scsi: scsi_debug: Set command result and sense data if error is injected

If a fail command 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):

Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Wenchao Hao <haowenchao2@huawei.com>
Link: https://lore.kernel.org/r/20231010092051.608007-7-haowenchao2@huawei.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Wenchao Hao 2023-10-10 17:20:47 +08:00 committed by Martin K. Petersen
parent 33bccf55c2
commit 3359227432

View file

@ -7797,6 +7797,48 @@ 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;
rcu_read_lock();
list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
if (err->type == ERR_FAIL_CMD &&
(err->cmd == cmd[0] || err->cmd == 0xff)) {
if (!err->cnt) {
rcu_read_unlock();
return 0;
}
ret = !!err->cnt;
rcu_read_unlock();
goto out_handle;
}
}
rcu_read_unlock();
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)
{
@ -7817,6 +7859,7 @@ 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) {
@ -7869,6 +7912,16 @@ 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);