libata-scsi.c

linux 内核源代码

 *	current command.
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 *
 *	RETURNS:
 *	Command allocated, or %NULL if none available.
 */
static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
					      struct scsi_cmnd *cmd,
					      void (*done)(struct scsi_cmnd *))
{
	struct ata_queued_cmd *qc;

	qc = ata_qc_new_init(dev);
	if (qc) {
		qc->scsicmd = cmd;
		qc->scsidone = done;

		qc->__sg = scsi_sglist(cmd);
		qc->n_elem = scsi_sg_count(cmd);
	} else {
		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
		done(cmd);
	}

	return qc;
}

/**
 *	ata_dump_status - user friendly display of error info
 *	@id: id of the port in question
 *	@tf: ptr to filled out taskfile
 *
 *	Decode and dump the ATA error/status registers for the user so
 *	that they have some idea what really happened at the non
 *	make-believe layer.
 *
 *	LOCKING:
 *	inherited from caller
 */
static void ata_dump_status(unsigned id, struct ata_taskfile *tf)
{
	u8 stat = tf->command, err = tf->feature;

	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
	if (stat & ATA_BUSY) {
		printk("Busy }\n");	/* Data is not valid in this case */
	} else {
		if (stat & 0x40)	printk("DriveReady ");
		if (stat & 0x20)	printk("DeviceFault ");
		if (stat & 0x10)	printk("SeekComplete ");
		if (stat & 0x08)	printk("DataRequest ");
		if (stat & 0x04)	printk("CorrectedError ");
		if (stat & 0x02)	printk("Index ");
		if (stat & 0x01)	printk("Error ");
		printk("}\n");

		if (err) {
			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
			if (err & 0x04)		printk("DriveStatusError ");
			if (err & 0x80) {
				if (err & 0x04)	printk("BadCRC ");
				else		printk("Sector ");
			}
			if (err & 0x40)		printk("UncorrectableError ");
			if (err & 0x10)		printk("SectorIdNotFound ");
			if (err & 0x02)		printk("TrackZeroNotFound ");
			if (err & 0x01)		printk("AddrMarkNotFound ");
			printk("}\n");
		}
	}
}

/**
 *	ata_to_sense_error - convert ATA error to SCSI error
 *	@id: ATA device number
 *	@drv_stat: value contained in ATA status register
 *	@drv_err: value contained in ATA error register
 *	@sk: the sense key we'll fill out
 *	@asc: the additional sense code we'll fill out
 *	@ascq: the additional sense code qualifier we'll fill out
 *	@verbose: be verbose
 *
 *	Converts an ATA error into a SCSI error.  Fill out pointers to
 *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
 *	format sense blocks.
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 */
static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
			       u8 *asc, u8 *ascq, int verbose)
{
	int i;

