diff options
Diffstat (limited to 'sql/sql_db.cc')
| -rw-r--r-- | sql/sql_db.cc | 320 |
1 files changed, 55 insertions, 265 deletions
diff --git a/sql/sql_db.cc b/sql/sql_db.cc index 5e992d2391c..c4a7dc53972 100644 --- a/sql/sql_db.cc +++ b/sql/sql_db.cc @@ -58,106 +58,6 @@ static void mysql_change_db_impl(THD *thd, CHARSET_INFO *new_db_charset); -/* Database lock hash */ -HASH lock_db_cache; -mysql_mutex_t LOCK_lock_db; -int creating_database= 0; // how many database locks are made - - -/* Structure for database lock */ -typedef struct my_dblock_st -{ - char *name; /* Database name */ - uint name_length; /* Database length name */ -} my_dblock_t; - - -/* - lock_db key. -*/ - -extern "C" uchar* lock_db_get_key(my_dblock_t *, size_t *, my_bool not_used); - -uchar* lock_db_get_key(my_dblock_t *ptr, size_t *length, - my_bool not_used __attribute__((unused))) -{ - *length= ptr->name_length; - return (uchar*) ptr->name; -} - - -/* - Free lock_db hash element. -*/ - -extern "C" void lock_db_free_element(void *ptr); - -void lock_db_free_element(void *ptr) -{ - my_free(ptr, MYF(0)); -} - - -/* - Put a database lock entry into the hash. - - DESCRIPTION - Insert a database lock entry into hash. - LOCK_db_lock must be previously locked. - - RETURN VALUES - 0 on success. - 1 on error. -*/ - -static my_bool lock_db_insert(const char *dbname, uint length) -{ - my_dblock_t *opt; - my_bool error= 0; - DBUG_ENTER("lock_db_insert"); - - mysql_mutex_assert_owner(&LOCK_lock_db); - - if (!(opt= (my_dblock_t*) my_hash_search(&lock_db_cache, - (uchar*) dbname, length))) - { - /* Db is not in the hash, insert it */ - char *tmp_name; - if (!my_multi_malloc(MYF(MY_WME | MY_ZEROFILL), - &opt, (uint) sizeof(*opt), &tmp_name, (uint) length+1, - NullS)) - { - error= 1; - goto end; - } - - opt->name= tmp_name; - strmov(opt->name, dbname); - opt->name_length= length; - - if ((error= my_hash_insert(&lock_db_cache, (uchar*) opt))) - my_free(opt, MYF(0)); - } - -end: - DBUG_RETURN(error); -} - - -/* - Delete a database lock entry from hash. -*/ - -void lock_db_delete(const char *name, uint length) -{ - my_dblock_t *opt; - mysql_mutex_assert_owner(&LOCK_lock_db); - if ((opt= (my_dblock_t *)my_hash_search(&lock_db_cache, - (const uchar*) name, length))) - my_hash_delete(&lock_db_cache, (uchar*) opt); -} - - /* Database options hash */ static HASH dboptions; static my_bool dboptions_init= 0; @@ -233,21 +133,16 @@ static void init_database_names_psi_keys(void) } #endif -/* - Initialize database option hash and locked database hash. - - SYNOPSIS - my_database_names() +/** + Initialize database option cache. - NOTES - Must be called before any other database function is called. + @note Must be called before any other database function is called. - RETURN - 0 ok - 1 Fatal error + @retval 0 ok + @retval 1 Fatal error */ -bool my_database_names_init(void) +bool my_dboptions_cache_init(void) { #ifdef HAVE_PSI_INTERFACE init_database_names_psi_keys(); @@ -261,36 +156,30 @@ bool my_database_names_init(void) error= my_hash_init(&dboptions, lower_case_table_names ? &my_charset_bin : system_charset_info, 32, 0, 0, (my_hash_get_key) dboptions_get_key, - free_dbopt,0) || - my_hash_init(&lock_db_cache, lower_case_table_names ? - &my_charset_bin : system_charset_info, - 32, 0, 0, (my_hash_get_key) lock_db_get_key, - lock_db_free_element,0); - + free_dbopt,0); } return error; } -/* +/** Free database option hash and locked databases hash. */ -void my_database_names_free(void) +void my_dboptions_cache_free(void) { if (dboptions_init) { dboptions_init= 0; my_hash_free(&dboptions); mysql_rwlock_destroy(&LOCK_dboptions); - my_hash_free(&lock_db_cache); } } -/* - Cleanup cached options +/** + Cleanup cached options. */ void my_dbopt_cleanup(void) @@ -395,7 +284,7 @@ end: Deletes database options from the hash. */ -void del_dbopt(const char *path) +static void del_dbopt(const char *path) { my_dbopt_t *opt; mysql_rwlock_wrlock(&LOCK_dboptions); @@ -664,25 +553,8 @@ int mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create_info, DBUG_RETURN(-1); } - /* - Do not create database if another thread is holding read lock. - Wait for global read lock before acquiring LOCK_mysql_create_db. - After wait_if_global_read_lock() we have protection against another - global read lock. If we would acquire LOCK_mysql_create_db first, - another thread could step in and get the global read lock before we - reach wait_if_global_read_lock(). If this thread tries the same as we - (admin a db), it would then go and wait on LOCK_mysql_create_db... - Furthermore wait_if_global_read_lock() checks if the current thread - has the global read lock and refuses the operation with - ER_CANT_UPDATE_WITH_READLOCK if applicable. - */ - if (thd->global_read_lock.wait_if_global_read_lock(thd, FALSE, TRUE)) - { - error= -1; - goto exit2; - } - - mysql_mutex_lock(&LOCK_mysql_create_db); + if (lock_schema_name(thd, db)) + DBUG_RETURN(-1); /* Check directory */ path_len= build_table_filename(path, sizeof(path) - 1, db, "", "", 0); @@ -786,7 +658,10 @@ not_silent: qinfo.db = db; qinfo.db_len = strlen(db); - /* These DDL methods and logging protected with LOCK_mysql_create_db */ + /* + These DDL methods and logging are protected with the exclusive + metadata lock on the schema + */ if (mysql_bin_log.write(&qinfo)) { error= -1; @@ -797,9 +672,6 @@ not_silent: } exit: - mysql_mutex_unlock(&LOCK_mysql_create_db); - thd->global_read_lock.start_waiting_global_read_lock(thd); -exit2: DBUG_RETURN(error); } @@ -813,22 +685,8 @@ bool mysql_alter_db(THD *thd, const char *db, HA_CREATE_INFO *create_info) int error= 0; DBUG_ENTER("mysql_alter_db"); - /* - Do not alter database if another thread is holding read lock. - Wait for global read lock before acquiring LOCK_mysql_create_db. - After wait_if_global_read_lock() we have protection against another - global read lock. If we would acquire LOCK_mysql_create_db first, - another thread could step in and get the global read lock before we - reach wait_if_global_read_lock(). If this thread tries the same as we - (admin a db), it would then go and wait on LOCK_mysql_create_db... - Furthermore wait_if_global_read_lock() checks if the current thread - has the global read lock and refuses the operation with - ER_CANT_UPDATE_WITH_READLOCK if applicable. - */ - if ((error= thd->global_read_lock.wait_if_global_read_lock(thd, FALSE, TRUE))) - goto exit2; - - mysql_mutex_lock(&LOCK_mysql_create_db); + if (lock_schema_name(thd, db)) + DBUG_RETURN(TRUE); /* Recreate db options file: /dbpath/.db.opt @@ -866,16 +724,16 @@ bool mysql_alter_db(THD *thd, const char *db, HA_CREATE_INFO *create_info) qinfo.db = db; qinfo.db_len = strlen(db); - /* These DDL methods and logging protected with LOCK_mysql_create_db */ + /* + These DDL methods and logging are protected with the exclusive + metadata lock on the schema. + */ if ((error= mysql_bin_log.write(&qinfo))) goto exit; } my_ok(thd, result); exit: - mysql_mutex_unlock(&LOCK_mysql_create_db); - thd->global_read_lock.start_waiting_global_read_lock(thd); -exit2: DBUG_RETURN(error); } @@ -907,25 +765,9 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent) TABLE_LIST* dropped_tables= 0; DBUG_ENTER("mysql_rm_db"); - /* - Do not drop database if another thread is holding read lock. - Wait for global read lock before acquiring LOCK_mysql_create_db. - After wait_if_global_read_lock() we have protection against another - global read lock. If we would acquire LOCK_mysql_create_db first, - another thread could step in and get the global read lock before we - reach wait_if_global_read_lock(). If this thread tries the same as we - (admin a db), it would then go and wait on LOCK_mysql_create_db... - Furthermore wait_if_global_read_lock() checks if the current thread - has the global read lock and refuses the operation with - ER_CANT_UPDATE_WITH_READLOCK if applicable. - */ - if (thd->global_read_lock.wait_if_global_read_lock(thd, FALSE, TRUE)) - { - error= -1; - goto exit2; - } - mysql_mutex_lock(&LOCK_mysql_create_db); + if (lock_schema_name(thd, db)) + DBUG_RETURN(TRUE); length= build_table_filename(path, sizeof(path) - 1, db, "", "", 0); strmov(path+length, MY_DB_OPT_FILE); // Append db option file name @@ -1013,7 +855,10 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent) qinfo.db = db; qinfo.db_len = strlen(db); - /* These DDL methods and logging protected with LOCK_mysql_create_db */ + /* + These DDL methods and logging are protected with the exclusive + metadata lock on the schema. + */ if (mysql_bin_log.write(&qinfo)) { error= -1; @@ -1045,7 +890,10 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent) tbl_name_len= strlen(tbl->table_name) + 3; if (query_pos + tbl_name_len + 1 >= query_end) { - /* These DDL methods and logging protected with LOCK_mysql_create_db */ + /* + These DDL methods and logging are protected with the exclusive + metadata lock on the schema. + */ if (write_to_binlog(thd, query, query_pos -1 - query, db, db_len)) { error= -1; @@ -1062,7 +910,10 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent) if (query_pos != query_data_start) { - /* These DDL methods and logging protected with LOCK_mysql_create_db */ + /* + These DDL methods and logging are protected with the exclusive + metadata lock on the schema. + */ if (write_to_binlog(thd, query, query_pos -1 - query, db, db_len)) { error= -1; @@ -1080,9 +931,6 @@ exit: */ if (thd->db && !strcmp(thd->db, db) && error == 0) mysql_change_db_impl(thd, NULL, 0, thd->variables.collation_server); - mysql_mutex_unlock(&LOCK_mysql_create_db); - thd->global_read_lock.start_waiting_global_read_lock(thd); -exit2: DBUG_RETURN(error); } @@ -1099,12 +947,12 @@ static long mysql_rm_known_files(THD *thd, MY_DIR *dirp, const char *db, long deleted=0; ulong found_other_files=0; char filePath[FN_REFLEN]; - TABLE_LIST *tot_list=0, **tot_list_next; + TABLE_LIST *tot_list=0, **tot_list_next_local, **tot_list_next_global; List<String> raid_dirs; DBUG_ENTER("mysql_rm_known_files"); DBUG_PRINT("enter",("path: %s", org_path)); - tot_list_next= &tot_list; + tot_list_next_local= tot_list_next_global= &tot_list; for (uint idx=0 ; idx < (uint) dirp->number_off_files && !thd->killed ; @@ -1192,23 +1040,28 @@ static long mysql_rm_known_files(THD *thd, MY_DIR *dirp, const char *db, if (!table_list) goto err; table_list->db= (char*) (table_list+1); - table_list->table_name= strmov(table_list->db, db) + 1; - (void) filename_to_tablename(file->name, table_list->table_name, - MYSQL50_TABLE_NAME_PREFIX_LENGTH + - strlen(file->name) + 