From 4c6780fd17aa43ed6362aa682499cc2f9712cc8b Mon Sep 17 00:00:00 2001 From: Bruce Momjian Date: Thu, 7 Aug 2014 14:56:13 -0400 Subject: [PATCH] pg_upgrade: prevent oid conflicts with new-cluster TOAST tables Previously, TOAST tables only required in the new cluster could cause oid conflicts if they were auto-numbered and a later conflicting oid had to be assigned. Backpatch through 9.3 --- contrib/pg_upgrade/dump.c | 70 ++++++++++++++++++++++++++++ contrib/pg_upgrade/pg_upgrade.c | 2 + contrib/pg_upgrade/pg_upgrade.h | 1 + src/backend/catalog/toasting.c | 55 ++++++++++++++++++---- src/include/catalog/binary_upgrade.h | 5 ++ 5 files changed, 123 insertions(+), 10 deletions(-) diff --git a/contrib/pg_upgrade/dump.c b/contrib/pg_upgrade/dump.c index b112f3a952..e623a22632 100644 --- a/contrib/pg_upgrade/dump.c +++ b/contrib/pg_upgrade/dump.c @@ -12,6 +12,8 @@ #include "pg_upgrade.h" #include +#include "catalog/binary_upgrade.h" + void generate_old_dump(void) @@ -67,3 +69,71 @@ generate_old_dump(void) end_progress_output(); check_ok(); } + + +/* + * It is possible for there to be a mismatch in the need for TOAST tables + * between the old and new servers, e.g. some pre-9.1 tables didn't need + * TOAST tables but will need them in 9.1+. (There are also opposite cases, + * but these are handled by setting binary_upgrade_next_toast_pg_class_oid.) + * + * We can't allow the TOAST table to be created by pg_dump with a + * pg_dump-assigned oid because it might conflict with a later table that + * uses that oid, causing a "file exists" error for pg_class conflicts, and + * a "duplicate oid" error for pg_type conflicts. (TOAST tables need pg_type + * entries.) + * + * Therefore, a backend in binary-upgrade mode will not create a TOAST + * table unless an OID as passed in via pg_upgrade_support functions. + * This function is called after the restore and uses ALTER TABLE to + * auto-create any needed TOAST tables which will not conflict with + * restored oids. + */ +void +optionally_create_toast_tables(void) +{ + int dbnum; + + prep_status("Creating newly-required TOAST tables"); + + for (dbnum = 0; dbnum < new_cluster.dbarr.ndbs; dbnum++) + { + PGresult *res; + int ntups; + int rowno; + int i_nspname, + i_relname; + DbInfo *active_db = &new_cluster.dbarr.dbs[dbnum]; + PGconn *conn = connectToServer(&new_cluster, active_db->db_name); + + res = executeQueryOrDie(conn, + "SELECT n.nspname, c.relname " + "FROM pg_catalog.pg_class c, " + " pg_catalog.pg_namespace n " + "WHERE c.relnamespace = n.oid AND " + " n.nspname NOT IN ('pg_catalog', 'information_schema') AND " + "c.relkind IN ('r', 'm') AND " + "c.reltoastrelid = 0"); + + ntups = PQntuples(res); + i_nspname = PQfnumber(res, "nspname"); + i_relname = PQfnumber(res, "relname"); + for (rowno = 0; rowno < ntups; rowno++) + { + /* enable auto-oid-numbered TOAST creation if needed */ + PQclear(executeQueryOrDie(conn, "SELECT binary_upgrade.set_next_toast_pg_class_oid('%d'::pg_catalog.oid);", + OPTIONALLY_CREATE_TOAST_OID)); + + /* dummy command that also triggers check for required TOAST table */ + PQclear(executeQueryOrDie(conn, "ALTER TABLE %s.