MDEV-13557: Startup failure, unable to decrypt ibdata1

Fixes also MDEV-13488: InnoDB writes CRYPT_INFO even though
encryption is not enabled.

Problem was that we created encryption metadata (crypt_data) for
system tablespace even when no encryption was enabled and too early.
System tablespace can be encrypted only using key rotation.

Test innodb-key-rotation-disable, innodb_encryption, innodb_lotoftables
require adjustment because INFORMATION_SCHEMA INNODB_TABLESPACES_ENCRYPTION
contain row only if tablespace really has encryption metadata.

fil_crypt_set_thread_cnt: Send message to background encryption threads
if they exits when they are ready. This is required to find tablespaces
requiring key rotation if no other changes happen.

fil_crypt_find_space_to_rotate: Decrease the amount of time waiting
when nothing happens to better enable key rotation on startup.

fsp_header_init: Write encryption metadata to page 0 only if tablespace is
encrypted or encryption is disabled by table option.

i_s_dict_fill_tablespaces_encryption : Skip tablespaces that do not
contain encryption metadata. This is required to avoid too early
wait condition trigger in encrypted -> unencrypted state transfer.

open_or_create_data_files: Do not create encryption metadata
by default to system tablespace.

1 files changed, 5 insertions, 1 deletions

diff --git a/storage/innobase/fsp/fsp0fsp.cc b/storage/innobase/fsp/fsp0fsp.cc
index 0b66856d2c3..1cf37f366d7 100644
--- a/storage/innobase/fsp/fsp0fsp.cc
+++ b/storage/innobase/fsp/fsp0fsp.cc
@@ -726,7 +726,11 @@ fsp_header_init(ulint space_id, ulint size, mtr_t* mtr)
 	fil_space_t* space = fil_space_acquire(space_id);
 	ut_ad(space);
 
-	if (space->crypt_data) {
+	/* Write encryption metadata to page 0 if tablespace is
+	encrypted or encryption is disabled by table option. */
+	if (space->crypt_data &&
+	    (space->crypt_data->should_encrypt() ||
+	     space->crypt_data->not_encrypted())) {
 		space->crypt_data->write_page0(page, mtr);
 	}