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Diffstat (limited to 'storage/innobase/btr/btr0cur.cc')
| -rw-r--r-- | storage/innobase/btr/btr0cur.cc | 8279 |
1 files changed, 8279 insertions, 0 deletions
diff --git a/storage/innobase/btr/btr0cur.cc b/storage/innobase/btr/btr0cur.cc new file mode 100644 index 00000000..5bb2a0e2 --- /dev/null +++ b/storage/innobase/btr/btr0cur.cc @@ -0,0 +1,8279 @@ +/***************************************************************************** + +Copyright (c) 1994, 2019, Oracle and/or its affiliates. All Rights Reserved. +Copyright (c) 2008, Google Inc. +Copyright (c) 2012, Facebook Inc. +Copyright (c) 2015, 2021, MariaDB Corporation. + +Portions of this file contain modifications contributed and copyrighted by +Google, Inc. Those modifications are gratefully acknowledged and are described +briefly in the InnoDB documentation. The contributions by Google are +incorporated with their permission, and subject to the conditions contained in +the file COPYING.Google. + +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 btr/btr0cur.cc +The index tree cursor + +All changes that row operations make to a B-tree or the records +there must go through this module! Undo log records are written here +of every modify or insert of a clustered index record. + + NOTE!!! +To make sure we do not run out of disk space during a pessimistic +insert or update, we have to reserve 2 x the height of the index tree +many pages in the tablespace before we start the operation, because +if leaf splitting has been started, it is difficult to undo, except +by crashing the database and doing a roll-forward. + +Created 10/16/1994 Heikki Tuuri +*******************************************************/ + +#include "btr0cur.h" +#include "row0upd.h" +#include "mtr0log.h" +#include "page0page.h" +#include "page0zip.h" +#include "rem0rec.h" +#include "rem0cmp.h" +#include "buf0lru.h" +#include "btr0btr.h" +#include "btr0sea.h" +#include "row0log.h" +#include "row0purge.h" +#include "row0upd.h" +#include "trx0rec.h" +#include "trx0roll.h" +#include "que0que.h" +#include "row0row.h" +#include "srv0srv.h" +#include "ibuf0ibuf.h" +#include "lock0lock.h" +#include "zlib.h" +#include "srv0start.h" +#include "mysql_com.h" +#include "dict0stats.h" +#ifdef WITH_WSREP +#include "mysql/service_wsrep.h" +#endif /* WITH_WSREP */ + +/** Buffered B-tree operation types, introduced as part of delete buffering. */ +enum btr_op_t { + BTR_NO_OP = 0, /*!< Not buffered */ + BTR_INSERT_OP, /*!< Insert, do not ignore UNIQUE */ + BTR_INSERT_IGNORE_UNIQUE_OP, /*!< Insert, ignoring UNIQUE */ + BTR_DELETE_OP, /*!< Purge a delete-marked record */ + BTR_DELMARK_OP /*!< Mark a record for deletion */ +}; + +/** Modification types for the B-tree operation. + Note that the order must be DELETE, BOTH, INSERT !! + */ +enum btr_intention_t { + BTR_INTENTION_DELETE, + BTR_INTENTION_BOTH, + BTR_INTENTION_INSERT +}; + +/** For the index->lock scalability improvement, only possibility of clear +performance regression observed was caused by grown huge history list length. +That is because the exclusive use of index->lock also worked as reserving +free blocks and read IO bandwidth with priority. To avoid huge glowing history +list as same level with previous implementation, prioritizes pessimistic tree +operations by purge as the previous, when it seems to be growing huge. + + Experimentally, the history list length starts to affect to performance +throughput clearly from about 100000. */ +#define BTR_CUR_FINE_HISTORY_LENGTH 100000 + +/** Number of searches down the B-tree in btr_cur_search_to_nth_level(). */ +Atomic_counter<ulint> btr_cur_n_non_sea; +/** Old value of btr_cur_n_non_sea. Copied by +srv_refresh_innodb_monitor_stats(). Referenced by +srv_printf_innodb_monitor(). */ +ulint btr_cur_n_non_sea_old; +#ifdef BTR_CUR_HASH_ADAPT +/** Number of successful adaptive hash index lookups in +btr_cur_search_to_nth_level(). */ +ulint btr_cur_n_sea; +/** Old value of btr_cur_n_sea. Copied by +srv_refresh_innodb_monitor_stats(). Referenced by +srv_printf_innodb_monitor(). */ +ulint btr_cur_n_sea_old; +#endif /* BTR_CUR_HASH_ADAPT */ + +#ifdef UNIV_DEBUG +/* Flag to limit optimistic insert records */ +uint btr_cur_limit_optimistic_insert_debug; +#endif /* UNIV_DEBUG */ + +/** In the optimistic insert, if the insert does not fit, but this much space +can be released by page reorganize, then it is reorganized */ +#define BTR_CUR_PAGE_REORGANIZE_LIMIT (srv_page_size / 32) + +/** The structure of a BLOB part header */ +/* @{ */ +/*--------------------------------------*/ +#define BTR_BLOB_HDR_PART_LEN 0 /*!< BLOB part len on this + page */ +#define BTR_BLOB_HDR_NEXT_PAGE_NO 4 /*!< next BLOB part page no, + FIL_NULL if none */ +/*--------------------------------------*/ +#define BTR_BLOB_HDR_SIZE 8 /*!< Size of a BLOB + part header, in bytes */ + +/** Estimated table level stats from sampled value. +@param value sampled stats +@param index index being sampled +@param sample number of sampled rows +@param ext_size external stored data size +@param not_empty table not empty +@return estimated table wide stats from sampled value */ +#define BTR_TABLE_STATS_FROM_SAMPLE(value, index, sample, ext_size, not_empty) \ + (((value) * static_cast<ib_uint64_t>(index->stat_n_leaf_pages) \ + + (sample) - 1 + (ext_size) + (not_empty)) / ((sample) + (ext_size))) + +/* @} */ + +/*******************************************************************//** +Marks all extern fields in a record as owned by the record. This function +should be called if the delete mark of a record is removed: a not delete +marked record always owns all its extern fields. */ +static +void +btr_cur_unmark_extern_fields( +/*=========================*/ + buf_block_t* block, /*!< in/out: index page */ + rec_t* rec, /*!< in/out: record in a clustered index */ + dict_index_t* index, /*!< in: index of the page */ + const rec_offs* offsets,/*!< in: array returned by rec_get_offsets() */ + mtr_t* mtr); /*!< in: mtr, or NULL if not logged */ +/*******************************************************************//** +Adds path information to the cursor for the current page, for which +the binary search has been performed. */ +static +void +btr_cur_add_path_info( +/*==================*/ + btr_cur_t* cursor, /*!< in: cursor positioned on a page */ + ulint height, /*!< in: height of the page in tree; + 0 means leaf node */ + ulint root_height); /*!< in: root node height in tree */ +/***********************************************************//** +Frees the externally stored fields for a record, if the field is mentioned +in the update vector. */ +static +void +btr_rec_free_updated_extern_fields( +/*===============================*/ + dict_index_t* index, /*!< in: index of rec; the index tree MUST be + X-latched */ + rec_t* rec, /*!< in: record */ + buf_block_t* block, /*!< in: index page of rec */ + const rec_offs* offsets,/*!< in: rec_get_offsets(rec, index) */ + const upd_t* update, /*!< in: update vector */ + bool rollback,/*!< in: performing rollback? */ + mtr_t* mtr); /*!< in: mini-transaction handle which contains + an X-latch to record page and to the tree */ +/***********************************************************//** +Frees the externally stored fields for a record. */ +static +void +btr_rec_free_externally_stored_fields( +/*==================================*/ + dict_index_t* index, /*!< in: index of the data, the index + tree MUST be X-latched */ + rec_t* rec, /*!< in: record */ + const rec_offs* offsets,/*!< in: rec_get_offsets(rec, index) */ + buf_block_t* block, /*!< in: index page of rec */ + bool rollback,/*!< in: performing rollback? */ + mtr_t* mtr); /*!< in: mini-transaction handle which contains + an X-latch to record page and to the index + tree */ + +/*==================== B-TREE SEARCH =========================*/ + +/** Latches the leaf page or pages requested. +@param[in] block leaf page where the search converged +@param[in] latch_mode BTR_SEARCH_LEAF, ... +@param[in] cursor cursor +@param[in] mtr mini-transaction +@return blocks and savepoints which actually latched. */ +btr_latch_leaves_t +btr_cur_latch_leaves( + buf_block_t* block, + ulint latch_mode, + btr_cur_t* cursor, + mtr_t* mtr) +{ + rw_lock_type_t mode; + uint32_t left_page_no; + uint32_t right_page_no; + buf_block_t* get_block; + bool spatial; + btr_latch_leaves_t latch_leaves = {{NULL, NULL, NULL}, {0, 0, 0}}; + + compile_time_assert(int(MTR_MEMO_PAGE_S_FIX) == int(RW_S_LATCH)); + compile_time_assert(int(MTR_MEMO_PAGE_X_FIX) == int(RW_X_LATCH)); + compile_time_assert(int(MTR_MEMO_PAGE_SX_FIX) == int(RW_SX_LATCH)); + ut_ad(block->page.id().space() == cursor->index->table->space->id); + + spatial = dict_index_is_spatial(cursor->index) && cursor->rtr_info; + ut_ad(block->page.in_file()); + + switch (latch_mode) { + case BTR_SEARCH_LEAF: + case BTR_MODIFY_LEAF: + case BTR_SEARCH_TREE: + if (spatial) { + cursor->rtr_info->tree_savepoints[RTR_MAX_LEVELS] + = mtr_set_savepoint(mtr); + } + + mode = latch_mode == BTR_MODIFY_LEAF ? RW_X_LATCH : RW_S_LATCH; + latch_leaves.savepoints[1] = mtr_set_savepoint(mtr); + get_block = btr_block_get(*cursor->index, + block->page.id().page_no(), mode, + true, mtr); + latch_leaves.blocks[1] = get_block; +#ifdef UNIV_BTR_DEBUG + ut_a(page_is_comp(get_block->frame) + == page_is_comp(block->frame)); +#endif /* UNIV_BTR_DEBUG */ + if (spatial) { + cursor->rtr_info->tree_blocks[RTR_MAX_LEVELS] + = get_block; + } + + return(latch_leaves); + case BTR_MODIFY_TREE: + /* It is exclusive for other operations which calls + btr_page_set_prev() */ + ut_ad(mtr->memo_contains_flagged(&cursor->index->lock, + MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + /* x-latch also siblings from left to right */ + left_page_no = btr_page_get_prev(block->frame); + + if (left_page_no != FIL_NULL) { + + if (spatial) { + cursor->rtr_info->tree_savepoints[ + RTR_MAX_LEVELS] = mtr_set_savepoint(mtr); + } + + latch_leaves.savepoints[0] = mtr_set_savepoint(mtr); + get_block = btr_block_get( + *cursor->index, left_page_no, RW_X_LATCH, + true, mtr); + latch_leaves.blocks[0] = get_block; + + if (spatial) { + cursor->rtr_info->tree_blocks[RTR_MAX_LEVELS] + = get_block; + } + } + + if (spatial) { + cursor->rtr_info->tree_savepoints[RTR_MAX_LEVELS + 1] + = mtr_set_savepoint(mtr); + } + + latch_leaves.savepoints[1] = mtr_set_savepoint(mtr); + get_block = btr_block_get( + *cursor->index, block->page.id().page_no(), + RW_X_LATCH, true, mtr); + latch_leaves.blocks[1] = get_block; + +#ifdef UNIV_BTR_DEBUG + /* Sanity check only after both the blocks are latched. */ + if (latch_leaves.blocks[0] != NULL) { + ut_a(page_is_comp(latch_leaves.blocks[0]->frame) + == page_is_comp(block->frame)); + ut_a(btr_page_get_next(latch_leaves.blocks[0]->frame) + == block->page.id().page_no()); + } + ut_a(page_is_comp(get_block->frame) + == page_is_comp(block->frame)); +#endif /* UNIV_BTR_DEBUG */ + + if (spatial) { + cursor->rtr_info->tree_blocks[RTR_MAX_LEVELS + 1] + = get_block; + } + + right_page_no = btr_page_get_next(block->frame); + + if (right_page_no != FIL_NULL) { + if (spatial) { + cursor->rtr_info->tree_savepoints[ + RTR_MAX_LEVELS + 2] = mtr_set_savepoint( + mtr); + } + latch_leaves.savepoints[2] = mtr_set_savepoint(mtr); + get_block = btr_block_get(*cursor->index, + right_page_no, RW_X_LATCH, + true, mtr); + latch_leaves.blocks[2] = get_block; +#ifdef UNIV_BTR_DEBUG + ut_a(page_is_comp(get_block->frame) + == page_is_comp(block->frame)); + ut_a(btr_page_get_prev(get_block->frame) + == block->page.id().page_no()); +#endif /* UNIV_BTR_DEBUG */ + if (spatial) { + cursor->rtr_info->tree_blocks[ + RTR_MAX_LEVELS + 2] = get_block; + } + } + + return(latch_leaves); + + case BTR_SEARCH_PREV: + case BTR_MODIFY_PREV: + mode = latch_mode == BTR_SEARCH_PREV ? RW_S_LATCH : RW_X_LATCH; + /* latch also left sibling */ + rw_lock_s_lock(&block->lock); + left_page_no = btr_page_get_prev(block->frame); + rw_lock_s_unlock(&block->lock); + + if (left_page_no != FIL_NULL) { + latch_leaves.savepoints[0] = mtr_set_savepoint(mtr); + get_block = btr_block_get( + *cursor->index, left_page_no, mode, + true, mtr); + latch_leaves.blocks[0] = get_block; + cursor->left_block = get_block; +#ifdef UNIV_BTR_DEBUG + ut_a(page_is_comp(get_block->frame) + == page_is_comp(block->frame)); + ut_a(btr_page_get_next(get_block->frame) + == block->page.id().page_no()); +#endif /* UNIV_BTR_DEBUG */ + } + + latch_leaves.savepoints[1] = mtr_set_savepoint(mtr); + get_block = btr_block_get(*cursor->index, + block->page.id().page_no(), mode, + true, mtr); + latch_leaves.blocks[1] = get_block; +#ifdef UNIV_BTR_DEBUG + ut_a(page_is_comp(get_block->frame) + == page_is_comp(block->frame)); +#endif /* UNIV_BTR_DEBUG */ + return(latch_leaves); + case BTR_CONT_MODIFY_TREE: + ut_ad(dict_index_is_spatial(cursor->index)); + return(latch_leaves); + } + + ut_error; + return(latch_leaves); +} + +/** Load the instant ALTER TABLE metadata from the clustered index +when loading a table definition. +@param[in,out] index clustered index definition +@param[in,out] mtr mini-transaction +@return error code +@retval DB_SUCCESS if no error occurred +@retval DB_CORRUPTION if any corruption was noticed */ +static dberr_t btr_cur_instant_init_low(dict_index_t* index, mtr_t* mtr) +{ + ut_ad(index->is_primary()); + ut_ad(index->n_core_null_bytes == dict_index_t::NO_CORE_NULL_BYTES); + ut_ad(index->table->supports_instant()); + ut_ad(index->table->is_readable()); + + const fil_space_t* space = index->table->space; + if (!space) { +unreadable: + ib::error() << "Table " << index->table->name + << " has an unreadable root page"; + index->table->corrupted = true; + return DB_CORRUPTION; + } + + page_t* root = btr_root_get(index, mtr); + + if (!root || btr_cur_instant_root_init(index, root)) { + goto unreadable; + } + + ut_ad(index->n_core_null_bytes != dict_index_t::NO_CORE_NULL_BYTES); + + if (fil_page_get_type(root) == FIL_PAGE_INDEX) { + ut_ad(!index->is_instant()); + return DB_SUCCESS; + } + + btr_cur_t cur; + /* Relax the assertion in rec_init_offsets(). */ + ut_ad(!index->in_instant_init); + ut_d(index->in_instant_init = true); + dberr_t err = btr_cur_open_at_index_side(true, index, BTR_SEARCH_LEAF, + &cur, 0, mtr); + ut_d(index->in_instant_init = false); + if (err != DB_SUCCESS) { + index->table->corrupted = true; + return err; + } + + ut_ad(page_cur_is_before_first(&cur.page_cur)); + ut_ad(page_is_leaf(cur.page_cur.block->frame)); + + page_cur_move_to_next(&cur.page_cur); + + const rec_t* rec = cur.page_cur.rec; + const ulint comp = dict_table_is_comp(index->table); + const ulint info_bits = rec_get_info_bits(rec, comp); + + if (page_rec_is_supremum(rec) + || !(info_bits & REC_INFO_MIN_REC_FLAG)) { + if (!index->is_instant()) { + /* The FIL_PAGE_TYPE_INSTANT and PAGE_INSTANT may be + assigned even if instant ADD COLUMN was not + committed. Changes to these page header fields are not + undo-logged, but changes to the hidden metadata record + are. If the server is killed and restarted, the page + header fields could remain set even though no metadata + record is present. */ + return DB_SUCCESS; + } + + ib::error() << "Table " << index->table->name + << " is missing instant ALTER metadata"; + index->table->corrupted = true; + return DB_CORRUPTION; + } + + if ((info_bits & ~REC_INFO_DELETED_FLAG) != REC_INFO_MIN_REC_FLAG + || (comp && rec_get_status(rec) != REC_STATUS_INSTANT)) { +incompatible: + ib::error() << "Table " << index->table->name + << " contains unrecognizable instant ALTER metadata"; + index->table->corrupted = true; + return DB_CORRUPTION; + } + + /* Read the metadata. We can get here on server restart + or when the table was evicted from the data dictionary cache + and is now being accessed again. + + Here, READ COMMITTED and REPEATABLE READ should be equivalent. + Committing the ADD COLUMN operation would acquire + MDL_EXCLUSIVE and LOCK_X|LOCK_TABLE, which would prevent any + concurrent operations on the table, including table eviction + from the cache. */ + + if (info_bits & REC_INFO_DELETED_FLAG) { + /* This metadata record includes a BLOB that identifies + any dropped or reordered columns. */ + ulint trx_id_offset = index->trx_id_offset; + /* If !index->trx_id_offset, the PRIMARY KEY contains + variable-length columns. For the metadata record, + variable-length columns should be written with zero + length. However, before MDEV-21088 was fixed, for + variable-length encoded PRIMARY KEY column of type + CHAR, we wrote more than zero bytes. That is why we + must determine the actual length of each PRIMARY KEY + column. The DB_TRX_ID will start right after any + PRIMARY KEY columns. */ + ut_ad(index->n_uniq); + + /* We cannot invoke rec_get_offsets() before + index->table->deserialise_columns(). Therefore, + we must duplicate some logic here. */ + if (trx_id_offset) { + } else if (index->table->not_redundant()) { + /* The PRIMARY KEY contains variable-length columns. + For the metadata record, variable-length columns are + always written with zero length. The DB_TRX_ID will + start right after any fixed-length columns. */ + + /* OK, before MDEV-21088 was fixed, for + variable-length encoded PRIMARY KEY column of + type CHAR, we wrote more than zero bytes. In + order to allow affected tables to be accessed, + it would be nice to determine the actual + length of each PRIMARY KEY column. However, to + be able to do that, we should determine the + size of the null-bit bitmap in the metadata + record. And we cannot know that before reading + the metadata BLOB, whose starting point we are + trying to find here. (Although the PRIMARY KEY + columns cannot be NULL, we would have to know + where the lengths of variable-length PRIMARY KEY + columns start.) + + So, unfortunately we cannot help users who + were affected by MDEV-21088 on a ROW_FORMAT=COMPACT + or ROW_FORMAT=DYNAMIC table. */ + + for (uint i = index->n_uniq; i--; ) { + trx_id_offset += index->fields[i].fixed_len; + } + } else if (rec_get_1byte_offs_flag(rec)) { + trx_id_offset = rec_1_get_field_end_info( + rec, index->n_uniq - 1); + ut_ad(!(trx_id_offset & REC_1BYTE_SQL_NULL_MASK)); + trx_id_offset &= ~REC_1BYTE_SQL_NULL_MASK; + } else { + trx_id_offset = rec_2_get_field_end_info( + rec, index->n_uniq - 1); + ut_ad(!(trx_id_offset & REC_2BYTE_SQL_NULL_MASK)); + trx_id_offset &= ~REC_2BYTE_SQL_NULL_MASK; + } + + const byte* ptr = rec + trx_id_offset + + (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN); + + if (mach_read_from_4(ptr + BTR_EXTERN_LEN)) { + goto incompatible; + } + + uint len = mach_read_from_4(ptr + BTR_EXTERN_LEN + 4); + if (!len + || mach_read_from_4(ptr + BTR_EXTERN_OFFSET) + != FIL_PAGE_DATA + || mach_read_from_4(ptr + BTR_EXTERN_SPACE_ID) + != space->id) { + goto incompatible; + } + + buf_block_t* block = buf_page_get( + page_id_t(space->id, + mach_read_from_4(ptr + BTR_EXTERN_PAGE_NO)), + 0, RW_S_LATCH, mtr); + buf_block_dbg_add_level(block, SYNC_EXTERN_STORAGE); + if (fil_page_get_type(block->frame) != FIL_PAGE_TYPE_BLOB + || mach_read_from_4(&block->frame[FIL_PAGE_DATA + + BTR_BLOB_HDR_NEXT_PAGE_NO]) + != FIL_NULL + || mach_read_from_4(&block->frame[FIL_PAGE_DATA + + BTR_BLOB_HDR_PART_LEN]) + != len) { + goto incompatible; + } + + /* The unused part of the BLOB page should be zero-filled. */ + for (const byte* b = block->frame + + (FIL_PAGE_DATA + BTR_BLOB_HDR_SIZE) + len, + * const end = block->frame + srv_page_size + - BTR_EXTERN_LEN; + b < end; ) { + if (*b++) { + goto incompatible; + } + } + + if (index->table->deserialise_columns( + &block->frame[FIL_PAGE_DATA + BTR_BLOB_HDR_SIZE], + len)) { + goto incompatible; + } + + /* Proceed to initialize the default values of + any instantly added columns. */ + } + + mem_heap_t* heap = NULL; + rec_offs* offsets = rec_get_offsets(rec, index, NULL, + index->n_core_fields, + ULINT_UNDEFINED, &heap); + if (rec_offs_any_default(offsets)) { +inconsistent: + mem_heap_free(heap); + goto incompatible; + } + + /* In fact, because we only ever append fields to the metadata + record, it is also OK to perform READ UNCOMMITTED and + then ignore any extra fields, provided that + trx_sys.is_registered(DB_TRX_ID). */ + if (rec_offs_n_fields(offsets) + > ulint(index->n_fields) + !!index->table->instant + && !trx_sys.is_registered(current_trx(), + row_get_rec_trx_id(rec, index, + offsets))) { + goto inconsistent; + } + + for (unsigned i = index->n_core_fields; i < index->n_fields; i++) { + dict_col_t* col = index->fields[i].col; + const unsigned o = i + !!index->table->instant; + ulint len; + const byte* data = rec_get_nth_field(rec, offsets, o, &len); + ut_ad(!col->is_added()); + ut_ad(!col->def_val.data); + col->def_val.len = len; + switch (len) { + case UNIV_SQL_NULL: + continue; + case 0: + col->def_val.data = field_ref_zero; + continue; + } + ut_ad(len != UNIV_SQL_DEFAULT); + if (!rec_offs_nth_extern(offsets, o)) { + col->def_val.data = mem_heap_dup( + index->table->heap, data, len); + } else if (len < BTR_EXTERN_FIELD_REF_SIZE + || !memcmp(data + len - BTR_EXTERN_FIELD_REF_SIZE, + field_ref_zero, + BTR_EXTERN_FIELD_REF_SIZE)) { + col->def_val.len = UNIV_SQL_DEFAULT; + goto inconsistent; + } else { + col->def_val.data = btr_copy_externally_stored_field( + &col->def_val.len, data, + cur.page_cur.block->zip_size(), + len, index->table->heap); + } + } + + mem_heap_free(heap); + return DB_SUCCESS; +} + +/** Load the instant ALTER TABLE metadata from the clustered index +when loading a table definition. +@param[in,out] table table definition from the data dictionary +@return error code +@retval DB_SUCCESS if no error occurred */ +dberr_t +btr_cur_instant_init(dict_table_t* table) +{ + mtr_t mtr; + dict_index_t* index = dict_table_get_first_index(table); + mtr.start(); + dberr_t err = index + ? btr_cur_instant_init_low(index, &mtr) + : DB_CORRUPTION; + mtr.commit(); + return(err); +} + +/** Initialize the n_core_null_bytes on first access to a clustered +index root page. +@param[in] index clustered index that is on its first access +@param[in] page clustered index root page +@return whether the page is corrupted */ +bool btr_cur_instant_root_init(dict_index_t* index, const page_t* page) +{ + ut_ad(!index->is_dummy); + ut_ad(fil_page_index_page_check(page)); + ut_ad(!page_has_siblings(page)); + ut_ad(page_get_space_id(page) == index->table->space_id); + ut_ad(page_get_page_no(page) == index->page); + ut_ad(!page_is_comp(page) == !dict_table_is_comp(index->table)); + ut_ad(index->is_primary()); + ut_ad(!index->is_instant()); + ut_ad(index->table->supports_instant()); + /* This is normally executed as part of btr_cur_instant_init() + when dict_load_table_one() is loading a table definition. + Other threads should not access or modify the n_core_null_bytes, + n_core_fields before dict_load_table_one() returns. + + This can also be executed during IMPORT TABLESPACE, where the + table definition is exclusively locked. */ + + switch (fil_page_get_type(page)) { + default: + ut_ad("wrong page type" == 0); + return true; + case FIL_PAGE_INDEX: + /* The field PAGE_INSTANT is guaranteed 0 on clustered + index root pages of ROW_FORMAT=COMPACT or + ROW_FORMAT=DYNAMIC when instant ADD COLUMN is not used. */ + ut_ad(!page_is_comp(page) || !page_get_instant(page)); + index->n_core_null_bytes = static_cast<uint8_t>( + UT_BITS_IN_BYTES(unsigned(index->n_nullable))); + return false; + case FIL_PAGE_TYPE_INSTANT: + break; + } + + const uint16_t n = page_get_instant(page); + + if (n < index->n_uniq + DATA_ROLL_PTR) { + /* The PRIMARY KEY (or hidden DB_ROW_ID) and + DB_TRX_ID,DB_ROLL_PTR columns must always be present + as 'core' fields. */ + return true; + } + + if (n > REC_MAX_N_FIELDS) { + return true; + } + + index->n_core_fields = n & dict_index_t::MAX_N_FIELDS; + + const rec_t* infimum = page_get_infimum_rec(page); + const rec_t* supremum = page_get_supremum_rec(page); + + if (!memcmp(infimum, "infimum", 8) + && !memcmp(supremum, "supremum", 8)) { + if (n > index->n_fields) { + /* All fields, including those for instantly + added columns, must be present in the + data dictionary. */ + return true; + } + + ut_ad(!index->is_dummy); + ut_d(index->is_dummy = true); + index->n_core_null_bytes = static_cast<uint8_t>( + UT_BITS_IN_BYTES(index->get_n_nullable(n))); + ut_d(index->is_dummy = false); + return false; + } + + if (memcmp(infimum, field_ref_zero, 8) + || memcmp(supremum, field_ref_zero, 7)) { + /* The infimum and supremum records must either contain + the original strings, or they must be filled with zero + bytes, except for the bytes that we have repurposed. */ + return true; + } + + index->n_core_null_bytes = supremum[7]; + return index->n_core_null_bytes > 128; +} + +/** Optimistically latches the leaf page or pages requested. +@param[in] block guessed buffer block +@param[in] modify_clock modify clock value +@param[in,out] latch_mode BTR_SEARCH_LEAF, ... +@param[in,out] cursor cursor +@param[in] file file name +@param[in] line line where called +@param[in] mtr mini-transaction +@return true if success */ +bool +btr_cur_optimistic_latch_leaves( + buf_block_t* block, + ib_uint64_t modify_clock, + ulint* latch_mode, + btr_cur_t* cursor, + const char* file, + unsigned line, + mtr_t* mtr) +{ + ut_ad(block->page.buf_fix_count()); + ut_ad(block->page.state() == BUF_BLOCK_FILE_PAGE); + + switch (*latch_mode) { + default: + ut_error; + return(false); + case BTR_SEARCH_LEAF: + case BTR_MODIFY_LEAF: + return(buf_page_optimistic_get(*latch_mode, block, + modify_clock, file, line, mtr)); + case BTR_SEARCH_PREV: + case BTR_MODIFY_PREV: + rw_lock_s_lock(&block->lock); + if (block->modify_clock != modify_clock) { + rw_lock_s_unlock(&block->lock); + return false; + } + const uint32_t curr_page_no = block->page.id().page_no(); + const uint32_t left_page_no = btr_page_get_prev(block->frame); + rw_lock_s_unlock(&block->lock); + + const rw_lock_type_t mode = *latch_mode == BTR_SEARCH_PREV + ? RW_S_LATCH : RW_X_LATCH; + + if (left_page_no != FIL_NULL) { + dberr_t err = DB_SUCCESS; + cursor->left_block = buf_page_get_gen( + page_id_t(cursor->index->table->space_id, + left_page_no), + cursor->index->table->space->zip_size(), + mode, nullptr, BUF_GET_POSSIBLY_FREED, + __FILE__, __LINE__, mtr, &err); + + if (!cursor->left_block) { + cursor->index->table->file_unreadable = true; + } + + if (cursor->left_block->page.status + == buf_page_t::FREED + || btr_page_get_next(cursor->left_block->frame) + != curr_page_no) { + /* release the left block */ + btr_leaf_page_release( + cursor->left_block, mode, mtr); + return false; + } + } else { + cursor->left_block = NULL; + } + + if (buf_page_optimistic_get(mode, block, modify_clock, + file, line, mtr)) { + if (btr_page_get_prev(block->frame) == left_page_no) { + /* block was already buffer-fixed while + entering the function and + buf_page_optimistic_get() buffer-fixes + it again. */ + ut_ad(2 <= block->page.buf_fix_count()); + *latch_mode = mode; + return(true); + } else { + /* release the block and decrement of + buf_fix_count which was incremented + in buf_page_optimistic_get() */ + btr_leaf_page_release(block, mode, mtr); + } + } + + ut_ad(block->page.buf_fix_count()); + /* release the left block */ + if (cursor->left_block != NULL) { + btr_leaf_page_release(cursor->left_block, + mode, mtr); + } + } + + return false; +} + +/** +Gets intention in btr_intention_t from latch_mode, and cleares the intention +at the latch_mode. +@param latch_mode in/out: pointer to latch_mode +@return intention for latching tree */ +static +btr_intention_t +btr_cur_get_and_clear_intention( + ulint *latch_mode) +{ + btr_intention_t intention; + + switch (*latch_mode & (BTR_LATCH_FOR_INSERT | BTR_LATCH_FOR_DELETE)) { + case BTR_LATCH_FOR_INSERT: + intention = BTR_INTENTION_INSERT; + break; + case BTR_LATCH_FOR_DELETE: + intention = BTR_INTENTION_DELETE; + break; + default: + /* both or unknown */ + intention = BTR_INTENTION_BOTH; + } + *latch_mode &= ulint(~(BTR_LATCH_FOR_INSERT | BTR_LATCH_FOR_DELETE)); + + return(intention); +} + +/** +Gets the desired latch type for the root leaf (root page is root leaf) +at the latch mode. +@param latch_mode in: BTR_SEARCH_LEAF, ... +@return latch type */ +static +rw_lock_type_t +btr_cur_latch_for_root_leaf( + ulint latch_mode) +{ + switch (latch_mode) { + case BTR_SEARCH_LEAF: + case BTR_SEARCH_TREE: + case BTR_SEARCH_PREV: + return(RW_S_LATCH); + case BTR_MODIFY_LEAF: + case BTR_MODIFY_TREE: + case BTR_MODIFY_PREV: + return(RW_X_LATCH); + case BTR_CONT_MODIFY_TREE: + case BTR_CONT_SEARCH_TREE: + /* A root page should be latched already, + and don't need to be latched here. + fall through (RW_NO_LATCH) */ + case BTR_NO_LATCHES: + return(RW_NO_LATCH); + } + + ut_error; + return(RW_NO_LATCH); /* avoid compiler warnings */ +} + +/** Detects whether the modifying record might need a modifying tree structure. +@param[in] index index +@param[in] page page +@param[in] lock_intention lock intention for the tree operation +@param[in] rec record (current node_ptr) +@param[in] rec_size size of the record or max size of node_ptr +@param[in] zip_size ROW_FORMAT=COMPRESSED page size, or 0 +@param[in] mtr mtr +@return true if tree modification is needed */ +static +bool +btr_cur_will_modify_tree( + dict_index_t* index, + const page_t* page, + btr_intention_t lock_intention, + const rec_t* rec, + ulint rec_size, + ulint zip_size, + mtr_t* mtr) +{ + ut_ad(!page_is_leaf(page)); + ut_ad(mtr->memo_contains_flagged(&index->lock, MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + + /* Pessimistic delete of the first record causes delete & insert + of node_ptr at upper level. And a subsequent page shrink is + possible. It causes delete of node_ptr at the upper level. + So we should pay attention also to 2nd record not only + first record and last record. Because if the "delete & insert" are + done for the different page, the 2nd record become + first record and following compress might delete the record and causes + the uppper level node_ptr modification. */ + + const ulint n_recs = page_get_n_recs(page); + + if (lock_intention <= BTR_INTENTION_BOTH) { + compile_time_assert(BTR_INTENTION_DELETE < BTR_INTENTION_BOTH); + compile_time_assert(BTR_INTENTION_BOTH < BTR_INTENTION_INSERT); + + if (!page_has_siblings(page)) { + return true; + } + + ulint margin = rec_size; + + if (lock_intention == BTR_INTENTION_BOTH) { + ulint level = btr_page_get_level(page); + + /* This value is the worst expectation for the node_ptr + records to be deleted from this page. It is used to + expect whether