scsi_obsolete.c

基于组件方式开发操作系统的OSKIT源代码

	    /* Failed to obtain sense information */
	{
	    SCpnt->flags &= ~WAS_SENSE;
#if 0	/* This cannot possibly be correct. */
	    SCpnt->internal_timeout &= ~SENSE_TIMEOUT;
#endif

	    if (!(SCpnt->flags & WAS_RESET))
	    {
		printk("scsi%d : channel %d target %d lun %d request sense"
		       " failed, performing reset.\n",
		       SCpnt->host->host_no, SCpnt->channel, SCpnt->target,
		       SCpnt->lun);
		scsi_reset(SCpnt, SCSI_RESET_SYNCHRONOUS);
		status = REDO;
                break;
	    }
	    else
	    {
		exit = (DRIVER_HARD | SUGGEST_ABORT);
		status = CMD_FINISHED;
	    }
	}
	else switch(msg_byte(result))
	{
	case COMMAND_COMPLETE:
	    switch (status_byte(result))
	    {
	    case GOOD:
		if (SCpnt->flags & WAS_SENSE)
		{
#ifdef DEBUG
		    printk ("In scsi_done, GOOD status, COMMAND COMPLETE, "
                            "parsing sense information.\n");
#endif
		    SCpnt->flags &= ~WAS_SENSE;
#if 0	/* This cannot possibly be correct. */
		    SCpnt->internal_timeout &= ~SENSE_TIMEOUT;
#endif

		    switch (checked = check_sense(SCpnt))
		    {
		    case SUGGEST_SENSE:
		    case 0:
#ifdef DEBUG
			printk("NO SENSE.  status = REDO\n");
#endif
			update_timeout(SCpnt, oldto);
			status = REDO;
			break;
		    case SUGGEST_IS_OK:
			break;
		    case SUGGEST_REMAP:
#ifdef DEBUG
			printk("SENSE SUGGEST REMAP - status = CMD_FINISHED\n");
#endif
			status = CMD_FINISHED;
			exit = DRIVER_SENSE | SUGGEST_ABORT;
			break;
		    case SUGGEST_RETRY:
#ifdef DEBUG
			printk("SENSE SUGGEST RETRY - status = MAYREDO\n");
#endif
			status = MAYREDO;
			exit = DRIVER_SENSE | SUGGEST_RETRY;
			break;
		    case SUGGEST_ABORT:
#ifdef DEBUG
			printk("SENSE SUGGEST ABORT - status = CMD_FINISHED");
#endif
			status = CMD_FINISHED;
			exit =  DRIVER_SENSE | SUGGEST_ABORT;
			break;
		    default:
			printk ("Internal error %s %d \n", __FILE__,
				__LINE__);
		    }
		} /* end WAS_SENSE */
		else
		{
#ifdef DEBUG
		    printk("COMMAND COMPLETE message returned, "
                           "status = CMD_FINISHED. \n");
#endif
		    exit =  DRIVER_OK;
		    status = CMD_FINISHED;
		}
		break;

	    case CHECK_CONDITION:
	    case COMMAND_TERMINATED:
		switch (check_sense(SCpnt))
		{
		case 0:
		    update_timeout(SCpnt, oldto);
		    status = REDO;
		    break;
		case SUGGEST_REMAP:
		    status = CMD_FINISHED;
		    exit =  DRIVER_SENSE | SUGGEST_ABORT;
		    break;
		case SUGGEST_RETRY:
		    status = MAYREDO;
		    exit = DRIVER_SENSE | SUGGEST_RETRY;
		    break;
		case SUGGEST_ABORT:
		    status = CMD_FINISHED;
		    exit =  DRIVER_SENSE | SUGGEST_ABORT;
		    break;
		case SUGGEST_SENSE:
		    scsi_request_sense (SCpnt);
		    status = PENDING;
		    break;
		}
		break;

	    case CONDITION_GOOD:
	    case INTERMEDIATE_GOOD:
	    case INTERMEDIATE_C_GOOD:
		break;

