If a fail commnd error is injected, set the command's status and sense
data then finish this scsi command.
Set SCSI command's status and sense data format:
+--------+------+-------------------------------------------------------+
| Column | Type | Description |
+--------+------+-------------------------------------------------------+
| 1 | u8 | Error type, fixed to 0x2 |
+--------+------+-------------------------------------------------------+
| 2 | s32 | Error Count |
| | | 0: the rule will be ignored |
| | | positive: the rule will always take effect |
| | | negative: the rule takes effect n times where -n is |
| | | the value given. Ignored after n times |
+--------+------+-------------------------------------------------------+
| 3 | x8 | SCSI command opcode, 0xff for all commands |
+--------+------+-------------------------------------------------------+
| 4 | x8 | Host byte in scsi_cmd::status |
| | | [scsi_cmd::status has 32 bits holding these 3 bytes] |
+--------+------+-------------------------------------------------------+
| 5 | x8 | Driver byte in scsi_cmd::status |
+--------+------+-------------------------------------------------------+
| 6 | x8 | SCSI Status byte in scsi_cmd::status |
+--------+------+-------------------------------------------------------+
| 7 | x8 | SCSI Sense Key in scsi_cmnd |
+--------+------+-------------------------------------------------------+
| 8 | x8 | SCSI ASC in scsi_cmnd |
+--------+------+-------------------------------------------------------+
| 9 | x8 | SCSI ASCQ in scsi_cmnd |
+--------+------+-------------------------------------------------------+
Examples:
error=/sys/kernel/debug/scsi_debug/0:0:0:1/error
echo "2 -10 0x88 0 0 0x2 0x3 0x11 0x0" >${error}
will make device's read command return with media error with additional
sense of "Unrecovered read error" (UNC):
Signed-off-by: Wenchao Hao <haowenchao2@xxxxxxxxxx>
Acked-by: Douglas Gilbert <dgilbert@xxxxxxxxxxxx>
---
drivers/scsi/scsi_debug.c | 46 +++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 1d28e7209f64..94c43b800694 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -7763,6 +7763,41 @@ static int sdebug_fail_queue_cmd(struct scsi_cmnd *cmnd)
return 0;
}
+static int sdebug_fail_cmd(struct scsi_cmnd *cmnd, int *retval,
+ struct sdebug_err_inject *info)
+{
+ struct scsi_device *sdp = cmnd->device;
+ struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
+ struct sdebug_err_inject *err;
+ unsigned char *cmd = cmnd->cmnd;
+ int ret = 0;
+ int result;
+
+ if (devip == NULL)
+ return 0;
+
+ list_for_each_entry(err, &devip->inject_err_list, list) {
+ if (err->type == ERR_FAIL_CMD &&
+ (err->cmd == cmd[0] || err->cmd == 0xff)) {
+ if (!err->cnt)
+ return 0;
+ ret = !!err->cnt;
+ goto out_handle;
+ }
+ }
+ return 0;
+
+out_handle:
+ if (err->cnt < 0)
+ err->cnt++;
+ mk_sense_buffer(cmnd, err->sense_key, err->asc, err->asq);
+ result = err->status_byte | err->host_byte << 16 | err->driver_byte << 24;
+ *info = *err;
+ *retval = schedule_resp(cmnd, devip, result, NULL, 0, 0);
+
+ return ret;
+}
+
static int scsi_debug_queuecommand(struct Scsi_Host *shost,
struct scsi_cmnd *scp)
{
@@ -7783,6 +7818,7 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
bool has_wlun_rl;
bool inject_now;
int ret = 0;
+ struct sdebug_err_inject err;
scsi_set_resid(scp, 0);
if (sdebug_statistics) {
@@ -7835,6 +7871,16 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
return ret;
}
+ if (sdebug_fail_cmd(scp, &ret, &err)) {
+ scmd_printk(KERN_INFO, scp,
+ "fail command 0x%x with hostbyte=0x%x, "
+ "driverbyte=0x%x, statusbyte=0x%x, "
+ "sense_key=0x%x, asc=0x%x, asq=0x%x\n",
+ opcode, err.host_byte, err.driver_byte,
+ err.status_byte, err.sense_key, err.asc, err.asq);
+ return ret;
+ }
+
if (unlikely(inject_now && !atomic_read(&sdeb_inject_pending)))
atomic_set(&sdeb_inject_pending, 1);
--
2.35.3