the cursor position can be the left_most + record in this page or not. */ + ulint max_nodes_deleted = 0; + + /* By modifying tree operations from the under of this + level, logically (2 ^ (level - 1)) opportunities to + deleting records in maximum even unreally rare case. */ + if (level > 7) { + /* TODO: adjust this practical limit. */ + max_nodes_deleted = 64; + } else if (level > 0) { + max_nodes_deleted = (ulint)1 << (level - 1); + } + /* check delete will cause. (BTR_INTENTION_BOTH + or BTR_INTENTION_DELETE) */ + if (n_recs <= max_nodes_deleted * 2 + || page_rec_is_first(rec, page)) { + /* The cursor record can be the left most record + in this page. */ + return true; + } + + if (page_has_prev(page) + && page_rec_distance_is_at_most( + page_get_infimum_rec(page), rec, + max_nodes_deleted)) { + return true; + } + + if (page_has_next(page) + && page_rec_distance_is_at_most( + rec, page_get_supremum_rec(page), + max_nodes_deleted)) { + return true; + } + + /* Delete at leftmost record in a page causes delete + & insert at its parent page. After that, the delete + might cause btr_compress() and delete record at its + parent page. Thus we should consider max deletes. */ + margin *= max_nodes_deleted; + } + + /* Safe because we already have SX latch of the index tree */ + if (page_get_data_size(page) + < margin + BTR_CUR_PAGE_COMPRESS_LIMIT(index)) { + return(true); + } + } + + if (lock_intention >= BTR_INTENTION_BOTH) { + /* check insert will cause. BTR_INTENTION_BOTH + or BTR_INTENTION_INSERT*/ + + /* Once we invoke the btr_cur_limit_optimistic_insert_debug, + we should check it here in advance, since the max allowable + records in a page is limited. */ + LIMIT_OPTIMISTIC_INSERT_DEBUG(n_recs, return true); + + /* needs 2 records' space for the case the single split and + insert cannot fit. + page_get_max_insert_size_after_reorganize() includes space + for page directory already */ + ulint max_size + = page_get_max_insert_size_after_reorganize(page, 2); + + if (max_size < BTR_CUR_PAGE_REORGANIZE_LIMIT + rec_size + || max_size < rec_size * 2) { + return(true); + } + + /* TODO: optimize this condition for ROW_FORMAT=COMPRESSED. + This is based on the worst case, and we could invoke + page_zip_available() on the block->page.zip. */ + /* needs 2 records' space also for worst compress rate. */ + if (zip_size + && page_zip_empty_size(index->n_fields, zip_size) + <= rec_size * 2 + page_get_data_size(page) + + page_dir_calc_reserved_space(n_recs + 2)) { + return(true); + } + } + + return(false); +} + +/** Detects whether the modifying record might need a opposite modification +to the intention. +@param[in] page page +@param[in] lock_intention lock intention for the tree operation +@param[in] rec record (current node_ptr) +@return true if tree modification is needed */ +static +bool +btr_cur_need_opposite_intention( + const page_t* page, + btr_intention_t lock_intention, + const rec_t* rec) +{ + switch (lock_intention) { + case BTR_INTENTION_DELETE: + return (page_has_prev(page) && page_rec_is_first(rec, page)) || + (page_has_next(page) && page_rec_is_last(rec, page)); + case BTR_INTENTION_INSERT: + return page_has_next(page) && page_rec_is_last(rec, page); + case BTR_INTENTION_BOTH: + return(false); + } + + ut_error; + return(false); +} + +/** +@param[in] index b-tree +@return maximum size of a node pointer record in bytes */ +static ulint btr_node_ptr_max_size(const dict_index_t* index) +{ + if (dict_index_is_ibuf(index)) { + /* cannot estimate accurately */ + /* This is universal index for change buffer. + The max size of the entry is about max key length * 2. + (index key + primary key to be inserted to the index) + (The max key length is UNIV_PAGE_SIZE / 16 * 3 at + ha_innobase::max_supported_key_length(), + considering MAX_KEY_LENGTH = 3072 at MySQL imposes + the 3500 historical InnoDB value for 16K page size case.) + For the universal index, node_ptr contains most of the entry. + And 512 is enough to contain ibuf columns and meta-data */ + return srv_page_size / 8 * 3 + 512; + } + + /* Each record has page_no, length of page_no and header. */ + ulint comp = dict_table_is_comp(index->table); + ulint rec_max_size = comp + ? REC_NODE_PTR_SIZE + 1 + REC_N_NEW_EXTRA_BYTES + + UT_BITS_IN_BYTES(index->n_nullable) + : REC_NODE_PTR_SIZE + 2 + REC_N_OLD_EXTRA_BYTES + + 2 * index->n_fields; + + /* Compute the maximum possible record size. */ + for (ulint i = 0; i < dict_index_get_n_unique_in_tree(index); i++) { + const dict_field_t* field + = dict_index_get_nth_field(index, i); + const dict_col_t* col + = dict_field_get_col(field); + ulint field_max_size; + ulint field_ext_max_size; + + /* Determine the maximum length of the index field. */ + + field_max_size = dict_col_get_fixed_size(col, comp); + if (field_max_size) { + /* dict_index_add_col() should guarantee this */ + ut_ad(!field->prefix_len + || field->fixed_len == field->prefix_len); + /* Fixed lengths are not encoded + in ROW_FORMAT=COMPACT. */ + rec_max_size += field_max_size; + continue; + } + + field_max_size = dict_col_get_max_size(col); + if (UNIV_UNLIKELY(!field_max_size)) { + switch (col->mtype) { + case DATA_VARCHAR: + if (!comp + && (!strcmp(index->table->name.m_name, + "SYS_FOREIGN") + || !strcmp(index->table->name.m_name, + "SYS_FOREIGN_COLS"))) { + break; + } + /* fall through */ + case DATA_VARMYSQL: + case DATA_CHAR: + case DATA_MYSQL: + /* CHAR(0) and VARCHAR(0) are possible + data type definitions in MariaDB. + The InnoDB internal SQL parser maps + CHAR to DATA_VARCHAR, so DATA_CHAR (or + DATA_MYSQL) is only coming from the + MariaDB SQL layer. */ + if (comp) { + /* Add a length byte, because + fixed-length empty field are + encoded as variable-length. + For ROW_FORMAT=REDUNDANT, + these bytes were added to + rec_max_size before this loop. */ + rec_max_size++; + } + continue; + } + + /* SYS_FOREIGN.ID is defined as CHAR in the + InnoDB internal SQL parser, which translates + into the incorrect VARCHAR(0). InnoDB does + not enforce maximum lengths of columns, so + that is why any data can be inserted in the + first place. + + Likewise, SYS_FOREIGN.FOR_NAME, + SYS_FOREIGN.REF_NAME, SYS_FOREIGN_COLS.ID, are + defined as CHAR, and also they are part of a key. */ + + ut_ad(!strcmp(index->table->name.m_name, + "SYS_FOREIGN") + || !strcmp(index->table->name.m_name, + "SYS_FOREIGN_COLS")); + ut_ad(!comp); + ut_ad(col->mtype == DATA_VARCHAR); + + rec_max_size += (srv_page_size == UNIV_PAGE_SIZE_MAX) + ? REDUNDANT_REC_MAX_DATA_SIZE + : page_get_free_space_of_empty(FALSE) / 2; + } else if (field_max_size == NAME_LEN && i == 1 + && (!strcmp(index->table->name.m_name, + TABLE_STATS_NAME) + || !strcmp(index->table->name.m_name, + INDEX_STATS_NAME))) { + /* Interpret "table_name" as VARCHAR(199) even + if it was incorrectly defined as VARCHAR(64). + While the caller of ha_innobase enforces the + maximum length on any data written, the InnoDB + internal SQL parser will happily write as much + data as is provided. The purpose of this hack + is to avoid InnoDB hangs after persistent + statistics on partitioned tables are + deleted. */ + field_max_size = 199 * SYSTEM_CHARSET_MBMAXLEN; + } + field_ext_max_size = field_max_size < 256 ? 1 : 2; + + if (field->prefix_len + && field->prefix_len < field_max_size) { + field_max_size = field->prefix_len; + } + + if (comp) { + /* Add the extra size for ROW_FORMAT=COMPACT. + For ROW_FORMAT=REDUNDANT, these bytes were + added to rec_max_size before this loop. */ + rec_max_size += field_ext_max_size; + } + + rec_max_size += field_max_size; + } + + return rec_max_size; +} + +/********************************************************************//** +Searches an index tree and positions a tree cursor on a given level. +NOTE: n_fields_cmp in tuple must be set so that it cannot be compared +to node pointer page number fields on the upper levels of the tree! +Note that if mode is PAGE_CUR_LE, which is used in inserts, then +cursor->up_match and cursor->low_match both will have sensible values. +If mode is PAGE_CUR_GE, then up_match will a have a sensible value. + +If mode is PAGE_CUR_LE , cursor is left at the place where an insert of the +search tuple should be performed in the B-tree. InnoDB does an insert +immediately after the cursor. Thus, the cursor may end up on a user record, +or on a page infimum record. */ +dberr_t +btr_cur_search_to_nth_level_func( + dict_index_t* index, /*!< in: index */ + ulint level, /*!< in: the tree level of search */ + const dtuple_t* tuple, /*!< in: data tuple; NOTE: n_fields_cmp in + tuple must be set so that it cannot get + compared to the node ptr page number field! */ + page_cur_mode_t mode, /*!< in: PAGE_CUR_L, ...; + Inserts should always be made using + PAGE_CUR_LE to search the position! */ + ulint latch_mode, /*!< in: BTR_SEARCH_LEAF, ..., ORed with + at most one of BTR_INSERT, BTR_DELETE_MARK, + BTR_DELETE, or BTR_ESTIMATE; + cursor->left_block is used to store a pointer + to the left neighbor page, in the cases + BTR_SEARCH_PREV and BTR_MODIFY_PREV; + NOTE that if ahi_latch, we might not have a + cursor page latch, we assume that ahi_latch + protects the record! */ + btr_cur_t* cursor, /*!< in/out: tree cursor; the cursor page is + s- or x-latched, but see also above! */ +#ifdef BTR_CUR_HASH_ADAPT + rw_lock_t* ahi_latch, + /*!< in: currently held btr_search_latch + (in RW_S_LATCH mode), or NULL */ +#endif /* BTR_CUR_HASH_ADAPT */ + const char* file, /*!< in: file name */ + unsigned line, /*!< in: line where called */ + mtr_t* mtr, /*!< in: mtr */ + ib_uint64_t autoinc)/*!< in: PAGE_ROOT_AUTO_INC to be written + (0 if none) */ +{ + page_t* page = NULL; /* remove warning */ + buf_block_t* block; + buf_block_t* guess; + ulint height; + ulint up_match; + ulint up_bytes; + ulint low_match; + ulint low_bytes; + ulint rw_latch; + page_cur_mode_t page_mode; + page_cur_mode_t search_mode = PAGE_CUR_UNSUPP; + ulint buf_mode; + ulint estimate; + ulint node_ptr_max_size = srv_page_size / 2; + page_cur_t* page_cursor; + btr_op_t btr_op; + ulint root_height = 0; /* remove warning */ + dberr_t err = DB_SUCCESS; + + btr_intention_t lock_intention; + bool modify_external; + buf_block_t* tree_blocks[BTR_MAX_LEVELS]; + ulint tree_savepoints[BTR_MAX_LEVELS]; + ulint n_blocks = 0; + ulint n_releases = 0; + bool detected_same_key_root = false; + + bool retrying_for_search_prev = false; + ulint leftmost_from_level = 0; + buf_block_t** prev_tree_blocks = NULL; + ulint* prev_tree_savepoints = NULL; + ulint prev_n_blocks = 0; + ulint prev_n_releases = 0; + bool need_path = true; + bool rtree_parent_modified = false; + bool mbr_adj = false; + bool found = false; + + DBUG_ENTER("btr_cur_search_to_nth_level"); + +#ifdef BTR_CUR_ADAPT + btr_search_t* info; +#endif /* BTR_CUR_ADAPT */ + mem_heap_t* heap = NULL; + rec_offs offsets_[REC_OFFS_NORMAL_SIZE]; + rec_offs* offsets = offsets_; + rec_offs offsets2_[REC_OFFS_NORMAL_SIZE]; + rec_offs* offsets2 = offsets2_; + rec_offs_init(offsets_); + rec_offs_init(offsets2_); + /* Currently, PAGE_CUR_LE is the only search mode used for searches + ending to upper levels */ + + ut_ad(level == 0 || mode == PAGE_CUR_LE + || RTREE_SEARCH_MODE(mode)); + ut_ad(dict_index_check_search_tuple(index, tuple)); + ut_ad(!dict_index_is_ibuf(index) || ibuf_inside(mtr)); + ut_ad(dtuple_check_typed(tuple)); + ut_ad(!(index->type & DICT_FTS)); + ut_ad(index->page != FIL_NULL); + + MEM_UNDEFINED(&cursor->up_match, sizeof cursor->up_match); + MEM_UNDEFINED(&cursor->up_bytes, sizeof cursor->up_bytes); + MEM_UNDEFINED(&cursor->low_match, sizeof cursor->low_match); + MEM_UNDEFINED(&cursor->low_bytes, sizeof cursor->low_bytes); +#ifdef UNIV_DEBUG + cursor->up_match = ULINT_UNDEFINED; + cursor->low_match = ULINT_UNDEFINED; +#endif /* UNIV_DEBUG */ + + ibool s_latch_by_caller; + + s_latch_by_caller = latch_mode & BTR_ALREADY_S_LATCHED; + + ut_ad(!s_latch_by_caller + || srv_read_only_mode + || mtr->memo_contains_flagged(&index->lock, MTR_MEMO_S_LOCK + | MTR_MEMO_SX_LOCK)); + + /* These flags are mutually exclusive, they are lumped together + with the latch mode for historical reasons. It's possible for + none of the flags to be set. */ + switch (UNIV_EXPECT(latch_mode + & (BTR_INSERT | BTR_DELETE | BTR_DELETE_MARK), + 0)) { + case 0: + btr_op = BTR_NO_OP; + break; + case BTR_INSERT: + btr_op = (latch_mode & BTR_IGNORE_SEC_UNIQUE) + ? BTR_INSERT_IGNORE_UNIQUE_OP + : BTR_INSERT_OP; + break; + case BTR_DELETE: + btr_op = BTR_DELETE_OP; + ut_a(cursor->purge_node); + break; + case BTR_DELETE_MARK: + btr_op = BTR_DELMARK_OP; + break; + default: + /* only one of BTR_INSERT, BTR_DELETE, BTR_DELETE_MARK + should be specified at a time */ + ut_error; + } + + /* Operations on the insert buffer tree cannot be buffered. */ + ut_ad(btr_op == BTR_NO_OP || !dict_index_is_ibuf(index)); + /* Operations on the clustered index cannot be buffered. */ + ut_ad(btr_op == BTR_NO_OP || !dict_index_is_clust(index)); + /* Operations on the temporary table(indexes) cannot be buffered. */ + ut_ad(btr_op == BTR_NO_OP || !index->table->is_temporary()); + /* Operation on the spatial index cannot be buffered. */ + ut_ad(btr_op == BTR_NO_OP || !dict_index_is_spatial(index)); + + estimate = latch_mode & BTR_ESTIMATE; + + lock_intention = btr_cur_get_and_clear_intention(&latch_mode); + + modify_external = latch_mode & BTR_MODIFY_EXTERNAL; + + /* Turn the flags unrelated to the latch mode off. */ + latch_mode = BTR_LATCH_MODE_WITHOUT_FLAGS(latch_mode); + + ut_ad(!modify_external || latch_mode == BTR_MODIFY_LEAF); + + ut_ad(!s_latch_by_caller + || latch_mode == BTR_SEARCH_LEAF + || latch_mode == BTR_SEARCH_TREE + || latch_mode == BTR_MODIFY_LEAF); + + ut_ad(autoinc == 0 || dict_index_is_clust(index)); + ut_ad(autoinc == 0 + || latch_mode == BTR_MODIFY_TREE + || latch_mode == BTR_MODIFY_LEAF); + ut_ad(autoinc == 0 || level == 0); + + cursor->flag = BTR_CUR_BINARY; + cursor->index = index; + +#ifndef BTR_CUR_ADAPT + guess = NULL; +#else + info = btr_search_get_info(index); + guess = info->root_guess; + +#ifdef BTR_CUR_HASH_ADAPT + +# ifdef UNIV_SEARCH_PERF_STAT + info->n_searches++; +# endif + if (autoinc == 0 + && latch_mode <= BTR_MODIFY_LEAF + && info->last_hash_succ +# ifdef MYSQL_INDEX_DISABLE_AHI + && !index->disable_ahi +# endif + && !estimate +# ifdef PAGE_CUR_LE_OR_EXTENDS + && mode != PAGE_CUR_LE_OR_EXTENDS +# endif /* PAGE_CUR_LE_OR_EXTENDS */ + && !dict_index_is_spatial(index) + /* If !ahi_latch, we do a dirty read of + btr_search_enabled below, and btr_search_guess_on_hash() + will have to check it again. */ + && btr_search_enabled + && !modify_external + && !(tuple->info_bits & REC_INFO_MIN_REC_FLAG) + && btr_search_guess_on_hash(index, info, tuple, mode, + latch_mode, cursor, + ahi_latch, mtr)) { + + /* Search using the hash index succeeded */ + + ut_ad(cursor->up_match != ULINT_UNDEFINED + || mode != PAGE_CUR_GE); + ut_ad(cursor->up_match != ULINT_UNDEFINED + || mode != PAGE_CUR_LE); + ut_ad(cursor->low_match != ULINT_UNDEFINED + || mode != PAGE_CUR_LE); + btr_cur_n_sea++; + + DBUG_RETURN(err); + } +# endif /* BTR_CUR_HASH_ADAPT */ +#endif /* BTR_CUR_ADAPT */ + btr_cur_n_non_sea++; + + /* If the hash search did not succeed, do binary search down the + tree */ + +#ifdef BTR_CUR_HASH_ADAPT + if (ahi_latch) { + /* Release possible search latch to obey latching order */ + rw_lock_s_unlock(ahi_latch); + } +#endif /* BTR_CUR_HASH_ADAPT */ + + /* Store the position of the tree latch we push to mtr so that we + know how to release it when we have latched leaf node(s) */ + + ulint savepoint = mtr_set_savepoint(mtr); + + rw_lock_type_t upper_rw_latch; + + switch (latch_mode) { + case BTR_MODIFY_TREE: + /* Most of delete-intended operations are purging. + Free blocks and read IO bandwidth should be prior + for them, when the history list is glowing huge. */ + if (lock_intention == BTR_INTENTION_DELETE + && trx_sys.rseg_history_len > BTR_CUR_FINE_HISTORY_LENGTH + && buf_pool.n_pend_reads) { +x_latch_index: + mtr_x_lock_index(index, mtr); + } else if (index->is_spatial() + && lock_intention <= BTR_INTENTION_BOTH) { + /* X lock the if there is possibility of + pessimistic delete on spatial index. As we could + lock upward for the tree */ + goto x_latch_index; + } else { + mtr_sx_lock_index(index, mtr); + } + upper_rw_latch = RW_X_LATCH; + break; + case BTR_CONT_MODIFY_TREE: + case BTR_CONT_SEARCH_TREE: + /* Do nothing */ + ut_ad(srv_read_only_mode + || mtr->memo_contains_flagged(&index->lock, + MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + if (dict_index_is_spatial(index) + && latch_mode == BTR_CONT_MODIFY_TREE) { + /* If we are about to locating parent page for split + and/or merge operation for R-Tree index, X latch + the parent */ + upper_rw_latch = RW_X_LATCH; + } else { + upper_rw_latch = RW_NO_LATCH; + } + break; + default: + if (!srv_read_only_mode) { + if (s_latch_by_caller) { + ut_ad(rw_lock_own(dict_index_get_lock(index), + RW_LOCK_S)); + } else if (!modify_external) { + /* BTR_SEARCH_TREE is intended to be used with + BTR_ALREADY_S_LATCHED */ + ut_ad(latch_mode != BTR_SEARCH_TREE); + + mtr_s_lock_index(index, mtr); + } else { + /* BTR_MODIFY_EXTERNAL needs to be excluded */ + mtr_sx_lock_index(index, mtr); + } + upper_rw_latch = RW_S_LATCH; + } else { + upper_rw_latch = RW_NO_LATCH; + } + } + const rw_lock_type_t root_leaf_rw_latch = btr_cur_latch_for_root_leaf( + latch_mode); + + page_cursor = btr_cur_get_page_cur(cursor); + + const ulint zip_size = index->table->space->zip_size(); + + /* Start with the root page. */ + page_id_t page_id(index->table->space_id, index->page); + + if (root_leaf_rw_latch == RW_X_LATCH) { + node_ptr_max_size = btr_node_ptr_max_size(index); + } + + up_match = 0; + up_bytes = 0; + low_match = 0; + low_bytes = 0; + + height = ULINT_UNDEFINED; + + /* We use these modified search modes on non-leaf levels of the + B-tree. These let us end up in the right B-tree leaf. In that leaf + we use the original search mode. */ + + switch (mode) { + case PAGE_CUR_GE: + page_mode = PAGE_CUR_L; + break; + case PAGE_CUR_G: + page_mode = PAGE_CUR_LE; + break; + default: +#ifdef PAGE_CUR_LE_OR_EXTENDS + ut_ad(mode == PAGE_CUR_L || mode == PAGE_CUR_LE + || RTREE_SEARCH_MODE(mode) + || mode == PAGE_CUR_LE_OR_EXTENDS); +#else /* PAGE_CUR_LE_OR_EXTENDS */ + ut_ad(mode == PAGE_CUR_L || mode == PAGE_CUR_LE + || RTREE_SEARCH_MODE(mode)); +#endif /* PAGE_CUR_LE_OR_EXTENDS */ + page_mode = mode; + break; + } + + /* Loop and search until we arrive at the desired level */ + btr_latch_leaves_t latch_leaves = {{NULL, NULL, NULL}, {0, 0, 0}}; + +search_loop: + buf_mode = BUF_GET; + rw_latch = RW_NO_LATCH; + rtree_parent_modified = false; + + if (height != 0) { + /* We are about to fetch the root or a non-leaf page. */ + if ((latch_mode != BTR_MODIFY_TREE || height == level) + && !retrying_for_search_prev) { + /* If doesn't have SX or X latch of index, + each pages should be latched before reading. */ + if (height == ULINT_UNDEFINED + && upper_rw_latch == RW_S_LATCH + && (modify_external || autoinc)) { + /* needs sx-latch of root page + for fseg operation or for writing + PAGE_ROOT_AUTO_INC */ + rw_latch = RW_SX_LATCH; + } else { + rw_latch = upper_rw_latch; + } + } + } else if (latch_mode <= BTR_MODIFY_LEAF) { + rw_latch = latch_mode; + + if (btr_op != BTR_NO_OP + && ibuf_should_try(index, btr_op != BTR_INSERT_OP)) { + + /* Try to buffer the operation if the leaf + page is not in the buffer pool. */ + + buf_mode = btr_op == BTR_DELETE_OP + ? BUF_GET_IF_IN_POOL_OR_WATCH + : BUF_GET_IF_IN_POOL; + } + } + +retry_page_get: + ut_ad(n_blocks < BTR_MAX_LEVELS); + tree_savepoints[n_blocks] = mtr_set_savepoint(mtr); + block = buf_page_get_gen(page_id, zip_size, rw_latch, guess, + buf_mode, file, line, mtr, &err, + height == 0 && !index->is_clust()); + tree_blocks[n_blocks] = block; + + /* Note that block==NULL signifies either an error or change + buffering. */ + + if (err != DB_SUCCESS) { + ut_ad(block == NULL); + if (err == DB_DECRYPTION_FAILED) { + ib_push_warning((void *)NULL, + DB_DECRYPTION_FAILED, + "Table %s is encrypted but encryption service or" + " used key_id is not available. " + " Can't continue reading table.", + index->table->name.m_name); + index->table->file_unreadable = true; + } + + goto func_exit; + } + + if (block == NULL) { + /* This must be a search to perform an insert/delete + mark/ delete; try using the insert/delete buffer */ + + ut_ad(height == 0); + ut_ad(cursor->thr); + + switch (btr_op) { + case BTR_INSERT_OP: + case BTR_INSERT_IGNORE_UNIQUE_OP: + ut_ad(buf_mode == BUF_GET_IF_IN_POOL); + ut_ad(!dict_index_is_spatial(index)); + + if (ibuf_insert(IBUF_OP_INSERT, tuple, index, + page_id, zip_size, cursor->thr)) { + + cursor->flag = BTR_CUR_INSERT_TO_IBUF; + + goto func_exit; + } + break; + + case BTR_DELMARK_OP: + ut_ad(buf_mode == BUF_GET_IF_IN_POOL); + ut_ad(!dict_index_is_spatial(index)); + + if (ibuf_insert(IBUF_OP_DELETE_MARK, tuple, + index, page_id, zip_size, + cursor->thr)) { + + cursor->flag = BTR_CUR_DEL_MARK_IBUF; + + goto func_exit; + } + + break; + + case BTR_DELETE_OP: + ut_ad(buf_mode == BUF_GET_IF_IN_POOL_OR_WATCH); + ut_ad(!dict_index_is_spatial(index)); + + if (!row_purge_poss_sec(cursor->purge_node, + index, tuple)) { + + /* The record cannot be purged yet. */ + cursor->flag = BTR_CUR_DELETE_REF; + } else if (ibuf_insert(IBUF_OP_DELETE, tuple, + index, page_id, zip_size, + cursor->thr)) { + + /* The purge was buffered. */ + cursor->flag = BTR_CUR_DELETE_IBUF; + } else { + /* The purge could not be buffered. */ + buf_pool.watch_unset(page_id); + break; + } + + buf_pool.watch_unset(page_id); + goto func_exit; + + default: + ut_error; + } + + /* Insert to the insert/delete buffer did not succeed, we + must read the page from disk. */ + + buf_mode = BUF_GET; + + goto retry_page_get; + } + + if (retrying_for_search_prev && height != 0) { + /* also latch left sibling */ + uint32_t left_page_no; + buf_block_t* get_block; + + ut_ad(rw_latch == RW_NO_LATCH); + + rw_latch = upper_rw_latch; + + rw_lock_s_lock(&block->lock); + left_page_no = btr_page_get_prev(buf_block_get_frame(block)); + rw_lock_s_unlock(&block->lock); + + if (left_page_no != FIL_NULL) { + ut_ad(prev_n_blocks < leftmost_from_level); + + prev_tree_savepoints[prev_n_blocks] + = mtr_set_savepoint(mtr); + get_block = buf_page_get_gen( + page_id_t(page_id.space(), left_page_no), + zip_size, rw_latch, NULL, buf_mode, + file, line, mtr, &err); + prev_tree_blocks[prev_n_blocks] = get_block; + prev_n_blocks++; + + if (err != DB_SUCCESS) { + if (err == DB_DECRYPTION_FAILED) { + ib_push_warning((void *)NULL, + DB_DECRYPTION_FAILED, + "Table %s is encrypted but encryption service or" + " used key_id is not available. " + " Can't continue reading table.", + index->table->name.m_name); + index->table->file_unreadable = true; + } + + goto func_exit; + } + + /* BTR_MODIFY_TREE doesn't update prev/next_page_no, + without their parent page's lock. So, not needed to + retry here, because we have the parent page's lock. */ + } + + /* release RW_NO_LATCH page and lock with RW_S_LATCH */ + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_blocks], + tree_blocks[n_blocks]); + + tree_savepoints[n_blocks] = mtr_set_savepoint(mtr); + block = buf_page_get_gen(page_id, zip_size, + rw_latch, NULL, buf_mode, + file, line, mtr, &err); + tree_blocks[n_blocks] = block; + + if (err != DB_SUCCESS) { + if (err == DB_DECRYPTION_FAILED) { + ib_push_warning((void *)NULL, + DB_DECRYPTION_FAILED, + "Table %s is encrypted but encryption service or" + " used key_id is not available. " + " Can't continue reading table.", + index->table->name.m_name); + index->table->file_unreadable = true; + } + + goto func_exit; + } + } + + page = buf_block_get_frame(block); + + if (height == ULINT_UNDEFINED + && page_is_leaf(page) + && rw_latch != RW_NO_LATCH + && rw_latch != root_leaf_rw_latch) { + /* The root page is also a leaf page (root_leaf). + We should reacquire the page, because the root page + is latched differently from leaf pages. */ + ut_ad(root_leaf_rw_latch != RW_NO_LATCH); + ut_ad(rw_latch == RW_S_LATCH || rw_latch == RW_SX_LATCH); + ut_ad(rw_latch == RW_S_LATCH || modify_external || autoinc); + ut_ad(!autoinc || root_leaf_rw_latch == RW_X_LATCH); + + ut_ad(n_blocks == 0); + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_blocks], + tree_blocks[n_blocks]); + + upper_rw_latch = root_leaf_rw_latch; + goto search_loop; + } + + if (rw_latch != RW_NO_LATCH) { +#ifdef UNIV_ZIP_DEBUG + const page_zip_des_t* page_zip + = buf_block_get_page_zip(block); + ut_a(!page_zip || page_zip_validate(page_zip, page, index)); +#endif /* UNIV_ZIP_DEBUG */ + + buf_block_dbg_add_level( + block, dict_index_is_ibuf(index) + ? SYNC_IBUF_TREE_NODE : SYNC_TREE_NODE); + } + + ut_ad(fil_page_index_page_check(page)); + ut_ad(index->id == btr_page_get_index_id(page)); + + if (height == ULINT_UNDEFINED) { + /* We are in the root node */ + + height = btr_page_get_level(page); + root_height = height; + cursor->tree_height = root_height + 1; + + if (dict_index_is_spatial(index)) { + ut_ad(cursor->rtr_info); + + /* If SSN in memory is not initialized, fetch + it from root page */ + if (!rtr_get_current_ssn_id(index)) { + /* FIXME: do this in dict_load_table_one() */ + index->set_ssn(page_get_ssn_id(page) + 1); + } + + /* Save the MBR */ + cursor->rtr_info->thr = cursor->thr; + rtr_get_mbr_from_tuple(tuple, &cursor->rtr_info->mbr); + } + +#ifdef BTR_CUR_ADAPT + info->root_guess = block; +#endif + } + + if (height == 0) { + if (rw_latch == RW_NO_LATCH) { + latch_leaves = btr_cur_latch_leaves( + block, latch_mode, cursor, mtr); + } + + switch (latch_mode) { + case BTR_MODIFY_TREE: + case BTR_CONT_MODIFY_TREE: + case BTR_CONT_SEARCH_TREE: + break; + default: + if (!s_latch_by_caller + && !srv_read_only_mode + && !modify_external) { + /* Release the tree s-latch */ + /* NOTE: BTR_MODIFY_EXTERNAL + needs to keep tree sx-latch */ + mtr_release_s_latch_at_savepoint( + mtr, savepoint, + dict_index_get_lock(index)); + } + + /* release upper blocks */ + if (retrying_for_search_prev) { + ut_ad(!autoinc); + for (; + prev_n_releases < prev_n_blocks; + prev_n_releases++) { + mtr_release_block_at_savepoint( + mtr, + prev_tree_savepoints[ + prev_n_releases], + prev_tree_blocks[ + prev_n_releases]); + } + } + + for (; n_releases < n_blocks; n_releases++) { + if (n_releases == 0 + && (modify_external || autoinc)) { + /* keep the root page latch */ + ut_ad(mtr->memo_contains_flagged( + tree_blocks[n_releases], + MTR_MEMO_PAGE_SX_FIX + | MTR_MEMO_PAGE_X_FIX)); + continue; + } + + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + } + + page_mode = mode; + } + + if (dict_index_is_spatial(index)) { + /* Remember the page search mode */ + search_mode = page_mode; + + /* Some adjustment on search mode, when the + page search mode is PAGE_CUR_RTREE_LOCATE + or PAGE_CUR_RTREE_INSERT, as we are searching + with MBRs. When it is not the target level, we + should search all sub-trees that "CONTAIN" the + search range/MBR. When it is at the target + level, the search becomes PAGE_CUR_LE */ + if (page_mode == PAGE_CUR_RTREE_LOCATE + && level == height) { + if (level == 0) { + page_mode = PAGE_CUR_LE; + } else { + page_mode = PAGE_CUR_RTREE_GET_FATHER; + } + } + + if (page_mode == PAGE_CUR_RTREE_INSERT) { + page_mode = (level == height) + ? PAGE_CUR_LE + : PAGE_CUR_RTREE_INSERT; + + ut_ad(!page_is_leaf(page) || page_mode == PAGE_CUR_LE); + } + + /* "need_path" indicates if we need to tracking the parent + pages, if it is not spatial comparison, then no need to + track it */ + if (page_mode < PAGE_CUR_CONTAIN) { + need_path = false; + } + + up_match = 0; + low_match = 0; + + if (latch_mode == BTR_MODIFY_TREE + || latch_mode == BTR_CONT_MODIFY_TREE + || latch_mode == BTR_CONT_SEARCH_TREE) { + /* Tree are locked, no need for Page Lock to protect + the "path" */ + cursor->rtr_info->need_page_lock = false; + } + } + + if (dict_index_is_spatial(index) && page_mode >= PAGE_CUR_CONTAIN) { + ut_ad(need_path); + found = rtr_cur_search_with_match( + block, index, tuple, page_mode, page_cursor, + cursor->rtr_info); + + /* Need to use BTR_MODIFY_TREE to do the MBR adjustment */ + if (search_mode == PAGE_CUR_RTREE_INSERT + && cursor->rtr_info->mbr_adj) { + if (latch_mode & BTR_MODIFY_LEAF) { + /* Parent MBR needs updated, should retry + with BTR_MODIFY_TREE */ + goto func_exit; + } else if (latch_mode & BTR_MODIFY_TREE) { + rtree_parent_modified = true; + cursor->rtr_info->mbr_adj = false; + mbr_adj = true; + } else { + ut_ad(0); + } + } + + if (found && page_mode == PAGE_CUR_RTREE_GET_FATHER) { + cursor->low_match = + DICT_INDEX_SPATIAL_NODEPTR_SIZE + 1; + } +#ifdef BTR_CUR_HASH_ADAPT + } else if (height == 0 && btr_search_enabled + && !