From 6a05a305f3e4c4e5b9bb368f3e18d502e779a3b8 Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Fri, 10 Dec 2021 11:45:24 +1300 Subject: [PATCH v10 1/6] Allow "in place" tablespaces. Provide a developer-only GUC allow_in_place_tablespaces, disabled by default. When enabled, tablespaces can be created with an empty LOCATION string, meaning that they should be created as a directory directly beneath pg_tblspc. This can be used for new testing scenarios, in a follow-up patch. Not intended for end-user usage, since it might confuse backup tools that expect symlinks. Reviewed-by: Andres Freund Reviewed-by: Michael Paquier Discussion: https://postgr.es/m/CA%2BhUKGKpRWQ9SxdxxDmTBCJoR0YnFpMBe7kyzY8SUQk%2BHeskxg%40mail.gmail.com --- src/backend/commands/tablespace.c | 39 +++++++++++++++++++++++++------ src/backend/utils/misc/guc.c | 12 ++++++++++ src/include/commands/tablespace.h | 2 ++ 3 files changed, 46 insertions(+), 7 deletions(-) diff --git a/src/backend/commands/tablespace.c b/src/backend/commands/tablespace.c index 4b96eec9df..c198501cbf 100644 --- a/src/backend/commands/tablespace.c +++ b/src/backend/commands/tablespace.c @@ -87,6 +87,7 @@ /* GUC variables */ char *default_tablespace = NULL; char *temp_tablespaces = NULL; +bool allow_in_place_tablespaces = false; static void create_tablespace_directories(const char *location, @@ -241,6 +242,7 @@ CreateTableSpace(CreateTableSpaceStmt *stmt) char *location; Oid ownerId; Datum newOptions; + bool in_place; /* Must be superuser */ if (!superuser()) @@ -266,12 +268,15 @@ CreateTableSpace(CreateTableSpaceStmt *stmt) (errcode(ERRCODE_INVALID_NAME), errmsg("tablespace location cannot contain single quotes"))); + in_place = allow_in_place_tablespaces && strlen(location) == 0; + /* * Allowing relative paths seems risky * - * this also helps us ensure that location is not empty or whitespace + * This also helps us ensure that location is not empty or whitespace, + * unless specifying a developer-only in-place tablespace. */ - if (!is_absolute_path(location)) + if (!in_place && !is_absolute_path(location)) ereport(ERROR, (errcode(ERRCODE_INVALID_OBJECT_DEFINITION), errmsg("tablespace location must be an absolute path"))); @@ -590,16 +595,36 @@ create_tablespace_directories(const char *location, const Oid tablespaceoid) char *linkloc; char *location_with_version_dir; struct stat st; + bool in_place; linkloc = psprintf("pg_tblspc/%u", tablespaceoid); - location_with_version_dir = psprintf("%s/%s", location, + + /* + * If we're asked to make an 'in place' tablespace, create the directory + * directly where the symlink would normally go. This is a developer-only + * option for now, to facilitate regression testing. + */ + in_place = strlen(location) == 0; + + if (in_place) + { + if (MakePGDirectory(linkloc) < 0 && errno != EEXIST) + ereport(ERROR, + (errcode_for_file_access(), + errmsg("could not create directory \"%s\": %m", + linkloc))); + } + + location_with_version_dir = psprintf("%s/%s", in_place ? linkloc : location, TABLESPACE_VERSION_DIRECTORY); /* * Attempt to coerce target directory to safe permissions. If this fails, - * it doesn't exist or has the wrong owner. + * it doesn't exist or has the wrong owner. Not needed for in-place mode, + * because in that case we created the directory with the desired + * permissions. */ - if (chmod(location, pg_dir_create_mode) != 0) + if (!in_place && chmod(location, pg_dir_create_mode) != 0) { if (errno == ENOENT) ereport(ERROR, @@ -648,13 +673,13 @@ create_tablespace_directories(const char *location, const Oid tablespaceoid) /* * In recovery, remove old symlink, in case it points to the wrong place. */ - if (InRecovery) + if (!in_place && InRecovery) remove_tablespace_symlink(linkloc); /* * Create the symlink under PGDATA */ - if (symlink(location, linkloc) < 0) + if (!in_place && symlink(location, linkloc) < 0) ereport(ERROR, (errcode_for_file_access(), errmsg("could not create symbolic link \"%s\": %m", diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c index bff949a40b..ea655bd98e 100644 --- a/src/backend/utils/misc/guc.c +++ b/src/backend/utils/misc/guc.c @@ -46,6 +46,7 @@ #include "catalog/storage.h" #include "commands/async.h" #include "commands/prepare.h" +#include "commands/tablespace.h" #include "commands/trigger.h" #include "commands/user.h" #include "commands/vacuum.h" @@ -1963,6 +1964,17 @@ static struct config_bool ConfigureNamesBool[] = NULL, NULL, NULL }, + { + {"allow_in_place_tablespaces", PGC_SUSET, DEVELOPER_OPTIONS, + gettext_noop("Allows tablespaces directly inside pg_tblspc, for testing."), + NULL, + GUC_NOT_IN_SAMPLE + }, + &allow_in_place_tablespaces, + false, + NULL, NULL, NULL + }, + { {"lo_compat_privileges", PGC_SUSET, COMPAT_OPTIONS_PREVIOUS, gettext_noop("Enables backward compatibility mode for privilege checks on large objects."), diff --git a/src/include/commands/tablespace.h b/src/include/commands/tablespace.h index 49cfc8479a..f33ba51bd6 100644 --- a/src/include/commands/tablespace.h +++ b/src/include/commands/tablespace.h @@ -19,6 +19,8 @@ #include "lib/stringinfo.h" #include "nodes/parsenodes.h" +extern bool allow_in_place_tablespaces; + /* XLOG stuff */ #define XLOG_TBLSPC_CREATE 0x00 #define XLOG_TBLSPC_DROP 0x10 -- 2.30.2