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- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * scsi_error.c Copyright (C) 1997 Eric Youngdale
- *
- * SCSI error/timeout handling
- * Initial versions: Eric Youngdale. Based upon conversations with
- * Leonard Zubkoff and David Miller at Linux Expo,
- * ideas originating from all over the place.
- *
- * Restructured scsi_unjam_host and associated functions.
- * September 04, 2002 Mike Anderson ([email protected])
- *
- * Forward port of Russell King's ([email protected]) changes and
- * minor cleanups.
- * September 30, 2002 Mike Anderson ([email protected])
- */
- #include <linux/module.h>
- #include <linux/sched.h>
- #include <linux/gfp.h>
- #include <linux/timer.h>
- #include <linux/string.h>
- #include <linux/kernel.h>
- #include <linux/freezer.h>
- #include <linux/kthread.h>
- #include <linux/interrupt.h>
- #include <linux/blkdev.h>
- #include <linux/delay.h>
- #include <linux/jiffies.h>
- #include <scsi/scsi.h>
- #include <scsi/scsi_cmnd.h>
- #include <scsi/scsi_dbg.h>
- #include <scsi/scsi_device.h>
- #include <scsi/scsi_driver.h>
- #include <scsi/scsi_eh.h>
- #include <scsi/scsi_common.h>
- #include <scsi/scsi_transport.h>
- #include <scsi/scsi_host.h>
- #include <scsi/scsi_ioctl.h>
- #include <scsi/scsi_dh.h>
- #include <scsi/scsi_devinfo.h>
- #include <scsi/sg.h>
- #include "scsi_priv.h"
- #include "scsi_logging.h"
- #include "scsi_transport_api.h"
- #include <trace/events/scsi.h>
- #include <asm/unaligned.h>
- /*
- * These should *probably* be handled by the host itself.
- * Since it is allowed to sleep, it probably should.
- */
- #define BUS_RESET_SETTLE_TIME (10)
- #define HOST_RESET_SETTLE_TIME (10)
- static int scsi_eh_try_stu(struct scsi_cmnd *scmd);
- static enum scsi_disposition scsi_try_to_abort_cmd(struct scsi_host_template *,
- struct scsi_cmnd *);
- void scsi_eh_wakeup(struct Scsi_Host *shost)
- {
- lockdep_assert_held(shost->host_lock);
- if (scsi_host_busy(shost) == shost->host_failed) {
- trace_scsi_eh_wakeup(shost);
- wake_up_process(shost->ehandler);
- SCSI_LOG_ERROR_RECOVERY(5, shost_printk(KERN_INFO, shost,
- "Waking error handler thread\n"));
- }
- }
- /**
- * scsi_schedule_eh - schedule EH for SCSI host
- * @shost: SCSI host to invoke error handling on.
- *
- * Schedule SCSI EH without scmd.
- */
- void scsi_schedule_eh(struct Scsi_Host *shost)
- {
- unsigned long flags;
- spin_lock_irqsave(shost->host_lock, flags);
- if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 ||
- scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) {
- shost->host_eh_scheduled++;
- scsi_eh_wakeup(shost);
- }
- spin_unlock_irqrestore(shost->host_lock, flags);
- }
- EXPORT_SYMBOL_GPL(scsi_schedule_eh);
- static int scsi_host_eh_past_deadline(struct Scsi_Host *shost)
- {
- if (!shost->last_reset || shost->eh_deadline == -1)
- return 0;
- /*
- * 32bit accesses are guaranteed to be atomic
- * (on all supported architectures), so instead
- * of using a spinlock we can as well double check
- * if eh_deadline has been set to 'off' during the
- * time_before call.
- */
- if (time_before(jiffies, shost->last_reset + shost->eh_deadline) &&
- shost->eh_deadline > -1)
- return 0;
- return 1;
- }
- static bool scsi_cmd_retry_allowed(struct scsi_cmnd *cmd)
- {
- if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
- return true;
- return ++cmd->retries <= cmd->allowed;
- }
- static bool scsi_eh_should_retry_cmd(struct scsi_cmnd *cmd)
- {
- struct scsi_device *sdev = cmd->device;
- struct Scsi_Host *host = sdev->host;
- if (host->hostt->eh_should_retry_cmd)
- return host->hostt->eh_should_retry_cmd(cmd);
- return true;
- }
- /**
- * scmd_eh_abort_handler - Handle command aborts
- * @work: command to be aborted.
- *
- * Note: this function must be called only for a command that has timed out.
- * Because the block layer marks a request as complete before it calls
- * scsi_timeout(), a .scsi_done() call from the LLD for a command that has
- * timed out do not have any effect. Hence it is safe to call
- * scsi_finish_command() from this function.
- */
- void
- scmd_eh_abort_handler(struct work_struct *work)
- {
- struct scsi_cmnd *scmd =
- container_of(work, struct scsi_cmnd, abort_work.work);
- struct scsi_device *sdev = scmd->device;
- struct Scsi_Host *shost = sdev->host;
- enum scsi_disposition rtn;
- unsigned long flags;
- if (scsi_host_eh_past_deadline(shost)) {
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "eh timeout, not aborting\n"));
- goto out;
- }
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "aborting command\n"));
- rtn = scsi_try_to_abort_cmd(shost->hostt, scmd);
- if (rtn != SUCCESS) {
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "cmd abort %s\n",
- (rtn == FAST_IO_FAIL) ?
- "not send" : "failed"));
- goto out;
- }
- set_host_byte(scmd, DID_TIME_OUT);
- if (scsi_host_eh_past_deadline(shost)) {
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "eh timeout, not retrying "
- "aborted command\n"));
- goto out;
- }
- spin_lock_irqsave(shost->host_lock, flags);
- list_del_init(&scmd->eh_entry);
- /*
- * If the abort succeeds, and there is no further
- * EH action, clear the ->last_reset time.
- */
- if (list_empty(&shost->eh_abort_list) &&
- list_empty(&shost->eh_cmd_q))
- if (shost->eh_deadline != -1)
- shost->last_reset = 0;
- spin_unlock_irqrestore(shost->host_lock, flags);
- if (!scsi_noretry_cmd(scmd) &&
- scsi_cmd_retry_allowed(scmd) &&
- scsi_eh_should_retry_cmd(scmd)) {
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_WARNING, scmd,
- "retry aborted command\n"));
- scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
- } else {
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_WARNING, scmd,
- "finish aborted command\n"));
- scsi_finish_command(scmd);
- }
- return;
- out:
- spin_lock_irqsave(shost->host_lock, flags);
- list_del_init(&scmd->eh_entry);
- spin_unlock_irqrestore(shost->host_lock, flags);
- scsi_eh_scmd_add(scmd);
- }
- /**
- * scsi_abort_command - schedule a command abort
- * @scmd: scmd to abort.
- *
- * We only need to abort commands after a command timeout
- */
- static int
- scsi_abort_command(struct scsi_cmnd *scmd)
- {
- struct scsi_device *sdev = scmd->device;
- struct Scsi_Host *shost = sdev->host;
- unsigned long flags;
- if (!shost->hostt->eh_abort_handler) {
- /* No abort handler, fail command directly */
- return FAILED;
- }
- if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
- /*
- * Retry after abort failed, escalate to next level.
- */
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "previous abort failed\n"));
- BUG_ON(delayed_work_pending(&scmd->abort_work));
- return FAILED;
- }
- spin_lock_irqsave(shost->host_lock, flags);
- if (shost->eh_deadline != -1 && !shost->last_reset)
- shost->last_reset = jiffies;
- BUG_ON(!list_empty(&scmd->eh_entry));
- list_add_tail(&scmd->eh_entry, &shost->eh_abort_list);
- spin_unlock_irqrestore(shost->host_lock, flags);
- scmd->eh_eflags |= SCSI_EH_ABORT_SCHEDULED;
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd, "abort scheduled\n"));
- queue_delayed_work(shost->tmf_work_q, &scmd->abort_work, HZ / 100);
- return SUCCESS;
- }
- /**
- * scsi_eh_reset - call into ->eh_action to reset internal counters
- * @scmd: scmd to run eh on.
- *
- * The scsi driver might be carrying internal state about the
- * devices, so we need to call into the driver to reset the
- * internal state once the error handler is started.
- */
- static void scsi_eh_reset(struct scsi_cmnd *scmd)
- {
- if (!blk_rq_is_passthrough(scsi_cmd_to_rq(scmd))) {
- struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
- if (sdrv->eh_reset)
- sdrv->eh_reset(scmd);
- }
- }
- static void scsi_eh_inc_host_failed(struct rcu_head *head)
- {
- struct scsi_cmnd *scmd = container_of(head, typeof(*scmd), rcu);
- struct Scsi_Host *shost = scmd->device->host;
- unsigned long flags;
- spin_lock_irqsave(shost->host_lock, flags);
- shost->host_failed++;
- scsi_eh_wakeup(shost);
- spin_unlock_irqrestore(shost->host_lock, flags);
- }
- /**
- * scsi_eh_scmd_add - add scsi cmd to error handling.
- * @scmd: scmd to run eh on.
- */
- void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
- {
- struct Scsi_Host *shost = scmd->device->host;
- unsigned long flags;
- int ret;
- WARN_ON_ONCE(!shost->ehandler);
- spin_lock_irqsave(shost->host_lock, flags);
- if (scsi_host_set_state(shost, SHOST_RECOVERY)) {
- ret = scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY);
- WARN_ON_ONCE(ret);
- }
- if (shost->eh_deadline != -1 && !shost->last_reset)
- shost->last_reset = jiffies;
- scsi_eh_reset(scmd);
- list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q);
- spin_unlock_irqrestore(shost->host_lock, flags);
- /*
- * Ensure that all tasks observe the host state change before the
- * host_failed change.
- */
- call_rcu_hurry(&scmd->rcu, scsi_eh_inc_host_failed);
- }
- /**
- * scsi_timeout - Timeout function for normal scsi commands.
