/****************************************************** 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. (c) 1994-2001 Innobase Oy Created 10/16/1994 Heikki Tuuri *******************************************************/ #include "btr0cur.h" #ifdef UNIV_NONINL #include "btr0cur.ic" #endif #include "page0page.h" #include "page0zip.h" #include "rem0rec.h" #include "rem0cmp.h" #include "buf0lru.h" #include "btr0btr.h" #include "btr0sea.h" #include "row0upd.h" #include "trx0rec.h" #include "trx0roll.h" /* trx_is_recv() */ #include "que0que.h" #include "row0row.h" #include "srv0srv.h" #include "ibuf0ibuf.h" #include "lock0lock.h" #include "zlib.h" #ifdef UNIV_DEBUG /* If the following is set to TRUE, this module prints a lot of trace information of individual record operations */ UNIV_INTERN ibool btr_cur_print_record_ops = FALSE; #endif /* UNIV_DEBUG */ UNIV_INTERN ulint btr_cur_n_non_sea = 0; UNIV_INTERN ulint btr_cur_n_sea = 0; UNIV_INTERN ulint btr_cur_n_non_sea_old = 0; UNIV_INTERN ulint btr_cur_n_sea_old = 0; /* 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 (UNIV_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 /* A BLOB field reference full of zero, for use in assertions and tests. Initially, BLOB field references are set to zero, in dtuple_convert_big_rec(). */ UNIV_INTERN const byte field_ref_zero[BTR_EXTERN_FIELD_REF_SIZE]= {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; /*********************************************************************** 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( /*=========================*/ page_zip_des_t* page_zip,/* in/out: compressed page whose uncompressed part will be updated, or NULL */ rec_t* rec, /* in/out: record in a clustered index */ dict_index_t* index, /* in: index of the page */ const ulint* 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 */ page_zip_des_t* page_zip,/* in: compressed page whose uncompressed part will be updated, or NULL */ const ulint* offsets,/* in: rec_get_offsets(rec, index) */ const upd_t* update, /* in: update vector */ enum trx_rb_ctx rb_ctx, /* in: rollback context */ 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 ulint* offsets,/* in: rec_get_offsets(rec, index) */ page_zip_des_t* page_zip,/* in: compressed page whose uncompressed part will be updated, or NULL */ enum trx_rb_ctx rb_ctx, /* in: rollback context */ mtr_t* mtr); /* in: mini-transaction handle which contains an X-latch to record page and to the index tree */ /*************************************************************** Gets the externally stored size of a record, in units of a database page. */ static ulint btr_rec_get_externally_stored_len( /*==============================*/ /* out: externally stored part, in units of a database page */ rec_t* rec, /* in: record */ const ulint* offsets);/* in: array returned by rec_get_offsets() */ /********************************************************** The following function is used to set the deleted bit of a record. */ UNIV_INLINE void btr_rec_set_deleted_flag( /*=====================*/ /* out: TRUE on success; FALSE on page_zip overflow */ rec_t* rec, /* in/out: physical record */ page_zip_des_t* page_zip,/* in/out: compressed page (or NULL) */ ulint flag) /* in: nonzero if delete marked */ { if (page_rec_is_comp(rec)) { rec_set_deleted_flag_new(rec, page_zip, flag); } else { ut_ad(!page_zip); rec_set_deleted_flag_old(rec, flag); } } /*==================== B-TREE SEARCH =========================*/ /************************************************************************ Latches the leaf page or pages requested. */ static void btr_cur_latch_leaves( /*=================*/ page_t* page, /* in: leaf page where the search converged */ ulint space, /* in: space id */ ulint zip_size, /* in: compressed page size in bytes or 0 for uncompressed pages */ ulint page_no, /* in: page number of the leaf */ ulint latch_mode, /* in: BTR_SEARCH_LEAF, ... */ btr_cur_t* cursor, /* in: cursor */ mtr_t* mtr) /* in: mtr */ { ulint mode; ulint left_page_no; ulint right_page_no; buf_block_t* get_block; ut_ad(page && mtr); switch (latch_mode) { case BTR_SEARCH_LEAF: case BTR_MODIFY_LEAF: mode = latch_mode == BTR_SEARCH_LEAF ? RW_S_LATCH : RW_X_LATCH; get_block = btr_block_get(space, zip_size, page_no, mode, mtr); #ifdef UNIV_BTR_DEBUG ut_a(page_is_comp(get_block->frame) == page_is_comp(page)); #endif /* UNIV_BTR_DEBUG */ get_block->check_index_page_at_flush = TRUE; return; case BTR_MODIFY_TREE: /* x-latch also brothers from left to right */ left_page_no = btr_page_get_prev(page, mtr); if (left_page_no != FIL_NULL) { get_block = btr_block_get(space, zip_size, left_page_no, RW_X_LATCH, mtr); #ifdef UNIV_BTR_DEBUG ut_a(page_is_comp(get_block->frame) == page_is_comp(page)); ut_a(btr_page_get_next(get_block->frame, mtr) == page_get_page_no(page)); #endif /* UNIV_BTR_DEBUG */ get_block->check_index_page_at_flush = TRUE; } get_block = btr_block_get(space, zip_size, page_no, RW_X_LATCH, mtr); #ifdef UNIV_BTR_DEBUG ut_a(page_is_comp(get_block->frame) == page_is_comp(page)); #endif /* UNIV_BTR_DEBUG */ get_block->check_index_page_at_flush = TRUE; right_page_no = btr_page_get_next(page, mtr); if (right_page_no != FIL_NULL) { get_block = btr_block_get(space, zip_size, right_page_no, RW_X_LATCH, mtr); #ifdef UNIV_BTR_DEBUG ut_a(page_is_comp(get_block->frame) == page_is_comp(page)); ut_a(btr_page_get_prev(get_block->frame, mtr) == page_get_page_no(page)); #endif /* UNIV_BTR_DEBUG */ get_block->check_index_page_at_flush = TRUE; } return; case BTR_SEARCH_PREV: case BTR_MODIFY_PREV: mode = latch_mode == BTR_SEARCH_PREV ? RW_S_LATCH : RW_X_LATCH; /* latch also left brother */ left_page_no = btr_page_get_prev(page, mtr); if (left_page_no != FIL_NULL) { get_block = btr_block_get(space, zip_size, left_page_no, mode, mtr); cursor->left_block = get_block; #ifdef UNIV_BTR_DEBUG ut_a(page_is_comp(get_block->frame) == page_is_comp(page)); ut_a(btr_page_get_next(get_block->frame, mtr) == page_get_page_no(page)); #endif /* UNIV_BTR_DEBUG */ get_block->check_index_page_at_flush = TRUE; } get_block = btr_block_get(space, zip_size, page_no, mode, mtr); #ifdef UNIV_BTR_DEBUG ut_a(page_is_comp(get_block->frame) == page_is_comp(page)); #endif /* UNIV_BTR_DEBUG */ get_block->check_index_page_at_flush = TRUE; return; } ut_error; } /************************************************************************ 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. */ UNIV_INTERN void btr_cur_search_to_nth_level( /*========================*/ 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! */ ulint 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 BTR_INSERT and 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 has_search_latch is != 0, we maybe do not have a latch set on the cursor page, we assume the caller uses his search latch to protect the record! */ btr_cur_t* cursor, /* in/out: tree cursor; the cursor page is s- or x-latched, but see also above! */ ulint has_search_latch,/* in: info on the latch mode the caller currently has on btr_search_latch: RW_S_LATCH, or 0 */ mtr_t* mtr) /* in: mtr */ { page_cur_t* page_cursor; page_t* page; buf_block_t* guess; rec_t* node_ptr; ulint page_no; ulint space; ulint up_match; ulint up_bytes; ulint low_match; ulint low_bytes; ulint height; ulint savepoint; ulint rw_latch; ulint page_mode; ulint insert_planned; ulint buf_mode; ulint estimate; ulint ignore_sec_unique; ulint root_height = 0; /* remove warning */ #ifdef BTR_CUR_ADAPT btr_search_t* info; #endif mem_heap_t* heap = NULL; ulint offsets_[REC_OFFS_NORMAL_SIZE]; ulint* offsets = offsets_; rec_offs_init(offsets_); /* Currently, PAGE_CUR_LE is the only search mode used for searches ending to upper levels */ ut_ad(level == 0 || mode == PAGE_CUR_LE); ut_ad(dict_index_check_search_tuple(index, tuple)); ut_ad(!dict_index_is_ibuf(index) || ibuf_inside()); ut_ad(dtuple_check_typed(tuple)); #ifdef UNIV_DEBUG cursor->up_match = ULINT_UNDEFINED; cursor->low_match = ULINT_UNDEFINED; #endif insert_planned = latch_mode & BTR_INSERT; estimate = latch_mode & BTR_ESTIMATE; ignore_sec_unique = latch_mode & BTR_IGNORE_SEC_UNIQUE; latch_mode = latch_mode & ~(BTR_INSERT | BTR_ESTIMATE | BTR_IGNORE_SEC_UNIQUE); ut_ad(!insert_planned || (mode == PAGE_CUR_LE)); 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 (btr_search_latch.writer == RW_LOCK_NOT_LOCKED && latch_mode <= BTR_MODIFY_LEAF && info->last_hash_succ && !estimate #ifdef PAGE_CUR_LE_OR_EXTENDS && mode != PAGE_CUR_LE_OR_EXTENDS #endif /* PAGE_CUR_LE_OR_EXTENDS */ && !UNIV_UNLIKELY(btr_search_disabled) && btr_search_guess_on_hash(index, info, tuple, mode, latch_mode, cursor, has_search_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++; return; } #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 */ if (has_search_latch) { /* Release possible search latch to obey latching order */ rw_lock_s_unlock(&btr_search_latch); } /* 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) */ savepoint = mtr_set_savepoint(mtr); if (latch_mode == BTR_MODIFY_TREE) { mtr_x_lock(dict_index_get_lock(index), mtr); } else if (latch_mode == BTR_CONT_MODIFY_TREE) { /* Do nothing */ ut_ad(mtr_memo_contains(mtr, dict_index_get_lock(index), MTR_MEMO_X_LOCK)); } else { mtr_s_lock(dict_index_get_lock(index), mtr); } page_cursor = btr_cur_get_page_cur(cursor); space = dict_index_get_space(index); page_no = dict_index_get_page(index); up_match = 0; up_bytes = 0; low_match = 0; low_bytes = 0; height = ULINT_UNDEFINED; rw_latch = RW_NO_LATCH; buf_mode = BUF_GET; /* 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 || mode == PAGE_CUR_LE_OR_EXTENDS); #else /* PAGE_CUR_LE_OR_EXTENDS */ ut_ad(mode == PAGE_CUR_L || mode == PAGE_CUR_LE); #endif /* PAGE_CUR_LE_OR_EXTENDS */ page_mode = mode; break; } /* Loop and search until we arrive at the desired level */ for (;;) { ulint zip_size; buf_block_t* block; retry_page_get: zip_size = dict_table_zip_size(index->table); block = buf_page_get_gen(space, zip_size, page_no, rw_latch, guess, buf_mode, __FILE__, __LINE__, mtr); if (block == NULL) { /* This must be a search to perform an insert; try insert to the insert buffer */ ut_ad(buf_mode == BUF_GET_IF_IN_POOL); ut_ad(insert_planned); ut_ad(cursor->thr); if (ibuf_should_try(index, ignore_sec_unique) && ibuf_insert(tuple, index, space, zip_size, page_no, cursor->thr)) { /* Insertion to the insert buffer succeeded */ cursor->flag = BTR_CUR_INSERT_TO_IBUF; if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } goto func_exit; } /* Insert to the insert buffer did not succeed: retry page get */ buf_mode = BUF_GET; goto retry_page_get; } page = buf_block_get_frame(block); #ifdef UNIV_ZIP_DEBUG if (rw_latch != RW_NO_LATCH) { const page_zip_des_t* page_zip = buf_block_get_page_zip(block); ut_a(!page_zip || page_zip_validate(page_zip, page)); } #endif /* UNIV_ZIP_DEBUG */ block->check_index_page_at_flush = TRUE; if (rw_latch != RW_NO_LATCH) { buf_block_dbg_add_level(block, SYNC_TREE_NODE); } ut_ad(0 == ut_dulint_cmp(index->id, btr_page_get_index_id(page))); if (UNIV_UNLIKELY(height == ULINT_UNDEFINED)) { /* We are in the root node */ height = btr_page_get_level(page, mtr); root_height = height; cursor->tree_height = root_height + 1; #ifdef BTR_CUR_ADAPT if (block != guess) { info->root_guess = block; } #endif } if (height == 0) { if (rw_latch == RW_NO_LATCH) { btr_cur_latch_leaves(page, space, zip_size, page_no, latch_mode, cursor, mtr); } if ((latch_mode != BTR_MODIFY_TREE) && (latch_mode != BTR_CONT_MODIFY_TREE)) { /* Release the tree s-latch */ mtr_release_s_latch_at_savepoint( mtr, savepoint, dict_index_get_lock(index)); } page_mode = mode; } page_cur_search_with_match(block, index, tuple, page_mode, &up_match, &up_bytes, &low_match, &low_bytes, page_cursor); 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), mtr)); if (level == height) { if (level > 0) { /* x-latch the page */ page = btr_page_get(space, zip_size, page_no, RW_X_LATCH, mtr); ut_a((ibool)!!page_is_comp(page) == dict_table_is_comp(index->table)); } break; } ut_ad(height > 0); height--; if ((height == 0) && (latch_mode <= BTR_MODIFY_LEAF)) { rw_latch = latch_mode; if (insert_planned && ibuf_should_try(index, ignore_sec_unique)) { /* Try insert to the insert buffer if the page is not in the buffer pool */ buf_mode = BUF_GET_IF_IN_POOL; } } guess = NULL; node_ptr = page_cur_get_rec(page_cursor); offsets = rec_get_offsets(node_ptr, cursor->index, offsets, ULINT_UNDEFINED, &heap); /* Go to the child node */ page_no = btr_node_ptr_get_child_page_no(node_ptr, offsets); } if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } if (level == 0) { cursor->low_match = low_match; cursor->low_bytes = low_bytes; cursor->up_match = up_match; cursor->up_bytes = up_bytes; #ifdef BTR_CUR_ADAPT if (!UNIV_UNLIKELY(btr_search_disabled)) { btr_search_info_update(index, cursor); } #endif 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); } func_exit: if (has_search_latch) { rw_lock_s_lock(&btr_search_latch); } } /********************************************************************* Opens a cursor at either end of an index. */ UNIV_INTERN void btr_cur_open_at_index_side( /*=======================*/ ibool 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: cursor */ mtr_t* mtr) /* in: mtr */ { page_cur_t* page_cursor; ulint page_no; ulint space; ulint zip_size; ulint height; ulint root_height = 0; /* remove warning */ rec_t* node_ptr; ulint estimate; ulint savepoint; mem_heap_t* heap = NULL; ulint offsets_[REC_OFFS_NORMAL_SIZE]; ulint* offsets = offsets_; rec_offs_init(offsets_); estimate = latch_mode & BTR_ESTIMATE; latch_mode = latch_mode & ~BTR_ESTIMATE; /* 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 */ savepoint = mtr_set_savepoint(mtr); if (latch_mode == BTR_MODIFY_TREE) { mtr_x_lock(dict_index_get_lock(index), mtr); } else { mtr_s_lock(dict_index_get_lock(index), mtr); } page_cursor = btr_cur_get_page_cur(cursor); cursor->index = index; space = dict_index_get_space(index); zip_size = dict_table_zip_size(index->table); page_no = dict_index_get_page(index); height = ULINT_UNDEFINED; for (;;) { buf_block_t* block; page_t* page; block = buf_page_get_gen(space, zip_size, page_no, RW_NO_LATCH, NULL, BUF_GET, __FILE__, __LINE__, mtr); page = buf_block_get_frame(block); ut_ad(0 == ut_dulint_cmp(index->id, btr_page_get_index_id(page))); block->check_index_page_at_flush = TRUE; if (height == ULINT_UNDEFINED) { /* We are in the root node */ height = btr_page_get_level(page, mtr); root_height = height; } if (height == 0) { btr_cur_latch_leaves(page, space, zip_size, page_no, 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. */ if ((latch_mode != BTR_MODIFY_TREE) && (latch_mode != BTR_CONT_MODIFY_TREE)) { /* Release the tree s-latch */ mtr_release_s_latch_at_savepoint( mtr, savepoint, dict_index_get_lock(index)); } } if (from_left) { page_cur_set_before_first(block, page_cursor); } else { page_cur_set_after_last(block, page_cursor); } if (height == 0) { 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, ULINT_UNDEFINED, &heap); /* Go to the child node */ page_no = btr_node_ptr_get_child_page_no(node_ptr, offsets); } if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } } /************************************************************************** Positions a cursor at a randomly chosen position within a B-tree. */ UNIV_INTERN void btr_cur_open_at_rnd_pos( /*====================*/ dict_index_t* index, /* in: index */ ulint latch_mode, /* in: BTR_SEARCH_LEAF, ... */ btr_cur_t* cursor, /* in/out: B-tree cursor */ mtr_t* mtr) /* in: mtr */ { page_cur_t* page_cursor; ulint page_no; ulint space; ulint zip_size; ulint height; rec_t* node_ptr; mem_heap_t* heap = NULL; ulint offsets_[REC_OFFS_NORMAL_SIZE]; ulint* offsets = offsets_; rec_offs_init(offsets_); if (latch_mode == BTR_MODIFY_TREE) { mtr_x_lock(dict_index_get_lock(index), mtr); } else { mtr_s_lock(dict_index_get_lock(index), mtr); } page_cursor = btr_cur_get_page_cur(cursor); cursor->index = index; space = dict_index_get_space(index); zip_size = dict_table_zip_size(index->table); page_no = dict_index_get_page(index); height = ULINT_UNDEFINED; for (;;) { buf_block_t* block; page_t* page; block = buf_page_get_gen(space, zip_size, page_no, RW_NO_LATCH, NULL, BUF_GET, __FILE__, __LINE__, mtr); page = buf_block_get_frame(block); ut_ad(0 == ut_dulint_cmp(index->id, btr_page_get_index_id(page))); if (height == ULINT_UNDEFINED) { /* We are in the root node */ height = btr_page_get_level(page, mtr); } if (height == 0) { btr_cur_latch_leaves(page, space, zip_size, page_no, latch_mode, cursor, mtr); } 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, ULINT_UNDEFINED, &heap); /* Go to the child node */ page_no = btr_node_ptr_get_child_page_no(node_ptr, offsets); } if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } } /*==================== 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. */ static rec_t* btr_cur_insert_if_possible( /*=======================*/ /* out: pointer to inserted record if succeed, else NULL */ 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 */ ulint n_ext, /* in: number of externally stored columns */ mtr_t* mtr) /* in: mtr */ { page_cur_t* page_cursor; buf_block_t* block; rec_t* rec; ut_ad(dtuple_check_typed(tuple)); block = btr_cur_get_block(cursor); ut_ad(mtr_memo_contains(mtr, block, 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, n_ext, mtr); if (UNIV_UNLIKELY(!rec)) { /* If record did not fit, reorganize */ if (btr_page_reorganize(block, cursor->index, mtr)) { page_cur_search(block, cursor->index, tuple, PAGE_CUR_LE, page_cursor); rec = page_cur_tuple_insert(page_cursor, tuple, cursor->index, n_ext, mtr); } } return(rec); } /***************************************************************** For an insert, checks the locks and does the undo logging if desired. */ UNIV_INLINE ulint btr_cur_ins_lock_and_undo( /*======================*/ /* out: DB_SUCCESS, DB_WAIT_LOCK, DB_FAIL, or error number */ 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 */ const dtuple_t* entry, /* in: entry to insert */ que_thr_t* thr, /* in: query thread or NULL */ ibool* inherit)/* out: TRUE if the inserted new record maybe should inherit LOCK_GAP type locks from the successor record */ { dict_index_t* index; ulint err; rec_t* rec; dulint 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; err = lock_rec_insert_check_and_lock(flags, rec, btr_cur_get_block(cursor), index, thr, inherit); if (err != DB_SUCCESS) { return(err); } if (dict_index_is_clust(index) && !dict_index_is_ibuf(index)) { err = trx_undo_report_row_operation(flags, TRX_UNDO_INSERT_OP, thr, index, entry, NULL, 0, NULL, &roll_ptr); if (err != DB_SUCCESS) { return(err); } /* Now we can fill in the roll ptr field in entry */ if (!(flags & BTR_KEEP_SYS_FLAG)) { row_upd_index_entry_sys_field(entry, index, DATA_ROLL_PTR, roll_ptr); } } return(DB_SUCCESS); } #ifdef UNIV_DEBUG /***************************************************************** Report information about a transaction. */ static void btr_cur_trx_report( /*===============*/ trx_t* trx, /* in: transaction */ const dict_index_t* index, /* in: index */ const char* op) /* in: operation */ { fprintf(stderr, "Trx with id " TRX_ID_FMT " going to ", TRX_ID_PREP_PRINTF(trx->id)); fputs(op, stderr); dict_index_name_print(stderr, trx, index); putc('\n', stderr); } #endif /* UNIV_DEBUG */ /***************************************************************** 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. */ UNIV_INTERN ulint btr_cur_optimistic_insert( /*======================*/ /* out: DB_SUCCESS, DB_WAIT_LOCK, DB_FAIL, or error number */ 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 */ 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, or NULL */ ulint n_ext, /* in: number of externally stored columns */ que_thr_t* thr, /* in: query thread or NULL */ mtr_t* mtr) /* in: mtr; if this function returns DB_SUCCESS on a leaf page of a secondary index in a compressed tablespace, the mtr must be committed 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; ulint max_size; rec_t* dummy_rec; ibool leaf; ibool reorg; ibool inherit; ulint zip_size; ulint rec_size; mem_heap_t* heap = NULL; ulint err; *big_rec = NULL; block = btr_cur_get_block(cursor); page = buf_block_get_frame(block); index = cursor->index; zip_size = buf_block_get_zip_size(block); #ifdef UNIV_DEBUG_VALGRIND if (zip_size) { UNIV_MEM_ASSERT_RW(page, UNIV_PAGE_SIZE); UNIV_MEM_ASSERT_RW(block->page.zip.data, zip_size); } #endif /* UNIV_DEBUG_VALGRIND */ if (!dtuple_check_typed_no_assert(entry)) { fputs("InnoDB: Error in a tuple to insert into ", stderr); dict_index_name_print(stderr, thr_get_trx(thr), index); } #ifdef UNIV_DEBUG if (btr_cur_print_record_ops && thr) { btr_cur_trx_report(thr_get_trx(thr), index, "insert into "); dtuple_print(stderr, entry); } #endif /* UNIV_DEBUG */ ut_ad(mtr_memo_contains(mtr, block, MTR_MEMO_PAGE_X_FIX)); max_size = page_get_max_insert_size_after_reorganize(page, 1); leaf = page_is_leaf(page); /* 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), zip_size)) { /* 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, 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 (UNIV_UNLIKELY(zip_size)) { /* Estimate the free space of an empty compressed page. Subtract one byte for the encoded heap_no in the modification log. */ ulint free_space_zip = page_zip_empty_size( cursor->index->n_fields, zip_size) - 1; ulint n_uniq = dict_index_get_n_unique_in_tree(index); ut_ad(dict_table_is_comp(index->table)); /* There should be enough room for two node pointer records on an empty non-leaf page. This prevents infinite page splits. */ if (UNIV_LIKELY(entry->n_fields >= n_uniq) && UNIV_UNLIKELY(REC_NODE_PTR_SIZE + rec_get_converted_size_comp_prefix( index, entry->fields, n_uniq, NULL) /* On a compressed page, there is a two-byte entry in the dense page directory for every record. But there is no record header. */ - (REC_N_NEW_EXTRA_BYTES - 2) > free_space_zip / 2)) { if (big_rec_vec) { dtuple_convert_back_big_rec( index, entry, big_rec_vec); } if (heap) { mem_heap_free(heap); } return(DB_TOO_BIG_RECORD); } } /* If there have been many consecutive inserts, and we are on the leaf level, check if we have to split the page to reserve enough free space for future updates of records. */ if (dict_index_is_clust(index) && (page_get_n_recs(page) >= 2) && UNIV_LIKELY(leaf) && (dict_index_get_space_reserve() + rec_size > max_size) && (btr_page_get_split_rec_to_right(cursor, &dummy_rec) || btr_page_get_split_rec_to_left(cursor, &dummy_rec))) { fail: err = DB_FAIL; fail_err: if (big_rec_vec) { dtuple_convert_back_big_rec(index, entry, big_rec_vec); } if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } return(err); } if (UNIV_UNLIKELY(max_size < BTR_CUR_PAGE_REORGANIZE_LIMIT || max_size < rec_size) && UNIV_LIKELY(page_get_n_recs(page) > 1) && page_get_max_insert_size(page, 1) < rec_size) { goto fail; } /* Check locks and write to the undo log, if specified */ err = btr_cur_ins_lock_and_undo(flags, cursor, entry, thr, &inherit); if (UNIV_UNLIKELY(err != DB_SUCCESS)) { goto fail_err; } page_cursor = btr_cur_get_page_cur(cursor); /* Now, try the insert */ { const rec_t* page_cursor_rec = page_cur_get_rec(page_cursor); *rec = page_cur_tuple_insert(page_cursor, entry, index, n_ext, mtr); reorg = page_cursor_rec != page_cur_get_rec(page_cursor); if (UNIV_UNLIKELY(reorg)) { ut_a(zip_size); ut_a(*rec); } } if (UNIV_UNLIKELY(!