scsi_obsolete.c

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			}
			printk("scsi : aborting command due to timeout : pid %lu, scsi%d,"
			       " channel %d, id %d, lun %d ",
			       SCpnt->pid, SCpnt->host->host_no, (int) SCpnt->channel,
			       (int) SCpnt->target, (int) SCpnt->lun);
			print_command(SCpnt->cmnd);
			if (SCpnt->serial_number != SCpnt->serial_number_at_timeout)
				return 0;
			SCpnt->abort_reason = why;
			switch (host->hostt->abort(SCpnt)) {
				/* We do not know how to abort.  Try waiting another
				 * time increment and see if this helps. Set the
				 * WAS_TIMEDOUT flag set so we do not try this twice
				 */
			case SCSI_ABORT_BUSY:	/* Tough call - returning 1 from
						 * this is too severe
						 */
			case SCSI_ABORT_SNOOZE:
				if (why == DID_TIME_OUT) {
					SCpnt->internal_timeout &= ~IN_ABORT;
					if (SCpnt->flags & WAS_TIMEDOUT) {
						return 1;	/* Indicate we cannot handle this.
								 * We drop down into the reset handler
								 * and try again
								 */
					} else {
						SCpnt->flags |= WAS_TIMEDOUT;
						oldto = SCpnt->timeout_per_command;
						update_timeout(SCpnt, oldto);
					}
				}
				return 0;
			case SCSI_ABORT_PENDING:
				if (why != DID_TIME_OUT) {
					update_timeout(SCpnt, oldto);
				}
				return 0;
			case SCSI_ABORT_SUCCESS:
				/* We should have already aborted this one.  No
				 * need to adjust timeout
				 */
				SCpnt->internal_timeout &= ~IN_ABORT;
				return 0;
			case SCSI_ABORT_NOT_RUNNING:
				SCpnt->internal_timeout &= ~IN_ABORT;
				update_timeout(SCpnt, 0);
				return 0;
			case SCSI_ABORT_ERROR:
			default:
				SCpnt->internal_timeout &= ~IN_ABORT;
				return 1;
			}
		}
	}
}


/* Mark a single SCSI Device as having been reset. */

static inline void scsi_mark_device_reset(Scsi_Device * Device)
{
	Device->was_reset = 1;
	Device->expecting_cc_ua = 1;
}


/* Mark all SCSI Devices on a specific Host as having been reset. */

void scsi_mark_host_reset(struct Scsi_Host *Host)
{
	Scsi_Cmnd *SCpnt;
	Scsi_Device *SDpnt;

	for (SDpnt = Host->host_queue; SDpnt; SDpnt = SDpnt->next) {
		for (SCpnt = SDpnt->device_queue; SCpnt; SCpnt = SCpnt->next)
			scsi_mark_device_reset(SCpnt->device);
	}
}


/* Mark all SCSI Devices on a specific Host Bus as having been reset. */

static void scsi_mark_bus_reset(struct Scsi_Host *Host, int channel)
{
	Scsi_Cmnd *SCpnt;
	Scsi_Device *SDpnt;

	for (SDpnt = Host->host_queue; SDpnt; SDpnt = SDpnt->next) {
		for (SCpnt = SDpnt->device_queue; SCpnt; SCpnt = SCpnt->next)
			if (SCpnt->channel == channel)
				scsi_mark_device_reset(SCpnt->device);
	}
}


static int scsi_reset(Scsi_Cmnd * SCpnt, unsigned int reset_flags)
{
	int temp;
	Scsi_Cmnd *SCpnt1;
	Scsi_Device *SDpnt;
	struct Scsi_Host *host = SCpnt->host;

	printk("SCSI bus is being reset for host %d channel %d.\n",
	       host->host_no, SCpnt->channel);

#if 0
	/*
	 * First of all, we need to make a recommendation to the low-level
	 * driver as to whether a BUS_DEVICE_RESET should be performed,
	 * or whether we should do a full BUS_RESET.  There is no simple
	 * algorithm here - we basically use a series of heuristics
	 * to determine what we should do.
	 */
	SCpnt->host->suggest_bus_reset = FALSE;

