mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 10:36:42 +07:00
95bb335c0e
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2129 lines
57 KiB
C
2129 lines
57 KiB
C
/*
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* scsi_error.c Copyright (C) 1997 Eric Youngdale
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*
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* SCSI error/timeout handling
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* Initial versions: Eric Youngdale. Based upon conversations with
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* Leonard Zubkoff and David Miller at Linux Expo,
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* ideas originating from all over the place.
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*
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* Restructured scsi_unjam_host and associated functions.
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* September 04, 2002 Mike Anderson (andmike@us.ibm.com)
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*
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* Forward port of Russell King's (rmk@arm.linux.org.uk) changes and
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* minor cleanups.
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* September 30, 2002 Mike Anderson (andmike@us.ibm.com)
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*/
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/gfp.h>
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#include <linux/timer.h>
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#include <linux/string.h>
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#include <linux/kernel.h>
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#include <linux/freezer.h>
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#include <linux/kthread.h>
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#include <linux/interrupt.h>
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#include <linux/blkdev.h>
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#include <linux/delay.h>
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#include <scsi/scsi.h>
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#include <scsi/scsi_cmnd.h>
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#include <scsi/scsi_dbg.h>
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#include <scsi/scsi_device.h>
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#include <scsi/scsi_eh.h>
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#include <scsi/scsi_transport.h>
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#include <scsi/scsi_host.h>
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#include <scsi/scsi_ioctl.h>
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#include "scsi_priv.h"
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#include "scsi_logging.h"
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#include "scsi_transport_api.h"
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#include <trace/events/scsi.h>
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#define SENSE_TIMEOUT (10*HZ)
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/*
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* These should *probably* be handled by the host itself.
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* Since it is allowed to sleep, it probably should.
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*/
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#define BUS_RESET_SETTLE_TIME (10)
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#define HOST_RESET_SETTLE_TIME (10)
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/* called with shost->host_lock held */
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void scsi_eh_wakeup(struct Scsi_Host *shost)
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{
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if (shost->host_busy == shost->host_failed) {
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trace_scsi_eh_wakeup(shost);
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wake_up_process(shost->ehandler);
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SCSI_LOG_ERROR_RECOVERY(5,
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printk("Waking error handler thread\n"));
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}
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}
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/**
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* scsi_schedule_eh - schedule EH for SCSI host
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* @shost: SCSI host to invoke error handling on.
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*
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* Schedule SCSI EH without scmd.
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*/
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void scsi_schedule_eh(struct Scsi_Host *shost)
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{
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unsigned long flags;
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spin_lock_irqsave(shost->host_lock, flags);
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if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 ||
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scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) {
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shost->host_eh_scheduled++;
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scsi_eh_wakeup(shost);
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}
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spin_unlock_irqrestore(shost->host_lock, flags);
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}
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EXPORT_SYMBOL_GPL(scsi_schedule_eh);
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/**
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* scsi_eh_scmd_add - add scsi cmd to error handling.
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* @scmd: scmd to run eh on.
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* @eh_flag: optional SCSI_EH flag.
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*
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* Return value:
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* 0 on failure.
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*/
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int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag)
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{
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struct Scsi_Host *shost = scmd->device->host;
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unsigned long flags;
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int ret = 0;
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if (!shost->ehandler)
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return 0;
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spin_lock_irqsave(shost->host_lock, flags);
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if (scsi_host_set_state(shost, SHOST_RECOVERY))
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if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY))
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goto out_unlock;
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ret = 1;
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scmd->eh_eflags |= eh_flag;
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list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q);
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shost->host_failed++;
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scsi_eh_wakeup(shost);
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out_unlock:
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spin_unlock_irqrestore(shost->host_lock, flags);
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return ret;
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}
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/**
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* scsi_times_out - Timeout function for normal scsi commands.
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* @req: request that is timing out.
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*
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* Notes:
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* We do not need to lock this. There is the potential for a race
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* only in that the normal completion handling might run, but if the
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* normal completion function determines that the timer has already
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* fired, then it mustn't do anything.
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*/
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enum blk_eh_timer_return scsi_times_out(struct request *req)
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{
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struct scsi_cmnd *scmd = req->special;
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enum blk_eh_timer_return rtn = BLK_EH_NOT_HANDLED;
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trace_scsi_dispatch_cmd_timeout(scmd);
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scsi_log_completion(scmd, TIMEOUT_ERROR);
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if (scmd->device->host->transportt->eh_timed_out)
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rtn = scmd->device->host->transportt->eh_timed_out(scmd);
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else if (scmd->device->host->hostt->eh_timed_out)
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rtn = scmd->device->host->hostt->eh_timed_out(scmd);
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if (unlikely(rtn == BLK_EH_NOT_HANDLED &&
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!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) {
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scmd->result |= DID_TIME_OUT << 16;
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rtn = BLK_EH_HANDLED;
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}
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return rtn;
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}
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/**
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* scsi_block_when_processing_errors - Prevent cmds from being queued.
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* @sdev: Device on which we are performing recovery.
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*
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* Description:
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* We block until the host is out of error recovery, and then check to
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* see whether the host or the device is offline.
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*
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* Return value:
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* 0 when dev was taken offline by error recovery. 1 OK to proceed.
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*/
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int scsi_block_when_processing_errors(struct scsi_device *sdev)
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{
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int online;
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wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host));
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online = scsi_device_online(sdev);
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SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __func__,
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online));
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return online;
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}
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EXPORT_SYMBOL(scsi_block_when_processing_errors);
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#ifdef CONFIG_SCSI_LOGGING
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/**
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* scsi_eh_prt_fail_stats - Log info on failures.
