf_page_dbg_add_level(page, SYNC_RSEG_HEADER_NEW);
#endif /* UNIV_SYNC_DEBUG */

	page_no = buf_frame_get_page_no(page);

	/* Get the rollback segment file page */
	rsegf = trx_rsegf_get_new(space, page_no, mtr);
					    
	/* Initialize max size field */
	mlog_write_ulint(rsegf + TRX_RSEG_MAX_SIZE, max_size, MLOG_4BYTES, mtr);
	
	/* Initialize the history list */

	mlog_write_ulint(rsegf + TRX_RSEG_HISTORY_SIZE, 0, MLOG_4BYTES, mtr);
	flst_init(rsegf + TRX_RSEG_HISTORY, mtr);

	/* Reset the undo log slots */
	for (i = 0; i < TRX_RSEG_N_SLOTS; i++) {

		trx_rsegf_set_nth_undo(rsegf, i, FIL_NULL, mtr);
	}

	/* Add the rollback segment info to the free slot in the trx system
	header */

	trx_sysf_rseg_set_space(sys_header, *slot_no, space, mtr);	
	trx_sysf_rseg_set_page_no(sys_header, *slot_no, page_no, mtr);

	return(page_no);
}