On Fri, Mar 09, 2018 at 11:32:17AM +0800, Ming Lei wrote: > >From scsi driver view, it is a bit troublesome to support both blk-mq > and non-blk-mq at the same time, especially when drivers need to support > multi hw-queue. > > This patch introduces 'force_blk_mq' to scsi_host_template so that drivers > can provide blk-mq only support, so driver code can avoid the trouble > for supporting both. > > Cc: Omar Sandoval <osandov@xxxxxx>, > Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>, > Cc: James Bottomley <james.bottomley@xxxxxxxxxxxxxxxxxxxxx>, > Cc: Christoph Hellwig <hch@xxxxxx>, > Cc: Don Brace <don.brace@xxxxxxxxxxxxx> > Cc: Kashyap Desai <kashyap.desai@xxxxxxxxxxxx> > Cc: Mike Snitzer <snitzer@xxxxxxxxxx> > Cc: Laurence Oberman <loberman@xxxxxxxxxx> > Reviewed-by: Hannes Reinecke <hare@xxxxxxx> > Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> > --- > drivers/scsi/hosts.c | 1 + > include/scsi/scsi_host.h | 3 +++ > 2 files changed, 4 insertions(+) > > diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c > index 57bf43e34863..10f04b089392 100644 > --- a/drivers/scsi/hosts.c > +++ b/drivers/scsi/hosts.c > @@ -477,6 +477,7 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize) > shost->dma_boundary = 0xffffffff; > > shost->use_blk_mq = scsi_use_blk_mq; > + shost->use_blk_mq = scsi_use_blk_mq || !!shost->hostt->force_blk_mq; No need for the !! here. Otherwise looks good: Reviewed-by: Christoph Hellwig <hch@xxxxxx>