1); + table_list->db_length= strmov(table_list->db, db) - table_list->db; + table_list->table_name= table_list->db + table_list->db_length + 1; + table_list->table_name_length= filename_to_tablename(file->name, + table_list->table_name, + MYSQL50_TABLE_NAME_PREFIX_LENGTH + + strlen(file->name) + 1); table_list->open_type= OT_BASE_ONLY; /* To be able to correctly look up the table in the table cache. */ if (lower_case_table_names) - my_casedn_str(files_charset_info, table_list->table_name); + table_list->table_name_length= my_casedn_str(files_charset_info, + table_list->table_name); table_list->alias= table_list->table_name; // If lower_case_table_names=2 table_list->internal_tmp_table= is_prefix(file->name, tmp_file_prefix); table_list->mdl_request.init(MDL_key::TABLE, table_list->db, table_list->table_name, MDL_EXCLUSIVE); /* Link into list */ - (*tot_list_next)= table_list; - tot_list_next= &table_list->next_local; + (*tot_list_next_local)= table_list; + (*tot_list_next_global)= table_list; + tot_list_next_local= &table_list->next_local; + tot_list_next_global= &table_list->next_global; deleted++; } else @@ -1771,60 +1624,6 @@ bool mysql_opt_change_db(THD *thd, } -static int -lock_databases(THD *thd, const char *db1, uint length1, - const char *db2, uint length2) -{ - mysql_mutex_lock(&LOCK_lock_db); - while (!thd->killed && - (my_hash_search(&lock_db_cache,(uchar*) db1, length1) || - my_hash_search(&lock_db_cache,(uchar*) db2, length2))) - { - wait_for_condition(thd, &LOCK_lock_db, &COND_refresh); - mysql_mutex_lock(&LOCK_lock_db); - } - - if (thd->killed) - { - mysql_mutex_unlock(&LOCK_lock_db); - return 1; - } - - lock_db_insert(db1, length1); - lock_db_insert(db2, length2); - creating_database++; - - /* - Wait if a concurent thread is creating a table at the same time. - The assumption here is that it will not take too long until - there is a point in time when a table is not created. - */ - - while (!thd->killed && creating_table) - { - wait_for_condition(thd, &LOCK_lock_db, &COND_refresh); - mysql_mutex_lock(&LOCK_lock_db); - } - - if (thd->killed) - { - lock_db_delete(db1, length1); - lock_db_delete(db2, length2); - creating_database--; - mysql_mutex_unlock(&LOCK_lock_db); - mysql_cond_signal(&COND_refresh); - return(1); - } - - /* - We can unlock now as the hash will protect against anyone creating a table - in the databases we are using - */ - mysql_mutex_unlock(&LOCK_lock_db); - return 0; -} - - /** Upgrade a 5.0 database. This function is invoked whenever an ALTER DATABASE UPGRADE query is executed: @@ -1866,9 +1665,9 @@ bool mysql_upgrade_db(THD *thd, LEX_STRING *old_db) new_db.str= old_db->str + MYSQL50_TABLE_NAME_PREFIX_LENGTH; new_db.length= old_db->length - MYSQL50_TABLE_NAME_PREFIX_LENGTH; - if (lock_databases(thd, old_db->str, old_db->length, - new_db.str, new_db.length)) - DBUG_RETURN(1); + /* Lock the old name, the new name will be locked by mysql_create_db().*/ + if (lock_schema_name(thd, old_db->str)) + DBUG_RETURN(-1); /* Let's remember if we should do "USE newdb" afterwards. @@ -2035,15 +1834,6 @@ bool mysql_upgrade_db(THD *thd, LEX_STRING *old_db) error|= mysql_change_db(thd, & new_db, FALSE); exit: - mysql_mutex_lock(&LOCK_lock_db); - /* Remove the databases from db lock cache */ - lock_db_delete(old_db->str, old_db->length); - lock_db_delete(new_db.str, new_db.length); - creating_database--; - /* Signal waiting CREATE TABLE's to continue */ - mysql_cond_signal(&COND_refresh); - mysql_mutex_unlock(&LOCK_lock_db); - DBUG_RETURN(error); } |