/*
* XLogReadBufferForRedo
* Read a page during XLOG replay
*
* Reads a block referenced by a WAL record into shared buffer cache, and
* determines what needs to be done to redo the changes to it. If the WAL
* record includes a full-page image of the page, it is restored.
*
* 'lsn' is the LSN of the record being replayed. It is compared with the
* page's LSN to determine if the record has already been replayed.
* 'block_id' is the ID number the block was registered with, when the WAL
* record was created.
*
* Returns one of the following:
*
* BLK_NEEDS_REDO - changes from the WAL record need to be applied
* BLK_DONE - block doesn't need replaying
* BLK_RESTORED - block was restored from a full-page image included in
* the record
* BLK_NOTFOUND - block was not found (because it was truncated away by
* an operation later in the WAL stream)
*
* On return, the buffer is locked in exclusive-mode, and returned in *buf.
* Note that the buffer is locked and returned even if it doesn't need
* replaying. (Getting the buffer lock is not really necessary during
* single-process crash recovery, but some subroutines such as MarkBufferDirty
* will complain if we don't have the lock. In hot standby mode it's
* definitely necessary.)
*
* Note: when a backup block is available in XLOG, we restore it
* unconditionally, even if the page in the database appears newer. This is
* to protect ourselves against database pages that were partially or
* incorrectly written during a crash. We assume that the XLOG data must be
* good because it has passed a CRC check, while the database page might not
* be. This will force us to replay all subsequent modifications of the page
* that appear in XLOG, rather than possibly ignoring them as already
* applied, but that's not a huge drawback.
*/
XLogRedoAction
XLogReadBufferForRedo(XLogReaderState *record, uint8 block_id,
Buffer *buf)
{
return XLogReadBufferForRedoExtended(record, block_id, RBM_NORMAL,
false, buf);
}
/*
* Pin and lock a buffer referenced by a WAL record, for the purpose of
* re-initializing it.
*/
Buffer
XLogInitBufferForRedo(XLogReaderState *record, uint8 block_id)
{
Buffer buf;
XLogReadBufferForRedoExtended(record, block_id, RBM_ZERO_AND_LOCK, false,
&buf);
return buf;
}
/*
* XLogReadBufferForRedo
* Read a page during XLOG replay
*
* Reads a block referenced by a WAL record into shared buffer cache, and
* determines what needs to be done to redo the changes to it. If the WAL
* record includes a full-page image of the page, it is restored.
*
* 'lsn' is the LSN of the record being replayed. It is compared with the
* page's LSN to determine if the record has already been replayed.
* 'rnode' and 'blkno' point to the block being replayed (main fork number
* is implied, use XLogReadBufferForRedoExtended for other forks).
* 'block_index' identifies the backup block in the record for the page.
*
* Returns one of the following:
*
* BLK_NEEDS_REDO - changes from the WAL record need to be applied
* BLK_DONE - block doesn't need replaying
* BLK_RESTORED - block was restored from a full-page image included in
* the record
* BLK_NOTFOUND - block was not found (because it was truncated away by
* an operation later in the WAL stream)
*
* On return, the buffer is locked in exclusive-mode, and returned in *buf.
* Note that the buffer is locked and returned even if it doesn't need
* replaying. (Getting the buffer lock is not really necessary during
* single-process crash recovery, but some subroutines such as MarkBufferDirty
* will complain if we don't have the lock. In hot standby mode it's
* definitely necessary.)
*/
XLogRedoAction
XLogReadBufferForRedo(XLogRecPtr lsn, XLogRecord *record, int block_index,
RelFileNode rnode, BlockNumber blkno,
Buffer *buf)
{
return XLogReadBufferForRedoExtended(lsn, record, block_index,
rnode, MAIN_FORKNUM, blkno,
RBM_NORMAL, false, buf);
}
static void
btree_xlog_vacuum(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
xl_btree_vacuum *xlrec = (xl_btree_vacuum *) XLogRecGetData(record);
Buffer buffer;
Page page;
BTPageOpaque opaque;
/*
* If queries might be active then we need to ensure every leaf page is
* unpinned between the lastBlockVacuumed and the current block, if there
* are any. This prevents replay of the VACUUM from reaching the stage of
* removing heap tuples while there could still be indexscans "in flight"
* to those particular tuples (see nbtree/README).