- * @req: request that is timing out.
- *
- * Notes:
- * We do not need to lock this. There is the potential for a race
- * only in that the normal completion handling might run, but if the
- * normal completion function determines that the timer has already
- * fired, then it mustn't do anything.
- */
- enum blk_eh_timer_return scsi_timeout(struct request *req)
- {
- struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
- struct Scsi_Host *host = scmd->device->host;
- trace_scsi_dispatch_cmd_timeout(scmd);
- scsi_log_completion(scmd, TIMEOUT_ERROR);
- atomic_inc(&scmd->device->iotmo_cnt);
- if (host->eh_deadline != -1 && !host->last_reset)
- host->last_reset = jiffies;
- if (host->hostt->eh_timed_out) {
- switch (host->hostt->eh_timed_out(scmd)) {
- case SCSI_EH_DONE:
- return BLK_EH_DONE;
- case SCSI_EH_RESET_TIMER:
- return BLK_EH_RESET_TIMER;
- case SCSI_EH_NOT_HANDLED:
- break;
- }
- }
- /*
- * If scsi_done() has already set SCMD_STATE_COMPLETE, do not modify
- * *scmd.
- */
- if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))
- return BLK_EH_DONE;
- if (scsi_abort_command(scmd) != SUCCESS) {
- set_host_byte(scmd, DID_TIME_OUT);
- scsi_eh_scmd_add(scmd);
- }
- return BLK_EH_DONE;
- }
- /**
- * scsi_block_when_processing_errors - Prevent cmds from being queued.
- * @sdev: Device on which we are performing recovery.
- *
- * Description:
- * We block until the host is out of error recovery, and then check to
- * see whether the host or the device is offline.
- *
- * Return value:
- * 0 when dev was taken offline by error recovery. 1 OK to proceed.
- */
- int scsi_block_when_processing_errors(struct scsi_device *sdev)
- {
- int online;
- wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host));
- online = scsi_device_online(sdev);
- return online;
- }
- EXPORT_SYMBOL(scsi_block_when_processing_errors);
- #ifdef CONFIG_SCSI_LOGGING
- /**
- * scsi_eh_prt_fail_stats - Log info on failures.
- * @shost: scsi host being recovered.
- * @work_q: Queue of scsi cmds to process.
- */
- static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost,
- struct list_head *work_q)
- {
- struct scsi_cmnd *scmd;
- struct scsi_device *sdev;
- int total_failures = 0;
- int cmd_failed = 0;
- int cmd_cancel = 0;
- int devices_failed = 0;
- shost_for_each_device(sdev, shost) {
- list_for_each_entry(scmd, work_q, eh_entry) {
- if (scmd->device == sdev) {
- ++total_failures;
- if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED)
- ++cmd_cancel;
- else
- ++cmd_failed;
- }
- }
- if (cmd_cancel || cmd_failed) {
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: cmds failed: %d, cancel: %d\n",
- __func__, cmd_failed,
- cmd_cancel));
- cmd_cancel = 0;
- cmd_failed = 0;
- ++devices_failed;
- }
- }
- SCSI_LOG_ERROR_RECOVERY(2, shost_printk(KERN_INFO, shost,
- "Total of %d commands on %d"
- " devices require eh work\n",
- total_failures, devices_failed));
- }
- #endif
- /**
- * scsi_report_lun_change - Set flag on all *other* devices on the same target
- * to indicate that a UNIT ATTENTION is expected.
- * @sdev: Device reporting the UNIT ATTENTION
- */
- static void scsi_report_lun_change(struct scsi_device *sdev)
- {
- sdev->sdev_target->expecting_lun_change = 1;
- }
- /**
- * scsi_report_sense - Examine scsi sense information and log messages for
- * certain conditions, also issue uevents for some of them.
- * @sdev: Device reporting the sense code
- * @sshdr: sshdr to be examined
- */
- static void scsi_report_sense(struct scsi_device *sdev,
- struct scsi_sense_hdr *sshdr)
- {
- enum scsi_device_event evt_type = SDEV_EVT_MAXBITS; /* i.e. none */
- if (sshdr->sense_key == UNIT_ATTENTION) {
- if (sshdr->asc == 0x3f && sshdr->ascq == 0x03) {
- evt_type = SDEV_EVT_INQUIRY_CHANGE_REPORTED;
- sdev_printk(KERN_WARNING, sdev,
- "Inquiry data has changed");
- } else if (sshdr->asc == 0x3f && sshdr->ascq == 0x0e) {
- evt_type = SDEV_EVT_LUN_CHANGE_REPORTED;
- scsi_report_lun_change(sdev);
- sdev_printk(KERN_WARNING, sdev,
- "LUN assignments on this target have "
- "changed. The Linux SCSI layer does not "
- "automatically remap LUN assignments.\n");
- } else if (sshdr->asc == 0x3f)
- sdev_printk(KERN_WARNING, sdev,
- "Operating parameters on this target have "
- "changed. The Linux SCSI layer does not "
- "automatically adjust these parameters.\n");
- if (sshdr->asc == 0x38 && sshdr->ascq == 0x07) {
- evt_type = SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED;
- sdev_printk(KERN_WARNING, sdev,
- "Warning! Received an indication that the "
- "LUN reached a thin provisioning soft "
- "threshold.\n");
- }
- if (sshdr->asc == 0x29) {
- evt_type = SDEV_EVT_POWER_ON_RESET_OCCURRED;
- /*
- * Do not print message if it is an expected side-effect
- * of runtime PM.
- */
- if (!sdev->silence_suspend)
- sdev_printk(KERN_WARNING, sdev,
- "Power-on or device reset occurred\n");
- }
- if (sshdr->asc == 0x2a && sshdr->ascq == 0x01) {
- evt_type = SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED;
- sdev_printk(KERN_WARNING, sdev,
- "Mode parameters changed");
- } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x06) {
- evt_type = SDEV_EVT_ALUA_STATE_CHANGE_REPORTED;
- sdev_printk(KERN_WARNING, sdev,
- "Asymmetric access state changed");
- } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x09) {
- evt_type = SDEV_EVT_CAPACITY_CHANGE_REPORTED;
- sdev_printk(KERN_WARNING, sdev,
- "Capacity data has changed");
- } else if (sshdr->asc == 0x2a)
- sdev_printk(KERN_WARNING, sdev,
- "Parameters changed");
- }
- if (evt_type != SDEV_EVT_MAXBITS) {
- set_bit(evt_type, sdev->pending_events);
- schedule_work(&sdev->event_work);
- }
- }
- static inline void set_scsi_ml_byte(struct scsi_cmnd *cmd, u8 status)
- {
- cmd->result = (cmd->result & 0xffff00ff) | (status << 8);
- }
- /**
- * scsi_check_sense - Examine scsi cmd sense
- * @scmd: Cmd to have sense checked.
- *
- * Return value:
- * SUCCESS or FAILED or NEEDS_RETRY or ADD_TO_MLQUEUE
- *
- * Notes:
- * When a deferred error is detected the current command has
- * not been executed and needs retrying.
- */
- enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd)
- {
- struct scsi_device *sdev = scmd->device;
- struct scsi_sense_hdr sshdr;
- if (! scsi_command_normalize_sense(scmd, &sshdr))
- return FAILED; /* no valid sense data */
- scsi_report_sense(sdev, &sshdr);
- if (scsi_sense_is_deferred(&sshdr))
- return NEEDS_RETRY;
- if (sdev->handler && sdev->handler->check_sense) {
- enum scsi_disposition rc;
- rc = sdev->handler->check_sense(sdev, &sshdr);
- if (rc != SCSI_RETURN_NOT_HANDLED)
- return rc;
- /* handler does not care. Drop down to default handling */
- }
- if (scmd->cmnd[0] == TEST_UNIT_READY &&
- scmd->submitter != SUBMITTED_BY_SCSI_ERROR_HANDLER)
- /*
- * nasty: for mid-layer issued TURs, we need to return the
- * actual sense data without any recovery attempt. For eh
- * issued ones, we need to try to recover and interpret
- */
- return SUCCESS;
- /*
- * Previous logic looked for FILEMARK, EOM or ILI which are
- * mainly associated with tapes and returned SUCCESS.
- */
- if (sshdr.response_code == 0x70) {
- /* fixed format */
- if (scmd->sense_buffer[2] & 0xe0)
- return SUCCESS;
- } else {
- /*
- * descriptor format: look for "stream commands sense data
- * descriptor" (see SSC-3). Assume single sense data
- * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
- */
- if ((sshdr.additional_length > 3) &&
- (scmd->sense_buffer[8] == 0x4) &&
- (scmd->sense_buffer[11] & 0xe0))
- return SUCCESS;
- }
- switch (sshdr.sense_key) {
- case NO_SENSE:
- return SUCCESS;
- case RECOVERED_ERROR:
- return /* soft_error */ SUCCESS;
- case ABORTED_COMMAND:
- if (sshdr.asc == 0x10) /* DIF */
- return SUCCESS;
- if (sshdr.asc == 0x44 && sdev->sdev_bflags & BLIST_RETRY_ITF)
- return ADD_TO_MLQUEUE;
- if (sshdr.asc == 0xc1 && sshdr.ascq == 0x01 &&
- sdev->sdev_bflags & BLIST_RETRY_ASC_C1)
- return ADD_TO_MLQUEUE;
- return NEEDS_RETRY;
- case NOT_READY:
- case UNIT_ATTENTION:
- /*
- * if we are expecting a cc/ua because of a bus reset that we
- * performed, treat this just as a retry. otherwise this is
- * information that we should pass up to the upper-level driver
- * so that we can deal with it there.
- */
- if (scmd->device->expecting_cc_ua) {
- /*
- * Because some device does not queue unit
- * attentions correctly, we carefully check
- * additional sense code and qualifier so as
- * not to squash media change unit attention.
