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/*-------------------------------------------------------------------------
*
* hash_xlog.h
* header file for Postgres hash AM implementation
*
*
* Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/access/hash_xlog.h
*
*-------------------------------------------------------------------------
*/
#ifndef HASH_XLOG_H
#define HASH_XLOG_H
#include "access/xlogreader.h"
#include "lib/stringinfo.h"
#include "storage/off.h"
/* Number of buffers required for XLOG_HASH_SQUEEZE_PAGE operation */
#define HASH_XLOG_FREE_OVFL_BUFS 6
/*
* XLOG records for hash operations
*/
#define XLOG_HASH_INIT_META_PAGE 0x00 /* initialize the meta page */
#define XLOG_HASH_INIT_BITMAP_PAGE 0x10 /* initialize the bitmap page */
#define XLOG_HASH_INSERT 0x20 /* add index tuple without split */
#define XLOG_HASH_ADD_OVFL_PAGE 0x30 /* add overflow page */
#define XLOG_HASH_SPLIT_ALLOCATE_PAGE 0x40 /* allocate new page for split */
#define XLOG_HASH_SPLIT_PAGE 0x50 /* split page */
#define XLOG_HASH_SPLIT_COMPLETE 0x60 /* completion of split operation */
#define XLOG_HASH_MOVE_PAGE_CONTENTS 0x70 /* remove tuples from one page
* and add to another page */
#define XLOG_HASH_SQUEEZE_PAGE 0x80 /* add tuples to one of the previous
* pages in chain and free the ovfl
* page */
#define XLOG_HASH_DELETE 0x90 /* delete index tuples from a page */
#define XLOG_HASH_SPLIT_CLEANUP 0xA0 /* clear split-cleanup flag in primary
* bucket page after deleting tuples
* that are moved due to split */
#define XLOG_HASH_UPDATE_META_PAGE 0xB0 /* update meta page after vacuum */
#define XLOG_HASH_VACUUM_ONE_PAGE 0xC0 /* remove dead tuples from index
* page */
/*
* xl_hash_split_allocate_page flag values, 8 bits are available.
*/
#define XLH_SPLIT_META_UPDATE_MASKS (1<<0)
#define XLH_SPLIT_META_UPDATE_SPLITPOINT (1<<1)
/*
* This is what we need to know about a HASH index create.
*
* Backup block 0: metapage
*/
typedef struct xl_hash_createidx
{
double num_tuples;
RegProcedure procid;
uint16 ffactor;
} xl_hash_createidx;
#define SizeOfHashCreateIdx (offsetof(xl_hash_createidx, ffactor) + sizeof(uint16))
/*
* This is what we need to know about simple (without split) insert.
*
* This data record is used for XLOG_HASH_INSERT
*
* Backup Blk 0: original page (data contains the inserted tuple)
* Backup Blk 1: metapage (HashMetaPageData)
*/
typedef struct xl_hash_insert
{
OffsetNumber offnum;
} xl_hash_insert;
#define SizeOfHashInsert (offsetof(xl_hash_insert, offnum) + sizeof(OffsetNumber))
/*
* This is what we need to know about addition of overflow page.
*
* This data record is used for XLOG_HASH_ADD_OVFL_PAGE
*
* Backup Blk 0: newly allocated overflow page
* Backup Blk 1: page before new overflow page in the bucket chain
* Backup Blk 2: bitmap page
* Backup Blk 3: new bitmap page
* Backup Blk 4: metapage
*/
typedef struct xl_hash_add_ovfl_page
{
uint16 bmsize;
bool bmpage_found;
} xl_hash_add_ovfl_page;
#define SizeOfHashAddOvflPage \
(offsetof(xl_hash_add_ovfl_page, bmpage_found) + sizeof(bool))
/*
* This is what we need to know about allocating a page for split.
*
* This data record is used for XLOG_HASH_SPLIT_ALLOCATE_PAGE
*
* Backup Blk 0: page for old bucket
* Backup Blk 1: page for new bucket
* Backup Blk 2: metapage
*/
typedef struct xl_hash_split_allocate_page
{
uint32 new_bucket;
uint16 old_bucket_flag;
uint16 new_bucket_flag;
uint8 flags;
} xl_hash_split_allocate_page;
#define SizeOfHashSplitAllocPage \
(offsetof(xl_hash_split_allocate_page, flags) + sizeof(uint8))
/*
* This is what we need to know about completing the split operation.
*
* This data record is used for XLOG_HASH_SPLIT_COMPLETE
*
* Backup Blk 0: page for old bucket
* Backup Blk 1: page for new bucket
*/
typedef struct xl_hash_split_complete
{
uint16 old_bucket_flag;
uint16 new_bucket_flag;
} xl_hash_split_complete;
#define SizeOfHashSplitComplete \
(offsetof(xl_hash_split_complete, new_bucket_flag) + sizeof(uint16))
/*
* This is what we need to know about move page contents required during
* squeeze operation.