*rec) && UNIV_LIKELY(!reorg)) { /* If the record did not fit, reorganize */ if (UNIV_UNLIKELY(!btr_page_reorganize(block, index, mtr))) { ut_a(zip_size); goto fail; } ut_ad(zip_size || page_get_max_insert_size(page, 1) == max_size); reorg = TRUE; page_cur_search(block, index, entry, PAGE_CUR_LE, page_cursor); *rec = page_cur_tuple_insert(page_cursor, entry, index, n_ext, mtr); if (UNIV_UNLIKELY(!*rec)) { if (UNIV_LIKELY(zip_size != 0)) { goto fail; } fputs("InnoDB: Error: cannot insert tuple ", stderr); dtuple_print(stderr, entry); fputs(" into ", stderr); dict_index_name_print(stderr, thr_get_trx(thr), index); fprintf(stderr, "\nInnoDB: max insert size %lu\n", (ulong) max_size); ut_error; } } if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } #ifdef BTR_CUR_HASH_ADAPT if (!reorg && leaf && (cursor->flag == BTR_CUR_HASH)) { btr_search_update_hash_node_on_insert(cursor); } else { btr_search_update_hash_on_insert(cursor); } #endif if (!(flags & BTR_NO_LOCKING_FLAG) && inherit) { lock_update_insert(block, *rec); } #if 0 fprintf(stderr, "Insert into page %lu, max ins size %lu," " rec %lu ind type %lu\n", buf_block_get_page_no(block), max_size, rec_size + PAGE_DIR_SLOT_SIZE, index->type); #endif if (!dict_index_is_clust(index) && leaf) { /* 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 (zip_size) { /* 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. */ UNIV_INTERN ulint btr_cur_pessimistic_insert( /*=======================*/ /* out: DB_SUCCESS or error number */ 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 */ 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, or NULL */ ulint n_ext, /* in: number of externally stored columns */ que_thr_t* thr, /* in: query thread or NULL */ mtr_t* mtr) /* in: mtr */ { dict_index_t* index = cursor->index; ulint zip_size = dict_table_zip_size(index->table); big_rec_t* big_rec_vec = NULL; mem_heap_t* heap = NULL; ulint err; ibool dummy_inh; ibool success; ulint n_extents = 0; ulint n_reserved; ut_ad(dtuple_check_typed(entry)); *big_rec = NULL; ut_ad(mtr_memo_contains(mtr, dict_index_get_lock(btr_cur_get_index(cursor)), MTR_MEMO_X_LOCK)); ut_ad(mtr_memo_contains(mtr, btr_cur_get_block(cursor), MTR_MEMO_PAGE_X_FIX)); /* Try first an optimistic insert; reset the cursor flag: we do not assume anything of how it was positioned */ cursor->flag = BTR_CUR_BINARY; err = btr_cur_optimistic_insert(flags, cursor, entry, rec, big_rec, n_ext, thr, mtr); if (err != DB_FAIL) { return(err); } /* Retry with a pessimistic insert. Check locks and write to undo log, if specified */ err = btr_cur_ins_lock_and_undo(flags, cursor, entry, thr, &dummy_inh); 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 */ n_extents = cursor->tree_height / 16 + 3; success = fsp_reserve_free_extents(&n_reserved, index->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), dict_table_is_comp(index->table), dict_index_get_n_fields(index), zip_size)) { /* 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, entry, &n_ext); if (big_rec_vec == NULL) { if (n_extents > 0) { fil_space_release_free_extents(index->space, n_reserved); } return(DB_TOO_BIG_RECORD); } } if (dict_index_get_page(index) == buf_block_get_page_no(btr_cur_get_block(cursor))) { /* The page is the root page */ *rec = btr_root_raise_and_insert(cursor, entry, n_ext, mtr); } else { *rec = btr_page_split_and_insert(cursor, entry, n_ext, mtr); } if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } ut_ad(page_rec_get_next(btr_cur_get_rec(cursor)) == *rec); #ifdef BTR_CUR_ADAPT btr_search_update_hash_on_insert(cursor); #endif if (!(flags & BTR_NO_LOCKING_FLAG)) { lock_update_insert(btr_cur_get_block(cursor), *rec); } if (n_extents > 0) { fil_space_release_free_extents(index->space, n_reserved); } *big_rec = big_rec_vec; return(DB_SUCCESS); } /*==================== B-TREE UPDATE =========================*/ /***************************************************************** For an update, checks the locks and does the undo logging. */ UNIV_INLINE ulint btr_cur_upd_lock_and_undo( /*======================*/ /* out: DB_SUCCESS, DB_WAIT_LOCK, or error number */ ulint flags, /* in: undo logging and locking flags */ btr_cur_t* cursor, /* in: cursor on record to update */ const upd_t* update, /* in: update vector */ ulint cmpl_info,/* in: compiler info on secondary index updates */ que_thr_t* thr, /* in: query thread */ dulint* roll_ptr)/* out: roll pointer */ { dict_index_t* index; rec_t* rec; ulint err; ut_ad(cursor && update && thr && roll_ptr); rec = btr_cur_get_rec(cursor); index = cursor->index; if (!dict_index_is_clust(index)) { /* 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)); } /* Check if we have to wait for a lock: enqueue an explicit lock request if yes */ err = DB_SUCCESS; if (!(flags & BTR_NO_LOCKING_FLAG)) { mem_heap_t* heap = NULL; ulint offsets_[REC_OFFS_NORMAL_SIZE]; rec_offs_init(offsets_); err = lock_clust_rec_modify_check_and_lock( flags, btr_cur_get_block(cursor), rec, index, rec_get_offsets(rec, index, offsets_, ULINT_UNDEFINED, &heap), thr); if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } if (err != DB_SUCCESS) { return(err); } } /* Append the info about the update in the undo log */ err = trx_undo_report_row_operation(flags, TRX_UNDO_MODIFY_OP, thr, index, NULL, update, cmpl_info, rec, roll_ptr); return(err); } /*************************************************************** Writes a redo log record of updating a record in-place. */ UNIV_INLINE void btr_cur_update_in_place_log( /*========================*/ ulint flags, /* in: flags */ rec_t* rec, /* in: record */ dict_index_t* index, /* in: index where cursor positioned */ const upd_t* update, /* in: update vector */ trx_t* trx, /* in: transaction */ dulint roll_ptr, /* in: roll ptr */ mtr_t* mtr) /* in: mtr */ { byte* log_ptr; page_t* page = page_align(rec); ut_ad(flags < 256); ut_ad(!!page_is_comp(page) == dict_table_is_comp(index->table)); log_ptr = mlog_open_and_write_index(mtr, rec, index, page_is_comp(page) ? MLOG_COMP_REC_UPDATE_IN_PLACE : MLOG_REC_UPDATE_IN_PLACE, 1 + DATA_ROLL_PTR_LEN + 14 + 2 + MLOG_BUF_MARGIN); if (!log_ptr) { /* Logging in mtr is switched off during crash recovery */ return; } /* The code below assumes index is a clustered index: change index to the clustered index if we are updating a secondary index record (or we could as well skip writing the sys col values to the log in this case because they are not needed for a secondary index record update) */ index = dict_table_get_first_index(index->table); mach_write_to_1(log_ptr, flags); log_ptr++; log_ptr = row_upd_write_sys_vals_to_log(index, trx, roll_ptr, log_ptr, mtr); mach_write_to_2(log_ptr, page_offset(rec)); log_ptr += 2; row_upd_index_write_log(update, log_ptr, mtr); } /*************************************************************** Parses a redo log record of updating a record in-place. */ UNIV_INTERN byte* btr_cur_parse_update_in_place( /*==========================*/ /* out: end of log record or NULL */ byte* ptr, /* in: buffer */ byte* end_ptr,/* in: buffer end */ page_t* page, /* in/out: page or NULL */ page_zip_des_t* page_zip,/* in/out: compressed page, or NULL */ dict_index_t* index) /* in: index corresponding to page */ { ulint flags; rec_t* rec; upd_t* update; ulint pos; dulint trx_id; dulint roll_ptr; ulint rec_offset; mem_heap_t* heap; ulint* offsets; if (end_ptr < ptr + 1) { return(NULL); } flags = mach_read_from_1(ptr); ptr++; ptr = row_upd_parse_sys_vals(ptr, end_ptr, &pos, &trx_id, &roll_ptr); if (ptr == NULL) { return(NULL); } if (end_ptr < ptr + 2) { return(NULL); } rec_offset = mach_read_from_2(ptr); ptr += 2; ut_a(rec_offset <= UNIV_PAGE_SIZE); heap = mem_heap_create(256); ptr = row_upd_index_parse(ptr, end_ptr, heap, &update); if (!ptr || !page) { goto func_exit; } ut_a((ibool)!!page_is_comp(page) == dict_table_is_comp(index->table)); rec = page + rec_offset; /* We do not need to reserve btr_search_latch, as the page is only being recovered, and there cannot be a hash index to it. */ offsets = rec_get_offsets(rec, index, NULL, ULINT_UNDEFINED, &heap); if (!(flags & BTR_KEEP_SYS_FLAG)) { row_upd_rec_sys_fields_in_recovery(rec, page_zip, offsets, pos, trx_id, roll_ptr); } row_upd_rec_in_place(rec, index, offsets, update, page_zip); func_exit: mem_heap_free(heap); return(ptr); } /***************************************************************** See if there is enough place in the page modification log to log an update-in-place. */ static ibool btr_cur_update_alloc_zip( /*=====================*/ /* out: TRUE if enough place */ page_zip_des_t* page_zip,/* in/out: compressed page */ buf_block_t* block, /* in/out: buffer page */ dict_index_t* index, /* in: the index corresponding to the block */ ulint length, /* in: size needed */ mtr_t* mtr) /* in: mini-transaction */ { ut_a(page_zip == buf_block_get_page_zip(block)); ut_ad(page_zip); if (page_zip_available(page_zip, dict_index_is_clust(index), length, 0)) { return(TRUE); } if (!page_zip->m_nonempty) { /* The page has been freshly compressed, so recompressing it will not help. */ return(FALSE); } if (!page_zip_compress(page_zip, buf_block_get_frame(block), index, mtr)) { /* Unable to compress the page */ return(FALSE); } /* 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 page_zip_compress() above did not reduce the free space available on the page. */ if (!page_zip_available(page_zip, dict_index_is_clust(index), length, 0)) { /* Out of space: reset the free bits. */ if (!dict_index_is_clust(index) && page_is_leaf(buf_block_get_frame(block))) { ibuf_reset_free_bits(block); } return(FALSE); } return(TRUE); } /***************************************************************** 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. */ UNIV_INTERN ulint btr_cur_update_in_place( /*====================*/ /* out: DB_SUCCESS or error number */ 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 */ const upd_t* update, /* in: update vector */ ulint cmpl_info,/* in: compiler info on secondary index updates */ que_thr_t* thr, /* in: query thread */ mtr_t* mtr) /* in: mtr; must be committed before latching any further pages */ { dict_index_t* index; buf_block_t* block; page_zip_des_t* page_zip; ulint err; rec_t* rec; dulint roll_ptr = ut_dulint_zero; trx_t* trx; ulint was_delete_marked; mem_heap_t* heap = NULL; ulint offsets_[REC_OFFS_NORMAL_SIZE]; ulint* offsets = offsets_; rec_offs_init(offsets_); rec = btr_cur_get_rec(cursor); index = cursor->index; ut_ad(!!page_rec_is_comp(rec) == dict_table_is_comp(index->table)); trx = thr_get_trx(thr); offsets = rec_get_offsets(rec, index, offsets, ULINT_UNDEFINED, &heap); #ifdef UNIV_DEBUG if (btr_cur_print_record_ops && thr) { btr_cur_trx_report(trx, index, "update "); rec_print_new(stderr, rec, offsets); } #endif /* UNIV_DEBUG */ block = btr_cur_get_block(cursor); page_zip = buf_block_get_page_zip(block); /* Check that enough space is available on the compressed page. */ if (UNIV_LIKELY_NULL(page_zip) && !btr_cur_update_alloc_zip(page_zip, block, index, rec_offs_size(offsets), mtr)) { return(DB_ZIP_OVERFLOW); } /* Do lock checking and undo logging */ err = btr_cur_upd_lock_and_undo(flags, cursor, update, cmpl_info, thr, &roll_ptr); if (UNIV_UNLIKELY(err != DB_SUCCESS)) { if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } return(err); } if (block->is_hashed) { /* The function row_upd_changes_ord_field_binary works only if the update vector was built for a clustered index, we must NOT call it if index is secondary */ if (!dict_index_is_clust(index) || row_upd_changes_ord_field_binary(NULL, index, update)) { /* Remove possible hash index pointer to this record */ btr_search_update_hash_on_delete(cursor); } rw_lock_x_lock(&btr_search_latch); } if (!