4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ming Lei <ming.lei@xxxxxxxxxx> commit 2f31115e940c4afd49b99c33123534e2ac924ffb upstream. This patch introduces 'force_blk_mq' to the scsi_host_template so that drivers that have no desire to support the legacy I/O path can signal blk-mq only support. [mkp: commit desc] 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> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/hosts.c | 1 + include/scsi/scsi_host.h | 3 +++ 2 files changed, 4 insertions(+) --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -474,6 +474,7 @@ struct Scsi_Host *scsi_host_alloc(struct 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; device_initialize(&shost->shost_gendev); dev_set_name(&shost->shost_gendev, "host%d", shost->host_no); --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -452,6 +452,9 @@ struct scsi_host_template { /* True if the controller does not support WRITE SAME */ unsigned no_write_same:1; + /* True if the low-level driver supports blk-mq only */ + unsigned force_blk_mq:1; + /* * Countdown for host blocking with no commands outstanding. */