xlogutils.h File Reference

#include "access/xlogreader.h"
#include "storage/bufmgr.h"

Include dependency graph for xlogutils.h:

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Go to the source code of this file.

Data Structures
struct	ReadLocalXLogPageNoWaitPrivate

Macros
#define	InHotStandby   (standbyState >= STANDBY_SNAPSHOT_PENDING)

Typedefs
typedef struct ReadLocalXLogPageNoWaitPrivate	ReadLocalXLogPageNoWaitPrivate

Enumerations
enum	HotStandbyState { STANDBY_DISABLED , STANDBY_INITIALIZED , STANDBY_SNAPSHOT_PENDING , STANDBY_SNAPSHOT_READY }
enum	XLogRedoAction { BLK_NEEDS_REDO , BLK_DONE , BLK_RESTORED , BLK_NOTFOUND }

Functions
bool	XLogHaveInvalidPages (void)
void	XLogCheckInvalidPages (void)
void	XLogDropRelation (RelFileLocator rlocator, ForkNumber forknum)
void	XLogDropDatabase (Oid dbid)
void	XLogTruncateRelation (RelFileLocator rlocator, ForkNumber forkNum, BlockNumber nblocks)
XLogRedoAction	XLogReadBufferForRedo (XLogReaderState *record, uint8 block_id, Buffer *buf)
Buffer	XLogInitBufferForRedo (XLogReaderState *record, uint8 block_id)
XLogRedoAction	XLogReadBufferForRedoExtended (XLogReaderState *record, uint8 block_id, ReadBufferMode mode, bool get_cleanup_lock, Buffer *buf)
Buffer	XLogReadBufferExtended (RelFileLocator rlocator, ForkNumber forknum, BlockNumber blkno, ReadBufferMode mode, Buffer recent_buffer)
Relation	CreateFakeRelcacheEntry (RelFileLocator rlocator)
void	FreeFakeRelcacheEntry (Relation fakerel)
int	read_local_xlog_page (XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, char *cur_page)
int	read_local_xlog_page_no_wait (XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, char *cur_page)
void	wal_segment_open (XLogReaderState *state, XLogSegNo nextSegNo, TimeLineID *tli_p)
void	wal_segment_close (XLogReaderState *state)
void	XLogReadDetermineTimeline (XLogReaderState *state, XLogRecPtr wantPage, uint32 wantLength, TimeLineID currTLI)
void	WALReadRaiseError (WALReadError *errinfo)

Variables
PGDLLIMPORT bool	InRecovery
PGDLLIMPORT HotStandbyState	standbyState

Macro Definition Documentation

InHotStandby

#define InHotStandby   (standbyState >= STANDBY_SNAPSHOT_PENDING)

Definition at line 57 of file xlogutils.h.

Typedef Documentation

ReadLocalXLogPageNoWaitPrivate

typedef struct ReadLocalXLogPageNoWaitPrivate ReadLocalXLogPageNoWaitPrivate

Enumeration Type Documentation

HotStandbyState

enum HotStandbyState

Enumerator
STANDBY_DISABLED
STANDBY_INITIALIZED
STANDBY_SNAPSHOT_PENDING
STANDBY_SNAPSHOT_READY

Definition at line 47 of file xlogutils.h.

{
    STANDBY_DISABLED,
    STANDBY_INITIALIZED,
    STANDBY_SNAPSHOT_PENDING,
    STANDBY_SNAPSHOT_READY
} HotStandbyState;

XLogRedoAction

enum XLogRedoAction

Enumerator
BLK_NEEDS_REDO
BLK_DONE
BLK_RESTORED
BLK_NOTFOUND

Definition at line 69 of file xlogutils.h.

{
    BLK_NEEDS_REDO,             /* changes from WAL record need to be applied */
    BLK_DONE,                   /* block is already up-to-date */
    BLK_RESTORED,               /* block was restored from a full-page image */
    BLK_NOTFOUND                /* block was not found (and hence does not
                                 * need to be replayed) */
} XLogRedoAction;

Function Documentation

CreateFakeRelcacheEntry()

Relation CreateFakeRelcacheEntry

(

RelFileLocator

rlocator

)

Definition at line 600 of file xlogutils.c.