	/* Based on the 3ware driver translation table */
	static const unsigned char sense_table[][4] = {
		/* BBD|ECC|ID|MAR */
		{0xd1, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
		/* BBD|ECC|ID */
		{0xd0,  	ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
		/* ECC|MC|MARK */
		{0x61, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Device fault                 Hardware error
		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
		{0x84, 		ABORTED_COMMAND, 0x47, 0x00}, 	// Data CRC error               SCSI parity error
		/* MC|ID|ABRT|TRK0|MARK */
		{0x37, 		NOT_READY, 0x04, 0x00}, 	// Unit offline                 Not ready
		/* MCR|MARK */
		{0x09, 		NOT_READY, 0x04, 0x00}, 	// Unrecovered disk error       Not ready
		/*  Bad address mark */
		{0x01, 		MEDIUM_ERROR, 0x13, 0x00}, 	// Address mark not found       Address mark not found for data field
		/* TRK0 */
		{0x02, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Track 0 not found		  Hardware error
		/* Abort & !ICRC */
		{0x04, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Aborted command              Aborted command
		/* Media change request */
		{0x08, 		NOT_READY, 0x04, 0x00}, 	// Media change request	  FIXME: faking offline
		/* SRV */
		{0x10, 		ABORTED_COMMAND, 0x14, 0x00}, 	// ID not found                 Recorded entity not found
		/* Media change */
		{0x08,  	NOT_READY, 0x04, 0x00}, 	// Media change		  FIXME: faking offline
		/* ECC */
		{0x40, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Uncorrectable ECC error      Unrecovered read error
		/* BBD - block marked bad */
		{0x80, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Block marked bad		  Medium error, unrecovered read error
		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
	};
	static const unsigned char stat_table[][4] = {
		/* Must be first because BUSY means no other bits valid */
		{0x80, 		ABORTED_COMMAND, 0x47, 0x00},	// Busy, fake parity for now
		{0x20, 		HARDWARE_ERROR,  0x00, 0x00}, 	// Device fault
		{0x08, 		ABORTED_COMMAND, 0x47, 0x00},	// Timed out in xfer, fake parity for now
		{0x04, 		RECOVERED_ERROR, 0x11, 0x00},	// Recovered ECC error	  Medium error, recovered
		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
	};

	/*
	 *	Is this an error we can process/parse
	 */
	if (drv_stat & ATA_BUSY) {
		drv_err = 0;	/* Ignore the err bits, they're invalid */
	}

	if (drv_err) {
		/* Look for drv_err */
		for (i = 0; sense_table[i][0] != 0xFF; i++) {
			/* Look for best matches first */
			if ((sense_table[i][0] & drv_err) ==
			    sense_table[i][0]) {
				*sk = sense_table[i][1];
				*asc = sense_table[i][2];
				*ascq = sense_table[i][3];
				goto translate_done;
			}
		}
		/* No immediate match */
		if (verbose)
			printk(KERN_WARNING "ata%u: no sense translation for "
			       "error 0x%02x\n", id, drv_err);
	}

	/* Fall back to interpreting status bits */
	for (i = 0; stat_table[i][0] != 0xFF; i++) {
		if (stat_table[i][0] & drv_stat) {
			*sk = stat_table[i][1];
			*asc = stat_table[i][2];
			*ascq = stat_table[i][3];
			goto translate_done;
		}
	}
	/* No error?  Undecoded? */
	if (verbose)
		printk(KERN_WARNING "ata%u: no sense translation for "
		       "status: 0x%02x\n", id, drv_stat);

	/* We need a sensible error return here, which is tricky, and one
	   that won't cause people to do things like return a disk wrongly */
	*sk = ABORTED_COMMAND;
	*asc = 0x00;
	*ascq = 0x00;

 translate_done:
	if (verbose)
		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
		       id, drv_stat, drv_err, *sk, *asc, *ascq);
	return;
}

/*
 *	ata_gen_passthru_sense - Generate check condition sense block.
 *	@qc: Command that completed.
 *
 *	This function is specific to the ATA descriptor format sense
 *	block specified for the ATA pass through commands.  Regardless
 *	of whether the command errored or not, return a sense
 *	block. Copy all controller registers into the sense
 *	block. Clear sense key, ASC & ASCQ if there is no error.
 *
 *	LOCKING:
 *	None.
 */
static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
{
	struct scsi_cmnd *cmd = qc->scsicmd;
	struct ata_taskfile *tf = &qc->result_tf;
	unsigned char *sb = cmd->sense_buffer;
	unsigned char *desc = sb + 8;
	int verbose = qc->ap->ops->error_handler == NULL;

	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);

	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;

	/*
	 * Use ata_to_sense_error() to map status register bits
	 * onto sense key, asc & ascq.
	 */
	if (qc->err_mask ||
	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
				   &sb[1], &sb[2], &sb[3], verbose);
		sb[1] &= 0x0f;
	}

	/*
	 * Sense data is current and format is descriptor.
	 */
	sb[0] = 0x72;

	desc[0] = 0x09;

