Example #1
0
static void
spgRedoPickSplit(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogPickSplit *xldata = (spgxlogPickSplit *) ptr;
	SpGistInnerTuple innerTuple;
	SpGistState state;
	OffsetNumber *toDelete;
	OffsetNumber *toInsert;
	uint8	   *leafPageSelect;
	Buffer		srcBuffer;
	Buffer		destBuffer;
	Page		page;
	int			bbi;
	int			i;

	fillFakeState(&state, xldata->stateSrc);

	ptr += MAXALIGN(sizeof(spgxlogPickSplit));
	innerTuple = (SpGistInnerTuple) ptr;
	ptr += innerTuple->size;
	toDelete = (OffsetNumber *) ptr;
	ptr += MAXALIGN(sizeof(OffsetNumber) * xldata->nDelete);
	toInsert = (OffsetNumber *) ptr;
	ptr += MAXALIGN(sizeof(OffsetNumber) * xldata->nInsert);
	leafPageSelect = (uint8 *) ptr;
	ptr += MAXALIGN(sizeof(uint8) * xldata->nInsert);

	/* now ptr points to the list of leaf tuples */

	/*
	 * It's a bit tricky to identify which pages have been handled as
	 * full-page images, so we explicitly count each referenced buffer.
	 */
	bbi = 0;

	if (xldata->blknoSrc == SPGIST_HEAD_BLKNO)
	{
		/* when splitting root, we touch it only in the guise of new inner */
		srcBuffer = InvalidBuffer;
	}
	else if (xldata->initSrc)
	{
		/* just re-init the source page */
		srcBuffer = XLogReadBuffer(xldata->node, xldata->blknoSrc, true);
		Assert(BufferIsValid(srcBuffer));
		page = (Page) BufferGetPage(srcBuffer);

		SpGistInitBuffer(srcBuffer, SPGIST_LEAF);
		/* don't update LSN etc till we're done with it */
	}
	else
	{
		/* delete the specified tuples from source page */
		if (!(record->xl_info & XLR_SET_BKP_BLOCK(bbi)))
		{
			srcBuffer = XLogReadBuffer(xldata->node, xldata->blknoSrc, false);
			if (BufferIsValid(srcBuffer))
			{
				page = BufferGetPage(srcBuffer);
				if (!XLByteLE(lsn, PageGetLSN(page)))
				{
					/*
					 * We have it a bit easier here than in doPickSplit(),
					 * because we know the inner tuple's location already,
					 * so we can inject the correct redirection tuple now.
					 */
					if (!state.isBuild)
						spgPageIndexMultiDelete(&state, page,
												toDelete, xldata->nDelete,
												SPGIST_REDIRECT,
												SPGIST_PLACEHOLDER,
												xldata->blknoInner,
												xldata->offnumInner);
					else
						spgPageIndexMultiDelete(&state, page,
												toDelete, xldata->nDelete,
												SPGIST_PLACEHOLDER,
												SPGIST_PLACEHOLDER,
												InvalidBlockNumber,
												InvalidOffsetNumber);

					/* don't update LSN etc till we're done with it */
				}
			}
		}
		else
			srcBuffer = InvalidBuffer;
		bbi++;
	}

	/* try to access dest page if any */
	if (xldata->blknoDest == InvalidBlockNumber)
	{
		destBuffer = InvalidBuffer;
	}
	else if (xldata->initDest)
	{
		/* just re-init the dest page */
		destBuffer = XLogReadBuffer(xldata->node, xldata->blknoDest, true);
		Assert(BufferIsValid(destBuffer));
		page = (Page) BufferGetPage(destBuffer);

		SpGistInitBuffer(destBuffer, SPGIST_LEAF);
		/* don't update LSN etc till we're done with it */
	}
	else
	{
		if (!(record->xl_info & XLR_SET_BKP_BLOCK(bbi)))
			destBuffer = XLogReadBuffer(xldata->node, xldata->blknoDest, false);
		else
			destBuffer = InvalidBuffer;
		bbi++;
	}

	/* restore leaf tuples to src and/or dest page */
	for (i = 0; i < xldata->nInsert; i++)
	{
		SpGistLeafTuple lt = (SpGistLeafTuple) ptr;
		Buffer		leafBuffer;

		ptr += lt->size;

		leafBuffer = leafPageSelect[i] ? destBuffer : srcBuffer;
		if (!BufferIsValid(leafBuffer))
			continue;			/* no need to touch this page */
		page = BufferGetPage(leafBuffer);

		if (!XLByteLE(lsn, PageGetLSN(page)))
		{
			addOrReplaceTuple(page, (Item) lt, lt->size, toInsert[i]);
		}
	}

	/* Now update src and dest page LSNs */
	if (BufferIsValid(srcBuffer))
	{
		page = BufferGetPage(srcBuffer);
		if (!XLByteLE(lsn, PageGetLSN(page)))
		{
			PageSetLSN(page, lsn);
			PageSetTLI(page, ThisTimeLineID);
			MarkBufferDirty(srcBuffer);
		}
		UnlockReleaseBuffer(srcBuffer);
	}
	if (BufferIsValid(destBuffer))
	{
		page = BufferGetPage(destBuffer);
		if (!XLByteLE(lsn, PageGetLSN(page)))
		{
			PageSetLSN(page, lsn);
			PageSetTLI(page, ThisTimeLineID);
			MarkBufferDirty(destBuffer);
		}
		UnlockReleaseBuffer(destBuffer);
	}

	/* restore new inner tuple */
	if (!(record->xl_info & XLR_SET_BKP_BLOCK(bbi)))
	{
		Buffer		buffer = XLogReadBuffer(xldata->node, xldata->blknoInner,
											xldata->initInner);

		if (BufferIsValid(buffer))
		{
			page = BufferGetPage(buffer);

			if (xldata->initInner)
				SpGistInitBuffer(buffer, 0);

			if (!XLByteLE(lsn, PageGetLSN(page)))
			{
				addOrReplaceTuple(page, (Item) innerTuple, innerTuple->size,
								  xldata->offnumInner);

				/* if inner is also parent, update link while we're here */
				if (xldata->blknoInner == xldata->blknoParent)
				{
					SpGistInnerTuple parent;

					parent = (SpGistInnerTuple) PageGetItem(page,
									PageGetItemId(page, xldata->offnumParent));
					spgUpdateNodeLink(parent, xldata->nodeI,
									  xldata->blknoInner, xldata->offnumInner);
				}