	    case BUSY:
	    case QUEUE_FULL:
		update_timeout(SCpnt, oldto);
		status = REDO;
		break;

	    case RESERVATION_CONFLICT:
		printk("scsi%d, channel %d : RESERVATION CONFLICT performing"
		       " reset.\n", SCpnt->host->host_no, SCpnt->channel);
                scsi_reset(SCpnt, SCSI_RESET_SYNCHRONOUS);
		status = REDO;
		break;
	    default:
		printk ("Internal error %s %d \n"
			"status byte = %d \n", __FILE__,
			__LINE__, status_byte(result));

	    }
	    break;
	default:
	    panic("scsi: unsupported message byte %d received\n",
		  msg_byte(result));
	}
	break;
    case DID_TIME_OUT:
#ifdef DEBUG
	printk("Host returned DID_TIME_OUT - ");
#endif

	if (SCpnt->flags & WAS_TIMEDOUT)
	{
#ifdef DEBUG
	    printk("Aborting\n");
#endif
	    /*
	      Allow TEST_UNIT_READY and INQUIRY commands to timeout early
	      without causing resets.  All other commands should be retried.
	    */
	    if (SCpnt->cmnd[0] != TEST_UNIT_READY &&
		SCpnt->cmnd[0] != INQUIRY)
		    status = MAYREDO;
	    exit = (DRIVER_TIMEOUT | SUGGEST_ABORT);
	}
	else
	{
#ifdef DEBUG
	    printk ("Retrying.\n");
#endif
	    SCpnt->flags  |= WAS_TIMEDOUT;
	    SCpnt->internal_timeout &= ~IN_ABORT;
	    status = REDO;
	}
	break;
    case DID_BUS_BUSY:
    case DID_PARITY:
	status = REDO;
	break;
    case DID_NO_CONNECT:
#ifdef DEBUG
	printk("Couldn't connect.\n");
#endif
	exit  = (DRIVER_HARD | SUGGEST_ABORT);
	break;
    case DID_ERROR:
	status = MAYREDO;
	exit = (DRIVER_HARD | SUGGEST_ABORT);
	break;
    case DID_BAD_TARGET:
    case DID_ABORT:
	exit = (DRIVER_INVALID | SUGGEST_ABORT);
	break;
    case DID_RESET:
	if (SCpnt->flags & IS_RESETTING)
	{
	    SCpnt->flags &= ~IS_RESETTING;
	    status = REDO;
	    break;
	}

	if(msg_byte(result) == GOOD &&
	   status_byte(result) == CHECK_CONDITION) {
	    switch (check_sense(SCpnt)) {
	    case 0:
		update_timeout(SCpnt, oldto);
		status = REDO;
		break;
	    case SUGGEST_REMAP:
	    case SUGGEST_RETRY:
		status = MAYREDO;
		exit = DRIVER_SENSE | SUGGEST_RETRY;
		break;
	    case SUGGEST_ABORT:
		status = CMD_FINISHED;
		exit =  DRIVER_SENSE | SUGGEST_ABORT;
		break;
	    case SUGGEST_SENSE:
		scsi_request_sense (SCpnt);
		status = PENDING;
		break;
	    }
	} else {
	    status=REDO;
	    exit = SUGGEST_RETRY;
	}
	break;
    default :
	exit = (DRIVER_ERROR | SUGGEST_DIE);
    }

    switch (status)
    {
    case CMD_FINISHED:
    case PENDING:
	break;
    case MAYREDO:
#ifdef DEBUG
	printk("In MAYREDO, allowing %d retries, have %d\n",
	       SCpnt->allowed, SCpnt->retries);
#endif
	if ((++SCpnt->retries) < SCpnt->allowed)
	{
	    if ((SCpnt->retries >= (SCpnt->allowed >> 1))
		&& !(SCpnt->host->resetting && time_before(jiffies, SCpnt->host->last_reset + MIN_RESET_PERIOD))
		&& !(SCpnt->flags & WAS_RESET))
	    {
		printk("scsi%d channel %d : resetting for second half of retries.\n",
		       SCpnt->host->host_no, SCpnt->channel);
		scsi_reset(SCpnt, SCSI_RESET_SYNCHRONOUS);
		/* fall through to REDO */
	    }
	}
	else
	{
	    status = CMD_FINISHED;
	    break;
	}
	/* fall through to REDO */

