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

Commit b00eec1d authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
Browse files

[PATCH] libata: add per-device max_sectors 



If a low level driver wants to control max_sectors, it had to adjust
ap->host->max_sectors and set ATA_DFLAG_LOCK_SECTORS to tell
ata_scsi_slave_config not to override the limit.  This is not only
cumbersome but also incorrect for hosts which support more than one
devices per port.

This patch adds per-device ->max_sectors.  If the field is unset
(zero), libata core layer will adjust ->max_sectors according to
default rules.  If the field is set, libata honors the setting.

Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
Signed-off-by: default avatarJeff Garzik <jgarzik@pobox.com>
parent 6e7846e9

drivers/scsi/libata-core.c

+1 −3
Original line number Diff line number Diff line
@@ -1147,9 +1147,7 @@ void ata_dev_config(struct ata_port *ap, unsigned int i) 
		printk(KERN_INFO "ata%u(%u): applying bridge limits\n",

		       ap->id, i);

		ap->udma_mask &= ATA_UDMA5;

		ap->host->max_sectors = ATA_MAX_SECTORS;

		ap->host->hostt->max_sectors = ATA_MAX_SECTORS;

		ap->device[i].flags |= ATA_DFLAG_LOCK_SECTORS;

		ap->device[i].max_sectors = ATA_MAX_SECTORS;

	}



	if (ap->ops->dev_config)

drivers/scsi/libata-scsi.c

+9 −9
Original line number Diff line number Diff line
@@ -684,23 +684,23 @@ int ata_scsi_slave_config(struct scsi_device *sdev) 
	if (sdev->id < ATA_MAX_DEVICES) {

		struct ata_port *ap;

		struct ata_device *dev;

		unsigned int max_sectors;



		ap = (struct ata_port *) &sdev->host->hostdata[0];

		dev = &ap->device[sdev->id];



		/* TODO: 1024 is an arbitrary number, not the

		/* TODO: 2048 is an arbitrary number, not the

		 * hardware maximum.  This should be increased to

		 * 65534 when Jens Axboe's patch for dynamically

		 * determining max_sectors is merged.

		 */

		if ((dev->flags & ATA_DFLAG_LBA48) &&

		    ((dev->flags & ATA_DFLAG_LOCK_SECTORS) == 0)) {

			/*

			 * do not overwrite sdev->host->max_sectors, since

			 * other drives on this host may not support LBA48

			 */

			blk_queue_max_sectors(sdev->request_queue, 2048);

		}

		max_sectors = ATA_MAX_SECTORS;

		if (dev->flags & ATA_DFLAG_LBA48)

			max_sectors = 2048;

		if (dev->max_sectors)

			max_sectors = dev->max_sectors;



		blk_queue_max_sectors(sdev->request_queue, max_sectors);



		/*

		 * SATA DMA transfers must be multiples of 4 byte, so

drivers/scsi/sata_sil.c

+1 −3
Original line number Diff line number Diff line
@@ -354,9 +354,7 @@ static void sil_dev_config(struct ata_port *ap, struct ata_device *dev) 
	     (quirks & SIL_QUIRK_MOD15WRITE))) {

		printk(KERN_INFO "ata%u(%u): applying Seagate errata fix (mod15write workaround)\n",

		       ap->id, dev->devno);

		ap->host->max_sectors = 15;

		ap->host->hostt->max_sectors = 15;

		dev->flags |= ATA_DFLAG_LOCK_SECTORS;

		dev->max_sectors = 15;

		return;

	}

include/linux/libata.h

+2 −2
Original line number Diff line number Diff line
@@ -122,8 +122,7 @@ enum { 
	/* struct ata_device stuff */

	ATA_DFLAG_LBA48		= (1 << 0), /* device supports LBA48 */

	ATA_DFLAG_PIO		= (1 << 1), /* device currently in PIO mode */

	ATA_DFLAG_LOCK_SECTORS	= (1 << 2), /* don't adjust max_sectors */

	ATA_DFLAG_LBA		= (1 << 3), /* device supports LBA */

	ATA_DFLAG_LBA		= (1 << 2), /* device supports LBA */



	ATA_DEV_UNKNOWN		= 0,	/* unknown device */

	ATA_DEV_ATA		= 1,	/* ATA device */
@@ -348,6 +347,7 @@ struct ata_device { 


	unsigned int		multi_count;	/* sectors count for

						   READ/WRITE MULTIPLE */

	unsigned int		max_sectors;	/* per-device max sectors */

	unsigned int		cdb_len;



	/* for CHS addressing */