Adding Libgfdb to GlusterFS

*************************************************************************
			Libgfdb						|
*************************************************************************
Libgfdb provides abstract mechanism to record extra/rich metadata
required for data maintenance, such as data tiering/classification.
It provides consumer with API for recording and querying, keeping
the consumer abstracted from the data store used beneath for storing data.
It works in a plug-and-play model, where data stores can be plugged-in.
Presently we have plugin for Sqlite3. In the future will provide recording
and querying performance optimizer. In the current implementation the schema
of metadata is fixed.

Schema:
~~~~~~
      GF_FILE_TB Table:
      ~~~~~~~~~~~~~~~~~
      This table has one entry per file inode. It holds the metadata required to
      make decisions in data maintenance.
      GF_ID (Primary key)	: File GFID (Universal Unique IDentifier in the namespace)
      W_SEC, W_MSEC 		: Write wind time in sec & micro-sec
      UW_SEC, UW_MSEC		: Write un-wind time in sec & micro-sec
      W_READ_SEC, W_READ_MSEC 	: Read wind time in sec & micro-sec
      UW_READ_SEC, UW_READ_MSEC : Read un-wind time in sec & micro-sec
      WRITE_FREQ_CNTR INTEGER	: Write Frequency Counter
      READ_FREQ_CNTR INTEGER	: Read Frequency Counter

      GF_FLINK_TABLE:
      ~~~~~~~~~~~~~~
      This table has all the hardlinks to a file inode.
      GF_ID		: File GFID               (Composite Primary Key)``|
      GF_PID		: Parent Directory GFID  (Composite Primary Key)   |-> Primary Key
      FNAME 		: File Base Name          (Composite Primary Key)__|
      FPATH 		: File Full Path (Its redundant for now, this will go)
      W_DEL_FLAG 	: This Flag is used for crash consistancy, when a link is unlinked.
                  	  i.e Set to 1 during unlink wind and during unwind this record
                          is deleted
      LINK_UPDATE 	: This Flag is used when a link is changed i.e rename.
                          Set to 1 when rename wind and set to 0 in rename unwind

Libgfdb API:
~~~~~~~~~~~
Refer libglusterfs/src/gfdb/gfdb_data_store.h

Change-Id: I2e9fbab3878ce630a7f41221ef61017dc43db11f
BUG: 1194753
Signed-off-by: Joseph Fernandes <josferna@redhat.com>
Signed-off-by: Dan Lambright <dlambrig@redhat.com>
Signed-off-by: Joseph Fernandes <josferna@redhat.com>
Reviewed-on: http://review.gluster.org/9683
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 219 insertions, 0 deletions

