scsi: scsi_debug: every_nth triggered error injection

This patch simplifies, or at least makes more consistent, the way setting
the every_nth parameter injects errors. Here is a list of 'opts' flags and
in which cases they inject errors when abs(every_nth)%command_count == 0 is
reached:

  - OPT_RECOVERED_ERR: issued on READ(*)s, WRITE(*)s and
                       WRITE_SCATTEREDs
  - OPT_DIF_ERR:       issued on READ(*)s, WRITE(*)s and
                       WRITE_SCATTEREDs
  - OPT_DIX_ERR:       issued on READ(*)s, WRITE(*)s and
                       WRITE_SCATTEREDs
  - OPT_SHORT_TRANSFER: issued on READ(*)s
  - OPT_TRANSPORT_ERR: issued on all commands
  - OPT_CMD_ABORT:     issued on all commands

The other uses of every_nth were not modified.

Previously if, for example, OPT_SHORT_TRANSFER was armed then if
(abs(every_nth) % command_count == 0) occurred during a command that was
_not_ a READ, then no error injection occurred. This behaviour puzzled
several testers. Now a global "inject_pending" flag is set and the _next_
READ will get hit and that flag is cleared. OPT_RECOVERED_ERR, OPT_DIF_ERR
and OPT_DIX_ERR have similar behaviour. A downside of this is that there
might be a hang-over pending injection that gets triggered by a following
test.

Also expand the every_nth runtime parameter so that it can take hex value
(i.e. with a leading '0x') as well as a decimal value. Now both the 'opts'
and the 'every_nth' runtime parameters can take hexadecimal values.

Link: https://lore.kernel.org/r/20200712182927.72044-2-dgilbert@interlog.com
Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Douglas Gilbert 2020-07-12 14:29:26 -04:00 committed by Martin K. Petersen
parent c10fa55f5e
commit 3a90a63d02
1 changed files with 101 additions and 130 deletions

View File

@ -187,21 +187,8 @@ static const char *sdebug_version_date = "20200421";
SDEBUG_OPT_SHORT_TRANSFER | \
SDEBUG_OPT_HOST_BUSY | \
SDEBUG_OPT_CMD_ABORT)
/* When "every_nth" > 0 then modulo "every_nth" commands:
* - a missing response is simulated if SDEBUG_OPT_TIMEOUT is set
* - a RECOVERED_ERROR is simulated on successful read and write
* commands if SDEBUG_OPT_RECOVERED_ERR is set.
* - a TRANSPORT_ERROR is simulated on successful read and write
* commands if SDEBUG_OPT_TRANSPORT_ERR is set.
* - similarly for DIF_ERR, DIX_ERR, SHORT_TRANSFER, HOST_BUSY and
* CMD_ABORT
*
* When "every_nth" < 0 then after "- every_nth" commands the selected
* error will be injected. The error will be injected on every subsequent
* command until some other action occurs; for example, the user writing
* a new value (other than -1 or 1) to every_nth:
* echo 0 > /sys/bus/pseudo/drivers/scsi_debug/every_nth
*/
#define SDEBUG_OPT_RECOV_DIF_DIX (SDEBUG_OPT_RECOVERED_ERR | \
SDEBUG_OPT_DIF_ERR | SDEBUG_OPT_DIX_ERR)
/* As indicated in SAM-5 and SPC-4 Unit Attentions (UAs) are returned in
* priority order. In the subset implemented here lower numbers have higher
@ -358,13 +345,6 @@ struct sdebug_queued_cmd {
*/
struct sdebug_defer *sd_dp;
struct scsi_cmnd *a_cmnd;
