(*
Copyright 2010 Gerd Stolpmann
This file is part of Plasma, a distributed filesystem and a
map/reduce computation framework. Unless you have a written license
agreement with the copyright holder (Gerd Stolpmann), the following
terms apply:
Plasma 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, either version 3 of the License, or
(at your option) any later version.
Plasma 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 Foobar. If not, see <http://www.gnu.org/licenses/>.
*)
(* $Id: nn_db.mli 271 2010-10-20 00:09:51Z gerd $ *)
(** Namenode access routines to database *)
class type ro_transaction =
object
method connection : Pfs_db.ro_async_connection
(** The connection. This method fails if the transaction is already done *)
method event_system : Unixqueue.event_system
(** The event system this transaction uses *)
method return : unit -> unit
(** return the transaction to the pool *)
end
class type transaction =
object
method connection : Pfs_db.rw_async_connection
(** The connection. This method fails if the transaction is already done *)
method ro_connection : Pfs_db.ro_async_connection
(** The same connection coerced to read-only *)
method event_system : Unixqueue.event_system
(** The event system this transaction uses *)
method prepare : unit -> unit Uq_engines.engine
(** Prepares the transaction for commit *)
method commit : unit -> unit Uq_engines.engine
(** Commits the transaction (prepared or not), and returns *)
method rollback : unit -> unit Uq_engines.engine
(** Rolls the transaction back, and returns *)
method return : unit -> unit
(** return the transaction to the pool or closes it *)
end
type inodeinfo = Pfs_rpcapi_aux.inodeinfo
val init : Pfs_db.db_config -> Unixqueue.event_system -> unit
(** The esys is used for ro transactions *)
val ro_esys : unit -> Unixqueue.event_system
(** Returns the esys for ro transactions *)
val commit_all_prepared_transactions : unit -> unit
(** Commits all prepared transactions at system startup *)
val transact : Unixqueue.event_system -> transaction
(** Finds an unused connection, and start a transaction *)
val ro_transact : unit -> ro_transaction Uq_engines.engine
(** Same for read-only transactions. Note that this is an engine: If the
number of connections has reached the limit, it is waited until an
existing connection becomes unused.
*)
val with_ro_trans : (Pfs_db.ro_async_connection ->
Unixqueue.event_system -> 'a Uq_engines.engine) ->
'a Uq_engines.engine
(** [with_ro_trans f]: Runs [e = f conn esys] for a shared read-only
transaction and returns [e]
*)
val datastore_list_e : Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
Nn_datastores.datastore list Uq_engines.engine
(** Gets a list of all datastores *)
val datastore_list_ro_e : unit ->
Nn_datastores.datastore list Uq_engines.engine
(** same, using an ro transaction *)
val datastore_find_e : identity:string ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
Nn_datastores.datastore option Uq_engines.engine
(** Find a datastore by identity *)
val datastore_find_ro_e : identity:string ->
Nn_datastores.datastore option Uq_engines.engine
(** same, using an ro transaction *)
val datastore_upd_e : id:int ->
identity:string ->
size:int64 ->
enabled:bool ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Updates the datastore table. If the record is new, it is added.
The blockalloc table is updated, too: For new stores, the
rows are added. If the size of the existing store is increased,
further rows are added.
It is an error to decrease the size.
*)
val datastore_del_e : id:int ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Deletes the datastore with this ID and all rows referencing it *)
val revision_get_e : Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
string Uq_engines.engine
(** Get the revision string *)
val revision_get_ro_e : unit -> string Uq_engines.engine
(** same, using an ro transaction *)
val revision_upd_e : revstr:string ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Updates the revision string *)
val blockalloc_list_e : datastore:int ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
(int64 * string) list Uq_engines.engine
(** Reads the blockalloc table for this [datastore] ID. Returns the table
as pairs [(blkidx,blkmap)]
*)
val blockalloc_list_ro_e : datastore:int ->
(int64 * string) list Uq_engines.engine
(** same, using an ro transaction *)
val blockalloc_upd_e : datastore:int ->
blkidx:int64 ->
blkmap:string ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Updates the [blockalloc] table *)
val inode_listall_e : Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
int64 list Uq_engines.engine
(** list all inode numbers *)
val inode_get_e : id:int64 ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
inodeinfo option Uq_engines.engine
(** Loads the inode data if existing *)
val inode_get_ro_e : id:int64 ->
inodeinfo option Uq_engines.engine
(** same, using an ro transaction *)
val inode_maxid_e : Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
int64 Uq_engines.engine
(** Returns the max ID *)
val inode_maxid_ro_e : unit -> int64 Uq_engines.engine
(** same, using an ro transaction *)
val inode_ins_e : id:int64 ->
inodeinfo ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Inserts a new row into [inode] *)
val inode_upd_e : id:int64 ->
inodeinfo ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Updates a row in [inode]. [filetype] cannot be updated, and changes are
silently ignored.
