[PATCH V2 05/13] block: only account passthrough IO from userspace

[Christoph Hellwig]

On Sat, Jan 22, 2022 at 07:10:46PM +0800, Ming Lei wrote:
> Passthrough request from userspace has one active block_device/disk
> associated, so they can be accounted via rq->q->disk. For other
> passthrough request, there may not be disk/block_device for the queue,
> since either the queue has not a disk or the disk may be deleted
> already.
> 
> Add flag of BLK_MQ_REQ_USER_IO for only accounting passthrough request
> from userspace.

Please explain why you want to change this.

Also this is missing I/O from /dev/sg, CDROM CDDA BPC reading, the tape
drivers and bsg-lib.