/***************************************************************************** Copyright (c) 1995, 2010, Innobase Oy. All Rights Reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA *****************************************************************************/ /**************************************************//** @file include/fil0fil.h The low-level file system Created 10/25/1995 Heikki Tuuri *******************************************************/ #ifndef fil0fil_h #define fil0fil_h #include "univ.i" #ifndef UNIV_HOTBACKUP #include "sync0rw.h" #endif /* !UNIV_HOTBACKUP */ #include "dict0types.h" #include "ut0byte.h" #include "os0file.h" /** When mysqld is run, the default directory "." is the mysqld datadir, but in the MySQL Embedded Server Library and ibbackup it is not the default directory, and we must set the base file path explicitly */ extern const char* fil_path_to_mysql_datadir; /** Initial size of a single-table tablespace in pages */ #define FIL_IBD_FILE_INITIAL_SIZE 4 /** 'null' (undefined) page offset in the context of file spaces */ #define FIL_NULL ULINT32_UNDEFINED /* Space address data type; this is intended to be used when addresses accurate to a byte are stored in file pages. If the page part of the address is FIL_NULL, the address is considered undefined. */ typedef byte fil_faddr_t; /*!< 'type' definition in C: an address stored in a file page is a string of bytes */ #define FIL_ADDR_PAGE 0 /* first in address is the page offset */ #define FIL_ADDR_BYTE 4 /* then comes 2-byte byte offset within page*/ #define FIL_ADDR_SIZE 6 /* address size is 6 bytes */ /** A struct for storing a space address FIL_ADDR, when it is used in C program data structures. */ typedef struct fil_addr_struct fil_addr_t; /** File space address */ struct fil_addr_struct{ ulint page; /*!< page number within a space */ ulint boffset; /*!< byte offset within the page */ }; /** The null file address */ extern fil_addr_t fil_addr_null; /** The byte offsets on a file page for various variables @{ */ #define FIL_PAGE_SPACE_OR_CHKSUM 0 /*!< in < MySQL-4.0.14 space id the page belongs to (== 0) but in later versions the 'new' checksum of the page */ #define FIL_PAGE_OFFSET 4 /*!< page offset inside space */ #define FIL_PAGE_PREV 8 /*!< if there is a 'natural' predecessor of the page, its offset. Otherwise FIL_NULL. This field is not set on BLOB pages, which are stored as a singly-linked list. See also FIL_PAGE_NEXT. */ #define FIL_PAGE_NEXT 12 /*!< if there is a 'natural' successor of the page, its offset. Otherwise FIL_NULL. B-tree index pages (FIL_PAGE_TYPE contains FIL_PAGE_INDEX) on the same PAGE_LEVEL are maintained as a doubly linked list via FIL_PAGE_PREV and FIL_PAGE_NEXT in the collation order of the smallest user record on each page. */ #define FIL_PAGE_LSN 16 /*!< lsn of the end of the newest modification log record to the page */ #define FIL_PAGE_TYPE 24 /*!< file page type: FIL_PAGE_INDEX,..., 2 bytes. The contents of this field can only be trusted in the following case: if the page is an uncompressed B-tree index page, then it is guaranteed that the value is FIL_PAGE_INDEX. The opposite does not hold. In tablespaces created by MySQL/InnoDB 5.1.7 or later, the contents of this field is valid for all uncompressed pages. */ #define FIL_PAGE_FILE_FLUSH_LSN 26 /*!< this is only defined for the first page in a system tablespace data file (ibdata*, not *.ibd): the file has been flushed to disk at least up to this lsn */ #define FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID 34 /*!< starting from 4.1.x this contains the space id of the page */ #define FIL_PAGE_DATA 38 /*!< start of the data on the page */ /* @} */ /** File page trailer @{ */ #define FIL_PAGE_END_LSN_OLD_CHKSUM 8 /*!< the low 4 bytes of this are used to store the page checksum, the last 4 bytes should be identical to the last 4 bytes of FIL_PAGE_LSN */ #define FIL_PAGE_DATA_END 8 /*!< size of the page trailer */ /* @} */ /** File page types (values of FIL_PAGE_TYPE) @{ */ #define FIL_PAGE_INDEX 17855 /*!< B-tree node */ #define FIL_PAGE_UNDO_LOG 2 /*!< Undo log page */ #define FIL_PAGE_INODE 3 /*!< Index node */ #define FIL_PAGE_IBUF_FREE_LIST 4 /*!< Insert buffer free list */ /* File page types introduced in MySQL/InnoDB 5.1.7 */ #define FIL_PAGE_TYPE_ALLOCATED 0 /*!< Freshly allocated page */ #define FIL_PAGE_IBUF_BITMAP 5 /*!< Insert buffer bitmap */ #define FIL_PAGE_TYPE_SYS 6 /*!< System page */ #define FIL_PAGE_TYPE_TRX_SYS 7 /*!< Transaction system data */ #define FIL_PAGE_TYPE_FSP_HDR 8 /*!