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* @shost: scsi host being recovered.
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* @work_q: Queue of scsi cmds to process.
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*/
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static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost,
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struct list_head *work_q)
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{
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struct scsi_cmnd *scmd;
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struct scsi_device *sdev;
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int total_failures = 0;
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int cmd_failed = 0;
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int cmd_cancel = 0;
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int devices_failed = 0;
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shost_for_each_device(sdev, shost) {
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list_for_each_entry(scmd, work_q, eh_entry) {
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if (scmd->device == sdev) {
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++total_failures;
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if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD)
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++cmd_cancel;
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else
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++cmd_failed;
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}
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}
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if (cmd_cancel || cmd_failed) {
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SCSI_LOG_ERROR_RECOVERY(3,
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sdev_printk(KERN_INFO, sdev,
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"%s: cmds failed: %d, cancel: %d\n",
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__func__, cmd_failed,
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cmd_cancel));
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cmd_cancel = 0;
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cmd_failed = 0;
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++devices_failed;
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}
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}
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SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d"
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" devices require eh work\n",
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total_failures, devices_failed));
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}
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#endif
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/**
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* scsi_check_sense - Examine scsi cmd sense
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* @scmd: Cmd to have sense checked.
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*
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* Return value:
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* SUCCESS or FAILED or NEEDS_RETRY
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*
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* Notes:
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* When a deferred error is detected the current command has
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* not been executed and needs retrying.
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*/
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static int scsi_check_sense(struct scsi_cmnd *scmd)
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{
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struct scsi_device *sdev = scmd->device;
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struct scsi_sense_hdr sshdr;
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if (! scsi_command_normalize_sense(scmd, &sshdr))
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return FAILED; /* no valid sense data */
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if (scsi_sense_is_deferred(&sshdr))
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return NEEDS_RETRY;
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if (sdev->scsi_dh_data && sdev->scsi_dh_data->scsi_dh &&
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sdev->scsi_dh_data->scsi_dh->check_sense) {
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int rc;
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rc = sdev->scsi_dh_data->scsi_dh->check_sense(sdev, &sshdr);
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if (rc != SCSI_RETURN_NOT_HANDLED)
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return rc;
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/* handler does not care. Drop down to default handling */
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}
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/*
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* Previous logic looked for FILEMARK, EOM or ILI which are
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* mainly associated with tapes and returned SUCCESS.
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*/
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if (sshdr.response_code == 0x70) {
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/* fixed format */
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if (scmd->sense_buffer[2] & 0xe0)
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return SUCCESS;
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} else {
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/*
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* descriptor format: look for "stream commands sense data
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* descriptor" (see SSC-3). Assume single sense data
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* descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
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*/
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if ((sshdr.additional_length > 3) &&
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(scmd->sense_buffer[8] == 0x4) &&
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(scmd->sense_buffer[11] & 0xe0))
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return SUCCESS;
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}
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switch (sshdr.sense_key) {
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case NO_SENSE:
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return SUCCESS;
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case RECOVERED_ERROR:
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return /* soft_error */ SUCCESS;
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case ABORTED_COMMAND:
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if (sshdr.asc == 0x10) /* DIF */
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return SUCCESS;
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return NEEDS_RETRY;
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case NOT_READY:
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case UNIT_ATTENTION:
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/*
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* if we are expecting a cc/ua because of a bus reset that we
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* performed, treat this just as a retry. otherwise this is
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* information that we should pass up to the upper-level driver
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* so that we can deal with it there.
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*/
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if (scmd->device->expecting_cc_ua) {
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scmd->device->expecting_cc_ua = 0;
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return NEEDS_RETRY;
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}
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/*
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* if the device is in the process of becoming ready, we
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* should retry.
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*/
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if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01))
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return NEEDS_RETRY;
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/*
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* if the device is not started, we need to wake
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* the error handler to start the motor
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*/
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if (scmd->device->allow_restart &&
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(sshdr.asc == 0x04) && (sshdr.ascq == 0x02))
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return FAILED;
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if (blk_barrier_rq(scmd->request))
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/*
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* barrier requests should always retry on UA
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* otherwise block will get a spurious error
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*/
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return NEEDS_RETRY;
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else
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/*
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* for normal (non barrier) commands, pass the
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* UA upwards for a determination in the
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* completion functions
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*/
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return SUCCESS;
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/* these three are not supported */
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case COPY_ABORTED:
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case VOLUME_OVERFLOW:
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case MISCOMPARE:
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return SUCCESS;
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case MEDIUM_ERROR:
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if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */
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sshdr.asc == 0x13 || /* AMNF DATA FIELD */
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sshdr.asc == 0x14) { /* RECORD NOT FOUND */
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return SUCCESS;
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}
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return NEEDS_RETRY;
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case HARDWARE_ERROR:
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if (scmd->device->retry_hwerror)
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return ADD_TO_MLQUEUE;
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else
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return SUCCESS;
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case ILLEGAL_REQUEST:
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case BLANK_CHECK:
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case DATA_PROTECT:
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default:
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return SUCCESS;
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}
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}
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static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
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{
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struct scsi_host_template *sht = sdev->host->hostt;
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struct scsi_device *tmp_sdev;
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if (!sht->change_queue_depth ||
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sdev->queue_depth >= sdev->max_queue_depth)
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return;
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if (time_before(jiffies,
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sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
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return;
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if (time_before(jiffies,
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sdev->last_queue_full_time + sdev->queue_ramp_up_period))
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return;
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/*
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* Walk all devices of a target and do
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* ramp up on them.
