From 9a299cf7c21f30ca5d045faaf725e8216d3cc5f5 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 17 Nov 2022 16:54:30 -0500 Subject: [PATCH] Replace RelationOpenSmgr() with RelationGetSmgr(). This is a back-patch of the v15-era commit f10f0ae42 into older supported branches. The idea is to design out bugs in which an ill-timed relcache flush clears rel->rd_smgr partway through some code sequence that wasn't expecting that. We had another report today of a corner case that reliably crashes v14 under debug_discard_caches (nee CLOBBER_CACHE_ALWAYS), and therefore would crash once in a blue moon in the field. We're unlikely to get rid of all such code paths unless we adopt the more rigorous coding rules instituted by f10f0ae42. Therefore, even though this is a bit invasive, it's time to back-patch. Some comfort can be taken in the fact that f10f0ae42 has been in v15 for 16 months without problems. I left the RelationOpenSmgr macro present in the back branches, even though no core code should use it anymore, in order to not break third-party extensions in minor releases. Such extensions might opt to start using RelationGetSmgr instead, to reduce their code differential between v15 and earlier branches. This carries a hazard of failing to compile against headers from existing minor releases. However, once compiled the extension should work fine even with such releases, because RelationGetSmgr is a "static inline" function so it creates no link-time dependency. So depending on distribution practices, that might be an OK tradeoff. Per report from Spyridon Dimitrios Agathos. Original patch by Amul Sul. Discussion: https://postgr.es/m/CAFM5RaqdgyusQvmWkyPYaWMwoK5gigdtW-7HcgHgOeAw7mqJ_Q@mail.gmail.com Discussion: https://postgr.es/m/CANiYTQsU7yMFpQYnv=BrcRVqK_3U3mtAzAsJCaqtzsDHfsUbdQ@mail.gmail.com --- contrib/amcheck/verify_nbtree.c | 3 +- contrib/bloom/blinsert.c | 6 +-- contrib/pg_prewarm/autoprewarm.c | 4 +- contrib/pg_prewarm/pg_prewarm.c | 5 +-- contrib/pg_visibility/pg_visibility.c | 6 +-- src/backend/access/gist/gistbuild.c | 2 +- src/backend/access/hash/hashpage.c | 4 +- src/backend/access/heap/heapam_handler.c | 7 ++- src/backend/access/heap/rewriteheap.c | 15 ++----- src/backend/access/heap/visibilitymap.c | 54 ++++++++++++----------- src/backend/access/nbtree/nbtree.c | 6 +-- src/backend/access/nbtree/nbtsort.c | 14 ++---- src/backend/access/spgist/spginsert.c | 14 +++--- src/backend/access/table/tableam.c | 7 +-- src/backend/catalog/heap.c | 2 - src/backend/catalog/index.c | 5 +-- src/backend/catalog/storage.c | 48 +++++++++++++------- src/backend/commands/tablecmds.c | 7 ++- src/backend/storage/buffer/bufmgr.c | 24 +++------- src/backend/storage/freespace/freespace.c | 51 ++++++++++++--------- src/include/utils/rel.h | 34 +++++++++++--- 21 files changed, 166 insertions(+), 152 deletions(-) diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c index e857dc3addc..63d1f0df4dc 100644 --- a/contrib/amcheck/verify_nbtree.c +++ b/contrib/amcheck/verify_nbtree.c @@ -319,8 +319,7 @@ bt_index_check_internal(Oid indrelid, bool parentcheck, bool heapallindexed, bool heapkeyspace, allequalimage; - RelationOpenSmgr(indrel); - if (!smgrexists(indrel->rd_smgr, MAIN_FORKNUM)) + if (!smgrexists(RelationGetSmgr(indrel), MAIN_FORKNUM)) ereport(ERROR, (errcode(ERRCODE_INDEX_CORRUPTED), errmsg("index \"%s\" lacks a main relation fork", diff --git a/contrib/bloom/blinsert.c b/contrib/bloom/blinsert.c index 6d3fd5c432c..00f808688f4 100644 --- a/contrib/bloom/blinsert.c +++ b/contrib/bloom/blinsert.c @@ -178,9 +178,9 @@ blbuildempty(Relation index) * this even when wal_level=minimal. */ PageSetChecksumInplace(metapage, BLOOM_METAPAGE_BLKNO); - smgrwrite(index->rd_smgr, INIT_FORKNUM, BLOOM_METAPAGE_BLKNO, + smgrwrite(RelationGetSmgr(index), INIT_FORKNUM, BLOOM_METAPAGE_BLKNO, (char *) metapage, true); - log_newpage(&index->rd_smgr->smgr_rnode.node, INIT_FORKNUM, + log_newpage(&(RelationGetSmgr(index))->smgr_rnode.node, INIT_FORKNUM, BLOOM_METAPAGE_BLKNO, metapage, true); /* @@ -188,7 +188,7 @@ blbuildempty(Relation index) * write did not go through shared_buffers and therefore a concurrent * checkpoint may have moved the redo pointer past our xlog record. */ - smgrimmedsync(index->rd_smgr, INIT_FORKNUM); + smgrimmedsync(RelationGetSmgr(index), INIT_FORKNUM); } /* diff --git a/contrib/pg_prewarm/autoprewarm.c b/contrib/pg_prewarm/autoprewarm.c index 1701da9dff4..31be24fc9c3 100644 --- a/contrib/pg_prewarm/autoprewarm.c +++ b/contrib/pg_prewarm/autoprewarm.c @@ -518,15 +518,13 @@ autoprewarm_database_main(Datum main_arg) old_blk->filenode != blk->filenode || old_blk->forknum != blk->forknum) { - RelationOpenSmgr(rel); - /* * smgrexists is not safe for illegal forknum, hence check whether * the passed forknum is valid before using it in smgrexists. */ if (blk->forknum > InvalidForkNumber && blk->forknum <= MAX_FORKNUM && - smgrexists(rel->rd_smgr, blk->forknum)) + smgrexists(RelationGetSmgr(rel), blk->forknum)) nblocks = RelationGetNumberOfBlocksInFork(rel, blk->forknum); else nblocks = 0; diff --git a/contrib/pg_prewarm/pg_prewarm.c b/contrib/pg_prewarm/pg_prewarm.c index 33e2d28b276..0d1d2b24bdb 100644 --- a/contrib/pg_prewarm/pg_prewarm.c +++ b/contrib/pg_prewarm/pg_prewarm.c @@ -109,8 +109,7 @@ pg_prewarm(PG_FUNCTION_ARGS) aclcheck_error(aclresult, get_relkind_objtype(rel->rd_rel->relkind), get_rel_name(relOid)); /* Check that the fork exists. */ - RelationOpenSmgr(rel); - if (!smgrexists(rel->rd_smgr, forkNumber)) + if (!smgrexists(RelationGetSmgr(rel), forkNumber)) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("fork \"%s\" does not exist for this relation", @@ -178,7 +177,7 @@ pg_prewarm(PG_FUNCTION_ARGS) for (block = first_block; block <= last_block; ++block) { CHECK_FOR_INTERRUPTS(); - smgrread(rel->rd_smgr, forkNumber, block, blockbuffer.data); + smgrread(RelationGetSmgr(rel), forkNumber, block, blockbuffer.data); ++blocks_done; } } diff --git a/contrib/pg_visibility/pg_visibility.c b/contrib/pg_visibility/pg_visibility.c index 68d580ed1e0..bb6dc380370 100644 --- a/contrib/pg_visibility/pg_visibility.c +++ b/contrib/pg_visibility/pg_visibility.c @@ -391,14 +391,14 @@ pg_truncate_visibility_map(PG_FUNCTION_ARGS) /* Only some relkinds have a visibility map */ check_relation_relkind(rel); - RelationOpenSmgr(rel); - rel->rd_smgr->smgr_vm_nblocks = InvalidBlockNumber; + /* Forcibly reset cached file size */ + RelationGetSmgr(rel)->smgr_vm_nblocks = InvalidBlockNumber; block = visibilitymap_prepare_truncate(rel, 0); if (BlockNumberIsValid(block)) { fork = VISIBILITYMAP_FORKNUM; - smgrtruncate(rel->rd_smgr, &fork, 1, &block); + smgrtruncate(RelationGetSmgr(rel), &fork, 1, &block); } if (RelationNeedsWAL(rel)) diff --git a/src/backend/access/gist/gistbuild.c b/src/backend/access/gist/gistbuild.c index 671b5e9186f..25b5d81cd67 100644 --- a/src/backend/access/gist/gistbuild.c +++ b/src/backend/access/gist/gistbuild.c @@ -495,7 +495,7 @@ gistBuildCallback(Relation index, */ if ((buildstate->bufferingMode == GIST_BUFFERING_AUTO && buildstate->indtuples % BUFFERING_MODE_SWITCH_CHECK_STEP == 0 && - effective_cache_size < smgrnblocks(index->rd_smgr, MAIN_FORKNUM)) || + effective_cache_size < smgrnblocks(RelationGetSmgr(index), MAIN_FORKNUM)) || (buildstate->bufferingMode == GIST_BUFFERING_STATS && buildstate->indtuples >= BUFFERING_MODE_TUPLE_SIZE_STATS_TARGET)) { diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c index 1e6cf49fb18..6ac53579cdb 100644 --- a/src/backend/access/hash/hashpage.c +++ b/src/backend/access/hash/hashpage.c @@ -1028,9 +1028,9 @@ _hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks) zerobuf.data, true); - RelationOpenSmgr(rel); PageSetChecksumInplace(page, lastblock); - smgrextend(rel->rd_smgr, MAIN_FORKNUM, lastblock, zerobuf.data, false); + smgrextend(RelationGetSmgr(rel), MAIN_FORKNUM, lastblock, zerobuf.data, + false); return true; } diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c index b772f713233..8b0e5eb2d79 100644 --- a/src/backend/access/heap/heapam_handler.c +++ b/src/backend/access/heap/heapam_handler.c @@ -626,7 +626,6 @@ heapam_relation_copy_data(Relation rel, const RelFileNode *newrnode) SMgrRelation dstrel; dstrel = smgropen(*newrnode, rel->rd_backend); - RelationOpenSmgr(rel); /* * Since we copy the file directly without looking at the shared buffers, @@ -646,14 +645,14 @@ heapam_relation_copy_data(Relation rel, const RelFileNode *newrnode) RelationCreateStorage(*newrnode, rel->rd_rel->relpersistence); /* copy main fork */ - RelationCopyStorage(rel->rd_smgr, dstrel, MAIN_FORKNUM, + RelationCopyStorage(RelationGetSmgr(rel), dstrel, MAIN_FORKNUM, rel->rd_rel->relpersistence); /* copy those extra forks that exist */ for (ForkNumber forkNum = MAIN_FORKNUM + 1; forkNum <= MAX_FORKNUM; forkNum++) { - if (smgrexists(rel->rd_smgr, forkNum)) + if (smgrexists(RelationGetSmgr(rel), forkNum)) { smgrcreate(dstrel, forkNum, false); @@ -665,7 +664,7 @@ heapam_relation_copy_data(Relation rel, const RelFileNode *newrnode) (rel->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED && forkNum == INIT_FORKNUM)) log_smgrcreate(newrnode, forkNum); - RelationCopyStorage(rel->rd_smgr, dstrel, forkNum, + RelationCopyStorage(RelationGetSmgr(rel), dstrel, forkNum, rel->rd_rel->relpersistence); } } diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c index 39748bbd85b..6aae7df2e73 100644 --- a/src/backend/access/heap/rewriteheap.c +++ b/src/backend/access/heap/rewriteheap.c @@ -327,9 +327,8 @@ end_heap_rewrite(RewriteState state) PageSetChecksumInplace(state->rs_buffer, state->rs_blockno); - RelationOpenSmgr(state->rs_new_rel); - smgrextend(state->rs_new_rel->rd_smgr, MAIN_FORKNUM, state->rs_blockno, - (char *) state->rs_buffer, true); + smgrextend(RelationGetSmgr(state->rs_new_rel), MAIN_FORKNUM, + state->rs_blockno, (char *) state->rs_buffer, true); } /* @@ -340,11 +339,7 @@ end_heap_rewrite(RewriteState state) * wrote before the checkpoint. */ if (RelationNeedsWAL(state->rs_new_rel)) - { - /* for an empty table, this could be first smgr access */ - RelationOpenSmgr(state->rs_new_rel); - smgrimmedsync(state->rs_new_rel->rd_smgr, MAIN_FORKNUM); - } + smgrimmedsync(RelationGetSmgr(state->rs_new_rel), MAIN_FORKNUM); logical_end_heap_rewrite(state); @@ -692,11 +687,9 @@ raw_heap_insert(RewriteState state, HeapTuple tup) * need for smgr to schedule an fsync for this write; we'll do it * ourselves in end_heap_rewrite. */ - RelationOpenSmgr(state->rs_new_rel); - PageSetChecksumInplace(page, state->rs_blockno); - smgrextend(state->rs_new_rel->rd_smgr, MAIN_FORKNUM, + smgrextend(RelationGetSmgr(state->rs_new_rel), MAIN_FORKNUM, state->rs_blockno, (char *) page, true); state->rs_blockno++; diff --git a/src/backend/access/heap/visibilitymap.c b/src/backend/access/heap/visibilitymap.c index 0a51678c40d..6a14039ea7b 100644 --- a/src/backend/access/heap/visibilitymap.c +++ b/src/backend/access/heap/visibilitymap.c @@ -455,13 +455,11 @@ visibilitymap_prepare_truncate(Relation rel, BlockNumber nheapblocks) elog(DEBUG1, "vm_truncate %s %d", RelationGetRelationName(rel), nheapblocks); #endif - RelationOpenSmgr(rel); - /* * If no visibility map has been created yet for this relation, there's * nothing to truncate. */ - if (!smgrexists(rel->rd_smgr, VISIBILITYMAP_FORKNUM)) + if (!smgrexists(RelationGetSmgr(rel), VISIBILITYMAP_FORKNUM)) return InvalidBlockNumber; /* @@ -528,7 +526,7 @@ visibilitymap_prepare_truncate(Relation rel, BlockNumber nheapblocks) else newnblocks = truncBlock; - if (smgrnblocks(rel->rd_smgr, VISIBILITYMAP_FORKNUM) <= newnblocks) + if (smgrnblocks(RelationGetSmgr(rel), VISIBILITYMAP_FORKNUM) <= newnblocks) { /* nothing to do, the file was already smaller than requested size */ return InvalidBlockNumber; @@ -547,31 +545,30 @@ static Buffer vm_readbuf(Relation rel, BlockNumber blkno, bool extend) { Buffer buf; + SMgrRelation reln; /* - * We might not have opened the relation at the smgr level yet, or we - * might have been forced to close it by a sinval message. The code below - * won't necessarily notice relation extension immediately when extend = - * false, so we rely on sinval messages to ensure that our ideas about the - * size of the map aren't too far out of date. + * Caution: re-using this smgr pointer could fail if the relcache entry + * gets closed. It's safe as long as we only do smgr-level operations + * between here and the last use of the pointer. */ - RelationOpenSmgr(rel); + reln = RelationGetSmgr(rel); /* * If we haven't cached the size of the visibility map fork yet, check it * first. */ - if (rel->rd_smgr->smgr_vm_nblocks == InvalidBlockNumber) + if (reln->smgr_vm_nblocks == InvalidBlockNumber) { - if (smgrexists(rel->rd_smgr, VISIBILITYMAP_FORKNUM)) - rel->rd_smgr->smgr_vm_nblocks = smgrnblocks(rel->rd_smgr, - VISIBILITYMAP_FORKNUM); + if (smgrexists(reln, VISIBILITYMAP_FORKNUM)) + reln->smgr_vm_nblocks = smgrnblocks(reln, + VISIBILITYMAP_FORKNUM); else - rel->rd_smgr->smgr_vm_nblocks = 0; + reln->smgr_vm_nblocks = 0; } /* Handle requests beyond EOF */ - if (blkno >= rel->rd_smgr->smgr_vm_nblocks) + if (blkno >= reln->smgr_vm_nblocks) { if (extend) vm_extend(rel, blkno + 1); @@ -619,6 +616,7 @@ vm_extend(Relation rel, BlockNumber vm_nblocks) { BlockNumber vm_nblocks_now; PGAlignedBlock pg; + SMgrRelation reln; PageInit((Page) pg.data, BLCKSZ, 0); @@ -634,26 +632,30 @@ vm_extend(Relation rel, BlockNumber vm_nblocks) */ LockRelationForExtension(rel, ExclusiveLock); - /* Might have to re-open if a cache flush happened */ - RelationOpenSmgr(rel); + /* + * Caution: re-using this smgr pointer could fail if the relcache entry + * gets closed. It's safe