- */
- if (sshdr.asc != 0x28 || sshdr.ascq != 0x00) {
- scmd->device->expecting_cc_ua = 0;
- return NEEDS_RETRY;
- }
- }
- /*
- * we might also expect a cc/ua if another LUN on the target
- * reported a UA with an ASC/ASCQ of 3F 0E -
- * REPORTED LUNS DATA HAS CHANGED.
- */
- if (scmd->device->sdev_target->expecting_lun_change &&
- sshdr.asc == 0x3f && sshdr.ascq == 0x0e)
- return NEEDS_RETRY;
- /*
- * if the device is in the process of becoming ready, we
- * should retry.
- */
- if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01))
- return NEEDS_RETRY;
- /*
- * if the device is not started, we need to wake
- * the error handler to start the motor
- */
- if (scmd->device->allow_restart &&
- (sshdr.asc == 0x04) && (sshdr.ascq == 0x02))
- return FAILED;
- /*
- * Pass the UA upwards for a determination in the completion
- * functions.
- */
- return SUCCESS;
- /* these are not supported */
- case DATA_PROTECT:
- if (sshdr.asc == 0x27 && sshdr.ascq == 0x07) {
- /* Thin provisioning hard threshold reached */
- set_scsi_ml_byte(scmd, SCSIML_STAT_NOSPC);
- return SUCCESS;
- }
- fallthrough;
- case COPY_ABORTED:
- case VOLUME_OVERFLOW:
- case MISCOMPARE:
- case BLANK_CHECK:
- set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE);
- return SUCCESS;
- case MEDIUM_ERROR:
- if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */
- sshdr.asc == 0x13 || /* AMNF DATA FIELD */
- sshdr.asc == 0x14) { /* RECORD NOT FOUND */
- set_scsi_ml_byte(scmd, SCSIML_STAT_MED_ERROR);
- return SUCCESS;
- }
- return NEEDS_RETRY;
- case HARDWARE_ERROR:
- if (scmd->device->retry_hwerror)
- return ADD_TO_MLQUEUE;
- else
- set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE);
- fallthrough;
- case ILLEGAL_REQUEST:
- if (sshdr.asc == 0x20 || /* Invalid command operation code */
- sshdr.asc == 0x21 || /* Logical block address out of range */
- sshdr.asc == 0x22 || /* Invalid function */
- sshdr.asc == 0x24 || /* Invalid field in cdb */
- sshdr.asc == 0x26 || /* Parameter value invalid */
- sshdr.asc == 0x27) { /* Write protected */
- set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE);
- }
- return SUCCESS;
- default:
- return SUCCESS;
- }
- }
- EXPORT_SYMBOL_GPL(scsi_check_sense);
- static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
- {
- struct scsi_host_template *sht = sdev->host->hostt;
- struct scsi_device *tmp_sdev;
- if (!sht->track_queue_depth ||
- sdev->queue_depth >= sdev->max_queue_depth)
- return;
- if (time_before(jiffies,
- sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
- return;
- if (time_before(jiffies,
- sdev->last_queue_full_time + sdev->queue_ramp_up_period))
- return;
- /*
- * Walk all devices of a target and do
- * ramp up on them.
- */
- shost_for_each_device(tmp_sdev, sdev->host) {
- if (tmp_sdev->channel != sdev->channel ||
- tmp_sdev->id != sdev->id ||
- tmp_sdev->queue_depth == sdev->max_queue_depth)
- continue;
- scsi_change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1);
- sdev->last_queue_ramp_up = jiffies;
- }
- }
- static void scsi_handle_queue_full(struct scsi_device *sdev)
- {
- struct scsi_host_template *sht = sdev->host->hostt;
- struct scsi_device *tmp_sdev;
- if (!sht->track_queue_depth)
- return;
- shost_for_each_device(tmp_sdev, sdev->host) {
- if (tmp_sdev->channel != sdev->channel ||
- tmp_sdev->id != sdev->id)
- continue;
- /*
- * We do not know the number of commands that were at
- * the device when we got the queue full so we start
- * from the highest possible value and work our way down.
- */
- scsi_track_queue_full(tmp_sdev, tmp_sdev->queue_depth - 1);
- }
- }
- /**
- * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
- * @scmd: SCSI cmd to examine.
- *
- * Notes:
- * This is *only* called when we are examining the status of commands
- * queued during error recovery. the main difference here is that we
- * don't allow for the possibility of retries here, and we are a lot
- * more restrictive about what we consider acceptable.
- */
- static enum scsi_disposition scsi_eh_completed_normally(struct scsi_cmnd *scmd)
- {
- /*
- * first check the host byte, to see if there is anything in there
- * that would indicate what we need to do.
- */
- if (host_byte(scmd->result) == DID_RESET) {
- /*
- * rats. we are already in the error handler, so we now
- * get to try and figure out what to do next. if the sense
- * is valid, we have a pretty good idea of what to do.
- * if not, we mark it as FAILED.
- */
- return scsi_check_sense(scmd);
- }
- if (host_byte(scmd->result) != DID_OK)
- return FAILED;
- /*
- * now, check the status byte to see if this indicates
- * anything special.
- */
- switch (get_status_byte(scmd)) {
- case SAM_STAT_GOOD:
- scsi_handle_queue_ramp_up(scmd->device);
- fallthrough;
- case SAM_STAT_COMMAND_TERMINATED:
- return SUCCESS;
- case SAM_STAT_CHECK_CONDITION:
- return scsi_check_sense(scmd);
- case SAM_STAT_CONDITION_MET:
- case SAM_STAT_INTERMEDIATE:
- case SAM_STAT_INTERMEDIATE_CONDITION_MET:
- /*
- * who knows? FIXME(eric)
- */
- return SUCCESS;
- case SAM_STAT_RESERVATION_CONFLICT:
- if (scmd->cmnd[0] == TEST_UNIT_READY)
- /* it is a success, we probed the device and
- * found it */
- return SUCCESS;
- /* otherwise, we failed to send the command */
- return FAILED;
- case SAM_STAT_TASK_SET_FULL:
- scsi_handle_queue_full(scmd->device);
- fallthrough;
- case SAM_STAT_BUSY:
- return NEEDS_RETRY;
- default:
- return FAILED;
- }
- return FAILED;
- }
- /**
- * scsi_eh_done - Completion function for error handling.
- * @scmd: Cmd that is done.
- */
- void scsi_eh_done(struct scsi_cmnd *scmd)
- {
- struct completion *eh_action;
- SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
- "%s result: %x\n", __func__, scmd->result));
- eh_action = scmd->device->host->eh_action;
- if (eh_action)
- complete(eh_action);
- }
- /**
- * scsi_try_host_reset - ask host adapter to reset itself
- * @scmd: SCSI cmd to send host reset.
- */
- static enum scsi_disposition scsi_try_host_reset(struct scsi_cmnd *scmd)
- {
- unsigned long flags;
- enum scsi_disposition rtn;
- struct Scsi_Host *host = scmd->device->host;
- struct scsi_host_template *hostt = host->hostt;
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, host, "Snd Host RST\n"));
- if (!hostt->eh_host_reset_handler)
- return FAILED;
- rtn = hostt->eh_host_reset_handler(scmd);
- if (rtn == SUCCESS) {
- if (!hostt->skip_settle_delay)
- ssleep(HOST_RESET_SETTLE_TIME);
- spin_lock_irqsave(host->host_lock, flags);
- scsi_report_bus_reset(host, scmd_channel(scmd));
- spin_unlock_irqrestore(host->host_lock, flags);
- }
- return rtn;
- }
- /**
- * scsi_try_bus_reset - ask host to perform a bus reset
- * @scmd: SCSI cmd to send bus reset.
- */
- static enum scsi_disposition scsi_try_bus_reset(struct scsi_cmnd *scmd)
- {
- unsigned long flags;
- enum scsi_disposition rtn;
- struct Scsi_Host *host = scmd->device->host;
- struct scsi_host_template *hostt = host->hostt;
- SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
- "%s: Snd Bus RST\n", __func__));
- if (!hostt->eh_bus_reset_handler)
- return FAILED;
- rtn = hostt->eh_bus_reset_handler(scmd);
- if (rtn == SUCCESS) {
- if (!hostt->skip_settle_delay)
- ssleep(BUS_RESET_SETTLE_TIME);
- spin_lock_irqsave(host->host_lock, flags);
- scsi_report_bus_reset(host, scmd_channel(scmd));
- spin_unlock_irqrestore(host->host_lock, flags);
- }
- return rtn;
- }
- static void __scsi_report_device_reset(struct scsi_device *sdev, void *data)
- {
- sdev->was_reset = 1;
- sdev->expecting_cc_ua = 1;
- }
- /**
- * scsi_try_target_reset - Ask host to perform a target reset
- * @scmd: SCSI cmd used to send a target reset
- *
- * Notes:
- * There is no timeout for this operation. if this operation is
- * unreliable for a given host, then the host itself needs to put a
- * timer on it, and set the host back to a consistent state prior to
- * returning.
- */
- static enum scsi_disposition scsi_try_target_reset(struct scsi_cmnd *scmd)
- {
- unsigned long flags;
- enum scsi_disposition rtn;
- struct Scsi_Host *host = scmd->device->host;
- struct scsi_host_template *hostt = host->hostt;
- if (!hostt->eh_target_reset_handler)
- return FAILED;
- rtn = hostt->eh_target_reset_handler(scmd);
- if (rtn == SUCCESS) {
- spin_lock_irqsave(host->host_lock, flags);
- __starget_for_each_device(scsi_target(scmd->device), NULL,
- __scsi_report_device_reset);
- spin_unlock_irqrestore(host->host_lock, flags);
- }
- return rtn;
- }
- /**
- * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
- * @scmd: SCSI cmd used to send BDR
- *
- * Notes:
- * There is no timeout for this operation. if this operation is
- * unreliable for a given host, then the host itself needs to put a
- * timer on it, and set the host back to a consistent state prior to
- * returning.
