* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/gist/gist.c,v 1.127 2005/10/18 01:06:22 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/access/gist/gist.c,v 1.128 2005/11/06 22:39:20 tgl Exp $
*
*-------------------------------------------------------------------------
*/
* ready to recheck path in a bad case... We remember, that page->lsn
* should never be invalid.
*/
- while (true)
+ for (;;)
{
-
if (XLogRecPtrIsInvalid(state->stack->lsn))
state->stack->buffer = ReadBuffer(state->r, state->stack->blkno);
LockBuffer(state->stack->buffer, GIST_SHARE);
+ gistcheckpage(state->r, state->stack->buffer);
state->stack->page = (Page) BufferGetPage(state->stack->buffer);
opaque = GistPageGetOpaque(state->stack->page);
continue;
}
-
if (!GistPageIsLeaf(state->stack->page))
{
/*
}
/*
- * Traverse the tree to find path from root page,
- * to prevent deadlocks, it should lock only one page simultaneously.
- * Function uses in recovery and usial mode, so should work with different
- * read functions (gistReadAndLockBuffer and XLogReadBuffer)
+ * Traverse the tree to find path from root page.
+ *
* returns from the begining of closest parent;
+ *
+ * Function is used in both regular and recovery mode, so must work with
+ * different read functions (gistReadAndLockBuffer and XLogReadBuffer)
+ *
+ * To prevent deadlocks, this should lock only one page simultaneously.
*/
GISTInsertStack *
-gistFindPath(Relation r, BlockNumber child, Buffer (*myReadBuffer) (Relation, BlockNumber))
+gistFindPath(Relation r, BlockNumber child,
+ Buffer (*myReadBuffer) (Relation, BlockNumber))
{
Page page;
Buffer buffer;
while (top && top->blkno != child)
{
- buffer = myReadBuffer(r, top->blkno); /* buffer locked */
+ buffer = myReadBuffer(r, top->blkno); /* locks buffer */
+ gistcheckpage(r, buffer);
page = (Page) BufferGetPage(buffer);
if (GistPageIsLeaf(page))
GISTInsertStack *parent = child->parent;
LockBuffer(parent->buffer, GIST_EXCLUSIVE);
+ gistcheckpage(r, parent->buffer);
parent->page = (Page) BufferGetPage(parent->buffer);
-
/* here we don't need to distinguish between split and page update */
if (parent->childoffnum == InvalidOffsetNumber || !XLByteEQ(parent->lsn, PageGetLSN(parent->page)))
{
break;
parent->buffer = ReadBuffer(r, parent->blkno);
LockBuffer(parent->buffer, GIST_EXCLUSIVE);
+ gistcheckpage(r, parent->buffer);
parent->page = (Page) BufferGetPage(parent->buffer);
}
ptr = parent = gistFindPath(r, child->blkno, gistReadAndLockBuffer);
Assert(ptr != NULL);
- /* read all buffers as supposed in caller */
+ /* read all buffers as expected by caller */
+ /* note we don't lock them or gistcheckpage them here! */
while (ptr)
{
ptr->buffer = ReadBuffer(r, ptr->blkno);
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/gist/gistget.c,v 1.52 2005/10/06 02:29:07 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/access/gist/gistget.c,v 1.53 2005/11/06 22:39:20 tgl Exp $
*
*-------------------------------------------------------------------------
*/
maxoff;
LockBuffer(buffer, GIST_SHARE);
+ gistcheckpage(r, buffer);
p = (Page) BufferGetPage(buffer);
if (buffer == so->curbuf && XLByteEQ(so->stack->lsn, PageGetLSN(p)))
/* First of all, we need lock buffer */
Assert(so->curbuf != InvalidBuffer);
LockBuffer(so->curbuf, GIST_SHARE);
+ gistcheckpage(scan->indexRelation, so->curbuf);
p = BufferGetPage(so->curbuf);
opaque = GistPageGetOpaque(p);
resetoffset = false;
continue;
}
- if (!GistPageIsLeaf(p) || resetoffset || ItemPointerIsValid(&scan->currentItemData) == false)
+ if (!GistPageIsLeaf(p) || resetoffset ||
+ !ItemPointerIsValid(&scan->currentItemData))
{
if (ScanDirectionIsBackward(dir))
n = PageGetMaxOffsetNumber(p);
return ntids;
}
- so->curbuf = ReleaseAndReadBuffer(so->curbuf, scan->indexRelation,
+ so->curbuf = ReleaseAndReadBuffer(so->curbuf,
+ scan->indexRelation,
stk->block);
/* XXX go up */
break;
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/gist/gistutil.c,v 1.7 2005/09/22 20:44:36 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/gist/gistutil.c,v 1.8 2005/11/06 22:39:20 tgl Exp $
*-------------------------------------------------------------------------
*/
#include "postgres.h"
PointerGetDatum(penalty));
}
-void
-GISTInitBuffer(Buffer b, uint32 f)
-{
- GISTPageOpaque opaque;
- Page page;
- Size pageSize;
-
- pageSize = BufferGetPageSize(b);
- page = BufferGetPage(b);
- PageInit(page, pageSize, sizeof(GISTPageOpaqueData));
-
- opaque = GistPageGetOpaque(page);
- opaque->flags = f;
- opaque->rightlink = InvalidBlockNumber;
- memset(&(opaque->nsn), 0, sizeof(GistNSN));
-}
-
void
gistUserPicksplit(Relation r, GistEntryVector *entryvec, GIST_SPLITVEC *v,
IndexTuple *itup, int len, GISTSTATE *giststate)
}
}
+/*
+ * Initialize a new index page
+ */
+void
+GISTInitBuffer(Buffer b, uint32 f)
+{
+ GISTPageOpaque opaque;
+ Page page;
+ Size pageSize;
+
+ pageSize = BufferGetPageSize(b);
+ page = BufferGetPage(b);
+ PageInit(page, pageSize, sizeof(GISTPageOpaqueData));
+
+ opaque = GistPageGetOpaque(page);
+ opaque->flags = f;
+ opaque->rightlink = InvalidBlockNumber;
+ /* page was already zeroed by PageInit, so this is not needed: */
+ /* memset(&(opaque->nsn), 0, sizeof(GistNSN)); */
+}
+
+/*
+ * Verify that a freshly-read page looks sane.
