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, 10 insertions, 5 deletions

diff --git a/src/backend/access/gist/gistvacuum.c b/src/backend/access/gist/gistvacuum.c
index 2a917b6528a..80710ae7368 100644
--- a/src/backend/access/gist/gistvacuum.c
+++ b/src/backend/access/gist/gistvacuum.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/gist/gistvacuum.c,v 1.38 2008/10/06 08:04:11 heikki Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/gist/gistvacuum.c,v 1.39 2008/10/31 15:04:59 heikki Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -86,7 +86,8 @@ gistDeleteSubtree(GistVacuum *gv, BlockNumber blkno)
 	Buffer		buffer;
 	Page		page;
 
-	buffer = ReadBufferWithStrategy(gv->index, blkno, gv->strategy);
+	buffer = ReadBufferExtended(gv->index, MAIN_FORKNUM, blkno, RBM_NORMAL,
+								gv->strategy);
 	LockBuffer(buffer, GIST_EXCLUSIVE);
 	page = (Page) BufferGetPage(buffer);
 
@@ -306,7 +307,8 @@ gistVacuumUpdate(GistVacuum *gv, BlockNumber blkno, bool needunion)
 
 	vacuum_delay_point();
 
-	buffer = ReadBufferWithStrategy(gv->index, blkno, gv->strategy);
+	buffer = ReadBufferExtended(gv->index, MAIN_FORKNUM, blkno, RBM_NORMAL,
+								gv->strategy);
 	LockBuffer(buffer, GIST_EXCLUSIVE);
 	gistcheckpage(gv->index, buffer);
 	page = (Page) BufferGetPage(buffer);
@@ -595,7 +597,8 @@ gistvacuumcleanup(PG_FUNCTION_ARGS)
 
 		vacuum_delay_point();
 
-		buffer = ReadBufferWithStrategy(rel, blkno, info->strategy);
+		buffer = ReadBufferExtended(rel, MAIN_FORKNUM, blkno, RBM_NORMAL,
+									info->strategy);
 		LockBuffer(buffer, GIST_SHARE);
 		page = (Page) BufferGetPage(buffer);
 
@@ -691,13 +694,15 @@ gistbulkdelete(PG_FUNCTION_ARGS)
 
 	while (stack)
 	{
-		Buffer		buffer = ReadBufferWithStrategy(rel, stack->blkno, info->strategy);
+		Buffer		buffer;
 		Page		page;
 		OffsetNumber i,
 					maxoff;
 		IndexTuple	idxtuple;
 		ItemId		iid;
 
+		buffer = ReadBufferExtended(rel, MAIN_FORKNUM, stack->blkno,
+									RBM_NORMAL, info->strategy);
 		LockBuffer(buffer, GIST_SHARE);
 		gistcheckpage(rel, buffer);
 		page = (Page) BufferGetPage(buffer);