				PageSetLSN(page, lsn);
				PageSetTLI(page, ThisTimeLineID);
				MarkBufferDirty(buffer);
			}
			UnlockReleaseBuffer(buffer);
		}
	}
	bbi++;

	/* update parent downlink, unless we did it above */
	if (xldata->blknoParent == InvalidBlockNumber)
	{
		/* no parent cause we split the root */
		Assert(xldata->blknoInner == SPGIST_HEAD_BLKNO);
	}
	else if (xldata->blknoInner != xldata->blknoParent)
	{
		if (!(record->xl_info & XLR_SET_BKP_BLOCK(bbi)))
		{
			Buffer		buffer = XLogReadBuffer(xldata->node, xldata->blknoParent, false);

			if (BufferIsValid(buffer))
			{
				page = BufferGetPage(buffer);

				if (!XLByteLE(lsn, PageGetLSN(page)))
				{
					SpGistInnerTuple parent;

					parent = (SpGistInnerTuple) PageGetItem(page,
									PageGetItemId(page, xldata->offnumParent));
					spgUpdateNodeLink(parent, xldata->nodeI,
									  xldata->blknoInner, xldata->offnumInner);

					PageSetLSN(page, lsn);
					PageSetTLI(page, ThisTimeLineID);
					MarkBufferDirty(buffer);
				}
				UnlockReleaseBuffer(buffer);
			}
		}
	}
}
Example #2
0
static void
spgRedoAddLeaf(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogAddLeaf *xldata = (spgxlogAddLeaf *) ptr;
	SpGistLeafTuple leafTuple;
	Buffer		buffer;
	Page		page;

	/* we assume this is adequately aligned */
	ptr += sizeof(spgxlogAddLeaf);
	leafTuple = (SpGistLeafTuple) ptr;

	if (!(record->xl_info & XLR_BKP_BLOCK_1))
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoLeaf,
								xldata->newPage);
		if (BufferIsValid(buffer))
		{
			page = BufferGetPage(buffer);

			if (xldata->newPage)
				SpGistInitBuffer(buffer, SPGIST_LEAF);

			if (!XLByteLE(lsn, PageGetLSN(page)))
			{
				/* insert new tuple */
				if (xldata->offnumLeaf != xldata->offnumHeadLeaf)
				{
					/* normal cases, tuple was added by SpGistPageAddNewItem */
					addOrReplaceTuple(page, (Item) leafTuple, leafTuple->size,
									  xldata->offnumLeaf);

					/* update head tuple's chain link if needed */
					if (xldata->offnumHeadLeaf != InvalidOffsetNumber)
					{
						SpGistLeafTuple head;

						head = (SpGistLeafTuple) PageGetItem(page,
														 PageGetItemId(page, xldata->offnumHeadLeaf));
						Assert(head->nextOffset == leafTuple->nextOffset);
						head->nextOffset = xldata->offnumLeaf;
					}
				}
				else
				{
					/* replacing a DEAD tuple */
					PageIndexTupleDelete(page, xldata->offnumLeaf);
					if (PageAddItem(page,
									(Item) leafTuple, leafTuple->size,
									xldata->offnumLeaf, false, false) != xldata->offnumLeaf)
						elog(ERROR, "failed to add item of size %u to SPGiST index page",
							 leafTuple->size);
				}

				PageSetLSN(page, lsn);
				PageSetTLI(page, ThisTimeLineID);
				MarkBufferDirty(buffer);
			}
			UnlockReleaseBuffer(buffer);
		}
	}

	/* update parent downlink if necessary */
	if (xldata->blknoParent != InvalidBlockNumber &&
		!(record->xl_info & XLR_BKP_BLOCK_2))
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoParent, false);
		if (BufferIsValid(buffer))
		{
			page = BufferGetPage(buffer);
			if (!XLByteLE(lsn, PageGetLSN(page)))
			{
				SpGistInnerTuple tuple;

				tuple = (SpGistInnerTuple) PageGetItem(page,
													   PageGetItemId(page, xldata->offnumParent));

				spgUpdateNodeLink(tuple, xldata->nodeI,
								  xldata->blknoLeaf, xldata->offnumLeaf);

				PageSetLSN(page, lsn);
				PageSetTLI(page, ThisTimeLineID);
				MarkBufferDirty(buffer);
			}
			UnlockReleaseBuffer(buffer);
		}
	}
}
Example #3
0
static void
spgRedoAddNode(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogAddNode *xldata = (spgxlogAddNode *) ptr;
	SpGistInnerTuple innerTuple;
	SpGistState state;
	Buffer		buffer;
	Page		page;
	int			bbi;

	/* we assume this is adequately aligned */
	ptr += sizeof(spgxlogAddNode);
	innerTuple = (SpGistInnerTuple) ptr;

	fillFakeState(&state, xldata->stateSrc);

	if (xldata->blknoNew == InvalidBlockNumber)
	{
		/* update in place */
		Assert(xldata->blknoParent == InvalidBlockNumber);
		if (!(record->xl_info & XLR_BKP_BLOCK_1))
		{
			buffer = XLogReadBuffer(xldata->node, xldata->blkno, false);
			if (BufferIsValid(buffer))
			{
				page = BufferGetPage(buffer);
				if (!XLByteLE(lsn, PageGetLSN(page)))
				{
					PageIndexTupleDelete(page, xldata->offnum);
					if (PageAddItem(page, (Item) innerTuple, innerTuple->size,
									xldata->offnum,
									false, false) != xldata->offnum)
						elog(ERROR, "failed to add item of size %u to SPGiST index page",
							 innerTuple->size);

					PageSetLSN(page, lsn);
					PageSetTLI(page, ThisTimeLineID);
					MarkBufferDirty(buffer);
				}
				UnlockReleaseBuffer(buffer);
			}
		}
	}
	else
	{
		/* Install new tuple first so redirect is valid */
		if (!(record->xl_info & XLR_BKP_BLOCK_2))
		{
			buffer = XLogReadBuffer(xldata->node, xldata->blknoNew,
									xldata->newPage);
			if (BufferIsValid(buffer))
			{
				page = BufferGetPage(buffer);

				if (xldata->newPage)
					SpGistInitBuffer(buffer, 0);

				if (!XLByteLE(lsn, PageGetLSN(page)))
				{
					addOrReplaceTuple(page, (Item) innerTuple,
									  innerTuple->size, xldata->offnumNew);

