MySQL 5.6 do not work with MariaDB 10.1
Analysis: Problem is that tablespace flags bit DATA_DIR
is on different position on MySQL 5.6 compared to
MariaDB 10.1.
Fix: If we detect that there is difference between dictionary
flags and tablespace flags we remove DATA_DIR flag and compare
again. Remote tablespace is tried to locate even in case
when DATA_DIR flag is not set.
Problem was that link file (.isl) is also opened using O_DIRECT
mode and if this fails the whole create table fails on internal
error.
Fixed by not using O_DIRECT on link files as they are used only
on create table and startup and do not contain real data.
O_DIRECT failures are successfully ignored for data files
if O_DIRECT is not supported by file system on used
data directory.
Analysis: Lengths which are not UNIV_SQL_NULL, but bigger than the following
number indicate that a field contains a reference to an externally
stored part of the field in the tablespace. The length field then
contains the sum of the following flag and the locally stored len.
This was incorrectly set to
define UNIV_EXTERN_STORAGE_FIELD (UNIV_SQL_NULL - UNIV_PAGE_SIZE_MAX)
When it should be
define UNIV_EXTERN_STORAGE_FIELD (UNIV_SQL_NULL - UNIV_PAGE_SIZE_DEF)
Additionally, we need to disable support for > 16K page size for
row compressed tables because a compressed page directory entry
reserves 14 bits for the start offset and 2 bits for flags.
This limits the uncompressed page size to 16k. To support
larger pages page directory entry needs to be larger.
Analysis: Problem is that punch hole does not know the actual page size
of the page and does the page belong to an data file or to a log file.
Fix: Pass down the file type and page size to os layer to be used
when trim is called. Also fix unsafe null pointer access to
actual write_size.
Added encryption support for online alter table where InnoDB temporary
files are used. Added similar support also for tables containing
full text-indexes.
Made sure that table remains encrypted during discard and import
tablespace.
Analysis: Problem was that in fil_read_first_page we do find that
table has encryption information and that encryption service
or used key_id is not available. But, then we just printed
fatal error message that causes above assertion.
Fix: When we open single table tablespace if it has encryption
information (crypt_data) store this crypt data to the table
structure. When we open a table and we find out that tablespace
is not available, check has table a encryption information
and from there is encryption service or used key_id is not available.
If it is, add additional warning for SQL-layer.
Analysis: Problem was that when a new tablespace is created a default
encryption info is also created and stored to the tablespace. Later a
new encryption information was created with correct key_id but that
does not affect on IV.
Fix: Push encryption mode and key_id to lower levels and create
correct encryption info when a new tablespace is created.
This fix does not contain test case because, currently incorrect
encryption key causes page corruption and a lot of error messages
to error log causing mtr to fail.
Analysis: In fil_crypt_space_needs_rotation we first make sure that
tablespace is found and then separately that it is normal tablespace.
Thus, tablespace could be dropped between these two functions calls.
Fix: If space is not found from fil_system return tablespace type
ULINT_UNDEFINED and naturally do not continue rotating space.
Analysis: Problem was that we did try to read from tablespace
that was being dropped.
Fixed by introducing a new function to find a tablespace only
if it is not being dropped currently and adding this check
before trying to read pages from tablespace.
Analysis: At fil_spage_get_space there is small change that space
is found from tablespace list but we have not yet created node
for it (and added it to space->chain) and as we hold fil_system
mutex here fil_node_create can't continue.
Fixed by allowing UT_LIST_GET_LEN(space->chain) == 0|| 1 and
introducint two new functions that access filespace list
and before returning space check that node is also created.
Make sure that when we publish the crypt_data we access the
memory cache of the tablespace crypt_data. Make sure that
crypt_data is stored whenever it is really needed.
All this is not yet enough in my opinion because:
sql/encryption.cc has DBUG_ASSERT(scheme->type == 1) i.e.
crypt_data->type == CRYPT_SCHEME_1
However, for InnoDB point of view we have global crypt_data
for every tablespace. When we change variables on crypt_data
we take mutex. However, when we use crypt_data for
encryption/decryption we use pointer to this global
structure and no mutex to protect against changes on
crypt_data.
Tablespace encryption starts in fil_crypt_start_encrypting_space
from crypt_data that has crypt_data->type = CRYPT_SCHEME_UNENCRYPTED
and later we write page 0 CRYPT_SCHEME_1 and finally whe publish
that to memory cache.
Analysis: Problem was that tablespaces not encrypted might not have
crypt_data stored on disk.
Fixed by always creating crypt_data to memory cache of the tablespace.
MDEV-8138: strange results from encrypt-and-grep test
Analysis: crypt_data->type is not updated correctly on memory
cache. This caused problem with state tranfer on
encrypted => unencrypted => encrypted.
Fixed by updating memory cache of crypt_data->type correctly based on
current srv_encrypt_tables value to either CRYPT_SCHEME_1 or
CRYPT_SCHEME_UNENCRYPTED.
Analysis: Problem was that we did create crypt data for encrypted table but
this new crypt data was not written to page 0. Instead a default crypt data
was written to page 0 at table creation.
Fixed by explicitly writing new crypt data to page 0 after successfull
table creation.
With changes:
* update tests to pass (new encryption/encryption_key_id syntax).
* not merged the code that makes engine aware of the encryption mode
(CRYPT_SCHEME_1_CBC, CRYPT_SCHEME_1_CTR, storing it on disk, etc),
because now the encryption plugin is handling it.
* compression+encryption did not work in either branch before the
merge - and it does not work after the merge. it might be more
broken after the merge though - some of that code was not merged.
* page checksumming code was not moved (moving of page checksumming
from fil_space_encrypt() to fil_space_decrypt was not merged).
* restored deleted lines in buf_page_get_frame(), otherwise
innodb_scrub test failed.
Step 3:
-- Make encrytion_algorithm changeable by SUPER
-- Remove AES_ECB method from encryption_algorithms
-- Support AES method change by storing used method on InnoDB/XtraDB objects
-- Store used AES method to crypt_data as different crypt types
-- Store used AES method to redo/undo logs and checkpoint
-- Store used AES method on every encrypted page after key_version
-- Add test
Step 2:
-- Introduce temporal memory array to buffer pool where to allocate
temporary memory for encryption/compression
-- Rename PAGE_ENCRYPTION -> ENCRYPTION
-- Rename PAGE_ENCRYPTION_KEY -> ENCRYPTION_KEY
-- Rename innodb_default_page_encryption_key -> innodb_default_encryption_key
-- Allow enable/disable encryption for tables by changing
ENCRYPTION to enum having values DEFAULT, ON, OFF
-- In create table store crypt_data if ENCRYPTION is ON or OFF
-- Do not crypt tablespaces having ENCRYPTION=OFF
-- Store encryption mode to crypt_data and redo-log
Step 1:
-- Remove page encryption from dictionary (per table
encryption will be handled by storing crypt_data to page 0)
-- Remove encryption/compression from os0file and all functions
before that (compression will be added to buf0buf.cc)
-- Use same CRYPT_SCHEME_1 for all encryption methods
-- Do some code cleanups to confort InnoDB coding style