{
    FakeRelCacheEntry fakeentry;
    Relation    rel;
 
    /* Allocate the Relation struct and all related space in one block. */
    fakeentry = palloc0(sizeof(FakeRelCacheEntryData));
    rel = (Relation) fakeentry;
 
    rel->rd_rel = &fakeentry->pgc;
    rel->rd_locator = rlocator;
 
    /*
     * We will never be working with temp rels during recovery or while
     * syncing WAL-skipped files.
     */
    rel->rd_backend = InvalidBackendId;
 
    /* It must be a permanent table here */
    rel->rd_rel->relpersistence = RELPERSISTENCE_PERMANENT;
 
    /* We don't know the name of the relation; use relfilenumber instead */
    sprintf(RelationGetRelationName(rel), "%u", rlocator.relNumber);
 
    /*
     * We set up the lockRelId in case anything tries to lock the dummy
     * relation.  Note that this is fairly bogus since relNumber may be
     * different from the relation's OID.  It shouldn't really matter though.
     * In recovery, we are running by ourselves and can't have any lock
     * conflicts.  While syncing, we already hold AccessExclusiveLock.
     */
    rel->rd_lockInfo.lockRelId.dbId = rlocator.dbOid;
    rel->rd_lockInfo.lockRelId.relId = rlocator.relNumber;
 
    rel->rd_smgr = NULL;
 
    return rel;
}

References LockRelId::dbId, RelFileLocator::dbOid, InvalidBackendId, LockInfoData::lockRelId, palloc0(), FakeRelCacheEntryData::pgc, RelationData::rd_backend, RelationData::rd_locator, RelationData::rd_lockInfo, RelationData::rd_rel, RelationData::rd_smgr, RelationGetRelationName, LockRelId::relId, RelFileLocator::relNumber, and sprintf.

Referenced by heap_xlog_delete(), heap_xlog_insert(), heap_xlog_lock(), heap_xlog_lock_updated(), heap_xlog_multi_insert(), heap_xlog_update(), heap_xlog_visible(), smgr_redo(), and smgrDoPendingSyncs().

FreeFakeRelcacheEntry()

void FreeFakeRelcacheEntry

(

Relation

fakerel

)

Definition at line 643 of file xlogutils.c.

{
    /* make sure the fakerel is not referenced by the SmgrRelation anymore */
    if (fakerel->rd_smgr != NULL)
        smgrclearowner(&fakerel->rd_smgr, fakerel->rd_smgr);
    pfree(fakerel);
}

References pfree(), RelationData::rd_smgr, and smgrclearowner().

Referenced by heap_xlog_delete(), heap_xlog_insert(), heap_xlog_lock(), heap_xlog_lock_updated(), heap_xlog_multi_insert(), heap_xlog_update(), heap_xlog_visible(), smgr_redo(), and smgrDoPendingSyncs().

read_local_xlog_page()

int read_local_xlog_page	(	XLogReaderState *	state,
		XLogRecPtr	targetPagePtr,
		int	reqLen,
		XLogRecPtr	targetRecPtr,
		char *	cur_page
	)

Definition at line 878 of file xlogutils.c.

{
    return read_local_xlog_page_guts(state, targetPagePtr, reqLen,
                                     targetRecPtr, cur_page, true);
}

References read_local_xlog_page_guts().

Referenced by create_logical_replication_slot(), pg_logical_replication_slot_advance(), pg_logical_slot_get_changes_guts(), and XlogReadTwoPhaseData().

read_local_xlog_page_no_wait()

int read_local_xlog_page_no_wait	(	XLogReaderState *	state,
		XLogRecPtr	targetPagePtr,
		int	reqLen,
		XLogRecPtr	targetRecPtr,
		char *	cur_page
	)

Definition at line 890 of file xlogutils.c.

{
    return read_local_xlog_page_guts(state, targetPagePtr, reqLen,
                                     targetRecPtr, cur_page, false);
}

References read_local_xlog_page_guts().

Referenced by InitXLogReaderState().

wal_segment_close()

void wal_segment_close

(

XLogReaderState *

state

)

Definition at line 859 of file xlogutils.c.

