From ecb8c2580d37dbb641451049376d80c8afaa387f Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Wed, 2 Nov 2022 12:32:48 -0700 Subject: [PATCH] scsi: scsi_debug: Make the READ CAPACITY response compliant with ZBC From ZBC-1: - RC BASIS = 0: The RETURNED LOGICAL BLOCK ADDRESS field indicates the highest LBA of a contiguous range of zones that are not sequential write required zones starting with the first zone. - RC BASIS = 1: The RETURNED LOGICAL BLOCK ADDRESS field indicates the LBA of the last logical block on the logical unit. The current scsi_debug READ CAPACITY response does not comply with the above if there are one or more sequential write required zones. SCSI initiators need a way to retrieve the largest valid LBA from SCSI devices. Reporting the largest valid LBA if there are one or more sequential zones requires to set the RC BASIS field in the READ CAPACITY response to one. Hence this patch. Cc: Douglas Gilbert Cc: Damien Le Moal Suggested-by: Damien Le Moal Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20221102193248.3177608-1-bvanassche@acm.org Reviewed-by: Damien Le Moal Acked-by: Douglas Gilbert Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_debug.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 697fc57bc711f..629853662b820 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -1899,6 +1899,13 @@ static int resp_readcap16(struct scsi_cmnd *scp, arr[14] |= 0x40; } + /* + * Since the scsi_debug READ CAPACITY implementation always reports the + * total disk capacity, set RC BASIS = 1 for host-managed ZBC devices. + */ + if (devip->zmodel == BLK_ZONED_HM) + arr[12] |= 1 << 4; + arr[15] = sdebug_lowest_aligned & 0xff; if (have_dif_prot) { -- 2.39.5