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*/
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shost_for_each_device(tmp_sdev, sdev->host) {
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if (tmp_sdev->channel != sdev->channel ||
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tmp_sdev->id != sdev->id ||
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tmp_sdev->queue_depth == sdev->max_queue_depth)
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continue;
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/*
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* call back into LLD to increase queue_depth by one
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* with ramp up reason code.
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*/
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sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1,
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SCSI_QDEPTH_RAMP_UP);
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sdev->last_queue_ramp_up = jiffies;
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}
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}
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static void scsi_handle_queue_full(struct scsi_device *sdev)
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{
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struct scsi_host_template *sht = sdev->host->hostt;
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struct scsi_device *tmp_sdev;
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if (!sht->change_queue_depth)
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return;
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shost_for_each_device(tmp_sdev, sdev->host) {
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if (tmp_sdev->channel != sdev->channel ||
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tmp_sdev->id != sdev->id)
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continue;
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/*
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* We do not know the number of commands that were at
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* the device when we got the queue full so we start
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* from the highest possible value and work our way down.
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*/
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sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth - 1,
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SCSI_QDEPTH_QFULL);
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}
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}
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/**
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* scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
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* @scmd: SCSI cmd to examine.
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*
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* Notes:
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* This is *only* called when we are examining the status of commands
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* queued during error recovery. the main difference here is that we
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* don't allow for the possibility of retries here, and we are a lot
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* more restrictive about what we consider acceptable.
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*/
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static int scsi_eh_completed_normally(struct scsi_cmnd *scmd)
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{
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/*
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* first check the host byte, to see if there is anything in there
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* that would indicate what we need to do.
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*/
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if (host_byte(scmd->result) == DID_RESET) {
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/*
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* rats. we are already in the error handler, so we now
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* get to try and figure out what to do next. if the sense
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* is valid, we have a pretty good idea of what to do.
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* if not, we mark it as FAILED.
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*/
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return scsi_check_sense(scmd);
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}
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if (host_byte(scmd->result) != DID_OK)
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return FAILED;
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/*
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* next, check the message byte.
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*/
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if (msg_byte(scmd->result) != COMMAND_COMPLETE)
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return FAILED;
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/*
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* now, check the status byte to see if this indicates
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* anything special.
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*/
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switch (status_byte(scmd->result)) {
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case GOOD:
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scsi_handle_queue_ramp_up(scmd->device);
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case COMMAND_TERMINATED:
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return SUCCESS;
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case CHECK_CONDITION:
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return scsi_check_sense(scmd);
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case CONDITION_GOOD:
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case INTERMEDIATE_GOOD:
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case INTERMEDIATE_C_GOOD:
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/*
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* who knows? FIXME(eric)
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*/
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return SUCCESS;
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case RESERVATION_CONFLICT:
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/*
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* let issuer deal with this, it could be just fine
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*/
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return SUCCESS;
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case QUEUE_FULL:
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scsi_handle_queue_full(scmd->device);
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/* fall through */
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case BUSY:
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default:
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return FAILED;
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}
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return FAILED;
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}
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|
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/**
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* scsi_eh_done - Completion function for error handling.
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* @scmd: Cmd that is done.
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*/
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static void scsi_eh_done(struct scsi_cmnd *scmd)
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{
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struct completion *eh_action;
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SCSI_LOG_ERROR_RECOVERY(3,
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printk("%s scmd: %p result: %x\n",
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__func__, scmd, scmd->result));
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eh_action = scmd->device->host->eh_action;
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if (eh_action)
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complete(eh_action);
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}
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|
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/**
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* scsi_try_host_reset - ask host adapter to reset itself
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* @scmd: SCSI cmd to send hsot reset.
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*/
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static int scsi_try_host_reset(struct scsi_cmnd *scmd)
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{
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unsigned long flags;
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int rtn;
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SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n",
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__func__));
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if (!scmd->device->host->hostt->eh_host_reset_handler)
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return FAILED;
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rtn = scmd->device->host->hostt->eh_host_reset_handler(scmd);
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|
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if (rtn == SUCCESS) {
|
|
if (!scmd->device->host->hostt->skip_settle_delay)
|
|
ssleep(HOST_RESET_SETTLE_TIME);
|
|
spin_lock_irqsave(scmd->device->host->host_lock, flags);
|
|
scsi_report_bus_reset(scmd->device->host,
|
|
scmd_channel(scmd));
|
|
spin_unlock_irqrestore(scmd->device->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 int scsi_try_bus_reset(struct scsi_cmnd *scmd)
|
|
{
|
|
unsigned long flags;
|
|
int rtn;
|
|
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n",
|
|
__func__));
|
|
|
|
if (!scmd->device->host->hostt->eh_bus_reset_handler)
|
|
return FAILED;
|
|
|
|
rtn = scmd->device->host->hostt->eh_bus_reset_handler(scmd);
|
|
|
|
if (rtn == SUCCESS) {
|
|
if (!scmd->device->host->hostt->skip_settle_delay)
|
|
ssleep(BUS_RESET_SETTLE_TIME);
|
|
spin_lock_irqsave(scmd->device->host->host_lock, flags);
|
|
scsi_report_bus_reset(scmd->device->host,
|
|
scmd_channel(scmd));
|
|
spin_unlock_irqrestore(scmd->device->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 int scsi_try_target_reset(struct scsi_cmnd *scmd)
|
|
{
|
|
unsigned long flags;
|
|
int rtn;
|
|
|
|
if (!scmd->device->host->hostt->eh_target_reset_handler)
|
|
return FAILED;
|
|
|
|
rtn = scmd->device->host->hostt->eh_target_reset_handler(scmd);
|
|
if (rtn == SUCCESS) {
|
|
spin_lock_irqsave(scmd->device->host->host_lock, flags);
|
|
__starget_for_each_device(scsi_target(scmd->device), NULL,
|
|
__scsi_report_device_reset);
|
|
spin_unlock_irqrestore(scmd->device->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 int scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
|
|
{
|
|
int rtn;
|
|
|
|
if (!scmd->device->host->hostt->eh_device_reset_handler)
|
|
return FAILED;
|
|
|
|
rtn = scmd->device->host->hostt->eh_device_reset_handler(scmd);
|
|
if (rtn == SUCCESS)
|
|
__scsi_report_device_reset(scmd->device, NULL);
|
|
return rtn;
|
|
}
|
|
|
|
static int __scsi_try_to_abort_cmd(struct scsi_cmnd *scmd)
|
|
{
|
|
if (!scmd->device->host->hostt->eh_abort_handler)
|
|
return FAILED;
|
|
|
|
return scmd->device->host->hostt->eh_abort_handler(scmd);
|
|
}
|
|
|
|
/**
|
|
* scsi_try_to_abort_cmd - Ask host to abort a running command.