					PageSetLSN(page, lsn);
					PageSetTLI(page, ThisTimeLineID);
					MarkBufferDirty(buffer);
				}
				UnlockReleaseBuffer(buffer);
			}
		}

		/* Delete old tuple, replacing it with redirect or placeholder tuple */
		if (!(record->xl_info & XLR_BKP_BLOCK_1))
		{
			buffer = XLogReadBuffer(xldata->node, xldata->blkno, false);
			if (BufferIsValid(buffer))
			{
				page = BufferGetPage(buffer);
				if (!XLByteLE(lsn, PageGetLSN(page)))
				{
					SpGistDeadTuple dt;

					if (state.isBuild)
						dt = spgFormDeadTuple(&state, SPGIST_PLACEHOLDER,
											  InvalidBlockNumber,
											  InvalidOffsetNumber);
					else
						dt = spgFormDeadTuple(&state, SPGIST_REDIRECT,
											  xldata->blknoNew,
											  xldata->offnumNew);

					PageIndexTupleDelete(page, xldata->offnum);
					if (PageAddItem(page, (Item) dt, dt->size,
									xldata->offnum,
									false, false) != xldata->offnum)
						elog(ERROR, "failed to add item of size %u to SPGiST index page",
							 dt->size);

					if (state.isBuild)
						SpGistPageGetOpaque(page)->nPlaceholder++;
					else
						SpGistPageGetOpaque(page)->nRedirection++;

					PageSetLSN(page, lsn);
					PageSetTLI(page, ThisTimeLineID);
					MarkBufferDirty(buffer);
				}
				UnlockReleaseBuffer(buffer);
			}
		}

		/*
		 * Update parent downlink.  Since parent could be in either of the
		 * previous two buffers, it's a bit tricky to determine which BKP bit
		 * applies.
		 */
		if (xldata->blknoParent == xldata->blkno)
			bbi = 0;
		else if (xldata->blknoParent == xldata->blknoNew)
			bbi = 1;
		else
			bbi = 2;

		if (!(record->xl_info & XLR_SET_BKP_BLOCK(bbi)))
		{
			buffer = XLogReadBuffer(xldata->node, xldata->blknoParent, false);
			if (BufferIsValid(buffer))
			{
				page = BufferGetPage(buffer);
				if (!XLByteLE(lsn, PageGetLSN(page)))
				{
					SpGistInnerTuple innerTuple;

					innerTuple = (SpGistInnerTuple) PageGetItem(page,
																PageGetItemId(page, xldata->offnumParent));

					spgUpdateNodeLink(innerTuple, xldata->nodeI,
									  xldata->blknoNew, xldata->offnumNew);

					PageSetLSN(page, lsn);
					PageSetTLI(page, ThisTimeLineID);
					MarkBufferDirty(buffer);
				}
				UnlockReleaseBuffer(buffer);
			}
		}
	}
}
Example #4
0
static void
spgRedoSplitTuple(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogSplitTuple *xldata = (spgxlogSplitTuple *) ptr;
	SpGistInnerTuple prefixTuple;
	SpGistInnerTuple postfixTuple;
	Buffer		buffer;
	Page		page;

	/* we assume this is adequately aligned */
	ptr += sizeof(spgxlogSplitTuple);
	prefixTuple = (SpGistInnerTuple) ptr;
	ptr += prefixTuple->size;
	postfixTuple = (SpGistInnerTuple) ptr;

	/* insert postfix tuple first to avoid dangling link */
	if (xldata->blknoPostfix != xldata->blknoPrefix &&
		!(record->xl_info & XLR_BKP_BLOCK_2))
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoPostfix,
								xldata->newPage);
		if (BufferIsValid(buffer))
		{
			page = BufferGetPage(buffer);

			if (xldata->newPage)
				SpGistInitBuffer(buffer, 0);

			if (!XLByteLE(lsn, PageGetLSN(page)))
			{
				addOrReplaceTuple(page, (Item) postfixTuple,
								  postfixTuple->size, xldata->offnumPostfix);

				PageSetLSN(page, lsn);
				PageSetTLI(page, ThisTimeLineID);
				MarkBufferDirty(buffer);
			}
			UnlockReleaseBuffer(buffer);
		}
	}

	/* now handle the original page */
	if (!(record->xl_info & XLR_BKP_BLOCK_1))
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoPrefix, false);
		if (BufferIsValid(buffer))
		{
			page = BufferGetPage(buffer);
			if (!XLByteLE(lsn, PageGetLSN(page)))
			{
				PageIndexTupleDelete(page, xldata->offnumPrefix);
				if (PageAddItem(page, (Item) prefixTuple, prefixTuple->size,
								xldata->offnumPrefix, false, false) != xldata->offnumPrefix)
					elog(ERROR, "failed to add item of size %u to SPGiST index page",
						 prefixTuple->size);

				if (xldata->blknoPostfix == xldata->blknoPrefix)
					addOrReplaceTuple(page, (Item) postfixTuple,
									  postfixTuple->size,
									  xldata->offnumPostfix);

				PageSetLSN(page, lsn);
				PageSetTLI(page, ThisTimeLineID);
				MarkBufferDirty(buffer);
			}
			UnlockReleaseBuffer(buffer);
		}
	}
}
Example #5
0
static void
spgRedoPickSplit(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogPickSplit *xldata = (spgxlogPickSplit *) ptr;
	char	   *innerTuple;
	SpGistInnerTupleData innerTupleHdr;
	SpGistState state;
	OffsetNumber *toDelete;
	OffsetNumber *toInsert;
	uint8	   *leafPageSelect;
	Buffer		srcBuffer;
	Buffer		destBuffer;
	Page		srcPage;
	Page		destPage;
	Buffer		innerBuffer;
	Page		page;
	int			bbi;
	int			i;
	XLogRedoAction action;

	fillFakeState(&state, xldata->stateSrc);

	ptr += SizeOfSpgxlogPickSplit;
	toDelete = (OffsetNumber *) ptr;
	ptr += sizeof(OffsetNumber) * xldata->nDelete;
	toInsert = (OffsetNumber *) ptr;
	ptr += sizeof(OffsetNumber) * xldata->nInsert;
	leafPageSelect = (uint8 *) ptr;
	ptr += sizeof(uint8) * xldata->nInsert;

	innerTuple = ptr;
	/* the inner tuple is unaligned, so make a copy to access its header */
	memcpy(&innerTupleHdr, innerTuple, sizeof(SpGistInnerTupleData));
	ptr += innerTupleHdr.size;