	/* set length of additional sense data */
	sb[7] = 14;
	desc[1] = 12;

	/*
	 * Copy registers into sense buffer.
	 */
	desc[2] = 0x00;
	desc[3] = tf->feature;	/* == error reg */
	desc[5] = tf->nsect;
	desc[7] = tf->lbal;
	desc[9] = tf->lbam;
	desc[11] = tf->lbah;
	desc[12] = tf->device;
	desc[13] = tf->command; /* == status reg */

	/*
	 * Fill in Extend bit, and the high order bytes
	 * if applicable.
	 */
	if (tf->flags & ATA_TFLAG_LBA48) {
		desc[2] |= 0x01;
		desc[4] = tf->hob_nsect;
		desc[6] = tf->hob_lbal;
		desc[8] = tf->hob_lbam;
		desc[10] = tf->hob_lbah;
	}
}

/**
 *	ata_gen_ata_sense - generate a SCSI fixed sense block
 *	@qc: Command that we are erroring out
 *
 *	Generate sense block for a failed ATA command @qc.  Descriptor
 *	format is used to accomodate LBA48 block address.
 *
 *	LOCKING:
 *	None.
 */
static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
{
	struct ata_device *dev = qc->dev;
	struct scsi_cmnd *cmd = qc->scsicmd;
	struct ata_taskfile *tf = &qc->result_tf;
	unsigned char *sb = cmd->sense_buffer;
	unsigned char *desc = sb + 8;
	int verbose = qc->ap->ops->error_handler == NULL;
	u64 block;

	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);

	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;

	/* sense data is current and format is descriptor */
	sb[0] = 0x72;

	/* Use ata_to_sense_error() to map status register bits
	 * onto sense key, asc & ascq.
	 */
	if (qc->err_mask ||
	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
				   &sb[1], &sb[2], &sb[3], verbose);
		sb[1] &= 0x0f;
	}

	block = ata_tf_read_block(&qc->result_tf, dev);

	/* information sense data descriptor */
	sb[7] = 12;
	desc[0] = 0x00;
	desc[1] = 10;

	desc[2] |= 0x80;	/* valid */
	desc[6] = block >> 40;
	desc[7] = block >> 32;
	desc[8] = block >> 24;
	desc[9] = block >> 16;
	desc[10] = block >> 8;
	desc[11] = block;
}

static void ata_scsi_sdev_config(struct scsi_device *sdev)
{
	sdev->use_10_for_rw = 1;
	sdev->use_10_for_ms = 1;

	/* Schedule policy is determined by ->qc_defer() callback and
	 * it needs to see every deferred qc.  Set dev_blocked to 1 to
	 * prevent SCSI midlayer from automatically deferring
	 * requests.
	 */
	sdev->max_device_blocked = 1;
}

static void ata_scsi_dev_config(struct scsi_device *sdev,
				struct ata_device *dev)
{
	/* configure max sectors */
	blk_queue_max_sectors(sdev->request_queue, dev->max_sectors);

	/* SATA DMA transfers must be multiples of 4 byte, so
	 * we need to pad ATAPI transfers using an extra sg.
	 * Decrement max hw segments accordingly.
	 */
	if (dev->class == ATA_DEV_ATAPI) {
		struct request_queue *q = sdev->request_queue;
		blk_queue_max_hw_segments(q, q->max_hw_segments - 1);
	}

	if (dev->class == ATA_DEV_ATA)
		sdev->manage_start_stop = 1;

	if (dev->flags & ATA_DFLAG_AN)
		set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events);

	if (dev->flags & ATA_DFLAG_NCQ) {
		int depth;

		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
		depth = min(ATA_MAX_QUEUE - 1, depth);
		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
	}
}