*
* This data record is used for XLOG_HASH_MOVE_PAGE_CONTENTS
*
* Backup Blk 0: bucket page
* Backup Blk 1: page containing moved tuples
* Backup Blk 2: page from which tuples will be removed
*/
typedef struct xl_hash_move_page_contents
{
uint16 ntups;
bool is_prim_bucket_same_wrt; /* true if the page to which
* tuples are moved is same as
* primary bucket page */
} xl_hash_move_page_contents;
#define SizeOfHashMovePageContents \
(offsetof(xl_hash_move_page_contents, is_prim_bucket_same_wrt) + sizeof(bool))
/*
* This is what we need to know about the squeeze page operation.
*
* This data record is used for XLOG_HASH_SQUEEZE_PAGE
*
* Backup Blk 0: page containing tuples moved from freed overflow page
* Backup Blk 1: freed overflow page
* Backup Blk 2: page previous to the freed overflow page
* Backup Blk 3: page next to the freed overflow page
* Backup Blk 4: bitmap page containing info of freed overflow page
* Backup Blk 5: meta page
*/
typedef struct xl_hash_squeeze_page
{
BlockNumber prevblkno;
BlockNumber nextblkno;
uint16 ntups;
bool is_prim_bucket_same_wrt; /* true if the page to which
* tuples are moved is same as
* primary bucket page */
bool is_prev_bucket_same_wrt; /* true if the page to which
* tuples are moved is the page
* previous to the freed overflow
* page */
} xl_hash_squeeze_page;
#define SizeOfHashSqueezePage \
(offsetof(xl_hash_squeeze_page, is_prev_bucket_same_wrt) + sizeof(bool))
/*
* This is what we need to know about the deletion of index tuples from a page.
*
* This data record is used for XLOG_HASH_DELETE
*
* Backup Blk 0: primary bucket page
* Backup Blk 1: page from which tuples are deleted
*/
typedef struct xl_hash_delete
{
bool clear_dead_marking; /* true if this operation clears
* LH_PAGE_HAS_DEAD_TUPLES flag */
bool is_primary_bucket_page; /* true if the operation is for
* primary bucket page */
} xl_hash_delete;
#define SizeOfHashDelete (offsetof(xl_hash_delete, is_primary_bucket_page) + sizeof(bool))
/*
* This is what we need for metapage update operation.
*
* This data record is used for XLOG_HASH_UPDATE_META_PAGE
*
* Backup Blk 0: meta page
*/
typedef struct xl_hash_update_meta_page
{
double ntuples;
} xl_hash_update_meta_page;
#define SizeOfHashUpdateMetaPage \
(offsetof(xl_hash_update_meta_page, ntuples) + sizeof(double))
/*
* This is what we need to initialize metapage.
*
* This data record is used for XLOG_HASH_INIT_META_PAGE
*
* Backup Blk 0: meta page
*/
typedef struct xl_hash_init_meta_page
{
double num_tuples;
RegProcedure procid;
uint16 ffactor;
} xl_hash_init_meta_page;
#define SizeOfHashInitMetaPage \
(offsetof(xl_hash_init_meta_page, ffactor) + sizeof(uint16))
/*
* This is what we need to initialize bitmap page.
*
* This data record is used for XLOG_HASH_INIT_BITMAP_PAGE
*
* Backup Blk 0: bitmap page
* Backup Blk 1: meta page
*/
typedef struct xl_hash_init_bitmap_page
{
uint16 bmsize;
} xl_hash_init_bitmap_page;
#define SizeOfHashInitBitmapPage \
(offsetof(xl_hash_init_bitmap_page, bmsize) + sizeof(uint16))
/*
* This is what we need for index tuple deletion and to
* update the meta page.
*
* This data record is used for XLOG_HASH_VACUUM_ONE_PAGE
*
* Backup Blk 0: bucket page
* Backup Blk 1: meta page
*/
typedef struct xl_hash_vacuum_one_page
{
RelFileNode hnode;
int ntuples;
/* TARGET OFFSET NUMBERS FOLLOW AT THE END */
} xl_hash_vacuum_one_page;
#define SizeOfHashVacuumOnePage \
(offsetof(xl_hash_vacuum_one_page, ntuples) + sizeof(int))
extern void hash_redo(XLogReaderState *record);
extern void hash_desc(StringInfo buf, XLogReaderState *record);
extern const char *hash_identify(uint8 info);
extern void hash_mask(char *pagedata, BlockNumber blkno);
#endif /* HASH_XLOG_H */
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