From 3a90a63d02b8b7e8348d7549f55d24e1bb3a293f Mon Sep 17 00:00:00 2001 From: Douglas Gilbert Date: Sun, 12 Jul 2020 14:29:26 -0400 Subject: [PATCH] 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 Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_debug.c | 231 ++++++++++++++++++++-------------------------- 1 file changed, 101 insertions(+), 130 deletions(-) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 802ccd3..5eec23a 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -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); - return check_condition_result; - } else if (sqcp->inj_transport) { - mk_sense_buffer(scp, ABORTED_COMMAND, - TRANSPORT_PROBLEM, ACK_NAK_TO); + 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_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 ? " " : ""), - "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 ? " " : ""), "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 */ -- 2.7.4