< File space header */ #define FIL_PAGE_TYPE_XDES 9 /*!< Extent descriptor page */ #define FIL_PAGE_TYPE_BLOB 10 /*!< Uncompressed BLOB page */ #define FIL_PAGE_TYPE_ZBLOB 11 /*!< First compressed BLOB page */ #define FIL_PAGE_TYPE_ZBLOB2 12 /*!< Subsequent compressed BLOB page */ /* @} */ /** Space types @{ */ #define FIL_TABLESPACE 501 /*!< tablespace */ #define FIL_LOG 502 /*!< redo log */ /* @} */ /** The number of fsyncs done to the log */ extern ulint fil_n_log_flushes; /** Number of pending redo log flushes */ extern ulint fil_n_pending_log_flushes; /** Number of pending tablespace flushes */ extern ulint fil_n_pending_tablespace_flushes; #ifndef UNIV_HOTBACKUP /*******************************************************************//** Returns the version number of a tablespace, -1 if not found. @return version number, -1 if the tablespace does not exist in the memory cache */ UNIV_INTERN ib_int64_t fil_space_get_version( /*==================*/ ulint id); /*!< in: space id */ /*******************************************************************//** Returns the latch of a file space. @return latch protecting storage allocation */ UNIV_INTERN rw_lock_t* fil_space_get_latch( /*================*/ ulint id, /*!< in: space id */ ulint* zip_size);/*!< out: compressed page size, or 0 for uncompressed tablespaces */ /*******************************************************************//** Returns the type of a file space. @return FIL_TABLESPACE or FIL_LOG */ UNIV_INTERN ulint fil_space_get_type( /*===============*/ ulint id); /*!< in: space id */ #endif /* !UNIV_HOTBACKUP */ /*******************************************************************//** Appends a new file to the chain of files of a space. File must be closed. */ UNIV_INTERN void fil_node_create( /*============*/ const char* name, /*!< in: file name (file must be closed) */ ulint size, /*!< in: file size in database blocks, rounded downwards to an integer */ ulint id, /*!< in: space id where to append */ ibool is_raw);/*!< in: TRUE if a raw device or a raw disk partition */ #ifdef UNIV_LOG_ARCHIVE /****************************************************************//** Drops files from the start of a file space, so that its size is cut by the amount given. */ UNIV_INTERN void fil_space_truncate_start( /*=====================*/ ulint id, /*!< in: space id */ ulint trunc_len); /*!< in: truncate by this much; it is an error if this does not equal to the combined size of some initial files in the space */ #endif /* UNIV_LOG_ARCHIVE */ /*******************************************************************//** Creates a space memory object and puts it to the 'fil system' hash table. If there is an error, prints an error message to the .err log. @return TRUE if success */ UNIV_INTERN ibool fil_space_create( /*=============*/ const char* name, /*!< in: space name */ ulint id, /*!< in: space id */ ulint zip_size,/*!< in: compressed page size, or 0 for uncompressed tablespaces */ ulint purpose);/*!< in: FIL_TABLESPACE, or FIL_LOG if log */ /*******************************************************************//** Assigns a new space id for a new single-table tablespace. This works simply by incrementing the global counter. If 4 billion id's is not enough, we may need to recycle id's. @return TRUE if assigned, FALSE if not */ UNIV_INTERN ibool fil_assign_new_space_id( /*====================*/ ulint* space_id); /*!< in/out: space id */ /*******************************************************************//** Returns the size of the space in pages. The tablespace must be cached in the memory cache. @return space size, 0 if space not found */ UNIV_INTERN ulint fil_space_get_size( /*===============*/ ulint id); /*!< in: space id */ /*******************************************************************//** Returns the flags of the space. The tablespace must be cached in the memory cache. @return flags, ULINT_UNDEFINED if space not found */ UNIV_INTERN ulint fil_space_get_flags( /*================*/ ulint id); /*!< in: space id */ /*******************************************************************//** Returns the compressed page size of the space, or 0 if the space is not compressed. The tablespace must be cached in the memory cache. @return compressed page size, ULINT_UNDEFINED if space not found */ UNIV_INTERN ulint fil_space_get_zip_size( /*===================*/ ulint id); /*!< in: space id */ /*******************************************************************//** Checks if the pair space, page_no refers to an existing page in a tablespace file space. The tablespace must be cached in the memory cache. @return TRUE if the address is meaningful */ UNIV_INTERN ibool fil_check_adress_in_tablespace( /*===========================*/ ulint id, /*!