diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 9381171c2fc0..c72bce2f0cf1 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1666,10 +1666,11 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, blk_mq_start_request(req); } + cmd->flags &= SCMD_PRESERVED_FLAGS; if (sdev->simple_tags) cmd->flags |= SCMD_TAGGED; - else - cmd->flags &= ~SCMD_TAGGED; + if (bd->last) + cmd->flags |= SCMD_LAST; scsi_init_cmd_errh(cmd); cmd->scsi_done = scsi_mq_done; @@ -1807,10 +1808,37 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) } EXPORT_SYMBOL_GPL(__scsi_init_queue); +static const struct blk_mq_ops scsi_mq_ops_no_commit = { + .get_budget = scsi_mq_get_budget, + .put_budget = scsi_mq_put_budget, + .queue_rq = scsi_queue_rq, + .complete = scsi_softirq_done, + .timeout = scsi_timeout, +#ifdef CONFIG_BLK_DEBUG_FS + .show_rq = scsi_show_rq, +#endif + .init_request = scsi_mq_init_request, + .exit_request = scsi_mq_exit_request, + .initialize_rq_fn = scsi_initialize_rq, + .busy = scsi_mq_lld_busy, + .map_queues = scsi_map_queues, +}; + + +static void scsi_commit_rqs(struct blk_mq_hw_ctx *hctx) +{ + struct request_queue *q = hctx->queue; + struct scsi_device *sdev = q->queuedata; + struct Scsi_Host *shost = sdev->host; + + shost->hostt->commit_rqs(shost, hctx->queue_num); +} + static const struct blk_mq_ops scsi_mq_ops = { .get_budget = scsi_mq_get_budget, .put_budget = scsi_mq_put_budget, .queue_rq = scsi_queue_rq, + .commit_rqs = scsi_commit_rqs, .complete = scsi_softirq_done, .timeout = scsi_timeout, #ifdef CONFIG_BLK_DEBUG_FS @@ -1846,7 +1874,10 @@ int scsi_mq_setup_tags(struct Scsi_Host *shost) sizeof(struct scatterlist) * SCSI_INLINE_PROT_SG_CNT; memset(&shost->tag_set, 0, sizeof(shost->tag_set)); - shost->tag_set.ops = &scsi_mq_ops; + if (shost->hostt->commit_rqs) + shost->tag_set.ops = &scsi_mq_ops; + else + shost->tag_set.ops = &scsi_mq_ops_no_commit; shost->tag_set.nr_hw_queues = shost->nr_hw_queues ? : 1; shost->tag_set.queue_depth = shost->can_queue; shost->tag_set.cmd_size = cmd_size; diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index 76ed5e4acd38..91bd749a02f7 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -57,6 +57,7 @@ struct scsi_pointer { #define SCMD_TAGGED (1 << 0) #define SCMD_UNCHECKED_ISA_DMA (1 << 1) #define SCMD_INITIALIZED (1 << 2) +#define SCMD_LAST (1 << 3) /* flags preserved across unprep / reprep */ #define SCMD_PRESERVED_FLAGS (SCMD_UNCHECKED_ISA_DMA | SCMD_INITIALIZED) diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index cc139dbd71e5..31e0d6ca1eba 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -80,8 +80,10 @@ struct scsi_host_template { * command block to the LLDD. When the driver finished * processing the command the done callback is invoked. * - * If queuecommand returns 0, then the HBA has accepted the - * command. The done() function must be called on the command + * If queuecommand returns 0, then the driver has accepted the + * command. It must also push it to the HBA if the scsi_cmnd + * flag SCMD_LAST is set, or if the driver does not implement + * commit_rqs. The done() function must be called on the command * when the driver has finished with it. (you may call done on the * command before queuecommand returns, but in this case you * *must* return 0 from queuecommand). @@ -109,6 +111,16 @@ struct scsi_host_template { */ int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); + /* + * The commit_rqs function is used to trigger a hardware + * doorbell after some requests have been queued with + * queuecommand, when an error is encountered before sending + * the request with SCMD_LAST set. + * + * STATUS: OPTIONAL + */ + void (*commit_rqs)(struct Scsi_Host *, u16); + /* * This is an error handling strategy routine. You don't need to * define one of these if you don't want to - there is a default