    case REDO:

	if (SCpnt->flags & WAS_SENSE)
	    scsi_request_sense(SCpnt);
	else
	{
	    memcpy ((void *) SCpnt->cmnd,
		    (void*) SCpnt->data_cmnd,
		    sizeof(SCpnt->data_cmnd));
            memset ((void *) SCpnt->sense_buffer, 0,
                    sizeof(SCpnt->sense_buffer));
	    SCpnt->request_buffer = SCpnt->buffer;
	    SCpnt->request_bufflen = SCpnt->bufflen;
	    SCpnt->use_sg = SCpnt->old_use_sg;
	    SCpnt->cmd_len = SCpnt->old_cmd_len;
            SCpnt->result = 0;
	    internal_cmnd (SCpnt);
	}
	break;
    default:
	INTERNAL_ERROR;
    }

    if (status == CMD_FINISHED) {
#ifdef DEBUG
	printk("Calling done function - at address %p\n", SCpnt->done);
#endif
	host->host_busy--; /* Indicate that we are free */

	if (host->block && host->host_busy == 0) {
	    host_active = NULL;

	    /* For block devices "wake_up" is done in end_scsi_request */
	    if (!SCSI_BLK_MAJOR(MAJOR(SCpnt->request.rq_dev))) {
		struct Scsi_Host * next;

		for (next = host->block; next != host; next = next->block)
		    wake_up(&next->host_wait);
	    }

	}

	wake_up(&host->host_wait);
	SCpnt->result = result | ((exit & 0xff) << 24);
	SCpnt->use_sg = SCpnt->old_use_sg;
	SCpnt->cmd_len = SCpnt->old_cmd_len;
	SCpnt->done (SCpnt);
    }

#undef CMD_FINISHED
#undef REDO
#undef MAYREDO
#undef PENDING
}

/*
 * The scsi_abort function interfaces with the abort() function of the host
 * we are aborting, and causes the current command to not complete.  The
 * caller should deal with any error messages or status returned on the
 * next call.
 *
 * This will not be called reentrantly for a given host.
 */

/*
 * Since we're nice guys and specified that abort() and reset()
 * can be non-reentrant.  The internal_timeout flags are used for
 * this.
 */


static int scsi_abort (Scsi_Cmnd * SCpnt, int why)
{
    int oldto;
    struct Scsi_Host * host = SCpnt->host;

    while(1)
    {

	/*
	 * Protect against races here.  If the command is done, or we are
	 * on a different command forget it.
	 */
	if (SCpnt->serial_number != SCpnt->serial_number_at_timeout) {
	    return 0;
	}

	if (SCpnt->internal_timeout & IN_ABORT)
	{
	    spin_unlock_irq(&io_request_lock);
	    while (SCpnt->internal_timeout & IN_ABORT)
		barrier();
	    spin_lock_irq(&io_request_lock);
	}
	else
	{
	    SCpnt->internal_timeout |= IN_ABORT;
	    oldto = update_timeout(SCpnt, ABORT_TIMEOUT);

	    if ((SCpnt->flags & IS_RESETTING) && SCpnt->device->soft_reset) {
		/* OK, this command must have died when we did the
		 *  reset.  The device itself must have lied.
		 */
		printk("Stale command on %d %d:%d appears to have died when"
		       " the bus was reset\n",
		       SCpnt->channel, SCpnt->target, SCpnt->lun);
	    }

	    if (!host->host_busy) {
		SCpnt->internal_timeout &= ~IN_ABORT;
		update_timeout(SCpnt, oldto);
		return 0;
	    }
	    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)) {