|
|
* @scmd: SCSI cmd to abort from Lower Level.
|
|
*
|
|
* Notes:
|
|
* This function will not return until the user's completion function
|
|
* has been called. there is no timeout on this operation. if the
|
|
* author of the low-level driver wishes this operation to be timed,
|
|
* they can provide this facility themselves. helper functions in
|
|
* scsi_error.c can be supplied to make this easier to do.
|
|
*/
|
|
static int scsi_try_to_abort_cmd(struct scsi_cmnd *scmd)
|
|
{
|
|
/*
|
|
* scsi_done was called just after the command timed out and before
|
|
* we had a chance to process it. (db)
|
|
*/
|
|
if (scmd->serial_number == 0)
|
|
return SUCCESS;
|
|
return __scsi_try_to_abort_cmd(scmd);
|
|
}
|
|
|
|
static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd)
|
|
{
|
|
if (__scsi_try_to_abort_cmd(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 recory
|
|
* @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 <= BLK_MAX_CDB)
|
|
* @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->cmnd = scmd->cmnd;
|
|
ses->data_direction = scmd->sc_data_direction;
|
|
ses->sdb = scmd->sdb;
|
|
ses->next_rq = scmd->request->next_rq;
|
|
ses->result = scmd->result;
|
|
ses->underflow = scmd->underflow;
|
|
ses->prot_op = scmd->prot_op;
|
|
|
|
scmd->prot_op = SCSI_PROT_NORMAL;
|
|
scmd->cmnd = ses->eh_cmnd;
|
|
memset(scmd->cmnd, 0, BLK_MAX_CDB);
|
|
memset(&scmd->sdb, 0, sizeof(scmd->sdb));
|
|
scmd->request->next_rq = NULL;
|
|
|
|
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 = 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 > BLK_MAX_CDB);
|
|
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 recory
|
|
* @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;
|
|
scmd->cmnd = ses->cmnd;
|
|
scmd->sc_data_direction = ses->data_direction;
|
|
scmd->sdb = ses->sdb;
|
|
scmd->request->next_rq = ses->next_rq;
|
|
scmd->result = ses->result;
|
|
scmd->underflow = ses->underflow;
|
|
scmd->prot_op = ses->prot_op;
|
|
}
|
|
EXPORT_SYMBOL(scsi_eh_restore_cmnd);
|
|
|
|
/**
|
|
* scsi_send_eh_cmnd - submit a scsi command as part of error recory
|
|
* @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 int 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;
|
|
unsigned long flags;
|
|
struct scsi_eh_save ses;
|
|
int rtn;
|
|
|
|
scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);
|
|
shost->eh_action = &done;
|
|
|
|
spin_lock_irqsave(shost->host_lock, flags);
|
|
scsi_log_send(scmd);
|
|
shost->hostt->queuecommand(scmd, scsi_eh_done);
|
|
spin_unlock_irqrestore(shost->host_lock, flags);
|
|
|
|
timeleft = wait_for_completion_timeout(&done, timeout);
|
|
|
|
shost->eh_action = NULL;
|
|
|
|
scsi_log_completion(scmd, SUCCESS);
|
|
|
|
SCSI_LOG_ERROR_RECOVERY(3,
|
|
printk("%s: scmd: %p, timeleft: %ld\n",
|
|
__func__, scmd, 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 tell the host to forget
|
|
* about this command.
|
|
*/
|
|
if (timeleft) {
|
|
rtn = scsi_eh_completed_normally(scmd);
|
|
SCSI_LOG_ERROR_RECOVERY(3,
|
|
printk("%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 {
|
|
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 int scsi_request_sense(struct scsi_cmnd *scmd)
|
|
{
|
|
return scsi_send_eh_cmnd(scmd, NULL, 0, SENSE_TIMEOUT, ~0);
|
|
}
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
scmd->device->host->host_failed--;
|
|
scmd->eh_eflags = 0;
|
|
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;
|
|
int rtn;
|
|
|
|
list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
|
|
if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) ||
|
|
SCSI_SENSE_VALID(scmd))
|
|
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, printk("sense requested for %p"
|
|
" result %x\n", scmd,
|
|
scmd->result));
|
|
SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", 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 */
|
|
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, rtn;
|
|
|
|
retry_tur:
|
|
rtn = scsi_send_eh_cmnd(scmd, tur_command, 6, SENSE_TIMEOUT, 0);
|
|
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n",
|
|
__func__, scmd, rtn));
|
|
|
|
switch (rtn) {
|
|
case NEEDS_RETRY:
|
|
if (retry_cnt--)
|
|
goto retry_tur;
|
|
/*FALLTHRU*/
|
|
case SUCCESS:
|
|
return 0;
|
|
default:
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* scsi_eh_abort_cmds - abort pending commands.