*
* It might be worth checking if there are actually any backends running;
* if not, we could just skip this.
*
* Since VACUUM can visit leaf pages out-of-order, it might issue records
* with lastBlockVacuumed >= block; that's not an error, it just means
* nothing to do now.
*
* Note: since we touch all pages in the range, we will lock non-leaf
* pages, and also any empty (all-zero) pages that may be in the index. It
* doesn't seem worth the complexity to avoid that. But it's important
* that HotStandbyActiveInReplay() will not return true if the database
* isn't yet consistent; so we need not fear reading still-corrupt blocks
* here during crash recovery.
*/
if (HotStandbyActiveInReplay())
{
RelFileNode thisrnode;
BlockNumber thisblkno;
BlockNumber blkno;
XLogRecGetBlockTag(record, 0, &thisrnode, NULL, &thisblkno);
for (blkno = xlrec->lastBlockVacuumed + 1; blkno < thisblkno; blkno++)
{
/*
* We use RBM_NORMAL_NO_LOG mode because it's not an error
* condition to see all-zero pages. The original btvacuumpage
* scan would have skipped over all-zero pages, noting them in FSM
* but not bothering to initialize them just yet; so we mustn't
* throw an error here. (We could skip acquiring the cleanup lock
* if PageIsNew, but it's probably not worth the cycles to test.)
*
* XXX we don't actually need to read the block, we just need to
* confirm it is unpinned. If we had a special call into the
* buffer manager we could optimise this so that if the block is
* not in shared_buffers we confirm it as unpinned.
*/
buffer = XLogReadBufferExtended(thisrnode, MAIN_FORKNUM, blkno,
RBM_NORMAL_NO_LOG);
if (BufferIsValid(buffer))
{
LockBufferForCleanup(buffer);
UnlockReleaseBuffer(buffer);
}
}
}
/*
* Like in btvacuumpage(), we need to take a cleanup lock on every leaf
* page. See nbtree/README for details.
*/
if (XLogReadBufferForRedoExtended(record, 0, RBM_NORMAL, true, &buffer)
== BLK_NEEDS_REDO)
{
char *ptr;
Size len;
ptr = XLogRecGetBlockData(record, 0, &len);
page = (Page) BufferGetPage(buffer);
if (len > 0)
{
OffsetNumber *unused;
OffsetNumber *unend;
unused = (OffsetNumber *) ptr;
unend = (OffsetNumber *) ((char *) ptr + len);
if ((unend - unused) > 0)
PageIndexMultiDelete(page, unused, unend - unused);
}
/*
* Mark the page as not containing any LP_DEAD items --- see comments
* in _bt_delitems_vacuum().
*/
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
opaque->btpo_flags &= ~BTP_HAS_GARBAGE;
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
}
if (BufferIsValid(buffer))
UnlockReleaseBuffer(buffer);
}
/*
* replay delete operation of hash index
*/
static void
hash_xlog_delete(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
xl_hash_delete *xldata = (xl_hash_delete *) XLogRecGetData(record);
Buffer bucketbuf = InvalidBuffer;
Buffer deletebuf;
Page page;
XLogRedoAction action;
/*
* Ensure we have a cleanup lock on primary bucket page before we start
* with the actual replay operation. This is to ensure that neither a
* scan can start nor a scan can be already-in-progress during the replay
* of this operation. If we allow scans during this operation, then they
* can miss some records or show the same record multiple times.
*/
if (xldata->is_primary_bucket_page)
action = XLogReadBufferForRedoExtended(record, 1, RBM_NORMAL, true, &deletebuf);
else
{
/*
* we don't care for return value as the purpose of reading bucketbuf
* is to ensure a cleanup lock on primary bucket page.
*/
(void) XLogReadBufferForRedoExtended(record, 0, RBM_NORMAL, true, &bucketbuf);
action = XLogReadBufferForRedo(record, 1, &deletebuf);
}
/* replay the record for deleting entries in bucket page */
if (action == BLK_NEEDS_REDO)
{
char *ptr;
Size len;
ptr = XLogRecGetBlockData(record, 1, &len);
page = (Page) BufferGetPage(deletebuf);
if (len > 0)
{
OffsetNumber *unused;
OffsetNumber *unend;
unused = (OffsetNumber *) ptr;
unend = (OffsetNumber *) ((char *) ptr + len);
if ((unend - unused) > 0)
PageIndexMultiDelete(page, unused, unend - unused);
}
/*
* Mark the page as not containing any LP_DEAD items only if
* clear_dead_marking flag is set to true. See comments in
* hashbucketcleanup() for details.
