[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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 1a373b4..61cba39 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1147,9 +1147,7 @@
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)
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 3628fed..86da465 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -684,23 +684,23 @@
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
diff --git a/drivers/scsi/sata_sil.c b/drivers/scsi/sata_sil.c
index 61c4ac7..6c482c8 100644
--- a/drivers/scsi/sata_sil.c
+++ b/drivers/scsi/sata_sil.c
@@ -354,9 +354,7 @@
(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;
}
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 853c988..afe4645 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -122,8 +122,7 @@
/* 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 @@
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 */