From d4acf2eb94f3464d5f439ca83a4188496cd5841a Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 17 Nov 2022 16:54:31 -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 | 4 +- src/backend/access/gist/gistbuild.c | 2 +- src/backend/access/hash/hashpage.c | 4 +- src/backend/access/heap/heapam.c | 5 +- src/backend/access/heap/rewriteheap.c | 7 +-- src/backend/access/heap/visibilitymap.c | 56 ++++++++++++----------- src/backend/access/nbtree/nbtree.c | 6 +-- src/backend/access/nbtree/nbtsort.c | 14 ++---- src/backend/access/spgist/spginsert.c | 14 +++--- src/backend/catalog/heap.c | 10 ++-- src/backend/catalog/index.c | 5 +- src/backend/catalog/storage.c | 20 ++++---- src/backend/commands/tablecmds.c | 8 ++-- src/backend/storage/buffer/bufmgr.c | 26 +++-------- src/backend/storage/freespace/freespace.c | 53 ++++++++++++--------- src/include/utils/rel.h | 34 ++++++++++++-- 20 files changed, 144 insertions(+), 142 deletions(-) diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c index 4c4ca02891f..5b75c891efc 100644 --- a/contrib/amcheck/verify_nbtree.c +++ b/contrib/amcheck/verify_nbtree.c @@ -278,8 +278,7 @@ bt_index_check_internal(Oid indrelid, bool parentcheck, bool heapallindexed) if (btree_index_mainfork_expected(indrel)) { - 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 9f223d3b2a7..cd85703c1be 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 33b907f13bb..5b2a6e2d3ac 100644 --- a/contrib/pg_prewarm/autoprewarm.c +++ b/contrib/pg_prewarm/autoprewarm.c @@ -522,15 +522,13 @@ 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 1f4bfb8c0d4..c89d3b1390d 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 944dea66fc8..8009bb381cc 100644 --- a/contrib/pg_visibility/pg_visibility.c +++ b/contrib/pg_visibility/pg_visibility.c @@ -387,8 +387,8 @@ 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; visibilitymap_truncate(rel, 0); diff --git a/src/backend/access/gist/gistbuild.c b/src/backend/access/gist/gistbuild.c index b9c4e27e1a5..e84bc2e4c15 100644 --- a/src/backend/access/gist/gistbuild.c +++ b/src/backend/access/gist/gistbuild.c @@ -513,7 +513,7 @@ 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 1d2d3c01344..f698c5fc058 100644 --- a/src/backend/access/hash/hashpage.c +++ b/src/backend/access/hash/hashpage.c @@ -1041,9 +1041,9 @@ _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.c b/src/backend/access/heap/heapam.c index f17d434c9d5..848062375e7 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -9538,8 +9538,7 @@ heap_sync(Relation rel) /* main heap */ FlushRelationBuffers(rel); - /* FlushRelationBuffers will have opened rd_smgr */ - smgrimmedsync(rel->rd_smgr, MAIN_FORKNUM); + smgrimmedsync(RelationGetSmgr(rel), MAIN_FORKNUM); /* FSM is not critical, don't bother syncing it */ @@ -9550,7 +9549,7 @@ heap_sync(Relation rel) toastrel = heap_open(rel->rd_rel->reltoastrelid, AccessShareLock); FlushRelationBuffers(toastrel); - smgrimmedsync(toastrel->rd_smgr, MAIN_FORKNUM); + smgrimmedsync(RelationGetSmgr(toastrel), MAIN_FORKNUM); heap_close(toastrel, AccessShareLock); } } diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c index b4092bb7325..b5b9c189b71 100644 --- a/src/backend/access/heap/rewriteheap.c +++ b/src/backend/access/heap/rewriteheap.c @@ -337,11 +337,10 @@ end_heap_rewrite(RewriteState state) state->rs_blockno, state->rs_buffer, true); - RelationOpenSmgr(state->rs_new_rel); PageSetChecksumInplace(state->rs_buffer, state->rs_blockno); - smgrextend(state->rs_new_rel->rd_smgr, MAIN_FORKNUM, state->rs_blockno, + smgrextend(RelationGetSmgr(state->rs_new_rel), MAIN_FORKNUM, state->rs_blockno, (char *) state->rs_buffer, true); } @@ -709,11 +708,9 @@ raw_heap_insert(RewriteState state, HeapTuple tup) * 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 695567b4b0d..62bb9e971d5 100644 --- a/src/backend/access/heap/visibilitymap.c +++ b/src/backend/access/heap/visibilitymap.c @@ -472,13 +472,11 @@ visibilitymap_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; /* @@ -545,14 +543,14 @@ visibilitymap_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; } /* Truncate the unused VM pages, and send smgr inval message */ - smgrtruncate(rel->rd_smgr, VISIBILITYMAP_FORKNUM, newnblocks); + smgrtruncate(RelationGetSmgr(rel), VISIBILITYMAP_FORKNUM, newnblocks); /* * We might as well update the local smgr_vm_nblocks setting. smgrtruncate @@ -574,31 +572,30 @@ 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); @@ -646,6 +643,7 @@ vm_extend(Relation rel, BlockNumber vm_nblocks) { BlockNumber vm_nblocks_now; PGAlignedBlock pg; + SMgrRelation reln; PageInit((Page) pg.data, BLCKSZ, 0); @@ -661,26 +659,30 @@ 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++; } @@ -692,10 +694,10 @@ 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 fcb36ebcc05..18b370376db 100644 --- a/src/backend/access/nbtree/nbtree.c +++ b/src/backend/access/nbtree/nbtree.c @@ -168,9 +168,9 @@ 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); /* @@ -178,7 +178,7 @@ 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 9025c5c8c67..038aefe745a 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -610,9 +610,6 @@ _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) { @@ -632,7 +629,7 @@ _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); @@ -647,14 +644,14 @@ _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); } @@ -1208,10 +1205,7 @@ _bt_load(BTWriteState *wstate, BTSpool *btspool, BTSpool *btspool2) * occurs. */ if (RelationNeedsWAL(wstate->index)) - { - 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 7dd0d61fbbc..4b0103b2937 100644 --- a/src/backend/access/spgist/spginsert.c +++ b/src/backend/access/spgist/spginsert.c @@ -177,27 +177,27 @@ 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); /* @@ -205,7 +205,7 @@ 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/catalog/heap.c b/src/backend/catalog/heap.c index 6a5a0819929..846c530154a 100644 --- a/src/backend/catalog/heap.c +++ b/src/backend/catalog/heap.c @@ -371,10 +371,7 @@ heap_create(const char *relname, * demand. */ if (create_storage) - { - RelationOpenSmgr(rel); RelationCreateStorage(rel->rd_node, relpersistence); - } /* * If a tablespace is specified, removal of that tablespace is normally @@ -1411,10 +1408,9 @@ heap_create_init_fork(Relation rel) Assert(rel->rd_rel->relkind == RELKIND_RELATION || rel->rd_rel->relkind == RELKIND_MATVIEW || rel->rd_rel->relkind == RELKIND_TOASTVALUE); - RelationOpenSmgr(rel); - smgrcreate(rel->rd_smgr, INIT_FORKNUM, false); - log_smgrcreate(&rel->rd_smgr->smgr_rnode.node, INIT_FORKNUM); - smgrimmedsync(rel->rd_smgr, INIT_FORKNUM); + smgrcreate(RelationGetSmgr(rel), INIT_FORKNUM, false); + log_smgrcreate(&(RelationGetSmgr(rel)->smgr_rnode.node), INIT_FORKNUM); + smgrimmedsync(RelationGetSmgr(rel), INIT_FORKNUM); } /* diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c index 234bf7f8548..6c71d41d65b 100644 --- a/src/backend/catalog/index.c +++ b/src/backend/catalog/index.c @@ -2424,10 +2424,9 @@ 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_amroutine->ambuildempty(indexRelation); } diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c index 76a75a46b82..65962148dd6 100644 --- a/src/backend/catalog/storage.c +++ b/src/backend/catalog/storage.c @@ -228,24 +228,24 @@ RelationTruncate(Relation rel, BlockNumber nblocks) { bool fsm; bool vm; - - /* 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; /* Truncate the FSM first if it exists */ - fsm = smgrexists(rel->rd_smgr, FSM_FORKNUM); + fsm = smgrexists(reln, FSM_FORKNUM); if (fsm) FreeSpaceMapTruncateRel(rel, nblocks); /* Truncate the visibility map too if it exists. */ - vm = smgrexists(rel->rd_smgr, VISIBILITYMAP_FORKNUM); + vm = smgrexists(RelationGetSmgr(rel), VISIBILITYMAP_FORKNUM); if (vm) visibilitymap_truncate(rel, nblocks); @@ -308,7 +308,7 @@ RelationTruncate(Relation rel, BlockNumber nblocks) * longer exist after truncation is complete, and then truncate the * corresponding files on disk. */ - smgrtruncate(rel->rd_smgr, MAIN_FORKNUM, nblocks); + smgrtruncate(RelationGetSmgr(rel), MAIN_FORKNUM, nblocks); /* We've done all the critical work, so checkpoints are OK now. */ MyProc->delayChkptEnd = false; diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 14faa61380a..f56219973e1 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -11955,8 +11955,6 @@ ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode) newrnode.spcNode = newTableSpace; dstrel = smgropen(newrnode, rel->rd_backend); - RelationOpenSmgr(rel); - /* * Create and copy all forks of the relation, and schedule unlinking of * old physical files. @@ -11967,13 +11965,13 @@ ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode) RelationCreateStorage(newrnode, rel->rd_rel->relpersistence); /* copy main fork */ - copy_relation_data(rel->rd_smgr, dstrel, MAIN_FORKNUM, + copy_relation_data(RelationGetSmgr(rel), dstrel, MAIN_FORKNUM, rel->rd_rel->relpersistence); /* copy those extra forks that exist */ for (forkNum = MAIN_FORKNUM + 1; forkNum <= MAX_FORKNUM; forkNum++) { - if (smgrexists(rel->rd_smgr, forkNum)) + if (smgrexists(RelationGetSmgr(rel), forkNum)) { smgrcreate(dstrel, forkNum, false); @@ -11985,7 +11983,7 @@ ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode) (rel->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED && forkNum == INIT_FORKNUM)) log_smgrcreate(&newrnode, forkNum); - copy_relation_data(rel->rd_smgr, dstrel, forkNum, + copy_relation_data(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 f0f3f02b2e2..5ea6bd6221d 100644 --- a/src/backend/storage/buffer/bufmgr.c +++ b/src/backend/storage/buffer/bufmgr.c @@ -532,9 +532,6 @@ 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 */ @@ -544,7 +541,7 @@ PrefetchBuffer(Relation reln, ForkNumber forkNum, BlockNumber blockNum) errmsg("cannot access temporary tables of other sessions"))); /* pass it off to localbuf.c */ - LocalPrefetchBuffer(reln->rd_smgr, forkNum, blockNum); + LocalPrefetchBuffer(RelationGetSmgr(reln), forkNum, blockNum); } else { @@ -554,7 +551,7 @@ PrefetchBuffer(Relation reln, ForkNumber forkNum, BlockNumber blockNum) int buf_id; /* create a tag so we can lookup the buffer */ - INIT_BUFFERTAG(newTag, reln->rd_smgr->smgr_rnode.node, + INIT_BUFFERTAG(newTag, RelationGetSmgr(reln)->smgr_rnode.node, forkNum, blockNum); /* determine its hash code and partition lock ID */ @@ -568,7 +565,7 @@ PrefetchBuffer(Relation reln, ForkNumber forkNum, BlockNumber blockNum) /* If not in buffers, initiate prefetch */ if (buf_id < 0) - smgrprefetch(reln->rd_smgr, forkNum, blockNum); + smgrprefetch(RelationGetSmgr(reln), forkNum, blockNum); /* * If the block *is* in buffers, we do nothing. This is not really @@ -644,9 +641,6 @@ 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 @@ -662,7 +656,7 @@ 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); @@ -2798,10 +2792,7 @@ FlushBuffer(BufferDesc *buf, SMgrRelation reln) BlockNumber RelationGetNumberOfBlocksInFork(Relation relation, ForkNumber forkNum) { - /* Open it at the smgr level if not already done */ - RelationOpenSmgr(relation); - - return smgrnblocks(relation->rd_smgr, forkNum); + return smgrnblocks(RelationGetSmgr(relation), forkNum); } /* @@ -3161,9 +3152,6 @@ 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++) @@ -3188,7 +3176,7 @@ FlushRelationBuffers(Relation rel) PageSetChecksumInplace(localpage, bufHdr->tag.blockNum); - smgrwrite(rel->rd_smgr, + smgrwrite(RelationGetSmgr(rel), bufHdr->tag.forkNum, bufHdr->tag.blockNum, localpage, @@ -3229,7 +3217,7 @@ 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 7c4ad1c4494..e4d84ca38c4 100644 --- a/src/backend/storage/freespace/freespace.c +++ b/src/backend/storage/freespace/freespace.c @@ -263,13 +263,11 @@ FreeSpaceMapTruncateRel(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; /* Get the location in the FSM of the first removed heap block */ @@ -314,12 +312,12 @@ FreeSpaceMapTruncateRel(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; /* nothing to do; the FSM was already smaller */ } /* Truncate the unused FSM pages, and send smgr inval message */ - smgrtruncate(rel->rd_smgr, FSM_FORKNUM, new_nfsmblocks); + smgrtruncate(RelationGetSmgr(rel), FSM_FORKNUM, new_nfsmblocks); /* * We might as well update the local smgr_fsm_nblocks setting. @@ -546,8 +544,14 @@ 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 @@ -555,18 +559,18 @@ 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); @@ -616,6 +620,7 @@ fsm_extend(Relation rel, BlockNumber fsm_nblocks) { BlockNumber fsm_nblocks_now; PGAlignedBlock pg; + SMgrRelation reln; PageInit((Page) pg.data, BLCKSZ, 0); @@ -631,31 +636,35 @@ 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 11a635964fd..40cc47ad254 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 */ @@ -468,9 +468,33 @@ typedef struct ViewOptions #define RelationIsMapped(relation) \ ((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 { \ @@ -498,7 +522,8 @@ 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 ) @@ -509,8 +534,7 @@ typedef struct ViewOptions */ #define RelationSetTargetBlock(relation, targblock) \ do { \ - RelationOpenSmgr(relation); \ - (relation)->rd_smgr->smgr_targblock = (targblock); \ + RelationGetSmgr(relation)->smgr_targblock = (targblock); \ } while (0) /*