+ */
+void
+gistcheckpage(Relation rel, Buffer buf)
+{
+ Page page = BufferGetPage(buf);
+
+ /*
+ * ReadBuffer verifies that every newly-read page passes PageHeaderIsValid,
+ * which means it either contains a reasonably sane page header or is
+ * all-zero. We have to defend against the all-zero case, however.
+ */
+ if (PageIsNew(page))
+ ereport(ERROR,
+ (errcode(ERRCODE_INDEX_CORRUPTED),
+ errmsg("index \"%s\" contains unexpected zero page at block %u",
+ RelationGetRelationName(rel),
+ BufferGetBlockNumber(buf)),
+ errhint("Please REINDEX it.")));
+
+ /*
+ * Additionally check that the special area looks sane.
+ */
+ if (((PageHeader) (page))->pd_special !=
+ (BLCKSZ - MAXALIGN(sizeof(GISTPageOpaqueData))))
+ ereport(ERROR,
+ (errcode(ERRCODE_INDEX_CORRUPTED),
+ errmsg("index \"%s\" contains corrupted page at block %u",
+ RelationGetRelationName(rel),
+ BufferGetBlockNumber(buf)),
+ errhint("Please REINDEX it.")));
+}
+
+
+/*
+ * Allocate a new page (either by recycling, or by extending the index file)
+ *
+ * The returned buffer is already pinned and exclusive-locked
+ *
+ * Caller is responsible for initializing the page by calling GISTInitBuffer
+ */
Buffer
gistNewBuffer(Relation r)
{
- Buffer buffer = InvalidBuffer;
+ Buffer buffer;
bool needLock;
- while (true)
+ /* First, try to get a page from FSM */
+ for (;;)
{
BlockNumber blkno = GetFreeIndexPage(&r->rd_node);
if (blkno == InvalidBlockNumber)
- break;
+ break; /* nothing left in FSM */
buffer = ReadBuffer(r, blkno);
+ /*
+ * We have to guard against the possibility that someone else already
+ * recycled this page; the buffer may be locked if so.
+ */
if (ConditionalLockBuffer(buffer))
{
Page page = BufferGetPage(buffer);
+ if (PageIsNew(page))
+ return buffer; /* OK to use, if never initialized */
+
+ gistcheckpage(r, buffer);
+
if (GistPageIsDeleted(page))
- {
- GistPageSetNonDeleted(page);
- return buffer;
- }
- else
- LockBuffer(buffer, GIST_UNLOCK);
+ return buffer; /* OK to use */
+
+ LockBuffer(buffer, GIST_UNLOCK);
}
+ /* Can't use it, so release buffer and try again */
ReleaseBuffer(buffer);
}
+ /* Must extend the file */
needLock = !RELATION_IS_LOCAL(r);
if (needLock)
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/gist/gistvacuum.c,v 1.9 2005/09/22 20:44:36 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/gist/gistvacuum.c,v 1.10 2005/11/06 22:39:20 tgl Exp $
*
*-------------------------------------------------------------------------
*/
lencompleted = 16;
buffer = ReadBuffer(gv->index, blkno);
+ /*
+ * This is only used during VACUUM FULL, so we need not bother to lock
+ * individual index pages
+ */
+ gistcheckpage(gv->index, buffer);
page = (Page) BufferGetPage(buffer);
maxoff = PageGetMaxOffsetNumber(page);
needFullVacuum = false;
- needLock = !RELATION_IS_LOCAL(rel);
if (info->vacuum_full)
needLock = false; /* relation locked with AccessExclusiveLock */
+ else
+ needLock = !RELATION_IS_LOCAL(rel);
/* try to find deleted pages */
if (needLock)
LockBuffer(buffer, GIST_SHARE);
page = (Page) BufferGetPage(buffer);
- if (GistPageIsDeleted(page))
+ if (PageIsNew(page) || GistPageIsDeleted(page))
{
if (nFreePages < maxFreePages)
{
ItemId iid;
LockBuffer(buffer, GIST_SHARE);
+ gistcheckpage(rel, buffer);
page = (Page) BufferGetPage(buffer);
if (GistPageIsLeaf(page))
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/access/gist_private.h,v 1.8 2005/10/15 02:49:42 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/access/gist_private.h,v 1.9 2005/11/06 22:39:21 tgl Exp $
*
*-------------------------------------------------------------------------
*/
extern Datum gistgetmulti(PG_FUNCTION_ARGS);
/* gistutil.c */
+extern void gistcheckpage(Relation rel, Buffer buf);
extern Buffer gistNewBuffer(Relation r);
extern OffsetNumber gistfillbuffer(Relation r, Page page, IndexTuple *itup,
int len, OffsetNumber off);
projects / postgresql.git / commitdiff