1/*****************************************************************************
2
3Copyright (c) 1996, 2013, Oracle and/or its affiliates. All Rights Reserved.
4Copyright (c) 2017, 2018, MariaDB Corporation.
5
6This program is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free Software
8Foundation; version 2 of the License.
9
10This program is distributed in the hope that it will be useful, but WITHOUT
11ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
12FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
13
14You should have received a copy of the GNU General Public License along with
15this program; if not, write to the Free Software Foundation, Inc.,
1651 Franklin Street, Suite 500, Boston, MA 02110-1335 USA
17
18*****************************************************************************/
19
20/**************************************************//**
21@file include/trx0rseg.ic
22Rollback segment
23
24Created 3/26/1996 Heikki Tuuri
25*******************************************************/
26
27#include "srv0srv.h"
28#include "mtr0log.h"
29
30/** Gets a rollback segment header.
31@param[in] space space where placed
32@param[in] page_no page number of the header
33@param[in,out] mtr mini-transaction
34@return rollback segment header, page x-latched */
35UNIV_INLINE
36trx_rsegf_t*
37trx_rsegf_get(fil_space_t* space, ulint page_no, mtr_t* mtr)
38{
39 ut_ad(space == fil_system.sys_space || space == fil_system.temp_space
40 || srv_is_undo_tablespace(space->id)
41 || !srv_was_started);
42
43 buf_block_t* block = buf_page_get(page_id_t(space->id, page_no),
44 univ_page_size, RW_X_LATCH, mtr);
45
46 buf_block_dbg_add_level(block, SYNC_RSEG_HEADER);
47
48 return TRX_RSEG + block->frame;
49}
50
51/** Gets a newly created rollback segment header.
52@param[in] space space where placed
53@param[in] page_no page number of the header
54@param[in,out] mtr mini-transaction
55@return rollback segment header, page x-latched */
56UNIV_INLINE
57trx_rsegf_t*
58trx_rsegf_get_new(
59 ulint space,
60 ulint page_no,
61 mtr_t* mtr)
62{
63 buf_block_t* block;
64 trx_rsegf_t* header;
65
66 ut_ad(space <= srv_undo_tablespaces_active || space == SRV_TMP_SPACE_ID
67 || !srv_was_started);
68 ut_ad(space <= TRX_SYS_MAX_UNDO_SPACES || space == SRV_TMP_SPACE_ID);
69
70 block = buf_page_get(
71 page_id_t(space, page_no), univ_page_size, RW_X_LATCH, mtr);
72
73 buf_block_dbg_add_level(block, SYNC_RSEG_HEADER_NEW);
74
75 header = TRX_RSEG + buf_block_get_frame(block);
76
77 return(header);
78}
79
80/***************************************************************//**
81Sets the file page number of the nth undo log slot. */
82UNIV_INLINE
83void
84trx_rsegf_set_nth_undo(
85/*===================*/
86 trx_rsegf_t* rsegf, /*!< in: rollback segment header */
87 ulint n, /*!< in: index of slot */
88 ulint page_no,/*!< in: page number of the undo log segment */
89 mtr_t* mtr) /*!< in: mtr */
90{
91 ut_a(n < TRX_RSEG_N_SLOTS);
92
93 mlog_write_ulint(rsegf + TRX_RSEG_UNDO_SLOTS + n * TRX_RSEG_SLOT_SIZE,
94 page_no, MLOG_4BYTES, mtr);
95}
96
97/****************************************************************//**
98Looks for a free slot for an undo log segment.
99@return slot index or ULINT_UNDEFINED if not found */
100UNIV_INLINE
101ulint
102trx_rsegf_undo_find_free(const trx_rsegf_t* rsegf)
103{
104 ulint i;
105 ulint page_no;
106 ulint max_slots = TRX_RSEG_N_SLOTS;
107
108#ifdef UNIV_DEBUG
109 if (trx_rseg_n_slots_debug) {
110 max_slots = ut_min(static_cast<ulint>(trx_rseg_n_slots_debug),
111 static_cast<ulint>(TRX_RSEG_N_SLOTS));
112 }
113#endif
114
115 for (i = 0; i < max_slots; i++) {
116 page_no = trx_rsegf_get_nth_undo(rsegf, i);
117
118 if (page_no == FIL_NULL) {
119 return(i);
120 }
121 }
122
123 return(ULINT_UNDEFINED);
124}
125