- */
- static enum scsi_disposition scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
- {
- enum scsi_disposition rtn;
- struct scsi_host_template *hostt = scmd->device->host->hostt;
- if (!hostt->eh_device_reset_handler)
- return FAILED;
- rtn = hostt->eh_device_reset_handler(scmd);
- if (rtn == SUCCESS)
- __scsi_report_device_reset(scmd->device, NULL);
- return rtn;
- }
- /**
- * scsi_try_to_abort_cmd - Ask host to abort a SCSI command
- * @hostt: SCSI driver host template
- * @scmd: SCSI cmd used to send a target reset
- *
- * Return value:
- * SUCCESS, FAILED, or FAST_IO_FAIL
- *
- * Notes:
- * SUCCESS does not necessarily indicate that the command
- * has been aborted; it only indicates that the LLDDs
- * has cleared all references to that command.
- * LLDDs should return FAILED only if an abort was required
- * but could not be executed. LLDDs should return FAST_IO_FAIL
- * if the device is temporarily unavailable (eg due to a
- * link down on FibreChannel)
- */
- static enum scsi_disposition
- scsi_try_to_abort_cmd(struct scsi_host_template *hostt, struct scsi_cmnd *scmd)
- {
- if (!hostt->eh_abort_handler)
- return FAILED;
- return hostt->eh_abort_handler(scmd);
- }
- static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd)
- {
- if (scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd) != SUCCESS)
- if (scsi_try_bus_device_reset(scmd) != SUCCESS)
- if (scsi_try_target_reset(scmd) != SUCCESS)
- if (scsi_try_bus_reset(scmd) != SUCCESS)
- scsi_try_host_reset(scmd);
- }
- /**
- * scsi_eh_prep_cmnd - Save a scsi command info as part of error recovery
- * @scmd: SCSI command structure to hijack
- * @ses: structure to save restore information
- * @cmnd: CDB to send. Can be NULL if no new cmnd is needed
- * @cmnd_size: size in bytes of @cmnd (must be <= MAX_COMMAND_SIZE)
- * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored)
- *
- * This function is used to save a scsi command information before re-execution
- * as part of the error recovery process. If @sense_bytes is 0 the command
- * sent must be one that does not transfer any data. If @sense_bytes != 0
- * @cmnd is ignored and this functions sets up a REQUEST_SENSE command
- * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.
- */
- void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
- unsigned char *cmnd, int cmnd_size, unsigned sense_bytes)
- {
- struct scsi_device *sdev = scmd->device;
- /*
- * We need saved copies of a number of fields - this is because
- * error handling may need to overwrite these with different values
- * to run different commands, and once error handling is complete,
- * we will need to restore these values prior to running the actual
- * command.
- */
- ses->cmd_len = scmd->cmd_len;
- ses->data_direction = scmd->sc_data_direction;
- ses->sdb = scmd->sdb;
- ses->result = scmd->result;
- ses->resid_len = scmd->resid_len;
- ses->underflow = scmd->underflow;
- ses->prot_op = scmd->prot_op;
- ses->eh_eflags = scmd->eh_eflags;
- scmd->prot_op = SCSI_PROT_NORMAL;
- scmd->eh_eflags = 0;
- memcpy(ses->cmnd, scmd->cmnd, sizeof(ses->cmnd));
- memset(scmd->cmnd, 0, sizeof(scmd->cmnd));
- memset(&scmd->sdb, 0, sizeof(scmd->sdb));
- scmd->result = 0;
- scmd->resid_len = 0;
- if (sense_bytes) {
- scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE,
- sense_bytes);
- sg_init_one(&ses->sense_sgl, scmd->sense_buffer,
- scmd->sdb.length);
- scmd->sdb.table.sgl = &ses->sense_sgl;
- scmd->sc_data_direction = DMA_FROM_DEVICE;
- scmd->sdb.table.nents = scmd->sdb.table.orig_nents = 1;
- scmd->cmnd[0] = REQUEST_SENSE;
- scmd->cmnd[4] = scmd->sdb.length;
- scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
- } else {
- scmd->sc_data_direction = DMA_NONE;
- if (cmnd) {
- BUG_ON(cmnd_size > sizeof(scmd->cmnd));
- memcpy(scmd->cmnd, cmnd, cmnd_size);
- scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
- }
- }
- scmd->underflow = 0;
- if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN)
- scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) |
- (sdev->lun << 5 & 0xe0);
- /*
- * Zero the sense buffer. The scsi spec mandates that any
- * untransferred sense data should be interpreted as being zero.
- */
- memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
- }
- EXPORT_SYMBOL(scsi_eh_prep_cmnd);
- /**
- * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recovery
- * @scmd: SCSI command structure to restore
- * @ses: saved information from a coresponding call to scsi_eh_prep_cmnd
- *
- * Undo any damage done by above scsi_eh_prep_cmnd().
- */
- void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
- {
- /*
- * Restore original data
- */
- scmd->cmd_len = ses->cmd_len;
- memcpy(scmd->cmnd, ses->cmnd, sizeof(ses->cmnd));
- scmd->sc_data_direction = ses->data_direction;
- scmd->sdb = ses->sdb;
- scmd->result = ses->result;
- scmd->resid_len = ses->resid_len;
- scmd->underflow = ses->underflow;
- scmd->prot_op = ses->prot_op;
- scmd->eh_eflags = ses->eh_eflags;
- }
- EXPORT_SYMBOL(scsi_eh_restore_cmnd);
- /**
- * scsi_send_eh_cmnd - submit a scsi command as part of error recovery
- * @scmd: SCSI command structure to hijack
- * @cmnd: CDB to send
- * @cmnd_size: size in bytes of @cmnd
- * @timeout: timeout for this request
- * @sense_bytes: size of sense data to copy or 0
- *
- * This function is used to send a scsi command down to a target device
- * as part of the error recovery process. See also scsi_eh_prep_cmnd() above.
- *
- * Return value:
- * SUCCESS or FAILED or NEEDS_RETRY
- */
- static enum scsi_disposition scsi_send_eh_cmnd(struct scsi_cmnd *scmd,
- unsigned char *cmnd, int cmnd_size, int timeout, unsigned sense_bytes)
- {
- struct scsi_device *sdev = scmd->device;
- struct Scsi_Host *shost = sdev->host;
- DECLARE_COMPLETION_ONSTACK(done);
- unsigned long timeleft = timeout, delay;
- struct scsi_eh_save ses;
- const unsigned long stall_for = msecs_to_jiffies(100);
- int rtn;
- retry:
- scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);
- shost->eh_action = &done;
- scsi_log_send(scmd);
- scmd->submitter = SUBMITTED_BY_SCSI_ERROR_HANDLER;
- /*
- * Lock sdev->state_mutex to avoid that scsi_device_quiesce() can
- * change the SCSI device state after we have examined it and before
- * .queuecommand() is called.
- */
- mutex_lock(&sdev->state_mutex);
- while (sdev->sdev_state == SDEV_BLOCK && timeleft > 0) {
- mutex_unlock(&sdev->state_mutex);
- SCSI_LOG_ERROR_RECOVERY(5, sdev_printk(KERN_DEBUG, sdev,
- "%s: state %d <> %d\n", __func__, sdev->sdev_state,
- SDEV_BLOCK));
- delay = min(timeleft, stall_for);
- timeleft -= delay;
- msleep(jiffies_to_msecs(delay));
- mutex_lock(&sdev->state_mutex);
- }
- if (sdev->sdev_state != SDEV_BLOCK)
- rtn = shost->hostt->queuecommand(shost, scmd);
- else
- rtn = FAILED;
- mutex_unlock(&sdev->state_mutex);
- if (rtn) {
- if (timeleft > stall_for) {
- scsi_eh_restore_cmnd(scmd, &ses);
- timeleft -= stall_for;
- msleep(jiffies_to_msecs(stall_for));
- goto retry;
- }
- /* signal not to enter either branch of the if () below */
- timeleft = 0;
- rtn = FAILED;
- } else {
- timeleft = wait_for_completion_timeout(&done, timeout);
- rtn = SUCCESS;
- }
- shost->eh_action = NULL;
- scsi_log_completion(scmd, rtn);
- SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
- "%s timeleft: %ld\n",
- __func__, timeleft));
- /*
- * If there is time left scsi_eh_done got called, and we will examine
- * the actual status codes to see whether the command actually did
- * complete normally, else if we have a zero return and no time left,
- * the command must still be pending, so abort it and return FAILED.
- * If we never actually managed to issue the command, because
- * ->queuecommand() kept returning non zero, use the rtn = FAILED
- * value above (so don't execute either branch of the if)
- */
- if (timeleft) {
- rtn = scsi_eh_completed_normally(scmd);
- SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
- "%s: scsi_eh_completed_normally %x\n", __func__, rtn));
- switch (rtn) {
- case SUCCESS:
- case NEEDS_RETRY:
- case FAILED:
- break;
- case ADD_TO_MLQUEUE:
- rtn = NEEDS_RETRY;
- break;
- default:
- rtn = FAILED;
- break;
- }
- } else if (rtn != FAILED) {
- scsi_abort_eh_cmnd(scmd);
- rtn = FAILED;
- }
- scsi_eh_restore_cmnd(scmd, &ses);
- return rtn;
- }
- /**
- * scsi_request_sense - Request sense data from a particular target.
- * @scmd: SCSI cmd for request sense.
- *
- * Notes:
- * Some hosts automatically obtain this information, others require
- * that we obtain it on our own. This function will *not* return until
- * the command either times out, or it completes.
