scsi: core: Drop Scsi_Host.default_lock

Back in the 2.6.xx days, it was possible to for low-level drivers to set
the shost lock pointer. That is why there is a default lock and a
pointer to the shost lock.

However, support for this has long been removed, so drop
Scsi_Host.default_lock and make Scsi_Host.host_lock as the actual lock.

Getting the address of embedded host_lock structure just requires adding
a fixed offset value to the shost pointer. However, getting the value of
the host_lock pointer requires loading from a fixed offset to the shost
pointer. The latter should be very slightly slower, which is relevant as
this lock is used a lot throughout the core code and drivers.

Signed-off-by: John Garry <john.garry@linux.dev>
Acked-by: Damien Le Moal <dlemoal@kernel.org> # ata parts
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20260831095821.3486994-1-john.g.garry@oracle.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>

0 files changed, 0 insertions, 0 deletions