	/* now ptr points to the list of leaf tuples */

	/*
	 * It's a bit tricky to identify which pages have been handled as
	 * full-page images, so we explicitly count each referenced buffer.
	 */
	bbi = 0;

	if (SpGistBlockIsRoot(xldata->blknoSrc))
	{
		/* when splitting root, we touch it only in the guise of new inner */
		srcBuffer = InvalidBuffer;
		srcPage = NULL;
	}
	else if (xldata->initSrc)
	{
		/* just re-init the source page */
		srcBuffer = XLogReadBuffer(xldata->node, xldata->blknoSrc, true);
		Assert(BufferIsValid(srcBuffer));
		srcPage = (Page) BufferGetPage(srcBuffer);

		SpGistInitBuffer(srcBuffer,
					 SPGIST_LEAF | (xldata->storesNulls ? SPGIST_NULLS : 0));
		/* don't update LSN etc till we're done with it */
	}
	else
	{
		/*
		 * Delete the specified tuples from source page.  (In case we're in
		 * Hot Standby, we need to hold lock on the page till we're done
		 * inserting leaf tuples and the new inner tuple, else the added
		 * redirect tuple will be a dangling link.)
		 */
		if (XLogReadBufferForRedo(lsn, record, bbi,
								  xldata->node, xldata->blknoSrc,
								  &srcBuffer) == BLK_NEEDS_REDO)
		{
			srcPage = BufferGetPage(srcBuffer);

			/*
			 * We have it a bit easier here than in doPickSplit(), because we
			 * know the inner tuple's location already, so we can inject the
			 * correct redirection tuple now.
			 */
			if (!state.isBuild)
				spgPageIndexMultiDelete(&state, srcPage,
										toDelete, xldata->nDelete,
										SPGIST_REDIRECT,
										SPGIST_PLACEHOLDER,
										xldata->blknoInner,
										xldata->offnumInner);
			else
				spgPageIndexMultiDelete(&state, srcPage,
										toDelete, xldata->nDelete,
										SPGIST_PLACEHOLDER,
										SPGIST_PLACEHOLDER,
										InvalidBlockNumber,
										InvalidOffsetNumber);

			/* don't update LSN etc till we're done with it */
		}
		else
		{
			srcPage = NULL;		/* don't do any page updates */
		}
		bbi++;
	}

	/* try to access dest page if any */
	if (xldata->blknoDest == InvalidBlockNumber)
	{
		destBuffer = InvalidBuffer;
		destPage = NULL;
	}
	else if (xldata->initDest)
	{
		/* just re-init the dest page */
		destBuffer = XLogReadBuffer(xldata->node, xldata->blknoDest, true);
		Assert(BufferIsValid(destBuffer));
		destPage = (Page) BufferGetPage(destBuffer);

		SpGistInitBuffer(destBuffer,
					 SPGIST_LEAF | (xldata->storesNulls ? SPGIST_NULLS : 0));
		/* don't update LSN etc till we're done with it */
	}
	else
	{
		/*
		 * We could probably release the page lock immediately in the
		 * full-page-image case, but for safety let's hold it till later.
		 */
		if (XLogReadBufferForRedo(lsn, record, bbi,
								  xldata->node, xldata->blknoDest,
								  &destBuffer) == BLK_NEEDS_REDO)
		{
			destPage = (Page) BufferGetPage(destBuffer);
		}
		else
		{
			destPage = NULL;	/* don't do any page updates */
		}
		bbi++;
	}

	/* restore leaf tuples to src and/or dest page */
	for (i = 0; i < xldata->nInsert; i++)
	{
		char	   *leafTuple;
		SpGistLeafTupleData leafTupleHdr;

		/* the tuples are not aligned, so must copy to access the size field. */
		leafTuple = ptr;
		memcpy(&leafTupleHdr, leafTuple, sizeof(SpGistLeafTupleData));
		ptr += leafTupleHdr.size;

		page = leafPageSelect[i] ? destPage : srcPage;
		if (page == NULL)
			continue;			/* no need to touch this page */

		addOrReplaceTuple(page, (Item) leafTuple, leafTupleHdr.size,
						  toInsert[i]);
	}

	/* Now update src and dest page LSNs if needed */
	if (srcPage != NULL)
	{
		PageSetLSN(srcPage, lsn);
		MarkBufferDirty(srcBuffer);
	}
	if (destPage != NULL)
	{
		PageSetLSN(destPage, lsn);
		MarkBufferDirty(destBuffer);
	}

	/* restore new inner tuple */
	if (xldata->initInner)
	{
		innerBuffer = XLogReadBuffer(xldata->node, xldata->blknoInner, true);
		SpGistInitBuffer(innerBuffer,
						 (xldata->storesNulls ? SPGIST_NULLS : 0));
		action = BLK_NEEDS_REDO;
	}
	else
		action = XLogReadBufferForRedo(lsn, record, bbi, xldata->node,
									   xldata->blknoInner, &innerBuffer);

	if (action == BLK_NEEDS_REDO)
	{
		page = BufferGetPage(innerBuffer);

		addOrReplaceTuple(page, (Item) innerTuple, innerTupleHdr.size,
						  xldata->offnumInner);

		/* if inner is also parent, update link while we're here */
		if (xldata->blknoInner == xldata->blknoParent)
		{
			SpGistInnerTuple parent;

			parent = (SpGistInnerTuple) PageGetItem(page,
								  PageGetItemId(page, xldata->offnumParent));
			spgUpdateNodeLink(parent, xldata->nodeI,
							  xldata->blknoInner, xldata->offnumInner);
		}

		PageSetLSN(page, lsn);
		MarkBufferDirty(innerBuffer);
	}
	if (BufferIsValid(innerBuffer))
		UnlockReleaseBuffer(innerBuffer);
	bbi++;

	/*
	 * Now we can release the leaf-page locks.  It's okay to do this before
	 * updating the parent downlink.
	 */
	if (BufferIsValid(srcBuffer))
		UnlockReleaseBuffer(srcBuffer);
	if (BufferIsValid(destBuffer))
		UnlockReleaseBuffer(destBuffer);

