When device used as cache had a big size, it took a lot of time to initialize.
If user would interrupt waiting, asyc OCF init procedure would continue, but
after finish, there was nobody to perfrom kernel part of start nor error
handling.
Now error handling and kernel part of start procedure are moved to completion.
If user will interrupt waiting at any point, newly started cache instance will
be stopped.
Since cache init and load vary only with check for old metadata and initializing
exported objects, they are now merged into one function.
Async cache stop is part of this commit because it was needed for rollback path.
Load, init and stop have common context, because in case of non interrupted
attach CAS needs to wait for rollback to be completed. Common context makes
passing `struct completion` easier between load, init and stop.
This commit is part of patch that will allow to interrupt waiting for OCF
operations.
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
232f13a8a4