diff --git a/libglusterfs/src/gfdb/gfdb_data_store.h b/libglusterfs/src/gfdb/gfdb_data_store.h
new file mode 100644
index 00000000000..1212c2b3fe1
--- /dev/null
+++ b/libglusterfs/src/gfdb/gfdb_data_store.h
@@ -0,0 +1,219 @@
+/*
+   Copyright (c) 2015 Red Hat, Inc. <http://www.redhat.com>
+   This file is part of GlusterFS.
+
+   This file is licensed to you under your choice of the GNU Lesser
+   General Public License, version 3 or any later version (LGPLv3 or
+   later), or the GNU General Public License, version 2 (GPLv2), in all
+   cases as published by the Free Software Foundation.
+*/
+#ifndef __GFDB_DATA_STORE_H
+#define __GFDB_DATA_STORE_H
+
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "glusterfs.h"
+#include "xlator.h"
+#include "logging.h"
+#include "common-utils.h"
+#include <time.h>
+#include <sys/time.h>
+
+#include "gfdb_data_store_types.h"
+#include "gfdb_sqlite3.h"
+
+
+/* GFDB Connection Node:
+ * ~~~~~~~~~~~~~~~~~~~~
+ * Represents the connection to the database while using libgfdb
+ * The connection node is not thread safe as far as fini_db is concerned.
+ * You can use a single connection node
+ * to do multithreaded db operations like insert/delete/find of records.
+ * But you need to wait for all the operating threads to complete i.e
+ * pthread_join() and then do fini_db() to kill the connection node.
+ * gfdb_conn_node_t is an opaque structure.
+ * */
+typedef struct gfdb_conn_node_t gfdb_conn_node_t;
+
+
+
+
+/*Libgfdb API Function: Used to initialize db connection
+ * Arguments:
+ *      args         :  Dictionary containing database specific parameters
+ *                      eg: For sqlite3, pagesize, cachesize, db name, db path
+                        etc
+ *      gfdb_db_type :  Type of data base used i.e sqlite or hyperdex etc
+ * Returns : if successful return the GFDB Connection Node to the caller or
+ *          NULL value in case of failure*/
+gfdb_conn_node_t *
+init_db(dict_t *arg, gfdb_db_type_t db_type);
+
+
+
+
+
+/*Libgfdb API Function: Used to terminate/de-initialize db connection
+ *                      (Destructor function for db connection object)
+ * Arguments:
+ *      _conn_node  :  DB Connection Index of the DB Connection
+ * Returns : if successful return 0 or
+ *          -ve value in case of failure*/
+int
+fini_db(gfdb_conn_node_t *);
+
+
+
+
+/*Libgfdb API Function: Used to insert/updated records in the database
+ *                      NOTE: In current gfdb_sqlite plugin we use that
+ *                      same function to delete the record. Set the
+ *                      gfdb_fop_path to GFDB_FOP_UNDEL to delete the
+ *                      link of inode from GF_FLINK_TB and
+ *                      GFDB_FOP_UNDEL_ALL to delete all the records from
+ *                      GF_FLINK_TB and GF_FILE_TB.
+ *                      TODO: Should seperate this function into the
+ *                      delete_record function
+ *                      Refer CTR Xlator features/changetimerecorder for usage
+ * Arguments:
+ *      _conn_node     :  GFDB Connection node
+ *      gfdb_db_record :  Record to be inserted/updated
+ * Returns : if successful return 0 or
+ *          -ve value in case of failure*/
+int
+insert_record(gfdb_conn_node_t *, gfdb_db_record_t *gfdb_db_record);
+
+
+
+
+/*Libgfdb API Function: Used to delete record from the database
+ *                      NOTE: In the current gfdb_sqlite3 plugin
+ *                      implementation this function is dummy.
+ *                      Use the insert_record function.
+ *                      Refer CTR Xlator features/changetimerecorder for usage
+ * Arguments:
+ *      _conn_node     :  GFDB Connection node
+ *      gfdb_db_record :  Record to be deleted
+ * Returns : if successful return 0 or
+ *          -ve value in case of failure*/
+int
+delete_record(gfdb_conn_node_t *, gfdb_db_record_t *gfdb_db_record);
+
+
+
+
+
+/*Libgfdb API Function: Query all the records from the database
+ * Arguments:
+ *      _conn_node      : GFDB Connection node
+ *      query_callback  : Call back function that will be called
+ *                        for every record found
+ *      _query_cbk_args : Custom argument passed for the call back
+ *                        function query_callback
+ * Returns : if successful return 0 or
+ *          -ve value in case of failure*/
+int find_all(gfdb_conn_node_t *, gf_query_callback_t query_callback,
+                void *_query_cbk_args);
+
+
+
+
+
+/*Libgfdb API Function: Query records/files that have not changed/accessed
+ *                      from a time in past to current time
+ * Arguments:
+ *      _conn_node              : GFDB Connection node
+ *      query_callback          : Call back function that will be called
+ *                                for every record found
+ *      _query_cbk_args         : Custom argument passed for the call back
+ *                                function query_callback
+ *      for_time                : Time from where the file/s are not
+ *                                changed/accessed
+ * Returns : if successful return 0 or
+ *          -ve value in case of failure*/
+int find_unchanged_for_time(gfdb_conn_node_t *,
+                        gf_query_callback_t query_callback,
+                        void *_query_cbk_args, gfdb_time_t *for_time);
+
+
+
+
+/*Libgfdb API Function: Query records/files that have changed/accessed from a
+ *                      time in past to current time
+ * Arguments:
+ *      _conn_node              : GFDB Connection node
+ *      query_callback          : Call back function that will be called
+ *                                for every record found
+ *      _query_cbk_args         : Custom argument passed for the call back
+ *                                function query_callback
+ *      for_time                : Time from where the file/s are
+ *                                changed/accessed
+ * Returns : if successful return 0 or
+ *          -ve value in case of failure*/
+int find_recently_changed_files(gfdb_conn_node_t *_conn,
+                gf_query_callback_t query_callback, void *_query_cbk_args,
+                gfdb_time_t *from_time);
+
+
+
+
+
+/*Libgfdb API Function: Query records/files that have not changed/accessed
+ *                      from a time in past to current time, with
+ *                      a desired frequency
+ * Arguments:
+ *      _conn_node              : GFDB Connection node
+ *      query_callback          : Call back function that will be called
+ *                                for every record found
+ *      _query_cbk_args         : Custom argument passed for the call back
+ *                                function query_callback
+ *      for_time                : Time from where the file/s are not
+ *                                changed/accessed
+ *      write_freq_thresold     : Desired Write Frequency lower limit
+ *      read_freq_thresold      : Desired Read Frequency lower limit
+ *      _clear_counters         : If true, Clears all the frequency counters of
+ *                                all files.
+ * Returns : if successful return 0 or
+ *          -ve value in case of failure*/
+int find_unchanged_for_time_freq(gfdb_conn_node_t *_conn,
+                                        gf_query_callback_t query_callback,
+                                        void *_query_cbk_args,
+                                        gfdb_time_t *for_time,
+                                        int write_freq_thresold,
+                                        int read_freq_thresold,
+                                        gf_boolean_t _clear_counters);
+
+
+
+
+
+/*Libgfdb API Function: Query records/files that have changed/accessed from a
+ *                      time in past to current time, with
+ *                      a desired frequency
+ * Arguments:
+ *      _conn_node              : GFDB Connection node
+ *      query_callback          : Call back function that will be called
+ *                                for every record found
+ *      _query_cbk_args         : Custom argument passed for the call back
+ *                                function query_callback
+ *      for_time                : Time from where the file/s are
+ *                                changed/accessed
+ *      write_freq_thresold     : Desired Write Frequency lower limit
+ *      read_freq_thresold      : Desired Read Frequency lower limit
+ *      _clear_counters         : If true, Clears all the frequency counters of
+ *                                all files.
+ * Returns : if successful return 0 or
+ *          -ve value in case of failure*/
+int find_recently_changed_files_freq(gfdb_conn_node_t *_conn,
+                                gf_query_callback_t query_callback,
+                                void *_query_cbk_args,
+                                gfdb_time_t *from_time,
+                                int write_freq_thresold,
+                                int read_freq_thresold,
+                                gf_boolean_t _clear_counters);
+
+#endif