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Diffstat (limited to 'storage/innobase/include/trx0undo.inl')
| -rw-r--r-- | storage/innobase/include/trx0undo.inl | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/storage/innobase/include/trx0undo.inl b/storage/innobase/include/trx0undo.inl new file mode 100644 index 00000000000..1a9c7774580 --- /dev/null +++ b/storage/innobase/include/trx0undo.inl @@ -0,0 +1,151 @@ +/***************************************************************************** + +Copyright (c) 1996, 2013, Oracle and/or its affiliates. All Rights Reserved. +Copyright (c) 2017, 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 +Foundation; version 2 of the License. + +This program is distributed in the hope that it will be useful, but WITHOUT +ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. + +You should have received a copy of the GNU General Public License along with +this program; if not, write to the Free Software Foundation, Inc., +51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA + +*****************************************************************************/ + +/**************************************************//** +@file include/trx0undo.ic +Transaction undo log + +Created 3/26/1996 Heikki Tuuri +*******************************************************/ + +#include "data0type.h" +#include "page0page.h" + +/***********************************************************************//** +Builds a roll pointer. +@return roll pointer */ +UNIV_INLINE +roll_ptr_t +trx_undo_build_roll_ptr( +/*====================*/ + bool is_insert, /*!< in: TRUE if insert undo log */ + ulint rseg_id, /*!< in: rollback segment id */ + uint32_t page_no, /*!< in: page number */ + uint16_t offset) /*!< in: offset of the undo entry within page */ +{ + compile_time_assert(DATA_ROLL_PTR_LEN == 7); + ut_ad(rseg_id < TRX_SYS_N_RSEGS); + + return roll_ptr_t{is_insert} << ROLL_PTR_INSERT_FLAG_POS | + roll_ptr_t{rseg_id} << ROLL_PTR_RSEG_ID_POS | + roll_ptr_t{page_no} << ROLL_PTR_PAGE_POS | offset; +} + +/***********************************************************************//** +Decodes a roll pointer. */ +UNIV_INLINE +void +trx_undo_decode_roll_ptr( +/*=====================*/ + roll_ptr_t roll_ptr, /*!< in: roll pointer */ + bool* is_insert, /*!< out: TRUE if insert undo log */ + ulint* rseg_id, /*!< out: rollback segment id */ + uint32_t* page_no, /*!< out: page number */ + uint16_t* offset) /*!< out: offset of the undo + entry within page */ +{ + compile_time_assert(DATA_ROLL_PTR_LEN == 7); + ut_ad(roll_ptr < (1ULL << 56)); + *offset= static_cast<uint16_t>(roll_ptr); + *page_no= static_cast<uint32_t>(roll_ptr >> 16); + *rseg_id= static_cast<ulint>(roll_ptr >> 48 & 0x7F); + *is_insert= static_cast<bool>(roll_ptr >> 55); +} + +/***********************************************************************//** +Determine if DB_ROLL_PTR is of the insert type. +@return true if insert */ +UNIV_INLINE +bool +trx_undo_roll_ptr_is_insert( +/*========================*/ + roll_ptr_t roll_ptr) /*!< in: roll pointer */ +{ + compile_time_assert(DATA_ROLL_PTR_LEN == 7); + ut_ad(roll_ptr < (1ULL << (ROLL_PTR_INSERT_FLAG_POS + 1))); + return static_cast<bool>(roll_ptr >> ROLL_PTR_INSERT_FLAG_POS); +} + +/***********************************************************************//** +Returns true if the record is of the insert type. +@return true if the record was freshly inserted (not updated). */ +UNIV_INLINE +bool +trx_undo_trx_id_is_insert( +/*======================*/ + const byte* trx_id) /*!< in: DB_TRX_ID, followed by DB_ROLL_PTR */ +{ + compile_time_assert(DATA_TRX_ID + 1 == DATA_ROLL_PTR); + return bool(trx_id[DATA_TRX_ID_LEN] >> 7); +} + +/** Gets an undo log page and x-latches it. +@param[in] page_id page id +@param[in,out] mtr mini-transaction +@return pointer to page x-latched */ +UNIV_INLINE +buf_block_t* +trx_undo_page_get(const page_id_t page_id, mtr_t* mtr) +{ + return buf_page_get(page_id, 0, RW_X_LATCH, mtr); +} + +/** Gets an undo log page and s-latches it. +@param[in] page_id page id +@param[in,out] mtr mini-transaction +@return pointer to page s-latched */ +UNIV_INLINE +buf_block_t* +trx_undo_page_get_s_latched(const page_id_t page_id, mtr_t* mtr) +{ + return buf_page_get(page_id, 0, RW_S_LATCH, mtr); +} + +/** Determine the end offset of undo log records of an undo log page. +@param[in] undo_page undo log page +@param[in] page_no undo log header page number +@param[in] offset undo log header offset +@return end offset */ +inline +uint16_t trx_undo_page_get_end(const buf_block_t *undo_page, uint32_t page_no, + uint16_t offset) +{ + if (page_no == undo_page->page.id().page_no()) + if (uint16_t end = mach_read_from_2(TRX_UNDO_NEXT_LOG + offset + + undo_page->page.frame)) + return end; + + return mach_read_from_2(TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_FREE + + undo_page->page.frame); +} + +/** Get the next record in an undo log. +@param[in] undo_page undo log page +@param[in] rec undo record offset in the page +@param[in] page_no undo log header page number +@param[in] offset undo log header offset on page +@return undo log record, the page latched, NULL if none */ +inline trx_undo_rec_t* +trx_undo_page_get_next_rec(const buf_block_t *undo_page, uint16_t rec, + uint32_t page_no, uint16_t offset) +{ + uint16_t end= trx_undo_page_get_end(undo_page, page_no, offset); + uint16_t next= mach_read_from_2(undo_page->page.frame + rec); + return next == end ? nullptr : undo_page->page.frame + next; +} |