lkml.org 
[lkml]   [2022]   [Nov]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH AUTOSEL 6.0 24/44] scsi: scsi_debug: Make the READ CAPACITY response compliant with ZBC
Date
From: Bart Van Assche <bvanassche@acm.org>

[ Upstream commit ecb8c2580d37dbb641451049376d80c8afaa387f ]

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 <dgilbert@interlog.com>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Suggested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221102193248.3177608-1-bvanassche@acm.org
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 b8a76b89f85a..d474b3da8914 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) {
--
2.35.1
\
 
 \ /
  Last update: 2022-11-19 03:15    [W:0.229 / U:0.252 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site