{
    close(state->seg.ws_file);
    /* need to check errno? */
    state->seg.ws_file = -1;
}

References close.

Referenced by create_logical_replication_slot(), CreateReplicationSlot(), InitWalRecovery(), InitXLogReaderState(), pg_logical_replication_slot_advance(), pg_logical_slot_get_changes_guts(), StartLogicalReplication(), StartReplication(), WalSndErrorCleanup(), XlogReadTwoPhaseData(), and XLogSendPhysical().

wal_segment_open()

void wal_segment_open	(	XLogReaderState *	state,
		XLogSegNo	nextSegNo,
		TimeLineID *	tli_p
	)

Definition at line 834 of file xlogutils.c.

{
    TimeLineID  tli = *tli_p;
    char        path[MAXPGPATH];
 
    XLogFilePath(path, tli, nextSegNo, state->segcxt.ws_segsize);
    state->seg.ws_file = BasicOpenFile(path, O_RDONLY | PG_BINARY);
    if (state->seg.ws_file >= 0)
        return;
 
    if (errno == ENOENT)
        ereport(ERROR,
                (errcode_for_file_access(),
                 errmsg("requested WAL segment %s has already been removed",
                        path)));
    else
        ereport(ERROR,
                (errcode_for_file_access(),
                 errmsg("could not open file \"%s\": %m",
                        path)));
}

References BasicOpenFile(), ereport, errcode_for_file_access(), errmsg(), ERROR, MAXPGPATH, PG_BINARY, and XLogFilePath().

Referenced by create_logical_replication_slot(), InitXLogReaderState(), pg_logical_replication_slot_advance(), pg_logical_slot_get_changes_guts(), and XlogReadTwoPhaseData().

WALReadRaiseError()

void WALReadRaiseError

(

WALReadError *

errinfo

)

Definition at line 1042 of file xlogutils.c.

{
    WALOpenSegment *seg = &errinfo->wre_seg;
    char        fname[MAXFNAMELEN];
 
    XLogFileName(fname, seg->ws_tli, seg->ws_segno, wal_segment_size);
 
    if (errinfo->wre_read < 0)
    {
        errno = errinfo->wre_errno;
        ereport(ERROR,
                (errcode_for_file_access(),
                 errmsg("could not read from WAL segment %s, offset %d: %m",
                        fname, errinfo->wre_off)));
    }
    else if (errinfo->wre_read == 0)
    {
        ereport(ERROR,
                (errcode(ERRCODE_DATA_CORRUPTED),
                 errmsg("could not read from WAL segment %s, offset %d: read %d of %d",
                        fname, errinfo->wre_off, errinfo->wre_read,
                        errinfo->wre_req)));
    }
}

References ereport, errcode(), ERRCODE_DATA_CORRUPTED, errcode_for_file_access(), errmsg(), ERROR, MAXFNAMELEN, wal_segment_size, WALReadError::wre_errno, WALReadError::wre_off, WALReadError::wre_read, WALReadError::wre_req, WALReadError::wre_seg, WALOpenSegment::ws_segno, WALOpenSegment::ws_tli, and XLogFileName().

Referenced by logical_read_xlog_page(), read_local_xlog_page_guts(), and XLogSendPhysical().

XLogCheckInvalidPages()

void XLogCheckInvalidPages

(

void

)

Definition at line 248 of file xlogutils.c.

{
    HASH_SEQ_STATUS status;
    xl_invalid_page *hentry;
    bool        foundone = false;
 
    if (invalid_page_tab == NULL)
        return;                 /* nothing to do */
 
    hash_seq_init(&status, invalid_page_tab);
 
    /*
     * Our strategy is to emit WARNING messages for all remaining entries and
     * only PANIC after we've dumped all the available info.
     */
    while ((hentry = (xl_invalid_page *) hash_seq_search(&status)) != NULL)
    {
        report_invalid_page(WARNING, hentry->key.locator, hentry->key.forkno,
                            hentry->key.blkno, hentry->present);
        foundone = true;
    }
 
    if (foundone)
        elog(ignore_invalid_pages ? WARNING : PANIC,
             "WAL contains references to invalid pages");
 
    hash_destroy(invalid_page_tab);
    invalid_page_tab = NULL;
}

References xl_invalid_page_key::blkno, elog(), xl_invalid_page_key::forkno, hash_destroy(), hash_seq_init(), hash_seq_search(), ignore_invalid_pages, invalid_page_tab, xl_invalid_page::key, xl_invalid_page_key::locator, PANIC, xl_invalid_page::present, report_invalid_page(), and WARNING.