|
|
* @work_q: &list_head for pending commands.
|
|
* @done_q: &list_head for processed commands.
|
|
*
|
|
* Decription:
|
|
* Try and see whether or not it makes sense to try and abort the
|
|
* running command. This only works out to be the case if we have one
|
|
* command that has timed out. If the command simply failed, it makes
|
|
* no sense to try and abort the command, since as far as the shost
|
|
* adapter is concerned, it isn't running.
|
|
*/
|
|
static int scsi_eh_abort_cmds(struct list_head *work_q,
|
|
struct list_head *done_q)
|
|
{
|
|
struct scsi_cmnd *scmd, *next;
|
|
int rtn;
|
|
|
|
list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
|
|
if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD))
|
|
continue;
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:"
|
|
"0x%p\n", current->comm,
|
|
scmd));
|
|
rtn = scsi_try_to_abort_cmd(scmd);
|
|
if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
|
|
scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD;
|
|
if (!scsi_device_online(scmd->device) ||
|
|
rtn == FAST_IO_FAIL ||
|
|
!scsi_eh_tur(scmd)) {
|
|
scsi_eh_finish_cmd(scmd, done_q);
|
|
}
|
|
|
|
} else
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting"
|
|
" cmd failed:"
|
|
"0x%p\n",
|
|
current->comm,
|
|
scmd));
|
|
}
|
|
|
|
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, rtn = NEEDS_RETRY;
|
|
|
|
for (i = 0; rtn == NEEDS_RETRY && i < 2; i++)
|
|
rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, scmd->device->request_queue->rq_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) {
|
|
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, printk("%s: Sending START_UNIT to sdev:"
|
|
" 0x%p\n", current->comm, sdev));
|
|
|
|
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_finish_cmd(scmd, done_q);
|
|
}
|
|
}
|
|
} else {
|
|
SCSI_LOG_ERROR_RECOVERY(3,
|
|
printk("%s: START_UNIT failed to sdev:"
|
|
" 0x%p\n", current->comm, sdev));
|
|
}
|
|
}
|
|
|
|
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;
|
|
int rtn;
|
|
|
|
shost_for_each_device(sdev, shost) {
|
|
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, printk("%s: Sending BDR sdev:"
|
|
" 0x%p\n", current->comm,
|
|
sdev));
|
|
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_finish_cmd(scmd,
|
|
done_q);
|
|
}
|
|
}
|
|
} else {
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR"
|
|
" failed sdev:"
|
|
"0x%p\n",
|
|
current->comm,
|
|
sdev));
|
|
}
|
|
}
|
|
|
|
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)
|
|
{
|
|
struct scsi_cmnd *scmd, *tgtr_scmd, *next;
|
|
unsigned int id = 0;
|
|
int rtn;
|
|
|
|
do {
|
|
tgtr_scmd = NULL;
|
|
list_for_each_entry(scmd, work_q, eh_entry) {
|
|
if (id == scmd_id(scmd)) {
|
|
tgtr_scmd = scmd;
|
|
break;
|
|
}
|
|
}
|
|
if (!tgtr_scmd) {
|
|
/* not one exactly equal; find the next highest */
|
|
list_for_each_entry(scmd, work_q, eh_entry) {
|
|
if (scmd_id(scmd) > id &&
|
|
(!tgtr_scmd ||
|
|
scmd_id(tgtr_scmd) > scmd_id(scmd)))
|
|
tgtr_scmd = scmd;
|
|
}
|
|
}
|
|
if (!tgtr_scmd)
|
|
/* no more commands, that's it */
|
|
break;
|
|
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending target reset "
|
|
"to target %d\n",
|
|
current->comm, id));
|
|
rtn = scsi_try_target_reset(tgtr_scmd);
|
|
if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
|
|
list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
|
|
if (id == scmd_id(scmd))
|
|
if (!scsi_device_online(scmd->device) ||
|
|
rtn == FAST_IO_FAIL ||
|
|
!scsi_eh_tur(tgtr_scmd))
|
|
scsi_eh_finish_cmd(scmd,
|
|
done_q);
|
|
}
|
|
} else
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Target reset"
|
|
" failed target: "
|
|
"%d\n",
|
|
current->comm, id));
|
|
id++;
|
|
} while(id != 0);
|
|
|
|
return list_empty(work_q);
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
unsigned int channel;
|
|
int 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++) {
|
|
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, printk("%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 (!scsi_device_online(scmd->device) ||
|
|
rtn == FAST_IO_FAIL ||
|
|
!scsi_eh_tur(scmd))
|
|
scsi_eh_finish_cmd(scmd,
|
|
done_q);
|
|
}
|
|
} else {
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST"
|
|
" failed chan: %d\n",
|
|
current->comm,
|
|
channel));
|
|
}
|
|
}
|
|
return list_empty(work_q);
|
|
}
|
|
|
|
/**
|
|
* scsi_eh_host_reset - send a host reset
|
|
* @work_q: list_head for processed commands.