(flags & BTR_KEEP_SYS_FLAG)) { row_upd_rec_sys_fields(rec, NULL, index, offsets, trx, roll_ptr); } was_delete_marked = rec_get_deleted_flag( rec, page_is_comp(buf_block_get_frame(block))); row_upd_rec_in_place(rec, index, offsets, update, page_zip); if (block->is_hashed) { rw_lock_x_unlock(&btr_search_latch); } if (page_zip && !dict_index_is_clust(index) && page_is_leaf(buf_block_get_frame(block))) { /* Update the free bits in the insert buffer. */ ibuf_update_free_bits_zip(block, mtr); } btr_cur_update_in_place_log(flags, rec, index, update, trx, roll_ptr, mtr); 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(page_zip, rec, index, offsets, mtr); } if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } return(DB_SUCCESS); } /***************************************************************** 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. */ UNIV_INTERN ulint btr_cur_optimistic_update( /*======================*/ /* out: DB_SUCCESS, or DB_OVERFLOW if the updated record does not fit, DB_UNDERFLOW if the page would become too empty, or DB_ZIP_OVERFLOW if there is not enough space left on the compressed page */ 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 */ 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 */ mtr_t* mtr) /* in: mtr; must be committed before latching any further pages */ { dict_index_t* index; page_cur_t* page_cursor; ulint err; buf_block_t* block; page_t* page; page_zip_des_t* page_zip; rec_t* rec; rec_t* orig_rec; ulint max_size; ulint new_rec_size; ulint old_rec_size; dtuple_t* new_entry; dulint roll_ptr; trx_t* trx; mem_heap_t* heap; ulint i; ulint n_ext; ulint* offsets; block = btr_cur_get_block(cursor); page = buf_block_get_frame(block); orig_rec = rec = btr_cur_get_rec(cursor); index = cursor->index; ut_ad(!!page_rec_is_comp(rec) == dict_table_is_comp(index->table)); ut_ad(mtr_memo_contains(mtr, block, MTR_MEMO_PAGE_X_FIX)); heap = mem_heap_create(1024); offsets = rec_get_offsets(rec, index, NULL, ULINT_UNDEFINED, &heap); #ifdef UNIV_DEBUG if (btr_cur_print_record_ops && thr) { btr_cur_trx_report(thr_get_trx(thr), index, "update "); rec_print_new(stderr, rec, offsets); } #endif /* UNIV_DEBUG */ if (!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. */ mem_heap_free(heap); return(btr_cur_update_in_place(flags, cursor, update, cmpl_info, thr, mtr)); } if (rec_offs_any_extern(offsets)) { any_extern: /* Externally stored fields are treated in pessimistic update */ mem_heap_free(heap); return(DB_OVERFLOW); } 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; } } page_cursor = btr_cur_get_page_cur(cursor); new_entry = row_rec_to_index_entry(ROW_COPY_DATA, rec, index, offsets, &n_ext, heap); /* We checked above that there are no externally stored fields. */ ut_a(!n_ext); /* 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, FALSE, heap); 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)); #endif /* UNIV_ZIP_DEBUG */ if (UNIV_LIKELY_NULL(page_zip) && !btr_cur_update_alloc_zip(page_zip, block, index, new_rec_size, mtr)) { err = DB_ZIP_OVERFLOW; goto err_exit; } if (UNIV_UNLIKELY(new_rec_size >= (page_get_free_space_of_empty(page_is_comp(page)) / 2))) { err = DB_OVERFLOW; goto err_exit; } if (UNIV_UNLIKELY(page_get_data_size(page) - old_rec_size + new_rec_size < BTR_CUR_PAGE_COMPRESS_LIMIT)) { /* The page would become too empty */ err = DB_UNDERFLOW; goto err_exit; } max_size = old_rec_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))) { /* 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 err_exit; } /* Do lock checking and undo logging */ err = btr_cur_upd_lock_and_undo(flags, cursor, update, cmpl_info, thr, &roll_ptr); if (err != DB_SUCCESS) { err_exit: mem_heap_free(heap); return(err); } /* 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). */ lock_rec_store_on_page_infimum(block, rec); btr_search_update_hash_on_delete(cursor); /* The call to row_rec_to_index_entry(ROW_COPY_DATA, ...) above invokes rec_offs_make_valid() to point to the copied record that the fields of new_entry point to. We have to undo it here. */ ut_ad(rec_offs_validate(NULL, index, offsets)); rec_offs_make_valid(page_cur_get_rec(page_cursor), index, offsets); page_cur_delete_rec(page_cursor, index, offsets, mtr); page_cur_move_to_prev(page_cursor); trx = thr_get_trx(thr); if (!(flags & BTR_KEEP_SYS_FLAG)) { row_upd_index_entry_sys_field(new_entry, index, DATA_ROLL_PTR, roll_ptr); row_upd_index_entry_sys_field(new_entry, index, DATA_TRX_ID, trx->id); } /* There are no externally stored columns in new_entry */ rec = btr_cur_insert_if_possible(cursor, new_entry, 0/*n_ext*/, mtr); ut_a(rec); /* <- We calculated above the insert would fit */ if (page_zip && !dict_index_is_clust(index) && page_is_leaf(page)) { /* Update the free bits in the insert buffer. */ ibuf_update_free_bits_zip(block, mtr); } /* 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); mem_heap_free(heap); return(DB_SUCCESS); } /***************************************************************** 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; ulint space; ulint zip_size; ulint prev_page_no; 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; } space = buf_block_get_space(block); zip_size = buf_block_get_zip_size(block); prev_page_no = btr_page_get_prev(page, mtr); ut_ad(prev_page_no != FIL_NULL); prev_block = buf_page_get_with_no_latch(space, zip_size, prev_page_no, mtr); #ifdef UNIV_BTR_DEBUG ut_a(btr_page_get_next(prev_block->frame, mtr) == page_get_page_no(page)); #endif /* UNIV_BTR_DEBUG */ /* We must already have an x-latch on prev_block! */ ut_ad(mtr_memo_contains(mtr, 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. */ UNIV_INTERN ulint btr_cur_pessimistic_update( /*=======================*/ /* out: DB_SUCCESS or error code */ ulint flags, /* in: undo logging, locking, and rollback flags */ btr_cur_t* cursor, /* in: cursor on the record to update */ mem_heap_t** heap, /* in/out: pointer to memory heap, or NULL */ big_rec_t** big_rec,/* out: big rec vector whose fields have to be stored externally by the caller, or NULL */ const upd_t* update, /* in: update vector; this is allowed also contain trx id and roll ptr fields, but the values in update vector have no effect */ ulint cmpl_info,/* in: compiler info on secondary index updates */ que_thr_t* thr, /* in: query thread */ mtr_t* mtr) /* in: mtr; 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_t* page; page_zip_des_t* page_zip; rec_t* rec; page_cur_t* page_cursor; dtuple_t* new_entry; ulint err; ulint optim_err; dulint roll_ptr; trx_t* trx; ibool was_first; ulint n_extents = 0; ulint n_reserved; ulint n_ext; ulint* offsets = NULL; *big_rec = NULL; block = btr_cur_get_block(cursor); page = buf_block_get_frame(block); page_zip = buf_block_get_page_zip(block); rec = btr_cur_get_rec(cursor); index = cursor->index; ut_ad(mtr_memo_contains(mtr, dict_index_get_lock(index), MTR_MEMO_X_LOCK)); ut_ad(mtr_memo_contains(mtr, block, MTR_MEMO_PAGE_X_FIX)); #ifdef UNIV_ZIP_DEBUG ut_a(!page_zip || page_zip_validate(page_zip, page)); #endif /* UNIV_ZIP_DEBUG */ optim_err = btr_cur_optimistic_update(flags, cursor, update, cmpl_info, thr, mtr); switch (optim_err) { case DB_UNDERFLOW: case DB_OVERFLOW: case DB_ZIP_OVERFLOW: break; default: return(optim_err); } /* Do lock checking and undo logging */ err = btr_cur_upd_lock_and_undo(flags, cursor, update, cmpl_info, thr, &roll_ptr); if (err != DB_SUCCESS) { return(err); } if (optim_err == DB_OVERFLOW) { ulint reserve_flag; /* 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 */ n_extents = cursor->tree_height / 16 + 3; if (flags & BTR_NO_UNDO_LOG_FLAG) { reserve_flag = FSP_CLEANING; } else { reserve_flag = FSP_NORMAL; } if (!fsp_reserve_free_extents(&n_reserved, index->space, n_extents, reserve_flag, mtr)) { return(DB_OUT_OF_FILE_SPACE); } } if (!*heap) { *heap = mem_heap_create(1024); } offsets = rec_get_offsets(rec, index, NULL, ULINT_UNDEFINED, heap); trx = thr_get_trx(thr); new_entry = row_rec_to_index_entry(ROW_COPY_DATA, rec, index, offsets, &n_ext, *heap); /* The call to row_rec_to_index_entry(ROW_COPY_DATA, ...) above invokes rec_offs_make_valid() to point to the copied record that the fields of new_entry point to. We have to undo it here. */ ut_ad(rec_offs_validate(NULL, index, offsets)); rec_offs_make_valid(rec, index, offsets); /* 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, FALSE, *heap); if (!(flags & BTR_KEEP_SYS_FLAG)) { row_upd_index_entry_sys_field(new_entry, index, DATA_ROLL_PTR, roll_ptr); row_upd_index_entry_sys_field(new_entry, index, DATA_TRX_ID, trx->id); } 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); btr_rec_free_updated_extern_fields( index, rec, page_zip, offsets, update, trx_is_recv(trx) ? RB_RECOVERY : RB_NORMAL, mtr); } /* 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(page) || !rec_get_node_ptr_flag(rec)); offsets = rec_get_offsets(rec, index, offsets, ULINT_UNDEFINED, heap); n_ext += btr_push_update_extern_fields(new_entry, update, *heap); if (UNIV_LIKELY_NULL(page_zip)) { ut_ad(page_is_comp(page)); if (page_zip_rec_needs_ext( rec_get_converted_size(index, new_entry, n_ext), TRUE, dict_index_get_n_fields(index), page_zip_get_size(page_zip))) { goto make_external; } } else if (page_zip_rec_needs_ext( rec_get_converted_size(index, new_entry, n_ext), page_is_comp(page), 0, 0)) { make_external: big_rec_vec = dtuple_convert_big_rec(index, new_entry, &n_ext); if (UNIV_UNLIKELY(big_rec_vec == NULL)) { err = DB_TOO_BIG_RECORD; goto return_after_reservations; } } /* 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. */ lock_rec_store_on_page_infimum(block, rec); btr_search_update_hash_on_delete(cursor); #ifdef UNIV_ZIP_DEBUG ut_a(!page_zip || page_zip_validate(page_zip, page)); #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, n_ext, mtr); if (rec) { lock_rec_restore_from_page_infimum(btr_cur_get_block(cursor), rec, block); offsets = rec_get_offsets(rec, index, offsets, ULINT_UNDEFINED, heap); if (!rec_get_deleted_flag(rec, rec_offs_comp(offsets))) { /* The new inserted record owns its possible externally stored fields */ btr_cur_unmark_extern_fields(page_zip, rec, index, offsets, mtr); } btr_cur_compress_if_useful(cursor, mtr); if (page_zip && !dict_index_is_clust(index) && page_is_leaf(page)) { /* Update the free bits in the insert buffer. */ ibuf_update_free_bits_zip(block, mtr); } err = DB_SUCCESS; goto return_after_reservations; } else { ut_a(optim_err != DB_UNDERFLOW); /* Out of space: reset the free bits. */ if (!dict_index_is_clust(index) && page_is_leaf(page)) { ibuf_reset_free_bits(block); } } /* Was the record to be updated positioned as the first user record on its page? */ was_first = page_cur_is_before_first(page_cursor); /* The first parameter means that no lock checking and undo logging is made in the insert */ err = btr_cur_pessimistic_insert(BTR_NO_UNDO_LOG_FLAG | BTR_NO_LOCKING_FLAG | BTR_KEEP_SYS_FLAG, cursor, new_entry, &rec, &dummy_big_rec, n_ext, NULL, mtr); ut_a(rec); ut_a(err == DB_SUCCESS); ut_a(dummy_big_rec == NULL); if (!rec_get_deleted_flag(rec, rec_offs_comp(offsets))) { /* The new inserted record owns its possible externally stored fields */ buf_block_t* rec_block = btr_cur_get_block(cursor); #ifdef UNIV_ZIP_DEBUG ut_a(!page_zip || page_zip_validate(page_zip, page)); page = buf_block_get_frame(rec_block); #endif /* UNIV_ZIP_DEBUG */ page_zip = buf_block_get_page_zip(rec_block); offsets = rec_get_offsets(rec, index, offsets, ULINT_UNDEFINED, heap); btr_cur_unmark_extern_fields(page_zip, rec, index, offsets, mtr); } 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) { 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(page_zip, page)); #endif /* UNIV_ZIP_DEBUG */ if (n_extents > 0) { fil_space_release_free_extents(index->space, n_reserved); } *big_rec = big_rec_vec; return(err); } /*==================== B-TREE DELETE MARK AND UNMARK ===============*/ /******************************************************************** Writes the redo log record for delete marking or unmarking of an index record. */ UNIV_INLINE