| // 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 (andmike@us.ibm.com) |
| * |
| * Forward port of Russell King's (rmk@arm.linux.org.uk) changes and |
| * minor cleanups. |
| * September 30, 2002 Mike Anderson (andmike@us.ibm.com) |
| */ |
| |
| #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_times_out(), 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 (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(&scmd->rcu, scsi_eh_inc_host_failed); |
| } |
| |
| /** |
| * scsi_times_out - 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_times_out(struct request *req) |
| { |
| struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req); |
| enum blk_eh_timer_return rtn = BLK_EH_DONE; |
| struct Scsi_Host *host = scmd->device->host; |
| |
| trace_scsi_dispatch_cmd_timeout(scmd); |
| scsi_log_completion(scmd, TIMEOUT_ERROR); |
| |
| if (host->eh_deadline != -1 && !host->last_reset) |
| host->last_reset = jiffies; |
| |
| if (host->hostt->eh_timed_out) |
| rtn = host->hostt->eh_timed_out(scmd); |
| |
| if (rtn == BLK_EH_DONE) { |
| /* |
| * Set the command to complete first in order to prevent a real |
| * completion from releasing the command while error handling |
| * is using it. If the command was already completed, then the |
| * lower level driver beat the timeout handler, and it is safe |
| * to return without escalating error recovery. |
| * |
| * If timeout handling lost the race to a real completion, the |
| * block layer may ignore that due to a fake timeout injection, |
| * so return RESET_TIMER to allow error handling another shot |
| * at this command. |
| */ |
| if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state)) |
| return BLK_EH_RESET_TIMER; |
| if (scsi_abort_command(scmd) != SUCCESS) { |
| set_host_byte(scmd, DID_TIME_OUT); |
| scsi_eh_scmd_add(scmd); |
| } |
| } |
| |
| return rtn; |
| } |
| |
| /** |
| * 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, |
| "Warning! Received an indication that the " |
| "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, |
| "Warning! Received an indication that the " |
| "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); |
| } |
| } |
| |
| /** |
| * 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_host_byte(scmd, DID_ALLOC_FAILURE); |
| return SUCCESS; |
| } |
| fallthrough; |
| case COPY_ABORTED: |
| case VOLUME_OVERFLOW: |
| case MISCOMPARE: |
| case BLANK_CHECK: |
| set_host_byte(scmd, DID_TARGET_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_host_byte(scmd, DID_MEDIUM_ERROR); |
| return SUCCESS; |
| } |
| return NEEDS_RETRY; |
| |
| case HARDWARE_ERROR: |
| if (scmd->device->retry_hwerror) |
| return ADD_TO_MLQUEUE; |
| else |
| set_host_byte(scmd, DID_TARGET_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_host_byte(scmd, DID_TARGET_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. |
| */ |
| int 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 0; |
| fallthrough; |
| case DID_SOFT_ERROR: |
| return req->cmd_flags & REQ_FAILFAST_DRIVER; |
| } |
| |
| if (!scsi_status_is_check_condition(scmd->result)) |
| return 0; |
| |
| 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 1; |
| |
| return 0; |
| } |
| |
| /** |
| * 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_host_byte(scmd, DID_NEXUS_FAILURE); |
| 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 void eh_lock_door_done(struct request *req, blk_status_t status) |
| { |
| blk_mq_free_request(req); |
| } |
| |
| /** |
| * 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); |