- */
- static enum scsi_disposition scsi_request_sense(struct scsi_cmnd *scmd)
- {
- return scsi_send_eh_cmnd(scmd, NULL, 0, scmd->device->eh_timeout, ~0);
- }
- static enum scsi_disposition
- scsi_eh_action(struct scsi_cmnd *scmd, enum scsi_disposition rtn)
- {
- if (!blk_rq_is_passthrough(scsi_cmd_to_rq(scmd))) {
- struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
- if (sdrv->eh_action)
- rtn = sdrv->eh_action(scmd, rtn);
- }
- return rtn;
- }
- /**
- * scsi_eh_finish_cmd - Handle a cmd that eh is finished with.
- * @scmd: Original SCSI cmd that eh has finished.
- * @done_q: Queue for processed commands.
- *
- * Notes:
- * We don't want to use the normal command completion while we are are
- * still handling errors - it may cause other commands to be queued,
- * and that would disturb what we are doing. Thus we really want to
- * keep a list of pending commands for final completion, and once we
- * are ready to leave error handling we handle completion for real.
- */
- void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q)
- {
- list_move_tail(&scmd->eh_entry, done_q);
- }
- EXPORT_SYMBOL(scsi_eh_finish_cmd);
- /**
- * scsi_eh_get_sense - Get device sense data.
- * @work_q: Queue of commands to process.
- * @done_q: Queue of processed commands.
- *
- * Description:
- * See if we need to request sense information. if so, then get it
- * now, so we have a better idea of what to do.
- *
- * Notes:
- * This has the unfortunate side effect that if a shost adapter does
- * not automatically request sense information, we end up shutting
- * it down before we request it.
- *
- * All drivers should request sense information internally these days,
- * so for now all I have to say is tough noogies if you end up in here.
- *
- * XXX: Long term this code should go away, but that needs an audit of
- * all LLDDs first.
- */
- int scsi_eh_get_sense(struct list_head *work_q,
- struct list_head *done_q)
- {
- struct scsi_cmnd *scmd, *next;
- struct Scsi_Host *shost;
- enum scsi_disposition rtn;
- /*
- * If SCSI_EH_ABORT_SCHEDULED has been set, it is timeout IO,
- * should not get sense.
- */
- list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
- if ((scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) ||
- SCSI_SENSE_VALID(scmd))
- continue;
- shost = scmd->device->host;
- if (scsi_host_eh_past_deadline(shost)) {
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "%s: skip request sense, past eh deadline\n",
- current->comm));
- break;
- }
- if (!scsi_status_is_check_condition(scmd->result))
- /*
- * don't request sense if there's no check condition
- * status because the error we're processing isn't one
- * that has a sense code (and some devices get
- * confused by sense requests out of the blue)
- */
- continue;
- SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd,
- "%s: requesting sense\n",
- current->comm));
- rtn = scsi_request_sense(scmd);
- if (rtn != SUCCESS)
- continue;
- SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
- "sense requested, result %x\n", scmd->result));
- SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense(scmd));
- rtn = scsi_decide_disposition(scmd);
- /*
- * if the result was normal, then just pass it along to the
- * upper level.
- */
- if (rtn == SUCCESS)
- /*
- * We don't want this command reissued, just finished
- * with the sense data, so set retries to the max
- * allowed to ensure it won't get reissued. If the user
- * has requested infinite retries, we also want to
- * finish this command, so force completion by setting
- * retries and allowed to the same value.
- */
- if (scmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
- scmd->retries = scmd->allowed = 1;
- else
- scmd->retries = scmd->allowed;
- else if (rtn != NEEDS_RETRY)
- continue;
- scsi_eh_finish_cmd(scmd, done_q);
- }
- return list_empty(work_q);
- }
- EXPORT_SYMBOL_GPL(scsi_eh_get_sense);
- /**
- * scsi_eh_tur - Send TUR to device.
- * @scmd: &scsi_cmnd to send TUR
- *
- * Return value:
- * 0 - Device is ready. 1 - Device NOT ready.
- */
- static int scsi_eh_tur(struct scsi_cmnd *scmd)
- {
- static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0};
- int retry_cnt = 1;
- enum scsi_disposition rtn;
- retry_tur:
- rtn = scsi_send_eh_cmnd(scmd, tur_command, 6,
- scmd->device->eh_timeout, 0);
- SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
- "%s return: %x\n", __func__, rtn));
- switch (rtn) {
- case NEEDS_RETRY:
- if (retry_cnt--)
- goto retry_tur;
- fallthrough;
- case SUCCESS:
- return 0;
- default:
- return 1;
- }
- }
- /**
- * scsi_eh_test_devices - check if devices are responding from error recovery.
- * @cmd_list: scsi commands in error recovery.
- * @work_q: queue for commands which still need more error recovery
- * @done_q: queue for commands which are finished
- * @try_stu: boolean on if a STU command should be tried in addition to TUR.
- *
- * Decription:
- * Tests if devices are in a working state. Commands to devices now in
- * a working state are sent to the done_q while commands to devices which
- * are still failing to respond are returned to the work_q for more
- * processing.
- **/
- static int scsi_eh_test_devices(struct list_head *cmd_list,
- struct list_head *work_q,
- struct list_head *done_q, int try_stu)
- {
- struct scsi_cmnd *scmd, *next;
- struct scsi_device *sdev;
- int finish_cmds;
- while (!list_empty(cmd_list)) {
- scmd = list_entry(cmd_list->next, struct scsi_cmnd, eh_entry);
- sdev = scmd->device;
- if (!try_stu) {
- if (scsi_host_eh_past_deadline(sdev->host)) {
- /* Push items back onto work_q */
- list_splice_init(cmd_list, work_q);
- SCSI_LOG_ERROR_RECOVERY(3,
- sdev_printk(KERN_INFO, sdev,
- "%s: skip test device, past eh deadline",
- current->comm));
- break;
- }
- }
- finish_cmds = !scsi_device_online(scmd->device) ||
- (try_stu && !scsi_eh_try_stu(scmd) &&
- !scsi_eh_tur(scmd)) ||
- !scsi_eh_tur(scmd);
- list_for_each_entry_safe(scmd, next, cmd_list, eh_entry)
- if (scmd->device == sdev) {
- if (finish_cmds &&
- (try_stu ||
- scsi_eh_action(scmd, SUCCESS) == SUCCESS))
- scsi_eh_finish_cmd(scmd, done_q);
- else
- list_move_tail(&scmd->eh_entry, work_q);
- }
- }
- return list_empty(work_q);
- }
- /**
- * scsi_eh_try_stu - Send START_UNIT to device.
- * @scmd: &scsi_cmnd to send START_UNIT
- *
- * Return value:
- * 0 - Device is ready. 1 - Device NOT ready.
- */
- static int scsi_eh_try_stu(struct scsi_cmnd *scmd)
- {
- static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0};
- if (scmd->device->allow_restart) {
- int i;
- enum scsi_disposition rtn = NEEDS_RETRY;
- for (i = 0; rtn == NEEDS_RETRY && i < 2; i++)
- rtn = scsi_send_eh_cmnd(scmd, stu_command, 6,
- scmd->device->eh_timeout, 0);
- if (rtn == SUCCESS)
- return 0;
- }
- return 1;
- }
- /**
- * scsi_eh_stu - send START_UNIT if needed
- * @shost: &scsi host being recovered.
- * @work_q: &list_head for pending commands.
- * @done_q: &list_head for processed commands.
- *
- * Notes:
- * If commands are failing due to not ready, initializing command required,
- * try revalidating the device, which will end up sending a start unit.
- */
- static int scsi_eh_stu(struct Scsi_Host *shost,
- struct list_head *work_q,
- struct list_head *done_q)
- {
- struct scsi_cmnd *scmd, *stu_scmd, *next;
- struct scsi_device *sdev;
- shost_for_each_device(sdev, shost) {
- if (scsi_host_eh_past_deadline(shost)) {
- SCSI_LOG_ERROR_RECOVERY(3,
- sdev_printk(KERN_INFO, sdev,
- "%s: skip START_UNIT, past eh deadline\n",
- current->comm));
- scsi_device_put(sdev);
- break;
- }
- stu_scmd = NULL;
- list_for_each_entry(scmd, work_q, eh_entry)
- if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) &&
- scsi_check_sense(scmd) == FAILED ) {
- stu_scmd = scmd;
- break;
- }
- if (!stu_scmd)
- continue;
- SCSI_LOG_ERROR_RECOVERY(3,
- sdev_printk(KERN_INFO, sdev,
- "%s: Sending START_UNIT\n",
- current->comm));
- if (!scsi_eh_try_stu(stu_scmd)) {
- if (!scsi_device_online(sdev) ||
- !scsi_eh_tur(stu_scmd)) {
- list_for_each_entry_safe(scmd, next,
- work_q, eh_entry) {
- if (scmd->device == sdev &&
- scsi_eh_action(scmd, SUCCESS) == SUCCESS)
- scsi_eh_finish_cmd(scmd, done_q);
- }
- }
- } else {
- SCSI_LOG_ERROR_RECOVERY(3,
- sdev_printk(KERN_INFO, sdev,
- "%s: START_UNIT failed\n",
- current->comm));
- }
- }
- return list_empty(work_q);
- }
- /**
- * scsi_eh_bus_device_reset - send bdr if needed
- * @shost: scsi host being recovered.
- * @work_q: &list_head for pending commands.
- * @done_q: &list_head for processed commands.
- *
- * Notes:
- * Try a bus device reset. Still, look to see whether we have multiple
- * devices that are jammed or not - if we have multiple devices, it
- * makes no sense to try bus_device_reset - we really would need to try
- * a bus_reset instead.
