pageinspect: Fix memory context allocation of page in brin_revmap_data()

This caused the function to fail, as the aligned copy of the raw page
given by the function caller was not saved in the correct memory
context, which needs to be multi_call_memory_ctx in this case.

Issue introduced by 076f4d9.

Per buildfarm members sifika, mylodon and longfin.  I have reproduced
that locally with macos.

Discussion: https://postgr.es/m/[email protected]
Backpatch-through: 10

diff --git a/contrib/pageinspect/brinfuncs.c b/contrib/pageinspect/brinfuncs.c
index ddf1380d74125d90f4095714b963de5c8673248a..ca9ece64d2ed68010fbc2f24506399fce56d7fd9 100644 (file)
--- a/contrib/pageinspect/brinfuncs.c
+++ b/contrib/pageinspect/brinfuncs.c
@@ -383,15 +383,15 @@ brin_revmap_data(PG_FUNCTION_ARGS)
        MemoryContext mctx;
        Page        page;
 
-       /* minimally verify the page we got */
-       page = verify_brin_page(raw_page, BRIN_PAGETYPE_REVMAP, "revmap");
-
        /* create a function context for cross-call persistence */
        fctx = SRF_FIRSTCALL_INIT();
 
        /* switch to memory context appropriate for multiple function calls */
        mctx = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);
 
+       /* minimally verify the page we got */
+       page = verify_brin_page(raw_page, BRIN_PAGETYPE_REVMAP, "revmap");
+
        state = palloc(sizeof(*state));
        state->tids = ((RevmapContents *) PageGetContents(page))->rm_tids;
        state->idx = 0;