*/
if (xldata->clear_dead_marking)
{
HashPageOpaque pageopaque;
pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES;
}
PageSetLSN(page, lsn);
MarkBufferDirty(deletebuf);
}
if (BufferIsValid(deletebuf))
UnlockReleaseBuffer(deletebuf);
if (BufferIsValid(bucketbuf))
UnlockReleaseBuffer(bucketbuf);
}
/*
* replay squeeze page operation of hash index
*/
static void
hash_xlog_squeeze_page(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
xl_hash_squeeze_page *xldata = (xl_hash_squeeze_page *) XLogRecGetData(record);
Buffer bucketbuf = InvalidBuffer;
Buffer writebuf;
Buffer ovflbuf;
Buffer prevbuf = InvalidBuffer;
Buffer mapbuf;
XLogRedoAction action;
/*
* Ensure we have a cleanup lock on primary bucket page before we start
* with the actual replay operation. This is to ensure that neither a
* scan can start nor a scan can be already-in-progress during the replay
* of this operation. If we allow scans during this operation, then they
* can miss some records or show the same record multiple times.
*/
if (xldata->is_prim_bucket_same_wrt)
action = XLogReadBufferForRedoExtended(record, 1, RBM_NORMAL, true, &writebuf);
else
{
/*
* we don't care for return value as the purpose of reading bucketbuf
* is to ensure a cleanup lock on primary bucket page.
*/
(void) XLogReadBufferForRedoExtended(record, 0, RBM_NORMAL, true, &bucketbuf);
action = XLogReadBufferForRedo(record, 1, &writebuf);
}
/* replay the record for adding entries in overflow buffer */
if (action == BLK_NEEDS_REDO)
{
Page writepage;
char *begin;
char *data;
Size datalen;
uint16 ninserted = 0;
data = begin = XLogRecGetBlockData(record, 1, &datalen);
writepage = (Page) BufferGetPage(writebuf);
if (xldata->ntups > 0)
{
OffsetNumber *towrite = (OffsetNumber *) data;
data += sizeof(OffsetNumber) * xldata->ntups;
while (data - begin < datalen)
{
IndexTuple itup = (IndexTuple) data;
Size itemsz;
OffsetNumber l;
itemsz = IndexTupleDSize(*itup);
itemsz = MAXALIGN(itemsz);
data += itemsz;
l = PageAddItem(writepage, (Item) itup, itemsz, towrite[ninserted], false, false);
if (l == InvalidOffsetNumber)
elog(ERROR, "hash_xlog_squeeze_page: failed to add item to hash index page, size %d bytes",
(int) itemsz);
ninserted++;
}
}
/*
* number of tuples inserted must be same as requested in REDO record.
*/
Assert(ninserted == xldata->ntups);
/*
* if the page on which are adding tuples is a page previous to freed
* overflow page, then update its nextblno.