< in: space id */ ulint page_no);/*!< in: page number */ /****************************************************************//** Initializes the tablespace memory cache. */ UNIV_INTERN void fil_init( /*=====*/ ulint hash_size, /*!< in: hash table size */ ulint max_n_open); /*!< in: max number of open files */ /*******************************************************************//** Initializes the tablespace memory cache. */ UNIV_INTERN void fil_close(void); /*===========*/ /*******************************************************************//** Opens all log files and system tablespace data files. They stay open until the database server shutdown. This should be called at a server startup after the space objects for the log and the system tablespace have been created. The purpose of this operation is to make sure we never run out of file descriptors if we need to read from the insert buffer or to write to the log. */ UNIV_INTERN void fil_open_log_and_system_tablespace_files(void); /*==========================================*/ /*******************************************************************//** Closes all open files. There must not be any pending i/o's or not flushed modifications in the files. */ UNIV_INTERN void fil_close_all_files(void); /*=====================*/ /*******************************************************************//** Sets the max tablespace id counter if the given number is bigger than the previous value. */ UNIV_INTERN void fil_set_max_space_id_if_bigger( /*===========================*/ ulint max_id);/*!< in: maximum known id */ #ifndef UNIV_HOTBACKUP /****************************************************************//** Writes the flushed lsn and the latest archived log number to the page header of the first page of each data file in the system tablespace. @return DB_SUCCESS or error number */ UNIV_INTERN ulint fil_write_flushed_lsn_to_data_files( /*================================*/ ib_uint64_t lsn, /*!< in: lsn to write */ ulint arch_log_no); /*!< in: latest archived log file number */ /*******************************************************************//** Reads the flushed lsn and arch no fields from a data file at database startup. */ UNIV_INTERN void fil_read_flushed_lsn_and_arch_log_no( /*=================================*/ os_file_t data_file, /*!< in: open data file */ ibool one_read_already, /*!< in: TRUE if min and max parameters below already contain sensible data */ #ifdef UNIV_LOG_ARCHIVE ulint* min_arch_log_no, /*!< in/out: */ ulint* max_arch_log_no, /*!< in/out: */ #endif /* UNIV_LOG_ARCHIVE */ ib_uint64_t* min_flushed_lsn, /*!< in/out: */ ib_uint64_t* max_flushed_lsn); /*!< in/out: */ /*******************************************************************//** Increments the count of pending insert buffer page merges, if space is not being deleted. @return TRUE if being deleted, and ibuf merges should be skipped */ UNIV_INTERN ibool fil_inc_pending_ibuf_merges( /*========================*/ ulint id); /*!< in: space id */ /*******************************************************************//** Decrements the count of pending insert buffer page merges. */ UNIV_INTERN void fil_decr_pending_ibuf_merges( /*=========================*/ ulint id); /*!< in: space id */ #endif /* !UNIV_HOTBACKUP */ /*******************************************************************//** Parses the body of a log record written about an .ibd file operation. That is, the log record part after the standard (type, space id, page no) header of the log record. If desired, also replays the delete or rename operation if the .ibd file exists and the space id in it matches. Replays the create operation if a file at that path does not exist yet. If the database directory for the file to be created does not exist, then we create the directory, too. Note that ibbackup --apply-log sets fil_path_to_mysql_datadir to point to the datadir that we should use in replaying the file operations. @return end of log record, or NULL if the record was not completely contained between ptr and end_ptr */ UNIV_INTERN byte* fil_op_log_parse_or_replay( /*=======================*/ byte* ptr, /*!< in: buffer containing the log record body, or an initial segment of it, if the record does not fir completely between ptr and end_ptr */ byte* end_ptr, /*!< in: buffer end */ ulint type, /*!< in: the type of this log record */ ulint space_id, /*!