	/* update parent downlink, unless we did it above */
	if (xldata->blknoParent == InvalidBlockNumber)
	{
		/* no parent cause we split the root */
		Assert(SpGistBlockIsRoot(xldata->blknoInner));
	}
	else if (xldata->blknoInner != xldata->blknoParent)
	{
		Buffer		parentBuffer;

		if (XLogReadBufferForRedo(lsn, record, bbi,
								  xldata->node, xldata->blknoParent,
								  &parentBuffer) == BLK_NEEDS_REDO)
		{
			SpGistInnerTuple parent;

			page = BufferGetPage(parentBuffer);

			parent = (SpGistInnerTuple) PageGetItem(page,
								  PageGetItemId(page, xldata->offnumParent));
			spgUpdateNodeLink(parent, xldata->nodeI,
							  xldata->blknoInner, xldata->offnumInner);

			PageSetLSN(page, lsn);
			MarkBufferDirty(parentBuffer);
		}
		if (BufferIsValid(parentBuffer))
			UnlockReleaseBuffer(parentBuffer);
	}
}
Example #6
0
static void
spgRedoMoveLeafs(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogMoveLeafs *xldata = (spgxlogMoveLeafs *) ptr;
	SpGistState state;
	OffsetNumber *toDelete;
	OffsetNumber *toInsert;
	int			nInsert;
	Buffer		buffer;
	Page		page;

	fillFakeState(&state, xldata->stateSrc);

	nInsert = xldata->replaceDead ? 1 : xldata->nMoves + 1;

	ptr += MAXALIGN(sizeof(spgxlogMoveLeafs));
	toDelete = (OffsetNumber *) ptr;
	ptr += MAXALIGN(sizeof(OffsetNumber) * xldata->nMoves);
	toInsert = (OffsetNumber *) ptr;
	ptr += MAXALIGN(sizeof(OffsetNumber) * nInsert);

	/* now ptr points to the list of leaf tuples */

	/* Insert tuples on the dest page (do first, so redirect is valid) */
	if (!(record->xl_info & XLR_BKP_BLOCK_2))
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoDst,
								xldata->newPage);
		if (BufferIsValid(buffer))
		{
			page = BufferGetPage(buffer);

			if (xldata->newPage)
				SpGistInitBuffer(buffer, SPGIST_LEAF);

			if (!XLByteLE(lsn, PageGetLSN(page)))
			{
				int			i;

				for (i = 0; i < nInsert; i++)
				{
					SpGistLeafTuple lt = (SpGistLeafTuple) ptr;

					addOrReplaceTuple(page, (Item) lt, lt->size, toInsert[i]);
					ptr += lt->size;
				}

				PageSetLSN(page, lsn);
				PageSetTLI(page, ThisTimeLineID);
				MarkBufferDirty(buffer);
			}
			UnlockReleaseBuffer(buffer);
		}
	}

	/* Delete tuples from the source page, inserting a redirection pointer */
	if (!(record->xl_info & XLR_BKP_BLOCK_1))
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoSrc, false);
		if (BufferIsValid(buffer))
		{
			page = BufferGetPage(buffer);
			if (!XLByteLE(lsn, PageGetLSN(page)))
			{
				spgPageIndexMultiDelete(&state, page, toDelete, xldata->nMoves,
										state.isBuild ? SPGIST_PLACEHOLDER : SPGIST_REDIRECT,
										SPGIST_PLACEHOLDER,
										xldata->blknoDst,
										toInsert[nInsert - 1]);

				PageSetLSN(page, lsn);
				PageSetTLI(page, ThisTimeLineID);
				MarkBufferDirty(buffer);
			}
			UnlockReleaseBuffer(buffer);
		}
	}

	/* And update the parent downlink */
	if (!(record->xl_info & XLR_BKP_BLOCK_3))
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoParent, false);
		if (BufferIsValid(buffer))
		{
			page = BufferGetPage(buffer);
			if (!XLByteLE(lsn, PageGetLSN(page)))
			{
				SpGistInnerTuple tuple;

				tuple = (SpGistInnerTuple) PageGetItem(page,
													   PageGetItemId(page, xldata->offnumParent));

				spgUpdateNodeLink(tuple, xldata->nodeI,
								  xldata->blknoDst, toInsert[nInsert - 1]);

				PageSetLSN(page, lsn);
				PageSetTLI(page, ThisTimeLineID);
				MarkBufferDirty(buffer);
			}
			UnlockReleaseBuffer(buffer);
		}
	}
}
Example #7
0
static void
spgRedoSplitTuple(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogSplitTuple *xldata = (spgxlogSplitTuple *) ptr;
	char	   *prefixTuple;
	SpGistInnerTupleData prefixTupleHdr;
	char	   *postfixTuple;
	SpGistInnerTupleData postfixTupleHdr;
	Buffer		buffer;
	Page		page;

	ptr += sizeof(spgxlogSplitTuple);
	prefixTuple = ptr;
	/* the prefix tuple is unaligned, so make a copy to access its header */
	memcpy(&prefixTupleHdr, prefixTuple, sizeof(SpGistInnerTupleData));
	ptr += prefixTupleHdr.size;
	postfixTuple = ptr;
	/* postfix tuple is also unaligned */
	memcpy(&postfixTupleHdr, postfixTuple, sizeof(SpGistInnerTupleData));

	/*
	 * In normal operation we would have both pages locked simultaneously; but
	 * in WAL replay it should be safe to update them one at a time, as long
	 * as we do it in the right order.
	 */

	/* insert postfix tuple first to avoid dangling link */
	if (xldata->blknoPostfix != xldata->blknoPrefix)
	{
		XLogRedoAction action;

		if (xldata->newPage)
		{
			buffer = XLogReadBuffer(xldata->node, xldata->blknoPostfix, true);
			/* SplitTuple is not used for nulls pages */
			SpGistInitBuffer(buffer, 0);
			action = BLK_NEEDS_REDO;
		}
		else
			action = XLogReadBufferForRedo(lsn, record, 1,
										   xldata->node, xldata->blknoPostfix,
										   &buffer);

		if (action == BLK_NEEDS_REDO)
		{
			page = BufferGetPage(buffer);

			addOrReplaceTuple(page, (Item) postfixTuple,
							  postfixTupleHdr.size, xldata->offnumPostfix);

			PageSetLSN(page, lsn);
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);
	}