*/
if (xldata->is_prev_bucket_same_wrt)
{
HashPageOpaque writeopaque = (HashPageOpaque) PageGetSpecialPointer(writepage);
writeopaque->hasho_nextblkno = xldata->nextblkno;
}
PageSetLSN(writepage, lsn);
MarkBufferDirty(writebuf);
}
/* replay the record for initializing overflow buffer */
if (XLogReadBufferForRedo(record, 2, &ovflbuf) == BLK_NEEDS_REDO)
{
Page ovflpage;
ovflpage = BufferGetPage(ovflbuf);
_hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf));
PageSetLSN(ovflpage, lsn);
MarkBufferDirty(ovflbuf);
}
if (BufferIsValid(ovflbuf))
UnlockReleaseBuffer(ovflbuf);
/* replay the record for page previous to the freed overflow page */
if (!xldata->is_prev_bucket_same_wrt &&
XLogReadBufferForRedo(record, 3, &prevbuf) == BLK_NEEDS_REDO)
{
Page prevpage = BufferGetPage(prevbuf);
HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage);
prevopaque->hasho_nextblkno = xldata->nextblkno;
PageSetLSN(prevpage, lsn);
MarkBufferDirty(prevbuf);
}
if (BufferIsValid(prevbuf))
UnlockReleaseBuffer(prevbuf);
/* replay the record for page next to the freed overflow page */
if (XLogRecHasBlockRef(record, 4))
{
Buffer nextbuf;
if (XLogReadBufferForRedo(record, 4, &nextbuf) == BLK_NEEDS_REDO)
{
Page nextpage = BufferGetPage(nextbuf);
HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage);
nextopaque->hasho_prevblkno = xldata->prevblkno;
PageSetLSN(nextpage, lsn);
MarkBufferDirty(nextbuf);
}
if (BufferIsValid(nextbuf))
UnlockReleaseBuffer(nextbuf);
}
if (BufferIsValid(writebuf))
UnlockReleaseBuffer(writebuf);
if (BufferIsValid(bucketbuf))
UnlockReleaseBuffer(bucketbuf);
/*
* Note: in normal operation, we'd update the bitmap and meta page while
* still holding lock on the primary bucket page and overflow pages. But
* during replay it's not necessary to hold those locks, since no other
* index updates can be happening concurrently.
*/
/* replay the record for bitmap page */
if (XLogReadBufferForRedo(record, 5, &mapbuf) == BLK_NEEDS_REDO)
{
Page mappage = (Page) BufferGetPage(mapbuf);
uint32 *freep = NULL;
char *data;
uint32 *bitmap_page_bit;
Size datalen;
freep = HashPageGetBitmap(mappage);
data = XLogRecGetBlockData(record, 5, &datalen);
bitmap_page_bit = (uint32 *) data;
CLRBIT(freep, *bitmap_page_bit);
PageSetLSN(mappage, lsn);
MarkBufferDirty(mapbuf);
}
if (BufferIsValid(mapbuf))
UnlockReleaseBuffer(mapbuf);
/* replay the record for meta page */
if (XLogRecHasBlockRef(record, 6))
{
Buffer metabuf;
if (XLogReadBufferForRedo(record, 6, &metabuf) == BLK_NEEDS_REDO)
{
HashMetaPage metap;
Page page;
char *data;
uint32 *firstfree_ovflpage;
Size datalen;
data = XLogRecGetBlockData(record, 6, &datalen);
firstfree_ovflpage = (uint32 *) data;
page = BufferGetPage(metabuf);
metap = HashPageGetMeta(page);
metap->hashm_firstfree = *firstfree_ovflpage;
PageSetLSN(page, lsn);
MarkBufferDirty(metabuf);
}
if (BufferIsValid(metabuf))
UnlockReleaseBuffer(metabuf);
}
}
/*
* replay move of page contents for squeeze operation of hash index
*/
static void
hash_xlog_move_page_contents(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
xl_hash_move_page_contents *xldata = (xl_hash_move_page_contents *) XLogRecGetData(record);
Buffer bucketbuf = InvalidBuffer;
Buffer writebuf = InvalidBuffer;
Buffer deletebuf = InvalidBuffer;
XLogRedoAction action;
/*
* Ensure we have a cleanup lock on primary bucket page before we start
* with the actual replay operation. This is to ensure that neither a
* scan can start nor a scan can be already-in-progress during the replay
* of this operation. If we allow scans during this operation, then they
* can miss some records or show the same record multiple times.
*/
if (xldata->is_prim_bucket_same_wrt)
action = XLogReadBufferForRedoExtended(record, 1, RBM_NORMAL, true, &writebuf);
else
{
/*
* we don't care for return value as the purpose of reading bucketbuf
* is to ensure a cleanup lock on primary bucket page.
