RESEND: libata: check cdb len per dev instead of per host

Resending, with s/printk/DPRINTK/ as pointed out by Alan.

Fix libata to perform CDB len validation per device
rather than per host.  This way, validation still works
when we have a mix of 12-byte and 16-byte devices on
a common host interface.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/ata/libata-core.c

@@ -1560,20 +1560,6 @@ static void ata_dev_config_ncq(struct ata_device *dev,
 		snprintf(desc, desc_sz, "NCQ (depth %d/%d)", hdepth, ddepth);
 }
 
-static void ata_set_port_max_cmd_len(struct ata_port *ap)
-{
-	int i;
-
-	if (ap->scsi_host) {
-		unsigned int len = 0;
-
-		for (i = 0; i < ATA_MAX_DEVICES; i++)
-			len = max(len, ap->device[i].cdb_len);
-
-		ap->scsi_host->max_cmd_len = len;
-	}
-}
-
 /**
  *	ata_dev_configure - Configure the specified ATA/ATAPI device
  *	@dev: Target device to configure
@@ -1773,8 +1759,6 @@ int ata_dev_configure(struct ata_device *dev)
 		}
 	}
 
-	ata_set_port_max_cmd_len(ap);
-
 	/* limit bridge transfers to udma5, 200 sectors */
 	if (ata_dev_knobble(dev)) {
 		if (ata_msg_drv(ap) && print_info)
@@ -5670,7 +5654,7 @@ static void ata_port_init_shost(struct ata_port *ap, struct Scsi_Host *shost)
 	shost->max_id = 16;
 	shost->max_lun = 1;
 	shost->max_channel = 1;
-	shost->max_cmd_len = 12;
+	shost->max_cmd_len = 16;
 }
 
 /**

drivers/ata/libata-scsi.c

@@ -2792,8 +2792,9 @@ static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
 {
 	int rc = 0;
 
-	if (unlikely(!scmd->cmd_len)) {
-		ata_dev_printk(dev, KERN_WARNING, "WARNING: zero len CDB\n");
+	if (unlikely(!scmd->cmd_len || scmd->cmd_len > dev->cdb_len)) {
+		DPRINTK("bad CDB len=%u, max=%u\n",
+			scmd->cmd_len, dev->cdb_len);
 		scmd->result = DID_ERROR << 16;
 		done(scmd);
 		return 0;