On 19/11/2021 19:57, Bart Van Assche wrote:
+/**
+ * scsi_get_internal_cmd - Allocate an internal SCSI command
+ * @q: request queue from which to allocate the command. This request queue may
+ * but does not have to be associated with a SCSI device. This request
+ * queue must be associated with a SCSI tag set. See also
+ * scsi_mq_setup_tags().
+ * @data_direction: Data direction for the allocated command.
+ * @flags: Zero or more BLK_MQ_REQ_* flags.
+ *
+ * Allocates a request for driver-internal use. The tag of the returned SCSI
+ * command is guaranteed to be unique.
+ */
+struct scsi_cmnd *scsi_get_internal_cmd(struct request_queue *q,
+ enum dma_data_direction data_direction,
+ blk_mq_req_flags_t flags)
I'd pass the Scsi_Host or scsi_device rather than a request q, so maybe:
struct scsi_cmnd *scsi_get_internal_cmd(struct scsi_device *sdev, ..)
struct scsi_cmnd *scsi_host_get_internal_cmd(struct Scsi_Host *shost, ..)
+{
+ unsigned int opf = REQ_INTERNAL;
+ struct request *rq;
+
+ opf |= data_direction == DMA_TO_DEVICE ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN;
+ rq = blk_mq_alloc_request(q, opf, flags);
+ if (IS_ERR(rq))
+ return ERR_CAST(rq);
I think that Christoph suggested elsewhere that we should poison all the
scsi_cmnd
+ return blk_mq_rq_to_pdu(rq);
+}
+EXPORT_SYMBOL_GPL(scsi_get_internal_cmd);
