[dm-devel] [PATCH 05/15] dm: remove incomple BLOCK_PC support

Thu Jan 12 08:00:54 UTC 2017

On Wed, Jan 11, 2017 at 08:09:37PM -0500, Mike Snitzer wrote:
> I'm not following your reasoning.
> 
> dm_blk_ioctl calls __blkdev_driver_ioctl and will call scsi_cmd_ioctl
> (sd_ioctl -> scsi_cmd_blk_ioctl -> scsi_cmd_ioctl) if DM's underlying
> block device is a scsi device.

Yes, it it does.  But scsi_cmd_ioctl as called from sd_ioctl will
operate entirely on the SCSI request_queue - dm-mpath will never see
the BLOCK_PC request generated by it.