Referenced by CheckRecoveryConsistency().

XLogDropDatabase()

void XLogDropDatabase

(

Oid

dbid

)

Definition at line 669 of file xlogutils.c.

{
    /*
     * This is unnecessarily heavy-handed, as it will close SMgrRelation
     * objects for other databases as well. DROP DATABASE occurs seldom enough
     * that it's not worth introducing a variant of smgrclose for just this
     * purpose. XXX: Or should we rather leave the smgr entries dangling?
     */
    smgrcloseall();
 
    forget_invalid_pages_db(dbid);
}

References forget_invalid_pages_db(), and smgrcloseall().

Referenced by dbase_redo().

XLogDropRelation()

void XLogDropRelation	(	RelFileLocator	rlocator,
		ForkNumber	forknum
	)

Definition at line 658 of file xlogutils.c.

{
    forget_invalid_pages(rlocator, forknum, 0);
}

References forget_invalid_pages().

Referenced by DropRelationFiles().

XLogHaveInvalidPages()

bool XLogHaveInvalidPages

(

void

)

Definition at line 238 of file xlogutils.c.

{
    if (invalid_page_tab != NULL &&
        hash_get_num_entries(invalid_page_tab) > 0)
        return true;
    return false;
}

References hash_get_num_entries(), and invalid_page_tab.

Referenced by RecoveryRestartPoint().

XLogInitBufferForRedo()

Buffer XLogInitBufferForRedo	(	XLogReaderState *	record,
		uint8	block_id
	)

Definition at line 329 of file xlogutils.c.

{
    Buffer      buf;
 
    XLogReadBufferForRedoExtended(record, block_id, RBM_ZERO_AND_LOCK, false,
                                  &buf);
    return buf;
}

References buf, RBM_ZERO_AND_LOCK, and XLogReadBufferForRedoExtended().

Referenced by _bt_restore_meta(), brin_xlog_createidx(), brin_xlog_insert_update(), brin_xlog_revmap_extend(), btree_xlog_mark_page_halfdead(), btree_xlog_newroot(), btree_xlog_split(), btree_xlog_unlink_page(), ginRedoCreatePTree(), ginRedoDeleteListPages(), ginRedoInsertListPage(), ginRedoUpdateMetapage(), gistRedoPageSplitRecord(), hash_xlog_add_ovfl_page(), hash_xlog_init_bitmap_page(), hash_xlog_init_meta_page(), heap_xlog_insert(), heap_xlog_multi_insert(), heap_xlog_update(), seq_redo(), spgRedoAddLeaf(), spgRedoAddNode(), spgRedoMoveLeafs(), spgRedoPickSplit(), and spgRedoSplitTuple().

XLogReadBufferExtended()

Buffer XLogReadBufferExtended	(	RelFileLocator	rlocator,
		ForkNumber	forknum,
		BlockNumber	blkno,
		ReadBufferMode	mode,
		Buffer	recent_buffer
	)

Definition at line 474 of file xlogutils.c.

{
    BlockNumber lastblock;
    Buffer      buffer;
    SMgrRelation smgr;
 
    Assert(blkno != P_NEW);
 
    /* Do we have a clue where the buffer might be already? */
    if (BufferIsValid(recent_buffer) &&
        mode == RBM_NORMAL &&
        ReadRecentBuffer(rlocator, forknum, blkno, recent_buffer))
    {
        buffer = recent_buffer;
        goto recent_buffer_fast_path;
    }
 
    /* Open the relation at smgr level */
    smgr = smgropen(rlocator, InvalidBackendId);
 
