Unite ReadBufferWithFork, ReadBufferWithStrategy, and ZeroOrReadBuffer

functions into one ReadBufferExtended function, that takes the strategy
and mode as argument. There's three modes, RBM_NORMAL which is the default
used by plain ReadBuffer(), RBM_ZERO, which replaces ZeroOrReadBuffer, and
a new mode RBM_ZERO_ON_ERROR, which allows callers to read corrupt pages
without throwing an error. The FSM needs the new mode to recover from
corrupt pages, which could happend if we crash after extending an FSM file,
and the new page is "torn".

Add fork number to some error messages in bufmgr.c, that still lacked it.

1 files changed, 32 insertions, 12 deletions

diff --git a/src/backend/access/gin/ginvacuum.c b/src/backend/access/gin/ginvacuum.c
index 733710ef563..ae6459c9fac 100644
--- a/src/backend/access/gin/ginvacuum.c
+++ b/src/backend/access/gin/ginvacuum.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *			$PostgreSQL: pgsql/src/backend/access/gin/ginvacuum.c,v 1.23 2008/10/06 08:04:11 heikki Exp $
+ *			$PostgreSQL: pgsql/src/backend/access/gin/ginvacuum.c,v 1.24 2008/10/31 15:04:59 heikki Exp $
  *-------------------------------------------------------------------------
  */
 
@@ -155,10 +155,14 @@ xlogVacuumPage(Relation index, Buffer buffer)
 static bool
 ginVacuumPostingTreeLeaves(GinVacuumState *gvs, BlockNumber blkno, bool isRoot, Buffer *rootBuffer)
 {
-	Buffer		buffer = ReadBufferWithStrategy(gvs->index, blkno, gvs->strategy);
-	Page		page = BufferGetPage(buffer);
+	Buffer		buffer;
+	Page		page;
 	bool		hasVoidPage = FALSE;
 
+	buffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, blkno,
+								RBM_NORMAL, gvs->strategy);
+	page = BufferGetPage(buffer);
+
 	/*
 	 * We should be sure that we don't concurrent with inserts, insert process
 	 * never release root page until end (but it can unlock it and lock
@@ -241,13 +245,24 @@ static void
 ginDeletePage(GinVacuumState *gvs, BlockNumber deleteBlkno, BlockNumber leftBlkno,
 			  BlockNumber parentBlkno, OffsetNumber myoff, bool isParentRoot)
 {
-	Buffer		dBuffer = ReadBufferWithStrategy(gvs->index, deleteBlkno, gvs->strategy);
-	Buffer		lBuffer = (leftBlkno == InvalidBlockNumber) ?
-	InvalidBuffer : ReadBufferWithStrategy(gvs->index, leftBlkno, gvs->strategy);
-	Buffer		pBuffer = ReadBufferWithStrategy(gvs->index, parentBlkno, gvs->strategy);
+	Buffer		dBuffer;
+	Buffer		lBuffer;
+	Buffer		pBuffer;
 	Page		page,
 				parentPage;
 
+	dBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, deleteBlkno,
+								 RBM_NORMAL, gvs->strategy);
+
+	if (leftBlkno != InvalidBlockNumber)
+		lBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, leftBlkno,
+									 RBM_NORMAL, gvs->strategy);
+	else
+		lBuffer = InvalidBuffer;
+
+	pBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, parentBlkno,
+								 RBM_NORMAL, gvs->strategy);
+
 	LockBuffer(dBuffer, GIN_EXCLUSIVE);
 	if (!isParentRoot)			/* parent is already locked by
 								 * LockBufferForCleanup() */
@@ -401,7 +416,8 @@ ginScanToDelete(GinVacuumState *gvs, BlockNumber blkno, bool isRoot, DataPageDel
 			me = parent->child;
 	}
 
-	buffer = ReadBufferWithStrategy(gvs->index, blkno, gvs->strategy);
+	buffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, blkno,
+								RBM_NORMAL, gvs->strategy);
 	page = BufferGetPage(buffer);
 
 	Assert(GinPageIsData(page));
@@ -589,7 +605,8 @@ ginbulkdelete(PG_FUNCTION_ARGS)
 	gvs.strategy = info->strategy;
 	initGinState(&gvs.ginstate, index);
 
-	buffer = ReadBufferWithStrategy(index, blkno, info->strategy);
+	buffer = ReadBufferExtended(index, MAIN_FORKNUM, blkno,
+								RBM_NORMAL, info->strategy);
 
 	/* find leaf page */
 	for (;;)
@@ -621,7 +638,8 @@ ginbulkdelete(PG_FUNCTION_ARGS)
 		Assert(blkno != InvalidBlockNumber);
 
 		UnlockReleaseBuffer(buffer);
-		buffer = ReadBufferWithStrategy(index, blkno, info->strategy);
+		buffer = ReadBufferExtended(index, MAIN_FORKNUM, blkno,
+									RBM_NORMAL, info->strategy);
 	}
 
 	/* right now we found leftmost page in entry's BTree */
@@ -663,7 +681,8 @@ ginbulkdelete(PG_FUNCTION_ARGS)
 		if (blkno == InvalidBlockNumber)		/* rightmost page */
 			break;
 
-		buffer = ReadBufferWithStrategy(index, blkno, info->strategy);
+		buffer = ReadBufferExtended(index, MAIN_FORKNUM, blkno,
+									RBM_NORMAL, info->strategy);
 		LockBuffer(buffer, GIN_EXCLUSIVE);
 	}
 
@@ -718,7 +737,8 @@ ginvacuumcleanup(PG_FUNCTION_ARGS)
 
 		vacuum_delay_point();
 
-		buffer = ReadBufferWithStrategy(index, blkno, info->strategy);
+		buffer = ReadBufferExtended(index, MAIN_FORKNUM, blkno,
+									RBM_NORMAL, info->strategy);
 		LockBuffer(buffer, GIN_SHARE);
 		page = (Page) BufferGetPage(buffer);