void btr_cur_del_mark_set_clust_rec_log( /*===============================*/ ulint flags, /* in: flags */ rec_t* rec, /* in: record */ dict_index_t* index, /* in: index of the record */ ibool val, /* in: value to set */ trx_t* trx, /* in: deleting transaction */ dulint roll_ptr,/* in: roll ptr to the undo log record */ mtr_t* mtr) /* in: mtr */ { byte* log_ptr; ut_ad(flags < 256); ut_ad(val <= 1); ut_ad(!!page_rec_is_comp(rec) == dict_table_is_comp(index->table)); log_ptr = mlog_open_and_write_index(mtr, rec, index, page_rec_is_comp(rec) ? MLOG_COMP_REC_CLUST_DELETE_MARK : MLOG_REC_CLUST_DELETE_MARK, 1 + 1 + DATA_ROLL_PTR_LEN + 14 + 2); if (!log_ptr) { /* Logging in mtr is switched off during crash recovery */ return; } mach_write_to_1(log_ptr, flags); log_ptr++; mach_write_to_1(log_ptr, val); log_ptr++; log_ptr = row_upd_write_sys_vals_to_log(index, trx, roll_ptr, log_ptr, mtr); mach_write_to_2(log_ptr, page_offset(rec)); log_ptr += 2; mlog_close(mtr, log_ptr); } /******************************************************************** Parses the redo log record for delete marking or unmarking of a clustered index record. */ UNIV_INTERN byte* btr_cur_parse_del_mark_set_clust_rec( /*=================================*/ /* out: end of log record or NULL */ byte* ptr, /* in: buffer */ byte* end_ptr,/* in: buffer end */ page_t* page, /* in/out: page or NULL */ page_zip_des_t* page_zip,/* in/out: compressed page, or NULL */ dict_index_t* index) /* in: index corresponding to page */ { ulint flags; ulint val; ulint pos; dulint trx_id; dulint roll_ptr; ulint offset; rec_t* rec; ut_ad(!page || !!page_is_comp(page) == dict_table_is_comp(index->table)); if (end_ptr < ptr + 2) { return(NULL); } flags = mach_read_from_1(ptr); ptr++; val = mach_read_from_1(ptr); ptr++; ptr = row_upd_parse_sys_vals(ptr, end_ptr, &pos, &trx_id, &roll_ptr); if (ptr == NULL) { return(NULL); } if (end_ptr < ptr + 2) { return(NULL); } offset = mach_read_from_2(ptr); ptr += 2; ut_a(offset <= UNIV_PAGE_SIZE); if (page) { rec = page + offset; /* We do not need to reserve btr_search_latch, as the page is only being recovered, and there cannot be a hash index to it. */ btr_rec_set_deleted_flag(rec, page_zip, val); if (!(flags & BTR_KEEP_SYS_FLAG)) { mem_heap_t* heap = NULL; ulint offsets_[REC_OFFS_NORMAL_SIZE]; rec_offs_init(offsets_); row_upd_rec_sys_fields_in_recovery( rec, page_zip, rec_get_offsets(rec, index, offsets_, ULINT_UNDEFINED, &heap), pos, trx_id, roll_ptr); if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } } } return(ptr); } /*************************************************************** 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. */ UNIV_INTERN ulint btr_cur_del_mark_set_clust_rec( /*===========================*/ /* out: DB_SUCCESS, DB_LOCK_WAIT, or error number */ ulint flags, /* in: undo logging and locking flags */ btr_cur_t* cursor, /* in: cursor */ ibool val, /* in: value to set */ que_thr_t* thr, /* in: query thread */ mtr_t* mtr) /* in: mtr */ { dict_index_t* index; buf_block_t* block; dulint roll_ptr; ulint err; rec_t* rec; page_zip_des_t* page_zip; trx_t* trx; mem_heap_t* heap = NULL; ulint offsets_[REC_OFFS_NORMAL_SIZE]; ulint* offsets = offsets_; rec_offs_init(offsets_); rec = btr_cur_get_rec(cursor); index = cursor->index; ut_ad(!!page_rec_is_comp(rec) == dict_table_is_comp(index->table)); offsets = rec_get_offsets(rec, index, offsets, ULINT_UNDEFINED, &heap); #ifdef UNIV_DEBUG if (btr_cur_print_record_ops && thr) { btr_cur_trx_report(thr_get_trx(thr), index, "del mark "); rec_print_new(stderr, rec, offsets); } #endif /* UNIV_DEBUG */ ut_ad(dict_index_is_clust(index)); ut_ad(!rec_get_deleted_flag(rec, rec_offs_comp(offsets))); err = lock_clust_rec_modify_check_and_lock(flags, btr_cur_get_block(cursor), rec, index, offsets, thr); if (err != DB_SUCCESS) { goto func_exit; } err = trx_undo_report_row_operation(flags, TRX_UNDO_MODIFY_OP, thr, index, NULL, NULL, 0, rec, &roll_ptr); if (err != DB_SUCCESS) { goto func_exit; } block = btr_cur_get_block(cursor); if (block->is_hashed) { rw_lock_x_lock(&btr_search_latch); } page_zip = buf_block_get_page_zip(block); btr_rec_set_deleted_flag(rec, page_zip, val); trx = thr_get_trx(thr); if (!(flags & BTR_KEEP_SYS_FLAG)) { row_upd_rec_sys_fields(rec, page_zip, index, offsets, trx, roll_ptr); } if (block->is_hashed) { rw_lock_x_unlock(&btr_search_latch); } btr_cur_del_mark_set_clust_rec_log(flags, rec, index, val, trx, roll_ptr, mtr); func_exit: if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } return(err); } /******************************************************************** Writes the redo log record for a delete mark setting of a secondary index record. */ UNIV_INLINE void btr_cur_del_mark_set_sec_rec_log( /*=============================*/ rec_t* rec, /* in: record */ ibool val, /* in: value to set */ mtr_t* mtr) /* in: mtr */ { byte* log_ptr; ut_ad(val <= 1); log_ptr = mlog_open(mtr, 11 + 1 + 2); if (!log_ptr) { /* Logging in mtr is switched off during crash recovery: in that case mlog_open returns NULL */ return; } log_ptr = mlog_write_initial_log_record_fast( rec, MLOG_REC_SEC_DELETE_MARK, log_ptr, mtr); mach_write_to_1(log_ptr, val); log_ptr++; mach_write_to_2(log_ptr, page_offset(rec)); log_ptr += 2; mlog_close(mtr, log_ptr); } /******************************************************************** Parses the redo log record for delete marking or unmarking of a secondary index record. */ UNIV_INTERN byte* btr_cur_parse_del_mark_set_sec_rec( /*===============================*/ /* out: end of log record or NULL */ byte* ptr, /* in: buffer */ byte* end_ptr,/* in: buffer end */ page_t* page, /* in/out: page or NULL */ page_zip_des_t* page_zip)/* in/out: compressed page, or NULL */ { ulint val; ulint offset; rec_t* rec; if (end_ptr < ptr + 3) { return(NULL); } val = mach_read_from_1(ptr); ptr++; offset = mach_read_from_2(ptr); ptr += 2; ut_a(offset <= UNIV_PAGE_SIZE); if (page) { rec = page + offset; /* We do not need to reserve btr_search_latch, as the page is only being recovered, and there cannot be a hash index to it. */ btr_rec_set_deleted_flag(rec, page_zip, val); } return(ptr); } /*************************************************************** Sets a secondary index record delete mark to TRUE or FALSE. */ UNIV_INTERN ulint btr_cur_del_mark_set_sec_rec( /*=========================*/ /* out: DB_SUCCESS, DB_LOCK_WAIT, or error number */ ulint flags, /* in: locking flag */ btr_cur_t* cursor, /* in: cursor */ ibool val, /* in: value to set */ que_thr_t* thr, /* in: query thread */ mtr_t* mtr) /* in: mtr */ { buf_block_t* block; rec_t* rec; ulint err; block = btr_cur_get_block(cursor); rec = btr_cur_get_rec(cursor); #ifdef UNIV_DEBUG if (btr_cur_print_record_ops && thr) { btr_cur_trx_report(thr_get_trx(thr), cursor->index, "del mark "); rec_print(stderr, rec, cursor->index); } #endif /* UNIV_DEBUG */ err = lock_sec_rec_modify_check_and_lock(flags, btr_cur_get_block(cursor), rec, cursor->index, thr); if (err != DB_SUCCESS) { return(err); } ut_ad(!!page_rec_is_comp(rec) == dict_table_is_comp(cursor->index->table)); if (block->is_hashed) { rw_lock_x_lock(&btr_search_latch); } btr_rec_set_deleted_flag(rec, buf_block_get_page_zip(block), val); if (block->is_hashed) { rw_lock_x_unlock(&btr_search_latch); } btr_cur_del_mark_set_sec_rec_log(rec, val, mtr); return(DB_SUCCESS); } /*************************************************************** Clear a secondary index record's delete mark. This function is only used by the insert buffer insert merge mechanism. */ UNIV_INTERN void btr_cur_del_unmark_for_ibuf( /*========================*/ rec_t* rec, /* in/out: record to delete unmark */ page_zip_des_t* page_zip, /* in/out: compressed page corresponding to rec, or NULL when the tablespace is uncompressed */ mtr_t* mtr) /* in: mtr */ { /* We do not need to reserve btr_search_latch, as the page has just been read to the buffer pool and there cannot be a hash index to it. */ btr_rec_set_deleted_flag(rec, page_zip, FALSE); btr_cur_del_mark_set_sec_rec_log(rec, FALSE, mtr); } /*==================== 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! */ UNIV_INTERN ibool btr_cur_compress_if_useful( /*=======================*/ /* out: TRUE if compression occurred */ btr_cur_t* cursor, /* in: cursor on the page to compress; cursor does not stay valid if compression occurs */ mtr_t* mtr) /* in: mtr */ { ut_ad(mtr_memo_contains(mtr, dict_index_get_lock(btr_cur_get_index(cursor)), MTR_MEMO_X_LOCK)); ut_ad(mtr_memo_contains(mtr, btr_cur_get_block(cursor), MTR_MEMO_PAGE_X_FIX)); return(btr_cur_compress_recommendation(cursor, mtr) && btr_compress(cursor, 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. */ UNIV_INTERN ibool btr_cur_optimistic_delete( /*======================*/ /* out: TRUE if success, i.e., the page did not become too empty */ 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 */ mtr_t* mtr) /* in: mtr */ { buf_block_t* block; rec_t* rec; mem_heap_t* heap = NULL; ulint offsets_[REC_OFFS_NORMAL_SIZE]; ulint* offsets = offsets_; ibool no_compress_needed; rec_offs_init(offsets_); ut_ad(mtr_memo_contains(mtr, btr_cur_get_block(cursor), MTR_MEMO_PAGE_X_FIX)); /* This is intended only for leaf page deletions */ block = btr_cur_get_block(cursor); ut_ad(page_is_leaf(buf_block_get_frame(block))); rec = btr_cur_get_rec(cursor); offsets = rec_get_offsets(rec, cursor->index, offsets, ULINT_UNDEFINED, &heap); no_compress_needed = !rec_offs_any_extern(offsets) && btr_cur_can_delete_without_compress( cursor, rec_offs_size(offsets), mtr); if (no_compress_needed) { page_t* page = buf_block_get_frame(block); page_zip_des_t* page_zip= buf_block_get_page_zip(block); ulint max_ins = 0; lock_update_delete(block, rec); btr_search_update_hash_on_delete(cursor); if (!page_zip) { max_ins = page_get_max_insert_size_after_reorganize( page, 1); } #ifdef UNIV_ZIP_DEBUG ut_a(!page_zip || page_zip_validate(page_zip, page)); #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 || page_zip_validate(page_zip, page)); #endif /* UNIV_ZIP_DEBUG */ if (dict_index_is_clust(cursor->index) || !page_is_leaf(page)) { /* The insert buffer does not handle inserts to clustered indexes or to non-leaf pages of secondary index B-trees. */ } else if (page_zip) { ibuf_update_free_bits_zip(block, mtr); } else { ibuf_update_free_bits_low(block, max_ins, mtr); } } 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. */ UNIV_INTERN ibool btr_cur_pessimistic_delete( /*=======================*/ /* out: TRUE if compression occurred */ ulint* 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 */ enum trx_rb_ctx rb_ctx, /* in: rollback context */ 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; dtuple_t* node_ptr; ulint n_extents = 0; ulint n_reserved; ibool success; ibool ret = FALSE; ulint level; mem_heap_t* heap; ulint* offsets; block = btr_cur_get_block(cursor); page = buf_block_get_frame(block); index = btr_cur_get_index(cursor); ut_ad(mtr_memo_contains(mtr, dict_index_get_lock(index), MTR_MEMO_X_LOCK)); ut_ad(mtr_memo_contains(mtr, block, MTR_MEMO_PAGE_X_FIX)); 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 */ n_extents = cursor->tree_height / 32 + 1; success = fsp_reserve_free_extents(&n_reserved, index->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)); #endif /* UNIV_ZIP_DEBUG */ offsets = rec_get_offsets(rec, index, NULL, ULINT_UNDEFINED, &heap); if (rec_offs_any_extern(offsets)) { btr_rec_free_externally_stored_fields(index, rec, offsets, page_zip, rb_ctx, mtr); #ifdef UNIV_ZIP_DEBUG ut_a(!page_zip || page_zip_validate(page_zip, page)); #endif /* UNIV_ZIP_DEBUG */ } if (UNIV_UNLIKELY(page_get_n_recs(page) < 2) && UNIV_UNLIKELY(dict_index_get_page(index) != buf_block_get_page_no(block))) { /* If there is only one record, drop the whole page in btr_discard_page, if this