*/
(void) XLogReadBufferForRedoExtended(record, 0, RBM_NORMAL, true, &bucketbuf);
action = XLogReadBufferForRedo(record, 1, &writebuf);
}
/* replay the record for adding entries in overflow buffer */
if (action == BLK_NEEDS_REDO)
{
Page writepage;
char *begin;
char *data;
Size datalen;
uint16 ninserted = 0;
data = begin = XLogRecGetBlockData(record, 1, &datalen);
writepage = (Page) BufferGetPage(writebuf);
if (xldata->ntups > 0)
{
OffsetNumber *towrite = (OffsetNumber *) data;
data += sizeof(OffsetNumber) * xldata->ntups;
while (data - begin < datalen)
{
IndexTuple itup = (IndexTuple) data;
Size itemsz;
OffsetNumber l;
itemsz = IndexTupleDSize(*itup);
itemsz = MAXALIGN(itemsz);
data += itemsz;
l = PageAddItem(writepage, (Item) itup, itemsz, towrite[ninserted], false, false);
if (l == InvalidOffsetNumber)
elog(ERROR, "hash_xlog_move_page_contents: failed to add item to hash index page, size %d bytes",
(int) itemsz);
ninserted++;
}
}
/*
* number of tuples inserted must be same as requested in REDO record.
*/
Assert(ninserted == xldata->ntups);
PageSetLSN(writepage, lsn);
MarkBufferDirty(writebuf);
}
/* replay the record for deleting entries from overflow buffer */
if (XLogReadBufferForRedo(record, 2, &deletebuf) == BLK_NEEDS_REDO)
{
Page page;
char *ptr;
Size len;
ptr = XLogRecGetBlockData(record, 2, &len);
page = (Page) BufferGetPage(deletebuf);
if (len > 0)
{
OffsetNumber *unused;
OffsetNumber *unend;
unused = (OffsetNumber *) ptr;
unend = (OffsetNumber *) ((char *) ptr + len);
if ((unend - unused) > 0)
PageIndexMultiDelete(page, unused, unend - unused);
}
PageSetLSN(page, lsn);
MarkBufferDirty(deletebuf);
}
/*
* Replay is complete, now we can release the buffers. We release locks at
* end of replay operation to ensure that we hold lock on primary bucket
* page till end of operation. We can optimize by releasing the lock on
* write buffer as soon as the operation for same is complete, if it is
* not same as primary bucket page, but that doesn't seem to be worth
* complicating the code.
*/
if (BufferIsValid(deletebuf))
UnlockReleaseBuffer(deletebuf);
if (BufferIsValid(writebuf))
UnlockReleaseBuffer(writebuf);
if (BufferIsValid(bucketbuf))
UnlockReleaseBuffer(bucketbuf);
}
/*
* replay allocation of page for split operation
*/
static void
hash_xlog_split_allocate_page(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
xl_hash_split_allocate_page *xlrec = (xl_hash_split_allocate_page *) XLogRecGetData(record);
Buffer oldbuf;
Buffer newbuf;
Buffer metabuf;
Size datalen PG_USED_FOR_ASSERTS_ONLY;
char *data;
XLogRedoAction action;
/*
* To be consistent with normal operation, here we take cleanup locks on
* both the old and new buckets even though there can't be any concurrent
* inserts.
*/
/* replay the record for old bucket */
action = XLogReadBufferForRedoExtended(record, 0, RBM_NORMAL, true, &oldbuf);
/*
* Note that we still update the page even if it was restored from a full
* page image, because the special space is not included in the image.
*/
if (action == BLK_NEEDS_REDO || action == BLK_RESTORED)
{
Page oldpage;
HashPageOpaque oldopaque;
oldpage = BufferGetPage(oldbuf);
oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage);
oldopaque->hasho_flag = xlrec->old_bucket_flag;
oldopaque->hasho_prevblkno = xlrec->new_bucket;
PageSetLSN(oldpage, lsn);
MarkBufferDirty(oldbuf);
}
/* replay the record for new bucket */
newbuf = XLogInitBufferForRedo(record, 1);
_hash_initbuf(newbuf, xlrec->new_bucket, xlrec->new_bucket,
xlrec->new_bucket_flag, true);
if (!IsBufferCleanupOK(newbuf))
elog(PANIC, "hash_xlog_split_allocate_page: failed to acquire cleanup lock");
MarkBufferDirty(newbuf);
PageSetLSN(BufferGetPage(newbuf), lsn);
/*
* We can release the lock on old bucket early as well but doing here to
* consistent with normal operation.
*/
if (BufferIsValid(oldbuf))
UnlockReleaseBuffer(oldbuf);
if (BufferIsValid(newbuf))
UnlockReleaseBuffer(newbuf);
/*
* Note: in normal operation, we'd update the meta page while still
* holding lock on the old and new bucket pages. But during replay it's
* not necessary to hold those locks, since no other bucket splits can be
* happening concurrently.