< in: the space id of the tablespace in question, or 0 if the log record should only be parsed but not replayed */ ulint log_flags); /*!< in: redo log flags (stored in the page number parameter) */ /*******************************************************************//** Deletes a single-table tablespace. The tablespace must be cached in the memory cache. @return TRUE if success */ UNIV_INTERN ibool fil_delete_tablespace( /*==================*/ ulint id); /*!< in: space id */ #ifndef UNIV_HOTBACKUP /*******************************************************************//** Discards a single-table tablespace. The tablespace must be cached in the memory cache. Discarding is like deleting a tablespace, but 1) we do not drop the table from the data dictionary; 2) we remove all insert buffer entries for the tablespace immediately; in DROP TABLE they are only removed gradually in the background; 3) when the user does IMPORT TABLESPACE, the tablespace will have the same id as it originally had. @return TRUE if success */ UNIV_INTERN ibool fil_discard_tablespace( /*===================*/ ulint id); /*!< in: space id */ #endif /* !UNIV_HOTBACKUP */ /*******************************************************************//** Renames a single-table tablespace. The tablespace must be cached in the tablespace memory cache. @return TRUE if success */ UNIV_INTERN ibool fil_rename_tablespace( /*==================*/ const char* old_name, /*!< in: old table name in the standard databasename/tablename format of InnoDB, or NULL if we do the rename based on the space id only */ ulint id, /*!< in: space id */ const char* new_name); /*!< in: new table name in the standard databasename/tablename format of InnoDB */ /*******************************************************************//** Creates a new single-table tablespace to a database directory of MySQL. Database directories are under the 'datadir' of MySQL. The datadir is the directory of a running mysqld program. We can refer to it by simply the path '.'. Tables created with CREATE TEMPORARY TABLE we place in the temp dir of the mysqld server. @return DB_SUCCESS or error code */ UNIV_INTERN ulint fil_create_new_single_table_tablespace( /*===================================*/ ulint space_id, /*!< in: space id */ const char* tablename, /*!< in: the table name in the usual databasename/tablename format of InnoDB, or a dir path to a temp table */ ibool is_temp, /*!< in: TRUE if a table created with CREATE TEMPORARY TABLE */ ulint flags, /*!< in: tablespace flags */ ulint size); /*!< in: the initial size of the tablespace file in pages, must be >= FIL_IBD_FILE_INITIAL_SIZE */ #ifndef UNIV_HOTBACKUP /********************************************************************//** Tries to open a single-table tablespace and optionally checks the space id is right in it. If does not succeed, prints an error message to the .err log. This function is used to open a tablespace when we start up mysqld, and also in IMPORT TABLESPACE. NOTE that we assume this operation is used either at the database startup or under the protection of the dictionary mutex, so that two users cannot race here. This operation does not leave the file associated with the tablespace open, but closes it after we have looked at the space id in it. @return TRUE if success */ UNIV_INTERN ibool fil_open_single_table_tablespace( /*=============================*/ ibool check_space_id, /*!< in: should we check that the space id in the file is right; we assume that this function runs much faster if no check is made, since accessing the file inode probably is much faster (the OS caches them) than accessing the first page of the file */ ulint id, /*!< in: space id */ ulint flags, /*!< in: tablespace flags */ const char* name); /*!< in: table name in the databasename/tablename format */ /********************************************************************//** It is possible, though very improbable, that the lsn's in the tablespace to be imported have risen above the current system lsn, if a lengthy purge, ibuf merge, or rollback was performed on a backup taken with ibbackup. If that is the case, reset page lsn's in the file. We assume that mysqld was shut down after it performed these cleanup operations on the .ibd file, so that it at the shutdown stamped the latest lsn to the FIL_PAGE_FILE_FLUSH_LSN in the first page of the .ibd file, and we can determine whether we need to reset the lsn's just by looking at that flush lsn. @return TRUE if success */ UNIV_INTERN ibool fil_reset_too_high_lsns( /*====================*/ const char* name, /*!