|
|
* @done_q: list_head for processed commands.
|
|
*/
|
|
static int scsi_eh_host_reset(struct list_head *work_q,
|
|
struct list_head *done_q)
|
|
{
|
|
struct scsi_cmnd *scmd, *next;
|
|
int rtn;
|
|
|
|
if (!list_empty(work_q)) {
|
|
scmd = list_entry(work_q->next,
|
|
struct scsi_cmnd, eh_entry);
|
|
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n"
|
|
, current->comm));
|
|
|
|
rtn = scsi_try_host_reset(scmd);
|
|
if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
|
|
list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
|
|
if (!scsi_device_online(scmd->device) ||
|
|
rtn == FAST_IO_FAIL ||
|
|
(!scsi_eh_try_stu(scmd) && !scsi_eh_tur(scmd)) ||
|
|
!scsi_eh_tur(scmd))
|
|
scsi_eh_finish_cmd(scmd, done_q);
|
|
}
|
|
} else {
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST"
|
|
" failed\n",
|
|
current->comm));
|
|
}
|
|
}
|
|
return list_empty(work_q);
|
|
}
|
|
|
|
/**
|
|
* scsi_eh_offline_sdevs - offline scsi devices that fail to recover
|
|
* @work_q: list_head for processed 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;
|
|
|
|
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");
|
|
scsi_device_set_state(scmd->device, SDEV_OFFLINE);
|
|
if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) {
|
|
/*
|
|
* FIXME: Handle lost cmds.
|
|
*/
|
|
}
|
|
scsi_eh_finish_cmd(scmd, done_q);
|
|
}
|
|
return;
|
|
}
|
|
|
|
/**
|
|
* scsi_noretry_cmd - determinte if command should be failed fast
|
|
* @scmd: SCSI cmd to examine.
|
|
*/
|
|
int scsi_noretry_cmd(struct scsi_cmnd *scmd)
|
|
{
|
|
switch (host_byte(scmd->result)) {
|
|
case DID_OK:
|
|
break;
|
|
case DID_BUS_BUSY:
|
|
return blk_failfast_transport(scmd->request);
|
|
case DID_PARITY:
|
|
return blk_failfast_dev(scmd->request);
|
|
case DID_ERROR:
|
|
if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
|
|
status_byte(scmd->result) == RESERVATION_CONFLICT)
|
|
return 0;
|
|
/* fall through */
|
|
case DID_SOFT_ERROR:
|
|
return blk_failfast_driver(scmd->request);
|
|
}
|
|
|
|
switch (status_byte(scmd->result)) {
|
|
case CHECK_CONDITION:
|
|
/*
|
|
* assume caller has checked sense and determinted
|
|
* the check condition was retryable.
|
|
*/
|
|
return blk_failfast_dev(scmd->request);
|
|
}
|
|
|
|
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.
|
|
*/
|
|
int scsi_decide_disposition(struct scsi_cmnd *scmd)
|
|
{
|
|
int 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, printk("%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_NO_CONNECT:
|
|
case DID_BAD_TARGET:
|
|
case DID_ABORT:
|
|
/*
|
|
* 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;
|
|
/*
|
|
* 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)
|
|
*
|
|
* actually this is a bug in this function here. we should
|
|
* be mindful of the maximum number of retries specified
|
|
* and not get stuck in a loop.
|
|
*/
|
|
case DID_SOFT_ERROR:
|
|
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_ERROR:
|
|
if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
|
|
status_byte(scmd->result) == 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;
|
|
}
|
|
|
|
/*
|
|
* next, check the message byte.
|
|
*/
|
|
if (msg_byte(scmd->result) != COMMAND_COMPLETE)
|
|
return FAILED;
|
|
|
|
/*
|
|
* check the status byte to see if this indicates anything special.
|
|
*/
|
|
switch (status_byte(scmd->result)) {
|
|
case QUEUE_FULL:
|
|
scsi_handle_queue_full(scmd->device);
|
|
/*
|
|
* the case of trying to send too many commands to a
|
|
* tagged queueing device.
|
|
*/
|
|
case 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 GOOD:
|
|
scsi_handle_queue_ramp_up(scmd->device);
|
|
case COMMAND_TERMINATED:
|
|
return SUCCESS;
|
|
case TASK_ABORTED:
|
|
goto maybe_retry;
|
|
case 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 CONDITION_GOOD:
|
|
case INTERMEDIATE_GOOD:
|
|
case INTERMEDIATE_C_GOOD:
|
|
case ACA_ACTIVE:
|
|
/*
|
|
* who knows? FIXME(eric)
|
|
*/
|
|
return SUCCESS;
|
|
|
|
case RESERVATION_CONFLICT:
|
|
sdev_printk(KERN_INFO, scmd->device,
|
|
"reservation conflict\n");
|
|
return SUCCESS; /* causes immediate i/o error */
|
|
default:
|
|
return FAILED;
|
|
}
|
|
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 ((++scmd->retries) <= scmd->allowed
|
|
&& !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, int uptodate)
|
|
{
|
|
__blk_put_request(req->q, 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 request *req;
|
|
|
|
/*
|
|
* blk_get_request with GFP_KERNEL (__GFP_WAIT) sleeps until a
|
|
* request becomes available
|
|
*/
|
|
req = blk_get_request(sdev->request_queue, READ, GFP_KERNEL);
|
|
|
|
req->cmd[0] = ALLOW_MEDIUM_REMOVAL;
|
|
req->cmd[1] = 0;
|
|
req->cmd[2] = 0;
|
|
req->cmd[3] = 0;
|
|
req->cmd[4] = SCSI_REMOVAL_PREVENT;
|
|
req->cmd[5] = 0;
|
|
|
|
req->cmd_len = COMMAND_SIZE(req->cmd[0]);
|
|
|
|
req->cmd_type = REQ_TYPE_BLOCK_PC;
|
|
req->cmd_flags |= REQ_QUIET;
|
|
req->timeout = 10 * HZ;
|
|
req->retries = 5;
|
|
|
|
blk_execute_rq_nowait(req->q, NULL, req, 1, eh_lock_door_done);
|
|
}
|
|
|
|
/**
|
|
* 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->locked)
|
|
scsi_eh_lock_door(sdev);
|
|
}
|
|
|
|
/*
|
|
* 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, printk("%s: waking up host to restart\n",
|
|
__func__));
|
|
|
|
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);
|
|
}
|
|
|
|
/**
|
|
* 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(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) &&
|
|
(++scmd->retries <= scmd->allowed)) {
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush"
|
|
" retry cmd: %p\n",
|
|
current->comm,
|
|
scmd));
|
|
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 DRIVER_TIMEOUT.