is not the root page */ btr_discard_page(cursor, mtr); *err = DB_SUCCESS; ret = TRUE; goto return_after_reservations; } lock_update_delete(block, rec); level = btr_page_get_level(page, mtr); if (level > 0 && UNIV_UNLIKELY(rec == page_rec_get_next( page_get_infimum_rec(page)))) { rec_t* next_rec = page_rec_get_next(rec); if (btr_page_get_prev(page, mtr) == FIL_NULL) { /* 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 */ /* This will make page_zip_validate() fail until page_cur_delete_rec() completes. This is harmless, because everything will take place within a single mini-transaction and because writing to the redo log is an atomic operation (performed by mtr_commit()). */ btr_set_min_rec_mark(next_rec, mtr); } else { /* Otherwise, if we delete the leftmost node pointer on a page, we have to change the father node pointer so that it is equal to the new leftmost node pointer on the page */ btr_node_ptr_delete(index, block, mtr); node_ptr = dict_index_build_node_ptr( index, next_rec, buf_block_get_page_no(block), heap, level); btr_insert_on_non_leaf_level(index, level + 1, node_ptr, mtr); } } btr_search_update_hash_on_delete(cursor); page_cur_delete_rec(btr_cur_get_page_cur(cursor), index, offsets, mtr); #ifdef UNIV_ZIP_DEBUG ut_a(!page_zip || page_zip_validate(page_zip, page)); #endif /* UNIV_ZIP_DEBUG */ ut_ad(btr_check_node_ptr(index, block, mtr)); *err = DB_SUCCESS; return_after_reservations: mem_heap_free(heap); if (ret == FALSE) { ret = btr_cur_compress_if_useful(cursor, mtr); } if (n_extents > 0) { fil_space_release_free_extents(index->space, n_reserved); } return(ret); } /*********************************************************************** 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; rec_t* rec; 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; } rec = btr_cur_get_rec(cursor); slot = cursor->path_arr + (root_height - height); slot->nth_rec = page_rec_get_n_recs_before(rec); slot->n_recs = page_get_n_recs(page_align(rec)); } /*********************************************************************** Estimates the number of rows in a given index range. */ UNIV_INTERN ib_int64_t btr_estimate_n_rows_in_range( /*=========================*/ /* out: estimated number of rows */ dict_index_t* index, /* in: index */ const dtuple_t* tuple1, /* in: range start, may also be empty tuple */ ulint mode1, /* in: search mode for range start */ const dtuple_t* tuple2, /* in: range end, may also be empty tuple */ ulint mode2) /* in: search mode for range end */ { 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; ibool diverged; ibool diverged_lot; ulint divergence_level; ib_int64_t n_rows; ulint i; mtr_t mtr; mtr_start(&mtr); cursor.path_arr = path1; if (dtuple_get_n_fields(tuple1) > 0) { btr_cur_search_to_nth_level(index, 0, tuple1, mode1, BTR_SEARCH_LEAF | BTR_ESTIMATE, &cursor, 0, &mtr); } else { btr_cur_open_at_index_side(TRUE, index, BTR_SEARCH_LEAF | BTR_ESTIMATE, &cursor, &mtr); } mtr_commit(&mtr); mtr_start(&mtr); cursor.path_arr = path2; if (dtuple_get_n_fields(tuple2) > 0) { btr_cur_search_to_nth_level(index, 0, tuple2, mode2, BTR_SEARCH_LEAF | BTR_ESTIMATE, &cursor, 0, &mtr); } else { btr_cur_open_at_index_side(FALSE, index, BTR_SEARCH_LEAF | BTR_ESTIMATE, &cursor, &mtr); } mtr_commit(&mtr); /* We have the path information for the range in path1 and path2 */ n_rows = 1; diverged = FALSE; /* This becomes true when the path is not the same any more */ diverged_lot = FALSE; /* This becomes true when the paths are not the same or adjacent any more */ divergence_level = 1000000; /* This is the level where paths diverged a lot */ 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) { if (i > divergence_level + 1) { /* In trees whose height is > 1 our algorithm tends to underestimate: multiply the estimate by 2: */ n_rows = n_rows * 2; } /* 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 > index->table->stat_n_rows / 2) { n_rows = index->table->stat_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 = index->table->stat_n_rows; } } return(n_rows); } if (!diverged && slot1->nth_rec != slot2->nth_rec) { diverged = TRUE; if (slot1->nth_rec < slot2->nth_rec) { n_rows = slot2->nth_rec - slot1->nth_rec; if (n_rows > 1) { diverged_lot = TRUE; divergence_level = i; } } else { /* Maybe the tree has changed between searches */ return(10); } } 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 = (n_rows * (slot1->n_recs + slot2->n_recs)) / 2; } } } /*********************************************************************** Estimates the number of different key values in a given index, for each n-column prefix of the index where n <= dict_index_get_n_unique(index). The estimates are stored in the array index->stat_n_diff_key_vals. */ UNIV_INTERN void btr_estimate_number_of_different_key_vals( /*======================================*/ dict_index_t* index) /* in: index */ { btr_cur_t cursor; page_t* page; rec_t* rec; ulint n_cols; ulint matched_fields; ulint matched_bytes; ib_int64_t* n_diff; ullint n_sample_pages; /* number of pages to sample */ ulint not_empty_flag = 0; ulint total_external_size = 0; ulint i; ulint j; ullint add_on; mtr_t mtr; mem_heap_t* heap = NULL; ulint offsets_rec_[REC_OFFS_NORMAL_SIZE]; ulint offsets_next_rec_[REC_OFFS_NORMAL_SIZE]; ulint* offsets_rec = offsets_rec_; ulint* offsets_next_rec= offsets_next_rec_; rec_offs_init(offsets_rec_); rec_offs_init(offsets_next_rec_); n_cols = dict_index_get_n_unique(index); n_diff = mem_zalloc((n_cols + 1) * sizeof(ib_int64_t)); /* 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_sample_pages > index->stat_index_size) { if (index->stat_index_size > 0) { n_sample_pages = index->stat_index_size; } else { n_sample_pages = 1; } } else { n_sample_pages = srv_stats_sample_pages; } /* We sample some pages in the index to get an estimate */ for (i = 0; i < n_sample_pages; i++) { rec_t* supremum; mtr_start(&mtr); btr_cur_open_at_rnd_pos(index, BTR_SEARCH_LEAF, &cursor, &mtr); /* 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. */ page = btr_cur_get_page(&cursor); supremum = page_get_supremum_rec(page); rec = page_rec_get_next(page_get_infimum_rec(page)); if (rec != supremum) { not_empty_flag = 1; offsets_rec = rec_get_offsets(rec, index, offsets_rec, ULINT_UNDEFINED, &heap); } while (rec != supremum) { rec_t* next_rec = page_rec_get_next(rec); if (next_rec == supremum) { break; } matched_fields = 0; matched_bytes = 0; offsets_next_rec = rec_get_offsets(next_rec, index, offsets_next_rec, n_cols, &heap); cmp_rec_rec_with_match(rec, next_rec, offsets_rec, offsets_next_rec, index, &matched_fields, &matched_bytes); for (j = matched_fields + 1; j <= n_cols; j++) { /* We add one if this index record has a different prefix from the previous */ n_diff[j]++; } 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. */ { ulint* 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)) { /* 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. */ if (btr_page_get_prev(page, &mtr) != FIL_NULL || btr_page_get_next(page, &mtr) != FIL_NULL) { n_diff[n_cols]++; } } offsets_rec = rec_get_offsets(rec, index, offsets_rec, ULINT_UNDEFINED, &heap); total_external_size += btr_rec_get_externally_stored_len( rec, offsets_rec); mtr_commit(&mtr); } /* 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) */ for (j = 0; j <= n_cols; j++) { index->stat_n_diff_key_vals[j] = ((n_diff[j] * (ib_int64_t)index->stat_n_leaf_pages + n_sample_pages - 1 + total_external_size + not_empty_flag) / (n_sample_pages + total_external_size)); /* 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; } index->stat_n_diff_key_vals[j] += add_on; } mem_free(n_diff); if (UNIV_LIKELY_NULL(heap)) { mem_heap_free(heap); } } /*================== EXTERNAL STORAGE OF BIG FIELDS ===================*/ /*************************************************************** Gets the externally stored size of a record, in units of a database page. */ static ulint btr_rec_get_externally_stored_len( /*==============================*/ /* out: externally stored part, in units of a database page */ rec_t* rec, /* in: record */ const ulint* offsets)/* in: array returned by rec_get_offsets() */ { ulint n_fields; byte* data; ulint local_len; ulint extern_len; ulint total_extern_len = 0; ulint i; ut_ad(!rec_offs_comp(offsets) || !rec_get_node_ptr_flag(rec)); n_fields = rec_offs_n_fields(offsets); for (i = 0; i < n_fields; i++) { if (rec_offs_nth_extern(offsets, i)) { data = rec_get_nth_field(rec, offsets, i, &local_len); local_len -= BTR_EXTERN_FIELD_REF_SIZE; extern_len = mach_read_from_4(data + local_len + BTR_EXTERN_LEN + 4); total_extern_len += ut_calc_align(extern_len, UNIV_PAGE_SIZE); } } return(total_extern_len / UNIV_PAGE_SIZE); } /*********************************************************************** Sets the ownership bit of an externally stored field in a record. */ static void btr_cur_set_ownership_of_extern_field( /*==================================*/ page_zip_des_t* page_zip,/* in/out: compressed page whose uncompressed part will be updated, or NULL */ rec_t* rec, /* in/out: clustered index record */ dict_index_t* index, /* in: index of the page */ const ulint* offsets,/* in: array returned by rec_get_offsets() */ ulint i, /* in: field number */ ibool 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_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 = byte_val & (~BTR_EXTERN_OWNER_FLAG); } else { byte_val = byte_val | BTR_EXTERN_OWNER_FLAG; } if (UNIV_LIKELY_NULL(page_zip)) { mach_write_to_1(data + local_len + BTR_EXTERN_LEN, byte_val); page_zip_write_blob_ptr(page_zip, rec, index, offsets, i, mtr); } else if (UNIV_LIKELY(mtr != NULL)) { mlog_write_ulint(data + local_len + BTR_EXTERN_LEN, byte_val, MLOG_1BYTE, mtr); } else { mach_write_to_1(data + local_len + BTR_EXTERN_LEN, byte_val); } } /*********************************************************************** Marks not updated extern fields as not-owned by this record. The ownership is 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. */ UNIV_INTERN void btr_cur_mark_extern_inherited_fields( /*=================================*/ page_zip_des_t* page_zip,/* in/out: compressed page whose uncompressed part will be updated, or NULL */ rec_t* rec, /* in/out: record in a clustered index */ dict_index_t* index, /* in: index of the page */ const ulint* offsets,/* in: array returned by rec_get_offsets() */ const upd_t* update, /* in: update vector */ mtr_t* mtr) /* in: mtr, or NULL if not logged */ { ulint n; ulint j; ulint i; ut_ad(rec_offs_validate(rec, NULL, offsets)); ut_ad(!rec_offs_comp(offsets) || !rec_get_node_ptr_flag(rec)); if (!rec_offs_any_extern(offsets)) { return; } n = rec_offs_n_fields(offsets); for (i = 0; i < n; i++) { if (rec_offs_nth_extern(offsets, i)) { /* Check it is not in updated fields */ if (update) { for (j = 0; j < upd_get_n_fields(update); j++) { if (upd_get_nth_field(update, j) ->field_no == i) { goto updated; } } } btr_cur_set_ownership_of_extern_field( page_zip, rec, index, offsets, i, FALSE, mtr); updated: ; } } } /*********************************************************************** The complement of the previous function: in an update entry may inherit some externally stored fields from a record. We must mark them as inherited in entry, so that they are not freed in a rollback. */ UNIV_INTERN void btr_cur_mark_dtuple_inherited_extern( /*=================================*/ dtuple_t* entry, /* in/out: updated entry to be inserted to clustered index */ const upd_t* update) /* in: update vector */ { ulint i; for (i = 0; i < dtuple_get_n_fields(entry); i++) { dfield_t* dfield = dtuple_get_nth_field(entry, i); byte* data; ulint len; ulint j; if (!dfield_is_ext(dfield)) { continue; } /* Check if it is in updated fields */ for (j = 0; j < upd_get_n_fields(update); j++) { if (upd_get_nth_field(update, j)->field_no == i) { goto is_updated; } } data = dfield_get_data(dfield); len = dfield_get_len(dfield); data[len - BTR_EXTERN_FIELD_REF_SIZE + BTR_EXTERN_LEN] |= BTR_EXTERN_INHERITED_FLAG; is_updated: ; } } /*********************************************************************** 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( /*=========================*/ page_zip_des_t* page_zip,/* in/out: compressed page whose uncompressed part will be updated, or NULL */ rec_t* rec, /* in/out: record in a clustered index */ dict_index_t* index, /* in: index of the page */ const ulint* offsets,/* in: array returned by rec_get_offsets() */ mtr_t* mtr) /* in: mtr, or NULL if not logged */ { ulint n; ulint i; ut_ad(!rec_offs_comp(offsets) || !rec_get_node_ptr_flag(rec)); n = rec_offs_n_fields(offsets); if (!rec_offs_any_extern(offsets)) { return; } for (i = 0; i < n; i++) { if (rec_offs_nth_extern(offsets, i)) { btr_cur_set_ownership_of_extern_field( page_zip, rec, index, offsets, i, TRUE, mtr); } } } /*********************************************************************** Marks all extern fields in a dtuple as owned by the record. */ UNIV_INTERN void btr_cur_unmark_dtuple_extern_fields( /*================================*/ dtuple_t* entry) /* in/out: clustered index entry */ { ulint i; for (i = 0; i < dtuple_get_n_fields(entry); i++) { dfield_t* dfield = dtuple_get_nth_field(entry, i); if (dfield_is_ext(dfield)) { byte* data = dfield_get_data(dfield); ulint len = dfield_get_len(dfield); data[len - BTR_EXTERN_FIELD_REF_SIZE + BTR_EXTERN_LEN] &= ~BTR_EXTERN_OWNER_FLAG; } } } /*********************************************************************** Flags the data tuple fields that are marked as extern storage in the update vector. We use this function to remember which fields we must mark as extern storage in a record inserted for an update. */ UNIV_INTERN ulint btr_push_update_extern_fields( /*==========================*/ /* out: number of flagged external columns */ dtuple_t* tuple, /* in/out: data tuple */ const upd_t* update, /* in: update vector */ mem_heap_t* heap) /* in: memory heap */ { ulint n_pushed = 0; ulint n; const upd_field_t* uf; ut_ad(tuple); ut_ad(update); uf = update->fields; n = upd_get_n_fields(update); for (; n--; uf++) { if (dfield_is_ext(&uf->new_val)) { dfield_t* field = dtuple_get_nth_field(tuple, uf->field_no); if (!dfield_is_ext(field)) { dfield_set_ext(field); n_pushed++; } switch (uf->orig_len) { byte* data; ulint len; byte* buf; case 0: break; case BTR_EXTERN_FIELD_REF_SIZE: /* Restore the original locally stored part of the column. In the undo log, InnoDB writes a longer prefix of externally stored columns, so that column prefixes in secondary indexes can be reconstructed. */ dfield_set_data(field, (byte*) dfield_get_data(field) + dfield_get_len(field) - BTR_EXTERN_FIELD_REF_SIZE, BTR_EXTERN_FIELD_REF_SIZE); dfield_set_ext(field); break; default: /* Reconstruct the original locally stored part of the column. The data will have to be copied. */ ut_a(uf->orig_len > BTR_EXTERN_FIELD_REF_SIZE); data = dfield_get_data(field); len = dfield_get_len(field); buf = mem_heap_alloc(heap, uf->orig_len); /* Copy the locally stored prefix. */ memcpy(buf, data, uf->orig_len - BTR_EXTERN_FIELD_REF_SIZE); /* Copy the BLOB pointer. */ memcpy(buf + uf->orig_len - BTR_EXTERN_FIELD_REF_SIZE, data + len - BTR_EXTERN_FIELD_REF_SIZE, BTR_EXTERN_FIELD_REF_SIZE); dfield_set_data(field, buf, uf->orig_len); dfield_set_ext(field); } } } return(n_pushed); } /*********************************************************************** Returns the length of a BLOB part stored on the header page. */ static ulint btr_blob_get_part_len( /*==================*/ /* out: part length */ 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. */ static ulint btr_blob_get_next_page_no( /*======================*/ /* out: page number or FIL_NULL if no more pages */ 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. */ static void btr_blob_free( /*==========*/ buf_block_t* block, /* in: buffer block */ ibool all, /* in: TRUE=remove also the compressed page if there is one */ mtr_t* mtr) /* in: mini-transaction to commit */ { ulint space = buf_block_get_space(block); ulint page_no = buf_block_get_page_no(block); ut_ad(mtr_memo_contains(mtr, block, MTR_MEMO_PAGE_X_FIX)); mtr_commit(mtr); buf_pool_mutex_enter(); mutex_enter(&block->mutex); /* Only free the block if it is still allocated to the same file page. */ if (buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE && buf_block_get_space(block) == space && buf_block_get_page_no(block) == page_no) { if (buf_LRU_free_block(&block->page, all, NULL) != BUF_LRU_FREED && all && block->page.zip.data) { /* Attempt to deallocate the uncompressed page if the whole block cannot be deallocted. */ buf_LRU_free_block(&block->page, FALSE, NULL); } } buf_pool_mutex_exit(); mutex_exit(&block->mutex); } /*********************************************************************** 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. */ UNIV_INTERN ulint btr_store_big_rec_extern_fields( /*============================*/ /* out: DB_SUCCESS or error */ dict_index_t* index, /* in: index of rec; the index tree MUST be X-latched */ buf_block_t* rec_block, /* in/out: block containing rec */ rec_t* rec, /* in/out: record */ const ulint* offsets, /* in: rec_get_offsets(rec, index); the "external storage" flags in offsets will not correspond to rec when this function returns */ big_rec_t* big_rec_vec, /* in: vector containing fields to be stored externally */ mtr_t* local_mtr __attribute__((unused))) /* in: mtr containing the latch to rec and to the tree */ { ulint rec_page_no; byte* field_ref; ulint extern_len; ulint store_len; ulint page_no; ulint space_id; ulint zip_size; ulint prev_page_no; ulint hint_page_no; ulint i; mtr_t mtr; mem_heap_t* heap = NULL; page_zip_des_t* page_zip; z_stream c_stream; ut_ad(rec_offs_validate(rec, index, offsets)); ut_ad(mtr_memo_contains(local_mtr, dict_index_get_lock(index), MTR_MEMO_X_LOCK)); ut_ad(mtr_memo_contains(local_mtr, 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)); page_zip = buf_block_get_page_zip(rec_block); ut_a(dict_table_zip_size(index->table) == buf_block_get_zip_size(rec_block)); space_id = buf_block_get_space(rec_block); zip_size = buf_block_get_zip_size(rec_block); rec_page_no = buf_block_get_page_no(rec_block); ut_a(fil_page_get_type(page_align(rec)) == FIL_PAGE_INDEX); if (UNIV_LIKELY_NULL(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, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 15, 7, Z_DEFAULT_STRATEGY); ut_a(err == Z_OK); } /* 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++) { ut_ad(rec_offs_nth_extern(offsets, big_rec_vec->fields[i].field_no)); { ulint local_len; field_ref = rec_get_nth_field( rec, offsets, big_rec_vec->fields[i].field_no, &local_len); ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE); local_len -= BTR_EXTERN_FIELD_REF_SIZE; field_ref += local_len; } extern_len = big_rec_vec->fields[i].len; ut_a(extern_len > 0); prev_page_no = FIL_NULL; if (UNIV_LIKELY_NULL(page_zip)) { int err = deflateReset(&c_stream); ut_a(err == Z_OK); c_stream.next_in = (void*) big_rec_vec->fields[i].data; c_stream.avail_in = extern_len; } for (;;) { buf_block_t* block; page_t* page; mtr_start(&mtr); if (prev_page_no == FIL_NULL) { hint_page_no = 1 + rec_page_no; } else { hint_page_no = prev_page_no + 1; } block = btr_page_alloc(index, hint_page_no, FSP_NO_DIR, 0, &mtr); if (UNIV_UNLIKELY(block == NULL)) { mtr_commit(&mtr); if (UNIV_LIKELY_NULL(page_zip)) { deflateEnd(&c_stream); mem_heap_free(heap); } return(DB_OUT_OF_FILE_SPACE); } page_no = buf_block_get_page_no(block); page = buf_block_get_frame(block); if (prev_page_no != FIL_NULL) { buf_block_t* prev_block; page_t* prev_page; prev_block = buf_page_get(space_id, zip_size, prev_page_no, RW_X_LATCH, &mtr); buf_block_dbg_add_level(prev_block, SYNC_EXTERN_STORAGE); prev_page = buf_block_get_frame(prev_block); if (UNIV_LIKELY_NULL(page_zip)) { mlog_write_ulint( prev_page + FIL_PAGE_NEXT, page_no, MLOG_4BYTES, &mtr); memcpy(buf_block_get_page_zip( prev_block) ->data + FIL_PAGE_NEXT, prev_page + FIL_PAGE_NEXT, 4); } else { mlog_write_ulint( prev_page + FIL_PAGE_DATA + BTR_BLOB_HDR_NEXT_PAGE_NO, page_no, MLOG_4BYTES, &mtr); } } if (UNIV_LIKELY_NULL(page_zip)) { int err; page_zip_des_t* blob_page_zip; mach_write_to_2(page + FIL_PAGE_TYPE, prev_page_no == FIL_NULL ? FIL_PAGE_TYPE_ZBLOB : FIL_PAGE_TYPE_ZBLOB2); c_stream.next_out = page + FIL_PAGE_DATA; c_stream.avail_out = page_zip_get_size(page_zip) - FIL_PAGE_DATA; 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); /* Write the "next BLOB page" pointer */ mlog_write_ulint(page + FIL_PAGE_NEXT, FIL_NULL, MLOG_4BYTES, &mtr); /* Initialize the unused "prev page" pointer */ mlog_write_ulint(page + FIL_PAGE_PREV, FIL_NULL, MLOG_4BYTES, &mtr); /* Write a back pointer to the record into the otherwise unused area. This information could be useful in debugging. Later, we might want to implement the possibility to relocate BLOB pages. Then, we would need to be able to adjust the BLOB pointer in the record. We do not store the heap number of the record, because it can change in page_zip_reorganize() or btr_page_reorganize(). However, also the page number of the record may change when B-tree nodes are split or merged. */ mlog_write_ulint(page + FIL_PAGE_FILE_FLUSH_LSN, space_id, MLOG_4BYTES, &mtr); mlog_write_ulint(page + FIL_PAGE_FILE_FLUSH_LSN + 4, rec_page_no, MLOG_4BYTES, &mtr); /* Zero out the unused part of the page. */ memset(page + page_zip_get_size(page_zip) - c_stream.avail_out, 0, c_stream.avail_out); mlog_log_string(page + FIL_PAGE_TYPE, page_zip_get_size(page_zip) - FIL_PAGE_TYPE, &mtr); /* 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, page, page_zip_get_size(page_zip)); if (err == Z_OK && prev_page_no != FIL_NULL) { goto next_zip_page; } rec_block = buf_page_get(space_id, zip_size, rec_page_no, RW_X_LATCH, &mtr); buf_block_dbg_add_level(rec_block, SYNC_NO_ORDER_CHECK); 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) { 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); } page_zip_write_blob_ptr( page_zip, rec, index, offsets, big_rec_vec->fields[i].