< in: table name in the databasename/tablename format */ ib_uint64_t current_lsn); /*!< in: reset lsn's if the lsn stamped to FIL_PAGE_FILE_FLUSH_LSN in the first page is too high */ #endif /* !UNIV_HOTBACKUP */ /********************************************************************//** At the server startup, if we need crash recovery, scans the database directories under the MySQL datadir, looking for .ibd files. Those files are single-table tablespaces. We need to know the space id in each of them so that we know into which file we should look to check the contents of a page stored in the doublewrite buffer, also to know where to apply log records where the space id is != 0. @return DB_SUCCESS or error number */ UNIV_INTERN ulint fil_load_single_table_tablespaces(void); /*===================================*/ /********************************************************************//** If we need crash recovery, and we have called fil_load_single_table_tablespaces() and dict_load_single_table_tablespaces(), we can call this function to print an error message of orphaned .ibd files for which there is not a data dictionary entry with a matching table name and space id. */ UNIV_INTERN void fil_print_orphaned_tablespaces(void); /*================================*/ /*******************************************************************//** Returns TRUE if a single-table tablespace does not exist in the memory cache, or is being deleted there. @return TRUE if does not exist or is being\ deleted */ UNIV_INTERN ibool fil_tablespace_deleted_or_being_deleted_in_mem( /*===========================================*/ ulint id, /*!< in: space id */ ib_int64_t version);/*!< in: tablespace_version should be this; if you pass -1 as the value of this, then this parameter is ignored */ /*******************************************************************//** Returns TRUE if a single-table tablespace exists in the memory cache. @return TRUE if exists */ UNIV_INTERN ibool fil_tablespace_exists_in_mem( /*=========================*/ ulint id); /*!< in: space id */ #ifndef UNIV_HOTBACKUP /*******************************************************************//** Returns TRUE if a matching tablespace exists in the InnoDB tablespace memory cache. Note that if we have not done a crash recovery at the database startup, there may be many tablespaces which are not yet in the memory cache. @return TRUE if a matching tablespace exists in the memory cache */ UNIV_INTERN ibool fil_space_for_table_exists_in_mem( /*==============================*/ ulint id, /*!< in: space id */ const char* name, /*!< in: table name in the standard 'databasename/tablename' format or the dir path to a temp table */ ibool is_temp, /*!< in: TRUE if created with CREATE TEMPORARY TABLE */ ibool mark_space, /*!< in: in crash recovery, at database startup we mark all spaces which have an associated table in the InnoDB data dictionary, so that we can print a warning about orphaned tablespaces */ ibool print_error_if_does_not_exist); /*!< in: print detailed error information to the .err log if a matching tablespace is not found from memory */ #else /* !UNIV_HOTBACKUP */ /********************************************************************//** Extends all tablespaces to the size stored in the space header. During the ibbackup --apply-log phase we extended the spaces on-demand so that log records could be appllied, but that may have left spaces still too small compared to the size stored in the space header. */ UNIV_INTERN void fil_extend_tablespaces_to_stored_len(void); /*======================================*/ #endif /* !UNIV_HOTBACKUP */ /**********************************************************************//** Tries to extend a data file so that it would accommodate the number of pages given. The tablespace must be cached in the memory cache. If the space is big enough already, does nothing. @return TRUE if success */ UNIV_INTERN ibool fil_extend_space_to_desired_size( /*=============================*/ ulint* actual_size, /*!< out: size of the space after extension; if we ran out of disk space this may be lower than the desired size */ ulint space_id, /*!< in: space id */ ulint size_after_extend);/*!< in: desired size in pages after the extension; if the current space size is bigger than this already, the function does nothing */ /*******************************************************************//** Tries to reserve free extents in a file space. @return TRUE if succeed */ UNIV_INTERN ibool fil_space_reserve_free_extents( /*===========================*/ ulint id, /*!