- */
- static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
- struct list_head *work_q,
- struct list_head *done_q)
- {
- struct scsi_cmnd *scmd, *bdr_scmd, *next;
- struct scsi_device *sdev;
- enum scsi_disposition rtn;
- shost_for_each_device(sdev, shost) {
- if (scsi_host_eh_past_deadline(shost)) {
- SCSI_LOG_ERROR_RECOVERY(3,
- sdev_printk(KERN_INFO, sdev,
- "%s: skip BDR, past eh deadline\n",
- current->comm));
- scsi_device_put(sdev);
- break;
- }
- bdr_scmd = NULL;
- list_for_each_entry(scmd, work_q, eh_entry)
- if (scmd->device == sdev) {
- bdr_scmd = scmd;
- break;
- }
- if (!bdr_scmd)
- continue;
- SCSI_LOG_ERROR_RECOVERY(3,
- sdev_printk(KERN_INFO, sdev,
- "%s: Sending BDR\n", current->comm));
- rtn = scsi_try_bus_device_reset(bdr_scmd);
- if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
- if (!scsi_device_online(sdev) ||
- rtn == FAST_IO_FAIL ||
- !scsi_eh_tur(bdr_scmd)) {
- list_for_each_entry_safe(scmd, next,
- work_q, eh_entry) {
- if (scmd->device == sdev &&
- scsi_eh_action(scmd, rtn) != FAILED)
- scsi_eh_finish_cmd(scmd,
- done_q);
- }
- }
- } else {
- SCSI_LOG_ERROR_RECOVERY(3,
- sdev_printk(KERN_INFO, sdev,
- "%s: BDR failed\n", current->comm));
- }
- }
- return list_empty(work_q);
- }
- /**
- * scsi_eh_target_reset - send target reset if needed
- * @shost: scsi host being recovered.
- * @work_q: &list_head for pending commands.
- * @done_q: &list_head for processed commands.
- *
- * Notes:
- * Try a target reset.
- */
- static int scsi_eh_target_reset(struct Scsi_Host *shost,
- struct list_head *work_q,
- struct list_head *done_q)
- {
- LIST_HEAD(tmp_list);
- LIST_HEAD(check_list);
- list_splice_init(work_q, &tmp_list);
- while (!list_empty(&tmp_list)) {
- struct scsi_cmnd *next, *scmd;
- enum scsi_disposition rtn;
- unsigned int id;
- if (scsi_host_eh_past_deadline(shost)) {
- /* push back on work queue for further processing */
- list_splice_init(&check_list, work_q);
- list_splice_init(&tmp_list, work_q);
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: Skip target reset, past eh deadline\n",
- current->comm));
- return list_empty(work_q);
- }
- scmd = list_entry(tmp_list.next, struct scsi_cmnd, eh_entry);
- id = scmd_id(scmd);
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: Sending target reset to target %d\n",
- current->comm, id));
- rtn = scsi_try_target_reset(scmd);
- if (rtn != SUCCESS && rtn != FAST_IO_FAIL)
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: Target reset failed"
- " target: %d\n",
- current->comm, id));
- list_for_each_entry_safe(scmd, next, &tmp_list, eh_entry) {
- if (scmd_id(scmd) != id)
- continue;
- if (rtn == SUCCESS)
- list_move_tail(&scmd->eh_entry, &check_list);
- else if (rtn == FAST_IO_FAIL)
- scsi_eh_finish_cmd(scmd, done_q);
- else
- /* push back on work queue for further processing */
- list_move(&scmd->eh_entry, work_q);
- }
- }
- return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
- }
- /**
- * scsi_eh_bus_reset - send a bus reset
- * @shost: &scsi host being recovered.
- * @work_q: &list_head for pending commands.
- * @done_q: &list_head for processed commands.
- */
- static int scsi_eh_bus_reset(struct Scsi_Host *shost,
- struct list_head *work_q,
- struct list_head *done_q)
- {
- struct scsi_cmnd *scmd, *chan_scmd, *next;
- LIST_HEAD(check_list);
- unsigned int channel;
- enum scsi_disposition rtn;
- /*
- * we really want to loop over the various channels, and do this on
- * a channel by channel basis. we should also check to see if any
- * of the failed commands are on soft_reset devices, and if so, skip
- * the reset.
- */
- for (channel = 0; channel <= shost->max_channel; channel++) {
- if (scsi_host_eh_past_deadline(shost)) {
- list_splice_init(&check_list, work_q);
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: skip BRST, past eh deadline\n",
- current->comm));
- return list_empty(work_q);
- }
- chan_scmd = NULL;
- list_for_each_entry(scmd, work_q, eh_entry) {
- if (channel == scmd_channel(scmd)) {
- chan_scmd = scmd;
- break;
- /*
- * FIXME add back in some support for
- * soft_reset devices.
- */
- }
- }
- if (!chan_scmd)
- continue;
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: Sending BRST chan: %d\n",
- current->comm, channel));
- rtn = scsi_try_bus_reset(chan_scmd);
- if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
- list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
- if (channel == scmd_channel(scmd)) {
- if (rtn == FAST_IO_FAIL)
- scsi_eh_finish_cmd(scmd,
- done_q);
- else
- list_move_tail(&scmd->eh_entry,
- &check_list);
- }
- }
- } else {
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: BRST failed chan: %d\n",
- current->comm, channel));
- }
- }
- return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
- }
- /**
- * scsi_eh_host_reset - send a host reset
- * @shost: host to be reset.
- * @work_q: &list_head for pending commands.
- * @done_q: &list_head for processed commands.
- */
- static int scsi_eh_host_reset(struct Scsi_Host *shost,
- struct list_head *work_q,
- struct list_head *done_q)
- {
- struct scsi_cmnd *scmd, *next;
- LIST_HEAD(check_list);
- enum scsi_disposition rtn;
- if (!list_empty(work_q)) {
- scmd = list_entry(work_q->next,
- struct scsi_cmnd, eh_entry);
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: Sending HRST\n",
- current->comm));
- rtn = scsi_try_host_reset(scmd);
- if (rtn == SUCCESS) {
- list_splice_init(work_q, &check_list);
- } else if (rtn == FAST_IO_FAIL) {
- list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
- scsi_eh_finish_cmd(scmd, done_q);
- }
- } else {
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: HRST failed\n",
- current->comm));
- }
- }
- return scsi_eh_test_devices(&check_list, work_q, done_q, 1);
- }
- /**
- * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
- * @work_q: &list_head for pending commands.
- * @done_q: &list_head for processed commands.
- */
- static void scsi_eh_offline_sdevs(struct list_head *work_q,
- struct list_head *done_q)
- {
- struct scsi_cmnd *scmd, *next;
- struct scsi_device *sdev;
- list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
- sdev_printk(KERN_INFO, scmd->device, "Device offlined - "
- "not ready after error recovery\n");
- sdev = scmd->device;
- mutex_lock(&sdev->state_mutex);
- scsi_device_set_state(sdev, SDEV_OFFLINE);
- mutex_unlock(&sdev->state_mutex);
- scsi_eh_finish_cmd(scmd, done_q);
- }
- return;
- }
- /**
- * scsi_noretry_cmd - determine if command should be failed fast
- * @scmd: SCSI cmd to examine.
- */
- bool scsi_noretry_cmd(struct scsi_cmnd *scmd)
- {
- struct request *req = scsi_cmd_to_rq(scmd);
- switch (host_byte(scmd->result)) {
- case DID_OK:
- break;
- case DID_TIME_OUT:
- goto check_type;
- case DID_BUS_BUSY:
- return !!(req->cmd_flags & REQ_FAILFAST_TRANSPORT);
- case DID_PARITY:
- return !!(req->cmd_flags & REQ_FAILFAST_DEV);
- case DID_ERROR:
- if (get_status_byte(scmd) == SAM_STAT_RESERVATION_CONFLICT)
- return false;
- fallthrough;
- case DID_SOFT_ERROR:
- return !!(req->cmd_flags & REQ_FAILFAST_DRIVER);
- }
- if (!scsi_status_is_check_condition(scmd->result))
- return false;
- check_type:
- /*
- * assume caller has checked sense and determined
- * the check condition was retryable.
- */
- if (req->cmd_flags & REQ_FAILFAST_DEV || blk_rq_is_passthrough(req))
- return true;
- return false;
- }
- /**
- * scsi_decide_disposition - Disposition a cmd on return from LLD.
- * @scmd: SCSI cmd to examine.
- *
- * Notes:
- * This is *only* called when we are examining the status after sending
- * out the actual data command. any commands that are queued for error
- * recovery (e.g. test_unit_ready) do *not* come through here.
- *
- * When this routine returns failed, it means the error handler thread
- * is woken. In cases where the error code indicates an error that
- * doesn't require the error handler read (i.e. we don't need to
- * abort/reset), this function should return SUCCESS.
- */
- enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *scmd)
- {
- enum scsi_disposition rtn;
- /*
- * if the device is offline, then we clearly just pass the result back
- * up to the top level.
- */
- if (!scsi_device_online(scmd->device)) {
- SCSI_LOG_ERROR_RECOVERY(5, scmd_printk(KERN_INFO, scmd,
- "%s: device offline - report as SUCCESS\n", __func__));
- return SUCCESS;
- }
- /*
- * first check the host byte, to see if there is anything in there
- * that would indicate what we need to do.
- */
- switch (host_byte(scmd->result)) {
- case DID_PASSTHROUGH:
- /*
- * no matter what, pass this through to the upper layer.
- * nuke this special code so that it looks like we are saying
- * did_ok.
- */
- scmd->result &= 0xff00ffff;
- return SUCCESS;
- case DID_OK:
- /*
- * looks good. drop through, and check the next byte.
- */
- break;
- case DID_ABORT:
- if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
- set_host_byte(scmd, DID_TIME_OUT);
- return SUCCESS;
- }
- fallthrough;
- case DID_NO_CONNECT:
- case DID_BAD_TARGET:
- /*
- * note - this means that we just report the status back
- * to the top level driver, not that we actually think
- * that it indicates SUCCESS.
- */
- return SUCCESS;
- case DID_SOFT_ERROR:
- /*
- * when the low level driver returns did_soft_error,
- * it is responsible for keeping an internal retry counter
- * in order to avoid endless loops (db)
- */
- goto maybe_retry;
- case DID_IMM_RETRY:
- return NEEDS_RETRY;
- case DID_REQUEUE:
- return ADD_TO_MLQUEUE;
- case DID_TRANSPORT_DISRUPTED:
- /*
- * LLD/transport was disrupted during processing of the IO.
