Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 49016aca authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
Browse files

[PATCH] libata: separate out ata_dev_read_id() 



Separate out ata_dev_read_id() from ata_dev_identify().  This is the
first half of splitting ata_dev_identify().  ata_dev_read_id() will
also be used for revalidation.  This patch does not make any behavior
change.

ata_dev_read_id() doesn't modify any of libata-internal data
structures.  It simply reads IDENTIFY page and returns error code on
failure.  INIT_DEV_PARAMS and EDD wrong class code are also handled by
this function.

Re-reading IDENTIFY after INIT_DEV_PARAMS is performed by jumping to
retry: instead of calling ata_dev_reread_id().  This is done because
1. there's retry label anyway 2. ata_dev_reread_id() cannot be used
anywhere else so there's no reason to keep it.

This function is probably the place to set transfer mode to PIO0
before IDENTIFY.  However, reset -> identify -> init_dev_params order
should be kept for pre-ATA4 devices so we cannot set transfer mode
before IDENTIFY for them.  How do we know if a device is post-ATA4
before IDENTIFY?

Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
Signed-off-by: default avatarJeff Garzik <jgarzik@pobox.com>
parent f131883e

drivers/scsi/libata-core.c

+128 −82
Original line number Diff line number Diff line
@@ -903,42 +903,36 @@ unsigned int ata_pio_need_iordy(const struct ata_device *adev) 
}



/**

 *	ata_dev_identify - obtain IDENTIFY x DEVICE page

 *	@ap: port on which device we wish to probe resides

 *	@device: device bus address, starting at zero

 *

 *	Following bus reset, we issue the IDENTIFY [PACKET] DEVICE

 *	command, and read back the 512-byte device information page.

 *	The device information page is fed to us via the standard

 *	PIO-IN protocol, but we hand-code it here. (TODO: investigate

 *	using standard PIO-IN paths)

 *

 *	After reading the device information page, we use several

 *	bits of information from it to initialize data structures

 *	that will be used during the lifetime of the ata_device.

 *	Other data from the info page is used to disqualify certain

 *	older ATA devices we do not wish to support.

 *	ata_dev_read_id - Read ID data from the specified device

 *	@ap: port on which target device resides

 *	@dev: target device

 *	@p_class: pointer to class of the target device (may be changed)

 *	@post_reset: is this read ID post-reset?

 *	@id: buffer to fill IDENTIFY page into

 *

 *	Read ID data from the specified device.  ATA_CMD_ID_ATA is

 *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI

 *	devices.  This function also takes care of EDD signature

 *	misreporting (to be removed once EDD support is gone) and

 *	issues ATA_CMD_INIT_DEV_PARAMS for pre-ATA4 drives.

 *

 *	LOCKING:

 *	Inherited from caller.  Some functions called by this function

 *	obtain the host_set lock.

 *	Kernel thread context (may sleep)

 *

 *	RETURNS:

 *	0 on success, -errno otherwise.

 */



static void ata_dev_identify(struct ata_port *ap, unsigned int device)

static int ata_dev_read_id(struct ata_port *ap, struct ata_device *dev,

			   unsigned int *p_class, int post_reset, u16 *id)

{

	struct ata_device *dev = &ap->device[device];

	unsigned int major_version;

	unsigned long xfer_modes;

	unsigned int class = *p_class;

	unsigned int using_edd;

	struct ata_taskfile tf;

	unsigned int err_mask;

	int i, rc;

	unsigned int err_mask = 0;

	const char *reason;

	int rc;



	if (!ata_dev_present(dev)) {

		DPRINTK("ENTER/EXIT (host %u, dev %u) -- nodev\n",

			ap->id, device);

		return;

	}

	DPRINTK("ENTER, host %u, dev %u\n", ap->id, dev->devno);



	if (ap->ops->probe_reset ||

	    ap->flags & (ATA_FLAG_SRST | ATA_FLAG_SATA_RESET))
@@ -946,30 +940,33 @@ static void ata_dev_identify(struct ata_port *ap, unsigned int device) 
	else

		using_edd = 1;