< in: space id */ ulint n_free_now, /*!< in: number of free extents now */ ulint n_to_reserve); /*!< in: how many one wants to reserve */ /*******************************************************************//** Releases free extents in a file space. */ UNIV_INTERN void fil_space_release_free_extents( /*===========================*/ ulint id, /*!< in: space id */ ulint n_reserved); /*!< in: how many one reserved */ /*******************************************************************//** Gets the number of reserved extents. If the database is silent, this number should be zero. */ UNIV_INTERN ulint fil_space_get_n_reserved_extents( /*=============================*/ ulint id); /*!< in: space id */ /********************************************************************//** Reads or writes data. This operation is asynchronous (aio). @return DB_SUCCESS, or DB_TABLESPACE_DELETED if we are trying to do i/o on a tablespace which does not exist */ UNIV_INTERN ulint fil_io( /*===*/ ulint type, /*!< in: OS_FILE_READ or OS_FILE_WRITE, ORed to OS_FILE_LOG, if a log i/o and ORed to OS_AIO_SIMULATED_WAKE_LATER if simulated aio and we want to post a batch of i/os; NOTE that a simulated batch may introduce hidden chances of deadlocks, because i/os are not actually handled until all have been posted: use with great caution! */ ibool sync, /*!< in: TRUE if synchronous aio is desired */ ulint space_id, /*!< in: space id */ ulint zip_size, /*!< in: compressed page size in bytes; 0 for uncompressed pages */ ulint block_offset, /*!< in: offset in number of blocks */ ulint byte_offset, /*!< in: remainder of offset in bytes; in aio this must be divisible by the OS block size */ ulint len, /*!< in: how many bytes to read or write; this must not cross a file boundary; in aio this must be a block size multiple */ void* buf, /*!< in/out: buffer where to store read data or from where to write; in aio this must be appropriately aligned */ void* message); /*!< in: message for aio handler if non-sync aio used, else ignored */ /**********************************************************************//** Waits for an aio operation to complete. This function is used to write the handler for completed requests. The aio array of pending requests is divided into segments (see os0file.c for more info). The thread specifies which segment it wants to wait for. */ UNIV_INTERN void fil_aio_wait( /*=========*/ ulint segment); /*!< in: the number of the segment in the aio array to wait for */ /**********************************************************************//** Flushes to disk possible writes cached by the OS. If the space does not exist or is being dropped, does not do anything. */ UNIV_INTERN void fil_flush( /*======*/ ulint space_id); /*!< in: file space id (this can be a group of log files or a tablespace of the database) */ /**********************************************************************//** Flushes to disk writes in file spaces of the given type possibly cached by the OS. */ UNIV_INTERN void fil_flush_file_spaces( /*==================*/ ulint purpose); /*!< in: FIL_TABLESPACE, FIL_LOG */ /******************************************************************//** Checks the consistency of the tablespace cache. @return TRUE if ok */ UNIV_INTERN ibool fil_validate(void); /*==============*/ /********************************************************************//** Returns TRUE if file address is undefined. @return TRUE if undefined */ UNIV_INTERN ibool fil_addr_is_null( /*=============*/ fil_addr_t addr); /*!< in: address */ /********************************************************************//** Get the predecessor of a file page. @return FIL_PAGE_PREV */ UNIV_INTERN ulint fil_page_get_prev( /*==============*/ const byte* page); /*!< in: file page */ /********************************************************************//** Get the successor of a file page. @return FIL_PAGE_NEXT */ UNIV_INTERN ulint fil_page_get_next( /*==============*/ const byte* page); /*!< in: file page */ /*********************************************************************//** Sets the file page type. */ UNIV_INTERN void fil_page_set_type( /*==============*/ byte* page, /*!< in/out: file page */ ulint type); /*!< in: type */ /*********************************************************************//** Gets the file page type. @return type; NOTE that if the type has not been written to page, the return value not defined */ UNIV_INTERN ulint fil_page_get_type( /*==============*/ const byte* page); /*!< in: file page */ typedef struct fil_space_struct fil_space_t; #endif