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 { mlog_write_ulint(page + FIL_PAGE_TYPE, FIL_PAGE_TYPE_BLOB, MLOG_2BYTES, &mtr); if (extern_len > (UNIV_PAGE_SIZE - FIL_PAGE_DATA - BTR_BLOB_HDR_SIZE - FIL_PAGE_DATA_END)) { store_len = UNIV_PAGE_SIZE - FIL_PAGE_DATA - BTR_BLOB_HDR_SIZE - FIL_PAGE_DATA_END; } else { store_len = extern_len; } mlog_write_string(page + FIL_PAGE_DATA + BTR_BLOB_HDR_SIZE, (const byte*) big_rec_vec->fields[i].data + big_rec_vec->fields[i].len - extern_len, store_len, &mtr); mlog_write_ulint(page + FIL_PAGE_DATA + BTR_BLOB_HDR_PART_LEN, store_len, MLOG_4BYTES, &mtr); mlog_write_ulint(page + FIL_PAGE_DATA + BTR_BLOB_HDR_NEXT_PAGE_NO, FIL_NULL, MLOG_4BYTES, &mtr); extern_len -= store_len; rec_block = buf_page_get(space_id, zip_size, rec_page_no, RW_X_LATCH, &mtr); buf_block_dbg_add_level(rec_block, SYNC_NO_ORDER_CHECK); mlog_write_ulint(field_ref + BTR_EXTERN_LEN, 0, MLOG_4BYTES, &mtr); mlog_write_ulint(field_ref + BTR_EXTERN_LEN + 4, big_rec_vec->fields[i].len - extern_len, MLOG_4BYTES, &mtr); if (prev_page_no == FIL_NULL) { mlog_write_ulint(field_ref + BTR_EXTERN_SPACE_ID, space_id, MLOG_4BYTES, &mtr); mlog_write_ulint(field_ref + BTR_EXTERN_PAGE_NO, page_no, MLOG_4BYTES, &mtr); mlog_write_ulint(field_ref + BTR_EXTERN_OFFSET, FIL_PAGE_DATA, MLOG_4BYTES, &mtr); } prev_page_no = page_no; mtr_commit(&mtr); if (extern_len == 0) { break; } } } } if (UNIV_LIKELY_NULL(page_zip)) { deflateEnd(&c_stream); mem_heap_free(heap); } return(DB_SUCCESS); } /*********************************************************************** 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. */ UNIV_INTERN 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 ulint* offsets, /* in: rec_get_offsets(rec, index), or NULL */ page_zip_des_t* page_zip, /* in: compressed page corresponding to rec, or NULL if rec == NULL */ ulint i, /* in: field number of field_ref; ignored if rec == NULL */ enum trx_rb_ctx rb_ctx, /* in: rollback context */ mtr_t* local_mtr __attribute__((unused))) /* in: mtr containing the latch to data an an X-latch to the index tree */ { page_t* page; ulint space_id; ulint rec_zip_size = dict_table_zip_size(index->table); ulint ext_zip_size; ulint page_no; ulint next_page_no; mtr_t mtr; #ifdef UNIV_DEBUG ut_ad(mtr_memo_contains(local_mtr, dict_index_get_lock(index), MTR_MEMO_X_LOCK)); ut_ad(mtr_memo_contains_page(local_mtr, field_ref, MTR_MEMO_PAGE_X_FIX)); ut_ad(!rec || rec_offs_validate(rec, index, offsets)); if (rec) { ulint local_len; const byte* f = rec_get_nth_field(rec, offsets, i, &local_len); ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE); local_len -= BTR_EXTERN_FIELD_REF_SIZE; f += local_len; ut_ad(f == field_ref); } #endif /* UNIV_DEBUG */ if (UNIV_UNLIKELY(!memcmp(field_ref, field_ref_zero, BTR_EXTERN_FIELD_REF_SIZE))) { /* In the rollback of uncommitted transactions, we may encounter a clustered index record whose BLOBs have not been written. There is nothing to free then. */ ut_a(rb_ctx == RB_RECOVERY); return; } space_id = mach_read_from_4(field_ref + BTR_EXTERN_SPACE_ID); if (UNIV_UNLIKELY(space_id != dict_index_get_space(index))) { ext_zip_size = fil_space_get_zip_size(space_id); /* This must be an undo log record in the system tablespace, that is, in row_purge_upd_exist_or_extern(). Currently, externally stored records are stored in the same tablespace as the referring records. */ ut_ad(!page_get_space_id(page_align(field_ref))); ut_ad(!rec); ut_ad(!page_zip); } else { ext_zip_size = rec_zip_size; } if (!rec) { /* This is a call from row_purge_upd_exist_or_extern(). */ ut_ad(!page_zip); rec_zip_size = 0; } for (;;) { buf_block_t* rec_block; buf_block_t* ext_block; mtr_start(&mtr); rec_block = buf_page_get(page_get_space_id( page_align(field_ref)), rec_zip_size, page_get_page_no( page_align(field_ref)), 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 */ || (rb_ctx != RB_NONE && (mach_read_from_1(field_ref + BTR_EXTERN_LEN) & BTR_EXTERN_INHERITED_FLAG))) { /* Do not free */ mtr_commit(&mtr); return; } ext_block = buf_page_get(space_id, ext_zip_size, page_no, 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_low(index, ext_block, 0, &mtr); if (UNIV_LIKELY(page_zip != NULL)) { mach_write_to_4(field_ref + BTR_EXTERN_PAGE_NO, next_page_no); mach_write_to_4(field_ref + BTR_EXTERN_LEN + 4, 0); page_zip_write_blob_ptr(page_zip, rec, index, offsets, i, &mtr); } else { mlog_write_ulint(field_ref + BTR_EXTERN_PAGE_NO, next_page_no, MLOG_4BYTES, &mtr); mlog_write_ulint(field_ref + BTR_EXTERN_LEN + 4, 0, MLOG_4BYTES, &mtr); } } else { ut_a(fil_page_get_type(page) == FIL_PAGE_TYPE_BLOB); ut_a(!page_zip); next_page_no = mach_read_from_4( page + FIL_PAGE_DATA + BTR_BLOB_HDR_NEXT_PAGE_NO); /* We must supply the page level (= 0) as an argument because we did not store it on the page (we save the space overhead from an index page header. */ ut_a(space_id == page_get_space_id(page)); ut_a(page_no == page_get_page_no(page)); btr_page_free_low(index, ext_block, 0, &mtr); mlog_write_ulint(field_ref + BTR_EXTERN_PAGE_NO, next_page_no, MLOG_4BYTES, &mtr); /* Zero out the BLOB length. If the server crashes during the execution of this function, trx_rollback_or_clean_all_recovered() could dereference the half-deleted BLOB, fetching a wrong prefix for the BLOB. */ mlog_write_ulint(field_ref + BTR_EXTERN_LEN + 4, 0, MLOG_4BYTES, &mtr); } /* 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 ulint* offsets,/* in: rec_get_offsets(rec, index) */ page_zip_des_t* page_zip,/* in: compressed page whose uncompressed part will be updated, or NULL */ enum trx_rb_ctx rb_ctx, /* in: rollback context */ 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(mtr, rec, MTR_MEMO_PAGE_X_FIX)); /* 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)) { ulint len; byte* data = rec_get_nth_field(rec, offsets, i, &len); ut_a(len >= BTR_EXTERN_FIELD_REF_SIZE); btr_free_externally_stored_field( index, data + len - BTR_EXTERN_FIELD_REF_SIZE, rec, offsets, page_zip, i, rb_ctx, 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 */ page_zip_des_t* page_zip,/* in: compressed page whose uncompressed part will be updated, or NULL */ const ulint* offsets,/* in: rec_get_offsets(rec, index) */ const upd_t* update, /* in: update vector */ enum trx_rb_ctx rb_ctx, /* in: rollback context */ 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(mtr, 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, page_zip, ufield->field_no, rb_ctx, 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. */ static ulint btr_copy_blob_prefix( /*=================*/ /* out: number of bytes written to buf */ byte* buf, /* out: the externally stored part of the field, or a prefix of it */ ulint len, /* in: length of buf, in bytes */ ulint space_id,/* in: space id of the BLOB pages */ ulint page_no,/* in: page number of the first BLOB page */ ulint 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(space_id, 0, page_no, RW_S_LATCH, &mtr); buf_block_dbg_add_level(block, SYNC_EXTERN_STORAGE); page = buf_block_get_frame(block); /* Unfortunately, FIL_PAGE_TYPE was uninitialized for many pages until MySQL/InnoDB 5.1.7. */ /* ut_ad(fil_page_get_type(page) == FIL_PAGE_TYPE_BLOB); */ 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; page_no = btr_blob_get_next_page_no(blob_header); mtr_commit(&mtr); if (page_no == FIL_NULL || copy_len != part_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. */ static void btr_copy_zblob_prefix( /*==================*/ z_stream* d_stream,/* in/out: the decompressing stream */ ulint zip_size,/* in: compressed BLOB page size */ ulint space_id,/* in: space id of the BLOB pages */ ulint page_no,/* in: page number of the first BLOB page */ ulint offset) /* in: offset on the first BLOB page */ { ulint page_type = FIL_PAGE_TYPE_ZBLOB; ut_ad(ut_is_2pow(zip_size)); ut_ad(zip_size >= PAGE_ZIP_MIN_SIZE); ut_ad(zip_size <= UNIV_PAGE_SIZE); ut_ad(space_id); for (;;) { buf_page_t* bpage; int err; ulint 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(space_id, zip_size, page_no); if (UNIV_UNLIKELY(!bpage)) { ut_print_timestamp(stderr); fprintf(stderr, " InnoDB: Cannot load" " compressed BLOB" " page %lu space %lu\n", (ulong) page_no, (ulong) space_id); return; } if (UNIV_UNLIKELY (fil_page_get_type(bpage->zip.data) != page_type)) { ut_print_timestamp(stderr); fprintf(stderr, " InnoDB: Unexpected type %lu of" " compressed BLOB" " page %lu space %lu\n", (ulong) fil_page_get_type(bpage->zip.data), (ulong) page_no, (ulong) space_id); 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 = 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: ut_print_timestamp(stderr); fprintf(stderr, " InnoDB: inflate() of" " compressed BLOB" " page %lu space %lu returned %d (%s)\n", (ulong) page_no, (ulong) space_id, err, d_stream->msg); case Z_BUF_ERROR: goto end_of_blob; } if (next_page_no == FIL_NULL) { if (!d_stream->avail_in) { ut_print_timestamp(stderr); fprintf(stderr, " InnoDB: unexpected end of" " compressed BLOB" " page %lu space %lu\n", (ulong) page_no, (ulong) space_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); return; } buf_page_release_zip(bpage); /* On other BLOB pages except the first the BLOB header always is at the page header: */ page_no = next_page_no; offset = FIL_PAGE_NEXT; page_type = FIL_PAGE_TYPE_ZBLOB2; } } /*********************************************************************** 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. */ static ulint btr_copy_externally_stored_field_prefix_low( /*========================================*/ /* out: number of bytes written to buf */ byte* buf, /* out: the externally stored part of the field, or a prefix of it */ ulint len, /* in: length of buf, in bytes */ ulint zip_size,/* in: nonzero=compressed BLOB page size, zero for uncompressed BLOBs */ ulint space_id,/* in: space id of the first BLOB page */ ulint page_no,/* in: page number of the first BLOB page */ ulint offset) /* in: offset on the first BLOB page */ { if (UNIV_UNLIKELY(len == 0)) { return(0); } if (UNIV_UNLIKELY(zip_size)) { int err; z_stream d_stream; mem_heap_t* heap; /* 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); err = inflateInit(&d_stream); ut_a(err == Z_OK); d_stream.next_out = buf; d_stream.avail_out = len; d_stream.avail_in = 0; btr_copy_zblob_prefix(&d_stream, zip_size, space_id, page_no, offset); inflateEnd(&d_stream); mem_heap_free(heap); return(d_stream.total_out); } else { return(btr_copy_blob_prefix(buf, len, space_id, page_no, 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. */ UNIV_INTERN ulint btr_copy_externally_stored_field_prefix( /*====================================*/ /* out: the length of the copied field, or 0 if the column was being or has been deleted */ byte* buf, /* out: the field, or a prefix of it */ ulint len, /* in: length of buf, in bytes */ ulint zip_size,/* in: nonzero=compressed BLOB page size, zero for uncompressed BLOBs */ const byte* data, /* in: 'internally' stored part of the field containing also the reference to the external part; must be protected by a lock or a page latch */ ulint local_len)/* in: length of data, in bytes */ { ulint space_id; ulint page_no; ulint offset; 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); } space_id = mach_read_from_4(data + BTR_EXTERN_SPACE_ID); page_no = mach_read_from_4(data + BTR_EXTERN_PAGE_NO); offset = mach_read_from_4(data + BTR_EXTERN_OFFSET); return(local_len + btr_copy_externally_stored_field_prefix_low(buf + local_len, len - local_len, zip_size, 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. */ static byte* btr_copy_externally_stored_field( /*=============================*/ /* out: the whole field copied to heap */ ulint* len, /* out: length of the whole field */ const byte* data, /* in: 'internally' stored part of the field containing also the reference to the external part; must be protected by a lock or a page latch */ ulint zip_size,/* in: nonzero=compressed BLOB page size, zero for uncompressed BLOBs */ ulint local_len,/* in: length of data */ mem_heap_t* heap) /* in: mem heap */ { ulint space_id; ulint page_no; ulint offset; ulint extern_len; byte* buf; ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE); local_len -= BTR_EXTERN_FIELD_REF_SIZE; space_id = mach_read_from_4(data + local_len + BTR_EXTERN_SPACE_ID); page_no = mach_read_from_4(data + local_len + BTR_EXTERN_PAGE_NO); 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 */ extern_len = mach_read_from_4(data + local_len + BTR_EXTERN_LEN + 4); buf = 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, space_id, page_no, offset); return(buf); } /*********************************************************************** Copies an externally stored field of a record to mem heap. */ UNIV_INTERN byte* btr_rec_copy_externally_stored_field( /*=================================*/ /* out: the field copied to heap */ const rec_t* rec, /* in: record in a clustered index; must be protected by a lock or a page latch */ const ulint* offsets,/* in: array returned by rec_get_offsets() */ ulint zip_size,/* in: nonzero=compressed BLOB page size, zero for uncompressed BLOBs */ ulint no, /* in: field number */ ulint* len, /* out: length of the field */ mem_heap_t* heap) /* in: mem 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); return(btr_copy_externally_stored_field(len, data, zip_size, local_len, heap)); }