	DPRINTK("ENTER, host %u, dev %u\n", ap->id, device);



	WARN_ON(dev->class != ATA_DEV_ATA && dev->class != ATA_DEV_ATAPI &&

		dev->class != ATA_DEV_NONE);



	ata_dev_select(ap, device, 1, 1); /* select device 0/1 */

	ata_dev_select(ap, dev->devno, 1, 1); /* select device 0/1 */



 retry:

	ata_tf_init(ap, &tf, device);

	ata_tf_init(ap, &tf, dev->devno);



	if (dev->class == ATA_DEV_ATA) {

	switch (class) {

	case ATA_DEV_ATA:

		tf.command = ATA_CMD_ID_ATA;

		DPRINTK("do ATA identify\n");

	} else {

		break;

	case ATA_DEV_ATAPI:

		tf.command = ATA_CMD_ID_ATAPI;

		DPRINTK("do ATAPI identify\n");

		break;

	default:

		rc = -ENODEV;

		reason = "unsupported class";

		goto err_out;

	}



	tf.protocol = ATA_PROT_PIO;



	err_mask = ata_exec_internal(ap, dev, &tf, DMA_FROM_DEVICE,

				     dev->id, sizeof(dev->id));

				     id, sizeof(id[0]) * ATA_ID_WORDS);



	if (err_mask) {

		rc = -EIO;

		reason = "I/O error";



		if (err_mask & ~AC_ERR_DEV)

			goto err_out;
@@ -984,25 +981,105 @@ static void ata_dev_identify(struct ata_port *ap, unsigned int device) 
		 * ATA software reset (SRST, the default) does not appear

		 * to have this problem.

		 */

		if ((using_edd) && (dev->class == ATA_DEV_ATA)) {

		if ((using_edd) && (class == ATA_DEV_ATA)) {

			u8 err = tf.feature;

			if (err & ATA_ABORTED) {

				dev->class = ATA_DEV_ATAPI;

				class = ATA_DEV_ATAPI;

				goto retry;

			}

		}

		goto err_out;

	}



	swap_buf_le16(dev->id, ATA_ID_WORDS);

	swap_buf_le16(id, ATA_ID_WORDS);



	/* print device capabilities */

	printk(KERN_DEBUG "ata%u: dev %u cfg "

	       "49:%04x 82:%04x 83:%04x 84:%04x 85:%04x 86:%04x 87:%04x 88:%04x\n",

	       ap->id, device, dev->id[49],

	       dev->id[82], dev->id[83], dev->id[84],

	       dev->id[85], dev->id[86], dev->id[87],

	       dev->id[88]);

	       ap->id, dev->devno,

	       id[49], id[82], id[83], id[84], id[85], id[86], id[87], id[88]);



	/* sanity check */

	if ((class == ATA_DEV_ATA) != ata_id_is_ata(id)) {

		rc = -EINVAL;

		reason = "device reports illegal type";

		goto err_out;

	}



	if (post_reset && class == ATA_DEV_ATA) {

		/*

		 * The exact sequence expected by certain pre-ATA4 drives is:

		 * SRST RESET

		 * IDENTIFY

		 * INITIALIZE DEVICE PARAMETERS

		 * anything else..

		 * Some drives were very specific about that exact sequence.

		 */

		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {

			err_mask = ata_dev_init_params(ap, dev);

			if (err_mask) {

				rc = -EIO;

				reason = "INIT_DEV_PARAMS failed";

				goto err_out;

			}



			/* current CHS translation info (id[53-58]) might be

			 * changed. reread the identify device info.

			 */

			post_reset = 0;

			goto retry;

		}

	}



	*p_class = class;

	return 0;



 err_out:

	printk(KERN_WARNING "ata%u: dev %u failed to IDENTIFY (%s)\n",

	       ap->id, dev->devno, reason);

	kfree(id);

	return rc;

}



/**

 *	ata_dev_identify - obtain IDENTIFY x DEVICE page

 *	@ap: port on which device we wish to probe resides

 *	@device: device bus address, starting at zero

 *

 *	Following bus reset, we issue the IDENTIFY [PACKET] DEVICE

 *	command, and read back the 512-byte device information page.

