Fix checksum calculation in the new sorting GiST build.

Since we're bypassing the buffer manager, we need to call
PageSetChecksumInplace() directly. As reported by Justin Pryzby.

In the passing, add RelationOpenSmgr() calls before all smgrwrite() and
smgrextend() calls. Tom added one before the first smgrextend() call in
commit c2bb287025, which seems to be enough, but let's play it safe and
do it before each one. That's how it's done in the similar code in
nbtsort.c, too.

Discussion: https://www.postgresql.org/message-id/20200920224446[email protected]

diff --git a/src/backend/access/gist/gistbuild.c b/src/backend/access/gist/gistbuild.c
index 5ecc4c87d11940545f77db1cc2025b9a6d3a12b1..188e33642f3db009dbd5f5372e2aa3c44ab9ee50 100644 (file)
--- a/src/backend/access/gist/gistbuild.c
+++ b/src/backend/access/gist/gistbuild.c
@@ -449,7 +449,9 @@ gist_indexsortbuild(GISTBuildState *state)
    gist_indexsortbuild_flush_ready_pages(state);
 
    /* Write out the root */
+   RelationOpenSmgr(state->indexrel);
    PageSetLSN(pagestate->page, GistBuildLSN);
+   PageSetChecksumInplace(pagestate->page, GIST_ROOT_BLKNO);
    smgrwrite(state->indexrel->rd_smgr, MAIN_FORKNUM, GIST_ROOT_BLKNO,
              pagestate->page, true);
    if (RelationNeedsWAL(state->indexrel))
@@ -546,21 +548,22 @@ gist_indexsortbuild_flush_ready_pages(GISTBuildState *state)
    if (state->ready_num_pages == 0)
        return;
 
+   RelationOpenSmgr(state->indexrel);
+
    for (int i = 0; i < state->ready_num_pages; i++)
    {
        Page        page = state->ready_pages[i];
+       BlockNumber blkno = state->ready_blknos[i];
 
        /* Currently, the blocks must be buffered in order. */
-       if (state->ready_blknos[i] != state->pages_written)
+       if (blkno != state->pages_written)
            elog(ERROR, "unexpected block number to flush GiST sorting build");
 
        PageSetLSN(page, GistBuildLSN);
+       PageSetChecksumInplace(page, blkno);
+       smgrextend(state->indexrel->rd_smgr, MAIN_FORKNUM, blkno, page, true);
 
-       smgrextend(state->indexrel->rd_smgr,
-                  MAIN_FORKNUM,
-                  state->pages_written++,
-                  page,
-                  true);
+       state->pages_written++;
    }
 
    if (RelationNeedsWAL(state->indexrel))