(tuple->info_bits & REC_INFO_MIN_REC_FLAG) + && !dict_index_is_spatial(index)) { + /* The adaptive hash index is only used when searching + for leaf pages (height==0), but not in r-trees. + We only need the byte prefix comparison for the purpose + of updating the adaptive hash index. */ + page_cur_search_with_match_bytes( + block, index, tuple, page_mode, &up_match, &up_bytes, + &low_match, &low_bytes, page_cursor); +#endif /* BTR_CUR_HASH_ADAPT */ + } else { + /* Search for complete index fields. */ + up_bytes = low_bytes = 0; + page_cur_search_with_match( + block, index, tuple, page_mode, &up_match, + &low_match, page_cursor, + need_path ? cursor->rtr_info : NULL); + } + + if (estimate) { + btr_cur_add_path_info(cursor, height, root_height); + } + + /* If this is the desired level, leave the loop */ + + ut_ad(height == btr_page_get_level(page_cur_get_page(page_cursor))); + + /* Add Predicate lock if it is serializable isolation + and only if it is in the search case */ + if (dict_index_is_spatial(index) + && cursor->rtr_info->need_prdt_lock + && mode != PAGE_CUR_RTREE_INSERT + && mode != PAGE_CUR_RTREE_LOCATE + && mode >= PAGE_CUR_CONTAIN) { + trx_t* trx = thr_get_trx(cursor->thr); + lock_prdt_t prdt; + + lock_mutex_enter(); + lock_init_prdt_from_mbr( + &prdt, &cursor->rtr_info->mbr, mode, + trx->lock.lock_heap); + lock_mutex_exit(); + + if (rw_latch == RW_NO_LATCH && height != 0) { + rw_lock_s_lock(&(block->lock)); + } + + lock_prdt_lock(block, &prdt, index, LOCK_S, + LOCK_PREDICATE, cursor->thr); + + if (rw_latch == RW_NO_LATCH && height != 0) { + rw_lock_s_unlock(&(block->lock)); + } + } + + if (level != height) { + + const rec_t* node_ptr; + ut_ad(height > 0); + + height--; + guess = NULL; + + node_ptr = page_cur_get_rec(page_cursor); + + offsets = rec_get_offsets(node_ptr, index, offsets, 0, + ULINT_UNDEFINED, &heap); + + /* If the rec is the first or last in the page for + pessimistic delete intention, it might cause node_ptr insert + for the upper level. We should change the intention and retry. + */ + if (latch_mode == BTR_MODIFY_TREE + && btr_cur_need_opposite_intention( + page, lock_intention, node_ptr)) { + +need_opposite_intention: + ut_ad(upper_rw_latch == RW_X_LATCH); + + if (n_releases > 0) { + /* release root block */ + mtr_release_block_at_savepoint( + mtr, tree_savepoints[0], + tree_blocks[0]); + } + + /* release all blocks */ + for (; n_releases <= n_blocks; n_releases++) { + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + + lock_intention = BTR_INTENTION_BOTH; + + page_id.set_page_no(index->page); + up_match = 0; + low_match = 0; + height = ULINT_UNDEFINED; + + n_blocks = 0; + n_releases = 0; + + goto search_loop; + } + + if (dict_index_is_spatial(index)) { + if (page_rec_is_supremum(node_ptr)) { + cursor->low_match = 0; + cursor->up_match = 0; + goto func_exit; + } + + /* If we are doing insertion or record locating, + remember the tree nodes we visited */ + if (page_mode == PAGE_CUR_RTREE_INSERT + || (search_mode == PAGE_CUR_RTREE_LOCATE + && (latch_mode != BTR_MODIFY_LEAF))) { + bool add_latch = false; + + if (latch_mode == BTR_MODIFY_TREE + && rw_latch == RW_NO_LATCH) { + ut_ad(mtr->memo_contains_flagged( + &index->lock, MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + rw_lock_s_lock(&block->lock); + add_latch = true; + } + + /* Store the parent cursor location */ +#ifdef UNIV_DEBUG + ulint num_stored = rtr_store_parent_path( + block, cursor, latch_mode, + height + 1, mtr); +#else + rtr_store_parent_path( + block, cursor, latch_mode, + height + 1, mtr); +#endif + + if (page_mode == PAGE_CUR_RTREE_INSERT) { + btr_pcur_t* r_cursor = + rtr_get_parent_cursor( + cursor, height + 1, + true); + /* If it is insertion, there should + be only one parent for each level + traverse */ +#ifdef UNIV_DEBUG + ut_ad(num_stored == 1); +#endif + + node_ptr = btr_pcur_get_rec(r_cursor); + + } + + if (add_latch) { + rw_lock_s_unlock(&block->lock); + } + + ut_ad(!page_rec_is_supremum(node_ptr)); + } + + ut_ad(page_mode == search_mode + || (page_mode == PAGE_CUR_WITHIN + && search_mode == PAGE_CUR_RTREE_LOCATE)); + + page_mode = search_mode; + } + + /* If the first or the last record of the page + or the same key value to the first record or last record, + the another page might be chosen when BTR_CONT_MODIFY_TREE. + So, the parent page should not released to avoiding deadlock + with blocking the another search with the same key value. */ + if (!detected_same_key_root + && lock_intention == BTR_INTENTION_BOTH + && !dict_index_is_unique(index) + && latch_mode == BTR_MODIFY_TREE + && (up_match >= rec_offs_n_fields(offsets) - 1 + || low_match >= rec_offs_n_fields(offsets) - 1)) { + const rec_t* first_rec = page_rec_get_next_const( + page_get_infimum_rec(page)); + ulint matched_fields; + + ut_ad(upper_rw_latch == RW_X_LATCH); + + if (node_ptr == first_rec + || page_rec_is_last(node_ptr, page)) { + detected_same_key_root = true; + } else { + matched_fields = 0; + + offsets2 = rec_get_offsets( + first_rec, index, offsets2, + 0, ULINT_UNDEFINED, &heap); + cmp_rec_rec(node_ptr, first_rec, + offsets, offsets2, index, false, + &matched_fields); + + if (matched_fields + >= rec_offs_n_fields(offsets) - 1) { + detected_same_key_root = true; + } else { + const rec_t* last_rec; + + last_rec = page_rec_get_prev_const( + page_get_supremum_rec(page)); + + matched_fields = 0; + + offsets2 = rec_get_offsets( + last_rec, index, offsets2, + 0, ULINT_UNDEFINED, &heap); + cmp_rec_rec( + node_ptr, last_rec, + offsets, offsets2, index, + false, &matched_fields); + if (matched_fields + >= rec_offs_n_fields(offsets) - 1) { + detected_same_key_root = true; + } + } + } + } + + /* If the page might cause modify_tree, + we should not release the parent page's lock. */ + if (!detected_same_key_root + && latch_mode == BTR_MODIFY_TREE + && !btr_cur_will_modify_tree( + index, page, lock_intention, node_ptr, + node_ptr_max_size, zip_size, mtr) + && !rtree_parent_modified) { + ut_ad(upper_rw_latch == RW_X_LATCH); + ut_ad(n_releases <= n_blocks); + + /* we can release upper blocks */ + for (; n_releases < n_blocks; n_releases++) { + if (n_releases == 0) { + /* we should not release root page + to pin to same block. */ + continue; + } + + /* release unused blocks to unpin */ + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + } + + if (height == level + && latch_mode == BTR_MODIFY_TREE) { + ut_ad(upper_rw_latch == RW_X_LATCH); + /* we should sx-latch root page, if released already. + It contains seg_header. */ + if (n_releases > 0) { + mtr_block_sx_latch_at_savepoint( + mtr, tree_savepoints[0], + tree_blocks[0]); + } + + /* x-latch the branch blocks not released yet. */ + for (ulint i = n_releases; i <= n_blocks; i++) { + mtr_block_x_latch_at_savepoint( + mtr, tree_savepoints[i], + tree_blocks[i]); + } + } + + /* We should consider prev_page of parent page, if the node_ptr + is the leftmost of the page. because BTR_SEARCH_PREV and + BTR_MODIFY_PREV latches prev_page of the leaf page. */ + if ((latch_mode == BTR_SEARCH_PREV + || latch_mode == BTR_MODIFY_PREV) + && !retrying_for_search_prev) { + /* block should be latched for consistent + btr_page_get_prev() */ + ut_ad(mtr->memo_contains_flagged( + block, MTR_MEMO_PAGE_S_FIX + | MTR_MEMO_PAGE_X_FIX)); + + if (page_has_prev(page) + && page_rec_is_first(node_ptr, page)) { + + if (leftmost_from_level == 0) { + leftmost_from_level = height + 1; + } + } else { + leftmost_from_level = 0; + } + + if (height == 0 && leftmost_from_level > 0) { + /* should retry to get also prev_page + from level==leftmost_from_level. */ + retrying_for_search_prev = true; + + prev_tree_blocks = static_cast<buf_block_t**>( + ut_malloc_nokey(sizeof(buf_block_t*) + * leftmost_from_level)); + + prev_tree_savepoints = static_cast<ulint*>( + ut_malloc_nokey(sizeof(ulint) + * leftmost_from_level)); + + /* back to the level (leftmost_from_level+1) */ + ulint idx = n_blocks + - (leftmost_from_level - 1); + + page_id.set_page_no( + tree_blocks[idx]->page.id().page_no()); + + for (ulint i = n_blocks + - (leftmost_from_level - 1); + i <= n_blocks; i++) { + mtr_release_block_at_savepoint( + mtr, tree_savepoints[i], + tree_blocks[i]); + } + + n_blocks -= (leftmost_from_level - 1); + height = leftmost_from_level; + ut_ad(n_releases == 0); + + /* replay up_match, low_match */ + up_match = 0; + low_match = 0; + rtr_info_t* rtr_info = need_path + ? cursor->rtr_info : NULL; + + for (ulint i = 0; i < n_blocks; i++) { + page_cur_search_with_match( + tree_blocks[i], index, tuple, + page_mode, &up_match, + &low_match, page_cursor, + rtr_info); + } + + goto search_loop; + } + } + + /* Go to the child node */ + page_id.set_page_no( + btr_node_ptr_get_child_page_no(node_ptr, offsets)); + + n_blocks++; + + if (UNIV_UNLIKELY(height == 0 && dict_index_is_ibuf(index))) { + /* We're doing a search on an ibuf tree and we're one + level above the leaf page. */ + + ut_ad(level == 0); + + buf_mode = BUF_GET; + rw_latch = RW_NO_LATCH; + goto retry_page_get; + } + + if (dict_index_is_spatial(index) + && page_mode >= PAGE_CUR_CONTAIN + && page_mode != PAGE_CUR_RTREE_INSERT) { + ut_ad(need_path); + rtr_node_path_t* path = + cursor->rtr_info->path; + + if (!path->empty() && found) { + ut_ad(path->back().page_no + == page_id.page_no()); + path->pop_back(); +#ifdef UNIV_DEBUG + if (page_mode == PAGE_CUR_RTREE_LOCATE + && (latch_mode != BTR_MODIFY_LEAF)) { + btr_pcur_t* cur + = cursor->rtr_info->parent_path->back( + ).cursor; + rec_t* my_node_ptr + = btr_pcur_get_rec(cur); + + offsets = rec_get_offsets( + my_node_ptr, index, offsets, + 0, ULINT_UNDEFINED, &heap); + + ulint my_page_no + = btr_node_ptr_get_child_page_no( + my_node_ptr, offsets); + + ut_ad(page_id.page_no() == my_page_no); + } +#endif + } + } + + goto search_loop; + } else if (!dict_index_is_spatial(index) + && latch_mode == BTR_MODIFY_TREE + && lock_intention == BTR_INTENTION_INSERT + && page_has_next(page) + && page_rec_is_last(page_cur_get_rec(page_cursor), page)) { + + /* btr_insert_into_right_sibling() might cause + deleting node_ptr at upper level */ + + guess = NULL; + + if (height == 0) { + /* release the leaf pages if latched */ + for (uint i = 0; i < 3; i++) { + if (latch_leaves.blocks[i] != NULL) { + mtr_release_block_at_savepoint( + mtr, latch_leaves.savepoints[i], + latch_leaves.blocks[i]); + latch_leaves.blocks[i] = NULL; + } + } + } + + goto need_opposite_intention; + } + + if (level != 0) { + ut_ad(!autoinc); + + if (upper_rw_latch == RW_NO_LATCH) { + ut_ad(latch_mode == BTR_CONT_MODIFY_TREE + || latch_mode == BTR_CONT_SEARCH_TREE); + buf_block_t* child_block = btr_block_get( + *index, page_id.page_no(), + latch_mode == BTR_CONT_MODIFY_TREE + ? RW_X_LATCH : RW_SX_LATCH, false, mtr); + btr_assert_not_corrupted(child_block, index); + } else { + ut_ad(mtr->memo_contains_flagged(block, + upper_rw_latch)); + btr_assert_not_corrupted(block, index); + + if (s_latch_by_caller) { + ut_ad(latch_mode == BTR_SEARCH_TREE); + /* to exclude modifying tree operations + should sx-latch the index. */ + ut_ad(mtr->memo_contains(index->lock, + MTR_MEMO_SX_LOCK)); + /* because has sx-latch of index, + can release upper blocks. */ + for (; n_releases < n_blocks; n_releases++) { + mtr_release_block_at_savepoint( + mtr, + tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + } + } + + if (page_mode <= PAGE_CUR_LE) { + cursor->low_match = low_match; + cursor->up_match = up_match; + } + } else { + cursor->low_match = low_match; + cursor->low_bytes = low_bytes; + cursor->up_match = up_match; + cursor->up_bytes = up_bytes; + + if (autoinc) { + page_set_autoinc(tree_blocks[0], autoinc, mtr, false); + } + +#ifdef BTR_CUR_HASH_ADAPT + /* We do a dirty read of btr_search_enabled here. We + will properly check btr_search_enabled again in + btr_search_build_page_hash_index() before building a + page hash index, while holding search latch. */ + if (!btr_search_enabled) { +# ifdef MYSQL_INDEX_DISABLE_AHI + } else if (index->disable_ahi) { +# endif + } else if (tuple->info_bits & REC_INFO_MIN_REC_FLAG) { + ut_ad(index->is_instant()); + /* This may be a search tuple for + btr_pcur_restore_position(). */ + ut_ad(tuple->is_metadata() + || (tuple->is_metadata(tuple->info_bits + ^ REC_STATUS_INSTANT))); + } else if (rec_is_metadata(btr_cur_get_rec(cursor), *index)) { + /* Only user records belong in the adaptive + hash index. */ + } else { + btr_search_info_update(index, cursor); + } +#endif /* BTR_CUR_HASH_ADAPT */ + ut_ad(cursor->up_match != ULINT_UNDEFINED + || mode != PAGE_CUR_GE); + ut_ad(cursor->up_match != ULINT_UNDEFINED + || mode != PAGE_CUR_LE); + ut_ad(cursor->low_match != ULINT_UNDEFINED + || mode != PAGE_CUR_LE); + } + + /* For spatial index, remember what blocks are still latched */ + if (dict_index_is_spatial(index) + && (latch_mode == BTR_MODIFY_TREE + || latch_mode == BTR_MODIFY_LEAF)) { + for (ulint i = 0; i < n_releases; i++) { + cursor->rtr_info->tree_blocks[i] = NULL; + cursor->rtr_info->tree_savepoints[i] = 0; + } + + for (ulint i = n_releases; i <= n_blocks; i++) { + cursor->rtr_info->tree_blocks[i] = tree_blocks[i]; + cursor->rtr_info->tree_savepoints[i] = tree_savepoints[i]; + } + } + +func_exit: + + if (UNIV_LIKELY_NULL(heap)) { + mem_heap_free(heap); + } + + if (retrying_for_search_prev) { + ut_free(prev_tree_blocks); + ut_free(prev_tree_savepoints); + } + + if (mbr_adj) { + /* remember that we will need to adjust parent MBR */ + cursor->rtr_info->mbr_adj = true; + } + +#ifdef BTR_CUR_HASH_ADAPT + if (ahi_latch) { + rw_lock_s_lock(ahi_latch); + } +#endif /* BTR_CUR_HASH_ADAPT */ + + DBUG_RETURN(err); +} + +/*****************************************************************//** +Opens a cursor at either end of an index. */ +dberr_t +btr_cur_open_at_index_side_func( +/*============================*/ + bool from_left, /*!< in: true if open to the low end, + false if to the high end */ + dict_index_t* index, /*!< in: index */ + ulint latch_mode, /*!< in: latch mode */ + btr_cur_t* cursor, /*!< in/out: cursor */ + ulint level, /*!< in: level to search for + (0=leaf). */ + const char* file, /*!< in: file name */ + unsigned line, /*!< in: line where called */ + mtr_t* mtr) /*!< in/out: mini-transaction */ +{ + page_cur_t* page_cursor; + ulint node_ptr_max_size = srv_page_size / 2; + ulint height; + ulint root_height = 0; /* remove warning */ + rec_t* node_ptr; + ulint estimate; + btr_intention_t lock_intention; + buf_block_t* tree_blocks[BTR_MAX_LEVELS]; + ulint tree_savepoints[BTR_MAX_LEVELS]; + ulint n_blocks = 0; + ulint n_releases = 0; + mem_heap_t* heap = NULL; + rec_offs offsets_[REC_OFFS_NORMAL_SIZE]; + rec_offs* offsets = offsets_; + dberr_t err = DB_SUCCESS; + + rec_offs_init(offsets_); + + estimate = latch_mode & BTR_ESTIMATE; + latch_mode &= ulint(~BTR_ESTIMATE); + + ut_ad(level != ULINT_UNDEFINED); + + bool s_latch_by_caller; + + s_latch_by_caller = latch_mode & BTR_ALREADY_S_LATCHED; + latch_mode &= ulint(~BTR_ALREADY_S_LATCHED); + + lock_intention = btr_cur_get_and_clear_intention(&latch_mode); + + ut_ad(!(latch_mode & BTR_MODIFY_EXTERNAL)); + + /* This function doesn't need to lock left page of the leaf page */ + if (latch_mode == BTR_SEARCH_PREV) { + latch_mode = BTR_SEARCH_LEAF; + } else if (latch_mode == BTR_MODIFY_PREV) { + latch_mode = BTR_MODIFY_LEAF; + } + + /* Store the position of the tree latch we push to mtr so that we + know how to release it when we have latched the leaf node */ + + ulint savepoint = mtr_set_savepoint(mtr); + + rw_lock_type_t upper_rw_latch; + + switch (latch_mode) { + case BTR_CONT_MODIFY_TREE: + case BTR_CONT_SEARCH_TREE: + upper_rw_latch = RW_NO_LATCH; + break; + case BTR_MODIFY_TREE: + /* Most of delete-intended operations are purging. + Free blocks and read IO bandwidth should be prior + for them, when the history list is glowing huge. */ + if (lock_intention == BTR_INTENTION_DELETE + && trx_sys.rseg_history_len > BTR_CUR_FINE_HISTORY_LENGTH + && buf_pool.n_pend_reads) { + mtr_x_lock_index(index, mtr); + } else { + mtr_sx_lock_index(index, mtr); + } + upper_rw_latch = RW_X_LATCH; + break; + default: + ut_ad(!s_latch_by_caller + || mtr->memo_contains_flagged(&index->lock, + MTR_MEMO_SX_LOCK + | MTR_MEMO_S_LOCK)); + if (!srv_read_only_mode) { + if (!s_latch_by_caller) { + /* BTR_SEARCH_TREE is intended to be used with + BTR_ALREADY_S_LATCHED */ + ut_ad(latch_mode != BTR_SEARCH_TREE); + + mtr_s_lock_index(index, mtr); + } + upper_rw_latch = RW_S_LATCH; + } else { + upper_rw_latch = RW_NO_LATCH; + } + } + + const rw_lock_type_t root_leaf_rw_latch = btr_cur_latch_for_root_leaf( + latch_mode); + + page_cursor = btr_cur_get_page_cur(cursor); + cursor->index = index; + + page_id_t page_id(index->table->space_id, index->page); + const ulint zip_size = index->table->space->zip_size(); + + if (root_leaf_rw_latch == RW_X_LATCH) { + node_ptr_max_size = btr_node_ptr_max_size(index); + } + + height = ULINT_UNDEFINED; + + for (;;) { + ut_ad(n_blocks < BTR_MAX_LEVELS); + tree_savepoints[n_blocks] = mtr_set_savepoint(mtr); + + const ulint rw_latch = height + && (latch_mode != BTR_MODIFY_TREE || height == level) + ? upper_rw_latch : RW_NO_LATCH; + buf_block_t* block = buf_page_get_gen(page_id, zip_size, + rw_latch, NULL, BUF_GET, + file, line, mtr, &err, + height == 0 + && !index->is_clust()); + ut_ad((block != NULL) == (err == DB_SUCCESS)); + tree_blocks[n_blocks] = block; + + if (err != DB_SUCCESS) { + if (err == DB_DECRYPTION_FAILED) { + ib_push_warning((void *)NULL, + DB_DECRYPTION_FAILED, + "Table %s is encrypted but encryption service or" + " used key_id is not available. " + " Can't continue reading table.", + index->table->name.m_name); + index->table->file_unreadable = true; + } + + goto exit_loop; + } + + const page_t* page = buf_block_get_frame(block); + + if (height == ULINT_UNDEFINED + && page_is_leaf(page) + && rw_latch != RW_NO_LATCH + && rw_latch != root_leaf_rw_latch) { + /* We should retry to get the page, because the root page + is latched with different level as a leaf page. */ + ut_ad(root_leaf_rw_latch != RW_NO_LATCH); + ut_ad(rw_latch == RW_S_LATCH); + + ut_ad(n_blocks == 0); + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_blocks], + tree_blocks[n_blocks]); + + upper_rw_latch = root_leaf_rw_latch; + continue; + } + + ut_ad(fil_page_index_page_check(page)); + ut_ad(index->id == btr_page_get_index_id(page)); + + if (height == ULINT_UNDEFINED) { + /* We are in the root node */ + + height = btr_page_get_level(page); + root_height = height; + ut_a(height >= level); + } else { + /* TODO: flag the index corrupted if this fails */ + ut_ad(height == btr_page_get_level(page)); + } + + if (height == 0) { + if (rw_latch == RW_NO_LATCH) { + btr_cur_latch_leaves(block, latch_mode, + cursor, mtr); + } + + /* In versions <= 3.23.52 we had forgotten to + release the tree latch here. If in an index + scan we had to scan far to find a record + visible to the current transaction, that could + starve others waiting for the tree latch. */ + + switch (latch_mode) { + case BTR_MODIFY_TREE: + case BTR_CONT_MODIFY_TREE: + case BTR_CONT_SEARCH_TREE: + break; + default: + if (UNIV_UNLIKELY(srv_read_only_mode)) { + break; + } + if (!s_latch_by_caller) { + /* Release the tree s-latch */ + mtr_release_s_latch_at_savepoint( + mtr, savepoint, &index->lock); + } + + /* release upper blocks */ + for (; n_releases < n_blocks; n_releases++) { + mtr_release_block_at_savepoint( + mtr, + tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + } + } else if (height == level /* height != 0 */ + && UNIV_LIKELY(!srv_read_only_mode)) { + /* We already have the block latched. */ + ut_ad(latch_mode == BTR_SEARCH_TREE); + ut_ad(s_latch_by_caller); + ut_ad(upper_rw_latch == RW_S_LATCH); + ut_ad(mtr->memo_contains_flagged(block, + MTR_MEMO_PAGE_S_FIX)); + + if (s_latch_by_caller) { + /* to exclude modifying tree operations + should sx-latch the index. */ + ut_ad(mtr->memo_contains(index->lock, + MTR_MEMO_SX_LOCK)); + /* because has sx-latch of index, + can release upper blocks. */ + for (; n_releases < n_blocks; n_releases++) { + mtr_release_block_at_savepoint( + mtr, + tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + } + } + + if (from_left) { + page_cur_set_before_first(block, page_cursor); + } else { + page_cur_set_after_last(block, page_cursor); + } + + if (height == level) { + if (estimate) { + btr_cur_add_path_info(cursor, height, + root_height); + } + + break; + } + + ut_ad(height > 0); + + if (from_left) { + page_cur_move_to_next(page_cursor); + } else { + page_cur_move_to_prev(page_cursor); + } + + if (estimate) { + btr_cur_add_path_info(cursor, height, root_height); + } + + height--; + + node_ptr = page_cur_get_rec(page_cursor); + offsets = rec_get_offsets(node_ptr, cursor->index, offsets, + 0, ULINT_UNDEFINED, &heap); + + /* If the rec is the first or last in the page for + pessimistic delete intention, it might cause node_ptr insert + for the upper level. We should change the intention and retry. + */ + if (latch_mode == BTR_MODIFY_TREE + && btr_cur_need_opposite_intention( + page, lock_intention, node_ptr)) { + + ut_ad(upper_rw_latch == RW_X_LATCH); + /* release all blocks */ + for (; n_releases <= n_blocks; n_releases++) { + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + + lock_intention = BTR_INTENTION_BOTH; + + page_id.set_page_no(dict_index_get_page(index)); + + height = ULINT_UNDEFINED; + + n_blocks = 0; + n_releases = 0; + + continue; + } + + if (latch_mode == BTR_MODIFY_TREE + && !btr_cur_will_modify_tree( + cursor->index, page, lock_intention, node_ptr, + node_ptr_max_size, zip_size, mtr)) { + ut_ad(upper_rw_latch == RW_X_LATCH); + ut_ad(n_releases <= n_blocks); + + /* we can release upper blocks */ + for (; n_releases < n_blocks; n_releases++) { + if (n_releases == 0) { + /* we should not release root page + to pin to same block. */ + continue; + } + + /* release unused blocks to unpin */ + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + } + + if (height == level + && latch_mode == BTR_MODIFY_TREE) { + ut_ad(upper_rw_latch == RW_X_LATCH); + /* we should sx-latch root page, if released already. + It contains seg_header. */ + if (n_releases > 0) { + mtr_block_sx_latch_at_savepoint( + mtr, tree_savepoints[0], + tree_blocks[0]); + } + + /* x-latch the branch blocks not released yet. */ + for (ulint i = n_releases; i <= n_blocks; i++) { + mtr_block_x_latch_at_savepoint( + mtr, tree_savepoints[i], + tree_blocks[i]); + } + } + + /* Go to the child node */ + page_id.set_page_no( + btr_node_ptr_get_child_page_no(node_ptr, offsets)); + + n_blocks++; + } + + exit_loop: + if (heap) { + mem_heap_free(heap); + } + + return err; +} + +/**********************************************************************//** +Positions a cursor at a randomly chosen position within a B-tree. +@return true if the index is available and we have put the cursor, false +if the index is unavailable */ +bool +btr_cur_open_at_rnd_pos_func( +/*=========================*/ + dict_index_t* index, /*!< in: index */ + ulint latch_mode, /*!< in: BTR_SEARCH_LEAF, ... */ + btr_cur_t* cursor, /*!< in/out: B-tree cursor */ + const char* file, /*!< in: file name */ + unsigned line, /*!< in: line where called */ + mtr_t* mtr) /*!< in: mtr */ +{ + page_cur_t* page_cursor; + ulint node_ptr_max_size = srv_page_size / 2; + ulint height; + rec_t* node_ptr; + btr_intention_t lock_intention; + buf_block_t* tree_blocks[BTR_MAX_LEVELS]; + ulint tree_savepoints[BTR_MAX_LEVELS]; + ulint n_blocks = 0; + ulint n_releases = 0; + mem_heap_t* heap = NULL; + rec_offs offsets_[REC_OFFS_NORMAL_SIZE]; + rec_offs* offsets = offsets_; + rec_offs_init(offsets_); + + ut_ad(!index->is_spatial()); + + lock_intention = btr_cur_get_and_clear_intention(&latch_mode); + + ut_ad(!(latch_mode & BTR_MODIFY_EXTERNAL)); + + ulint savepoint = mtr_set_savepoint(mtr); + + rw_lock_type_t upper_rw_latch; + + switch (latch_mode) { + case BTR_MODIFY_TREE: + /* Most of delete-intended operations are purging. + Free blocks and read IO bandwidth should be prior + for them, when the history list is glowing huge. */ + if (lock_intention == BTR_INTENTION_DELETE + && trx_sys.rseg_history_len > BTR_CUR_FINE_HISTORY_LENGTH + && buf_pool.n_pend_reads) { + mtr_x_lock_index(index, mtr); + } else { + mtr_sx_lock_index(index, mtr); + } + upper_rw_latch = RW_X_LATCH; + break; + case BTR_SEARCH_PREV: + case BTR_MODIFY_PREV: + /* This function doesn't support left uncle + page lock for left leaf page lock, when + needed. */ + case BTR_SEARCH_TREE: + case BTR_CONT_MODIFY_TREE: + case BTR_CONT_SEARCH_TREE: + ut_ad(0); + /* fall through */ + default: + if (!srv_read_only_mode) { + mtr_s_lock_index(index, mtr); + upper_rw_latch = RW_S_LATCH; + } else { + upper_rw_latch = RW_NO_LATCH; + } + } + + DBUG_EXECUTE_IF("test_index_is_unavailable", + return(false);); + + if (index->page == FIL_NULL) { + /* Since we don't hold index lock until just now, the index + could be modified by others, for example, if this is a + statistics updater for referenced table, it could be marked + as unavailable by 'DROP TABLE' in the mean time, since + we don't hold lock for statistics updater */ + return(false); + } + + const rw_lock_type_t root_leaf_rw_latch = btr_cur_latch_for_root_leaf( + latch_mode); + + page_cursor = btr_cur_get_page_cur(cursor); + cursor->index = index; + + page_id_t page_id(index->table->space_id, index->page); + const ulint zip_size = index->table->space->zip_size(); + dberr_t err = DB_SUCCESS; + + if (root_leaf_rw_latch == RW_X_LATCH) { + node_ptr_max_size = btr_node_ptr_max_size(index); + } + + height = ULINT_UNDEFINED; + + for (;;) { + page_t* page; + + ut_ad(n_blocks < BTR_MAX_LEVELS); + tree_savepoints[n_blocks] = mtr_set_savepoint(mtr); + + const rw_lock_type_t rw_latch = height + && latch_mode != BTR_MODIFY_TREE + ? upper_rw_latch : RW_NO_LATCH; + buf_block_t* block = buf_page_get_gen(page_id, zip_size, + rw_latch, NULL, BUF_GET, + file, line, mtr, &err, + height == 0 + && !index->is_clust()); + tree_blocks[n_blocks] = block; + + ut_ad((block != NULL) == (err == DB_SUCCESS)); + + if (err != DB_SUCCESS) { + if (err == DB_DECRYPTION_FAILED) { + ib_push_warning((void *)NULL, + DB_DECRYPTION_FAILED, + "Table %s is encrypted but encryption service or" + " used key_id is not available. " + " Can't continue reading table.", + index->table->name.m_name); + index->table->file_unreadable = true; + } + + break; + } + + page = buf_block_get_frame(block); + + if (height == ULINT_UNDEFINED + && page_is_leaf(page) + && rw_latch != RW_NO_LATCH + && rw_latch != root_leaf_rw_latch) { + /* We should retry to get the page, because the root page + is latched with different level as a leaf page. */ + ut_ad(root_leaf_rw_latch != RW_NO_LATCH); + ut_ad(rw_latch == RW_S_LATCH); + + ut_ad(n_blocks == 0); + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_blocks], + tree_blocks[n_blocks]); + + upper_rw_latch = root_leaf_rw_latch; + continue; + } + + ut_ad(fil_page_index_page_check(page)); + ut_ad(index->id == btr_page_get_index_id(page)); + + if (height == ULINT_UNDEFINED) { + /* We are in the root node */ + + height = btr_page_get_level(page); + } + + if (height == 0) { + if (rw_latch == RW_NO_LATCH + || srv_read_only_mode) { + btr_cur_latch_leaves(block, latch_mode, cursor, + mtr); + } + + /* btr_cur_open_at_index_side_func() and + btr_cur_search_to_nth_level() release + tree s-latch here.*/ + switch (latch_mode) { + case BTR_MODIFY_TREE: + case BTR_CONT_MODIFY_TREE: + case BTR_CONT_SEARCH_TREE: + break; + default: + /* Release the tree s-latch */ + if (!srv_read_only_mode) { + mtr_release_s_latch_at_savepoint( + mtr, savepoint, + dict_index_get_lock(index)); + } + + /* release upper blocks */ + for (; n_releases < n_blocks; n_releases++) { + mtr_release_block_at_savepoint( + mtr, + tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + } + } + + page_cur_open_on_rnd_user_rec(block, page_cursor); + + if (height == 0) { + + break; + } + + ut_ad(height > 0); + + height--; + + node_ptr = page_cur_get_rec(page_cursor); + offsets = rec_get_offsets(node_ptr, cursor->index, offsets, + 0, ULINT_UNDEFINED, &heap); + + /* If the rec is the first or last in the page for + pessimistic delete intention, it might cause node_ptr insert + for the upper level. We should change the intention and retry. + */ + if (latch_mode == BTR_MODIFY_TREE + && btr_cur_need_opposite_intention( + page, lock_intention, node_ptr)) { + + ut_ad(upper_rw_latch == RW_X_LATCH); + /* release all blocks */ + for (; n_releases <= n_blocks; n_releases++) { + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + + lock_intention = BTR_INTENTION_BOTH; + + page_id.set_page_no(dict_index_get_page(index)); + + height = ULINT_UNDEFINED; + + n_blocks = 0; + n_releases = 0; + + continue; + } + + if (latch_mode == BTR_MODIFY_TREE + && !btr_cur_will_modify_tree( + cursor->index, page, lock_intention, node_ptr, + node_ptr_max_size, zip_size, mtr)) { + ut_ad(upper_rw_latch == RW_X_LATCH); + ut_ad(n_releases <= n_blocks); + + /* we can release upper blocks */ + for (; n_releases < n_blocks; n_releases++) { + if (n_releases == 0) { + /* we should not release root page + to pin to same block. */ + continue; + } + + /* release unused blocks to unpin */ + mtr_release_block_at_savepoint( + mtr, tree_savepoints[n_releases], + tree_blocks[n_releases]); + } + } + + if (height == 0 + && latch_mode == BTR_MODIFY_TREE) { + ut_ad(upper_rw_latch == RW_X_LATCH); + /* we should sx-latch root page, if released already. + It contains seg_header. */ + if (n_releases > 0) { + mtr_block_sx_latch_at_savepoint( + mtr, tree_savepoints[0], + tree_blocks[0]); + } + + /* x-latch the branch blocks not released yet. */ + for (ulint i = n_releases; i <= n_blocks; i++) { + mtr_block_x_latch_at_savepoint( + mtr, tree_savepoints[i], + tree_blocks[i]); + } + } + + /* Go to the child node */ + page_id.set_page_no( + btr_node_ptr_get_child_page_no(node_ptr, offsets)); + + n_blocks++; + } + + if (UNIV_LIKELY_NULL(heap)) { + mem_heap_free(heap); + } + + return err == DB_SUCCESS; +} + +/*==================== B-TREE INSERT =========================*/ + +/*************************************************************//** +Inserts a record if there is enough space, or if enough space can +be freed by reorganizing. Differs from btr_cur_optimistic_insert because +no heuristics is applied to whether it pays to use CPU time for +reorganizing the page or not. + +IMPORTANT: The caller will have to update IBUF_BITMAP_FREE +if this is a compressed leaf page in a secondary index. +This has to be done either within the same mini-transaction, +or by invoking ibuf_reset_free_bits() before mtr_commit(). + +@return pointer to inserted record if succeed, else NULL */ +static MY_ATTRIBUTE((nonnull, warn_unused_result)) +rec_t* +btr_cur_insert_if_possible( +/*=======================*/ + btr_cur_t* cursor, /*!< in: cursor on page after which to insert; + cursor stays valid */ + const dtuple_t* tuple, /*!< in: tuple to insert; the size info need not + have been stored to tuple */ + rec_offs** offsets,/*!< out: offsets on *rec */ + mem_heap_t** heap, /*!< in/out: pointer to memory heap, or NULL */ + ulint n_ext, /*!< in: number of externally stored columns */ + mtr_t* mtr) /*!< in/out: mini-transaction */ +{ + page_cur_t* page_cursor; + rec_t* rec; + + ut_ad(dtuple_check_typed(tuple)); + + ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(cursor), + MTR_MEMO_PAGE_X_FIX)); + page_cursor = btr_cur_get_page_cur(cursor); + + /* Now, try the insert */ + rec = page_cur_tuple_insert(page_cursor, tuple, cursor->index, + offsets, heap, n_ext, mtr); + + /* If the record did not fit, reorganize. + For compressed pages, page_cur_tuple_insert() + attempted this already. */ + if (!rec && !page_cur_get_page_zip(page_cursor) + && btr_page_reorganize(page_cursor, cursor->index, mtr)) { + rec = page_cur_tuple_insert( + page_cursor, tuple, cursor->index, + offsets, heap, n_ext, mtr); + } + + ut_ad(!rec || rec_offs_validate(rec, cursor->index, *offsets)); + return(rec); +} + +/*************************************************************//** +For an insert, checks the locks and does the undo logging if desired. +@return DB_SUCCESS, DB_WAIT_LOCK, DB_FAIL, or error number */ +UNIV_INLINE MY_ATTRIBUTE((warn_unused_result, nonnull(2,3,5,6))) +dberr_t +btr_cur_ins_lock_and_undo( +/*======================*/ + ulint flags, /*!< in: undo logging and locking flags: if + not zero, the parameters index and thr + should be specified */ + btr_cur_t* cursor, /*!