 *	The device information page is fed to us via the standard

 *	PIO-IN protocol, but we hand-code it here. (TODO: investigate

 *	using standard PIO-IN paths)

 *

 *	After reading the device information page, we use several

 *	bits of information from it to initialize data structures

 *	that will be used during the lifetime of the ata_device.

 *	Other data from the info page is used to disqualify certain

 *	older ATA devices we do not wish to support.

 *

 *	LOCKING:

 *	Inherited from caller.  Some functions called by this function

 *	obtain the host_set lock.

 */



static void ata_dev_identify(struct ata_port *ap, unsigned int device)

{

	struct ata_device *dev = &ap->device[device];

	unsigned long xfer_modes;

	int i, rc;



	if (!ata_dev_present(dev)) {

		DPRINTK("ENTER/EXIT (host %u, dev %u) -- nodev\n",

			ap->id, device);

		return;

	}



	DPRINTK("ENTER, host %u, dev %u\n", ap->id, device);



	rc = ata_dev_read_id(ap, dev, &dev->class, 1, dev->id);

	if (rc)

		goto err_out;



	/*

	 * common ATA, ATAPI feature tests
@@ -1027,34 +1104,6 @@ static void ata_dev_identify(struct ata_port *ap, unsigned int device) 
	if (dev->class == ATA_DEV_ATA) {

		dev->n_sectors = ata_id_n_sectors(dev->id);



		if (!ata_id_is_ata(dev->id))	/* sanity check */

			goto err_out_nosup;



		/* get major version */

		major_version = ata_id_major_version(dev->id);



		/*

		 * The exact sequence expected by certain pre-ATA4 drives is:

		 * SRST RESET

		 * IDENTIFY

		 * INITIALIZE DEVICE PARAMETERS

		 * anything else..

		 * Some drives were very specific about that exact sequence.

		 */

		if (major_version < 4 || (!ata_id_has_lba(dev->id))) {

			err_mask = ata_dev_init_params(ap, dev);

			if (err_mask) {

				printk(KERN_ERR "ata%u: failed to init "

				       "parameters, disabled\n", ap->id);

				goto err_out;

			}



			/* current CHS translation info (id[53-58]) might be

			 * changed. reread the identify device info.

			 */

			ata_dev_reread_id(ap, dev);

		}



		if (ata_id_has_lba(dev->id)) {

			dev->flags |= ATA_DFLAG_LBA;
@@ -1064,7 +1113,7 @@ static void ata_dev_identify(struct ata_port *ap, unsigned int device) 
			/* print device info to dmesg */

			printk(KERN_INFO "ata%u: dev %u ATA-%d, max %s, %Lu sectors:%s\n",

			       ap->id, device,

			       major_version,

			       ata_id_major_version(dev->id),

			       ata_mode_string(xfer_modes),

			       (unsigned long long)dev->n_sectors,

			       dev->flags & ATA_DFLAG_LBA48 ? " LBA48" : " LBA");
@@ -1086,7 +1135,7 @@ static void ata_dev_identify(struct ata_port *ap, unsigned int device) 
			/* print device info to dmesg */

			printk(KERN_INFO "ata%u: dev %u ATA-%d, max %s, %Lu sectors: CHS %d/%d/%d\n",

			       ap->id, device,

			       major_version,

			       ata_id_major_version(dev->id),

			       ata_mode_string(xfer_modes),

			       (unsigned long long)dev->n_sectors,

			       (int)dev->cylinders, (int)dev->heads, (int)dev->sectors);
@@ -1098,9 +1147,6 @@ static void ata_dev_identify(struct ata_port *ap, unsigned int device) 


	/* ATAPI-specific feature tests */

	else if (dev->class == ATA_DEV_ATAPI) {

		if (ata_id_is_ata(dev->id))		/* sanity check */

			goto err_out_nosup;



		rc = atapi_cdb_len(dev->id);

		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {

			printk(KERN_WARNING "ata%u: unsupported CDB len\n", ap->id);