	/* now handle the original page */
	if (XLogReadBufferForRedo(lsn, record, 0, xldata->node, xldata->blknoPrefix,
							  &buffer) == BLK_NEEDS_REDO)
	{
		page = BufferGetPage(buffer);
		PageIndexTupleDelete(page, xldata->offnumPrefix);
		if (PageAddItem(page, (Item) prefixTuple, prefixTupleHdr.size,
				 xldata->offnumPrefix, false, false) != xldata->offnumPrefix)
			elog(ERROR, "failed to add item of size %u to SPGiST index page",
				 prefixTupleHdr.size);

		if (xldata->blknoPostfix == xldata->blknoPrefix)
			addOrReplaceTuple(page, (Item) postfixTuple, postfixTupleHdr.size,
							  xldata->offnumPostfix);

		PageSetLSN(page, lsn);
		MarkBufferDirty(buffer);
	}
	if (BufferIsValid(buffer))
		UnlockReleaseBuffer(buffer);
}
Example #8
0
static void
spgRedoAddNode(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogAddNode *xldata = (spgxlogAddNode *) ptr;
	char	   *innerTuple;
	SpGistInnerTupleData innerTupleHdr;
	SpGistState state;
	Buffer		buffer;
	Page		page;
	int			bbi;
	XLogRedoAction action;

	ptr += sizeof(spgxlogAddNode);
	innerTuple = ptr;
	/* the tuple is unaligned, so make a copy to access its header */
	memcpy(&innerTupleHdr, innerTuple, sizeof(SpGistInnerTupleData));

	fillFakeState(&state, xldata->stateSrc);

	if (xldata->blknoNew == InvalidBlockNumber)
	{
		/* update in place */
		Assert(xldata->blknoParent == InvalidBlockNumber);
		if (XLogReadBufferForRedo(lsn, record, 0, xldata->node, xldata->blkno,
								  &buffer) == BLK_NEEDS_REDO)
		{
			page = BufferGetPage(buffer);
			PageIndexTupleDelete(page, xldata->offnum);
			if (PageAddItem(page, (Item) innerTuple, innerTupleHdr.size,
							xldata->offnum, false, false) != xldata->offnum)
				elog(ERROR, "failed to add item of size %u to SPGiST index page",
					 innerTupleHdr.size);

			PageSetLSN(page, lsn);
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);
	}
	else
	{
		/*
		 * In normal operation we would have all three pages (source, dest,
		 * and parent) locked simultaneously; but in WAL replay it should be
		 * safe to update them one at a time, as long as we do it in the right
		 * order.
		 *
		 * The logic here depends on the assumption that blkno != blknoNew,
		 * else we can't tell which BKP bit goes with which page, and the LSN
		 * checks could go wrong too.
		 */
		Assert(xldata->blkno != xldata->blknoNew);

		/* Install new tuple first so redirect is valid */
		if (xldata->newPage)
		{
			buffer = XLogReadBuffer(xldata->node, xldata->blknoNew, true);
			/* AddNode is not used for nulls pages */
			SpGistInitBuffer(buffer, 0);
			action = BLK_NEEDS_REDO;
		}
		else
			action = XLogReadBufferForRedo(lsn, record, 1,
										   xldata->node, xldata->blknoNew,
										   &buffer);
		if (action == BLK_NEEDS_REDO)
		{
			page = BufferGetPage(buffer);

			addOrReplaceTuple(page, (Item) innerTuple,
							  innerTupleHdr.size, xldata->offnumNew);

			/*
			 * If parent is in this same page, don't advance LSN; doing so
			 * would fool us into not applying the parent downlink update
			 * below.  We'll update the LSN when we fix the parent downlink.
			 */
			if (xldata->blknoParent != xldata->blknoNew)
			{
				PageSetLSN(page, lsn);
			}
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);

		/* Delete old tuple, replacing it with redirect or placeholder tuple */
		if (XLogReadBufferForRedo(lsn, record, 0, xldata->node, xldata->blkno,
								  &buffer) == BLK_NEEDS_REDO)
		{
			SpGistDeadTuple dt;

			page = BufferGetPage(buffer);

			if (state.isBuild)
				dt = spgFormDeadTuple(&state, SPGIST_PLACEHOLDER,
									  InvalidBlockNumber,
									  InvalidOffsetNumber);
			else
				dt = spgFormDeadTuple(&state, SPGIST_REDIRECT,
									  xldata->blknoNew,
									  xldata->offnumNew);

			PageIndexTupleDelete(page, xldata->offnum);
			if (PageAddItem(page, (Item) dt, dt->size, xldata->offnum,
							false, false) != xldata->offnum)
				elog(ERROR, "failed to add item of size %u to SPGiST index page",
					 dt->size);

			if (state.isBuild)
				SpGistPageGetOpaque(page)->nPlaceholder++;
			else
				SpGistPageGetOpaque(page)->nRedirection++;

			/*
			 * If parent is in this same page, don't advance LSN; doing so
			 * would fool us into not applying the parent downlink update
			 * below.  We'll update the LSN when we fix the parent downlink.
			 */
			if (xldata->blknoParent != xldata->blkno)
			{
				PageSetLSN(page, lsn);
			}
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);

		/*
		 * Update parent downlink.  Since parent could be in either of the
		 * previous two buffers, it's a bit tricky to determine which BKP bit
		 * applies.
		 */
		if (xldata->blknoParent == xldata->blkno)
			bbi = 0;
		else if (xldata->blknoParent == xldata->blknoNew)
			bbi = 1;
		else
			bbi = 2;

		if (record->xl_info & XLR_BKP_BLOCK(bbi))
		{
			if (bbi == 2)		/* else we already did it */
				(void) RestoreBackupBlock(lsn, record, bbi, false, false);
			action = BLK_RESTORED;
			buffer = InvalidBuffer;
		}
		else
		{
			action = XLogReadBufferForRedo(lsn, record, bbi, xldata->node,
										   xldata->blknoParent, &buffer);
			Assert(action != BLK_RESTORED);
		}
		if (action == BLK_NEEDS_REDO)
		{
			SpGistInnerTuple innerTuple;

			page = BufferGetPage(buffer);

			innerTuple = (SpGistInnerTuple) PageGetItem(page,
								  PageGetItemId(page, xldata->offnumParent));

			spgUpdateNodeLink(innerTuple, xldata->nodeI,
							  xldata->blknoNew, xldata->offnumNew);