	/*
	 * First see if all of the active devices on the bus have
	 * been jammed up so that we are attempting resets.  If so,
	 * then suggest a bus reset.  Forcing a bus reset could
	 * result in some race conditions, but no more than
	 * you would usually get with timeouts.  We will cross
	 * that bridge when we come to it.
	 *
	 * This is actually a pretty bad idea, since a sequence of
	 * commands will often timeout together and this will cause a
	 * Bus Device Reset followed immediately by a SCSI Bus Reset.
	 * If all of the active devices really are jammed up, the
	 * Bus Device Reset will quickly timeout and scsi_times_out
	 * will follow up with a SCSI Bus Reset anyway.
	 */
	SCpnt1 = host->host_queue;
	while (SCpnt1) {
		if (SCpnt1->request.rq_status != RQ_INACTIVE
		    && (SCpnt1->flags & (WAS_RESET | IS_RESETTING)) == 0)
			break;
		SCpnt1 = SCpnt1->next;
	}
	if (SCpnt1 == NULL) {
		reset_flags |= SCSI_RESET_SUGGEST_BUS_RESET;
	}
	/*
	 * If the code that called us is suggesting a hard reset, then
	 * definitely request it.  This usually occurs because a
	 * BUS_DEVICE_RESET times out.
	 *
	 * Passing reset_flags along takes care of this automatically.
	 */
	if (reset_flags & SCSI_RESET_SUGGEST_BUS_RESET) {
		SCpnt->host->suggest_bus_reset = TRUE;
	}
#endif

	while (1) {

		/*
		 * Protect against races here.  If the command is done, or we are
		 * on a different command forget it.
		 */
		if (reset_flags & SCSI_RESET_ASYNCHRONOUS)
			if (SCpnt->serial_number != SCpnt->serial_number_at_timeout) {
				return 0;
			}
		if (SCpnt->internal_timeout & IN_RESET) {
			spin_unlock_irq(&io_request_lock);
			while (SCpnt->internal_timeout & IN_RESET)
				barrier();
			spin_lock_irq(&io_request_lock);
		} else {
			SCpnt->internal_timeout |= IN_RESET;
			update_timeout(SCpnt, RESET_TIMEOUT);

			if (reset_flags & SCSI_RESET_SYNCHRONOUS)
				SCpnt->flags |= SYNC_RESET;
			if (host->host_busy) {
				for (SDpnt = host->host_queue; SDpnt; SDpnt = SDpnt->next) {
					SCpnt1 = SDpnt->device_queue;
					while (SCpnt1) {
						if (SCpnt1->request.rq_status != RQ_INACTIVE) {
#if 0
							if (!(SCpnt1->flags & IS_RESETTING) &&
							    !(SCpnt1->internal_timeout & IN_ABORT))
								scsi_abort(SCpnt1, DID_RESET);
#endif
							SCpnt1->flags |= (WAS_RESET | IS_RESETTING);
						}
						SCpnt1 = SCpnt1->next;
					}
				}

				host->last_reset = jiffies;
				host->resetting = 1;
				/*
				 * I suppose that the host reset callback will not play
				 * with the resetting field. We have just set the resetting
				 * flag here. -arca
				 */
				temp = host->hostt->reset(SCpnt, reset_flags);
				/*
				   This test allows the driver to introduce an additional bus
				   settle time delay by setting last_reset up to 20 seconds in
				   the future.  In the normal case where the driver does not
				   modify last_reset, it must be assumed that the actual bus
				   reset occurred immediately prior to the return to this code,
				   and so last_reset must be updated to the current time, so
				   that the delay in internal_cmnd will guarantee at least a
				   MIN_RESET_DELAY bus settle time.
				 */
				if (host->last_reset - jiffies > 20UL * HZ)
					host->last_reset = jiffies;
			} else {
				host->host_busy++;
				host->last_reset = jiffies;
				host->resetting = 1;
				SCpnt->flags |= (WAS_RESET | IS_RESETTING);
				/*
				 * I suppose that the host reset callback will not play
				 * with the resetting field. We have just set the resetting
				 * flag here. -arca
				 */
				temp = host->hostt->reset(SCpnt, reset_flags);
				if (time_before(host->last_reset, jiffies) ||
				    (time_after(host->last_reset, jiffies + 20 * HZ)))
					host->last_reset = jiffies;
				host->host_busy--;
			}
			if (reset_flags & SCSI_RESET_SYNCHRONOUS)
				SCpnt->flags &= ~SYNC_RESET;

