Commit 6ddcd3b0 authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
Browse files

libata: during revalidation, check n_sectors after device is configured 



Device might be resized during ata_dev_configure() due to HPA or
(later) ACPI _GTF.  Currently it's worked around by caching n_sectors
before turning off HPA.  The cached original size is overwritten if
the device is reconfigured without being hardreset - which always
happens after configuring trasnfer mode.  If the device gets hardreset
for some reason after that, revalidation fails with -ENODEV.

This patch makes size checking more robust by moving n_sectors check
from ata_dev_reread_id() to ata_dev_revalidate() after the device is
fully configured.  No matter what happens during configuration, a
device must have the same n_sectors after fully configured to be
treated as the same device.

Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent fe30911b

drivers/ata/libata-core.c

+15 −18
Original line number Diff line number Diff line
@@ -1919,7 +1919,6 @@ int ata_dev_configure(struct ata_device *dev) 
			snprintf(revbuf, 7, "ATA-%d",  ata_id_major_version(id));



		dev->n_sectors = ata_id_n_sectors(id);

		dev->n_sectors_boot = dev->n_sectors;



		/* SCSI only uses 4-char revisions, dump full 8 chars from ATA */

		ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
@@ -3632,7 +3631,6 @@ static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class, 
	const u16 *old_id = dev->id;

	unsigned char model[2][ATA_ID_PROD_LEN + 1];

	unsigned char serial[2][ATA_ID_SERNO_LEN + 1];

	u64 new_n_sectors;



	if (dev->class != new_class) {

		ata_dev_printk(dev, KERN_INFO, "class mismatch %d != %d\n",
@@ -3644,7 +3642,6 @@ static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class, 
	ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));

	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));

	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));

	new_n_sectors = ata_id_n_sectors(new_id);



	if (strcmp(model[0], model[1])) {

		ata_dev_printk(dev, KERN_INFO, "model number mismatch "
@@ -3658,19 +3655,6 @@ static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class, 
		return 0;

	}



	if (dev->class == ATA_DEV_ATA && dev->n_sectors != new_n_sectors) {

		ata_dev_printk(dev, KERN_INFO, "n_sectors mismatch "

			       "%llu != %llu\n",

			       (unsigned long long)dev->n_sectors,

			       (unsigned long long)new_n_sectors);

		/* Are we the boot time size - if so we appear to be the

		   same disk at this point and our HPA got reapplied */

		if (ata_ignore_hpa && dev->n_sectors_boot == new_n_sectors 

		    && ata_id_hpa_enabled(new_id))

			return 1;

		return 0;

	}



	return 1;

}
@@ -3723,6 +3707,7 @@ int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags) 
 */

int ata_dev_revalidate(struct ata_device *dev, unsigned int readid_flags)

{

	u64 n_sectors = dev->n_sectors;

	int rc;



	if (!ata_dev_enabled(dev))
@@ -3735,7 +3720,19 @@ int ata_dev_revalidate(struct ata_device *dev, unsigned int readid_flags) 


	/* configure device according to the new ID */

	rc = ata_dev_configure(dev);

	if (rc == 0)

	if (rc)

		goto fail;



	/* verify n_sectors hasn't changed */

	if (dev->class == ATA_DEV_ATA && dev->n_sectors != n_sectors) {

		ata_dev_printk(dev, KERN_INFO, "n_sectors mismatch "

			       "%llu != %llu\n",

			       (unsigned long long)n_sectors,

			       (unsigned long long)dev->n_sectors);

		rc = -ENODEV;

		goto fail;

	}



	return 0;



 fail:

include/linux/libata.h

+0 −1
Original line number Diff line number Diff line
@@ -431,7 +431,6 @@ struct ata_device { 
	struct scsi_device	*sdev;		/* attached SCSI device */

	/* n_sector is used as CLEAR_OFFSET, read comment above CLEAR_OFFSET */

	u64			n_sectors;	/* size of device, if ATA */

	u64			n_sectors_boot;	/* size of ATA device at startup */

	unsigned int		class;		/* ATA_DEV_xxx */

	u16			id[ATA_ID_WORDS]; /* IDENTIFY xxx DEVICE data */

	u8			pio_mode;

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