			PageSetLSN(page, lsn);
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);
	}
}
Example #9
0
static void
spgRedoMoveLeafs(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogMoveLeafs *xldata = (spgxlogMoveLeafs *) ptr;
	SpGistState state;
	OffsetNumber *toDelete;
	OffsetNumber *toInsert;
	int			nInsert;
	Buffer		buffer;
	Page		page;
	XLogRedoAction action;

	fillFakeState(&state, xldata->stateSrc);

	nInsert = xldata->replaceDead ? 1 : xldata->nMoves + 1;

	ptr += SizeOfSpgxlogMoveLeafs;
	toDelete = (OffsetNumber *) ptr;
	ptr += sizeof(OffsetNumber) * xldata->nMoves;
	toInsert = (OffsetNumber *) ptr;
	ptr += sizeof(OffsetNumber) * nInsert;

	/* now ptr points to the list of leaf tuples */

	/*
	 * In normal operation we would have all three pages (source, dest, and
	 * parent) locked simultaneously; but in WAL replay it should be safe to
	 * update them one at a time, as long as we do it in the right order.
	 */

	/* Insert tuples on the dest page (do first, so redirect is valid) */
	if (xldata->newPage)
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoDst, true);
		SpGistInitBuffer(buffer,
					 SPGIST_LEAF | (xldata->storesNulls ? SPGIST_NULLS : 0));
		action = BLK_NEEDS_REDO;
	}
	else
		action = XLogReadBufferForRedo(lsn, record, 1,
									   xldata->node, xldata->blknoDst,
									   &buffer);
	if (action == BLK_NEEDS_REDO)
	{
		int			i;

		page = BufferGetPage(buffer);

		for (i = 0; i < nInsert; i++)
		{
			char	   *leafTuple;
			SpGistLeafTupleData leafTupleHdr;

			/*
			 * the tuples are not aligned, so must copy to access the size
			 * field.
			 */
			leafTuple = ptr;
			memcpy(&leafTupleHdr, leafTuple, sizeof(SpGistLeafTupleData));

			addOrReplaceTuple(page, (Item) leafTuple,
							  leafTupleHdr.size, toInsert[i]);
			ptr += leafTupleHdr.size;
		}

		PageSetLSN(page, lsn);
		MarkBufferDirty(buffer);
	}
	if (BufferIsValid(buffer))
		UnlockReleaseBuffer(buffer);

	/* Delete tuples from the source page, inserting a redirection pointer */
	if (XLogReadBufferForRedo(lsn, record, 0, xldata->node, xldata->blknoSrc,
							  &buffer) == BLK_NEEDS_REDO)
	{
		page = BufferGetPage(buffer);
		spgPageIndexMultiDelete(&state, page, toDelete, xldata->nMoves,
						state.isBuild ? SPGIST_PLACEHOLDER : SPGIST_REDIRECT,
								SPGIST_PLACEHOLDER,
								xldata->blknoDst,
								toInsert[nInsert - 1]);

		PageSetLSN(page, lsn);
		MarkBufferDirty(buffer);
	}
	if (BufferIsValid(buffer))
		UnlockReleaseBuffer(buffer);

	/* And update the parent downlink */
	if (XLogReadBufferForRedo(lsn, record, 2, xldata->node, xldata->blknoParent,
							  &buffer) == BLK_NEEDS_REDO)
	{
		SpGistInnerTuple tuple;

		page = BufferGetPage(buffer);

		tuple = (SpGistInnerTuple) PageGetItem(page,
								  PageGetItemId(page, xldata->offnumParent));

		spgUpdateNodeLink(tuple, xldata->nodeI,
						  xldata->blknoDst, toInsert[nInsert - 1]);

		PageSetLSN(page, lsn);
		MarkBufferDirty(buffer);
	}
	if (BufferIsValid(buffer))
		UnlockReleaseBuffer(buffer);
}
Example #10
0
static void
spgRedoAddLeaf(XLogRecPtr lsn, XLogRecord *record)
{
	char	   *ptr = XLogRecGetData(record);
	spgxlogAddLeaf *xldata = (spgxlogAddLeaf *) ptr;
	char	   *leafTuple;
	SpGistLeafTupleData leafTupleHdr;
	Buffer		buffer;
	Page		page;
	XLogRedoAction action;

	ptr += sizeof(spgxlogAddLeaf);
	leafTuple = ptr;
	/* the leaf tuple is unaligned, so make a copy to access its header */
	memcpy(&leafTupleHdr, leafTuple, sizeof(SpGistLeafTupleData));

	/*
	 * In normal operation we would have both current and parent pages locked
	 * simultaneously; but in WAL replay it should be safe to update the leaf
	 * page before updating the parent.
	 */
	if (xldata->newPage)
	{
		buffer = XLogReadBuffer(xldata->node, xldata->blknoLeaf, true);
		SpGistInitBuffer(buffer,
					 SPGIST_LEAF | (xldata->storesNulls ? SPGIST_NULLS : 0));
		action = BLK_NEEDS_REDO;
	}
	else
		action = XLogReadBufferForRedo(lsn, record, 0,
									   xldata->node, xldata->blknoLeaf,
									   &buffer);

	if (action == BLK_NEEDS_REDO)
	{
		page = BufferGetPage(buffer);

		/* insert new tuple */
		if (xldata->offnumLeaf != xldata->offnumHeadLeaf)
		{
			/* normal cases, tuple was added by SpGistPageAddNewItem */
			addOrReplaceTuple(page, (Item) leafTuple, leafTupleHdr.size,
							  xldata->offnumLeaf);

			/* update head tuple's chain link if needed */
			if (xldata->offnumHeadLeaf != InvalidOffsetNumber)
			{
				SpGistLeafTuple head;

				head = (SpGistLeafTuple) PageGetItem(page,
								PageGetItemId(page, xldata->offnumHeadLeaf));
				Assert(head->nextOffset == leafTupleHdr.nextOffset);
				head->nextOffset = xldata->offnumLeaf;
			}
		}
		else
		{
			/* replacing a DEAD tuple */
			PageIndexTupleDelete(page, xldata->offnumLeaf);
			if (PageAddItem(page, (Item) leafTuple, leafTupleHdr.size,
					 xldata->offnumLeaf, false, false) != xldata->offnumLeaf)
				elog(ERROR, "failed to add item of size %u to SPGiST index page",
					 leafTupleHdr.size);
		}

