diff options
Diffstat (limited to 'src/backend/access/spgist/spgutils.c')
| -rw-r--r-- | src/backend/access/spgist/spgutils.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/src/backend/access/spgist/spgutils.c b/src/backend/access/spgist/spgutils.c index 22f64b0103c..bd5301f383a 100644 --- a/src/backend/access/spgist/spgutils.c +++ b/src/backend/access/spgist/spgutils.c @@ -256,15 +256,27 @@ SpGistUpdateMetaPage(Relation index) if (cache != NULL) { Buffer metabuffer; - SpGistMetaPageData *metadata; metabuffer = ReadBuffer(index, SPGIST_METAPAGE_BLKNO); if (ConditionalLockBuffer(metabuffer)) { - metadata = SpGistPageGetMeta(BufferGetPage(metabuffer)); + Page metapage = BufferGetPage(metabuffer); + SpGistMetaPageData *metadata = SpGistPageGetMeta(metapage); + metadata->lastUsedPages = cache->lastUsedPages; + /* + * Set pd_lower just past the end of the metadata. This is + * essential, because without doing so, metadata will be lost if + * xlog.c compresses the page. (We must do this here because + * pre-v11 versions of PG did not set the metapage's pd_lower + * correctly, so a pg_upgraded index might contain the wrong + * value.) + */ + ((PageHeader) metapage)->pd_lower = + ((char *) metadata + sizeof(SpGistMetaPageData)) - (char *) metapage; + MarkBufferDirty(metabuffer); UnlockReleaseBuffer(metabuffer); } @@ -534,6 +546,14 @@ SpGistInitMetapage(Page page) /* initialize last-used-page cache to empty */ for (i = 0; i < SPGIST_CACHED_PAGES; i++) metadata->lastUsedPages.cachedPage[i].blkno = InvalidBlockNumber; + + /* + * Set pd_lower just past the end of the metadata. This is essential, + * because without doing so, metadata will be lost if xlog.c compresses + * the page. + */ + ((PageHeader) page)->pd_lower = + ((char *) metadata + sizeof(SpGistMetaPageData)) - (char *) page; } /* |