- * The transport class is now blocked/blocking,
- * and the transport will decide what to do with the IO
- * based on its timers and recovery capablilities if
- * there are enough retries.
- */
- goto maybe_retry;
- case DID_TRANSPORT_FAILFAST:
- /*
- * The transport decided to failfast the IO (most likely
- * the fast io fail tmo fired), so send IO directly upwards.
- */
- return SUCCESS;
- case DID_TRANSPORT_MARGINAL:
- /*
- * caller has decided not to do retries on
- * abort success, so send IO directly upwards
- */
- return SUCCESS;
- case DID_ERROR:
- if (get_status_byte(scmd) == SAM_STAT_RESERVATION_CONFLICT)
- /*
- * execute reservation conflict processing code
- * lower down
- */
- break;
- fallthrough;
- case DID_BUS_BUSY:
- case DID_PARITY:
- goto maybe_retry;
- case DID_TIME_OUT:
- /*
- * when we scan the bus, we get timeout messages for
- * these commands if there is no device available.
- * other hosts report did_no_connect for the same thing.
- */
- if ((scmd->cmnd[0] == TEST_UNIT_READY ||
- scmd->cmnd[0] == INQUIRY)) {
- return SUCCESS;
- } else {
- return FAILED;
- }
- case DID_RESET:
- return SUCCESS;
- default:
- return FAILED;
- }
- /*
- * check the status byte to see if this indicates anything special.
- */
- switch (get_status_byte(scmd)) {
- case SAM_STAT_TASK_SET_FULL:
- scsi_handle_queue_full(scmd->device);
- /*
- * the case of trying to send too many commands to a
- * tagged queueing device.
- */
- fallthrough;
- case SAM_STAT_BUSY:
- /*
- * device can't talk to us at the moment. Should only
- * occur (SAM-3) when the task queue is empty, so will cause
- * the empty queue handling to trigger a stall in the
- * device.
- */
- return ADD_TO_MLQUEUE;
- case SAM_STAT_GOOD:
- if (scmd->cmnd[0] == REPORT_LUNS)
- scmd->device->sdev_target->expecting_lun_change = 0;
- scsi_handle_queue_ramp_up(scmd->device);
- fallthrough;
- case SAM_STAT_COMMAND_TERMINATED:
- return SUCCESS;
- case SAM_STAT_TASK_ABORTED:
- goto maybe_retry;
- case SAM_STAT_CHECK_CONDITION:
- rtn = scsi_check_sense(scmd);
- if (rtn == NEEDS_RETRY)
- goto maybe_retry;
- /* if rtn == FAILED, we have no sense information;
- * returning FAILED will wake the error handler thread
- * to collect the sense and redo the decide
- * disposition */
- return rtn;
- case SAM_STAT_CONDITION_MET:
- case SAM_STAT_INTERMEDIATE:
- case SAM_STAT_INTERMEDIATE_CONDITION_MET:
- case SAM_STAT_ACA_ACTIVE:
- /*
- * who knows? FIXME(eric)
- */
- return SUCCESS;
- case SAM_STAT_RESERVATION_CONFLICT:
- sdev_printk(KERN_INFO, scmd->device,
- "reservation conflict\n");
- set_scsi_ml_byte(scmd, SCSIML_STAT_RESV_CONFLICT);
- return SUCCESS; /* causes immediate i/o error */
- }
- return FAILED;
- maybe_retry:
- /* we requeue for retry because the error was retryable, and
- * the request was not marked fast fail. Note that above,
- * even if the request is marked fast fail, we still requeue
- * for queue congestion conditions (QUEUE_FULL or BUSY) */
- if (scsi_cmd_retry_allowed(scmd) && !scsi_noretry_cmd(scmd)) {
- return NEEDS_RETRY;
- } else {
- /*
- * no more retries - report this one back to upper level.
- */
- return SUCCESS;
- }
- }
- static enum rq_end_io_ret eh_lock_door_done(struct request *req,
- blk_status_t status)
- {
- blk_mq_free_request(req);
- return RQ_END_IO_NONE;
- }
- /**
- * scsi_eh_lock_door - Prevent medium removal for the specified device
- * @sdev: SCSI device to prevent medium removal
- *
- * Locking:
- * We must be called from process context.
- *
- * Notes:
- * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
- * head of the devices request queue, and continue.
- */
- static void scsi_eh_lock_door(struct scsi_device *sdev)
- {
- struct scsi_cmnd *scmd;
- struct request *req;
- req = scsi_alloc_request(sdev->request_queue, REQ_OP_DRV_IN, 0);
- if (IS_ERR(req))
- return;
- scmd = blk_mq_rq_to_pdu(req);
- scmd->cmnd[0] = ALLOW_MEDIUM_REMOVAL;
- scmd->cmnd[1] = 0;
- scmd->cmnd[2] = 0;
- scmd->cmnd[3] = 0;
- scmd->cmnd[4] = SCSI_REMOVAL_PREVENT;
- scmd->cmnd[5] = 0;
- scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
- scmd->allowed = 5;
- req->rq_flags |= RQF_QUIET;
- req->timeout = 10 * HZ;
- req->end_io = eh_lock_door_done;
- blk_execute_rq_nowait(req, true);
- }
- /**
- * scsi_restart_operations - restart io operations to the specified host.
- * @shost: Host we are restarting.
- *
- * Notes:
- * When we entered the error handler, we blocked all further i/o to
- * this device. we need to 'reverse' this process.
- */
- static void scsi_restart_operations(struct Scsi_Host *shost)
- {
- struct scsi_device *sdev;
- unsigned long flags;
- /*
- * If the door was locked, we need to insert a door lock request
- * onto the head of the SCSI request queue for the device. There
- * is no point trying to lock the door of an off-line device.
- */
- shost_for_each_device(sdev, shost) {
- if (scsi_device_online(sdev) && sdev->was_reset && sdev->locked) {
- scsi_eh_lock_door(sdev);
- sdev->was_reset = 0;
- }
- }
- /*
- * next free up anything directly waiting upon the host. this
- * will be requests for character device operations, and also for
- * ioctls to queued block devices.
- */
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost, "waking up host to restart\n"));
- spin_lock_irqsave(shost->host_lock, flags);
- if (scsi_host_set_state(shost, SHOST_RUNNING))
- if (scsi_host_set_state(shost, SHOST_CANCEL))
- BUG_ON(scsi_host_set_state(shost, SHOST_DEL));
- spin_unlock_irqrestore(shost->host_lock, flags);
- wake_up(&shost->host_wait);
- /*
- * finally we need to re-initiate requests that may be pending. we will
- * have had everything blocked while error handling is taking place, and
- * now that error recovery is done, we will need to ensure that these
- * requests are started.
- */
- scsi_run_host_queues(shost);
- /*
- * if eh is active and host_eh_scheduled is pending we need to re-run
- * recovery. we do this check after scsi_run_host_queues() to allow
- * everything pent up since the last eh run a chance to make forward
- * progress before we sync again. Either we'll immediately re-run
- * recovery or scsi_device_unbusy() will wake us again when these
- * pending commands complete.
- */
- spin_lock_irqsave(shost->host_lock, flags);
- if (shost->host_eh_scheduled)
- if (scsi_host_set_state(shost, SHOST_RECOVERY))
- WARN_ON(scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY));
- spin_unlock_irqrestore(shost->host_lock, flags);
- }
- /**
- * scsi_eh_ready_devs - check device ready state and recover if not.
- * @shost: host to be recovered.
- * @work_q: &list_head for pending commands.
- * @done_q: &list_head for processed commands.
- */
- void scsi_eh_ready_devs(struct Scsi_Host *shost,
- struct list_head *work_q,
- struct list_head *done_q)
- {
- if (!scsi_eh_stu(shost, work_q, done_q))
- if (!scsi_eh_bus_device_reset(shost, work_q, done_q))
- if (!scsi_eh_target_reset(shost, work_q, done_q))
- if (!scsi_eh_bus_reset(shost, work_q, done_q))
- if (!scsi_eh_host_reset(shost, work_q, done_q))
- scsi_eh_offline_sdevs(work_q,
- done_q);
- }
- EXPORT_SYMBOL_GPL(scsi_eh_ready_devs);
- /**
- * scsi_eh_flush_done_q - finish processed commands or retry them.
- * @done_q: list_head of processed commands.
- */
- void scsi_eh_flush_done_q(struct list_head *done_q)
- {
- struct scsi_cmnd *scmd, *next;
- list_for_each_entry_safe(scmd, next, done_q, eh_entry) {
- list_del_init(&scmd->eh_entry);
- if (scsi_device_online(scmd->device) &&
- !scsi_noretry_cmd(scmd) && scsi_cmd_retry_allowed(scmd) &&
- scsi_eh_should_retry_cmd(scmd)) {
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "%s: flush retry cmd\n",
- current->comm));
- scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
- } else {
- /*
- * If just we got sense for the device (called
- * scsi_eh_get_sense), scmd->result is already
- * set, do not set DID_TIME_OUT.
- */
- if (!scmd->result)
- scmd->result |= (DID_TIME_OUT << 16);
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "%s: flush finish cmd\n",
- current->comm));
- scsi_finish_command(scmd);
- }
- }
- }
- EXPORT_SYMBOL(scsi_eh_flush_done_q);
- /**
- * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
- * @shost: Host to unjam.
- *
- * Notes:
- * When we come in here, we *know* that all commands on the bus have
- * either completed, failed or timed out. we also know that no further
- * commands are being sent to the host, so things are relatively quiet
- * and we have freedom to fiddle with things as we wish.
- *
- * This is only the *default* implementation. it is possible for
- * individual drivers to supply their own version of this function, and
- * if the maintainer wishes to do this, it is strongly suggested that
- * this function be taken as a template and modified. this function
- * was designed to correctly handle problems for about 95% of the
- * different cases out there, and it should always provide at least a
- * reasonable amount of error recovery.