		PageSetLSN(page, lsn);
		MarkBufferDirty(buffer);
	}
	if (BufferIsValid(buffer))
		UnlockReleaseBuffer(buffer);

	/* update parent downlink if necessary */
	if (xldata->blknoParent != InvalidBlockNumber)
	{
		if (XLogReadBufferForRedo(lsn, record, 1,
								  xldata->node, xldata->blknoParent,
								  &buffer) == BLK_NEEDS_REDO)
		{
			SpGistInnerTuple tuple;

			page = BufferGetPage(buffer);

			tuple = (SpGistInnerTuple) PageGetItem(page,
								  PageGetItemId(page, xldata->offnumParent));

			spgUpdateNodeLink(tuple, xldata->nodeI,
							  xldata->blknoLeaf, xldata->offnumLeaf);

			PageSetLSN(page, lsn);
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);
	}
}
Example #11
0
static void
spgRedoAddNode(XLogReaderState *record)
{
	XLogRecPtr	lsn = record->EndRecPtr;
	char	   *ptr = XLogRecGetData(record);
	spgxlogAddNode *xldata = (spgxlogAddNode *) ptr;
	char	   *innerTuple;
	SpGistInnerTupleData innerTupleHdr;
	SpGistState state;
	Buffer		buffer;
	Page		page;
	XLogRedoAction action;

	ptr += sizeof(spgxlogAddNode);
	innerTuple = ptr;
	/* the tuple is unaligned, so make a copy to access its header */
	memcpy(&innerTupleHdr, innerTuple, sizeof(SpGistInnerTupleData));

	fillFakeState(&state, xldata->stateSrc);

	if (!XLogRecHasBlockRef(record, 1))
	{
		/* update in place */
		Assert(xldata->parentBlk == -1);
		if (XLogReadBufferForRedo(record, 0, &buffer) == BLK_NEEDS_REDO)
		{
			page = BufferGetPage(buffer);

			PageIndexTupleDelete(page, xldata->offnum);
			if (PageAddItem(page, (Item) innerTuple, innerTupleHdr.size,
							xldata->offnum,
							false, false) != xldata->offnum)
				elog(ERROR, "failed to add item of size %u to SPGiST index page",
					 innerTupleHdr.size);

			PageSetLSN(page, lsn);
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);
	}
	else
	{
		BlockNumber blkno;
		BlockNumber blknoNew;

		XLogRecGetBlockTag(record, 0, NULL, NULL, &blkno);
		XLogRecGetBlockTag(record, 1, NULL, NULL, &blknoNew);

		/*
		 * In normal operation we would have all three pages (source, dest,
		 * and parent) locked simultaneously; but in WAL replay it should be
		 * safe to update them one at a time, as long as we do it in the right
		 * order. We must insert the new tuple before replacing the old tuple
		 * with the redirect tuple.
		 */

		/* Install new tuple first so redirect is valid */
		if (xldata->newPage)
		{
			/* AddNode is not used for nulls pages */
			buffer = XLogInitBufferForRedo(record, 1);
			SpGistInitBuffer(buffer, 0);
			action = BLK_NEEDS_REDO;
		}
		else
			action = XLogReadBufferForRedo(record, 1, &buffer);
		if (action == BLK_NEEDS_REDO)
		{
			page = BufferGetPage(buffer);

			addOrReplaceTuple(page, (Item) innerTuple,
							  innerTupleHdr.size, xldata->offnumNew);

			/*
			 * If parent is in this same page, update it now.
			 */
			if (xldata->parentBlk == 1)
			{
				SpGistInnerTuple parentTuple;

				parentTuple = (SpGistInnerTuple) PageGetItem(page,
															 PageGetItemId(page, xldata->offnumParent));

				spgUpdateNodeLink(parentTuple, xldata->nodeI,
								  blknoNew, xldata->offnumNew);
			}
			PageSetLSN(page, lsn);
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);

		/* Delete old tuple, replacing it with redirect or placeholder tuple */
		if (XLogReadBufferForRedo(record, 0, &buffer) == BLK_NEEDS_REDO)
		{
			SpGistDeadTuple dt;

			page = BufferGetPage(buffer);

			if (state.isBuild)
				dt = spgFormDeadTuple(&state, SPGIST_PLACEHOLDER,
									  InvalidBlockNumber,
									  InvalidOffsetNumber);
			else
				dt = spgFormDeadTuple(&state, SPGIST_REDIRECT,
									  blknoNew,
									  xldata->offnumNew);

			PageIndexTupleDelete(page, xldata->offnum);
			if (PageAddItem(page, (Item) dt, dt->size,
							xldata->offnum,
							false, false) != xldata->offnum)
				elog(ERROR, "failed to add item of size %u to SPGiST index page",
					 dt->size);

			if (state.isBuild)
				SpGistPageGetOpaque(page)->nPlaceholder++;
			else
				SpGistPageGetOpaque(page)->nRedirection++;

			/*
			 * If parent is in this same page, update it now.
			 */
			if (xldata->parentBlk == 0)
			{
				SpGistInnerTuple parentTuple;

				parentTuple = (SpGistInnerTuple) PageGetItem(page,
															 PageGetItemId(page, xldata->offnumParent));

				spgUpdateNodeLink(parentTuple, xldata->nodeI,
								  blknoNew, xldata->offnumNew);
			}
			PageSetLSN(page, lsn);
			MarkBufferDirty(buffer);
		}
		if (BufferIsValid(buffer))
			UnlockReleaseBuffer(buffer);

		/*
		 * Update parent downlink (if we didn't do it as part of the source or
		 * destination page update already).
		 */
		if (xldata->parentBlk == 2)
		{
			if (XLogReadBufferForRedo(record, 2, &buffer) == BLK_NEEDS_REDO)
			{
				SpGistInnerTuple parentTuple;

				page = BufferGetPage(buffer);

				parentTuple = (SpGistInnerTuple) PageGetItem(page,
															 PageGetItemId(page, xldata->offnumParent));

				spgUpdateNodeLink(parentTuple, xldata->nodeI,
								  blknoNew, xldata->offnumNew);

				PageSetLSN(page, lsn);
				MarkBufferDirty(buffer);
			}
			if (BufferIsValid(buffer))
				UnlockReleaseBuffer(buffer);
		}
	}
}