*/
/* replay the record for metapage changes */
if (XLogReadBufferForRedo(record, 2, &metabuf) == BLK_NEEDS_REDO)
{
Page page;
HashMetaPage metap;
page = BufferGetPage(metabuf);
metap = HashPageGetMeta(page);
metap->hashm_maxbucket = xlrec->new_bucket;
data = XLogRecGetBlockData(record, 2, &datalen);
if (xlrec->flags & XLH_SPLIT_META_UPDATE_MASKS)
{
uint32 lowmask;
uint32 *highmask;
/* extract low and high masks. */
memcpy(&lowmask, data, sizeof(uint32));
highmask = (uint32 *) ((char *) data + sizeof(uint32));
/* update metapage */
metap->hashm_lowmask = lowmask;
metap->hashm_highmask = *highmask;
data += sizeof(uint32) * 2;
}
if (xlrec->flags & XLH_SPLIT_META_UPDATE_SPLITPOINT)
{
uint32 ovflpoint;
uint32 *ovflpages;
/* extract information of overflow pages. */
memcpy(&ovflpoint, data, sizeof(uint32));
ovflpages = (uint32 *) ((char *) data + sizeof(uint32));
/* update metapage */
metap->hashm_spares[ovflpoint] = *ovflpages;
metap->hashm_ovflpoint = ovflpoint;
}
MarkBufferDirty(metabuf);
PageSetLSN(BufferGetPage(metabuf), lsn);
}
if (BufferIsValid(metabuf))
UnlockReleaseBuffer(metabuf);
}
/*
* replay delete operation in hash index to remove
* tuples marked as DEAD during index tuple insertion.
*/
static void
hash_xlog_vacuum_one_page(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
xl_hash_vacuum_one_page *xldata;
Buffer buffer;
Buffer metabuf;
Page page;
XLogRedoAction action;
HashPageOpaque pageopaque;
xldata = (xl_hash_vacuum_one_page *) XLogRecGetData(record);
/*
* If we have any conflict processing to do, it must happen before we
* update the page.
*
* Hash index records that are marked as LP_DEAD and being removed during
* hash index tuple insertion can conflict with standby queries. You might
* think that vacuum records would conflict as well, but we've handled
* that already. XLOG_HEAP2_CLEANUP_INFO records provide the highest xid
* cleaned by the vacuum of the heap and so we can resolve any conflicts
* just once when that arrives. After that we know that no conflicts
* exist from individual hash index vacuum records on that index.
*/
if (InHotStandby)
{
TransactionId latestRemovedXid =
hash_xlog_vacuum_get_latestRemovedXid(record);
RelFileNode rnode;
XLogRecGetBlockTag(record, 0, &rnode, NULL, NULL);
ResolveRecoveryConflictWithSnapshot(latestRemovedXid, rnode);
}
action = XLogReadBufferForRedoExtended(record, 0, RBM_NORMAL, true, &buffer);
if (action == BLK_NEEDS_REDO)
{
char *ptr;
Size len;
ptr = XLogRecGetBlockData(record, 0, &len);
page = (Page) BufferGetPage(buffer);
if (len > 0)
{
OffsetNumber *unused;
OffsetNumber *unend;
unused = (OffsetNumber *) ptr;
unend = (OffsetNumber *) ((char *) ptr + len);
if ((unend - unused) > 0)
PageIndexMultiDelete(page, unused, unend - unused);
}
/*
* Mark the page as not containing any LP_DEAD items. See comments
* in _hash_vacuum_one_page() for details.
*/
pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES;
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
}
if (BufferIsValid(buffer))
UnlockReleaseBuffer(buffer);
if (XLogReadBufferForRedo(record, 1, &metabuf) == BLK_NEEDS_REDO)
{
Page metapage;
HashMetaPage metap;
metapage = BufferGetPage(metabuf);
metap = HashPageGetMeta(metapage);
metap->hashm_ntuples -= xldata->ntuples;
PageSetLSN(metapage, lsn);
MarkBufferDirty(metabuf);
}
if (BufferIsValid(metabuf))
UnlockReleaseBuffer(metabuf);
}