unsigned int inj_recovered:1;
unsigned int inj_transport:1;
unsigned int inj_dif:1;
unsigned int inj_dix:1;
unsigned int inj_short:1;
unsigned int inj_host_busy:1;
unsigned int inj_cmd_abort:1;
};
struct sdebug_queue {
@ -378,6 +358,7 @@ static atomic_t sdebug_cmnd_count; /* number of incoming commands */
static atomic_t sdebug_completions; /* count of deferred completions */
static atomic_t sdebug_miss_cpus; /* submission + completion cpus differ */
static atomic_t sdebug_a_tsf; /* 'almost task set full' counter */
static atomic_t sdeb_inject_pending;
struct opcode_info_t {
u8 num_attached; /* 0 if this is it (i.e. a leaf); use 0xff */
@ -3111,7 +3092,6 @@ static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
struct sdeb_store_info *sip = devip2sip(devip, true);
rwlock_t *macc_lckp = sip ? &sip->macc_lck : &sdeb_fake_rw_lck;
u8 *cmd = scp->cmnd;
struct sdebug_queued_cmd *sqcp;
switch (cmd[0]) {
case READ_16:
@ -3164,15 +3144,11 @@ static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
sdev_printk(KERN_ERR, scp->device, "Unprotected RD "
"to DIF device\n");
}
if (unlikely(sdebug_any_injecting_opt)) {
sqcp = (struct sdebug_queued_cmd *)scp->host_scribble;
if (sqcp) {
if (sqcp->inj_short)
num /= 2;
}
} else
sqcp = NULL;
if (unlikely((sdebug_opts & SDEBUG_OPT_SHORT_TRANSFER) &&
atomic_read(&sdeb_inject_pending))) {
num /= 2;
atomic_set(&sdeb_inject_pending, 0);
}
ret = check_device_access_params(scp, lba, num, false);
if (ret)
@ -3213,21 +3189,20 @@ static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
scsi_set_resid(scp, scsi_bufflen(scp) - ret);
if (unlikely(sqcp)) {
if (sqcp->inj_recovered) {
mk_sense_buffer(scp, RECOVERED_ERROR,
THRESHOLD_EXCEEDED, 0);
if (unlikely((sdebug_opts & SDEBUG_OPT_RECOV_DIF_DIX) &&
atomic_read(&sdeb_inject_pending))) {
if (sdebug_opts & SDEBUG_OPT_RECOVERED_ERR) {
mk_sense_buffer(scp, RECOVERED_ERROR, THRESHOLD_EXCEEDED, 0);
atomic_set(&sdeb_inject_pending, 0);
return check_condition_result;
} else if (sqcp->inj_transport) {
mk_sense_buffer(scp, ABORTED_COMMAND,
TRANSPORT_PROBLEM, ACK_NAK_TO);
return check_condition_result;
} else if (sqcp->inj_dif) {
} else if (sdebug_opts & SDEBUG_OPT_DIF_ERR) {
/* Logical block guard check failed */
mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
atomic_set(&sdeb_inject_pending, 0);
return illegal_condition_result;
} else if (sqcp->inj_dix) {
} else if (SDEBUG_OPT_DIX_ERR & sdebug_opts) {
mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
atomic_set(&sdeb_inject_pending, 0);
return illegal_condition_result;
}
}
@ -3506,23 +3481,21 @@ static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
"%s: write: cdb indicated=%u, IO sent=%d bytes\n",
my_name, num * sdebug_sector_size, ret);
if (unlikely(sdebug_any_injecting_opt)) {
struct sdebug_queued_cmd *sqcp =
(struct sdebug_queued_cmd *)scp->host_scribble;
if (sqcp) {
if (sqcp->inj_recovered) {
mk_sense_buffer(scp, RECOVERED_ERROR,
THRESHOLD_EXCEEDED, 0);
return check_condition_result;
} else if (sqcp->inj_dif) {
/* Logical block guard check failed */
mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
return illegal_condition_result;
} else if (sqcp->inj_dix) {
mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
return illegal_condition_result;
}
if (unlikely((sdebug_opts & SDEBUG_OPT_RECOV_DIF_DIX) &&
atomic_read(&sdeb_inject_pending))) {
if (sdebug_opts & SDEBUG_OPT_RECOVERED_ERR) {
mk_sense_buffer(scp, RECOVERED_ERROR, THRESHOLD_EXCEEDED, 0);
atomic_set(&sdeb_inject_pending, 0);
return check_condition_result;
} else if (sdebug_opts & SDEBUG_OPT_DIF_ERR) {
/* Logical block guard check failed */
mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
atomic_set(&sdeb_inject_pending, 0);
return illegal_condition_result;
} else if (sdebug_opts & SDEBUG_OPT_DIX_ERR) {
mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
atomic_set(&sdeb_inject_pending, 0);
return illegal_condition_result;
}
}
return 0;
@ -3664,28 +3637,24 @@ static int resp_write_scat(struct scsi_cmnd *scp,
"%s: write: cdb indicated=%u, IO sent=%d bytes\n",
my_name, num_by, ret);
if (unlikely(sdebug_any_injecting_opt)) {
struct sdebug_queued_cmd *sqcp =
(struct sdebug_queued_cmd *)scp->host_scribble;
if (sqcp) {
if (sqcp->inj_recovered) {
mk_sense_buffer(scp, RECOVERED_ERROR,
THRESHOLD_EXCEEDED, 0);
ret = illegal_condition_result;
goto err_out_unlock;
} else if (sqcp->inj_dif) {
/* Logical block guard check failed */
mk_sense_buffer(scp, ABORTED_COMMAND,
0x10, 1);
ret = illegal_condition_result;
goto err_out_unlock;
} else if (sqcp->inj_dix) {
mk_sense_buffer(scp, ILLEGAL_REQUEST,
0x10, 1);
ret = illegal_condition_result;
goto err_out_unlock;
}
if (unlikely((sdebug_opts & SDEBUG_OPT_RECOV_DIF_DIX) &&
atomic_read(&sdeb_inject_pending))) {
if (sdebug_opts & SDEBUG_OPT_RECOVERED_ERR) {
mk_sense_buffer(scp, RECOVERED_ERROR, THRESHOLD_EXCEEDED, 0);
atomic_set(&sdeb_inject_pending, 0);
ret = check_condition_result;
goto err_out_unlock;
} else if (sdebug_opts & SDEBUG_OPT_DIF_ERR) {
/* Logical block guard check failed */
mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
atomic_set(&sdeb_inject_pending, 0);
ret = illegal_condition_result;
goto err_out_unlock;
} else if (sdebug_opts & SDEBUG_OPT_DIX_ERR) {
mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
atomic_set(&sdeb_inject_pending, 0);
ret = illegal_condition_result;
goto err_out_unlock;
}
}
sg_off += num_by;
@ -5348,24 +5317,11 @@ static void clear_queue_stats(void)
atomic_set(&sdebug_a_tsf, 0);
}
static void setup_inject(struct sdebug_queue *sqp,
struct sdebug_queued_cmd *sqcp)
static bool inject_on_this_cmd(void)
{
if ((atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth)) > 0) {
if (sdebug_every_nth > 0)
sqcp->inj_recovered = sqcp->inj_transport
= sqcp->inj_dif
= sqcp->inj_dix = sqcp->inj_short
= sqcp->inj_host_busy = sqcp->inj_cmd_abort = 0;
return;
}
sqcp->inj_recovered = !!(SDEBUG_OPT_RECOVERED_ERR & sdebug_opts);
sqcp->inj_transport = !!(SDEBUG_OPT_TRANSPORT_ERR & sdebug_opts);
sqcp->inj_dif = !!(SDEBUG_OPT_DIF_ERR & sdebug_opts);
sqcp->inj_dix = !!(SDEBUG_OPT_DIX_ERR & sdebug_opts);