< in: cursor on page after which to insert */ + dtuple_t* entry, /*!< in/out: entry to insert */ + que_thr_t* thr, /*!< in: query thread or NULL */ + mtr_t* mtr, /*!< in/out: mini-transaction */ + bool* inherit)/*!< out: true if the inserted new record maybe + should inherit LOCK_GAP type locks from the + successor record */ +{ + dict_index_t* index; + dberr_t err = DB_SUCCESS; + rec_t* rec; + roll_ptr_t roll_ptr; + + /* Check if we have to wait for a lock: enqueue an explicit lock + request if yes */ + + rec = btr_cur_get_rec(cursor); + index = cursor->index; + + ut_ad(!dict_index_is_online_ddl(index) + || dict_index_is_clust(index) + || (flags & BTR_CREATE_FLAG)); + ut_ad(mtr->is_named_space(index->table->space)); + + /* Check if there is predicate or GAP lock preventing the insertion */ + if (!(flags & BTR_NO_LOCKING_FLAG)) { + const unsigned type = index->type; + if (UNIV_UNLIKELY(type & DICT_SPATIAL)) { + lock_prdt_t prdt; + rtr_mbr_t mbr; + + rtr_get_mbr_from_tuple(entry, &mbr); + + /* Use on stack MBR variable to test if a lock is + needed. If so, the predicate (MBR) will be allocated + from lock heap in lock_prdt_insert_check_and_lock() */ + lock_init_prdt_from_mbr( + &prdt, &mbr, 0, NULL); + + err = lock_prdt_insert_check_and_lock( + flags, rec, btr_cur_get_block(cursor), + index, thr, mtr, &prdt); + *inherit = false; + } else { +#ifdef WITH_WSREP + trx_t* trx= thr_get_trx(thr); + /* If transaction scanning an unique secondary + key is wsrep high priority thread (brute + force) this scanning may involve GAP-locking + in the index. As this locking happens also + when applying replication events in high + priority applier threads, there is a + probability for lock conflicts between two + wsrep high priority threads. To avoid this + GAP-locking we mark that this transaction + is using unique key scan here. */ + if ((type & (DICT_CLUSTERED | DICT_UNIQUE)) == DICT_UNIQUE + && trx->is_wsrep() + && wsrep_thd_is_BF(trx->mysql_thd, false)) { + trx->wsrep_UK_scan= true; + } +#endif /* WITH_WSREP */ + err = lock_rec_insert_check_and_lock( + flags, rec, btr_cur_get_block(cursor), + index, thr, mtr, inherit); +#ifdef WITH_WSREP + trx->wsrep_UK_scan= false; +#endif /* WITH_WSREP */ + } + } + + if (err != DB_SUCCESS + || !(~flags | (BTR_NO_UNDO_LOG_FLAG | BTR_KEEP_SYS_FLAG)) + || !dict_index_is_clust(index) || dict_index_is_ibuf(index)) { + + return(err); + } + + if (flags & BTR_NO_UNDO_LOG_FLAG) { + roll_ptr = roll_ptr_t(1) << ROLL_PTR_INSERT_FLAG_POS; + if (!(flags & BTR_KEEP_SYS_FLAG)) { +upd_sys: + dfield_t* r = dtuple_get_nth_field( + entry, index->db_roll_ptr()); + ut_ad(r->len == DATA_ROLL_PTR_LEN); + trx_write_roll_ptr(static_cast<byte*>(r->data), + roll_ptr); + } + } else { + err = trx_undo_report_row_operation(thr, index, entry, + NULL, 0, NULL, NULL, + &roll_ptr); + if (err == DB_SUCCESS) { + goto upd_sys; + } + } + + return(err); +} + +/** +Prefetch siblings of the leaf for the pessimistic operation. +@param block leaf page +@param index index of the page */ +static void btr_cur_prefetch_siblings(const buf_block_t *block, + const dict_index_t *index) +{ + ut_ad(page_is_leaf(block->frame)); + + if (index->is_ibuf()) + return; + + const page_t *page= block->frame; + uint32_t prev= mach_read_from_4(my_assume_aligned<4>(page + FIL_PAGE_PREV)); + uint32_t next= mach_read_from_4(my_assume_aligned<4>(page + FIL_PAGE_NEXT)); + + if (prev == FIL_NULL); + else if (index->table->space->acquire()) + buf_read_page_background(index->table->space, + page_id_t(block->page.id().space(), prev), + block->zip_size(), false); + if (next == FIL_NULL); + else if (index->table->space->acquire()) + buf_read_page_background(index->table->space, + page_id_t(block->page.id().space(), next), + block->zip_size(), false); +} + +/*************************************************************//** +Tries to perform an insert to a page in an index tree, next to cursor. +It is assumed that mtr holds an x-latch on the page. The operation does +not succeed if there is too little space on the page. If there is just +one record on the page, the insert will always succeed; this is to +prevent trying to split a page with just one record. +@return DB_SUCCESS, DB_WAIT_LOCK, DB_FAIL, or error number */ +dberr_t +btr_cur_optimistic_insert( +/*======================*/ + ulint flags, /*!< in: undo logging and locking flags: if not + zero, the parameters index and thr should be + specified */ + btr_cur_t* cursor, /*!< in: cursor on page after which to insert; + cursor stays valid */ + rec_offs** offsets,/*!< out: offsets on *rec */ + mem_heap_t** heap, /*!< in/out: pointer to memory heap */ + dtuple_t* entry, /*!< in/out: entry to insert */ + rec_t** rec, /*!< out: pointer to inserted record if + succeed */ + big_rec_t** big_rec,/*!< out: big rec vector whose fields have to + be stored externally by the caller */ + ulint n_ext, /*!< in: number of externally stored columns */ + que_thr_t* thr, /*!< in/out: query thread; can be NULL if + !(~flags + & (BTR_NO_LOCKING_FLAG + | BTR_NO_UNDO_LOG_FLAG)) */ + mtr_t* mtr) /*!< in/out: mini-transaction; + if this function returns DB_SUCCESS on + a leaf page of a secondary index in a + compressed tablespace, the caller must + mtr_commit(mtr) before latching + any further pages */ +{ + big_rec_t* big_rec_vec = NULL; + dict_index_t* index; + page_cur_t* page_cursor; + buf_block_t* block; + page_t* page; + rec_t* dummy; + bool leaf; + bool reorg __attribute__((unused)); + bool inherit = true; + ulint rec_size; + dberr_t err; + + ut_ad(thr || !(~flags & (BTR_NO_LOCKING_FLAG | BTR_NO_UNDO_LOG_FLAG))); + *big_rec = NULL; + + block = btr_cur_get_block(cursor); + page = buf_block_get_frame(block); + index = cursor->index; + + ut_ad(mtr->memo_contains_flagged(block, MTR_MEMO_PAGE_X_FIX)); + ut_ad(!dict_index_is_online_ddl(index) + || dict_index_is_clust(index) + || (flags & BTR_CREATE_FLAG)); + ut_ad(dtuple_check_typed(entry)); + +#ifdef HAVE_valgrind + if (block->page.zip.data) { + MEM_CHECK_DEFINED(page, srv_page_size); + MEM_CHECK_DEFINED(block->page.zip.data, block->zip_size()); + } +#endif /* HAVE_valgrind */ + + leaf = page_is_leaf(page); + + if (UNIV_UNLIKELY(entry->is_alter_metadata())) { + ut_ad(leaf); + goto convert_big_rec; + } + + /* Calculate the record size when entry is converted to a record */ + rec_size = rec_get_converted_size(index, entry, n_ext); + + if (page_zip_rec_needs_ext(rec_size, page_is_comp(page), + dtuple_get_n_fields(entry), + block->zip_size())) { +convert_big_rec: + /* The record is so big that we have to store some fields + externally on separate database pages */ + big_rec_vec = dtuple_convert_big_rec(index, 0, entry, &n_ext); + + if (UNIV_UNLIKELY(big_rec_vec == NULL)) { + + return(DB_TOO_BIG_RECORD); + } + + rec_size = rec_get_converted_size(index, entry, n_ext); + } + + if (block->page.zip.data && page_zip_is_too_big(index, entry)) { + if (big_rec_vec != NULL) { + dtuple_convert_back_big_rec(index, entry, big_rec_vec); + } + + return(DB_TOO_BIG_RECORD); + } + + LIMIT_OPTIMISTIC_INSERT_DEBUG(page_get_n_recs(page), + goto fail); + + if (block->page.zip.data && leaf + && (page_get_data_size(page) + rec_size + >= dict_index_zip_pad_optimal_page_size(index))) { + /* If compression padding tells us that insertion will + result in too packed up page i.e.: which is likely to + cause compression failure then don't do an optimistic + insertion. */ +fail: + err = DB_FAIL; + + /* prefetch siblings of the leaf for the pessimistic + operation, if the page is leaf. */ + if (page_is_leaf(page)) { + btr_cur_prefetch_siblings(block, index); + } +fail_err: + + if (big_rec_vec) { + dtuple_convert_back_big_rec(index, entry, big_rec_vec); + } + + return(err); + } + + ulint max_size = page_get_max_insert_size_after_reorganize(page, 1); + if (max_size < rec_size) { + goto fail; + } + + const ulint n_recs = page_get_n_recs(page); + if (UNIV_UNLIKELY(n_recs >= 8189)) { + ut_ad(srv_page_size == 65536); + goto fail; + } + + if (page_has_garbage(page)) { + if (max_size < BTR_CUR_PAGE_REORGANIZE_LIMIT + && n_recs > 1 + && page_get_max_insert_size(page, 1) < rec_size) { + + goto fail; + } + } + + /* If there have been many consecutive inserts to the + clustered index leaf page of an uncompressed table, check if + we have to split the page to reserve enough free space for + future updates of records. */ + + if (leaf && !block->page.zip.data && dict_index_is_clust(index) + && page_get_n_recs(page) >= 2 + && dict_index_get_space_reserve() + rec_size > max_size + && (btr_page_get_split_rec_to_right(cursor, &dummy) + || btr_page_get_split_rec_to_left(cursor))) { + goto fail; + } + + page_cursor = btr_cur_get_page_cur(cursor); + + DBUG_LOG("ib_cur", + "insert " << index->name << " (" << index->id << ") by " + << ib::hex(thr ? thr->graph->trx->id : 0) + << ' ' << rec_printer(entry).str()); + DBUG_EXECUTE_IF("do_page_reorganize", + btr_page_reorganize(page_cursor, index, mtr);); + + /* Now, try the insert */ + { + const rec_t* page_cursor_rec = page_cur_get_rec(page_cursor); + + /* Check locks and write to the undo log, + if specified */ + err = btr_cur_ins_lock_and_undo(flags, cursor, entry, + thr, mtr, &inherit); + if (err != DB_SUCCESS) { + goto fail_err; + } + +#ifdef UNIV_DEBUG + if (!(flags & BTR_CREATE_FLAG) + && index->is_primary() && page_is_leaf(page)) { + const dfield_t* trx_id = dtuple_get_nth_field( + entry, dict_col_get_clust_pos( + dict_table_get_sys_col(index->table, + DATA_TRX_ID), + index)); + + ut_ad(trx_id->len == DATA_TRX_ID_LEN); + ut_ad(trx_id[1].len == DATA_ROLL_PTR_LEN); + ut_ad(*static_cast<const byte*> + (trx_id[1].data) & 0x80); + if (flags & BTR_NO_UNDO_LOG_FLAG) { + ut_ad(!memcmp(trx_id->data, reset_trx_id, + DATA_TRX_ID_LEN)); + } else { + ut_ad(thr->graph->trx->id); + ut_ad(thr->graph->trx->id + == trx_read_trx_id( + static_cast<const byte*>( + trx_id->data)) + || index->table->is_temporary()); + } + } +#endif + + *rec = page_cur_tuple_insert( + page_cursor, entry, index, offsets, heap, + n_ext, mtr); + + reorg = page_cursor_rec != page_cur_get_rec(page_cursor); + } + + if (*rec) { + } else if (block->page.zip.data) { + ut_ad(!index->table->is_temporary()); + /* Reset the IBUF_BITMAP_FREE bits, because + page_cur_tuple_insert() will have attempted page + reorganize before failing. */ + if (leaf + && !dict_index_is_clust(index)) { + ibuf_reset_free_bits(block); + } + + goto fail; + } else { + ut_ad(!reorg); + + /* If the record did not fit, reorganize */ + if (!btr_page_reorganize(page_cursor, index, mtr)) { + ut_ad(0); + goto fail; + } + + ut_ad(page_get_max_insert_size(page, 1) == max_size); + + reorg = TRUE; + + *rec = page_cur_tuple_insert(page_cursor, entry, index, + offsets, heap, n_ext, mtr); + + if (UNIV_UNLIKELY(!*rec)) { + ib::fatal() << "Cannot insert tuple " << *entry + << "into index " << index->name + << " of table " << index->table->name + << ". Max size: " << max_size; + } + } + +#ifdef BTR_CUR_HASH_ADAPT + if (!leaf) { +# ifdef MYSQL_INDEX_DISABLE_AHI + } else if (index->disable_ahi) { +# endif + } else if (entry->info_bits & REC_INFO_MIN_REC_FLAG) { + ut_ad(entry->is_metadata()); + ut_ad(index->is_instant()); + ut_ad(flags == BTR_NO_LOCKING_FLAG); + } else { + rw_lock_t* ahi_latch = btr_search_sys.get_latch(*index); + if (!reorg && cursor->flag == BTR_CUR_HASH) { + btr_search_update_hash_node_on_insert( + cursor, ahi_latch); + } else { + btr_search_update_hash_on_insert(cursor, ahi_latch); + } + } +#endif /* BTR_CUR_HASH_ADAPT */ + + if (!(flags & BTR_NO_LOCKING_FLAG) && inherit) { + + lock_update_insert(block, *rec); + } + + if (leaf + && !dict_index_is_clust(index) + && !index->table->is_temporary()) { + /* Update the free bits of the B-tree page in the + insert buffer bitmap. */ + + /* The free bits in the insert buffer bitmap must + never exceed the free space on a page. It is safe to + decrement or reset the bits in the bitmap in a + mini-transaction that is committed before the + mini-transaction that affects the free space. */ + + /* It is unsafe to increment the bits in a separately + committed mini-transaction, because in crash recovery, + the free bits could momentarily be set too high. */ + + if (block->page.zip.data) { + /* Update the bits in the same mini-transaction. */ + ibuf_update_free_bits_zip(block, mtr); + } else { + /* Decrement the bits in a separate + mini-transaction. */ + ibuf_update_free_bits_if_full( + block, max_size, + rec_size + PAGE_DIR_SLOT_SIZE); + } + } + + *big_rec = big_rec_vec; + + return(DB_SUCCESS); +} + +/*************************************************************//** +Performs an insert on a page of an index tree. It is assumed that mtr +holds an x-latch on the tree and on the cursor page. If the insert is +made on the leaf level, to avoid deadlocks, mtr must also own x-latches +to brothers of page, if those brothers exist. +@return DB_SUCCESS or error number */ +dberr_t +btr_cur_pessimistic_insert( +/*=======================*/ + ulint flags, /*!< in: undo logging and locking flags: if not + zero, the parameter thr should be + specified; if no undo logging is specified, + then the caller must have reserved enough + free extents in the file space so that the + insertion will certainly succeed */ + btr_cur_t* cursor, /*!< in: cursor after which to insert; + cursor stays valid */ + rec_offs** offsets,/*!< out: offsets on *rec */ + mem_heap_t** heap, /*!< in/out: pointer to memory heap + that can be emptied */ + dtuple_t* entry, /*!< in/out: entry to insert */ + rec_t** rec, /*!< out: pointer to inserted record if + succeed */ + big_rec_t** big_rec,/*!< out: big rec vector whose fields have to + be stored externally by the caller */ + ulint n_ext, /*!< in: number of externally stored columns */ + que_thr_t* thr, /*!< in/out: query thread; can be NULL if + !(~flags + & (BTR_NO_LOCKING_FLAG + | BTR_NO_UNDO_LOG_FLAG)) */ + mtr_t* mtr) /*!< in/out: mini-transaction */ +{ + dict_index_t* index = cursor->index; + big_rec_t* big_rec_vec = NULL; + dberr_t err; + bool inherit = false; + bool success; + uint32_t n_reserved = 0; + + ut_ad(dtuple_check_typed(entry)); + ut_ad(thr || !(~flags & (BTR_NO_LOCKING_FLAG | BTR_NO_UNDO_LOG_FLAG))); + + *big_rec = NULL; + + ut_ad(mtr->memo_contains_flagged(&index->lock, MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(cursor), + MTR_MEMO_PAGE_X_FIX)); + ut_ad(!dict_index_is_online_ddl(index) + || dict_index_is_clust(index) + || (flags & BTR_CREATE_FLAG)); + + cursor->flag = BTR_CUR_BINARY; + + /* Check locks and write to undo log, if specified */ + + err = btr_cur_ins_lock_and_undo(flags, cursor, entry, + thr, mtr, &inherit); + + if (err != DB_SUCCESS) { + + return(err); + } + + if (!(flags & BTR_NO_UNDO_LOG_FLAG)) { + /* First reserve enough free space for the file segments + of the index tree, so that the insert will not fail because + of lack of space */ + + uint32_t n_extents = uint32_t(cursor->tree_height / 16 + 3); + + success = fsp_reserve_free_extents(&n_reserved, + index->table->space, + n_extents, FSP_NORMAL, mtr); + if (!success) { + return(DB_OUT_OF_FILE_SPACE); + } + } + + if (page_zip_rec_needs_ext(rec_get_converted_size(index, entry, n_ext), + index->table->not_redundant(), + dtuple_get_n_fields(entry), + btr_cur_get_block(cursor)->zip_size()) + || UNIV_UNLIKELY(entry->is_alter_metadata() + && !dfield_is_ext( + dtuple_get_nth_field( + entry, + index->first_user_field())))) { + /* The record is so big that we have to store some fields + externally on separate database pages */ + + if (UNIV_LIKELY_NULL(big_rec_vec)) { + /* This should never happen, but we handle + the situation in a robust manner. */ + ut_ad(0); + dtuple_convert_back_big_rec(index, entry, big_rec_vec); + } + + big_rec_vec = dtuple_convert_big_rec(index, 0, entry, &n_ext); + + if (big_rec_vec == NULL) { + + index->table->space->release_free_extents(n_reserved); + return(DB_TOO_BIG_RECORD); + } + } + + if (dict_index_get_page(index) + == btr_cur_get_block(cursor)->page.id().page_no()) { + + /* The page is the root page */ + *rec = btr_root_raise_and_insert( + flags, cursor, offsets, heap, entry, n_ext, mtr); + } else { + *rec = btr_page_split_and_insert( + flags, cursor, offsets, heap, entry, n_ext, mtr); + } + + if (*rec == NULL && os_has_said_disk_full) { + return(DB_OUT_OF_FILE_SPACE); + } + + ut_ad(page_rec_get_next(btr_cur_get_rec(cursor)) == *rec + || dict_index_is_spatial(index)); + + if (!(flags & BTR_NO_LOCKING_FLAG)) { + ut_ad(!index->table->is_temporary()); + if (dict_index_is_spatial(index)) { + /* Do nothing */ + } else { + /* The cursor might be moved to the other page + and the max trx id field should be updated after + the cursor was fixed. */ + if (!dict_index_is_clust(index)) { + page_update_max_trx_id( + btr_cur_get_block(cursor), + btr_cur_get_page_zip(cursor), + thr_get_trx(thr)->id, mtr); + } + + if (!page_rec_is_infimum(btr_cur_get_rec(cursor)) + || !page_has_prev(btr_cur_get_page(cursor))) { + /* split and inserted need to call + lock_update_insert() always. */ + inherit = true; + } + } + } + + if (!page_is_leaf(btr_cur_get_page(cursor))) { + ut_ad(!big_rec_vec); + } else { +#ifdef BTR_CUR_HASH_ADAPT +# ifdef MYSQL_INDEX_DISABLE_AHI + if (index->disable_ahi); else +# endif + if (entry->info_bits & REC_INFO_MIN_REC_FLAG) { + ut_ad(entry->is_metadata()); + ut_ad(index->is_instant()); + ut_ad(flags & BTR_NO_LOCKING_FLAG); + ut_ad(!(flags & BTR_CREATE_FLAG)); + } else { + btr_search_update_hash_on_insert( + cursor, btr_search_sys.get_latch(*index)); + } +#endif /* BTR_CUR_HASH_ADAPT */ + if (inherit && !(flags & BTR_NO_LOCKING_FLAG)) { + + lock_update_insert(btr_cur_get_block(cursor), *rec); + } + } + + index->table->space->release_free_extents(n_reserved); + *big_rec = big_rec_vec; + + return(DB_SUCCESS); +} + +/*==================== B-TREE UPDATE =========================*/ + +/*************************************************************//** +For an update, checks the locks and does the undo logging. +@return DB_SUCCESS, DB_WAIT_LOCK, or error number */ +UNIV_INLINE MY_ATTRIBUTE((warn_unused_result)) +dberr_t +btr_cur_upd_lock_and_undo( +/*======================*/ + ulint flags, /*!< in: undo logging and locking flags */ + btr_cur_t* cursor, /*!< in: cursor on record to update */ + const rec_offs* offsets,/*!< in: rec_get_offsets() on cursor */ + const upd_t* update, /*!< in: update vector */ + ulint cmpl_info,/*!< in: compiler info on secondary index + updates */ + que_thr_t* thr, /*!< in: query thread + (can be NULL if BTR_NO_LOCKING_FLAG) */ + mtr_t* mtr, /*!< in/out: mini-transaction */ + roll_ptr_t* roll_ptr)/*!< out: roll pointer */ +{ + dict_index_t* index; + const rec_t* rec; + dberr_t err; + + ut_ad((thr != NULL) || (flags & BTR_NO_LOCKING_FLAG)); + + rec = btr_cur_get_rec(cursor); + index = cursor->index; + + ut_ad(rec_offs_validate(rec, index, offsets)); + ut_ad(mtr->is_named_space(index->table->space)); + + if (!dict_index_is_clust(index)) { + ut_ad(dict_index_is_online_ddl(index) + == !!(flags & BTR_CREATE_FLAG)); + + /* We do undo logging only when we update a clustered index + record */ + return(lock_sec_rec_modify_check_and_lock( + flags, btr_cur_get_block(cursor), rec, + index, thr, mtr)); + } + + /* Check if we have to wait for a lock: enqueue an explicit lock + request if yes */ + + if (!(flags & BTR_NO_LOCKING_FLAG)) { + err = lock_clust_rec_modify_check_and_lock( + flags, btr_cur_get_block(cursor), rec, index, + offsets, thr); + if (err != DB_SUCCESS) { + return(err); + } + } + + /* Append the info about the update in the undo log */ + + return((flags & BTR_NO_UNDO_LOG_FLAG) + ? DB_SUCCESS + : trx_undo_report_row_operation( + thr, index, NULL, update, + cmpl_info, rec, offsets, roll_ptr)); +} + +/** Write DB_TRX_ID,DB_ROLL_PTR to a clustered index entry. +@param[in,out] entry clustered index entry +@param[in] index clustered index +@param[in] trx_id DB_TRX_ID +@param[in] roll_ptr DB_ROLL_PTR */ +static void btr_cur_write_sys( + dtuple_t* entry, + const dict_index_t* index, + trx_id_t trx_id, + roll_ptr_t roll_ptr) +{ + dfield_t* t = dtuple_get_nth_field(entry, index->db_trx_id()); + ut_ad(t->len == DATA_TRX_ID_LEN); + trx_write_trx_id(static_cast<byte*>(t->data), trx_id); + dfield_t* r = dtuple_get_nth_field(entry, index->db_roll_ptr()); + ut_ad(r->len == DATA_ROLL_PTR_LEN); + trx_write_roll_ptr(static_cast<byte*>(r->data), roll_ptr); +} + +/** Update DB_TRX_ID, DB_ROLL_PTR in a clustered index record. +@param[in,out] block clustered index leaf page +@param[in,out] rec clustered index record +@param[in] index clustered index +@param[in] offsets rec_get_offsets(rec, index) +@param[in] trx transaction +@param[in] roll_ptr DB_ROLL_PTR value +@param[in,out] mtr mini-transaction */ +static void btr_cur_upd_rec_sys(buf_block_t *block, rec_t *rec, + dict_index_t *index, const rec_offs *offsets, + const trx_t *trx, roll_ptr_t roll_ptr, + mtr_t *mtr) +{ + ut_ad(index->is_primary()); + ut_ad(rec_offs_validate(rec, index, offsets)); + + if (UNIV_LIKELY_NULL(block->page.zip.data)) + { + page_zip_write_trx_id_and_roll_ptr(block, rec, offsets, index->db_trx_id(), + trx->id, roll_ptr, mtr); + return; + } + + ulint offset= index->trx_id_offset; + + if (!offset) + offset= row_get_trx_id_offset(index, offsets); + + compile_time_assert(DATA_TRX_ID + 1 == DATA_ROLL_PTR); + + /* During IMPORT the trx id in the record can be in the future, if + the .ibd file is being imported from another instance. During IMPORT + roll_ptr will be 0. */ + ut_ad(roll_ptr == 0 || + lock_check_trx_id_sanity(trx_read_trx_id(rec + offset), + rec, index, offsets)); + + byte sys[DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN]; + + trx_write_trx_id(sys, trx->id); + trx_write_roll_ptr(sys + DATA_TRX_ID_LEN, roll_ptr); + + ulint d= 0; + const byte *src= nullptr; + byte *dest= rec + offset; + ulint len= DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN; + + if (UNIV_LIKELY(index->trx_id_offset)) + { + const rec_t *prev= page_rec_get_prev_const(rec); + if (UNIV_UNLIKELY(prev == rec)) + ut_ad(0); + else if (page_rec_is_infimum(prev)); + else + for (src= prev + offset; d < DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN; d++) + if (src[d] != sys[d]) + break; + if (d > 6 && memcmp(dest, sys, d)) + { + /* We save space by replacing a single record + + WRITE,page_offset(dest),byte[13] + + with two records: + + MEMMOVE,page_offset(dest),d(1 byte),offset(1..3 bytes), + WRITE|0x80,0,byte[13-d] + + The single WRITE record would be x+13 bytes long, with x>2. + The MEMMOVE record would be up to x+1+3 = x+4 bytes, and the + second WRITE would be 1+1+13-d = 15-d bytes. + + The total size is: x+13 versus x+4+15-d = x+19-d bytes. + To save space, we must have d>6, that is, the complete DB_TRX_ID and + the first byte(s) of DB_ROLL_PTR must match the previous record. */ + memcpy(dest, src, d); + mtr->memmove(*block, page_offset(dest), page_offset(src), d); + dest+= d; + len-= d; + /* DB_TRX_ID,DB_ROLL_PTR must be unique in each record when + DB_TRX_ID refers to an active transaction. */ + ut_ad(len); + } + else + d= 0; + } + + if (UNIV_LIKELY(len)) /* extra safety, to avoid corrupting the log */ + mtr->memcpy<mtr_t::MAYBE_NOP>(*block, dest, sys + d, len); +} + +/*************************************************************//** +See if there is enough place in the page modification log to log +an update-in-place. + +@retval false if out of space; IBUF_BITMAP_FREE will be reset +outside mtr if the page was recompressed +@retval true if enough place; + +IMPORTANT: The caller will have to update IBUF_BITMAP_FREE if this is +a secondary index leaf page. This has to be done either within the +same mini-transaction, or by invoking ibuf_reset_free_bits() before +mtr_commit(mtr). */ +bool +btr_cur_update_alloc_zip_func( +/*==========================*/ + page_zip_des_t* page_zip,/*!< in/out: compressed page */ + page_cur_t* cursor, /*!< in/out: B-tree page cursor */ + dict_index_t* index, /*!< in: the index corresponding to cursor */ +#ifdef UNIV_DEBUG + rec_offs* offsets,/*!< in/out: offsets of the cursor record */ +#endif /* UNIV_DEBUG */ + ulint length, /*!< in: size needed */ + bool create, /*!< in: true=delete-and-insert, + false=update-in-place */ + mtr_t* mtr) /*!< in/out: mini-transaction */ +{ + + /* Have a local copy of the variables as these can change + dynamically. */ + const page_t* page = page_cur_get_page(cursor); + + ut_ad(page_zip == page_cur_get_page_zip(cursor)); + ut_ad(!dict_index_is_ibuf(index)); + ut_ad(rec_offs_validate(page_cur_get_rec(cursor), index, offsets)); + + if (page_zip_available(page_zip, dict_index_is_clust(index), + length, create)) { + return(true); + } + + if (!page_zip->m_nonempty && !page_has_garbage(page)) { + /* The page has been freshly compressed, so + reorganizing it will not help. */ + return(false); + } + + if (create && page_is_leaf(page) + && (length + page_get_data_size(page) + >= dict_index_zip_pad_optimal_page_size(index))) { + return(false); + } + + if (!btr_page_reorganize(cursor, index, mtr)) { + goto out_of_space; + } + + rec_offs_make_valid(page_cur_get_rec(cursor), index, + page_is_leaf(page), offsets); + + /* After recompressing a page, we must make sure that the free + bits in the insert buffer bitmap will not exceed the free + space on the page. Because this function will not attempt + recompression unless page_zip_available() fails above, it is + safe to reset the free bits if page_zip_available() fails + again, below. The free bits can safely be reset in a separate + mini-transaction. If page_zip_available() succeeds below, we + can be sure that the btr_page_reorganize() above did not reduce + the free space available on the page. */ + + if (page_zip_available(page_zip, dict_index_is_clust(index), + length, create)) { + return(true); + } + +out_of_space: + ut_ad(rec_offs_validate(page_cur_get_rec(cursor), index, offsets)); + + /* Out of space: reset the free bits. */ + if (!dict_index_is_clust(index) + && !index->table->is_temporary() + && page_is_leaf(page)) { + ibuf_reset_free_bits(page_cur_get_block(cursor)); + } + + return(false); +} + +/** Apply an update vector to a record. No field size changes are allowed. + +This is usually invoked on a clustered index. The only use case for a +secondary index is row_ins_sec_index_entry_by_modify() or its +counterpart in ibuf_insert_to_index_page(). +@param[in,out] rec index record +@param[in] index the index of the record +@param[in] offsets rec_get_offsets(rec, index) +@param[in] update update vector +@param[in,out] block index page +@param[in,out] mtr mini-transaction */ +void btr_cur_upd_rec_in_place(rec_t *rec, const dict_index_t *index, + const rec_offs *offsets, const upd_t *update, + buf_block_t *block, mtr_t *mtr) +{ + ut_ad(rec_offs_validate(rec, index, offsets)); + ut_ad(!index->table->skip_alter_undo); + ut_ad(!block->page.zip.data || index->table->not_redundant()); + +#ifdef UNIV_DEBUG + if (rec_offs_comp(offsets)) { + switch (rec_get_status(rec)) { + case REC_STATUS_ORDINARY: + break; + case REC_STATUS_INSTANT: + ut_ad(index->is_instant()); + break; + case REC_STATUS_NODE_PTR: + case REC_STATUS_INFIMUM: + case REC_STATUS_SUPREMUM: + ut_ad("wrong record status in update" == 0); + } + } +#endif /* UNIV_DEBUG */ + + static_assert(REC_INFO_BITS_SHIFT == 0, "compatibility"); + if (UNIV_LIKELY_NULL(block->page.zip.data)) { + ut_ad(rec_offs_comp(offsets)); + byte* info_bits = &rec[-REC_NEW_INFO_BITS]; + const bool flip_del_mark = (*info_bits ^ update->info_bits) + & REC_INFO_DELETED_FLAG; + *info_bits &= byte(~REC_INFO_BITS_MASK); + *info_bits |= update->info_bits; + + if (flip_del_mark) { + page_zip_rec_set_deleted(block, rec, update->info_bits + & REC_INFO_DELETED_FLAG, mtr); + } + } else { + byte* info_bits = &rec[rec_offs_comp(offsets) + ? -REC_NEW_INFO_BITS + : -REC_OLD_INFO_BITS]; + + mtr->write<1,mtr_t::MAYBE_NOP>(*block, info_bits, + (*info_bits + & ~REC_INFO_BITS_MASK) + | update->info_bits); + } + + for (ulint i = 0; i < update->n_fields; i++) { + const upd_field_t* uf = upd_get_nth_field(update, i); + if (upd_fld_is_virtual_col(uf) && !index->has_virtual()) { + continue; + } + const ulint n = uf->field_no; + + ut_ad(!dfield_is_ext(&uf->new_val) + == !rec_offs_nth_extern(offsets, n)); + ut_ad(!rec_offs_nth_default(offsets, n)); + + if (UNIV_UNLIKELY(dfield_is_null(&uf->new_val))) { + if (rec_offs_nth_sql_null(offsets, n)) { + ut_ad(index->table->is_instant()); + ut_ad(n >= index->n_core_fields); + continue; + } + + ut_ad(!index->table->not_redundant()); + switch (ulint size = rec_get_nth_field_size(rec, n)) { + case 0: + break; + case 1: + mtr->write<1,mtr_t::MAYBE_NOP>( + *block, + rec_get_field_start_offs(rec, n) + rec, + 0U); + break; + default: + mtr->memset( + block, + page_offset(rec_get_field_start_offs( + rec, n) + rec), + size, 0); + } + ulint l = rec_get_1byte_offs_flag(rec) + ? (n + 1) : (n + 1) * 2; + byte* b = rec - REC_N_OLD_EXTRA_BYTES - l; + compile_time_assert(REC_1BYTE_SQL_NULL_MASK << 8 + == REC_2BYTE_SQL_NULL_MASK); + mtr->write<1>(*block, b, + byte(*b | REC_1BYTE_SQL_NULL_MASK)); + continue; + } + + ulint len; + byte* data = rec_get_nth_field(rec, offsets, n, &len); + if (UNIV_LIKELY_NULL(block->page.zip.data)) { + ut_ad(len == uf->new_val.len); + memcpy(data, uf->new_val.data, len); + continue; + } + + if (UNIV_UNLIKELY(len != uf->new_val.len)) { + ut_ad(len == UNIV_SQL_NULL); + ut_ad(!rec_offs_comp(offsets)); + len = uf->new_val.len; + ut_ad(len == rec_get_nth_field_size(rec, n)); + ulint l = rec_get_1byte_offs_flag(rec) + ? (n + 1) : (n + 1) * 2; + byte* b = rec - REC_N_OLD_EXTRA_BYTES - l; + compile_time_assert(REC_1BYTE_SQL_NULL_MASK << 8 + == REC_2BYTE_SQL_NULL_MASK); + mtr->write<1>(*block, b, + byte(*b & ~REC_1BYTE_SQL_NULL_MASK)); + } + + if (len) { + mtr->memcpy<mtr_t::MAYBE_NOP>(*block, data, + uf->new_val.data, len); + } + } + + if (UNIV_LIKELY_NULL(block->page.zip.data)) { + page_zip_write_rec(block, rec, index, offsets, 0, mtr); + } +} + +/*************************************************************//** +Updates a record when the update causes no size changes in its fields. +We assume here that the ordering fields of the record do not change. +@return locking or undo log related error code, or +@retval DB_SUCCESS on success +@retval DB_ZIP_OVERFLOW if there is not enough space left +on the compressed page (IBUF_BITMAP_FREE was reset outside mtr) */ +dberr_t +btr_cur_update_in_place( +/*====================*/ + ulint flags, /*!< in: undo logging and locking flags */ + btr_cur_t* cursor, /*!