don't GRANT UPDATE ON mysql.global_priv TO mariadb.sys@localhost;

Classes that handle privilege tables (like Tables_priv_table)
could read some columns conditionally but they expect a certain
minimal number of colunms always to exist.

Add a check for a minimal required number of columns in privilege tables,
don't use a table that has fewer columns than required.

1. Fixing ROUND(x) and TRUNCATE(x,0) with TINYINT, SMALLINT, MEDIUMINT, BIGINT
   input to preserve the exact data type of the argument when it's possible.

2. Fixing FLOOR(x) and CEILING(x) with TINYINT, SMALLINT, MEDIUMINT, BIGINT
  to preserve the exact data type of the argument.

3. Adding dedicated Type_handler_year::Item_func_round_fix_length_and_dec()
  to easier handle ROUND(x) and TRUNCATE(x,y) for the YEAR(2) and YEAR(4)
  input. They still return INT(2) UNSIGNED and INT(4) UNSIGNED correspondingly,
  as before.

Implementing dedicated fixing methods:
- Type_handler_bit::Item_func_round_fix_length_and_dec()
- Type_handler_bit::Item_func_int_val_fix_length_and_dec()
- Type_handler_typelib::Item_func_round_fix_length_and_dec()

because the inherited methods did not work well.

Fixing:
- Type_handler_typelib::Item_func_int_val_fix_length_and_dec
  It did not work well, because it used args[0]->max_length to
  calculate the result data type. In case of ENUM and SET it was
  not correct, because in FLOOR() and CEILING() context
  ENUM and SET return not more than 5 digits (65535 is the biggest
  possible value).

Misc:
- Changing the API of
    Type_handler_bit::Bit_decimal_notation_int_digits(const Item *item)
  to a more generic form:
    Type_handler_bit::Bit_decimal_notation_int_digits_by_nbits(uint nbits)

- Fixing Type_handler_bit::Bit_decimal_notation_int_digits_by_nbits() to
  return the exact number of decimal digits for all nbits 1..64.
  The old implementation was approximate.
  This change gives better (more precise) data types.

- Type_handler_hex_hybrid did not override
  Type_handler_string_result::Item_func_round_fix_length_and_dec(),
  so the result type of ROUND(0xFFFFFFFFFFFFFFFF) was erroneously
  calculated ad DOUBLE with a wrong length.
  Overriding Item_func_round_fix_length_and_dec(), to calculated
  the result type as INT/BIGINT.

  Also, fixing Item_func_round::fix_arg_int() to use
  args[0]->decimal_precision() instead of args[0]->max_length
  when calculating this->max_length, to get a correct result
  for hex hybrids.

- Type_handler_hex_hybrid::Item_func_int_val_fix_length_and_dec()
  called item->fix_length_and_dec_int_or_decimal(), which did not
  produce a correct result data type for hex hybrid.
  Implementing a dedicated code instead, to return INT UNSIGNED or
  BIGINT UNSIGNED depending in the number of digits in the arguments.

Doesn't allow instant alter of a field which is a prefix part of some key

is_part_of_a_key_prefix(): I hope the name of the function is clear

ha_innobase::can_convert_string()
ha_innobase::can_convert_varstring()
ha_innobase::can_convert_blob(): it can't when field is_part_of_a_key_prefix()

Fixing functions CEILING and FLOOR to return
- TIME for TIME input
- DATETIME for DATETIME and TIMESTAMP input

Continue support the hack of current select equal builtin select if
selects stack is empty even after subselects.

An instant ADD/DROP/reorder column could create a dummy table
object with the wrong ROW_FORMAT when innodb_default_row_format
was changed between CREATE TABLE and ALTER TABLE.

prepare_inplace_alter_table_dict(): If we had promised that
ALGORITHM=INPLACE is supported, we must preserve the ROW_FORMAT.

dict_table_t::prepare_instant(): Add debug assertions to catch
ROW_FORMAT mismatch.

The rest of the changes are related to adding
Alter_inplace_info::inplace_supported to cache the return value of
handler::check_if_supported_inplace_alter().

mutex was already locked upon startup with server_audit and orphan
records in mysql.plugin.

Preaquire auditing plugins before LOCK_plugin to awoid double locking.

In commit 0e5a4ac2 (MDEV-15562)
we introduced a bogus debug assertion, demanding that dict_col_t::len
never exceed some maximum value. The intention was to match what
dict_index_add_col() is doing. But, the assignment field->fixed_len = 0
applies to dict_field_t::fixed_len, not dict_col_t::len!

An assertion

  `server_state_.rollback_mode() == wsrep::server_state::rm_async`

fired in before_command() when
- thread-handling was set to pool-of-threads and
- a BF abort happened between client session calls to
  wait_rollback_complete_and_acquire_ownership() and before_command().

This commit introduces a test case to reproduce the crash and
updates wsrep-lib submodule to fixed version.

The sporadic test hangs happen because of mutex dealock between innodb
background threads and two test connection executions.
The test sets variable innodb_disallow_writes, which blocks all writes
to filesyste. The test logic is to execute an INSERT, which should hang
because of filesytstem writes are blocked, and through another session
verify by SELECT that this hanging happens. The SELECT session will then
release innodb_disallow_writes blocking.