|
|
*/
|
|
if (!scmd->result)
|
|
scmd->result |= (DRIVER_TIMEOUT << 24);
|
|
SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish"
|
|
" cmd: %p\n",
|
|
current->comm, scmd));
|
|
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))
|
|
if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q))
|
|
scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
|
|
|
|
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.
|
|
*/
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
while (!kthread_should_stop()) {
|
|
if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
|
|
shost->host_failed != shost->host_busy) {
|
|
SCSI_LOG_ERROR_RECOVERY(1,
|
|
printk("Error handler scsi_eh_%d sleeping\n",
|
|
shost->host_no));
|
|
schedule();
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
continue;
|
|
}
|
|
|
|
__set_current_state(TASK_RUNNING);
|
|
SCSI_LOG_ERROR_RECOVERY(1,
|
|
printk("Error handler scsi_eh_%d waking up\n",
|
|
shost->host_no));
|
|
|
|
/*
|
|
* 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->transportt->eh_strategy_handler)
|
|
shost->transportt->eh_strategy_handler(shost);
|
|
else
|
|
scsi_unjam_host(shost);
|
|
|
|
/*
|
|
* 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);
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
}
|
|
__set_current_state(TASK_RUNNING);
|
|
|
|
SCSI_LOG_ERROR_RECOVERY(1,
|
|
printk("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);
|
|
|
|
static void
|
|
scsi_reset_provider_done_command(struct scsi_cmnd *scmd)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* Function: scsi_reset_provider
|
|
*
|
|
* Purpose: Send requested reset to a bus or device at any phase.
|
|
*
|
|
* Arguments: device - device to send reset to
|
|
* flag - reset type (see scsi.h)
|
|
*
|
|
* Returns: SUCCESS/FAILURE.
|
|
*
|
|
* Notes: This is used by the SCSI Generic driver to provide
|
|
* Bus/Device reset capability.
|
|
*/
|
|
int
|
|
scsi_reset_provider(struct scsi_device *dev, int flag)
|
|
{
|
|
struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL);
|
|
struct Scsi_Host *shost = dev->host;
|
|
struct request req;
|
|
unsigned long flags;
|
|
int rtn;
|
|
|
|
blk_rq_init(NULL, &req);
|
|
scmd->request = &req;
|
|
|
|
scmd->cmnd = req.cmd;
|
|
|
|
scmd->scsi_done = scsi_reset_provider_done_command;
|
|
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 (flag) {
|
|
case SCSI_TRY_RESET_DEVICE:
|
|
rtn = scsi_try_bus_device_reset(scmd);
|
|
if (rtn == SUCCESS)
|
|
break;
|
|
/* FALLTHROUGH */
|
|
case SCSI_TRY_RESET_TARGET:
|
|
rtn = scsi_try_target_reset(scmd);
|
|
if (rtn == SUCCESS)
|
|
break;
|
|
/* FALLTHROUGH */
|
|
case SCSI_TRY_RESET_BUS:
|
|
rtn = scsi_try_bus_reset(scmd);
|
|
if (rtn == SUCCESS)
|
|
break;
|
|
/* FALLTHROUGH */
|
|
case SCSI_TRY_RESET_HOST:
|
|
rtn = scsi_try_host_reset(scmd);
|
|
break;
|
|
default:
|
|
rtn = FAILED;
|
|
}
|
|
|
|
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,
|
|
printk("%s: waking up host to restart after TMF\n",
|
|
__func__));
|
|
|
|
wake_up(&shost->host_wait);
|
|
|
|
scsi_run_host_queues(shost);
|
|
|
|
scsi_next_command(scmd);
|
|
return rtn;
|
|
}
|
|
EXPORT_SYMBOL(scsi_reset_provider);
|
|
|
|
/**
|
|
* scsi_normalize_sense - normalize main elements from either fixed or
|
|
* descriptor sense data format into a common format.
|
|
*
|
|
* @sense_buffer: byte array containing sense data returned by device
|
|
* @sb_len: number of valid bytes in sense_buffer
|
|
* @sshdr: pointer to instance of structure that common
|
|
* elements are written to.
|
|
*
|
|
* Notes:
|
|
* The "main elements" from sense data are: response_code, sense_key,
|
|
* asc, ascq and additional_length (only for descriptor format).