    /*
     * Create the target file if it doesn't already exist.  This lets us cope
     * if the replay sequence contains writes to a relation that is later
     * deleted.  (The original coding of this routine would instead suppress
     * the writes, but that seems like it risks losing valuable data if the
     * filesystem loses an inode during a crash.  Better to write the data
     * until we are actually told to delete the file.)
     */
    smgrcreate(smgr, forknum, true);
 
    lastblock = smgrnblocks(smgr, forknum);
 
    if (blkno < lastblock)
    {
        /* page exists in file */
        buffer = ReadBufferWithoutRelcache(rlocator, forknum, blkno,
                                           mode, NULL, true);
    }
    else
    {
        /* hm, page doesn't exist in file */
        if (mode == RBM_NORMAL)
        {
            log_invalid_page(rlocator, forknum, blkno, false);
            return InvalidBuffer;
        }
        if (mode == RBM_NORMAL_NO_LOG)
            return InvalidBuffer;
        /* OK to extend the file */
        /* we do this in recovery only - no rel-extension lock needed */
        Assert(InRecovery);
        buffer = InvalidBuffer;
        do
        {
            if (buffer != InvalidBuffer)
            {
                if (mode == RBM_ZERO_AND_LOCK || mode == RBM_ZERO_AND_CLEANUP_LOCK)
                    LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
                ReleaseBuffer(buffer);
            }
            buffer = ReadBufferWithoutRelcache(rlocator, forknum,
                                               P_NEW, mode, NULL, true);
        }
        while (BufferGetBlockNumber(buffer) < blkno);
        /* Handle the corner case that P_NEW returns non-consecutive pages */
        if (BufferGetBlockNumber(buffer) != blkno)
        {
            if (mode == RBM_ZERO_AND_LOCK || mode == RBM_ZERO_AND_CLEANUP_LOCK)
                LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
            ReleaseBuffer(buffer);
            buffer = ReadBufferWithoutRelcache(rlocator, forknum, blkno,
                                               mode, NULL, true);
        }
    }
 
recent_buffer_fast_path:
    if (mode == RBM_NORMAL)
    {
        /* check that page has been initialized */
        Page        page = (Page) BufferGetPage(buffer);
 
        /*
         * We assume that PageIsNew is safe without a lock. During recovery,
         * there should be no other backends that could modify the buffer at
         * the same time.
         */
        if (PageIsNew(page))
        {
            ReleaseBuffer(buffer);
            log_invalid_page(rlocator, forknum, blkno, true);
            return InvalidBuffer;
        }
    }
 
    return buffer;
}

References Assert(), BUFFER_LOCK_UNLOCK, BufferGetBlockNumber(), BufferGetPage(), BufferIsValid(), InRecovery, InvalidBackendId, InvalidBuffer, LockBuffer(), log_invalid_page(), mode, P_NEW, PageIsNew(), RBM_NORMAL, RBM_NORMAL_NO_LOG, RBM_ZERO_AND_CLEANUP_LOCK, RBM_ZERO_AND_LOCK, ReadBufferWithoutRelcache(), ReadRecentBuffer(), ReleaseBuffer(), smgrcreate(), smgrnblocks(), and smgropen().

Referenced by verifyBackupPageConsistency(), XLogReadBufferForRedoExtended(), and XLogRecordPageWithFreeSpace().

XLogReadBufferForRedo()

XLogRedoAction XLogReadBufferForRedo	(	XLogReaderState *	record,
		uint8	block_id,
		Buffer *	buf
	)

Definition at line 317 of file xlogutils.c.

{
    return XLogReadBufferForRedoExtended(record, block_id, RBM_NORMAL,
                                         false, buf);
}

References buf, RBM_NORMAL, and XLogReadBufferForRedoExtended().

