block: Change elevator_init_mq() to always succeed

If the default elevator chosen is mq-deadline, elevator_init_mq() may
return an error if mq-deadline initialization fails, leading to
blk_mq_init_allocated_queue() returning an error, which in turn will
cause the block device initialization to fail and the device not being
exposed.

Instead of taking such extreme measure, handle mq-deadline
initialization failures in the same manner as when mq-deadline is not
available (no module to load), that is, default to the "none" scheduler.
With this change, elevator_init_mq() return type can be changed to void.

Reviewed-by: Johannes Thumshirn <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ming Lei <[email protected]>
Signed-off-by: Damien Le Moal <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

0 files changed, 0 insertions, 0 deletions