Hi all, this series splits the support for SCSI passthrough commands from the main struct request used all over the block layer into a separate scsi_request structure that drivers that want to support SCSI passthough need to embedded as the first thing into their request-private data, similar to how we handle NVMe passthrough commands. To support this I've added support for that the private data after request structure to the legacy request path instead, so that it can be treated the same way as the blk-mq path. Compare to the current scsi_cmnd allocator that actually is a major simplification. There is one major show-stopper for the series as-is: Request-based device mapper currently allocate the request structures in the stacking driver without a knowledge of the queue it's going to be submitte on for the legacy request path. It managed to avoid that issue for the blk-mq path, but that currently can't be used on legacy request devices for reasons I don't fully understand. We'll need to figure out how sort this out, but maybe that's a good opportunity to drop one or two of the three different dm-mpath I/O paths? :) Note that the first two patches are 4.10 material and have already been submitted independently. -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