Referenced by _bt_clear_incomplete_split(), brin_xlog_desummarize_page(), brin_xlog_insert_update(), brin_xlog_revmap_extend(), brin_xlog_samepage_update(), brin_xlog_update(), btree_xlog_dedup(), btree_xlog_delete(), btree_xlog_insert(), btree_xlog_mark_page_halfdead(), btree_xlog_split(), btree_xlog_unlink_page(), generic_redo(), ginRedoClearIncompleteSplit(), ginRedoDeletePage(), ginRedoInsert(), ginRedoSplit(), ginRedoUpdateMetapage(), ginRedoVacuumDataLeafPage(), ginRedoVacuumPage(), gistRedoClearFollowRight(), gistRedoDeleteRecord(), gistRedoPageDelete(), gistRedoPageUpdateRecord(), hash_xlog_add_ovfl_page(), hash_xlog_delete(), hash_xlog_init_bitmap_page(), hash_xlog_insert(), hash_xlog_move_page_contents(), hash_xlog_split_allocate_page(), hash_xlog_split_cleanup(), hash_xlog_split_complete(), hash_xlog_split_page(), hash_xlog_squeeze_page(), hash_xlog_update_meta_page(), hash_xlog_vacuum_one_page(), heap_xlog_confirm(), heap_xlog_delete(), heap_xlog_freeze_page(), heap_xlog_inplace(), heap_xlog_insert(), heap_xlog_lock(), heap_xlog_lock_updated(), heap_xlog_multi_insert(), heap_xlog_update(), heap_xlog_visible(), spgRedoAddLeaf(), spgRedoAddNode(), spgRedoMoveLeafs(), spgRedoPickSplit(), spgRedoSplitTuple(), spgRedoVacuumLeaf(), spgRedoVacuumRedirect(), spgRedoVacuumRoot(), and xlog_redo().

XLogReadBufferForRedoExtended()

XLogRedoAction XLogReadBufferForRedoExtended	(	XLogReaderState *	record,
		uint8	block_id,
		ReadBufferMode	mode,
		bool	get_cleanup_lock,
		Buffer *	buf
	)

Definition at line 354 of file xlogutils.c.

{
    XLogRecPtr  lsn = record->EndRecPtr;
    RelFileLocator rlocator;
    ForkNumber  forknum;
    BlockNumber blkno;
    Buffer      prefetch_buffer;
    Page        page;
    bool        zeromode;
    bool        willinit;
 
    if (!XLogRecGetBlockTagExtended(record, block_id, &rlocator, &forknum, &blkno,
                                    &prefetch_buffer))
    {
        /* Caller specified a bogus block_id */
        elog(PANIC, "failed to locate backup block with ID %d in WAL record",
             block_id);
    }
 
    /*
     * Make sure that if the block is marked with WILL_INIT, the caller is
     * going to initialize it. And vice versa.
     */
    zeromode = (mode == RBM_ZERO_AND_LOCK || mode == RBM_ZERO_AND_CLEANUP_LOCK);
    willinit = (XLogRecGetBlock(record, block_id)->flags & BKPBLOCK_WILL_INIT) != 0;
    if (willinit && !zeromode)
        elog(PANIC, "block with WILL_INIT flag in WAL record must be zeroed by redo routine");
    if (!willinit && zeromode)
        elog(PANIC, "block to be initialized in redo routine must be marked with WILL_INIT flag in the WAL record");
 
    /* If it has a full-page image and it should be restored, do it. */
    if (XLogRecBlockImageApply(record, block_id))
    {
        Assert(XLogRecHasBlockImage(record, block_id));
        *buf = XLogReadBufferExtended(rlocator, forknum, blkno,
                                      get_cleanup_lock ? RBM_ZERO_AND_CLEANUP_LOCK : RBM_ZERO_AND_LOCK,
                                      prefetch_buffer);
        page = BufferGetPage(*buf);
        if (!RestoreBlockImage(record, block_id, page))
            ereport(ERROR,
                    (errcode(ERRCODE_INTERNAL_ERROR),
                     errmsg_internal("%s", record->errormsg_buf)));
 
        /*
         * The page may be uninitialized. If so, we can't set the LSN because
         * that would corrupt the page.
         */
        if (!PageIsNew(page))
        {
            PageSetLSN(page, lsn);
        }
 
        MarkBufferDirty(*buf);
 