< in: cursor on the record to update; + cursor stays valid and positioned on the + same record */ + rec_offs* offsets,/*!< in/out: offsets on cursor->page_cur.rec */ + const upd_t* update, /*!< in: update vector */ + ulint cmpl_info,/*!< in: compiler info on secondary index + updates */ + que_thr_t* thr, /*!< in: query thread */ + trx_id_t trx_id, /*!< in: transaction id */ + mtr_t* mtr) /*!< in/out: mini-transaction; if this + is a secondary index, the caller must + mtr_commit(mtr) before latching any + further pages */ +{ + dict_index_t* index; + dberr_t err; + rec_t* rec; + roll_ptr_t roll_ptr = 0; + ulint was_delete_marked; + + ut_ad(page_is_leaf(cursor->page_cur.block->frame)); + rec = btr_cur_get_rec(cursor); + index = cursor->index; + ut_ad(rec_offs_validate(rec, index, offsets)); + ut_ad(!!page_rec_is_comp(rec) == dict_table_is_comp(index->table)); + ut_ad(trx_id > 0 || (flags & BTR_KEEP_SYS_FLAG) + || index->table->is_temporary()); + /* The insert buffer tree should never be updated in place. */ + ut_ad(!dict_index_is_ibuf(index)); + ut_ad(dict_index_is_online_ddl(index) == !!(flags & BTR_CREATE_FLAG) + || dict_index_is_clust(index)); + ut_ad(thr_get_trx(thr)->id == trx_id + || (flags & ulint(~(BTR_KEEP_POS_FLAG | BTR_KEEP_IBUF_BITMAP))) + == (BTR_NO_UNDO_LOG_FLAG | BTR_NO_LOCKING_FLAG + | BTR_CREATE_FLAG | BTR_KEEP_SYS_FLAG)); + ut_ad(fil_page_index_page_check(btr_cur_get_page(cursor))); + ut_ad(btr_page_get_index_id(btr_cur_get_page(cursor)) == index->id); + ut_ad(!(update->info_bits & REC_INFO_MIN_REC_FLAG)); + + DBUG_LOG("ib_cur", + "update-in-place " << index->name << " (" << index->id + << ") by " << ib::hex(trx_id) << ": " + << rec_printer(rec, offsets).str()); + + buf_block_t* block = btr_cur_get_block(cursor); + page_zip_des_t* page_zip = buf_block_get_page_zip(block); + + /* Check that enough space is available on the compressed page. */ + if (UNIV_LIKELY_NULL(page_zip)) { + ut_ad(!index->table->is_temporary()); + + if (!btr_cur_update_alloc_zip( + page_zip, btr_cur_get_page_cur(cursor), + index, offsets, rec_offs_size(offsets), + false, mtr)) { + return(DB_ZIP_OVERFLOW); + } + + rec = btr_cur_get_rec(cursor); + } + + /* Do lock checking and undo logging */ + err = btr_cur_upd_lock_and_undo(flags, cursor, offsets, + update, cmpl_info, + thr, mtr, &roll_ptr); + if (UNIV_UNLIKELY(err != DB_SUCCESS)) { + /* We may need to update the IBUF_BITMAP_FREE + bits after a reorganize that was done in + btr_cur_update_alloc_zip(). */ + goto func_exit; + } + + if (!(flags & BTR_KEEP_SYS_FLAG)) { + btr_cur_upd_rec_sys(block, rec, index, offsets, + thr_get_trx(thr), roll_ptr, mtr); + } + + was_delete_marked = rec_get_deleted_flag( + rec, page_is_comp(buf_block_get_frame(block))); + /* In delete-marked records, DB_TRX_ID must always refer to an + existing undo log record. */ + ut_ad(!was_delete_marked + || !dict_index_is_clust(index) + || row_get_rec_trx_id(rec, index, offsets)); + +#ifdef BTR_CUR_HASH_ADAPT + { + rw_lock_t* ahi_latch = block->index + ? btr_search_sys.get_latch(*index) : NULL; + if (ahi_latch) { + /* TO DO: Can we skip this if none of the fields + index->search_info->curr_n_fields + are being updated? */ + + /* The function row_upd_changes_ord_field_binary + does not work on a secondary index. */ + + if (!dict_index_is_clust(index) + || row_upd_changes_ord_field_binary( + index, update, thr, NULL, NULL)) { + ut_ad(!(update->info_bits + & REC_INFO_MIN_REC_FLAG)); + /* Remove possible hash index pointer + to this record */ + btr_search_update_hash_on_delete(cursor); + } + + rw_lock_x_lock(ahi_latch); + } + + assert_block_ahi_valid(block); +#endif /* BTR_CUR_HASH_ADAPT */ + + btr_cur_upd_rec_in_place(rec, index, offsets, update, block, + mtr); + +#ifdef BTR_CUR_HASH_ADAPT + if (ahi_latch) { + rw_lock_x_unlock(ahi_latch); + } + } +#endif /* BTR_CUR_HASH_ADAPT */ + + if (was_delete_marked + && !rec_get_deleted_flag( + rec, page_is_comp(buf_block_get_frame(block)))) { + /* The new updated record owns its possible externally + stored fields */ + + btr_cur_unmark_extern_fields(block, rec, index, offsets, mtr); + } + + ut_ad(err == DB_SUCCESS); + +func_exit: + if (page_zip + && !(flags & BTR_KEEP_IBUF_BITMAP) + && !dict_index_is_clust(index) + && page_is_leaf(buf_block_get_frame(block))) { + /* Update the free bits in the insert buffer. */ + ut_ad(!index->table->is_temporary()); + ibuf_update_free_bits_zip(block, mtr); + } + + return(err); +} + +/** Trim a metadata record during the rollback of instant ALTER TABLE. +@param[in] entry metadata tuple +@param[in] index primary key +@param[in] update update vector for the rollback */ +ATTRIBUTE_COLD +static void btr_cur_trim_alter_metadata(dtuple_t* entry, + const dict_index_t* index, + const upd_t* update) +{ + ut_ad(index->is_instant()); + ut_ad(update->is_alter_metadata()); + ut_ad(entry->is_alter_metadata()); + + ut_ad(update->fields[0].field_no == index->first_user_field()); + ut_ad(update->fields[0].new_val.ext); + ut_ad(update->fields[0].new_val.len == FIELD_REF_SIZE); + ut_ad(entry->n_fields - 1 == index->n_fields); + + const byte* ptr = static_cast<const byte*>( + update->fields[0].new_val.data); + ut_ad(!mach_read_from_4(ptr + BTR_EXTERN_LEN)); + ut_ad(mach_read_from_4(ptr + BTR_EXTERN_LEN + 4) > 4); + ut_ad(mach_read_from_4(ptr + BTR_EXTERN_OFFSET) == FIL_PAGE_DATA); + ut_ad(mach_read_from_4(ptr + BTR_EXTERN_SPACE_ID) + == index->table->space->id); + + ulint n_fields = update->fields[1].field_no; + ut_ad(n_fields <= index->n_fields); + if (n_fields != index->n_uniq) { + ut_ad(n_fields + >= index->n_core_fields); + entry->n_fields = n_fields; + return; + } + + /* This is based on dict_table_t::deserialise_columns() + and btr_cur_instant_init_low(). */ + mtr_t mtr; + mtr.start(); + buf_block_t* block = buf_page_get( + page_id_t(index->table->space->id, + mach_read_from_4(ptr + BTR_EXTERN_PAGE_NO)), + 0, RW_S_LATCH, &mtr); + buf_block_dbg_add_level(block, SYNC_EXTERN_STORAGE); + ut_ad(fil_page_get_type(block->frame) == FIL_PAGE_TYPE_BLOB); + ut_ad(mach_read_from_4(&block->frame[FIL_PAGE_DATA + + BTR_BLOB_HDR_NEXT_PAGE_NO]) + == FIL_NULL); + ut_ad(mach_read_from_4(&block->frame[FIL_PAGE_DATA + + BTR_BLOB_HDR_PART_LEN]) + == mach_read_from_4(ptr + BTR_EXTERN_LEN + 4)); + n_fields = mach_read_from_4( + &block->frame[FIL_PAGE_DATA + BTR_BLOB_HDR_SIZE]) + + index->first_user_field(); + /* Rollback should not increase the number of fields. */ + ut_ad(n_fields <= index->n_fields); + ut_ad(n_fields + 1 <= entry->n_fields); + /* dict_index_t::clear_instant_alter() cannot be invoked while + rollback of an instant ALTER TABLE transaction is in progress + for an is_alter_metadata() record. */ + ut_ad(n_fields >= index->n_core_fields); + + mtr.commit(); + entry->n_fields = n_fields + 1; +} + +/** Trim an update tuple due to instant ADD COLUMN, if needed. +For normal records, the trailing instantly added fields that match +the initial default values are omitted. + +For the special metadata record on a table on which instant +ADD COLUMN has already been executed, both ADD COLUMN and the +rollback of ADD COLUMN need to be handled specially. + +@param[in,out] entry index entry +@param[in] index index +@param[in] update update vector +@param[in] thr execution thread */ +static inline +void +btr_cur_trim( + dtuple_t* entry, + const dict_index_t* index, + const upd_t* update, + const que_thr_t* thr) +{ + if (!index->is_instant()) { + } else if (UNIV_UNLIKELY(update->is_metadata())) { + /* We are either updating a metadata record + (instant ALTER TABLE on a table where instant ALTER was + already executed) or rolling back such an operation. */ + ut_ad(!upd_get_nth_field(update, 0)->orig_len); + ut_ad(entry->is_metadata()); + + if (thr->graph->trx->in_rollback) { + /* This rollback can occur either as part of + ha_innobase::commit_inplace_alter_table() rolling + back after a failed innobase_add_instant_try(), + or as part of crash recovery. Either way, the + table will be in the data dictionary cache, with + the instantly added columns going to be removed + later in the rollback. */ + ut_ad(index->table->cached); + /* The DB_TRX_ID,DB_ROLL_PTR are always last, + and there should be some change to roll back. + The first field in the update vector is the + first instantly added column logged by + innobase_add_instant_try(). */ + ut_ad(update->n_fields > 2); + if (update->is_alter_metadata()) { + btr_cur_trim_alter_metadata( + entry, index, update); + return; + } + ut_ad(!entry->is_alter_metadata()); + + ulint n_fields = upd_get_nth_field(update, 0) + ->field_no; + ut_ad(n_fields + 1 >= entry->n_fields); + entry->n_fields = n_fields; + } + } else { + entry->trim(*index); + } +} + +/*************************************************************//** +Tries to update a record on a page in an index tree. It is assumed that mtr +holds an x-latch on the page. The operation does not succeed if there is too +little space on the page or if the update would result in too empty a page, +so that tree compression is recommended. We assume here that the ordering +fields of the record do not change. +@return error code, including +@retval DB_SUCCESS on success +@retval DB_OVERFLOW if the updated record does not fit +@retval DB_UNDERFLOW if the page would become too empty +@retval DB_ZIP_OVERFLOW if there is not enough space left +on the compressed page (IBUF_BITMAP_FREE was reset outside mtr) */ +dberr_t +btr_cur_optimistic_update( +/*======================*/ + ulint flags, /*!< in: undo logging and locking flags */ + btr_cur_t* cursor, /*!< in: cursor on the record to update; + cursor stays valid and positioned on the + same record */ + rec_offs** offsets,/*!< out: offsets on cursor->page_cur.rec */ + mem_heap_t** heap, /*!< in/out: pointer to NULL or memory heap */ + const upd_t* update, /*!< in: update vector; this must also + contain trx id and roll ptr fields */ + ulint cmpl_info,/*!< in: compiler info on secondary index + updates */ + que_thr_t* thr, /*!< in: query thread */ + trx_id_t trx_id, /*!< in: transaction id */ + mtr_t* mtr) /*!< in/out: mini-transaction; if this + is a secondary index, the caller must + mtr_commit(mtr) before latching any + further pages */ +{ + dict_index_t* index; + page_cur_t* page_cursor; + dberr_t err; + buf_block_t* block; + page_t* page; + page_zip_des_t* page_zip; + rec_t* rec; + ulint max_size; + ulint new_rec_size; + ulint old_rec_size; + ulint max_ins_size = 0; + dtuple_t* new_entry; + roll_ptr_t roll_ptr; + ulint i; + + block = btr_cur_get_block(cursor); + page = buf_block_get_frame(block); + rec = btr_cur_get_rec(cursor); + index = cursor->index; + ut_ad(trx_id > 0 || (flags & BTR_KEEP_SYS_FLAG) + || index->table->is_temporary()); + ut_ad(!!page_rec_is_comp(rec) == dict_table_is_comp(index->table)); + ut_ad(mtr->memo_contains_flagged(block, MTR_MEMO_PAGE_X_FIX)); + /* This is intended only for leaf page updates */ + ut_ad(page_is_leaf(page)); + /* The insert buffer tree should never be updated in place. */ + ut_ad(!dict_index_is_ibuf(index)); + ut_ad(dict_index_is_online_ddl(index) == !!(flags & BTR_CREATE_FLAG) + || dict_index_is_clust(index)); + ut_ad(thr_get_trx(thr)->id == trx_id + || (flags & ulint(~(BTR_KEEP_POS_FLAG | BTR_KEEP_IBUF_BITMAP))) + == (BTR_NO_UNDO_LOG_FLAG | BTR_NO_LOCKING_FLAG + | BTR_CREATE_FLAG | BTR_KEEP_SYS_FLAG)); + ut_ad(fil_page_index_page_check(page)); + ut_ad(btr_page_get_index_id(page) == index->id); + + *offsets = rec_get_offsets(rec, index, *offsets, index->n_core_fields, + ULINT_UNDEFINED, heap); +#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG + ut_a(!rec_offs_any_null_extern(rec, *offsets) + || thr_get_trx(thr) == trx_roll_crash_recv_trx); +#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */ + + if (UNIV_LIKELY(!update->is_metadata()) + && !row_upd_changes_field_size_or_external(index, *offsets, + update)) { + + /* The simplest and the most common case: the update does not + change the size of any field and none of the updated fields is + externally stored in rec or update, and there is enough space + on the compressed page to log the update. */ + + return(btr_cur_update_in_place( + flags, cursor, *offsets, update, + cmpl_info, thr, trx_id, mtr)); + } + + if (rec_offs_any_extern(*offsets)) { +any_extern: + ut_ad(!index->is_ibuf()); + /* Externally stored fields are treated in pessimistic + update */ + + /* prefetch siblings of the leaf for the pessimistic + operation. */ + btr_cur_prefetch_siblings(block, index); + + return(DB_OVERFLOW); + } + + if (rec_is_metadata(rec, *index) && index->table->instant) { + goto any_extern; + } + + for (i = 0; i < upd_get_n_fields(update); i++) { + if (dfield_is_ext(&upd_get_nth_field(update, i)->new_val)) { + + goto any_extern; + } + } + + DBUG_LOG("ib_cur", + "update " << index->name << " (" << index->id << ") by " + << ib::hex(trx_id) << ": " + << rec_printer(rec, *offsets).str()); + + page_cursor = btr_cur_get_page_cur(cursor); + + if (!*heap) { + *heap = mem_heap_create( + rec_offs_size(*offsets) + + DTUPLE_EST_ALLOC(rec_offs_n_fields(*offsets))); + } + + new_entry = row_rec_to_index_entry(rec, index, *offsets, *heap); + ut_ad(!dtuple_get_n_ext(new_entry)); + + /* The page containing the clustered index record + corresponding to new_entry is latched in mtr. + Thus the following call is safe. */ + row_upd_index_replace_new_col_vals_index_pos(new_entry, index, update, + *heap); + btr_cur_trim(new_entry, index, update, thr); + old_rec_size = rec_offs_size(*offsets); + new_rec_size = rec_get_converted_size(index, new_entry, 0); + + page_zip = buf_block_get_page_zip(block); +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip || page_zip_validate(page_zip, page, index)); +#endif /* UNIV_ZIP_DEBUG */ + + if (page_zip) { + ut_ad(!index->table->is_temporary()); + + if (page_zip_rec_needs_ext(new_rec_size, page_is_comp(page), + dict_index_get_n_fields(index), + block->zip_size())) { + goto any_extern; + } + + if (!btr_cur_update_alloc_zip( + page_zip, page_cursor, index, *offsets, + new_rec_size, true, mtr)) { + return(DB_ZIP_OVERFLOW); + } + + rec = page_cur_get_rec(page_cursor); + } + + /* We limit max record size to 16k even for 64k page size. */ + if (new_rec_size >= COMPRESSED_REC_MAX_DATA_SIZE || + (!dict_table_is_comp(index->table) + && new_rec_size >= REDUNDANT_REC_MAX_DATA_SIZE)) { + err = DB_OVERFLOW; + + goto func_exit; + } + + if (UNIV_UNLIKELY(new_rec_size + >= (page_get_free_space_of_empty(page_is_comp(page)) + / 2))) { + /* We may need to update the IBUF_BITMAP_FREE + bits after a reorganize that was done in + btr_cur_update_alloc_zip(). */ + err = DB_OVERFLOW; + goto func_exit; + } + + if (UNIV_UNLIKELY(page_get_data_size(page) + - old_rec_size + new_rec_size + < BTR_CUR_PAGE_COMPRESS_LIMIT(index))) { + /* We may need to update the IBUF_BITMAP_FREE + bits after a reorganize that was done in + btr_cur_update_alloc_zip(). */ + + /* The page would become too empty */ + err = DB_UNDERFLOW; + goto func_exit; + } + + /* We do not attempt to reorganize if the page is compressed. + This is because the page may fail to compress after reorganization. */ + max_size = page_zip + ? page_get_max_insert_size(page, 1) + : (old_rec_size + + page_get_max_insert_size_after_reorganize(page, 1)); + + if (!page_zip) { + max_ins_size = page_get_max_insert_size_after_reorganize( + page, 1); + } + + if (!(((max_size >= BTR_CUR_PAGE_REORGANIZE_LIMIT) + && (max_size >= new_rec_size)) + || (page_get_n_recs(page) <= 1))) { + + /* We may need to update the IBUF_BITMAP_FREE + bits after a reorganize that was done in + btr_cur_update_alloc_zip(). */ + + /* There was not enough space, or it did not pay to + reorganize: for simplicity, we decide what to do assuming a + reorganization is needed, though it might not be necessary */ + + err = DB_OVERFLOW; + goto func_exit; + } + + /* Do lock checking and undo logging */ + err = btr_cur_upd_lock_and_undo(flags, cursor, *offsets, + update, cmpl_info, + thr, mtr, &roll_ptr); + if (err != DB_SUCCESS) { + /* We may need to update the IBUF_BITMAP_FREE + bits after a reorganize that was done in + btr_cur_update_alloc_zip(). */ + goto func_exit; + } + + /* Ok, we may do the replacement. Store on the page infimum the + explicit locks on rec, before deleting rec (see the comment in + btr_cur_pessimistic_update). */ + if (!dict_table_is_locking_disabled(index->table)) { + lock_rec_store_on_page_infimum(block, rec); + } + + if (UNIV_UNLIKELY(update->is_metadata())) { + ut_ad(new_entry->is_metadata()); + ut_ad(index->is_instant()); + /* This can be innobase_add_instant_try() performing a + subsequent instant ADD COLUMN, or its rollback by + row_undo_mod_clust_low(). */ + ut_ad(flags & BTR_NO_LOCKING_FLAG); + } else { + btr_search_update_hash_on_delete(cursor); + } + + page_cur_delete_rec(page_cursor, index, *offsets, mtr); + + page_cur_move_to_prev(page_cursor); + + if (!(flags & BTR_KEEP_SYS_FLAG)) { + btr_cur_write_sys(new_entry, index, trx_id, roll_ptr); + } + + /* There are no externally stored columns in new_entry */ + rec = btr_cur_insert_if_possible( + cursor, new_entry, offsets, heap, 0/*n_ext*/, mtr); + ut_a(rec); /* <- We calculated above the insert would fit */ + + if (UNIV_UNLIKELY(update->is_metadata())) { + /* We must empty the PAGE_FREE list, because if this + was a rollback, the shortened metadata record + would have too many fields, and we would be unable to + know the size of the freed record. */ + btr_page_reorganize(page_cursor, index, mtr); + } else if (!dict_table_is_locking_disabled(index->table)) { + /* Restore the old explicit lock state on the record */ + lock_rec_restore_from_page_infimum(block, rec, block); + } + + page_cur_move_to_next(page_cursor); + ut_ad(err == DB_SUCCESS); + +func_exit: + if (!(flags & BTR_KEEP_IBUF_BITMAP) + && !dict_index_is_clust(index)) { + /* Update the free bits in the insert buffer. */ + if (page_zip) { + ut_ad(!index->table->is_temporary()); + ibuf_update_free_bits_zip(block, mtr); + } else if (!index->table->is_temporary()) { + ibuf_update_free_bits_low(block, max_ins_size, mtr); + } + } + + if (err != DB_SUCCESS) { + /* prefetch siblings of the leaf for the pessimistic + operation. */ + btr_cur_prefetch_siblings(block, index); + } + + return(err); +} + +/*************************************************************//** +If, in a split, a new supremum record was created as the predecessor of the +updated record, the supremum record must inherit exactly the locks on the +updated record. In the split it may have inherited locks from the successor +of the updated record, which is not correct. This function restores the +right locks for the new supremum. */ +static +void +btr_cur_pess_upd_restore_supremum( +/*==============================*/ + buf_block_t* block, /*!< in: buffer block of rec */ + const rec_t* rec, /*!< in: updated record */ + mtr_t* mtr) /*!< in: mtr */ +{ + page_t* page; + buf_block_t* prev_block; + + page = buf_block_get_frame(block); + + if (page_rec_get_next(page_get_infimum_rec(page)) != rec) { + /* Updated record is not the first user record on its page */ + + return; + } + + const uint32_t prev_page_no = btr_page_get_prev(page); + + const page_id_t page_id(block->page.id().space(), prev_page_no); + + ut_ad(prev_page_no != FIL_NULL); + prev_block = buf_page_get_with_no_latch(page_id, block->zip_size(), + mtr); +#ifdef UNIV_BTR_DEBUG + ut_a(btr_page_get_next(prev_block->frame) + == block->page.id().page_no()); +#endif /* UNIV_BTR_DEBUG */ + + /* We must already have an x-latch on prev_block! */ + ut_ad(mtr->memo_contains_flagged(prev_block, MTR_MEMO_PAGE_X_FIX)); + + lock_rec_reset_and_inherit_gap_locks(prev_block, block, + PAGE_HEAP_NO_SUPREMUM, + page_rec_get_heap_no(rec)); +} + +/*************************************************************//** +Performs an update of a record on a page of a tree. It is assumed +that mtr holds an x-latch on the tree and on the cursor page. If the +update is made on the leaf level, to avoid deadlocks, mtr must also +own x-latches to brothers of page, if those brothers exist. We assume +here that the ordering fields of the record do not change. +@return DB_SUCCESS or error code */ +dberr_t +btr_cur_pessimistic_update( +/*=======================*/ + ulint flags, /*!< in: undo logging, locking, and rollback + flags */ + btr_cur_t* cursor, /*!< in/out: cursor on the record to update; + cursor may become invalid if *big_rec == NULL + || !(flags & BTR_KEEP_POS_FLAG) */ + rec_offs** offsets,/*!< out: offsets on cursor->page_cur.rec */ + mem_heap_t** offsets_heap, + /*!< in/out: pointer to memory heap + that can be emptied */ + mem_heap_t* entry_heap, + /*!< in/out: memory heap for allocating + big_rec and the index tuple */ + big_rec_t** big_rec,/*!< out: big rec vector whose fields have to + be stored externally by the caller */ + upd_t* update, /*!< in/out: update vector; this is allowed to + also contain trx id and roll ptr fields. + Non-updated columns that are moved offpage will + be appended to this. */ + ulint cmpl_info,/*!< in: compiler info on secondary index + updates */ + que_thr_t* thr, /*!< in: query thread */ + trx_id_t trx_id, /*!< in: transaction id */ + mtr_t* mtr) /*!< in/out: mini-transaction; must be + committed before latching any further pages */ +{ + big_rec_t* big_rec_vec = NULL; + big_rec_t* dummy_big_rec; + dict_index_t* index; + buf_block_t* block; + page_zip_des_t* page_zip; + rec_t* rec; + page_cur_t* page_cursor; + dberr_t err; + dberr_t optim_err; + roll_ptr_t roll_ptr; + bool was_first; + uint32_t n_reserved = 0; + + *offsets = NULL; + *big_rec = NULL; + + block = btr_cur_get_block(cursor); + page_zip = buf_block_get_page_zip(block); + index = cursor->index; + + ut_ad(mtr->memo_contains_flagged(&index->lock, MTR_MEMO_X_LOCK | + MTR_MEMO_SX_LOCK)); + ut_ad(mtr->memo_contains_flagged(block, MTR_MEMO_PAGE_X_FIX)); +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip || page_zip_validate(page_zip, block->frame, index)); +#endif /* UNIV_ZIP_DEBUG */ + ut_ad(!page_zip || !index->table->is_temporary()); + /* The insert buffer tree should never be updated in place. */ + ut_ad(!dict_index_is_ibuf(index)); + ut_ad(trx_id > 0 || (flags & BTR_KEEP_SYS_FLAG) + || index->table->is_temporary()); + ut_ad(dict_index_is_online_ddl(index) == !!(flags & BTR_CREATE_FLAG) + || dict_index_is_clust(index)); + ut_ad(thr_get_trx(thr)->id == trx_id + || (flags & ulint(~BTR_KEEP_POS_FLAG)) + == (BTR_NO_UNDO_LOG_FLAG | BTR_NO_LOCKING_FLAG + | BTR_CREATE_FLAG | BTR_KEEP_SYS_FLAG)); + + err = optim_err = btr_cur_optimistic_update( + flags | BTR_KEEP_IBUF_BITMAP, + cursor, offsets, offsets_heap, update, + cmpl_info, thr, trx_id, mtr); + + switch (err) { + case DB_ZIP_OVERFLOW: + case DB_UNDERFLOW: + case DB_OVERFLOW: + break; + default: + err_exit: + /* We suppressed this with BTR_KEEP_IBUF_BITMAP. + For DB_ZIP_OVERFLOW, the IBUF_BITMAP_FREE bits were + already reset by btr_cur_update_alloc_zip() if the + page was recompressed. */ + if (page_zip + && optim_err != DB_ZIP_OVERFLOW + && !dict_index_is_clust(index) + && page_is_leaf(block->frame)) { + ut_ad(!index->table->is_temporary()); + ibuf_update_free_bits_zip(block, mtr); + } + + if (big_rec_vec != NULL) { + dtuple_big_rec_free(big_rec_vec); + } + + return(err); + } + + rec = btr_cur_get_rec(cursor); + ut_ad(rec_offs_validate(rec, index, *offsets)); + + dtuple_t* new_entry; + + const bool is_metadata = rec_is_metadata(rec, *index); + + if (UNIV_UNLIKELY(is_metadata)) { + ut_ad(update->is_metadata()); + ut_ad(flags & BTR_NO_LOCKING_FLAG); + ut_ad(index->is_instant()); + new_entry = row_metadata_to_tuple( + rec, index, *offsets, entry_heap, + update->info_bits, !thr_get_trx(thr)->in_rollback); + ut_ad(new_entry->n_fields + == ulint(index->n_fields) + + update->is_alter_metadata()); + } else { + new_entry = row_rec_to_index_entry(rec, index, *offsets, + entry_heap); + } + + /* The page containing the clustered index record + corresponding to new_entry is latched in mtr. If the + clustered index record is delete-marked, then its externally + stored fields cannot have been purged yet, because then the + purge would also have removed the clustered index record + itself. Thus the following call is safe. */ + row_upd_index_replace_new_col_vals_index_pos(new_entry, index, update, + entry_heap); + btr_cur_trim(new_entry, index, update, thr); + + /* We have to set appropriate extern storage bits in the new + record to be inserted: we have to remember which fields were such */ + + ut_ad(!page_is_comp(block->frame) || !rec_get_node_ptr_flag(rec)); + ut_ad(rec_offs_validate(rec, index, *offsets)); + + if ((flags & BTR_NO_UNDO_LOG_FLAG) + && rec_offs_any_extern(*offsets)) { + /* We are in a transaction rollback undoing a row + update: we must free possible externally stored fields + which got new values in the update, if they are not + inherited values. They can be inherited if we have + updated the primary key to another value, and then + update it back again. */ + + ut_ad(big_rec_vec == NULL); + ut_ad(dict_index_is_clust(index)); + ut_ad(thr_get_trx(thr)->in_rollback); + + DEBUG_SYNC_C("blob_rollback_middle"); + + btr_rec_free_updated_extern_fields( + index, rec, block, *offsets, update, true, mtr); + } + + ulint n_ext = index->is_primary() ? dtuple_get_n_ext(new_entry) : 0; + + if (page_zip_rec_needs_ext( + rec_get_converted_size(index, new_entry, n_ext), + page_is_comp(block->frame), + dict_index_get_n_fields(index), + block->zip_size()) + || (UNIV_UNLIKELY(update->is_alter_metadata()) + && !dfield_is_ext(dtuple_get_nth_field( + new_entry, + index->first_user_field())))) { + big_rec_vec = dtuple_convert_big_rec(index, update, new_entry, &n_ext); + if (UNIV_UNLIKELY(big_rec_vec == NULL)) { + + /* We cannot goto return_after_reservations, + because we may need to update the + IBUF_BITMAP_FREE bits, which was suppressed by + BTR_KEEP_IBUF_BITMAP. */ +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip + || page_zip_validate(page_zip, block->frame, + index)); +#endif /* UNIV_ZIP_DEBUG */ + index->table->space->release_free_extents(n_reserved); + err = DB_TOO_BIG_RECORD; + goto err_exit; + } + + ut_ad(page_is_leaf(block->frame)); + ut_ad(dict_index_is_clust(index)); + ut_ad(flags & BTR_KEEP_POS_FLAG); + } + + /* Do lock checking and undo logging */ + err = btr_cur_upd_lock_and_undo(flags, cursor, *offsets, + update, cmpl_info, + thr, mtr, &roll_ptr); + if (err != DB_SUCCESS) { + goto err_exit; + } + + if (optim_err == DB_OVERFLOW) { + + /* First reserve enough free space for the file segments + of the index tree, so that the update will not fail because + of lack of space */ + + uint32_t n_extents = uint32_t(cursor->tree_height / 16 + 3); + + if (!fsp_reserve_free_extents( + &n_reserved, index->table->space, n_extents, + flags & BTR_NO_UNDO_LOG_FLAG + ? FSP_CLEANING : FSP_NORMAL, + mtr)) { + err = DB_OUT_OF_FILE_SPACE; + goto err_exit; + } + } + + if (!(flags & BTR_KEEP_SYS_FLAG)) { + btr_cur_write_sys(new_entry, index, trx_id, roll_ptr); + } + + const ulint max_ins_size = page_zip + ? 0 : page_get_max_insert_size_after_reorganize(block->frame, + 1); + + if (UNIV_UNLIKELY(is_metadata)) { + ut_ad(new_entry->is_metadata()); + ut_ad(index->is_instant()); + /* This can be innobase_add_instant_try() performing a + subsequent instant ALTER TABLE, or its rollback by + row_undo_mod_clust_low(). */ + ut_ad(flags & BTR_NO_LOCKING_FLAG); + } else { + btr_search_update_hash_on_delete(cursor); + + /* Store state of explicit locks on rec on the page + infimum record, before deleting rec. The page infimum + acts as a dummy carrier of the locks, taking care also + of lock releases, before we can move the locks back on + the actual record. There is a special case: if we are + inserting on the root page and the insert causes a + call of btr_root_raise_and_insert. Therefore we cannot + in the lock system delete the lock structs set on the + root page even if the root page carries just node + pointers. */ + if (!dict_table_is_locking_disabled(index->table)) { + lock_rec_store_on_page_infimum(block, rec); + } + } + +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip || page_zip_validate(page_zip, block->frame, index)); +#endif /* UNIV_ZIP_DEBUG */ + page_cursor = btr_cur_get_page_cur(cursor); + + page_cur_delete_rec(page_cursor, index, *offsets, mtr); + + page_cur_move_to_prev(page_cursor); + + rec = btr_cur_insert_if_possible(cursor, new_entry, + offsets, offsets_heap, n_ext, mtr); + + if (rec) { + page_cursor->rec = rec; + + if (UNIV_UNLIKELY(is_metadata)) { + /* We must empty the PAGE_FREE list, because if this + was a rollback, the shortened metadata record + would have too many fields, and we would be unable to + know the size of the freed record. */ + btr_page_reorganize(page_cursor, index, mtr); + rec = page_cursor->rec; + rec_offs_make_valid(rec, index, true, *offsets); + if (page_cursor->block->page.id().page_no() + == index->page) { + btr_set_instant(page_cursor->block, *index, + mtr); + } + } else if (!dict_table_is_locking_disabled(index->table)) { + lock_rec_restore_from_page_infimum( + btr_cur_get_block(cursor), rec, block); + } + + if (!rec_get_deleted_flag(rec, rec_offs_comp(*offsets)) + || rec_is_alter_metadata(rec, *index)) { + /* The new inserted record owns its possible externally + stored fields */ + btr_cur_unmark_extern_fields(btr_cur_get_block(cursor), + rec, index, *offsets, mtr); + } else { + /* In delete-marked records, DB_TRX_ID must + always refer to an existing undo log record. */ + ut_ad(row_get_rec_trx_id(rec, index, *offsets)); + } + + bool adjust = big_rec_vec && (flags & BTR_KEEP_POS_FLAG); + ut_ad(!adjust || page_is_leaf(block->frame)); + + if (btr_cur_compress_if_useful(cursor, adjust, mtr)) { + if (adjust) { + rec_offs_make_valid(page_cursor->rec, index, + true, *offsets); + } + } else if (!dict_index_is_clust(index) + && page_is_leaf(block->frame)) { + /* Update the free bits in the insert buffer. + This is the same block which was skipped by + BTR_KEEP_IBUF_BITMAP. */ + if (page_zip) { + ut_ad(!index->table->is_temporary()); + ibuf_update_free_bits_zip(block, mtr); + } else if (!index->table->is_temporary()) { + ibuf_update_free_bits_low(block, max_ins_size, + mtr); + } + } + + if (!srv_read_only_mode + && !big_rec_vec + && page_is_leaf(block->frame) + && !dict_index_is_online_ddl(index)) { + + mtr_memo_release(mtr, dict_index_get_lock(index), + MTR_MEMO_X_LOCK | MTR_MEMO_SX_LOCK); + + /* NOTE: We cannot release root block latch here, because it + has segment header and already modified in most of cases.