typedef    struct fil_space_struct    fil_space_t;

/** Tablespace or log data space: let us call them by a common name space */
struct fil_space_struct {
    char*        name;    /*!< space name = the path to the first file in
                it */
    ulint        id;    /*!< space id */
    ib_int64_t    tablespace_version;
                /*!< in DISCARD/IMPORT this timestamp
                is used to check if we should ignore
                an insert buffer merge request for a
                page because it actually was for the
                previous incarnation of the space */
    ibool        mark;    /*!< this is set to TRUE at database startup if
                the space corresponds to a table in the InnoDB
                data dictionary; so we can print a warning of
                orphaned tablespaces */
    ibool        stop_ios;/*!< TRUE if we want to rename the
                .ibd file of tablespace and want to
                stop temporarily posting of new i/o
                requests on the file */
    ibool        stop_new_ops;
                /*!< we set this TRUE when we start
                deleting a single-table tablespace.
                When this is set following new ops
                are not allowed:
                * read IO request
                * ibuf merge
                * file flush
                Note that we can still possibly have
                new write operations because we don't
                check this flag when doing flush
                batches. */
    ulint        purpose;/*!< FIL_TABLESPACE, FIL_LOG, or
                FIL_ARCH_LOG */
    UT_LIST_BASE_NODE_T(fil_node_t) chain;
                /*!< base node for the file chain */
    ulint        size;    /*!< space size in pages; 0 if a single-table
                tablespace whose size we do not know yet;
                last incomplete megabytes in data files may be
                ignored if space == 0 */
    ulint        flags;    /*!< compressed page size and file format, or 0 */
    ulint        n_reserved_extents;
                /*!< number of reserved free extents for
                ongoing operations like B-tree page split */
    ulint        n_pending_flushes; /*!< this is positive when flushing
                the tablespace to disk; dropping of the
                tablespace is forbidden if this is positive */
    ulint        n_pending_ops;/*!< this is positive when we
                have pending operations against this
                tablespace. The pending operations can
                be ibuf merges or lock validation code
                trying to read a block.
                Dropping of the tablespace is forbidden
                if this is positive */
    hash_node_t    hash;    /*!< hash chain node */
    hash_node_t    name_hash;/*!< hash chain the name_hash table */
#ifndef UNIV_HOTBACKUP
    rw_lock_t    latch;    /*!< latch protecting the file space storage
                allocation */
#endif /* !UNIV_HOTBACKUP */
    UT_LIST_NODE_T(fil_space_t) unflushed_spaces;
                /*!< list of spaces with at least one unflushed
                file we have written to */
    ibool        is_in_unflushed_spaces; /*!< TRUE if this space is
                currently in unflushed_spaces */
    UT_LIST_NODE_T(fil_space_t) space_list;
                /*!< list of all spaces */
    ulint        magic_n;/*!< FIL_SPACE_MAGIC_N */
};