%s RESET (binary_upgrade_dummy_option);", + quote_identifier(PQgetvalue(res, rowno, i_nspname)), + quote_identifier(PQgetvalue(res, rowno, i_relname)))); + } + + PQclear(res); + + PQfinish(conn); + } + + check_ok(); +} diff --git a/contrib/pg_upgrade/pg_upgrade.c b/contrib/pg_upgrade/pg_upgrade.c index 3e97b66476..49ea873099 100644 --- a/contrib/pg_upgrade/pg_upgrade.c +++ b/contrib/pg_upgrade/pg_upgrade.c @@ -363,6 +363,8 @@ create_new_objects(void) if (GET_MAJOR_VERSION(old_cluster.major_version) < 903) set_frozenxids(true); + optionally_create_toast_tables(); + /* regenerate now that we have objects in the databases */ get_db_and_rel_infos(&new_cluster); diff --git a/contrib/pg_upgrade/pg_upgrade.h b/contrib/pg_upgrade/pg_upgrade.h index 61e5de015c..1175604e37 100644 --- a/contrib/pg_upgrade/pg_upgrade.h +++ b/contrib/pg_upgrade/pg_upgrade.h @@ -336,6 +336,7 @@ void disable_old_cluster(void); /* dump.c */ void generate_old_dump(void); +void optionally_create_toast_tables(void); /* exec.c */ diff --git a/src/backend/catalog/toasting.c b/src/backend/catalog/toasting.c index bdfeb90dd1..94543e1d51 100644 --- a/src/backend/catalog/toasting.c +++ b/src/backend/catalog/toasting.c @@ -165,16 +165,51 @@ create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid, if (rel->rd_rel->reltoastrelid != InvalidOid) return false; - /* - * Check to see whether the table actually needs a TOAST table. - * - * If an update-in-place toast relfilenode is specified, force toast file - * creation even if it seems not to need one. - */ - if (!needs_toast_table(rel) && - (!IsBinaryUpgrade || - !OidIsValid(binary_upgrade_next_toast_pg_class_oid))) - return false; + if (!IsBinaryUpgrade) + { + if (!needs_toast_table(rel)) + return false; + } + else + { + /* + * Check to see whether the table needs a TOAST table. + * + * If an update-in-place TOAST relfilenode is specified, force TOAST file + * creation even if it seems not to need one. This handles the case + * where the old cluster needed a TOAST table but the new cluster + * would not normally create one. + */ + + /* + * If a TOAST oid is not specified, skip TOAST creation as we will do + * it later so we don't create a TOAST table whose OID later conflicts + * with a user-supplied OID. This handles cases where the old cluster + * didn't need a TOAST table, but the new cluster does. + */ + if (!OidIsValid(binary_upgrade_next_toast_pg_class_oid)) + return false; + + /* + * If a special TOAST value has been passed in, it means we are in + * cleanup mode --- we are creating needed TOAST tables after all user + * tables with specified OIDs have been created. We let the system + * assign a TOAST oid for us. The tables are empty so the missing + * TOAST tables were not a problem. + */ + if (binary_upgrade_next_toast_pg_class_oid == OPTIONALLY_CREATE_TOAST_OID) + { + /* clear as it is not to be used; it is just a flag */ + binary_upgrade_next_toast_pg_class_oid = InvalidOid; + + if (!needs_toast_table(rel)) + return false; + } + + /* both should be set, or not set */ + Assert(OidIsValid(binary_upgrade_next_toast_pg_class_oid) == + OidIsValid(binary_upgrade_next_toast_pg_type_oid)); + } /* * If requested check lockmode is sufficient. This is a cross check in diff --git a/src/include/catalog/binary_upgrade.h b/src/include/catalog/binary_upgrade.h index f39017cfdf..63fa85ed99 100644 --- a/src/include/catalog/binary_upgrade.h +++ b/src/include/catalog/binary_upgrade.h @@ -14,6 +14,11 @@ #ifndef BINARY_UPGRADE_H #define BINARY_UPGRADE_H +#include "catalog/pg_authid.h" + +/* pick a OID that will never be used for TOAST tables */ +#define OPTIONALLY_CREATE_TOAST_OID BOOTSTRAP_SUPERUSERID + extern PGDLLIMPORT Oid binary_upgrade_next_pg_type_oid; extern PGDLLIMPORT Oid binary_upgrade_next_array_pg_type_oid; extern PGDLLIMPORT Oid binary_upgrade_next_toast_pg_type_oid; -- 2.40.0