        /*
         * At the end of crash recovery the init forks of unlogged relations
         * are copied, without going through shared buffers. So we need to
         * force the on-disk state of init forks to always be in sync with the
         * state in shared buffers.
         */
        if (forknum == INIT_FORKNUM)
            FlushOneBuffer(*buf);
 
        return BLK_RESTORED;
    }
    else
    {
        *buf = XLogReadBufferExtended(rlocator, forknum, blkno, mode, prefetch_buffer);
        if (BufferIsValid(*buf))
        {
            if (mode != RBM_ZERO_AND_LOCK && mode != RBM_ZERO_AND_CLEANUP_LOCK)
            {
                if (get_cleanup_lock)
                    LockBufferForCleanup(*buf);
                else
                    LockBuffer(*buf, BUFFER_LOCK_EXCLUSIVE);
            }
            if (lsn <= PageGetLSN(BufferGetPage(*buf)))
                return BLK_DONE;
            else
                return BLK_NEEDS_REDO;
        }
        else
            return BLK_NOTFOUND;
    }
}

References Assert(), BKPBLOCK_WILL_INIT, BLK_DONE, BLK_NEEDS_REDO, BLK_NOTFOUND, BLK_RESTORED, buf, BUFFER_LOCK_EXCLUSIVE, BufferGetPage(), BufferIsValid(), elog(), XLogReaderState::EndRecPtr, ereport, errcode(), errmsg_internal(), ERROR, XLogReaderState::errormsg_buf, FlushOneBuffer(), INIT_FORKNUM, LockBuffer(), LockBufferForCleanup(), MarkBufferDirty(), mode, PageGetLSN(), PageIsNew(), PageSetLSN(), PANIC, RBM_ZERO_AND_CLEANUP_LOCK, RBM_ZERO_AND_LOCK, RestoreBlockImage(), XLogReadBufferExtended(), XLogRecBlockImageApply, XLogRecGetBlock, XLogRecGetBlockTagExtended(), and XLogRecHasBlockImage.

Referenced by btree_xlog_vacuum(), hash_xlog_delete(), hash_xlog_move_page_contents(), hash_xlog_split_allocate_page(), hash_xlog_squeeze_page(), hash_xlog_vacuum_one_page(), heap_xlog_prune(), heap_xlog_vacuum(), heap_xlog_visible(), XLogInitBufferForRedo(), and XLogReadBufferForRedo().

XLogReadDetermineTimeline()

void XLogReadDetermineTimeline	(	XLogReaderState *	state,
		XLogRecPtr	wantPage,
		uint32	wantLength,
		TimeLineID	currTLI
	)

Definition at line 735 of file xlogutils.c.

{
    const XLogRecPtr lastReadPage = (state->seg.ws_segno *
                                     state->segcxt.ws_segsize + state->segoff);
 
    Assert(wantPage != InvalidXLogRecPtr && wantPage % XLOG_BLCKSZ == 0);
    Assert(wantLength <= XLOG_BLCKSZ);
    Assert(state->readLen == 0 || state->readLen <= XLOG_BLCKSZ);
    Assert(currTLI != 0);
 
    /*
     * If the desired page is currently read in and valid, we have nothing to
     * do.
     *
     * The caller should've ensured that it didn't previously advance readOff
     * past the valid limit of this timeline, so it doesn't matter if the
     * current TLI has since become historical.
     */
    if (lastReadPage == wantPage &&
        state->readLen != 0 &&
        lastReadPage + state->readLen >= wantPage + Min(wantLength, XLOG_BLCKSZ - 1))
        return;
 
    /*
     * If we're reading from the current timeline, it hasn't become historical
     * and the page we're reading is after the last page read, we can again
     * just carry on. (Seeking backwards requires a check to make sure the
     * older page isn't on a prior timeline).
     *
     * currTLI might've become historical since the caller obtained the value,
     * but the caller is required not to read past the flush limit it saw at
     * the time it looked up the timeline. There's nothing we can do about it
     * if StartupXLOG() renames it to .partial concurrently.
     */
    if (state->currTLI == currTLI && wantPage >= lastReadPage)
    {
        Assert(state->currTLIValidUntil == InvalidXLogRecPtr);
        return;
    }
 