*/ + } + + err = DB_SUCCESS; + goto return_after_reservations; + } else { + /* If the page is compressed and it initially + compresses very well, and there is a subsequent insert + of a badly-compressing record, it is possible for + btr_cur_optimistic_update() to return DB_UNDERFLOW and + btr_cur_insert_if_possible() to return FALSE. */ + ut_a(page_zip || optim_err != DB_UNDERFLOW); + + /* Out of space: reset the free bits. + This is the same block which was skipped by + BTR_KEEP_IBUF_BITMAP. */ + if (!dict_index_is_clust(index) + && !index->table->is_temporary() + && page_is_leaf(block->frame)) { + ibuf_reset_free_bits(block); + } + } + + if (big_rec_vec != NULL) { + ut_ad(page_is_leaf(block->frame)); + ut_ad(dict_index_is_clust(index)); + ut_ad(flags & BTR_KEEP_POS_FLAG); + + /* btr_page_split_and_insert() in + btr_cur_pessimistic_insert() invokes + mtr_memo_release(mtr, index->lock, MTR_MEMO_SX_LOCK). + We must keep the index->lock when we created a + big_rec, so that row_upd_clust_rec() can store the + big_rec in the same mini-transaction. */ + + ut_ad(mtr->memo_contains_flagged(&index->lock, MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + mtr_sx_lock_index(index, mtr); + } + + /* Was the record to be updated positioned as the first user + record on its page? */ + was_first = page_cur_is_before_first(page_cursor); + + /* Lock checks and undo logging were already performed by + btr_cur_upd_lock_and_undo(). We do not try + btr_cur_optimistic_insert() because + btr_cur_insert_if_possible() already failed above. */ + + err = btr_cur_pessimistic_insert(BTR_NO_UNDO_LOG_FLAG + | BTR_NO_LOCKING_FLAG + | BTR_KEEP_SYS_FLAG, + cursor, offsets, offsets_heap, + new_entry, &rec, + &dummy_big_rec, n_ext, NULL, mtr); + ut_a(rec); + ut_a(err == DB_SUCCESS); + ut_a(dummy_big_rec == NULL); + ut_ad(rec_offs_validate(rec, cursor->index, *offsets)); + page_cursor->rec = rec; + + /* Multiple transactions cannot simultaneously operate on the + same temp-table in parallel. + max_trx_id is ignored for temp tables because it not required + for MVCC. */ + if (dict_index_is_sec_or_ibuf(index) + && !index->table->is_temporary()) { + /* Update PAGE_MAX_TRX_ID in the index page header. + It was not updated by btr_cur_pessimistic_insert() + because of BTR_NO_LOCKING_FLAG. */ + page_update_max_trx_id(btr_cur_get_block(cursor), + btr_cur_get_page_zip(cursor), + trx_id, mtr); + } + + if (!rec_get_deleted_flag(rec, rec_offs_comp(*offsets))) { + /* The new inserted record owns its possible externally + stored fields */ +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip || page_zip_validate(page_zip, block->frame, + index)); +#endif /* UNIV_ZIP_DEBUG */ + btr_cur_unmark_extern_fields(btr_cur_get_block(cursor), rec, + index, *offsets, mtr); + } else { + /* In delete-marked records, DB_TRX_ID must + always refer to an existing undo log record. */ + ut_ad(row_get_rec_trx_id(rec, index, *offsets)); + } + + if (UNIV_UNLIKELY(is_metadata)) { + /* We must empty the PAGE_FREE list, because if this + was a rollback, the shortened metadata record + would have too many fields, and we would be unable to + know the size of the freed record. */ + btr_page_reorganize(page_cursor, index, mtr); + rec = page_cursor->rec; + } else if (!dict_table_is_locking_disabled(index->table)) { + lock_rec_restore_from_page_infimum( + btr_cur_get_block(cursor), rec, block); + } + + /* If necessary, restore also the correct lock state for a new, + preceding supremum record created in a page split. While the old + record was nonexistent, the supremum might have inherited its locks + from a wrong record. */ + + if (!was_first && !dict_table_is_locking_disabled(index->table)) { + btr_cur_pess_upd_restore_supremum(btr_cur_get_block(cursor), + rec, mtr); + } + +return_after_reservations: +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip || page_zip_validate(btr_cur_get_page_zip(cursor), + btr_cur_get_page(cursor), index)); +#endif /* UNIV_ZIP_DEBUG */ + + index->table->space->release_free_extents(n_reserved); + *big_rec = big_rec_vec; + return(err); +} + +/*==================== B-TREE DELETE MARK AND UNMARK ===============*/ + +/** Modify the delete-mark flag of a record. +@tparam flag the value of the delete-mark flag +@param[in,out] block buffer block +@param[in,out] rec record on a physical index page +@param[in,out] mtr mini-transaction */ +template<bool flag> +void btr_rec_set_deleted(buf_block_t *block, rec_t *rec, mtr_t *mtr) +{ + if (page_rec_is_comp(rec)) + { + byte *b= &rec[-REC_NEW_INFO_BITS]; + const byte v= flag + ? (*b | REC_INFO_DELETED_FLAG) + : (*b & byte(~REC_INFO_DELETED_FLAG)); + if (*b == v); + else if (UNIV_LIKELY_NULL(block->page.zip.data)) + { + *b= v; + page_zip_rec_set_deleted(block, rec, flag, mtr); + } + else + mtr->write<1>(*block, b, v); + } + else + { + ut_ad(!block->page.zip.data); + byte *b= &rec[-REC_OLD_INFO_BITS]; + const byte v = flag + ? (*b | REC_INFO_DELETED_FLAG) + : (*b & byte(~REC_INFO_DELETED_FLAG)); + mtr->write<1,mtr_t::MAYBE_NOP>(*block, b, v); + } +} + +template void btr_rec_set_deleted<false>(buf_block_t *, rec_t *, mtr_t *); +template void btr_rec_set_deleted<true>(buf_block_t *, rec_t *, mtr_t *); + +/***********************************************************//** +Marks a clustered index record deleted. Writes an undo log record to +undo log on this delete marking. Writes in the trx id field the id +of the deleting transaction, and in the roll ptr field pointer to the +undo log record created. +@return DB_SUCCESS, DB_LOCK_WAIT, or error number */ +dberr_t +btr_cur_del_mark_set_clust_rec( +/*===========================*/ + buf_block_t* block, /*!< in/out: buffer block of the record */ + rec_t* rec, /*!< in/out: record */ + dict_index_t* index, /*!< in: clustered index of the record */ + const rec_offs* offsets,/*!< in: rec_get_offsets(rec) */ + que_thr_t* thr, /*!< in: query thread */ + const dtuple_t* entry, /*!< in: dtuple for the deleting record, also + contains the virtual cols if there are any */ + mtr_t* mtr) /*!< in/out: mini-transaction */ +{ + roll_ptr_t roll_ptr; + dberr_t err; + trx_t* trx; + + ut_ad(dict_index_is_clust(index)); + ut_ad(rec_offs_validate(rec, index, offsets)); + ut_ad(!!page_rec_is_comp(rec) == dict_table_is_comp(index->table)); + ut_ad(buf_block_get_frame(block) == page_align(rec)); + ut_ad(page_rec_is_leaf(rec)); + ut_ad(mtr->is_named_space(index->table->space)); + + if (rec_get_deleted_flag(rec, rec_offs_comp(offsets))) { + /* We may already have delete-marked this record + when executing an ON DELETE CASCADE operation. */ + ut_ad(row_get_rec_trx_id(rec, index, offsets) + == thr_get_trx(thr)->id); + return(DB_SUCCESS); + } + + err = lock_clust_rec_modify_check_and_lock(BTR_NO_LOCKING_FLAG, block, + rec, index, offsets, thr); + + if (err != DB_SUCCESS) { + + return(err); + } + + err = trx_undo_report_row_operation(thr, index, + entry, NULL, 0, rec, offsets, + &roll_ptr); + if (err != DB_SUCCESS) { + + return(err); + } + + /* The search latch is not needed here, because + the adaptive hash index does not depend on the delete-mark + and the delete-mark is being updated in place. */ + + btr_rec_set_deleted<true>(block, rec, mtr); + + trx = thr_get_trx(thr); + + DBUG_LOG("ib_cur", + "delete-mark clust " << index->table->name + << " (" << index->id << ") by " + << ib::hex(trx_get_id_for_print(trx)) << ": " + << rec_printer(rec, offsets).str()); + + if (dict_index_is_online_ddl(index)) { + row_log_table_delete(rec, index, offsets, NULL); + } + + btr_cur_upd_rec_sys(block, rec, index, offsets, trx, roll_ptr, mtr); + return(err); +} + +/*==================== B-TREE RECORD REMOVE =========================*/ + +/*************************************************************//** +Tries to compress a page of the tree if it seems useful. It is assumed +that mtr holds an x-latch on the tree and on the cursor page. To avoid +deadlocks, mtr must also own x-latches to brothers of page, if those +brothers exist. NOTE: it is assumed that the caller has reserved enough +free extents so that the compression will always succeed if done! +@return TRUE if compression occurred */ +ibool +btr_cur_compress_if_useful( +/*=======================*/ + btr_cur_t* cursor, /*!< in/out: cursor on the page to compress; + cursor does not stay valid if !adjust and + compression occurs */ + ibool adjust, /*!< in: TRUE if should adjust the + cursor position even if compression occurs */ + mtr_t* mtr) /*!< in/out: mini-transaction */ +{ + ut_ad(mtr->memo_contains_flagged(&cursor->index->lock, + MTR_MEMO_X_LOCK | MTR_MEMO_SX_LOCK)); + ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(cursor), + MTR_MEMO_PAGE_X_FIX)); + + if (cursor->index->is_spatial()) { + const trx_t* trx = cursor->rtr_info->thr + ? thr_get_trx(cursor->rtr_info->thr) + : NULL; + const buf_block_t* block = btr_cur_get_block(cursor); + + /* Check whether page lock prevents the compression */ + if (!lock_test_prdt_page_lock(trx, block->page.id())) { + return(false); + } + } + + return(btr_cur_compress_recommendation(cursor, mtr) + && btr_compress(cursor, adjust, mtr)); +} + +/*******************************************************//** +Removes the record on which the tree cursor is positioned on a leaf page. +It is assumed that the mtr has an x-latch on the page where the cursor is +positioned, but no latch on the whole tree. +@return TRUE if success, i.e., the page did not become too empty */ +ibool +btr_cur_optimistic_delete_func( +/*===========================*/ + btr_cur_t* cursor, /*!< in: cursor on leaf page, on the record to + delete; cursor stays valid: if deletion + succeeds, on function exit it points to the + successor of the deleted record */ +#ifdef UNIV_DEBUG + ulint flags, /*!< in: BTR_CREATE_FLAG or 0 */ +#endif /* UNIV_DEBUG */ + mtr_t* mtr) /*!< in: mtr; if this function returns + TRUE on a leaf page of a secondary + index, the mtr must be committed + before latching any further pages */ +{ + buf_block_t* block; + rec_t* rec; + mem_heap_t* heap = NULL; + rec_offs offsets_[REC_OFFS_NORMAL_SIZE]; + rec_offs* offsets = offsets_; + rec_offs_init(offsets_); + + ut_ad(flags == 0 || flags == BTR_CREATE_FLAG); + ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(cursor), + MTR_MEMO_PAGE_X_FIX)); + ut_ad(mtr->is_named_space(cursor->index->table->space)); + ut_ad(!cursor->index->is_dummy); + + /* This is intended only for leaf page deletions */ + + block = btr_cur_get_block(cursor); + + ut_ad(block->page.id().space() == cursor->index->table->space->id); + ut_ad(page_is_leaf(buf_block_get_frame(block))); + ut_ad(!dict_index_is_online_ddl(cursor->index) + || dict_index_is_clust(cursor->index) + || (flags & BTR_CREATE_FLAG)); + + rec = btr_cur_get_rec(cursor); + + offsets = rec_get_offsets(rec, cursor->index, offsets, + cursor->index->n_core_fields, + ULINT_UNDEFINED, &heap); + + const ibool no_compress_needed = !rec_offs_any_extern(offsets) + && btr_cur_can_delete_without_compress( + cursor, rec_offs_size(offsets), mtr); + + if (!no_compress_needed) { + /* prefetch siblings of the leaf for the pessimistic + operation. */ + btr_cur_prefetch_siblings(block, cursor->index); + goto func_exit; + } + + if (UNIV_UNLIKELY(block->page.id().page_no() == cursor->index->page + && page_get_n_recs(block->frame) == 1 + + (cursor->index->is_instant() + && !rec_is_metadata(rec, *cursor->index)) + && !cursor->index->must_avoid_clear_instant_add())) { + /* The whole index (and table) becomes logically empty. + Empty the whole page. That is, if we are deleting the + only user record, also delete the metadata record + if one exists for instant ADD COLUMN (not generic ALTER TABLE). + If we are deleting the metadata record and the + table becomes empty, clean up the whole page. */ + dict_index_t* index = cursor->index; + const rec_t* first_rec = page_rec_get_next_const( + page_get_infimum_rec(block->frame)); + ut_ad(!index->is_instant() + || rec_is_metadata(first_rec, *index)); + const bool is_metadata = rec_is_metadata(rec, *index); + /* We can remove the metadata when rolling back an + instant ALTER TABLE operation, or when deleting the + last user record on the page such that only metadata for + instant ADD COLUMN (not generic ALTER TABLE) remains. */ + const bool empty_table = is_metadata + || !index->is_instant() + || (first_rec != rec + && rec_is_add_metadata(first_rec, *index)); + if (UNIV_LIKELY(empty_table)) { + if (UNIV_LIKELY(!is_metadata)) { + lock_update_delete(block, rec); + } + btr_page_empty(block, buf_block_get_page_zip(block), + index, 0, mtr); + if (index->is_instant()) { + /* MDEV-17383: free metadata BLOBs! */ + index->clear_instant_alter(); + } + page_cur_set_after_last(block, + btr_cur_get_page_cur(cursor)); + goto func_exit; + } + } + + { + page_t* page = buf_block_get_frame(block); + page_zip_des_t* page_zip= buf_block_get_page_zip(block); + + if (UNIV_UNLIKELY(rec_get_info_bits(rec, page_rec_is_comp(rec)) + & REC_INFO_MIN_REC_FLAG)) { + /* This should be rolling back instant ADD COLUMN. + If this is a recovered transaction, then + index->is_instant() will hold until the + insert into SYS_COLUMNS is rolled back. */ + ut_ad(cursor->index->table->supports_instant()); + ut_ad(cursor->index->is_primary()); + ut_ad(!page_zip); + page_cur_delete_rec(btr_cur_get_page_cur(cursor), + cursor->index, offsets, mtr); + /* We must empty the PAGE_FREE list, because + after rollback, this deleted metadata record + would have too many fields, and we would be + unable to know the size of the freed record. */ + btr_page_reorganize(btr_cur_get_page_cur(cursor), + cursor->index, mtr); + goto func_exit; + } else { + lock_update_delete(block, rec); + + btr_search_update_hash_on_delete(cursor); + } + + if (page_zip) { +#ifdef UNIV_ZIP_DEBUG + ut_a(page_zip_validate(page_zip, page, cursor->index)); +#endif /* UNIV_ZIP_DEBUG */ + page_cur_delete_rec(btr_cur_get_page_cur(cursor), + cursor->index, offsets, mtr); +#ifdef UNIV_ZIP_DEBUG + ut_a(page_zip_validate(page_zip, page, cursor->index)); +#endif /* UNIV_ZIP_DEBUG */ + + /* On compressed pages, the IBUF_BITMAP_FREE + space is not affected by deleting (purging) + records, because it is defined as the minimum + of space available *without* reorganize, and + space available in the modification log. */ + } else { + const ulint max_ins + = page_get_max_insert_size_after_reorganize( + page, 1); + + page_cur_delete_rec(btr_cur_get_page_cur(cursor), + cursor->index, offsets, mtr); + + /* The change buffer does not handle inserts + into non-leaf pages, into clustered indexes, + or into the change buffer. */ + if (!dict_index_is_clust(cursor->index) + && !cursor->index->table->is_temporary() + && !dict_index_is_ibuf(cursor->index)) { + ibuf_update_free_bits_low(block, max_ins, mtr); + } + } + } + +func_exit: + if (UNIV_LIKELY_NULL(heap)) { + mem_heap_free(heap); + } + + return(no_compress_needed); +} + +/*************************************************************//** +Removes the record on which the tree cursor is positioned. Tries +to compress the page if its fillfactor drops below a threshold +or if it is the only page on the level. It is assumed that mtr holds +an x-latch on the tree and on the cursor page. To avoid deadlocks, +mtr must also own x-latches to brothers of page, if those brothers +exist. +@return TRUE if compression occurred and FALSE if not or something +wrong. */ +ibool +btr_cur_pessimistic_delete( +/*=======================*/ + dberr_t* err, /*!< out: DB_SUCCESS or DB_OUT_OF_FILE_SPACE; + the latter may occur because we may have + to update node pointers on upper levels, + and in the case of variable length keys + these may actually grow in size */ + ibool has_reserved_extents, /*!< in: TRUE if the + caller has already reserved enough free + extents so that he knows that the operation + will succeed */ + btr_cur_t* cursor, /*!< in: cursor on the record to delete; + if compression does not occur, the cursor + stays valid: it points to successor of + deleted record on function exit */ + ulint flags, /*!< in: BTR_CREATE_FLAG or 0 */ + bool rollback,/*!< in: performing rollback? */ + mtr_t* mtr) /*!< in: mtr */ +{ + buf_block_t* block; + page_t* page; + page_zip_des_t* page_zip; + dict_index_t* index; + rec_t* rec; + uint32_t n_reserved = 0; + bool success; + ibool ret = FALSE; + mem_heap_t* heap; + rec_offs* offsets; +#ifdef UNIV_DEBUG + bool parent_latched = false; +#endif /* UNIV_DEBUG */ + + block = btr_cur_get_block(cursor); + page = buf_block_get_frame(block); + index = btr_cur_get_index(cursor); + + ut_ad(flags == 0 || flags == BTR_CREATE_FLAG); + ut_ad(!dict_index_is_online_ddl(index) + || dict_index_is_clust(index) + || (flags & BTR_CREATE_FLAG)); + ut_ad(mtr->memo_contains_flagged(&index->lock, MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + ut_ad(mtr->memo_contains_flagged(block, MTR_MEMO_PAGE_X_FIX)); + ut_ad(mtr->is_named_space(index->table->space)); + ut_ad(!index->is_dummy); + ut_ad(block->page.id().space() == index->table->space->id); + + if (!has_reserved_extents) { + /* First reserve enough free space for the file segments + of the index tree, so that the node pointer updates will + not fail because of lack of space */ + + uint32_t n_extents = uint32_t(cursor->tree_height / 32 + 1); + + success = fsp_reserve_free_extents(&n_reserved, + index->table->space, + n_extents, + FSP_CLEANING, mtr); + if (!success) { + *err = DB_OUT_OF_FILE_SPACE; + + return(FALSE); + } + } + + heap = mem_heap_create(1024); + rec = btr_cur_get_rec(cursor); + page_zip = buf_block_get_page_zip(block); +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip || page_zip_validate(page_zip, page, index)); +#endif /* UNIV_ZIP_DEBUG */ + + offsets = rec_get_offsets(rec, index, NULL, page_is_leaf(page) + ? index->n_core_fields : 0, + ULINT_UNDEFINED, &heap); + + if (rec_offs_any_extern(offsets)) { + btr_rec_free_externally_stored_fields(index, + rec, offsets, block, + rollback, mtr); +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip || page_zip_validate(page_zip, page, index)); +#endif /* UNIV_ZIP_DEBUG */ + } + + rec_t* next_rec = NULL; + bool min_mark_next_rec = false; + + if (page_is_leaf(page)) { + const bool is_metadata = rec_is_metadata( + rec, page_rec_is_comp(rec)); + if (UNIV_UNLIKELY(is_metadata)) { + /* This should be rolling back instant ALTER TABLE. + If this is a recovered transaction, then + index->is_instant() will hold until the + insert into SYS_COLUMNS is rolled back. */ + ut_ad(rollback); + ut_ad(index->table->supports_instant()); + ut_ad(index->is_primary()); + } else if (flags == 0) { + lock_update_delete(block, rec); + } + + if (block->page.id().page_no() != index->page) { + if (page_get_n_recs(page) < 2) { + goto discard_page; + } + } else if (page_get_n_recs(page) == 1 + + (index->is_instant() && !is_metadata) + && !index->must_avoid_clear_instant_add()) { + /* The whole index (and table) becomes logically empty. + Empty the whole page. That is, if we are deleting the + only user record, also delete the metadata record + if one exists for instant ADD COLUMN + (not generic ALTER TABLE). + If we are deleting the metadata record + (in the rollback of instant ALTER TABLE) and the + table becomes empty, clean up the whole page. */ + + const rec_t* first_rec = page_rec_get_next_const( + page_get_infimum_rec(page)); + ut_ad(!index->is_instant() + || rec_is_metadata(first_rec, *index)); + if (is_metadata || !index->is_instant() + || (first_rec != rec + && rec_is_add_metadata(first_rec, *index))) { + btr_page_empty(block, page_zip, index, 0, mtr); + if (index->is_instant()) { + /* MDEV-17383: free metadata BLOBs! */ + index->clear_instant_alter(); + } + page_cur_set_after_last( + block, + btr_cur_get_page_cur(cursor)); + ret = TRUE; + goto return_after_reservations; + } + } + + if (UNIV_LIKELY(!is_metadata)) { + btr_search_update_hash_on_delete(cursor); + } else { + page_cur_delete_rec(btr_cur_get_page_cur(cursor), + index, offsets, mtr); + /* We must empty the PAGE_FREE list, because + after rollback, this deleted metadata record + would carry too many fields, and we would be + unable to know the size of the freed record. */ + btr_page_reorganize(btr_cur_get_page_cur(cursor), + index, mtr); + ut_ad(!ret); + goto return_after_reservations; + } + } else if (UNIV_UNLIKELY(page_rec_is_first(rec, page))) { + if (page_rec_is_last(rec, page)) { +discard_page: + ut_ad(page_get_n_recs(page) == 1); + /* If there is only one record, drop + the whole page. */ + + btr_discard_page(cursor, mtr); + + ret = TRUE; + goto return_after_reservations; + } + + next_rec = page_rec_get_next(rec); + + if (!page_has_prev(page)) { + /* If we delete the leftmost node pointer on a + non-leaf level, we must mark the new leftmost node + pointer as the predefined minimum record */ + + min_mark_next_rec = true; + } else if (index->is_spatial()) { + /* For rtree, if delete the leftmost node pointer, + we need to update parent page. */ + rtr_mbr_t father_mbr; + rec_t* father_rec; + btr_cur_t father_cursor; + rec_offs* offsets; + bool upd_ret; + ulint len; + + rtr_page_get_father_block(NULL, heap, index, + block, mtr, NULL, + &father_cursor); + offsets = rec_get_offsets( + btr_cur_get_rec(&father_cursor), index, NULL, + 0, ULINT_UNDEFINED, &heap); + + father_rec = btr_cur_get_rec(&father_cursor); + rtr_read_mbr(rec_get_nth_field( + father_rec, offsets, 0, &len), &father_mbr); + + upd_ret = rtr_update_mbr_field(&father_cursor, offsets, + NULL, page, &father_mbr, + next_rec, mtr); + + if (!upd_ret) { + *err = DB_ERROR; + + mem_heap_free(heap); + return(FALSE); + } + + ut_d(parent_latched = true); + } else { + /* Otherwise, if we delete the leftmost node pointer + on a page, we have to change the parent node pointer + so that it is equal to the new leftmost node pointer + on the page */ + btr_cur_t cursor; + btr_page_get_father(index, block, mtr, &cursor); + btr_cur_node_ptr_delete(&cursor, mtr); + const ulint level = btr_page_get_level(page); + // FIXME: reuse the node_ptr from above + dtuple_t* node_ptr = dict_index_build_node_ptr( + index, next_rec, block->page.id().page_no(), + heap, level); + + btr_insert_on_non_leaf_level( + flags, index, level + 1, node_ptr, mtr); + + ut_d(parent_latched = true); + } + } + + /* SPATIAL INDEX never use SX locks; we can allow page merges + while holding X lock on the spatial index tree. + Do not allow merges of non-leaf B-tree pages unless it is + safe to do so. */ + { + const bool allow_merge = page_is_leaf(page) + || dict_index_is_spatial(index) + || btr_cur_will_modify_tree( + index, page, BTR_INTENTION_DELETE, rec, + btr_node_ptr_max_size(index), + block->zip_size(), mtr); + page_cur_delete_rec(btr_cur_get_page_cur(cursor), index, + offsets, mtr); + + if (min_mark_next_rec) { + btr_set_min_rec_mark(next_rec, *block, mtr); + } + +#ifdef UNIV_ZIP_DEBUG + ut_a(!page_zip || page_zip_validate(page_zip, page, index)); +#endif /* UNIV_ZIP_DEBUG */ + + ut_ad(!parent_latched + || btr_check_node_ptr(index, block, mtr)); + + if (!ret && btr_cur_compress_recommendation(cursor, mtr)) { + if (UNIV_LIKELY(allow_merge)) { + ret = btr_cur_compress_if_useful( + cursor, FALSE, mtr); + } else { + ib::warn() << "Not merging page " + << block->page.id() + << " in index " << index->name + << " of " << index->table->name; + ut_ad("MDEV-14637" == 0); + } + } + } + +return_after_reservations: + *err = DB_SUCCESS; + + mem_heap_free(heap); + + if (!srv_read_only_mode + && page_is_leaf(page) + && !dict_index_is_online_ddl(index)) { + + mtr_memo_release(mtr, dict_index_get_lock(index), + MTR_MEMO_X_LOCK | MTR_MEMO_SX_LOCK); + + /* NOTE: We cannot release root block latch here, because it + has segment header and already modified in most of cases.*/ + } + + index->table->space->release_free_extents(n_reserved); + return(ret); +} + +/** Delete the node pointer in a parent page. +@param[in,out] parent cursor pointing to parent record +@param[in,out] mtr mini-transaction */ +void btr_cur_node_ptr_delete(btr_cur_t* parent, mtr_t* mtr) +{ + ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(parent), + MTR_MEMO_PAGE_X_FIX)); + dberr_t err; + ibool compressed = btr_cur_pessimistic_delete(&err, TRUE, parent, + BTR_CREATE_FLAG, false, + mtr); + ut_a(err == DB_SUCCESS); + if (!compressed) { + btr_cur_compress_if_useful(parent, FALSE, mtr); + } +} + +/*******************************************************************//** +Adds path information to the cursor for the current page, for which +the binary search has been performed. */ +static +void +btr_cur_add_path_info( +/*==================*/ + btr_cur_t* cursor, /*!< in: cursor positioned on a page */ + ulint height, /*!< in: height of the page in tree; + 0 means leaf node */ + ulint root_height) /*!< in: root node height in tree */ +{ + btr_path_t* slot; + + ut_a(cursor->path_arr); + + if (root_height >= BTR_PATH_ARRAY_N_SLOTS - 1) { + /* Do nothing; return empty path */ + + slot = cursor->path_arr; + slot->nth_rec = ULINT_UNDEFINED; + + return; + } + + if (height == 0) { + /* Mark end of slots for path */ + slot = cursor->path_arr + root_height + 1; + slot->nth_rec = ULINT_UNDEFINED; + } + + slot = cursor->path_arr + (root_height - height); + + const buf_block_t* block = btr_cur_get_block(cursor); + + slot->nth_rec = page_rec_get_n_recs_before(btr_cur_get_rec(cursor)); + slot->n_recs = page_get_n_recs(block->frame); + slot->page_no = block->page.id().page_no(); + slot->page_level = btr_page_get_level(block->frame); +} + +/*******************************************************************//** +Estimate the number of rows between slot1 and slot2 for any level on a +B-tree. This function starts from slot1->page and reads a few pages to +the right, counting their records. If we reach slot2->page quickly then +we know exactly how many records there are between slot1 and slot2 and +we set is_n_rows_exact to TRUE. If we cannot reach slot2->page quickly +then we calculate the average number of records in the pages scanned +so far and assume that all pages that we did not scan up to slot2->page +contain the same number of records, then we multiply that average to +the number of pages between slot1->page and slot2->page (which is +n_rows_on_prev_level). In this case we set is_n_rows_exact to FALSE. +@return number of rows, not including the borders (exact or estimated) */ +static +ha_rows +btr_estimate_n_rows_in_range_on_level( +/*==================================*/ + dict_index_t* index, /*!< in: index */ + btr_path_t* slot1, /*!< in: left border */ + btr_path_t* slot2, /*!< in: right border */ + ha_rows n_rows_on_prev_level, /*!< in: number of rows + on the previous level for the + same descend paths; used to + determine the number of pages + on this level */ + bool* is_n_rows_exact) /*!