as long as we only do smgr-level operations + * between here and the last use of the pointer. + */ + reln = RelationGetSmgr(rel); /* * Create the file first if it doesn't exist. If smgr_vm_nblocks is * positive then it must exist, no need for an smgrexists call. */ - if ((rel->rd_smgr->smgr_vm_nblocks == 0 || - rel->rd_smgr->smgr_vm_nblocks == InvalidBlockNumber) && - !smgrexists(rel->rd_smgr, VISIBILITYMAP_FORKNUM)) - smgrcreate(rel->rd_smgr, VISIBILITYMAP_FORKNUM, false); + if ((reln->smgr_vm_nblocks == 0 || + reln->smgr_vm_nblocks == InvalidBlockNumber) && + !smgrexists(reln, VISIBILITYMAP_FORKNUM)) + smgrcreate(reln, VISIBILITYMAP_FORKNUM, false); - vm_nblocks_now = smgrnblocks(rel->rd_smgr, VISIBILITYMAP_FORKNUM); + vm_nblocks_now = smgrnblocks(reln, VISIBILITYMAP_FORKNUM); /* Now extend the file */ while (vm_nblocks_now < vm_nblocks) { PageSetChecksumInplace((Page) pg.data, vm_nblocks_now); - smgrextend(rel->rd_smgr, VISIBILITYMAP_FORKNUM, vm_nblocks_now, + smgrextend(reln, VISIBILITYMAP_FORKNUM, vm_nblocks_now, pg.data, false); vm_nblocks_now++; } @@ -665,10 +667,10 @@ vm_extend(Relation rel, BlockNumber vm_nblocks) * to keep checking for creation or extension of the file, which happens * infrequently. */ - CacheInvalidateSmgr(rel->rd_smgr->smgr_rnode); + CacheInvalidateSmgr(reln->smgr_rnode); /* Update local cache with the up-to-date size */ - rel->rd_smgr->smgr_vm_nblocks = vm_nblocks_now; + reln->smgr_vm_nblocks = vm_nblocks_now; UnlockRelationForExtension(rel, ExclusiveLock); } diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c index c37bbe53f98..e8c87e1edf2 100644 --- a/src/backend/access/nbtree/nbtree.c +++ b/src/backend/access/nbtree/nbtree.c @@ -175,9 +175,9 @@ btbuildempty(Relation index) * this even when wal_level=minimal. */ PageSetChecksumInplace(metapage, BTREE_METAPAGE); - smgrwrite(index->rd_smgr, INIT_FORKNUM, BTREE_METAPAGE, + smgrwrite(RelationGetSmgr(index), INIT_FORKNUM, BTREE_METAPAGE, (char *) metapage, true); - log_newpage(&index->rd_smgr->smgr_rnode.node, INIT_FORKNUM, + log_newpage(&RelationGetSmgr(index)->smgr_rnode.node, INIT_FORKNUM, BTREE_METAPAGE, metapage, true); /* @@ -185,7 +185,7 @@ btbuildempty(Relation index) * write did not go through shared_buffers and therefore a concurrent * checkpoint may have moved the redo pointer past our xlog record. */ - smgrimmedsync(index->rd_smgr, INIT_FORKNUM); + smgrimmedsync(RelationGetSmgr(index), INIT_FORKNUM); } /* diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index bde61b7c5f0..315889a791e 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -638,9 +638,6 @@ _bt_blnewpage(uint32 level) static void _bt_blwritepage(BTWriteState *wstate, Page page, BlockNumber blkno) { - /* Ensure rd_smgr is open (could have been closed by relcache flush!) */ - RelationOpenSmgr(wstate->index); - /* XLOG stuff */ if (wstate->btws_use_wal) { @@ -660,7 +657,7 @@ _bt_blwritepage(BTWriteState *wstate, Page page, BlockNumber blkno) if (!wstate->btws_zeropage) wstate->btws_zeropage = (Page) palloc0(BLCKSZ); /* don't set checksum for all-zero page */ - smgrextend(wstate->index->rd_smgr, MAIN_FORKNUM, + smgrextend(RelationGetSmgr(wstate->index), MAIN_FORKNUM, wstate->btws_pages_written++, (char *) wstate->btws_zeropage, true); @@ -675,14 +672,14 @@ _bt_blwritepage(BTWriteState *wstate, Page page, BlockNumber blkno) if (blkno == wstate->btws_pages_written) { /* extending the file... */ - smgrextend(wstate->index->rd_smgr, MAIN_FORKNUM, blkno, + smgrextend(RelationGetSmgr(wstate->index), MAIN_FORKNUM, blkno, (char *) page, true); wstate->btws_pages_written++; } else { /* overwriting a block we zero-filled before */ - smgrwrite(wstate->index->rd_smgr, MAIN_FORKNUM, blkno, + smgrwrite(RelationGetSmgr(wstate->index), MAIN_FORKNUM, blkno, (char *) page, true); } @@ -1428,10 +1425,7 @@ _bt_load(BTWriteState *wstate, BTSpool *btspool, BTSpool *btspool2) * still not be on disk when the crash occurs. */ if (wstate->btws_use_wal) - { - RelationOpenSmgr(wstate->index); - smgrimmedsync(wstate->index->rd_smgr, MAIN_FORKNUM); - } + smgrimmedsync(RelationGetSmgr(wstate->index), MAIN_FORKNUM); } /* diff --git a/src/backend/access/spgist/spginsert.c b/src/backend/access/spgist/spginsert.c index e4508a2b923..5a579354b78 100644 --- a/src/backend/access/spgist/spginsert.c +++ b/src/backend/access/spgist/spginsert.c @@ -169,27 +169,27 @@ spgbuildempty(Relation index) * replayed. */ PageSetChecksumInplace(page, SPGIST_METAPAGE_BLKNO); - smgrwrite(index->rd_smgr, INIT_FORKNUM, SPGIST_METAPAGE_BLKNO, + smgrwrite(RelationGetSmgr(index), INIT_FORKNUM, SPGIST_METAPAGE_BLKNO, (char *) page, true); - log_newpage(&index->rd_smgr->smgr_rnode.node, INIT_FORKNUM, + log_newpage(&(RelationGetSmgr(index))->smgr_rnode.node, INIT_FORKNUM, SPGIST_METAPAGE_BLKNO, page, true); /* Likewise for the root page. */ SpGistInitPage(page, SPGIST_LEAF); PageSetChecksumInplace(page, SPGIST_ROOT_BLKNO); - smgrwrite(index->rd_smgr, INIT_FORKNUM, SPGIST_ROOT_BLKNO, + smgrwrite(RelationGetSmgr(index), INIT_FORKNUM, SPGIST_ROOT_BLKNO, (char *) page, true); - log_newpage(&index->rd_smgr->smgr_rnode.node, INIT_FORKNUM, + log_newpage(&(RelationGetSmgr(index))->smgr_rnode.node, INIT_FORKNUM, SPGIST_ROOT_BLKNO, page, true); /* Likewise for the null-tuples root page. */ SpGistInitPage(page, SPGIST_LEAF | SPGIST_NULLS); PageSetChecksumInplace(page, SPGIST_NULL_BLKNO); - smgrwrite(index->rd_smgr, INIT_FORKNUM, SPGIST_NULL_BLKNO, + smgrwrite(RelationGetSmgr(index), INIT_FORKNUM, SPGIST_NULL_BLKNO, (char *) page, true); - log_newpage(&index->rd_smgr->smgr_rnode.node, INIT_FORKNUM, + log_newpage(&(RelationGetSmgr(index))->smgr_rnode.node, INIT_FORKNUM, SPGIST_NULL_BLKNO, page, true); /* @@ -197,7 +197,7 @@ spgbuildempty(Relation index) * writes did not go through shared buffers and therefore a concurrent * checkpoint may have moved the redo pointer past our xlog record. */ - smgrimmedsync(index->rd_smgr, INIT_FORKNUM); + smgrimmedsync(RelationGetSmgr(index), INIT_FORKNUM); } /* diff --git a/src/backend/access/table/tableam.c b/src/backend/access/table/tableam.c index 4b2bb29559a..4e43813530f 100644 --- a/src/backend/access/table/tableam.c +++ b/src/backend/access/table/tableam.c @@ -513,17 +513,14 @@ table_block_relation_size(Relation rel, ForkNumber forkNumber) { uint64 nblocks = 0; - /* Open it at the smgr level if not already done */ - RelationOpenSmgr(rel); - /* InvalidForkNumber indicates returning the size for all forks */ if (forkNumber == InvalidForkNumber) { for (int i = 0; i < MAX_FORKNUM; i++) - nblocks += smgrnblocks(rel->rd_smgr, i); + nblocks += smgrnblocks(RelationGetSmgr(rel), i); } else - nblocks = smgrnblocks(rel->rd_smgr, forkNumber); + nblocks = smgrnblocks(RelationGetSmgr(rel), forkNumber); return nblocks * BLCKSZ; } diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c index a42070fd925..fa24be1a320 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -413,8 +413,6 @@ heap_create(const char *relname, */ if (create_storage) { - RelationOpenSmgr(rel); - switch (rel->rd_rel->relkind) { case RELKIND_VIEW: diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c index 602b51a6a79..64a45f4ed4a 100644 --- a/src/backend/catalog/index.c +++ b/src/backend/catalog/index.c @@ -3010,10 +3010,9 @@ index_build(Relation heapRelation, * relfilenode won't change, and nothing needs to be done here. */ if (indexRelation->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED && - !smgrexists(indexRelation->rd_smgr, INIT_FORKNUM)) + !smgrexists(RelationGetSmgr(indexRelation), INIT_FORKNUM)) { - RelationOpenSmgr(indexRelation); - smgrcreate(indexRelation->rd_smgr, INIT_FORKNUM, false); + smgrcreate(RelationGetSmgr(indexRelation), INIT_FORKNUM, false); indexRelation->rd_indam->ambuildempty(indexRelation); } diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c index d7c74105a4e..b823f508084 100644 --- a/src/backend/catalog/storage.c +++ b/src/backend/catalog/storage.c @@ -282,16 +282,16 @@ RelationTruncate(Relation rel, BlockNumber nblocks) ForkNumber forks[MAX_FORKNUM]; BlockNumber blocks[MAX_FORKNUM]; int nforks = 0; - - /* Open it at the smgr level if not already done */ - RelationOpenSmgr(rel); + SMgrRelation reln; /* - * Make sure smgr_targblock etc aren't pointing somewhere past new end + * Make sure smgr_targblock etc aren't pointing somewhere past new end. + * (Note: don't rely on this reln pointer below here.) */ - rel->rd_smgr->smgr_targblock = InvalidBlockNumber; - rel->rd_smgr->smgr_fsm_nblocks = InvalidBlockNumber; - rel->rd_smgr->smgr_vm_nblocks = InvalidBlockNumber; + reln = RelationGetSmgr(rel); + reln->smgr_targblock = InvalidBlockNumber; + reln->smgr_fsm_nblocks = InvalidBlockNumber; + reln->smgr_vm_nblocks = InvalidBlockNumber; /* Prepare for truncation of MAIN fork of the relation */ forks[nforks] = MAIN_FORKNUM; @@ -299,7 +299,7 @@ RelationTruncate(Relation rel, BlockNumber nblocks) nforks++; /* Prepare for truncation of the FSM if it exists */ - fsm = smgrexists(rel->rd_smgr, FSM_FORKNUM); + fsm = smgrexists(RelationGetSmgr(rel), FSM_FORKNUM); if (fsm) { blocks[nforks] = FreeSpaceMapPrepareTruncateRel(rel, nblocks); @@ -312,7 +312,7 @@ RelationTruncate(Relation rel, BlockNumber nblocks) } /* Prepare for truncation of the visibility map too if it exists */ - vm = smgrexists(rel->rd_smgr, VISIBILITYMAP_FORKNUM); + vm = smgrexists(RelationGetSmgr(rel), VISIBILITYMAP_FORKNUM); if (vm) { blocks[nforks] = visibilitymap_prepare_truncate(rel, nblocks); @@ -384,7 +384,7 @@ RelationTruncate(Relation rel, BlockNumber nblocks) * longer exist after truncation is complete, and then truncate the * corresponding files on disk. */ - smgrtruncate(rel->rd_smgr, forks, nforks, blocks); + smgrtruncate(RelationGetSmgr(rel), forks, nforks, blocks); /* We've done all the critical work, so checkpoints are OK now. */ MyProc->delayChkptEnd = false; @@ -416,9 +416,9 @@ RelationPreTruncate(Relation rel) if (!pendingSyncHash) return; - RelationOpenSmgr(rel); - pending = hash_search(pendingSyncHash, &(rel->rd_smgr->smgr_rnode.node), + pending = hash_search(pendingSyncHash, + &(RelationGetSmgr(rel)->smgr_rnode.node), HASH_FIND, NULL); if (pending) pending->is_truncated = true; @@ -430,6 +430,12 @@ RelationPreTruncate(Relation rel) * Note that this requires that there is no dirty data in shared buffers. If * it's possible that there are, callers need to flush those using * e.g. FlushRelationBuffers(rel). + * + * Also note that this is frequently called via locutions such as + * RelationCopyStorage(RelationGetSmgr(rel), ...); + * That's safe only because we perform only smgr and WAL operations here. + * If we invoked anything else, a relcache flush could cause our SMgrRelation + * argument to become a dangling pointer. */ void RelationCopyStorage(SMgrRelation src, SMgrRelation dst, @@ -472,13 +478,23 @@ RelationCopyStorage(SMgrRelation src, SMgrRelation dst, if (!PageIsVerifiedExtended(page, blkno, PIV_LOG_WARNING | PIV_REPORT_STAT)) + { + /* + * For paranoia's sake, capture the file path before invoking the + * ereport machinery. This guards against the possibility of a + * relcache flush caused by, e.g., an errcontext callback. + * (errcontext callbacks shouldn't be risking any such thing, but + * people have been known to forget that rule.) + */ + char *relpath = relpathbackend(src->smgr_rnode.node, + src->smgr_rnode.backend, + forkNum); + ereport(ERROR, (errcode(ERRCODE_DATA_CORRUPTED), errmsg("invalid page in block %u of relation %s", - blkno, - relpathbackend(src->smgr_rnode.node, - src->smgr_rnode.backend, - forkNum)))); + blkno, relpath))); + } /* * WAL-log the copied page. Unfortunately we don't know what kind of a diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 425630228f4..bcc7d3c29c4 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -13798,7 +13798,6 @@ index_copy_data(Relation rel, RelFileNode newrnode) SMgrRelation dstrel; dstrel = smgropen(newrnode, rel->rd_backend); - RelationOpenSmgr(rel); /* * Since we copy the file directly without looking at the shared buffers, @@ -13818,14 +13817,14 @@ index_copy_data(Relation rel, RelFileNode newrnode) RelationCreateStorage(newrnode, rel->rd_rel->relpersistence); /* copy main fork */ - RelationCopyStorage(rel->rd_smgr, dstrel, MAIN_FORKNUM, + RelationCopyStorage(RelationGetSmgr(rel), dstrel, MAIN_FORKNUM, rel->rd_rel->relpersistence); /* copy those extra forks that exist */ for (ForkNumber forkNum = MAIN_FORKNUM + 1; forkNum <= MAX_FORKNUM; forkNum++) { - if (smgrexists(rel->rd_smgr, forkNum)) + if (smgrexists(RelationGetSmgr(rel), forkNum)) { smgrcreate(dstrel, forkNum, false); @@ -13837,7 +13836,7 @@ index_copy_data(Relation rel, RelFileNode newrnode) (rel->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED && forkNum == INIT_FORKNUM)) log_smgrcreate(&newrnode, forkNum); - RelationCopyStorage(rel->rd_smgr, dstrel, forkNum, + RelationCopyStorage(RelationGetSmgr(rel), dstrel, forkNum, rel->rd_rel->relpersistence); } } diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c index b32184591f6..69a14016547 100644 --- a/src/backend/storage/buffer/bufmgr.c +++ b/src/backend/storage/buffer/bufmgr.c @@ -576,9 +576,6 @@ PrefetchBuffer(Relation reln, ForkNumber forkNum, BlockNumber blockNum) Assert(RelationIsValid(reln)); Assert(BlockNumberIsValid(blockNum)); - /* Open it at the smgr level if not already done */ - RelationOpenSmgr(reln); - if (RelationUsesLocalBuffers(reln)) { /* see comments in ReadBufferExtended */ @@ -588,12 +585,12 @@ PrefetchBuffer(Relation reln, ForkNumber forkNum, BlockNumber blockNum) errmsg("cannot access temporary tables of other sessions"))); /* pass it off to localbuf.c */ - return