sqcp->inj_short = !!(SDEBUG_OPT_SHORT_TRANSFER & sdebug_opts);
sqcp->inj_host_busy = !!(SDEBUG_OPT_HOST_BUSY & sdebug_opts);
sqcp->inj_cmd_abort = !!(SDEBUG_OPT_CMD_ABORT & sdebug_opts);
if (sdebug_every_nth == 0)
return false;
return (atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth)) == 0;
}
#define INCLUSIVE_TIMING_MAX_NS 1000000 /* 1 millisecond */
@ -5382,7 +5338,8 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
int delta_jiff, int ndelay)
{
bool new_sd_dp;
int k, num_in_q, qdepth, inject;
bool inject = false;
int k, num_in_q, qdepth;
unsigned long iflags;
u64 ns_from_boot = 0;
struct sdebug_queue *sqp;
@ -5408,7 +5365,6 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
}
num_in_q = atomic_read(&devip->num_in_q);
qdepth = cmnd->device->queue_depth;
inject = 0;
if (unlikely((qdepth > 0) && (num_in_q >= qdepth))) {
if (scsi_result) {
spin_unlock_irqrestore(&sqp->qc_lock, iflags);
@ -5422,7 +5378,7 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
(atomic_inc_return(&sdebug_a_tsf) >=
abs(sdebug_every_nth))) {
atomic_set(&sdebug_a_tsf, 0);
inject = 1;
inject = true;
scsi_result = device_qfull_result;
}
}
@ -5452,8 +5408,6 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
cmnd->host_scribble = (unsigned char *)sqcp;
sd_dp = sqcp->sd_dp;
spin_unlock_irqrestore(&sqp->qc_lock, iflags);
if (unlikely(sdebug_every_nth && sdebug_any_injecting_opt))
setup_inject(sqp, sqcp);
if (!sd_dp) {
sd_dp = kzalloc(sizeof(*sd_dp), GFP_ATOMIC);
if (!sd_dp) {
@ -5474,13 +5428,20 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
ns_from_boot = ktime_get_boottime_ns();
/* one of the resp_*() response functions is called here */
cmnd->result = pfp != NULL ? pfp(cmnd, devip) : 0;
cmnd->result = pfp ? pfp(cmnd, devip) : 0;
if (cmnd->result & SDEG_RES_IMMED_MASK) {
cmnd->result &= ~SDEG_RES_IMMED_MASK;
delta_jiff = ndelay = 0;
}
if (cmnd->result == 0 && scsi_result != 0)
cmnd->result = scsi_result;
if (cmnd->result == 0 && unlikely(sdebug_opts & SDEBUG_OPT_TRANSPORT_ERR)) {
if (atomic_read(&sdeb_inject_pending)) {
mk_sense_buffer(cmnd, ABORTED_COMMAND, TRANSPORT_PROBLEM, ACK_NAK_TO);
atomic_set(&sdeb_inject_pending, 0);
cmnd->result = check_condition_result;
}
}
if (unlikely(sdebug_verbose && cmnd->result))
sdev_printk(KERN_INFO, sdp, "%s: non-zero result=0x%x\n",
@ -5546,21 +5507,20 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
if (sdebug_statistics)
sd_dp->issuing_cpu = raw_smp_processor_id();
sd_dp->defer_t = SDEB_DEFER_WQ;
if (unlikely(sqcp->inj_cmd_abort))
if (unlikely((sdebug_opts & SDEBUG_OPT_CMD_ABORT) &&
atomic_read(&sdeb_inject_pending)))
sd_dp->aborted = true;
schedule_work(&sd_dp->ew.work);
if (unlikely(sqcp->inj_cmd_abort)) {
sdev_printk(KERN_INFO, sdp, "abort request tag %d\n",
cmnd->request->tag);
if (unlikely((sdebug_opts & SDEBUG_OPT_CMD_ABORT) &&
atomic_read(&sdeb_inject_pending))) {
sdev_printk(KERN_INFO, sdp, "abort request tag %d\n", cmnd->request->tag);
blk_abort_request(cmnd->request);
atomic_set(&sdeb_inject_pending, 0);
}
}
if (unlikely((SDEBUG_OPT_Q_NOISE & sdebug_opts) &&