< out: TRUE if the returned + value is exact i.e. not an + estimation */ +{ + ha_rows n_rows = 0; + uint n_pages_read = 0; + ulint level; + + /* Assume by default that we will scan all pages between + slot1->page_no and slot2->page_no. */ + *is_n_rows_exact = true; + + /* Add records from slot1->page_no which are to the right of + the record which serves as a left border of the range, if any + (we don't include the record itself in this count). */ + if (slot1->nth_rec <= slot1->n_recs) { + n_rows += slot1->n_recs - slot1->nth_rec; + } + + /* Add records from slot2->page_no which are to the left of + the record which servers as a right border of the range, if any + (we don't include the record itself in this count). */ + if (slot2->nth_rec > 1) { + n_rows += slot2->nth_rec - 1; + } + + /* Count the records in the pages between slot1->page_no and + slot2->page_no (non inclusive), if any. */ + + /* Do not read more than this number of pages in order not to hurt + performance with this code which is just an estimation. If we read + this many pages before reaching slot2->page_no then we estimate the + average from the pages scanned so far. */ +# define N_PAGES_READ_LIMIT 10 + + const fil_space_t* space = index->table->space; + page_id_t page_id(space->id, slot1->page_no); + const ulint zip_size = space->zip_size(); + + level = slot1->page_level; + + do { + mtr_t mtr; + page_t* page; + buf_block_t* block; + dberr_t err=DB_SUCCESS; + + mtr_start(&mtr); + + /* Fetch the page. Because we are not holding the + index->lock, the tree may have changed and we may be + attempting to read a page that is no longer part of + the B-tree. We pass BUF_GET_POSSIBLY_FREED in order to + silence a debug assertion about this. */ + block = buf_page_get_gen(page_id, zip_size, RW_S_LATCH, + NULL, BUF_GET_POSSIBLY_FREED, + __FILE__, __LINE__, &mtr, &err); + + ut_ad((block != NULL) == (err == DB_SUCCESS)); + + if (!block) { + if (err == DB_DECRYPTION_FAILED) { + ib_push_warning((void *)NULL, + DB_DECRYPTION_FAILED, + "Table %s is encrypted but encryption service or" + " used key_id is not available. " + " Can't continue reading table.", + index->table->name.m_name); + index->table->file_unreadable = true; + } + + mtr_commit(&mtr); + goto inexact; + } + + page = buf_block_get_frame(block); + + /* It is possible that the tree has been reorganized in the + meantime and this is a different page. If this happens the + calculated estimate will be bogus, which is not fatal as + this is only an estimate. We are sure that a page with + page_no exists because InnoDB never frees pages, only + reuses them. */ + if (!fil_page_index_page_check(page) + || btr_page_get_index_id(page) != index->id + || btr_page_get_level(page) != level) { + + /* The page got reused for something else */ + mtr_commit(&mtr); + goto inexact; + } + + /* It is possible but highly unlikely that the page was + originally written by an old version of InnoDB that did + not initialize FIL_PAGE_TYPE on other than B-tree pages. + For example, this could be an almost-empty BLOB page + that happens to contain the magic values in the fields + that we checked above. */ + + n_pages_read++; + + if (page_id.page_no() != slot1->page_no) { + /* Do not count the records on slot1->page_no, + we already counted them before this loop. */ + n_rows += page_get_n_recs(page); + } + + page_id.set_page_no(btr_page_get_next(page)); + + mtr_commit(&mtr); + + if (n_pages_read == N_PAGES_READ_LIMIT + || page_id.page_no() == FIL_NULL) { + /* Either we read too many pages or + we reached the end of the level without passing + through slot2->page_no, the tree must have changed + in the meantime */ + goto inexact; + } + + } while (page_id.page_no() != slot2->page_no); + + return(n_rows); + +inexact: + + *is_n_rows_exact = false; + + /* We did interrupt before reaching slot2->page */ + + if (n_pages_read > 0) { + /* The number of pages on this level is + n_rows_on_prev_level, multiply it by the + average number of recs per page so far */ + n_rows = n_rows_on_prev_level * n_rows / n_pages_read; + } else { + /* The tree changed before we could even + start with slot1->page_no */ + n_rows = 10; + } + + return(n_rows); +} + +/** If the tree gets changed too much between the two dives for the left +and right boundary then btr_estimate_n_rows_in_range_low() will retry +that many times before giving up and returning the value stored in +rows_in_range_arbitrary_ret_val. */ +static const unsigned rows_in_range_max_retries = 4; + +/** We pretend that a range has that many records if the tree keeps changing +for rows_in_range_max_retries retries while we try to estimate the records +in a given range. */ +static const ha_rows rows_in_range_arbitrary_ret_val = 10; + +/** Estimates the number of rows in a given index range. +@param[in] index index +@param[in] tuple1 range start +@param[in] tuple2 range end +@param[in] nth_attempt if the tree gets modified too much while +we are trying to analyze it, then we will retry (this function will call +itself, incrementing this parameter) +@return estimated number of rows; if after rows_in_range_max_retries +retries the tree keeps changing, then we will just return +rows_in_range_arbitrary_ret_val as a result (if +nth_attempt >= rows_in_range_max_retries and the tree is modified between +the two dives). */ +static +ha_rows +btr_estimate_n_rows_in_range_low( + dict_index_t* index, + btr_pos_t* tuple1, + btr_pos_t* tuple2, + unsigned nth_attempt) +{ + btr_path_t path1[BTR_PATH_ARRAY_N_SLOTS]; + btr_path_t path2[BTR_PATH_ARRAY_N_SLOTS]; + btr_cur_t cursor; + btr_path_t* slot1; + btr_path_t* slot2; + bool diverged; + bool diverged_lot; + ulint divergence_level; + ha_rows n_rows; + bool is_n_rows_exact; + ulint i; + mtr_t mtr; + ha_rows table_n_rows; + page_cur_mode_t mode2= tuple2->mode; + + table_n_rows = dict_table_get_n_rows(index->table); + + /* Below we dive to the two records specified by tuple1 and tuple2 and + we remember the entire dive paths from the tree root. The place where + the tuple1 path ends on the leaf level we call "left border" of our + interval and the place where the tuple2 path ends on the leaf level - + "right border". We take care to either include or exclude the interval + boundaries depending on whether <, <=, > or >= was specified. For + example if "5 < x AND x <= 10" then we should not include the left + boundary, but should include the right one. */ + + mtr_start(&mtr); + + cursor.path_arr = path1; + + bool should_count_the_left_border; + + if (dtuple_get_n_fields(tuple1->tuple) > 0) { + + btr_cur_search_to_nth_level(index, 0, tuple1->tuple, + tuple1->mode, + BTR_SEARCH_LEAF | BTR_ESTIMATE, + &cursor, 0, + __FILE__, __LINE__, &mtr); + + ut_ad(!page_rec_is_infimum(btr_cur_get_rec(&cursor))); + + /* We should count the border if there are any records to + match the criteria, i.e. if the maximum record on the tree is + 5 and x > 3 is specified then the cursor will be positioned at + 5 and we should count the border, but if x > 7 is specified, + then the cursor will be positioned at 'sup' on the rightmost + leaf page in the tree and we should not count the border. */ + should_count_the_left_border + = !page_rec_is_supremum(btr_cur_get_rec(&cursor)); + } else { + dberr_t err = DB_SUCCESS; + + err = btr_cur_open_at_index_side(true, index, + BTR_SEARCH_LEAF | BTR_ESTIMATE, + &cursor, 0, &mtr); + + if (err != DB_SUCCESS) { + ib::warn() << " Error code: " << err + << " btr_estimate_n_rows_in_range_low " + << " called from file: " + << __FILE__ << " line: " << __LINE__ + << " table: " << index->table->name + << " index: " << index->name; + } + + ut_ad(page_rec_is_infimum(btr_cur_get_rec(&cursor))); + + /* The range specified is wihout a left border, just + 'x < 123' or 'x <= 123' and btr_cur_open_at_index_side() + positioned the cursor on the infimum record on the leftmost + page, which must not be counted. */ + should_count_the_left_border = false; + } + + tuple1->page_id= cursor.page_cur.block->page.id(); + + mtr_commit(&mtr); + + if (!index->is_readable()) { + return 0; + } + + mtr_start(&mtr); + + cursor.path_arr = path2; + + bool should_count_the_right_border; + + if (dtuple_get_n_fields(tuple2->tuple) > 0) { + + btr_cur_search_to_nth_level(index, 0, tuple2->tuple, + mode2, + BTR_SEARCH_LEAF | BTR_ESTIMATE, + &cursor, 0, + __FILE__, __LINE__, &mtr); + + const rec_t* rec = btr_cur_get_rec(&cursor); + + ut_ad(!(mode2 == PAGE_CUR_L && page_rec_is_supremum(rec))); + + should_count_the_right_border + = (mode2 == PAGE_CUR_LE /* if the range is '<=' */ + /* and the record was found */ + && cursor.low_match >= dtuple_get_n_fields(tuple2->tuple)) + || (mode2 == PAGE_CUR_L /* or if the range is '<' */ + /* and there are any records to match the criteria, + i.e. if the minimum record on the tree is 5 and + x < 7 is specified then the cursor will be + positioned at 5 and we should count the border, but + if x < 2 is specified, then the cursor will be + positioned at 'inf' and we should not count the + border */ + && !page_rec_is_infimum(rec)); + /* Notice that for "WHERE col <= 'foo'" MySQL passes to + ha_innobase::records_in_range(): + min_key=NULL (left-unbounded) which is expected + max_key='foo' flag=HA_READ_AFTER_KEY (PAGE_CUR_G), which is + unexpected - one would expect + flag=HA_READ_KEY_OR_PREV (PAGE_CUR_LE). In this case the + cursor will be positioned on the first record to the right of + the requested one (can also be positioned on the 'sup') and + we should not count the right border. */ + } else { + dberr_t err = DB_SUCCESS; + + err = btr_cur_open_at_index_side(false, index, + BTR_SEARCH_LEAF | BTR_ESTIMATE, + &cursor, 0, &mtr); + + if (err != DB_SUCCESS) { + ib::warn() << " Error code: " << err + << " btr_estimate_n_rows_in_range_low " + << " called from file: " + << __FILE__ << " line: " << __LINE__ + << " table: " << index->table->name + << " index: " << index->name; + } + + ut_ad(page_rec_is_supremum(btr_cur_get_rec(&cursor))); + + /* The range specified is wihout a right border, just + 'x > 123' or 'x >= 123' and btr_cur_open_at_index_side() + positioned the cursor on the supremum record on the rightmost + page, which must not be counted. */ + should_count_the_right_border = false; + } + + tuple2->page_id= cursor.page_cur.block->page.id(); + + mtr_commit(&mtr); + + /* We have the path information for the range in path1 and path2 */ + + n_rows = 0; + is_n_rows_exact = true; + + /* This becomes true when the two paths do not pass through the + same pages anymore. */ + diverged = false; + + /* This becomes true when the paths are not the same or adjacent + any more. This means that they pass through the same or + neighboring-on-the-same-level pages only. */ + diverged_lot = false; + + /* This is the level where paths diverged a lot. */ + divergence_level = 1000000; + + for (i = 0; ; i++) { + ut_ad(i < BTR_PATH_ARRAY_N_SLOTS); + + slot1 = path1 + i; + slot2 = path2 + i; + + if (slot1->nth_rec == ULINT_UNDEFINED + || slot2->nth_rec == ULINT_UNDEFINED) { + + /* Here none of the borders were counted. For example, + if on the leaf level we descended to: + (inf, a, b, c, d, e, f, sup) + ^ ^ + path1 path2 + then n_rows will be 2 (c and d). */ + + if (is_n_rows_exact) { + /* Only fiddle to adjust this off-by-one + if the number is exact, otherwise we do + much grosser adjustments below. */ + + btr_path_t* last1 = &path1[i - 1]; + btr_path_t* last2 = &path2[i - 1]; + + /* If both paths end up on the same record on + the leaf level. */ + if (last1->page_no == last2->page_no + && last1->nth_rec == last2->nth_rec) { + + /* n_rows can be > 0 here if the paths + were first different and then converged + to the same record on the leaf level. + For example: + SELECT ... LIKE 'wait/synch/rwlock%' + mode1=PAGE_CUR_GE, + tuple1="wait/synch/rwlock" + path1[0]={nth_rec=58, n_recs=58, + page_no=3, page_level=1} + path1[1]={nth_rec=56, n_recs=55, + page_no=119, page_level=0} + + mode2=PAGE_CUR_G + tuple2="wait/synch/rwlock" + path2[0]={nth_rec=57, n_recs=57, + page_no=3, page_level=1} + path2[1]={nth_rec=56, n_recs=55, + page_no=119, page_level=0} */ + + /* If the range is such that we should + count both borders, then avoid + counting that record twice - once as a + left border and once as a right + border. */ + if (should_count_the_left_border + && should_count_the_right_border) { + + n_rows = 1; + } else { + /* Some of the borders should + not be counted, e.g. [3,3). */ + n_rows = 0; + } + } else { + if (should_count_the_left_border) { + n_rows++; + } + + if (should_count_the_right_border) { + n_rows++; + } + } + } + + if (i > divergence_level + 1 && !is_n_rows_exact) { + /* In trees whose height is > 1 our algorithm + tends to underestimate: multiply the estimate + by 2: */ + + n_rows = n_rows * 2; + } + + DBUG_EXECUTE_IF("bug14007649", return(n_rows);); + + /* Do not estimate the number of rows in the range + to over 1 / 2 of the estimated rows in the whole + table */ + + if (n_rows > table_n_rows / 2 && !is_n_rows_exact) { + + n_rows = table_n_rows / 2; + + /* If there are just 0 or 1 rows in the table, + then we estimate all rows are in the range */ + + if (n_rows == 0) { + n_rows = table_n_rows; + } + } + + return(n_rows); + } + + if (!diverged && slot1->nth_rec != slot2->nth_rec) { + + /* If both slots do not point to the same page, + this means that the tree must have changed between + the dive for slot1 and the dive for slot2 at the + beginning of this function. */ + if (slot1->page_no != slot2->page_no + || slot1->page_level != slot2->page_level) { + + /* If the tree keeps changing even after a + few attempts, then just return some arbitrary + number. */ + if (nth_attempt >= rows_in_range_max_retries) { + return(rows_in_range_arbitrary_ret_val); + } + + return btr_estimate_n_rows_in_range_low( + index, tuple1, tuple2, + nth_attempt + 1); + } + + diverged = true; + + if (slot1->nth_rec < slot2->nth_rec) { + /* We do not count the borders (nor the left + nor the right one), thus "- 1". */ + n_rows = slot2->nth_rec - slot1->nth_rec - 1; + + if (n_rows > 0) { + /* There is at least one row between + the two borders pointed to by slot1 + and slot2, so on the level below the + slots will point to non-adjacent + pages. */ + diverged_lot = true; + divergence_level = i; + } + } else { + /* It is possible that + slot1->nth_rec >= slot2->nth_rec + if, for example, we have a single page + tree which contains (inf, 5, 6, supr) + and we select where x > 20 and x < 30; + in this case slot1->nth_rec will point + to the supr record and slot2->nth_rec + will point to 6. */ + n_rows = 0; + should_count_the_left_border = false; + should_count_the_right_border = false; + } + + } else if (diverged && !diverged_lot) { + + if (slot1->nth_rec < slot1->n_recs + || slot2->nth_rec > 1) { + + diverged_lot = true; + divergence_level = i; + + n_rows = 0; + + if (slot1->nth_rec < slot1->n_recs) { + n_rows += slot1->n_recs + - slot1->nth_rec; + } + + if (slot2->nth_rec > 1) { + n_rows += slot2->nth_rec - 1; + } + } + } else if (diverged_lot) { + + n_rows = btr_estimate_n_rows_in_range_on_level( + index, slot1, slot2, n_rows, + &is_n_rows_exact); + } + } +} + +/** Estimates the number of rows in a given index range. +@param[in] index index +@param[in] tuple1 range start, may also be empty tuple +@param[in] mode1 search mode for range start +@param[in] tuple2 range end, may also be empty tuple +@param[in] mode2 search mode for range end +@return estimated number of rows */ +ha_rows +btr_estimate_n_rows_in_range( + dict_index_t* index, + btr_pos_t *tuple1, + btr_pos_t *tuple2) +{ + return btr_estimate_n_rows_in_range_low( + index, tuple1, tuple2, 1); +} + +/*******************************************************************//** +Record the number of non_null key values in a given index for +each n-column prefix of the index where 1 <= n <= dict_index_get_n_unique(index). +The estimates are eventually stored in the array: +index->stat_n_non_null_key_vals[], which is indexed from 0 to n-1. */ +static +void +btr_record_not_null_field_in_rec( +/*=============================*/ + ulint n_unique, /*!< in: dict_index_get_n_unique(index), + number of columns uniquely determine + an index entry */ + const rec_offs* offsets, /*!< in: rec_get_offsets(rec, index), + its size could be for all fields or + that of "n_unique" */ + ib_uint64_t* n_not_null) /*!< in/out: array to record number of + not null rows for n-column prefix */ +{ + ulint i; + + ut_ad(rec_offs_n_fields(offsets) >= n_unique); + + if (n_not_null == NULL) { + return; + } + + for (i = 0; i < n_unique; i++) { + if (rec_offs_nth_sql_null(offsets, i)) { + break; + } + + n_not_null[i]++; + } +} + +/** Estimates the number of different key values in a given index, for +each n-column prefix of the index where 1 <= n <= dict_index_get_n_unique(index). +The estimates are stored in the array index->stat_n_diff_key_vals[] (indexed +0..n_uniq-1) and the number of pages that were sampled is saved in +result.n_sample_sizes[]. +If innodb_stats_method is nulls_ignored, we also record the number of +non-null values for each prefix and stored the estimates in +array result.n_non_null_key_vals. +@param[in] index index +@return vector with statistics information +empty vector if the index is unavailable. */ +std::vector<index_field_stats_t> +btr_estimate_number_of_different_key_vals(dict_index_t* index) +{ + btr_cur_t cursor; + page_t* page; + rec_t* rec; + ulint n_cols; + ib_uint64_t* n_diff; + ib_uint64_t* n_not_null; + ibool stats_null_not_equal; + uintmax_t n_sample_pages=1; /* number of pages to sample */ + ulint not_empty_flag = 0; + ulint total_external_size = 0; + ulint i; + ulint j; + uintmax_t add_on; + mtr_t mtr; + mem_heap_t* heap = NULL; + rec_offs* offsets_rec = NULL; + rec_offs* offsets_next_rec = NULL; + + std::vector<index_field_stats_t> result; + + /* For spatial index, there is no such stats can be + fetched. */ + ut_ad(!dict_index_is_spatial(index)); + + n_cols = dict_index_get_n_unique(index); + + heap = mem_heap_create((sizeof *n_diff + sizeof *n_not_null) + * n_cols + + dict_index_get_n_fields(index) + * (sizeof *offsets_rec + + sizeof *offsets_next_rec)); + + n_diff = (ib_uint64_t*) mem_heap_zalloc( + heap, n_cols * sizeof(n_diff[0])); + + n_not_null = NULL; + + /* Check srv_innodb_stats_method setting, and decide whether we + need to record non-null value and also decide if NULL is + considered equal (by setting stats_null_not_equal value) */ + switch (srv_innodb_stats_method) { + case SRV_STATS_NULLS_IGNORED: + n_not_null = (ib_uint64_t*) mem_heap_zalloc( + heap, n_cols * sizeof *n_not_null); + /* fall through */ + + case SRV_STATS_NULLS_UNEQUAL: + /* for both SRV_STATS_NULLS_IGNORED and SRV_STATS_NULLS_UNEQUAL + case, we will treat NULLs as unequal value */ + stats_null_not_equal = TRUE; + break; + + case SRV_STATS_NULLS_EQUAL: + stats_null_not_equal = FALSE; + break; + + default: + ut_error; + } + + if (srv_stats_sample_traditional) { + /* It makes no sense to test more pages than are contained + in the index, thus we lower the number if it is too high */ + if (srv_stats_transient_sample_pages > index->stat_index_size) { + if (index->stat_index_size > 0) { + n_sample_pages = index->stat_index_size; + } + } else { + n_sample_pages = srv_stats_transient_sample_pages; + } + } else { + /* New logaritmic number of pages that are estimated. + Number of pages estimated should be between 1 and + index->stat_index_size. + + If we have only 0 or 1 index pages then we can only take 1 + sample. We have already initialized n_sample_pages to 1. + + So taking index size as I and sample as S and log(I)*S as L + + requirement 1) we want the out limit of the expression to not exceed I; + requirement 2) we want the ideal pages to be at least S; + so the current expression is min(I, max( min(S,I), L) + + looking for simplifications: + + case 1: assume S < I + min(I, max( min(S,I), L) -> min(I , max( S, L)) + + but since L=LOG2(I)*S and log2(I) >=1 L>S always so max(S,L) = L. + + so we have: min(I , L) + + case 2: assume I < S + min(I, max( min(S,I), L) -> min(I, max( I, L)) + + case 2a: L > I + min(I, max( I, L)) -> min(I, L) -> I + + case 2b: when L < I + min(I, max( I, L)) -> min(I, I ) -> I + + so taking all case2 paths is I, our expression is: + n_pages = S < I? min(I,L) : I + */ + if (index->stat_index_size > 1) { + n_sample_pages = (srv_stats_transient_sample_pages < index->stat_index_size) + ? ut_min(index->stat_index_size, + static_cast<ulint>( + log2(double(index->stat_index_size)) + * double(srv_stats_transient_sample_pages))) + : index->stat_index_size; + } + } + + /* Sanity check */ + ut_ad(n_sample_pages > 0 && n_sample_pages <= (index->stat_index_size <= 1 ? 1 : index->stat_index_size)); + + /* We sample some pages in the index to get an estimate */ + + for (i = 0; i < n_sample_pages; i++) { + mtr_start(&mtr); + + bool available; + + available = btr_cur_open_at_rnd_pos(index, BTR_SEARCH_LEAF, + &cursor, &mtr); + + if (!available) { + mtr_commit(&mtr); + mem_heap_free(heap); + + return result; + } + + /* Count the number of different key values for each prefix of + the key on this index page. If the prefix does not determine + the index record uniquely in the B-tree, then we subtract one + because otherwise our algorithm would give a wrong estimate + for an index where there is just one key value. */ + + if (!index->is_readable()) { + mtr_commit(&mtr); + goto exit_loop; + } + + page = btr_cur_get_page(&cursor); + + rec = page_rec_get_next(page_get_infimum_rec(page)); + const ulint n_core = page_is_leaf(page) + ? index->n_core_fields : 0; + + if (!page_rec_is_supremum(rec)) { + not_empty_flag = 1; + offsets_rec = rec_get_offsets(rec, index, offsets_rec, + n_core, + ULINT_UNDEFINED, &heap); + + if (n_not_null != NULL) { + btr_record_not_null_field_in_rec( + n_cols, offsets_rec, n_not_null); + } + } + + while (!page_rec_is_supremum(rec)) { + ulint matched_fields; + rec_t* next_rec = page_rec_get_next(rec); + if (page_rec_is_supremum(next_rec)) { + total_external_size += + btr_rec_get_externally_stored_len( + rec, offsets_rec); + break; + } + + offsets_next_rec = rec_get_offsets(next_rec, index, + offsets_next_rec, + n_core, + ULINT_UNDEFINED, + &heap); + + cmp_rec_rec(rec, next_rec, + offsets_rec, offsets_next_rec, + index, stats_null_not_equal, + &matched_fields); + + for (j = matched_fields; j < n_cols; j++) { + /* We add one if this index record has + a different prefix from the previous */ + + n_diff[j]++; + } + + if (n_not_null != NULL) { + btr_record_not_null_field_in_rec( + n_cols, offsets_next_rec, n_not_null); + } + + total_external_size + += btr_rec_get_externally_stored_len( + rec, offsets_rec); + + rec = next_rec; + /* Initialize offsets_rec for the next round + and assign the old offsets_rec buffer to + offsets_next_rec. */ + { + rec_offs* offsets_tmp = offsets_rec; + offsets_rec = offsets_next_rec; + offsets_next_rec = offsets_tmp; + } + } + + if (n_cols == dict_index_get_n_unique_in_tree(index) + && page_has_siblings(page)) { + + /* If there is more than one leaf page in the tree, + we add one because we know that the first record + on the page certainly had a different prefix than the + last record on the previous index page in the + alphabetical order. Before this fix, if there was + just one big record on each clustered index page, the + algorithm grossly underestimated the number of rows + in the table. */ + + n_diff[n_cols - 1]++; + } + + mtr_commit(&mtr); + } + +exit_loop: + /* If we saw k borders between different key values on + n_sample_pages leaf pages, we can estimate how many + there will be in index->stat_n_leaf_pages */ + + /* We must take into account that our sample actually represents + also the pages used for external storage of fields (those pages are + included in index->stat_n_leaf_pages) */ + + result.reserve(n_cols); + + for (j = 0; j < n_cols; j++) { + index_field_stats_t stat; + + stat.n_diff_key_vals + = BTR_TABLE_STATS_FROM_SAMPLE( + n_diff[j], index, n_sample_pages, + total_external_size, not_empty_flag); + + /* If the tree is small, smaller than + 10 * n_sample_pages + total_external_size, then + the above estimate is ok. For bigger trees it is common that we + do not see any borders between key values in the few pages + we pick. But still there may be n_sample_pages + different key values, or even more. Let us try to approximate + that: */ + + add_on = index->stat_n_leaf_pages + / (10 * (n_sample_pages + + total_external_size)); + + if (add_on > n_sample_pages) { + add_on = n_sample_pages; + } + + stat.n_diff_key_vals += add_on; + + stat.n_sample_sizes = n_sample_pages; + + if (n_not_null != NULL) { + stat.n_non_null_key_vals = + BTR_TABLE_STATS_FROM_SAMPLE( + n_not_null[j], index, n_sample_pages, + total_external_size, not_empty_flag); + } + + result.push_back(stat); + } + + mem_heap_free(heap); + + return result; +} + +/*================== EXTERNAL STORAGE OF BIG FIELDS ===================*/ + +/***********************************************************//** +Gets the offset of the pointer to the externally stored part of a field. +@return offset of the pointer to the externally stored part */ +static +ulint +btr_rec_get_field_ref_offs( +/*=======================*/ + const rec_offs* offsets,/*!< in: array returned by rec_get_offsets() */ + ulint n) /*!< in: index of the external field */ +{ + ulint field_ref_offs; + ulint local_len; + + ut_a(rec_offs_nth_extern(offsets, n)); + field_ref_offs = rec_get_nth_field_offs(offsets, n, &local_len); + ut_a(len_is_stored(local_len)); + ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE); + + return(field_ref_offs + local_len - BTR_EXTERN_FIELD_REF_SIZE); +} + +/** Gets a pointer to the externally stored part of a field. +@param rec record +@param offsets rec_get_offsets(rec) +@param n index of the externally stored field +@return pointer to the externally stored part */ +#define btr_rec_get_field_ref(rec, offsets, n) \ + ((rec) + btr_rec_get_field_ref_offs(offsets, n)) + +/** Gets the externally stored size of a record, in units of a database page. +@param[in] rec record +@param[in] offsets array returned by rec_get_offsets() +@return externally stored part, in units of a database page */ +ulint +btr_rec_get_externally_stored_len( + const rec_t* rec, + const rec_offs* offsets) +{ + ulint n_fields; + ulint total_extern_len = 0; + ulint i; + + ut_ad(!rec_offs_comp(offsets) || !rec_get_node_ptr_flag(rec)); + + if (!rec_offs_any_extern(offsets)) { + return(0); + } + + n_fields = rec_offs_n_fields(offsets); + + for (i = 0; i < n_fields; i++) { + if (rec_offs_nth_extern(offsets, i)) { + + ulint extern_len = mach_read_from_4( + btr_rec_get_field_ref(rec, offsets, i) + + BTR_EXTERN_LEN + 4); + + total_extern_len += ut_calc_align( + extern_len, ulint(srv_page_size)); + } + } + + return total_extern_len >> srv_page_size_shift; +} + +/*******************************************************************//** +Sets the ownership bit of an externally stored field in a record. */ +static +void +btr_cur_set_ownership_of_extern_field( +/*==================================*/ + buf_block_t* block, /*!< in/out: index page */ + rec_t* rec, /*!< in/out: clustered index record */ + dict_index_t* index, /*!< in: index of the page */ + const rec_offs* offsets,/*!< in: array returned by rec_get_offsets() */ + ulint i, /*!< in: field number */ + bool val, /*!< in: value to set */ + mtr_t* mtr) /*!< in: mtr, or NULL if not logged */ +{ + byte* data; + ulint local_len; + ulint byte_val; + + data = rec_get_nth_field(rec, offsets, i, &local_len); + ut_ad(rec_offs_nth_extern(offsets, i)); + ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE); + + local_len -= BTR_EXTERN_FIELD_REF_SIZE; + + byte_val = mach_read_from_1(data + local_len + BTR_EXTERN_LEN); + + if (val) { + byte_val &= ~BTR_EXTERN_OWNER_FLAG; + } else { +#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG + ut_a(!(byte_val & BTR_EXTERN_OWNER_FLAG)); +#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */ + byte_val |= BTR_EXTERN_OWNER_FLAG; + } + + if (UNIV_LIKELY_NULL(block->page.zip.data)) { + mach_write_to_1(data + local_len + BTR_EXTERN_LEN, byte_val); + page_zip_write_blob_ptr(block, rec, index, offsets, i, mtr); + } else { + mtr->write<1,mtr_t::MAYBE_NOP>(*block, data + local_len + + BTR_EXTERN_LEN, byte_val); + } +} + +/*******************************************************************//** +Marks non-updated off-page fields as disowned by this record. The ownership +must be transferred to the updated record which is inserted elsewhere in the +index tree. In purge only the owner of externally stored field is allowed +to free the field. */ +void +btr_cur_disown_inherited_fields( +/*============================*/ + buf_block_t* block, /*!< in/out: index page */ + rec_t* rec, /*!< in/out: record in a clustered index */ + dict_index_t* index, /*!< in: index of the page */ + const rec_offs* offsets,/*!< in: array returned by rec_get_offsets() */ + const upd_t* update, /*!< in: update vector */ + mtr_t* mtr) /*!< in/out: mini-transaction */ +{ + ut_ad(rec_offs_validate(rec, index, offsets)); + ut_ad(!rec_offs_comp(offsets) || !rec_get_node_ptr_flag(rec)); + ut_ad(rec_offs_any_extern(offsets)); + + for (uint16_t i = 0; i < rec_offs_n_fields(offsets); i++) { + if (rec_offs_nth_extern(offsets, i) + && !upd_get_field_by_field_no(update, i, false)) { + btr_cur_set_ownership_of_extern_field( + block, rec, index, offsets, i, false, mtr); + } + } +} + +/*******************************************************************//** +Marks all extern fields in a record as owned by the record. This function +should be called if the delete mark of a record is removed: a not delete +marked record always owns all its extern fields. */ +static +void +btr_cur_unmark_extern_fields( +/*=========================*/ + buf_block_t* block, /*!< in/out: index page */ + rec_t* rec, /*!< in/out: record in a clustered index */ + dict_index_t* index, /*!< in: index of the page */ + const rec_offs* offsets,/*!< in: array returned by rec_get_offsets() */ + mtr_t* mtr) /*!< in: mtr, or NULL if not logged */ +{ + ut_ad(!rec_offs_comp(offsets) || !rec_get_node_ptr_flag(rec)); + if (!rec_offs_any_extern(offsets)) { + return; + } + + const ulint n = rec_offs_n_fields(offsets); + + for (ulint i = 0; i < n; i++) { + if (rec_offs_nth_extern(offsets, i)) { + btr_cur_set_ownership_of_extern_field( + block, rec, index, offsets, i, true, mtr); + } + } +} + +/*******************************************************************//** +Returns the length of a BLOB part stored on the header page. +@return part length */ +static +uint32_t +btr_blob_get_part_len( +/*==================*/ + const byte* blob_header) /*!< in: blob header */ +{ + return(mach_read_from_4(blob_header + BTR_BLOB_HDR_PART_LEN)); +} + +/*******************************************************************//** +Returns the page number where the next BLOB part is stored. +@return page number or FIL_NULL if no more pages */ +static +uint32_t +btr_blob_get_next_page_no( +/*======================*/ + const byte* blob_header) /*!< in: blob header */ +{ + return(mach_read_from_4(blob_header + BTR_BLOB_HDR_NEXT_PAGE_NO)); +} + +/** Deallocate a buffer block that was reserved for a BLOB part. +@param block buffer block +@param all flag whether to remove a ROW_FORMAT=COMPRESSED page +@param mtr mini-transaction to commit */ +static void btr_blob_free(buf_block_t *block, bool all, mtr_t *mtr) +{ + const page_id_t page_id(block->page.id()); + ut_ad(mtr->memo_contains_flagged(block, MTR_MEMO_PAGE_X_FIX)); + mtr->commit(); + + const ulint fold= page_id.fold(); + + mysql_mutex_lock(&buf_pool.mutex); + + if (buf_page_t *bpage= buf_pool.page_hash_get_low(page_id, fold)) + if (!buf_LRU_free_page(bpage, all) && all && bpage->zip.data) + /* Attempt to deallocate the redundant copy of the uncompressed page + if the whole ROW_FORMAT=COMPRESSED block cannot be deallocted. */ + buf_LRU_free_page(bpage, false); + + mysql_mutex_unlock(&buf_pool.mutex); +} + +/** Helper class used while writing blob pages, during insert or update. */ +struct btr_blob_log_check_t { + /** Persistent cursor on a clusterex index record with blobs. */ + btr_pcur_t* m_pcur; + /** Mini transaction holding the latches for m_pcur */ + mtr_t* m_mtr; + /** rec_get_offsets(rec, index); offset of clust_rec */ + const rec_offs* m_offsets; + /** The block containing clustered record */ + buf_block_t** m_block; + /** The clustered record pointer */ + rec_t** m_rec; + /** The blob operation code */ + enum blob_op m_op; + + /** Constructor + @param[in] pcur persistent cursor on a clustered + index record with blobs. + @param[in] mtr mini-transaction holding latches for + pcur. + @param[in] offsets offsets of the clust_rec + @param[in,out] block record block containing pcur record + @param[in,out] rec the clustered record pointer + @param[in] op the blob operation code */ + btr_blob_log_check_t( + btr_pcur_t* pcur, + mtr_t* mtr, + const rec_offs* offsets, + buf_block_t** block, + rec_t** rec, + enum blob_op op) + : m_pcur(pcur), + m_mtr(mtr), + m_offsets(offsets), + m_block(block), + m_rec(rec), + m_op(op) + { + ut_ad(rec_offs_validate(*m_rec, m_pcur->index(), m_offsets)); + ut_ad((*m_block)->frame == page_align(*m_rec)); + ut_ad(*m_rec == btr_pcur_get_rec(m_pcur)); + } + + /** Check if there is enough space in log file. Commit and re-start the + mini transaction. */ + void check() + { + dict_index_t* index = m_pcur->index(); + ulint offs = 0; + uint32_t page_no = FIL_NULL; + + if (UNIV_UNLIKELY(m_op == BTR_STORE_INSERT_BULK)) { + offs = page_offset(*m_rec); + page_no = (*m_block)->page.id().page_no(); + buf_block_buf_fix_inc(*m_block, __FILE__, __LINE__); + ut_ad(page_no != FIL_NULL); + } else { + btr_pcur_store_position(m_pcur, m_mtr); + } + m_mtr->commit(); + + DEBUG_SYNC_C("blob_write_middle"); + + log_free_check(); + + DEBUG_SYNC_C("blob_write_middle_after_check"); + + const mtr_log_t log_mode = m_mtr->get_log_mode(); + m_mtr->start(); + m_mtr->set_log_mode(log_mode); + index->set_modified(*m_mtr); + + if (UNIV_UNLIKELY(page_no != FIL_NULL)) { + m_pcur->btr_cur.page_cur.block = btr_block_get( + *index, page_no, RW_X_LATCH, false, m_mtr); + m_pcur->btr_cur.page_cur.rec + = m_pcur->btr_cur.page_cur.block->frame + + offs; + + buf_block_buf_fix_dec(m_pcur->btr_cur.page_cur.block); + } else { + ut_ad(m_pcur->rel_pos == BTR_PCUR_ON); + bool ret = btr_pcur_restore_position( + BTR_MODIFY_LEAF | BTR_MODIFY_EXTERNAL, + m_pcur, m_mtr); + + ut_a(ret); + } + + *m_block = btr_pcur_get_block(m_pcur); + *m_rec = btr_pcur_get_rec(m_pcur); + + rec_offs_make_valid(*m_rec, index, true, + const_cast<rec_offs*>(m_offsets)); + + ut_ad(m_mtr->memo_contains_page_flagged( + *m_rec, + MTR_MEMO_PAGE_X_FIX | MTR_MEMO_PAGE_SX_FIX)); + + ut_ad((m_op == BTR_STORE_INSERT_BULK) + == !m_mtr->memo_contains_flagged(&index->lock, + MTR_MEMO_SX_LOCK + | MTR_MEMO_X_LOCK)); + } +}; + +/*******************************************************************//** +Stores the fields in big_rec_vec to the tablespace and puts pointers to +them in rec. The extern flags in rec will have to be set beforehand. +The fields are stored on pages allocated from leaf node +file segment of the index tree. + +TODO: If the allocation extends the tablespace, it will not be redo logged, in +any mini-transaction. Tablespace extension should be redo-logged, so that +recovery will not fail when the big_rec was written to the extended portion of +the file, in case the file was somehow truncated in the crash. + +@return DB_SUCCESS or DB_OUT_OF_FILE_SPACE */ +dberr_t +btr_store_big_rec_extern_fields( +/*============================*/ + btr_pcur_t* pcur, /*!