*)
val inode_upd_time_e : id:int64 ->
mtime:Pfs_rpcapi_aux.time option ->
ctime:Pfs_rpcapi_aux.time option ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Sets the mtime and/or ctime. It is not an error if the inodes does
not exist anymore.
*)
val inode_del_e : id:int64 ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Deletes a row from [inode] *)
val inodeblocks_get_e : inode:int64 ->
blkidx:int64 ->
len:int64 ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
Pfs_rpcapi_aux.blockinfo list Uq_engines.engine
(** Gets the block information for [inode] in the range from index
[blkidx] to [blkidx+len-1].
*)
val inodeblocks_get_ro_e : inode:int64 ->
blkidx:int64 ->
len:int64 ->
Pfs_rpcapi_aux.blockinfo list Uq_engines.engine
(** same, using an ro transaction *)
val inodeblocks_getall_e : inode:int64 ->
dsid:int ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
(int64 * int64) list Uq_engines.engine
(** Returns list of [(blkidx,block)] for this [inode] and this datastore
[dsid] (for fsck)
*)
val inodeblocks_del_e : inode:int64 ->
blkidx:int64 ->
len:int64 ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Delete the blocks for [inode] in the range from index
[blkidx] to [blkidx+len-1].
*)
val inodeblocks_ins_e : inode:int64 ->
Pfs_rpcapi_aux.blockinfo list ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Insert these blocks *)
val names_get_e : dir_inode:int64 ->
name:string ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
int64 option Uq_engines.engine
(** Look up inode by dir_inode and name *)
val names_get_ro_e :
dir_inode:int64 -> name:string -> int64 option Uq_engines.engine
(** same, using an ro transaction *)
val names_rev_get_e : inode:int64 ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
(int64 * string) list Uq_engines.engine
(** Look up names by inode. The return values are the inode of the
directory and the member name. (No complete paths.)
*)
val names_rev_get_ro_e : inode:int64 -> (int64 * string) list Uq_engines.engine
(** same, using an ro transaction *)
val names_get_parent_e : inode:int64 ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
int64 option Uq_engines.engine
(** Look up the parent inode of an inode. This works only reliably for
directories - file inodes can have multiple parents, and in this
case [None] is returned.
*)
val names_get_parent_ro_e : inode:int64 -> int64 option Uq_engines.engine
(** same, using an ro transaction *)
val names_count_e : inode:int64 ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
int Uq_engines.engine
(** Count names of an inode *)
val names_count_ro_e : inode:int64 -> int Uq_engines.engine
(** same, using an ro transaction *)
val names_list_e : dir_inode:int64 ->
Pfs_db.ro_async_connection ->
Unixqueue.event_system ->
(string * int64) list Uq_engines.engine
(** Lists the contents of the directory identified by [dir_inode].
The contents are the member names and the inodes of the members.
*)
val names_list_ro_e : dir_inode:int64 -> (string * int64) list Uq_engines.engine
(** same, using an ro transaction *)
val names_ins_e : dir_inode:int64 -> name:string -> inode:int64 ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Insert this name to inode mapping *)
val names_del_e : dir_inode:int64 -> name:string ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Delete this name *)
(** {2 Two-phase commit support} *)
type modification =
[ `Datastore_upd of int * string * int64 * bool
| `Datastore_del of int
| `Revision_upd of string
| `Blockalloc_upd of int * int64 * string
| `Inode_ins of int64 * inodeinfo
| `Inode_upd of int64 * inodeinfo
| `Inode_upd_time of int64 * Pfs_rpcapi_aux.time option * Pfs_rpcapi_aux.time option
| `Inode_del of int64
| `Inodeblocks_ins of int64 * Pfs_rpcapi_aux.blockinfo list
| `Inodeblocks_del of int64 * int64 * int64
| `Names_ins of int64 * string * int64
| `Names_del of int64 * string
]
(** Database modification operations that are covered by the 2-phase
commit protocol. The names of the operations correspond to those
in {!Nn_db} and {!Nn_slave}.
*)
val exec_e : modification ->
Pfs_db.rw_async_connection ->
Unixqueue.event_system ->
unit Uq_engines.engine
(** Performs the passed modification *)