(scsi_result == device_qfull_result)))
sdev_printk(KERN_INFO, sdp,
"%s: num_in_q=%d +1, %s%s\n", __func__,
num_in_q, (inject ? "<inject> " : ""),
"status: TASK SET FULL");
if (unlikely((SDEBUG_OPT_Q_NOISE & sdebug_opts) && scsi_result == device_qfull_result))
sdev_printk(KERN_INFO, sdp, "%s: num_in_q=%d +1, %s%s\n", __func__,
num_in_q, (inject ? "<inject> " : ""), "status: TASK SET FULL");
return 0;
respond_in_thread: /* call back to mid-layer using invocation thread */
@ -6097,17 +6057,27 @@ static ssize_t every_nth_store(struct device_driver *ddp, const char *buf,
size_t count)
{
int nth;
char work[20];
if ((count > 0) && (1 == sscanf(buf, "%d", &nth))) {
sdebug_every_nth = nth;
if (nth && !sdebug_statistics) {
pr_info("every_nth needs statistics=1, set it\n");
sdebug_statistics = true;
if (sscanf(buf, "%10s", work) == 1) {
if (strncasecmp(work, "0x", 2) == 0) {
if (kstrtoint(work + 2, 16, &nth) == 0)
goto every_nth_done;
} else {
if (kstrtoint(work, 10, &nth) == 0)
goto every_nth_done;
}
tweak_cmnd_count();
return count;
}
return -EINVAL;
every_nth_done:
sdebug_every_nth = nth;
if (nth && !sdebug_statistics) {
pr_info("every_nth needs statistics=1, set it\n");
sdebug_statistics = true;
}
tweak_cmnd_count();
return count;
}
static DRIVER_ATTR_RW(every_nth);
@ -7102,12 +7072,6 @@ static bool fake_timeout(struct scsi_cmnd *scp)
return false;
}
static bool fake_host_busy(struct scsi_cmnd *scp)
{
return (sdebug_opts & SDEBUG_OPT_HOST_BUSY) &&
(atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth)) == 0;
}
static int scsi_debug_queuecommand(struct Scsi_Host *shost,
struct scsi_cmnd *scp)
{
@ -7116,7 +7080,6 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
const struct opcode_info_t *oip;
const struct opcode_info_t *r_oip;
struct sdebug_dev_info *devip;
u8 *cmd = scp->cmnd;
int (*r_pfp)(struct scsi_cmnd *, struct sdebug_dev_info *);
int (*pfp)(struct scsi_cmnd *, struct sdebug_dev_info *) = NULL;
@ -7126,10 +7089,15 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
u16 sa;
u8 opcode = cmd[0];
bool has_wlun_rl;
bool inject_now;
scsi_set_resid(scp, 0);
if (sdebug_statistics)
if (sdebug_statistics) {
atomic_inc(&sdebug_cmnd_count);
inject_now = inject_on_this_cmd();
} else {
inject_now = false;
}
if (unlikely(sdebug_verbose &&
!(SDEBUG_OPT_NO_CDB_NOISE & sdebug_opts))) {
char b[120];
@ -7147,7 +7115,7 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
sdev_printk(KERN_INFO, sdp, "%s: tag=%#x, cmd %s\n", my_name,
blk_mq_unique_tag(scp->request), b);
}
if (fake_host_busy(scp))
if (unlikely(inject_now && (sdebug_opts & SDEBUG_OPT_HOST_BUSY)))
return SCSI_MLQUEUE_HOST_BUSY;
has_wlun_rl = (sdp->lun == SCSI_W_LUN_REPORT_LUNS);
if (unlikely((sdp->lun >= sdebug_max_luns) && !has_wlun_rl))
@ -7161,6 +7129,9 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
if (NULL == devip)
goto err_out;
}
if (unlikely(inject_now && !atomic_read(&sdeb_inject_pending)))
atomic_set(&sdeb_inject_pending, 1);
na = oip->num_attached;
r_pfp = oip->pfp;
if (na) { /* multiple commands with this opcode */