#ifdef DEBUG
			printk("scsi reset function returned %d\n", temp);
#endif

			/*
			 * Now figure out what we need to do, based upon
			 * what the low level driver said that it did.
			 * If the result is SCSI_RESET_SUCCESS, SCSI_RESET_PENDING,
			 * or SCSI_RESET_WAKEUP, then the low level driver did a
			 * bus device reset or bus reset, so we should go through
			 * and mark one or all of the devices on that bus
			 * as having been reset.
			 */
			switch (temp & SCSI_RESET_ACTION) {
			case SCSI_RESET_SUCCESS:
				if (temp & SCSI_RESET_HOST_RESET)
					scsi_mark_host_reset(host);
				else if (temp & SCSI_RESET_BUS_RESET)
					scsi_mark_bus_reset(host, SCpnt->channel);
				else
					scsi_mark_device_reset(SCpnt->device);
				SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2 | IN_RESET3);
				return 0;
			case SCSI_RESET_PENDING:
				if (temp & SCSI_RESET_HOST_RESET)
					scsi_mark_host_reset(host);
				else if (temp & SCSI_RESET_BUS_RESET)
					scsi_mark_bus_reset(host, SCpnt->channel);
				else
					scsi_mark_device_reset(SCpnt->device);
			case SCSI_RESET_NOT_RUNNING:
				return 0;
			case SCSI_RESET_PUNT:
				SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2 | IN_RESET3);
				scsi_request_sense(SCpnt);
				return 0;
			case SCSI_RESET_WAKEUP:
				if (temp & SCSI_RESET_HOST_RESET)
					scsi_mark_host_reset(host);
				else if (temp & SCSI_RESET_BUS_RESET)
					scsi_mark_bus_reset(host, SCpnt->channel);
				else
					scsi_mark_device_reset(SCpnt->device);
				SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2 | IN_RESET3);
				scsi_request_sense(SCpnt);
				/*
				 * If a bus reset was performed, we
				 * need to wake up each and every command
				 * that was active on the bus or if it was a HBA
				 * reset all active commands on all channels
				 */
				if (temp & SCSI_RESET_HOST_RESET) {
					for (SDpnt = host->host_queue; SDpnt; SDpnt = SDpnt->next) {
						SCpnt1 = SDpnt->device_queue;
						while (SCpnt1) {
							if (SCpnt1->request.rq_status != RQ_INACTIVE
							    && SCpnt1 != SCpnt)
								scsi_request_sense(SCpnt1);
							SCpnt1 = SCpnt1->next;
						}
					}
				} else if (temp & SCSI_RESET_BUS_RESET) {
					for (SDpnt = host->host_queue; SDpnt; SDpnt = SDpnt->next) {
						SCpnt1 = SDpnt->device_queue;
						while (SCpnt1) {
							if (SCpnt1->request.rq_status != RQ_INACTIVE
							&& SCpnt1 != SCpnt
							    && SCpnt1->channel == SCpnt->channel)
								scsi_request_sense(SCpnt);
							SCpnt1 = SCpnt1->next;
						}
					}
				}
				return 0;
			case SCSI_RESET_SNOOZE:
				/* In this case, we set the timeout field to 0
				 * so that this command does not time out any more,
				 * and we return 1 so that we get a message on the
				 * screen.
				 */
				SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2 | IN_RESET3);
				update_timeout(SCpnt, 0);
				/* If you snooze, you lose... */
			case SCSI_RESET_ERROR:
			default:
				return 1;
			}

			return temp;
		}
	}
}

/*
 * The strategy is to cause the timer code to call scsi_times_out()
 * when the soonest timeout is pending.
 * The arguments are used when we are queueing a new command, because
 * we do not want to subtract the time used from this time, but when we
 * set the timer, we want to take this value into account.
 */

int update_timeout(Scsi_Cmnd * SCset, int timeout)
{
	int rtn;

	/*
	 * We are using the new error handling code to actually register/deregister
	 * timers for timeout.
	 */

	if (!timer_pending(&SCset->eh_timeout)) {
		rtn = 0;
	} else {
		rtn = SCset->eh_timeout.expires - jiffies;
	}

	if (timeout == 0) {
		scsi_delete_timer(SCset);
	} else {
		scsi_add_timer(SCset, timeout, scsi_old_times_out);
	}

	return rtn;
}


/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * Emacs will notice this stuff at the end of the file and automatically
 * adjust the settings for this buffer only.  This must remain at the end
 * of the file.
 * ---------------------------------------------------------------------------
 * Local variables:
 * c-indent-level: 4
 * c-brace-imaginary-offset: 0
 * c-brace-offset: -4
 * c-argdecl-indent: 4
 * c-label-offset: -4
 * c-continued-statement-offset: 4
 * c-continued-brace-offset: 0
 * indent-tabs-mode: nil
 * tab-width: 8
 * End:
 */