On Fri, 2017-09-15 at 19:06 +0900, Damien Le Moal wrote: > + * There is no write constraints on conventional zones. So any write ^^^^^^^^^^^ Should this have been "There are no"? > - if (sdkp->zones_wlock && > - test_and_set_bit(zno, sdkp->zones_wlock)) > + if (q->zoned.seq_zones && test_bit(zno, q->zoned.seq_zones)) > + return BLKPREP_OK; > + if (sdkp->zones_wlock && test_and_set_bit(zno, sdkp->zones_wlock)) > return BLKPREP_DEFER; Please introduce helper functions in include/linux/blkdev.h or in a new header file for verifying whether or not a zone is a sequential zone and also for locking a zone for writes. I expect that that will make the above code significantly easier to read. Thanks, Bart.