|
|
*
|
|
* Typically this function can be called after a device has
|
|
* responded to a SCSI command with the CHECK_CONDITION status.
|
|
*
|
|
* Return value:
|
|
* 1 if valid sense data information found, else 0;
|
|
*/
|
|
int scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
|
|
struct scsi_sense_hdr *sshdr)
|
|
{
|
|
if (!sense_buffer || !sb_len)
|
|
return 0;
|
|
|
|
memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
|
|
|
|
sshdr->response_code = (sense_buffer[0] & 0x7f);
|
|
|
|
if (!scsi_sense_valid(sshdr))
|
|
return 0;
|
|
|
|
if (sshdr->response_code >= 0x72) {
|
|
/*
|
|
* descriptor format
|
|
*/
|
|
if (sb_len > 1)
|
|
sshdr->sense_key = (sense_buffer[1] & 0xf);
|
|
if (sb_len > 2)
|
|
sshdr->asc = sense_buffer[2];
|
|
if (sb_len > 3)
|
|
sshdr->ascq = sense_buffer[3];
|
|
if (sb_len > 7)
|
|
sshdr->additional_length = sense_buffer[7];
|
|
} else {
|
|
/*
|
|
* fixed format
|
|
*/
|
|
if (sb_len > 2)
|
|
sshdr->sense_key = (sense_buffer[2] & 0xf);
|
|
if (sb_len > 7) {
|
|
sb_len = (sb_len < (sense_buffer[7] + 8)) ?
|
|
sb_len : (sense_buffer[7] + 8);
|
|
if (sb_len > 12)
|
|
sshdr->asc = sense_buffer[12];
|
|
if (sb_len > 13)
|
|
sshdr->ascq = sense_buffer[13];
|
|
}
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
EXPORT_SYMBOL(scsi_normalize_sense);
|
|
|
|
int scsi_command_normalize_sense(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_sense_desc_find - search for a given descriptor type in descriptor sense data format.
|
|
* @sense_buffer: byte array of descriptor format sense data
|
|
* @sb_len: number of valid bytes in sense_buffer
|
|
* @desc_type: value of descriptor type to find
|
|
* (e.g. 0 -> information)
|
|
*
|
|
* Notes:
|
|
* only valid when sense data is in descriptor format
|
|
*
|
|
* Return value:
|
|
* pointer to start of (first) descriptor if found else NULL
|
|
*/
|
|
const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len,
|
|
int desc_type)
|
|
{
|
|
int add_sen_len, add_len, desc_len, k;
|
|
const u8 * descp;
|
|
|
|
if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7])))
|
|
return NULL;
|
|
if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73))
|
|
return NULL;
|
|
add_sen_len = (add_sen_len < (sb_len - 8)) ?
|
|
add_sen_len : (sb_len - 8);
|
|
descp = &sense_buffer[8];
|
|
for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) {
|
|
descp += desc_len;
|
|
add_len = (k < (add_sen_len - 1)) ? descp[1]: -1;
|
|
desc_len = add_len + 2;
|
|
if (descp[0] == desc_type)
|
|
return descp;
|
|
if (add_len < 0) // short descriptor ??
|
|
break;
|
|
}
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(scsi_sense_desc_find);
|
|
|
|
/**
|
|
* 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:
|
|
* 1 if information field found, 0 if not found.
|
|
*/
|
|
int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len,
|
|
u64 * info_out)
|
|
{
|
|
int j;
|
|
const u8 * ucp;
|
|
u64 ull;
|
|
|
|
if (sb_len < 7)
|
|
return 0;
|
|
switch (sense_buffer[0] & 0x7f) {
|
|
case 0x70:
|
|
case 0x71:
|
|
if (sense_buffer[0] & 0x80) {
|
|
*info_out = (sense_buffer[3] << 24) +
|
|
(sense_buffer[4] << 16) +
|
|
(sense_buffer[5] << 8) + sense_buffer[6];
|
|
return 1;
|
|
} else
|
|
return 0;
|
|
case 0x72:
|
|
case 0x73:
|
|
ucp = scsi_sense_desc_find(sense_buffer, sb_len,
|
|
0 /* info desc */);
|
|
if (ucp && (0xa == ucp[1])) {
|
|
ull = 0;
|
|
for (j = 0; j < 8; ++j) {
|
|
if (j > 0)
|
|
ull <<= 8;
|
|
ull |= ucp[4 + j];
|
|
}
|
|
*info_out = ull;
|
|
return 1;
|
|
} else
|
|
return 0;
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(scsi_get_sense_info_fld);
|
|
|
|
/**
|
|
* scsi_build_sense_buffer - build sense data in a buffer
|
|
* @desc: Sense format (non zero == descriptor format,
|
|
* 0 == fixed format)
|
|
* @buf: Where to build sense data
|
|
* @key: Sense key
|
|
* @asc: Additional sense code
|
|
* @ascq: Additional sense code qualifier
|
|
*
|
|
**/
|
|
void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq)
|
|
{
|
|
if (desc) {
|
|
buf[0] = 0x72; /* descriptor, current */
|
|
buf[1] = key;
|
|
buf[2] = asc;
|
|
buf[3] = ascq;
|
|
buf[7] = 0;
|
|
} else {
|
|
buf[0] = 0x70; /* fixed, current */
|
|
buf[2] = key;
|
|
buf[7] = 0xa;
|
|
buf[12] = asc;
|
|
buf[13] = ascq;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(scsi_build_sense_buffer);
|