From: Laurence Oberman <loberman@redhat.com>
Date: Sat, 3 Feb 2018 13:38:35 -0500
Subject: [PATCH] scsi: scsi_debug: Add two new parameters to scsi_debug driver
Git-commit: d9da891a892a38db4ec7abcc2df57f9ae3777d99
Patch-mainline: v4.17-rc1
References: bsc#1118139
This patch adds two new parameters to the scsi_debug driver.
During various fault injection scenarios it would be useful to be able
to pick a specific starting sector and number of follow on sectors where
a MEDIUM ERROR for reads would be returned against a scsi-debug device.
Right now this only works against sector 0x1234 and OPT_MEDIUM_ERR_NUM
follow on sectors. However during testing of md-raid and other
scenarios I wanted more flexibility.
The idea is add 2 new parameters:
medium_error_start
medium_error_count
If medium_error_start is set then we don't use the default of
OPT_MEDIUM_ERR_ADDR, but use that set value.
If medium_error_count is set we use that value otherwise default to
OPT_MEDIUM_ERR_NUM.
Signed-off-by: Laurence Oberman <loberman@redhat.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/scsi_debug.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 7d2ce0cc915a..8480e4849e29 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -616,6 +616,8 @@ static unsigned int sdebug_guard = DEF_GUARD;
static int sdebug_lowest_aligned = DEF_LOWEST_ALIGNED;
static int sdebug_max_luns = DEF_MAX_LUNS;
static int sdebug_max_queue = SDEBUG_CANQUEUE; /* per submit queue */
+static unsigned int sdebug_medium_error_start = OPT_MEDIUM_ERR_ADDR;
+static int sdebug_medium_error_count = OPT_MEDIUM_ERR_NUM;
static atomic_t retired_max_queue; /* if > 0 then was prior max_queue */
static int sdebug_ndelay = DEF_NDELAY; /* if > 0 then unit is nanoseconds */
static int sdebug_no_lun_0 = DEF_NO_LUN_0;
@@ -2711,8 +2713,8 @@ static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
}
if (unlikely((SDEBUG_OPT_MEDIUM_ERR & sdebug_opts) &&
- (lba <= (OPT_MEDIUM_ERR_ADDR + OPT_MEDIUM_ERR_NUM - 1)) &&
- ((lba + num) > OPT_MEDIUM_ERR_ADDR))) {
+ (lba <= (sdebug_medium_error_start + sdebug_medium_error_count - 1)) &&
+ ((lba + num) > sdebug_medium_error_start))) {
/* claim unrecoverable read error */
mk_sense_buffer(scp, MEDIUM_ERROR, UNRECOVERED_READ_ERR, 0);
/* set info field and valid bit for fixed descriptor */
@@ -4432,6 +4434,8 @@ module_param_named(lbprz, sdebug_lbprz, int, S_IRUGO);
module_param_named(lowest_aligned, sdebug_lowest_aligned, int, S_IRUGO);
module_param_named(max_luns, sdebug_max_luns, int, S_IRUGO | S_IWUSR);
module_param_named(max_queue, sdebug_max_queue, int, S_IRUGO | S_IWUSR);
+module_param_named(medium_error_start, sdebug_medium_error_start, int, S_IRUGO | S_IWUSR);
+module_param_named(medium_error_count, sdebug_medium_error_count, int, S_IRUGO | S_IWUSR);
module_param_named(ndelay, sdebug_ndelay, int, S_IRUGO | S_IWUSR);
module_param_named(no_lun_0, sdebug_no_lun_0, int, S_IRUGO | S_IWUSR);
module_param_named(no_uld, sdebug_no_uld, int, S_IRUGO);
@@ -4489,6 +4493,8 @@ MODULE_PARM_DESC(lbprz,
MODULE_PARM_DESC(lowest_aligned, "lowest aligned lba (def=0)");
MODULE_PARM_DESC(max_luns, "number of LUNs per target to simulate(def=1)");
MODULE_PARM_DESC(max_queue, "max number of queued commands (1 to max(def))");
+MODULE_PARM_DESC(medium_error_start, "starting sector number to return MEDIUM error");
+MODULE_PARM_DESC(medium_error_count, "count of sectors to return follow on MEDIUM error");
MODULE_PARM_DESC(ndelay, "response delay in nanoseconds (def=0 -> ignore)");
MODULE_PARM_DESC(no_lun_0, "no LU number 0 (def=0 -> have lun 0)");
MODULE_PARM_DESC(no_uld, "stop ULD (e.g. sd driver) attaching (def=0))");
--
2.12.3