/**
 *	ata_scsi_slave_config - Set SCSI device attributes
 *	@sdev: SCSI device to examine
 *
 *	This is called before we actually start reading
 *	and writing to the device, to configure certain
 *	SCSI mid-layer behaviors.
 *
 *	LOCKING:
 *	Defined by SCSI layer.  We don't really care.
 */

int ata_scsi_slave_config(struct scsi_device *sdev)
{
	struct ata_port *ap = ata_shost_to_port(sdev->host);
	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);

	ata_scsi_sdev_config(sdev);

	if (dev)
		ata_scsi_dev_config(sdev, dev);

	return 0;	/* scsi layer doesn't check return value, sigh */
}

/**
 *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
 *	@sdev: SCSI device to be destroyed
 *
 *	@sdev is about to be destroyed for hot/warm unplugging.  If
 *	this unplugging was initiated by libata as indicated by NULL
 *	dev->sdev, this function doesn't have to do anything.
 *	Otherwise, SCSI layer initiated warm-unplug is in progress.
 *	Clear dev->sdev, schedule the device for ATA detach and invoke
 *	EH.
 *
 *	LOCKING:
 *	Defined by SCSI layer.  We don't really care.
 */
void ata_scsi_slave_destroy(struct scsi_device *sdev)
{
	struct ata_port *ap = ata_shost_to_port(sdev->host);
	unsigned long flags;
	struct ata_device *dev;

	if (!ap->ops->error_handler)
		return;

	spin_lock_irqsave(ap->lock, flags);
	dev = __ata_scsi_find_dev(ap, sdev);
	if (dev && dev->sdev) {
		/* SCSI device already in CANCEL state, no need to offline it */
		dev->sdev = NULL;
		dev->flags |= ATA_DFLAG_DETACH;
		ata_port_schedule_eh(ap);
	}
	spin_unlock_irqrestore(ap->lock, flags);
}

/**
 *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
 *	@sdev: SCSI device to configure queue depth for
 *	@queue_depth: new queue depth
 *
 *	This is libata standard hostt->change_queue_depth callback.
 *	SCSI will call into this callback when user tries to set queue
 *	depth via sysfs.
 *
 *	LOCKING:
 *	SCSI layer (we don't care)
 *
 *	RETURNS:
 *	Newly configured queue depth.
 */
int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
{
	struct ata_port *ap = ata_shost_to_port(sdev->host);
	struct ata_device *dev;
	unsigned long flags;

	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
		return sdev->queue_depth;

	dev = ata_scsi_find_dev(ap, sdev);
	if (!dev || !ata_dev_enabled(dev))
		return sdev->queue_depth;

	/* NCQ enabled? */
	spin_lock_irqsave(ap->lock, flags);
	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
		dev->flags |= ATA_DFLAG_NCQ_OFF;
		queue_depth = 1;
	}
	spin_unlock_irqrestore(ap->lock, flags);

	/* limit and apply queue depth */
	queue_depth = min(queue_depth, sdev->host->can_queue);
	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);

	if (sdev->queue_depth == queue_depth)
		return -EINVAL;

	scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
	return queue_depth;
}

/* XXX: for spindown warning */
static void ata_delayed_done_timerfn(unsigned long arg)
{
	struct scsi_cmnd *scmd = (void *)arg;

	scmd->scsi_done(scmd);
}

/* XXX: for spindown warning */
static void ata_delayed_done(struct scsi_cmnd *scmd)
{
	static struct timer_list timer;

	setup_timer(&timer, ata_delayed_done_timerfn, (unsigned long)scmd);
	mod_timer(&timer, jiffies + 5 * HZ);
}

/**
 *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
 *	@qc: Storage for translated ATA taskfile
 *
 *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
 *	(to start). Perhaps these commands should be preceded by
 *	CHECK POWER MODE to see what power mode the device is already in.
 *	[See SAT revision 5 at www.t10.org]
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 *
 *	RETURNS:
 *	Zero on success, non-zero on error.
 */
static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
{