    /*
     * If we're just reading pages from a previously validated historical
     * timeline and the timeline we're reading from is valid until the end of
     * the current segment we can just keep reading.
     */
    if (state->currTLIValidUntil != InvalidXLogRecPtr &&
        state->currTLI != currTLI &&
        state->currTLI != 0 &&
        ((wantPage + wantLength) / state->segcxt.ws_segsize) <
        (state->currTLIValidUntil / state->segcxt.ws_segsize))
        return;
 
    /*
     * If we reach this point we're either looking up a page for random
     * access, the current timeline just became historical, or we're reading
     * from a new segment containing a timeline switch. In all cases we need
     * to determine the newest timeline on the segment.
     *
     * If it's the current timeline we can just keep reading from here unless
     * we detect a timeline switch that makes the current timeline historical.
     * If it's a historical timeline we can read all the segment on the newest
     * timeline because it contains all the old timelines' data too. So only
     * one switch check is required.
     */
    {
        /*
         * We need to re-read the timeline history in case it's been changed
         * by a promotion or replay from a cascaded replica.
         */
        List       *timelineHistory = readTimeLineHistory(currTLI);
        XLogRecPtr  endOfSegment;
 
        endOfSegment = ((wantPage / state->segcxt.ws_segsize) + 1) *
            state->segcxt.ws_segsize - 1;
        Assert(wantPage / state->segcxt.ws_segsize ==
               endOfSegment / state->segcxt.ws_segsize);
 
        /*
         * Find the timeline of the last LSN on the segment containing
         * wantPage.
         */
        state->currTLI = tliOfPointInHistory(endOfSegment, timelineHistory);
        state->currTLIValidUntil = tliSwitchPoint(state->currTLI, timelineHistory,
                                                  &state->nextTLI);
 
        Assert(state->currTLIValidUntil == InvalidXLogRecPtr ||
               wantPage + wantLength < state->currTLIValidUntil);
 
        list_free_deep(timelineHistory);
 
        elog(DEBUG3, "switched to timeline %u valid until %X/%X",
             state->currTLI,
             LSN_FORMAT_ARGS(state->currTLIValidUntil));
    }
}

References Assert(), DEBUG3, elog(), InvalidXLogRecPtr, list_free_deep(), LSN_FORMAT_ARGS, Min, readTimeLineHistory(), tliOfPointInHistory(), and tliSwitchPoint().

Referenced by logical_read_xlog_page(), and read_local_xlog_page_guts().

XLogTruncateRelation()

void XLogTruncateRelation	(	RelFileLocator	rlocator,
		ForkNumber	forkNum,
		BlockNumber	nblocks
	)

Definition at line 688 of file xlogutils.c.

{
    forget_invalid_pages(rlocator, forkNum, nblocks);
}

References forget_invalid_pages().

Referenced by smgr_redo().

Variable Documentation

InRecovery

PGDLLIMPORT bool InRecovery

extern

Definition at line 53 of file xlogutils.c.

Referenced by _mdfd_getseg(), CheckRecoveryConflictDeadlock(), create_tablespace_directories(), ExtendCommitTs(), FinishWalRecovery(), FreeSpaceMapPrepareTruncateRel(), GetXLogReceiptTime(), InitWalRecovery(), LockAcquireExtended(), mdexists(), mdprefetch(), mdread(), mdtruncate(), MultiXactAdvanceOldest(), ProcSleep(), SetMultiXactIdLimit(), SetTransactionIdLimit(), SlruPhysicalReadPage(), smgrnblocks_cached(), StartupXLOG(), TransactionIdSetStatusBit(), UpdateMinRecoveryPoint(), visibilitymap_prepare_truncate(), visibilitymap_set(), XLogNeedsFlush(), and XLogReadBufferExtended().

standbyState

PGDLLIMPORT HotStandbyState standbyState

extern

Definition at line 56 of file xlogutils.c.

Referenced by ApplyWalRecord(), CheckRecoveryConsistency(), ExpireTreeKnownAssignedTransactionIds(), InitRecoveryTransactionEnvironment(), ProcArrayApplyRecoveryInfo(), ProcArrayApplyXidAssignment(), ProcArrayInitRecovery(), RecordKnownAssignedTransactionIds(), standby_redo(), StartupProcExit(), StartupXLOG(), xact_redo(), xact_redo_abort(), xact_redo_commit(), and xlog_redo().