Revert "Allow on-line enabling and disabling of data checksums"

This reverts the backend sides of commit 1fde38beaa0c3e66c340efc7cc0dc272d6254bb0.
I have, at least for now, left the pg_verify_checksums tool in place, as
this tool can be very valuable without the rest of the patch as well,
and since it's a read-only tool that only runs when the cluster is down
it should be a lot safer.

1 files changed, 0 insertions, 59 deletions

diff --git a/src/backend/access/transam/xlogfuncs.c b/src/backend/access/transam/xlogfuncs.c
index b76b2688911..316edbe3c58 100644
--- a/src/backend/access/transam/xlogfuncs.c
+++ b/src/backend/access/transam/xlogfuncs.c
@@ -24,7 +24,6 @@
 #include "catalog/pg_type.h"
 #include "funcapi.h"
 #include "miscadmin.h"
-#include "postmaster/checksumhelper.h"
 #include "replication/walreceiver.h"
 #include "storage/smgr.h"
 #include "utils/builtins.h"
@@ -699,61 +698,3 @@ pg_backup_start_time(PG_FUNCTION_ARGS)
 
 	PG_RETURN_DATUM(xtime);
 }
-
-/*
- * Disables checksums for the cluster, unless already disabled.
- *
- * Has immediate effect - the checksums are set to off right away.
- */
-Datum
-disable_data_checksums(PG_FUNCTION_ARGS)
-{
-	/*
-	 * If we don't need to write new checksums, then clearly they are already
-	 * disabled.
-	 */
-	if (!DataChecksumsNeedWrite())
-		ereport(ERROR,
-				(errmsg("data checksums already disabled")));
-
-	ShutdownChecksumHelperIfRunning();
-
-	SetDataChecksumsOff();
-
-	PG_RETURN_VOID();
-}
-
-/*
- * Enables checksums for the cluster, unless already enabled.
- *
- * Supports vacuum-like cost-based throttling, to limit system load.
- * Starts a background worker that updates checksums on existing data.
- */
-Datum
-enable_data_checksums(PG_FUNCTION_ARGS)
-{
-	int			cost_delay = PG_GETARG_INT32(0);
-	int			cost_limit = PG_GETARG_INT32(1);
-
-	if (cost_delay < 0)
-		ereport(ERROR,
-				(errmsg("cost delay cannot be less than zero")));
-	if (cost_limit <= 0)
-		ereport(ERROR,
-				(errmsg("cost limit must be a positive value")));
-
-	/*
-	 * Allow state change from "off" or from "inprogress", since this is how
-	 * we restart the worker if necessary.
-	 */
-	if (DataChecksumsNeedVerify())
-		ereport(ERROR,
-				(errmsg("data checksums already enabled")));
-
-	SetDataChecksumsInProgress();
-	if (!StartChecksumHelperLauncher(cost_delay, cost_limit))
-		ereport(ERROR,
-				(errmsg("failed to start checksum helper process")));
-
-	PG_RETURN_VOID();
-}