- *
- * Any command marked 'failed' or 'timeout' must eventually have
- * scsi_finish_cmd() called for it. we do all of the retry stuff
- * here, so when we restart the host after we return it should have an
- * empty queue.
- */
- static void scsi_unjam_host(struct Scsi_Host *shost)
- {
- unsigned long flags;
- LIST_HEAD(eh_work_q);
- LIST_HEAD(eh_done_q);
- spin_lock_irqsave(shost->host_lock, flags);
- list_splice_init(&shost->eh_cmd_q, &eh_work_q);
- spin_unlock_irqrestore(shost->host_lock, flags);
- SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q));
- if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q))
- scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
- spin_lock_irqsave(shost->host_lock, flags);
- if (shost->eh_deadline != -1)
- shost->last_reset = 0;
- spin_unlock_irqrestore(shost->host_lock, flags);
- scsi_eh_flush_done_q(&eh_done_q);
- }
- /**
- * scsi_error_handler - SCSI error handler thread
- * @data: Host for which we are running.
- *
- * Notes:
- * This is the main error handling loop. This is run as a kernel thread
- * for every SCSI host and handles all error handling activity.
- */
- int scsi_error_handler(void *data)
- {
- struct Scsi_Host *shost = data;
- /*
- * We use TASK_INTERRUPTIBLE so that the thread is not
- * counted against the load average as a running process.
- * We never actually get interrupted because kthread_run
- * disables signal delivery for the created thread.
- */
- while (true) {
- /*
- * The sequence in kthread_stop() sets the stop flag first
- * then wakes the process. To avoid missed wakeups, the task
- * should always be in a non running state before the stop
- * flag is checked
- */
- set_current_state(TASK_INTERRUPTIBLE);
- if (kthread_should_stop())
- break;
- if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
- shost->host_failed != scsi_host_busy(shost)) {
- SCSI_LOG_ERROR_RECOVERY(1,
- shost_printk(KERN_INFO, shost,
- "scsi_eh_%d: sleeping\n",
- shost->host_no));
- schedule();
- continue;
- }
- __set_current_state(TASK_RUNNING);
- SCSI_LOG_ERROR_RECOVERY(1,
- shost_printk(KERN_INFO, shost,
- "scsi_eh_%d: waking up %d/%d/%d\n",
- shost->host_no, shost->host_eh_scheduled,
- shost->host_failed,
- scsi_host_busy(shost)));
- /*
- * We have a host that is failing for some reason. Figure out
- * what we need to do to get it up and online again (if we can).
- * If we fail, we end up taking the thing offline.
- */
- if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) {
- SCSI_LOG_ERROR_RECOVERY(1,
- shost_printk(KERN_ERR, shost,
- "scsi_eh_%d: unable to autoresume\n",
- shost->host_no));
- continue;
- }
- if (shost->transportt->eh_strategy_handler)
- shost->transportt->eh_strategy_handler(shost);
- else
- scsi_unjam_host(shost);
- /* All scmds have been handled */
- shost->host_failed = 0;
- /*
- * Note - if the above fails completely, the action is to take
- * individual devices offline and flush the queue of any
- * outstanding requests that may have been pending. When we
- * restart, we restart any I/O to any other devices on the bus
- * which are still online.
- */
- scsi_restart_operations(shost);
- if (!shost->eh_noresume)
- scsi_autopm_put_host(shost);
- }
- __set_current_state(TASK_RUNNING);
- SCSI_LOG_ERROR_RECOVERY(1,
- shost_printk(KERN_INFO, shost,
- "Error handler scsi_eh_%d exiting\n",
- shost->host_no));
- shost->ehandler = NULL;
- return 0;
- }
- /*
- * Function: scsi_report_bus_reset()
- *
- * Purpose: Utility function used by low-level drivers to report that
- * they have observed a bus reset on the bus being handled.
- *
- * Arguments: shost - Host in question
- * channel - channel on which reset was observed.
- *
- * Returns: Nothing
- *
- * Lock status: Host lock must be held.
- *
- * Notes: This only needs to be called if the reset is one which
- * originates from an unknown location. Resets originated
- * by the mid-level itself don't need to call this, but there
- * should be no harm.
- *
- * The main purpose of this is to make sure that a CHECK_CONDITION
- * is properly treated.
- */
- void scsi_report_bus_reset(struct Scsi_Host *shost, int channel)
- {
- struct scsi_device *sdev;
- __shost_for_each_device(sdev, shost) {
- if (channel == sdev_channel(sdev))
- __scsi_report_device_reset(sdev, NULL);
- }
- }
- EXPORT_SYMBOL(scsi_report_bus_reset);
- /*
- * Function: scsi_report_device_reset()
- *
- * Purpose: Utility function used by low-level drivers to report that
- * they have observed a device reset on the device being handled.
- *
- * Arguments: shost - Host in question
- * channel - channel on which reset was observed
- * target - target on which reset was observed
- *
- * Returns: Nothing
- *
- * Lock status: Host lock must be held
- *
- * Notes: This only needs to be called if the reset is one which
- * originates from an unknown location. Resets originated
- * by the mid-level itself don't need to call this, but there
- * should be no harm.
- *
- * The main purpose of this is to make sure that a CHECK_CONDITION
- * is properly treated.
- */
- void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target)
- {
- struct scsi_device *sdev;
- __shost_for_each_device(sdev, shost) {
- if (channel == sdev_channel(sdev) &&
- target == sdev_id(sdev))
- __scsi_report_device_reset(sdev, NULL);
- }
- }
- EXPORT_SYMBOL(scsi_report_device_reset);
- /**
- * scsi_ioctl_reset: explicitly reset a host/bus/target/device
- * @dev: scsi_device to operate on
- * @arg: reset type (see sg.h)
- */
- int
- scsi_ioctl_reset(struct scsi_device *dev, int __user *arg)
- {
- struct scsi_cmnd *scmd;
- struct Scsi_Host *shost = dev->host;
- struct request *rq;
- unsigned long flags;
- int error = 0, val;
- enum scsi_disposition rtn;
- if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
- return -EACCES;
- error = get_user(val, arg);
- if (error)
- return error;
- if (scsi_autopm_get_host(shost) < 0)
- return -EIO;
- error = -EIO;
- rq = kzalloc(sizeof(struct request) + sizeof(struct scsi_cmnd) +
- shost->hostt->cmd_size, GFP_KERNEL);
- if (!rq)
- goto out_put_autopm_host;
- blk_rq_init(NULL, rq);
- scmd = (struct scsi_cmnd *)(rq + 1);
- scsi_init_command(dev, scmd);
- scmd->submitter = SUBMITTED_BY_SCSI_RESET_IOCTL;
- memset(&scmd->sdb, 0, sizeof(scmd->sdb));
- scmd->cmd_len = 0;
- scmd->sc_data_direction = DMA_BIDIRECTIONAL;
- spin_lock_irqsave(shost->host_lock, flags);
- shost->tmf_in_progress = 1;
- spin_unlock_irqrestore(shost->host_lock, flags);
- switch (val & ~SG_SCSI_RESET_NO_ESCALATE) {
- case SG_SCSI_RESET_NOTHING:
- rtn = SUCCESS;
- break;
- case SG_SCSI_RESET_DEVICE:
- rtn = scsi_try_bus_device_reset(scmd);
- if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
- break;
- fallthrough;
- case SG_SCSI_RESET_TARGET:
- rtn = scsi_try_target_reset(scmd);
- if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
- break;
- fallthrough;
- case SG_SCSI_RESET_BUS:
- rtn = scsi_try_bus_reset(scmd);
- if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
- break;
- fallthrough;
- case SG_SCSI_RESET_HOST:
- rtn = scsi_try_host_reset(scmd);
- if (rtn == SUCCESS)
- break;
- fallthrough;
- default:
- rtn = FAILED;
- break;
- }
- error = (rtn == SUCCESS) ? 0 : -EIO;
- spin_lock_irqsave(shost->host_lock, flags);
- shost->tmf_in_progress = 0;
- spin_unlock_irqrestore(shost->host_lock, flags);
- /*
- * be sure to wake up anyone who was sleeping or had their queue
- * suspended while we performed the TMF.
- */
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "waking up host to restart after TMF\n"));
- wake_up(&shost->host_wait);
- scsi_run_host_queues(shost);
- kfree(rq);
- out_put_autopm_host:
- scsi_autopm_put_host(shost);
- return error;
- }
- bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd,
- struct scsi_sense_hdr *sshdr)
- {
- return scsi_normalize_sense(cmd->sense_buffer,
- SCSI_SENSE_BUFFERSIZE, sshdr);
- }
- EXPORT_SYMBOL(scsi_command_normalize_sense);
- /**
- * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format)
- * @sense_buffer: byte array of sense data
- * @sb_len: number of valid bytes in sense_buffer
- * @info_out: pointer to 64 integer where 8 or 4 byte information
- * field will be placed if found.
- *
- * Return value:
- * true if information field found, false if not found.
- */
- bool scsi_get_sense_info_fld(const u8 *sense_buffer, int sb_len,
- u64 *info_out)
- {
- const u8 * ucp;
- if (sb_len < 7)
- return false;
- switch (sense_buffer[0] & 0x7f) {
- case 0x70:
- case 0x71:
- if (sense_buffer[0] & 0x80) {
- *info_out = get_unaligned_be32(&sense_buffer[3]);
- return true;
- }
- return false;
- case 0x72:
- case 0x73:
- ucp = scsi_sense_desc_find(sense_buffer, sb_len,
- 0 /* info desc */);
- if (ucp && (0xa == ucp[1])) {
- *info_out = get_unaligned_be64(&ucp[4]);
- return true;
- }
- return false;
- default:
- return false;
- }
- }
- EXPORT_SYMBOL(scsi_get_sense_info_fld);
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