From 375f441bd19c0e747affbaa8a40203428411f5df Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 21 Dec 2023 12:43:36 -0500 Subject: Avoid trying to fetch metapage of an SPGist partitioned index. This is necessary when spgcanreturn() is invoked on a partitioned index, and the failure might be reachable in other scenarios as well. The rest of what spgGetCache() does is perfectly sensible for a partitioned index, so we should allow it to go through. I think the main takeaway from this is that we lack sufficient test coverage for non-btree partitioned indexes. Therefore, I added simple test cases for brin and gin as well as spgist (hash and gist AMs were covered already in indexing.sql). Per bug #18256 from Alexander Lakhin. Although the known test case only fails since v16 (3c569049b), I've got no faith at all that there aren't other ways to reach this problem; so back-patch to all supported branches. Discussion: https://postgr.es/m/18256-0b0e1b6e4a620f1b@postgresql.org --- src/backend/access/spgist/spgutils.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-) (limited to 'src/backend/access/spgist/spgutils.c') diff --git a/src/backend/access/spgist/spgutils.c b/src/backend/access/spgist/spgutils.c index a76c52aa94c..d169369e337 100644 --- a/src/backend/access/spgist/spgutils.c +++ b/src/backend/access/spgist/spgutils.c @@ -185,8 +185,6 @@ spgGetCache(Relation index) Oid atttype; spgConfigIn in; FmgrInfo *procinfo; - Buffer metabuffer; - SpGistMetaPageData *metadata; cache = MemoryContextAllocZero(index->rd_indexcxt, sizeof(SpGistCache)); @@ -254,19 +252,28 @@ spgGetCache(Relation index) fillTypeDesc(&cache->attPrefixType, cache->config.prefixType); fillTypeDesc(&cache->attLabelType, cache->config.labelType); - /* Last, get the lastUsedPages data from the metapage */ - metabuffer = ReadBuffer(index, SPGIST_METAPAGE_BLKNO); - LockBuffer(metabuffer, BUFFER_LOCK_SHARE); + /* + * Finally, if it's a real index (not a partitioned one), get the + * lastUsedPages data from the metapage + */ + if (index->rd_rel->relkind != RELKIND_PARTITIONED_INDEX) + { + Buffer metabuffer; + SpGistMetaPageData *metadata; + + metabuffer = ReadBuffer(index, SPGIST_METAPAGE_BLKNO); + LockBuffer(metabuffer, BUFFER_LOCK_SHARE); - metadata = SpGistPageGetMeta(BufferGetPage(metabuffer)); + metadata = SpGistPageGetMeta(BufferGetPage(metabuffer)); - if (metadata->magicNumber != SPGIST_MAGIC_NUMBER) - elog(ERROR, "index \"%s\" is not an SP-GiST index", - RelationGetRelationName(index)); + if (metadata->magicNumber != SPGIST_MAGIC_NUMBER) + elog(ERROR, "index \"%s\" is not an SP-GiST index", + RelationGetRelationName(index)); - cache->lastUsedPages = metadata->lastUsedPages; + cache->lastUsedPages = metadata->lastUsedPages; - UnlockReleaseBuffer(metabuffer); + UnlockReleaseBuffer(metabuffer); + } index->rd_amcache = (void *) cache; } -- cgit v1.2.3