However, filesystem write  blocking affects also innodb background threads
and they may hang while keeping some other resources locked.
As an example, in one test hang situation, buffer pool access was blocked.
And, if buffer pool is blocked, the test connections will be blocked as well,
and the SELECT session will not be able to continue to release the
innodb_disallow_writes.

The fix in this commit is refactoring of the test logic.
The test will now set first innodb_disallow_writes blocking, and then record
a hash of data directory's filesystem contents. This works as checksum of the
state of data on the datadirectory.

Then some SQL load is tried on both nodes, these sessions will be blocking
due to frozen file system state. The test will have a short sleep to allow
innodb background threads to loop and possibly encounter innodb_disallow_writes
blocking as well.

After the sleep, the test will record file system checksun for the second time,
and then release the innodb_disallow-writes blocking.

Finally, the two checksums are compared, they should be identical to verify that
nothing was written on datadirectory during the test execution.

The checksum is implemented by md5sum hash over all files found in datadirectory
by find command. all these file hashes are hashed together by one more md5sum.

The test therefore depends on md5sum and find. find may work differently with some
OS distributions, e.g. freebsd may be problematic.

MDEV-22458: Server with WSREP hangs after INSERT, wrong usage of mutex 'LOCK_thd_data' and 'share->intern_lock' / 'lock->mutex'

Add `find_thread_by_id_with_thd_data_lock` which will be used only when killing thread.
This version needs to take `thd->LOCK_thd_data` lock.

Fixed wsrep_notify.sh script so it only reports status changes on
'joined', 'synced', 'donor'.

outline-atomics compilation flag changes behaviour of builtin_atomics,
by adding runtime detection of LSE atomics. If these are supported, they
will be used. This gains LSE atomics use without hurting compatibility
with older aarch64 machines.

aarch64 timer is available to userspace via arch register.
clang's __builtin_readcyclecounter is wrong for aarch64 (reads the PMU
cycle counter instead of the archi-timer register), so we don't use it.

my_rdtsc unit-test on AWS m6g shows:
frequency: 121830845
resolution: 1
overhead: 1

This counter is not strictly increasing, but it is non-decreasing.

Starting with MDEV-17441 we would no longer have os_once,
and we would always initialize zip_pad_info_t::mutex and
dict_table_t::autoinc_mutex, even for tables are not in
ROW_FORMAT=COMPRESSED nor include any AUTO_INCREMENT column.

mutex_free() on those unnecessary objects would make shutdown very slow
compared to older versions.

Let us use std::mutex for those two mutexes, to reduce the overhead.
The critical sections protected by these mutexes is very small, and
therefore contention or the need for any instrumentation should
be unlikely.

If there is no current_select and variable is not found among SP variables it can be only an error.

InnoDB should replace FSP_FLAGS_HAS_PAGE_COMPRESSION check with
fil_space_t::is_compressed(). fil_space_t::is_compressed() checks
for both non full crc32 and crc32 format.

trx_update_mod_tables_timestamp(): When implementing
innodb_evict_tables_on_commit_debug, do not evict tables
on which transactional locks exist.

This debug variable was broken since its introduction in
commit 947b0b57.

Problem was that the code didn't handle a transaction created in innodb
as part of a failed mysql_lock_tables()

The issue was:
T1, a parallel slave worker thread, is waiting for another worker thread to
commit. While waiting, it has the MDL_BACKUP_COMMIT lock.
T2, working for mariabackup, is doing BACKUP STAGE BLOCK_COMMIT and blocks
all commits.
This causes a deadlock as the thread T1 is waiting for can't commit.

Fixed by moving locking of MDL_BACKUP_COMMIT from ha_commit_trans() to
commit_one_phase_2()

Other things:
- Added a new argument to ha_comit_one_phase() to signal if the
  transaction was a write transaction.
- Ensured that ha_maria::implicit_commit() is always called under
  MDL_BACKUP_COMMIT. This code is not needed in 10.5
- Ensure that MDL_Request values 'type' and 'ticket' are always
  initialized. This makes it easier to check the state of the MDL_Request.
- Moved thd->store_globals() earlier in handle_rpl_parallel_thread() as
  thd->init_for_queries() could use a MDL that could crash if store_globals
  where not called.
- Don't call ha_enable_transactions() in THD::init_for_queries() as this
  is both slow (uses MDL locks) and not needed.

MDEV-22899 Assertion `field->col->is_binary() || field->prefix_len % field->col->mbmaxlen == 0' failed in dict_index_add_to_cache

is_part_of_a_key(): detect is TEXT field is a part of some key

ha_innobase::can_convert_blob(): now correctly detect whether our blob
is a part of some key. Previously the check didn't work in some cases.

Fix stale virtual field value in 4 cases: when virtual field depends
on row_start/row_end in timestamp/trx_id versioned table. row_start
dep is recalculated in vers_update_fields() (SQL and InnoDB
layer). row_end dep is recalculated on history row insert.

MDEV-22061 InnoDB: Assertion of missing row in sec index row_start upon REPLACE on a system-versioned table

make_versioned_helper() appended new update field unconditionally
while it should check if this field already exists in update vector.

Misc renames to conform versioning prefix. vers_update_fields() name
conforms with sql layer TABLE::vers_update_fields().