PrefetchLocalBuffer(reln->rd_smgr, forkNum, blockNum); + return PrefetchLocalBuffer(RelationGetSmgr(reln), forkNum, blockNum); } else { /* pass it to the shared buffer version */ - return PrefetchSharedBuffer(reln->rd_smgr, forkNum, blockNum); + return PrefetchSharedBuffer(RelationGetSmgr(reln), forkNum, blockNum); } } @@ -656,9 +653,6 @@ ReadBufferExtended(Relation reln, ForkNumber forkNum, BlockNumber blockNum, bool hit; Buffer buf; - /* Open it at the smgr level if not already done */ - RelationOpenSmgr(reln); - /* * Reject attempts to read non-local temporary relations; we would be * likely to get wrong data since we have no visibility into the owning @@ -674,7 +668,7 @@ ReadBufferExtended(Relation reln, ForkNumber forkNum, BlockNumber blockNum, * miss. */ pgstat_count_buffer_read(reln); - buf = ReadBuffer_common(reln->rd_smgr, reln->rd_rel->relpersistence, + buf = ReadBuffer_common(RelationGetSmgr(reln), reln->rd_rel->relpersistence, forkNum, blockNum, mode, strategy, &hit); if (hit) pgstat_count_buffer_hit(reln); @@ -2835,10 +2829,7 @@ RelationGetNumberOfBlocksInFork(Relation relation, ForkNumber forkNum) case RELKIND_SEQUENCE: case RELKIND_INDEX: case RELKIND_PARTITIONED_INDEX: - /* Open it at the smgr level if not already done */ - RelationOpenSmgr(relation); - - return smgrnblocks(relation->rd_smgr, forkNum); + return smgrnblocks(RelationGetSmgr(relation), forkNum); case RELKIND_RELATION: case RELKIND_TOASTVALUE: @@ -3237,9 +3228,6 @@ FlushRelationBuffers(Relation rel) int i; BufferDesc *bufHdr; - /* Open rel at the smgr level if not already done */ - RelationOpenSmgr(rel); - if (RelationUsesLocalBuffers(rel)) { for (i = 0; i < NLocBuffer; i++) @@ -3264,7 +3252,7 @@ FlushRelationBuffers(Relation rel) PageSetChecksumInplace(localpage, bufHdr->tag.blockNum); - smgrwrite(rel->rd_smgr, + smgrwrite(RelationGetSmgr(rel), bufHdr->tag.forkNum, bufHdr->tag.blockNum, localpage, @@ -3305,7 +3293,7 @@ FlushRelationBuffers(Relation rel) { PinBuffer_Locked(bufHdr); LWLockAcquire(BufferDescriptorGetContentLock(bufHdr), LW_SHARED); - FlushBuffer(bufHdr, rel->rd_smgr); + FlushBuffer(bufHdr, RelationGetSmgr(rel)); LWLockRelease(BufferDescriptorGetContentLock(bufHdr)); UnpinBuffer(bufHdr, true); } diff --git a/src/backend/storage/freespace/freespace.c b/src/backend/storage/freespace/freespace.c index 95a21f6cc38..72cce7a84f2 100644 --- a/src/backend/storage/freespace/freespace.c +++ b/src/backend/storage/freespace/freespace.c @@ -265,13 +265,11 @@ FreeSpaceMapPrepareTruncateRel(Relation rel, BlockNumber nblocks) uint16 first_removed_slot; Buffer buf; - RelationOpenSmgr(rel); - /* * If no FSM has been created yet for this relation, there's nothing to * truncate. */ - if (!smgrexists(rel->rd_smgr, FSM_FORKNUM)) + if (!smgrexists(RelationGetSmgr(rel), FSM_FORKNUM)) return InvalidBlockNumber; /* Get the location in the FSM of the first removed heap block */ @@ -317,7 +315,7 @@ FreeSpaceMapPrepareTruncateRel(Relation rel, BlockNumber nblocks) else { new_nfsmblocks = fsm_logical_to_physical(first_removed_address); - if (smgrnblocks(rel->rd_smgr, FSM_FORKNUM) <= new_nfsmblocks) + if (smgrnblocks(RelationGetSmgr(rel), FSM_FORKNUM) <= new_nfsmblocks) return InvalidBlockNumber; /* nothing to do; the FSM was already * smaller */ } @@ -532,8 +530,14 @@ fsm_readbuf(Relation rel, FSMAddress addr, bool extend) { BlockNumber blkno = fsm_logical_to_physical(addr); Buffer buf; + SMgrRelation reln; - RelationOpenSmgr(rel); + /* + * Caution: re-using this smgr pointer could fail if the relcache entry + * gets closed. It's safe as long as we only do smgr-level operations + * between here and the last use of the pointer. + */ + reln = RelationGetSmgr(rel); /* * If we haven't cached the size of the FSM yet, check it first. Also @@ -541,18 +545,18 @@ fsm_readbuf(Relation rel, FSMAddress addr, bool extend) * value might be stale. (We send smgr inval messages on truncation, but * not on extension.) */ - if (rel->rd_smgr->smgr_fsm_nblocks == InvalidBlockNumber || - blkno >= rel->rd_smgr->smgr_fsm_nblocks) + if (reln->smgr_fsm_nblocks == InvalidBlockNumber || + blkno >= reln->smgr_fsm_nblocks) { - if (smgrexists(rel->rd_smgr, FSM_FORKNUM)) - rel->rd_smgr->smgr_fsm_nblocks = smgrnblocks(rel->rd_smgr, - FSM_FORKNUM); + if (smgrexists(reln, FSM_FORKNUM)) + reln->smgr_fsm_nblocks = smgrnblocks(reln, + FSM_FORKNUM); else - rel->rd_smgr->smgr_fsm_nblocks = 0; + reln->smgr_fsm_nblocks = 0; } /* Handle requests beyond EOF */ - if (blkno >= rel->rd_smgr->smgr_fsm_nblocks) + if (blkno >= reln->smgr_fsm_nblocks) { if (extend) fsm_extend(rel, blkno + 1); @@ -602,6 +606,7 @@ fsm_extend(Relation rel, BlockNumber fsm_nblocks) { BlockNumber fsm_nblocks_now; PGAlignedBlock pg; + SMgrRelation reln; PageInit((Page) pg.data, BLCKSZ, 0); @@ -617,31 +622,35 @@ fsm_extend(Relation rel, BlockNumber fsm_nblocks) */ LockRelationForExtension(rel, ExclusiveLock); - /* Might have to re-open if a cache flush happened */ - RelationOpenSmgr(rel); + /* + * Caution: re-using this smgr pointer could fail if the relcache entry + * gets closed. It's safe as long as we only do smgr-level operations + * between here and the last use of the pointer. + */ + reln = RelationGetSmgr(rel); /* * Create the FSM file first if it doesn't exist. If smgr_fsm_nblocks is * positive then it must exist, no need for an smgrexists call. */ - if ((rel->rd_smgr->smgr_fsm_nblocks == 0 || - rel->rd_smgr->smgr_fsm_nblocks == InvalidBlockNumber) && - !smgrexists(rel->rd_smgr, FSM_FORKNUM)) - smgrcreate(rel->rd_smgr, FSM_FORKNUM, false); + if ((reln->smgr_fsm_nblocks == 0 || + reln->smgr_fsm_nblocks == InvalidBlockNumber) && + !smgrexists(reln, FSM_FORKNUM)) + smgrcreate(reln, FSM_FORKNUM, false); - fsm_nblocks_now = smgrnblocks(rel->rd_smgr, FSM_FORKNUM); + fsm_nblocks_now = smgrnblocks(reln, FSM_FORKNUM); while (fsm_nblocks_now < fsm_nblocks) { PageSetChecksumInplace((Page) pg.data, fsm_nblocks_now); - smgrextend(rel->rd_smgr, FSM_FORKNUM, fsm_nblocks_now, + smgrextend(reln, FSM_FORKNUM, fsm_nblocks_now, pg.data, false); fsm_nblocks_now++; } /* Update local cache with the up-to-date size */ - rel->rd_smgr->smgr_fsm_nblocks = fsm_nblocks_now; + reln->smgr_fsm_nblocks = fsm_nblocks_now; UnlockRelationForExtension(rel, ExclusiveLock); } diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h index b7c10864eb5..8d9f7006c3d 100644 --- a/src/include/utils/rel.h +++ b/src/include/utils/rel.h @@ -24,6 +24,7 @@ #include "rewrite/prs2lock.h" #include "storage/block.h" #include "storage/relfilenode.h" +#include "storage/smgr.h" #include "utils/relcache.h" #include "utils/reltrigger.h" @@ -53,8 +54,7 @@ typedef LockInfoData *LockInfo; typedef struct RelationData { RelFileNode rd_node; /* relation physical identifier */ - /* use "struct" here to avoid needing to include smgr.h: */ - struct SMgrRelationData *rd_smgr; /* cached file handle, or NULL */ + SMgrRelation rd_smgr; /* cached file handle, or NULL */ int rd_refcnt; /* reference count */ BackendId rd_backend; /* owning backend id, if temporary relation */ bool rd_islocaltemp; /* rel is a temp rel of this session */ @@ -505,9 +505,33 @@ typedef struct ViewOptions (RELKIND_HAS_STORAGE((relation)->rd_rel->relkind) && \ ((relation)->rd_rel->relfilenode == InvalidOid)) +/* + * RelationGetSmgr + * Returns smgr file handle for a relation, opening it if needed. + * + * Very little code is authorized to touch rel->rd_smgr directly. Instead + * use this function to fetch its value. + * + * Note: since a relcache flush can cause the file handle to be closed again, + * it's unwise to hold onto the pointer returned by this function for any + * long period. Recommended practice is to just re-execute RelationGetSmgr + * each time you need to access the SMgrRelation. It's quite cheap in + * comparison to whatever an smgr function is going to do. + */ +static inline SMgrRelation +RelationGetSmgr(Relation rel) +{ + if (unlikely(rel->rd_smgr == NULL)) + smgrsetowner(&(rel->rd_smgr), smgropen(rel->rd_node, rel->rd_backend)); + return rel->rd_smgr; +} + /* * RelationOpenSmgr * Open the relation at the smgr level, if not already done. + * + * XXX this is now deprecated, and should not be used in new code. + * Instead, call RelationGetSmgr in place of fetching rd_smgr directly. */ #define RelationOpenSmgr(relation) \ do { \ @@ -535,7 +559,8 @@ typedef struct ViewOptions * Fetch relation's current insertion target block. * * Returns InvalidBlockNumber if there is no current target block. Note - * that the target block status is discarded on any smgr-level invalidation. + * that the target block status is discarded on any smgr-level invalidation, + * so there's no need to re-open the smgr handle if it's not currently open. */ #define RelationGetTargetBlock(relation) \ ( (relation)->rd_smgr != NULL ? (relation)->rd_smgr->smgr_targblock : InvalidBlockNumber ) @@ -546,8 +571,7 @@ typedef struct ViewOptions */ #define RelationSetTargetBlock(relation, targblock) \ do { \ - RelationOpenSmgr(relation); \ - (relation)->rd_smgr->smgr_targblock = (targblock); \ + RelationGetSmgr(relation)->smgr_targblock = (targblock); \ } while (0) /*