< in/out: a persistent cursor. if + btr_mtr is restarted, then this can + be repositioned. */ + rec_offs* offsets, /*!< in/out: rec_get_offsets() on + pcur. the "external storage" flags + in offsets will correctly correspond + to rec when this function returns */ + const big_rec_t*big_rec_vec, /*!< in: vector containing fields + to be stored externally */ + mtr_t* btr_mtr, /*!< in/out: mtr containing the + latches to the clustered index. can be + committed and restarted. */ + enum blob_op op) /*! in: operation code */ +{ + byte* field_ref; + ulint extern_len; + ulint store_len; + ulint space_id; + ulint i; + mtr_t mtr; + mem_heap_t* heap = NULL; + page_zip_des_t* page_zip; + z_stream c_stream; + dberr_t error = DB_SUCCESS; + dict_index_t* index = pcur->index(); + buf_block_t* rec_block = btr_pcur_get_block(pcur); + rec_t* rec = btr_pcur_get_rec(pcur); + + ut_ad(rec_offs_validate(rec, index, offsets)); + ut_ad(rec_offs_any_extern(offsets)); + ut_ad(op == BTR_STORE_INSERT_BULK + || btr_mtr->memo_contains_flagged(&index->lock, MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + ut_ad(btr_mtr->memo_contains_flagged(rec_block, MTR_MEMO_PAGE_X_FIX)); + ut_ad(buf_block_get_frame(rec_block) == page_align(rec)); + ut_a(dict_index_is_clust(index)); + + btr_blob_log_check_t redo_log(pcur, btr_mtr, offsets, &rec_block, + &rec, op); + page_zip = buf_block_get_page_zip(rec_block); + space_id = rec_block->page.id().space(); + ut_a(fil_page_index_page_check(page_align(rec)) + || op == BTR_STORE_INSERT_BULK); + + if (page_zip) { + int err; + + /* Zlib deflate needs 128 kilobytes for the default + window size, plus 512 << memLevel, plus a few + kilobytes for small objects. We use reduced memLevel + to limit the memory consumption, and preallocate the + heap, hoping to avoid memory fragmentation. */ + heap = mem_heap_create(250000); + page_zip_set_alloc(&c_stream, heap); + + err = deflateInit2(&c_stream, int(page_zip_level), + Z_DEFLATED, 15, 7, Z_DEFAULT_STRATEGY); + ut_a(err == Z_OK); + } + +#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG + /* All pointers to externally stored columns in the record + must either be zero or they must be pointers to inherited + columns, owned by this record or an earlier record version. */ + for (i = 0; i < big_rec_vec->n_fields; i++) { + field_ref = btr_rec_get_field_ref( + rec, offsets, big_rec_vec->fields[i].field_no); + + ut_a(!(field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_OWNER_FLAG)); + /* Either this must be an update in place, + or the BLOB must be inherited, or the BLOB pointer + must be zero (will be written in this function). */ + ut_a(op == BTR_STORE_UPDATE + || (field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_INHERITED_FLAG) + || !memcmp(field_ref, field_ref_zero, + BTR_EXTERN_FIELD_REF_SIZE)); + } +#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */ + + /* Space available in compressed page to carry blob data */ + const ulint payload_size_zip = rec_block->physical_size() + - FIL_PAGE_DATA; + + /* Space available in uncompressed page to carry blob data */ + const ulint payload_size = payload_size_zip + - (BTR_BLOB_HDR_SIZE + FIL_PAGE_DATA_END); + + /* We have to create a file segment to the tablespace + for each field and put the pointer to the field in rec */ + + for (i = 0; i < big_rec_vec->n_fields; i++) { + const ulint field_no = big_rec_vec->fields[i].field_no; + + field_ref = btr_rec_get_field_ref(rec, offsets, field_no); +#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG + /* A zero BLOB pointer should have been initially inserted. */ + ut_a(!memcmp(field_ref, field_ref_zero, + BTR_EXTERN_FIELD_REF_SIZE)); +#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */ + extern_len = big_rec_vec->fields[i].len; + MEM_CHECK_DEFINED(big_rec_vec->fields[i].data, extern_len); + ut_a(extern_len > 0); + + uint32_t prev_page_no = FIL_NULL; + + if (page_zip) { + int err = deflateReset(&c_stream); + ut_a(err == Z_OK); + + c_stream.next_in = (Bytef*) + big_rec_vec->fields[i].data; + c_stream.avail_in = static_cast<uInt>(extern_len); + } + + for (ulint blob_npages = 0;; ++blob_npages) { + buf_block_t* block; + const ulint commit_freq = 4; + uint32_t r_extents; + + ut_ad(page_align(field_ref) == page_align(rec)); + + if (!(blob_npages % commit_freq)) { + + redo_log.check(); + + field_ref = btr_rec_get_field_ref( + rec, offsets, field_no); + + page_zip = buf_block_get_page_zip(rec_block); + } + + mtr.start(); + index->set_modified(mtr); + mtr.set_log_mode(btr_mtr->get_log_mode()); + + buf_page_get(rec_block->page.id(), + rec_block->zip_size(), RW_X_LATCH, &mtr); + + uint32_t hint_prev = prev_page_no; + if (hint_prev == FIL_NULL) { + hint_prev = rec_block->page.id().page_no(); + } + + if (!fsp_reserve_free_extents(&r_extents, + index->table->space, 1, + FSP_BLOB, &mtr, 1)) { + mtr.commit(); + error = DB_OUT_OF_FILE_SPACE; + goto func_exit; + } + + block = btr_page_alloc(index, hint_prev + 1, + FSP_NO_DIR, 0, &mtr, &mtr); + + index->table->space->release_free_extents(r_extents); + + ut_a(block != NULL); + + const uint32_t page_no = block->page.id().page_no(); + + if (prev_page_no != FIL_NULL) { + buf_block_t* prev_block; + + prev_block = buf_page_get( + page_id_t(space_id, prev_page_no), + rec_block->zip_size(), + RW_X_LATCH, &mtr); + + buf_block_dbg_add_level(prev_block, + SYNC_EXTERN_STORAGE); + + if (page_zip) { + mtr.write<4>(*prev_block, + prev_block->frame + + FIL_PAGE_NEXT, + page_no); + memcpy_aligned<4>( + buf_block_get_page_zip( + prev_block) + ->data + FIL_PAGE_NEXT, + prev_block->frame + + FIL_PAGE_NEXT, 4); + } else { + mtr.write<4>(*prev_block, + BTR_BLOB_HDR_NEXT_PAGE_NO + + FIL_PAGE_DATA + + prev_block->frame, + page_no); + } + } else if (dict_index_is_online_ddl(index)) { + row_log_table_blob_alloc(index, page_no); + } + + ut_ad(!page_has_siblings(block->frame)); + ut_ad(!fil_page_get_type(block->frame)); + + if (page_zip) { + int err; + page_zip_des_t* blob_page_zip; + + mtr.write<1>(*block, + FIL_PAGE_TYPE + 1 + block->frame, + prev_page_no == FIL_NULL + ? FIL_PAGE_TYPE_ZBLOB + : FIL_PAGE_TYPE_ZBLOB2); + block->page.zip.data[FIL_PAGE_TYPE + 1] + = block->frame[FIL_PAGE_TYPE + 1]; + + c_stream.next_out = block->frame + + FIL_PAGE_DATA; + c_stream.avail_out = static_cast<uInt>( + payload_size_zip); + + err = deflate(&c_stream, Z_FINISH); + ut_a(err == Z_OK || err == Z_STREAM_END); + ut_a(err == Z_STREAM_END + || c_stream.avail_out == 0); + + mtr.memcpy(*block, + FIL_PAGE_DATA, + page_zip_get_size(page_zip) + - FIL_PAGE_DATA + - c_stream.avail_out); + /* Copy the page to compressed storage, + because it will be flushed to disk + from there. */ + blob_page_zip = buf_block_get_page_zip(block); + ut_ad(blob_page_zip); + ut_ad(page_zip_get_size(blob_page_zip) + == page_zip_get_size(page_zip)); + memcpy(blob_page_zip->data, block->frame, + page_zip_get_size(page_zip)); + + if (err == Z_OK && prev_page_no != FIL_NULL) { + + goto next_zip_page; + } + + if (err == Z_STREAM_END) { + mach_write_to_4(field_ref + + BTR_EXTERN_LEN, 0); + mach_write_to_4(field_ref + + BTR_EXTERN_LEN + 4, + c_stream.total_in); + } else { + memset(field_ref + BTR_EXTERN_LEN, + 0, 8); + } + + if (prev_page_no == FIL_NULL) { + ut_ad(blob_npages == 0); + mach_write_to_4(field_ref + + BTR_EXTERN_SPACE_ID, + space_id); + + mach_write_to_4(field_ref + + BTR_EXTERN_PAGE_NO, + page_no); + + mach_write_to_4(field_ref + + BTR_EXTERN_OFFSET, + FIL_PAGE_NEXT); + } + + /* We compress a page when finish bulk insert.*/ + if (UNIV_LIKELY(op != BTR_STORE_INSERT_BULK)) { + page_zip_write_blob_ptr( + rec_block, rec, index, offsets, + field_no, &mtr); + } + +next_zip_page: + prev_page_no = page_no; + + /* Commit mtr and release the + uncompressed page frame to save memory. */ + btr_blob_free(block, FALSE, &mtr); + + if (err == Z_STREAM_END) { + break; + } + } else { + mtr.write<1>(*block, FIL_PAGE_TYPE + 1 + + block->frame, + FIL_PAGE_TYPE_BLOB); + + if (extern_len > payload_size) { + store_len = payload_size; + } else { + store_len = extern_len; + } + + mtr.memcpy<mtr_t::MAYBE_NOP>( + *block, + FIL_PAGE_DATA + BTR_BLOB_HDR_SIZE + + block->frame, + static_cast<const byte*> + (big_rec_vec->fields[i].data) + + big_rec_vec->fields[i].len + - extern_len, store_len); + mtr.write<4>(*block, BTR_BLOB_HDR_PART_LEN + + FIL_PAGE_DATA + block->frame, + store_len); + compile_time_assert(FIL_NULL == 0xffffffff); + mtr.memset(block, BTR_BLOB_HDR_NEXT_PAGE_NO + + FIL_PAGE_DATA, 4, 0xff); + + extern_len -= store_len; + + ut_ad(!mach_read_from_4(BTR_EXTERN_LEN + + field_ref)); + mtr.write<4>(*rec_block, + BTR_EXTERN_LEN + 4 + field_ref, + big_rec_vec->fields[i].len + - extern_len); + + if (prev_page_no == FIL_NULL) { + ut_ad(blob_npages == 0); + mtr.write<4,mtr_t::MAYBE_NOP>( + *rec_block, + field_ref + BTR_EXTERN_SPACE_ID, + space_id); + + mtr.write<4>(*rec_block, field_ref + + BTR_EXTERN_PAGE_NO, + page_no); + + mtr.write<4>(*rec_block, field_ref + + BTR_EXTERN_OFFSET, + FIL_PAGE_DATA); + } + + prev_page_no = page_no; + + mtr.commit(); + + if (extern_len == 0) { + break; + } + } + } + + DBUG_EXECUTE_IF("btr_store_big_rec_extern", + error = DB_OUT_OF_FILE_SPACE; + goto func_exit;); + + rec_offs_make_nth_extern(offsets, field_no); + } + +func_exit: + if (page_zip) { + deflateEnd(&c_stream); + } + + if (heap != NULL) { + mem_heap_free(heap); + } + +#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG + /* All pointers to externally stored columns in the record + must be valid. */ + for (i = 0; i < rec_offs_n_fields(offsets); i++) { + if (!rec_offs_nth_extern(offsets, i)) { + continue; + } + + field_ref = btr_rec_get_field_ref(rec, offsets, i); + + /* The pointer must not be zero if the operation + succeeded. */ + ut_a(0 != memcmp(field_ref, field_ref_zero, + BTR_EXTERN_FIELD_REF_SIZE) + || error != DB_SUCCESS); + /* The column must not be disowned by this record. */ + ut_a(!(field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_OWNER_FLAG)); + } +#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */ + return(error); +} + +/** Check the FIL_PAGE_TYPE on an uncompressed BLOB page. +@param[in] block uncompressed BLOB page +@param[in] read true=read, false=purge */ +static void btr_check_blob_fil_page_type(const buf_block_t& block, bool read) +{ + uint16_t type= fil_page_get_type(block.frame); + + if (UNIV_LIKELY(type == FIL_PAGE_TYPE_BLOB)) + return; + /* FIXME: take the tablespace as a parameter */ + if (fil_space_t *space= fil_space_t::get(block.page.id().space())) + { + /* Old versions of InnoDB did not initialize FIL_PAGE_TYPE on BLOB + pages. Do not print anything about the type mismatch when reading + a BLOB page that may be from old versions. */ + if (space->full_crc32() || DICT_TF_HAS_ATOMIC_BLOBS(space->flags)) + { + ib::fatal() << "FIL_PAGE_TYPE=" << type + << (read ? " on BLOB read file " : " on BLOB purge file ") + << space->chain.start->name + << " page " << block.page.id().page_no(); + } + space->release(); + } +} + +/*******************************************************************//** +Frees the space in an externally stored field to the file space +management if the field in data is owned by the externally stored field, +in a rollback we may have the additional condition that the field must +not be inherited. */ +void +btr_free_externally_stored_field( +/*=============================*/ + dict_index_t* index, /*!< in: index of the data, the index + tree MUST be X-latched; if the tree + height is 1, then also the root page + must be X-latched! (this is relevant + in the case this function is called + from purge where 'data' is located on + an undo log page, not an index + page) */ + byte* field_ref, /*!< in/out: field reference */ + const rec_t* rec, /*!< in: record containing field_ref, for + page_zip_write_blob_ptr(), or NULL */ + const rec_offs* offsets, /*!< in: rec_get_offsets(rec, index), + or NULL */ + buf_block_t* block, /*!< in/out: page of field_ref */ + ulint i, /*!< in: field number of field_ref; + ignored if rec == NULL */ + bool rollback, /*!< in: performing rollback? */ + mtr_t* local_mtr) /*!< in: mtr + containing the latch to data an an + X-latch to the index tree */ +{ + page_t* page; + const uint32_t space_id = mach_read_from_4( + field_ref + BTR_EXTERN_SPACE_ID); + const uint32_t start_page = mach_read_from_4( + field_ref + BTR_EXTERN_PAGE_NO); + uint32_t page_no; + uint32_t next_page_no; + mtr_t mtr; + + ut_ad(index->is_primary()); + ut_ad(local_mtr->memo_contains_flagged(&index->lock, MTR_MEMO_X_LOCK + | MTR_MEMO_SX_LOCK)); + ut_ad(local_mtr->memo_contains_page_flagged(field_ref, + MTR_MEMO_PAGE_X_FIX)); + ut_ad(!rec || rec_offs_validate(rec, index, offsets)); + ut_ad(!rec || field_ref == btr_rec_get_field_ref(rec, offsets, i)); + ut_ad(local_mtr->is_named_space( + page_get_space_id(page_align(field_ref)))); + + if (UNIV_UNLIKELY(!memcmp(field_ref, field_ref_zero, + BTR_EXTERN_FIELD_REF_SIZE))) { + /* In the rollback, we may encounter a clustered index + record with some unwritten off-page columns. There is + nothing to free then. */ + ut_a(rollback); + return; + } + + ut_ad(!(mach_read_from_4(field_ref + BTR_EXTERN_LEN) + & ~((BTR_EXTERN_OWNER_FLAG + | BTR_EXTERN_INHERITED_FLAG) << 24))); + ut_ad(space_id == index->table->space->id); + ut_ad(space_id == index->table->space_id); + + const ulint ext_zip_size = index->table->space->zip_size(); + const ulint rec_zip_size = rec ? ext_zip_size : 0; + + /* !rec holds in a call from purge when field_ref is in an undo page */ + ut_ad(rec || !block->page.zip.data); + + for (;;) { +#ifdef UNIV_DEBUG + buf_block_t* rec_block; +#endif /* UNIV_DEBUG */ + buf_block_t* ext_block; + + mtr_start(&mtr); + mtr.set_spaces(*local_mtr); + mtr.set_log_mode(local_mtr->get_log_mode()); + + ut_ad(!index->table->is_temporary() + || local_mtr->get_log_mode() == MTR_LOG_NO_REDO); + + const page_t* p = page_align(field_ref); + + const page_id_t page_id(page_get_space_id(p), + page_get_page_no(p)); + +#ifdef UNIV_DEBUG + rec_block = +#endif /* UNIV_DEBUG */ + buf_page_get(page_id, rec_zip_size, RW_X_LATCH, &mtr); + + buf_block_dbg_add_level(rec_block, SYNC_NO_ORDER_CHECK); + page_no = mach_read_from_4(field_ref + BTR_EXTERN_PAGE_NO); + + if (/* There is no external storage data */ + page_no == FIL_NULL + /* This field does not own the externally stored field */ + || (mach_read_from_1(field_ref + BTR_EXTERN_LEN) + & BTR_EXTERN_OWNER_FLAG) + /* Rollback and inherited field */ + || (rollback + && (mach_read_from_1(field_ref + BTR_EXTERN_LEN) + & BTR_EXTERN_INHERITED_FLAG))) { + + /* Do not free */ + mtr_commit(&mtr); + + return; + } + + if (page_no == start_page && dict_index_is_online_ddl(index)) { + row_log_table_blob_free(index, start_page); + } + + ext_block = buf_page_get( + page_id_t(space_id, page_no), ext_zip_size, + RW_X_LATCH, &mtr); + + buf_block_dbg_add_level(ext_block, SYNC_EXTERN_STORAGE); + page = buf_block_get_frame(ext_block); + + if (ext_zip_size) { + /* Note that page_zip will be NULL + in row_purge_upd_exist_or_extern(). */ + switch (fil_page_get_type(page)) { + case FIL_PAGE_TYPE_ZBLOB: + case FIL_PAGE_TYPE_ZBLOB2: + break; + default: + ut_error; + } + next_page_no = mach_read_from_4(page + FIL_PAGE_NEXT); + + btr_page_free(index, ext_block, &mtr, true); + + if (UNIV_LIKELY_NULL(block->page.zip.data)) { + mach_write_to_4(field_ref + BTR_EXTERN_PAGE_NO, + next_page_no); + memset(field_ref + BTR_EXTERN_LEN + 4, 0, 4); + page_zip_write_blob_ptr(block, rec, index, + offsets, i, &mtr); + } else { + mtr.write<4>(*block, + BTR_EXTERN_PAGE_NO + field_ref, + next_page_no); + mtr.write<4,mtr_t::MAYBE_NOP>(*block, + BTR_EXTERN_LEN + + 4 + field_ref, + 0U); + } + } else { + ut_ad(!block->page.zip.data); + btr_check_blob_fil_page_type(*ext_block, false); + + next_page_no = mach_read_from_4( + page + FIL_PAGE_DATA + + BTR_BLOB_HDR_NEXT_PAGE_NO); + btr_page_free(index, ext_block, &mtr, true); + + mtr.write<4>(*block, BTR_EXTERN_PAGE_NO + field_ref, + next_page_no); + /* Zero out the BLOB length. If the server + crashes during the execution of this function, + trx_rollback_all_recovered() could + dereference the half-deleted BLOB, fetching a + wrong prefix for the BLOB. */ + mtr.write<4,mtr_t::MAYBE_NOP>(*block, + BTR_EXTERN_LEN + 4 + + field_ref, 0U); + } + + /* Commit mtr and release the BLOB block to save memory. */ + btr_blob_free(ext_block, TRUE, &mtr); + } +} + +/***********************************************************//** +Frees the externally stored fields for a record. */ +static +void +btr_rec_free_externally_stored_fields( +/*==================================*/ + dict_index_t* index, /*!< in: index of the data, the index + tree MUST be X-latched */ + rec_t* rec, /*!< in/out: record */ + const rec_offs* offsets,/*!< in: rec_get_offsets(rec, index) */ + buf_block_t* block, /*!< in: index page of rec */ + bool rollback,/*!< in: performing rollback? */ + mtr_t* mtr) /*!< in: mini-transaction handle which contains + an X-latch to record page and to the index + tree */ +{ + ulint n_fields; + ulint i; + + ut_ad(rec_offs_validate(rec, index, offsets)); + ut_ad(mtr->memo_contains_page_flagged(rec, MTR_MEMO_PAGE_X_FIX)); + ut_ad(index->is_primary()); + ut_ad(page_rec_is_leaf(rec)); + /* Free possible externally stored fields in the record */ + + ut_ad(dict_table_is_comp(index->table) == !!rec_offs_comp(offsets)); + n_fields = rec_offs_n_fields(offsets); + + for (i = 0; i < n_fields; i++) { + if (rec_offs_nth_extern(offsets, i)) { + btr_free_externally_stored_field( + index, btr_rec_get_field_ref(rec, offsets, i), + rec, offsets, block, i, rollback, mtr); + } + } +} + +/***********************************************************//** +Frees the externally stored fields for a record, if the field is mentioned +in the update vector. */ +static +void +btr_rec_free_updated_extern_fields( +/*===============================*/ + dict_index_t* index, /*!< in: index of rec; the index tree MUST be + X-latched */ + rec_t* rec, /*!< in/out: record */ + buf_block_t* block, /*!< in: index page of rec */ + const rec_offs* offsets,/*!< in: rec_get_offsets(rec, index) */ + const upd_t* update, /*!< in: update vector */ + bool rollback,/*!< in: performing rollback? */ + mtr_t* mtr) /*!< in: mini-transaction handle which contains + an X-latch to record page and to the tree */ +{ + ulint n_fields; + ulint i; + + ut_ad(rec_offs_validate(rec, index, offsets)); + ut_ad(mtr->memo_contains_page_flagged(rec, MTR_MEMO_PAGE_X_FIX)); + + /* Free possible externally stored fields in the record */ + + n_fields = upd_get_n_fields(update); + + for (i = 0; i < n_fields; i++) { + const upd_field_t* ufield = upd_get_nth_field(update, i); + + if (rec_offs_nth_extern(offsets, ufield->field_no)) { + ulint len; + byte* data = rec_get_nth_field( + rec, offsets, ufield->field_no, &len); + ut_a(len >= BTR_EXTERN_FIELD_REF_SIZE); + + btr_free_externally_stored_field( + index, data + len - BTR_EXTERN_FIELD_REF_SIZE, + rec, offsets, block, + ufield->field_no, rollback, mtr); + } + } +} + +/*******************************************************************//** +Copies the prefix of an uncompressed BLOB. The clustered index record +that points to this BLOB must be protected by a lock or a page latch. +@return number of bytes written to buf */ +static +ulint +btr_copy_blob_prefix( +/*=================*/ + byte* buf, /*!< out: the externally stored part of + the field, or a prefix of it */ + uint32_t len, /*!< in: length of buf, in bytes */ + page_id_t id, /*!< in: page identifier of the first BLOB page */ + uint32_t offset) /*!< in: offset on the first BLOB page */ +{ + ulint copied_len = 0; + + for (;;) { + mtr_t mtr; + buf_block_t* block; + const page_t* page; + const byte* blob_header; + ulint part_len; + ulint copy_len; + + mtr_start(&mtr); + + block = buf_page_get(id, 0, RW_S_LATCH, &mtr); + buf_block_dbg_add_level(block, SYNC_EXTERN_STORAGE); + page = buf_block_get_frame(block); + + btr_check_blob_fil_page_type(*block, true); + + blob_header = page + offset; + part_len = btr_blob_get_part_len(blob_header); + copy_len = ut_min(part_len, len - copied_len); + + memcpy(buf + copied_len, + blob_header + BTR_BLOB_HDR_SIZE, copy_len); + copied_len += copy_len; + + id.set_page_no(btr_blob_get_next_page_no(blob_header)); + + mtr_commit(&mtr); + + if (id.page_no() == FIL_NULL || copy_len != part_len) { + MEM_CHECK_DEFINED(buf, copied_len); + return(copied_len); + } + + /* On other BLOB pages except the first the BLOB header + always is at the page data start: */ + + offset = FIL_PAGE_DATA; + + ut_ad(copied_len <= len); + } +} + +/** Copies the prefix of a compressed BLOB. +The clustered index record that points to this BLOB must be protected +by a lock or a page latch. +@param[out] buf the externally stored part of the field, +or a prefix of it +@param[in] len length of buf, in bytes +@param[in] zip_size ROW_FORMAT=COMPRESSED page size +@param[in] id page identifier of the BLOB pages +@return number of bytes written to buf */ +static +ulint +btr_copy_zblob_prefix( + byte* buf, + uint32_t len, + ulint zip_size, + page_id_t id, + uint32_t offset) +{ + ulint page_type = FIL_PAGE_TYPE_ZBLOB; + mem_heap_t* heap; + int err; + z_stream d_stream; + + d_stream.next_out = buf; + d_stream.avail_out = static_cast<uInt>(len); + d_stream.next_in = Z_NULL; + d_stream.avail_in = 0; + + /* Zlib inflate needs 32 kilobytes for the default + window size, plus a few kilobytes for small objects. */ + heap = mem_heap_create(40000); + page_zip_set_alloc(&d_stream, heap); + + ut_ad(zip_size); + ut_ad(ut_is_2pow(zip_size)); + ut_ad(id.space()); + + err = inflateInit(&d_stream); + ut_a(err == Z_OK); + + for (;;) { + buf_page_t* bpage; + uint32_t next_page_no; + + /* There is no latch on bpage directly. Instead, + bpage is protected by the B-tree page latch that + is being held on the clustered index record, or, + in row_merge_copy_blobs(), by an exclusive table lock. */ + bpage = buf_page_get_zip(id, zip_size); + + if (UNIV_UNLIKELY(!bpage)) { + ib::error() << "Cannot load compressed BLOB " << id; + goto func_exit; + } + + if (UNIV_UNLIKELY + (fil_page_get_type(bpage->zip.data) != page_type)) { + + ib::error() << "Unexpected type " + << fil_page_get_type(bpage->zip.data) + << " of compressed BLOB page " << id; + + ut_ad(0); + goto end_of_blob; + } + + next_page_no = mach_read_from_4(bpage->zip.data + offset); + + if (UNIV_LIKELY(offset == FIL_PAGE_NEXT)) { + /* When the BLOB begins at page header, + the compressed data payload does not + immediately follow the next page pointer. */ + offset = FIL_PAGE_DATA; + } else { + offset += 4; + } + + d_stream.next_in = bpage->zip.data + offset; + d_stream.avail_in = uInt(zip_size - offset); + + err = inflate(&d_stream, Z_NO_FLUSH); + switch (err) { + case Z_OK: + if (!d_stream.avail_out) { + goto end_of_blob; + } + break; + case Z_STREAM_END: + if (next_page_no == FIL_NULL) { + goto end_of_blob; + } + /* fall through */ + default: +inflate_error: + ib::error() << "inflate() of compressed BLOB page " + << id + << " returned " << err + << " (" << d_stream.msg << ")"; + + case Z_BUF_ERROR: + goto end_of_blob; + } + + if (next_page_no == FIL_NULL) { + if (!d_stream.avail_in) { + ib::error() + << "Unexpected end of compressed " + << "BLOB page " << id; + } else { + err = inflate(&d_stream, Z_FINISH); + switch (err) { + case Z_STREAM_END: + case Z_BUF_ERROR: + break; + default: + goto inflate_error; + } + } + +end_of_blob: + buf_page_release_zip(bpage); + goto func_exit; + } + + buf_page_release_zip(bpage); + + /* On other BLOB pages except the first + the BLOB header always is at the page header: */ + + id.set_page_no(next_page_no); + offset = FIL_PAGE_NEXT; + page_type = FIL_PAGE_TYPE_ZBLOB2; + } + +func_exit: + inflateEnd(&d_stream); + mem_heap_free(heap); + MEM_CHECK_DEFINED(buf, d_stream.total_out); + return(d_stream.total_out); +} + +/** Copies the prefix of an externally stored field of a record. +The clustered index record that points to this BLOB must be protected +by a lock or a page latch. +@param[out] buf the externally stored part of the +field, or a prefix of it +@param[in] len length of buf, in bytes +@param[in] zip_size ROW_FORMAT=COMPRESSED page size, or 0 +@param[in] id page identifier of the first BLOB page +@param[in] offset offset on the first BLOB page +@return number of bytes written to buf */ +static +ulint +btr_copy_externally_stored_field_prefix_low( + byte* buf, + uint32_t len, + ulint zip_size, + page_id_t id, + uint32_t offset) +{ + if (len == 0) + return 0; + + return zip_size + ? btr_copy_zblob_prefix(buf, len, zip_size, id, offset) + : btr_copy_blob_prefix(buf, len, id, offset); +} + +/** Copies the prefix of an externally stored field of a record. +The clustered index record must be protected by a lock or a page latch. +@param[out] buf the field, or a prefix of it +@param[in] len length of buf, in bytes +@param[in] zip_size ROW_FORMAT=COMPRESSED page size, or 0 +@param[in] data 'internally' stored part of the field +containing also the reference to the external part; must be protected by +a lock or a page latch +@param[in] local_len length of data, in bytes +@return the length of the copied field, or 0 if the column was being +or has been deleted */ +ulint +btr_copy_externally_stored_field_prefix( + byte* buf, + ulint len, + ulint zip_size, + const byte* data, + ulint local_len) +{ + ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE); + + local_len -= BTR_EXTERN_FIELD_REF_SIZE; + + if (UNIV_UNLIKELY(local_len >= len)) { + memcpy(buf, data, len); + return(len); + } + + memcpy(buf, data, local_len); + data += local_len; + + ut_a(memcmp(data, field_ref_zero, BTR_EXTERN_FIELD_REF_SIZE)); + + if (!mach_read_from_4(data + BTR_EXTERN_LEN + 4)) { + /* The externally stored part of the column has been + (partially) deleted. Signal the half-deleted BLOB + to the caller. */ + + return(0); + } + + uint32_t space_id = mach_read_from_4(data + BTR_EXTERN_SPACE_ID); + uint32_t page_no = mach_read_from_4(data + BTR_EXTERN_PAGE_NO); + uint32_t offset = mach_read_from_4(data + BTR_EXTERN_OFFSET); + len -= local_len; + + return(local_len + + btr_copy_externally_stored_field_prefix_low(buf + local_len, + uint32_t(len), + zip_size, + page_id_t( + space_id, + page_no), + offset)); +} + +/** Copies an externally stored field of a record to mem heap. +The clustered index record must be protected by a lock or a page latch. +@param[out] len length of the whole field +@param[in] data 'internally' stored part of the field +containing also the reference to the external part; must be protected by +a lock or a page latch +@param[in] zip_size ROW_FORMAT=COMPRESSED page size, or 0 +@param[in] local_len length of data +@param[in,out] heap mem heap +@return the whole field copied to heap */ +byte* +btr_copy_externally_stored_field( + ulint* len, + const byte* data, + ulint zip_size, + ulint local_len, + mem_heap_t* heap) +{ + byte* buf; + + ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE); + + local_len -= BTR_EXTERN_FIELD_REF_SIZE; + + uint32_t space_id = mach_read_from_4(data + local_len + + BTR_EXTERN_SPACE_ID); + uint32_t page_no = mach_read_from_4(data + local_len + + BTR_EXTERN_PAGE_NO); + uint32_t offset = mach_read_from_4(data + local_len + + BTR_EXTERN_OFFSET); + + /* Currently a BLOB cannot be bigger than 4 GB; we + leave the 4 upper bytes in the length field unused */ + + uint32_t extern_len = mach_read_from_4(data + local_len + + BTR_EXTERN_LEN + 4); + + buf = (byte*) mem_heap_alloc(heap, local_len + extern_len); + + memcpy(buf, data, local_len); + *len = local_len + + btr_copy_externally_stored_field_prefix_low(buf + local_len, + extern_len, + zip_size, + page_id_t( + space_id, + page_no), + offset); + + return(buf); +} + +/** Copies an externally stored field of a record to mem heap. +@param[in] rec record in a clustered index; must be +protected by a lock or a page latch +@param[in] offset array returned by rec_get_offsets() +@param[in] zip_size ROW_FORMAT=COMPRESSED page size, or 0 +@param[in] no field number +@param[out] len length of the field +@param[in,out] heap mem heap +@return the field copied to heap, or NULL if the field is incomplete */ +byte* +btr_rec_copy_externally_stored_field( + const rec_t* rec, + const rec_offs* offsets, + ulint zip_size, + ulint no, + ulint* len, + mem_heap_t* heap) +{ + ulint local_len; + const byte* data; + + ut_a(rec_offs_nth_extern(offsets, no)); + + /* An externally stored field can contain some initial + data from the field, and in the last 20 bytes it has the + space id, page number, and offset where the rest of the + field data is stored, and the data length in addition to + the data stored locally. We may need to store some data + locally to get the local record length above the 128 byte + limit so that field offsets are stored in two bytes, and + the extern bit is available in those two bytes. */ + + data = rec_get_nth_field(rec, offsets, no, &local_len); + + ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE); + + if (UNIV_UNLIKELY + (!memcmp(data + local_len - BTR_EXTERN_FIELD_REF_SIZE, + field_ref_zero, BTR_EXTERN_FIELD_REF_SIZE))) { + /* The externally stored field was not written yet. + This record should only be seen by + trx_rollback_recovered() or any + TRX_ISO_READ_UNCOMMITTED transactions. */ + return(NULL); + } + + return(btr_copy_externally_stored_field(len, data, + zip_size, local_len, heap)); +} |