[libata] get-identity ioctl: Fix use of invalid memory pointer

for SAS drivers.

Caught by Ke Wei (and team?) at Marvell.

Also, move the ata_scsi_ioctl export to libata-scsi.c, as that seems to be the
general trend.
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/libata-core.c

@@ -6638,7 +6638,6 @@ EXPORT_SYMBOL_GPL(ata_dev_pair);
 EXPORT_SYMBOL_GPL(ata_port_disable);
 EXPORT_SYMBOL_GPL(ata_ratelimit);
 EXPORT_SYMBOL_GPL(ata_wait_register);
-EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
 EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);

drivers/ata/libata-scsi.c

@@ -423,9 +423,9 @@ int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
  *	RETURNS:
  *	Zero on success, negative errno on error.
  */
-static int ata_get_identity(struct scsi_device *sdev, void __user *arg)
+static int ata_get_identity(struct ata_port *ap, struct scsi_device *sdev,
+			    void __user *arg)
 {
-	struct ata_port *ap = ata_shost_to_port(sdev->host);
 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
 	u16 __user *dst = arg;
 	char buf[40];
@@ -645,7 +645,8 @@ int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
 	return rc;
 }
 
-int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
+int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *scsidev,
+		     int cmd, void __user *arg)
 {
 	int val = -EINVAL, rc = -EINVAL;
 
@@ -663,7 +664,7 @@ int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
 		return 0;
 
 	case HDIO_GET_IDENTITY:
-		return ata_get_identity(scsidev, arg);
+		return ata_get_identity(ap, scsidev, arg);
 
 	case HDIO_DRIVE_CMD:
 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
@@ -682,6 +683,14 @@ int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
 
 	return rc;
 }
+EXPORT_SYMBOL_GPL(ata_sas_scsi_ioctl);
+
+int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
+{
+	return ata_sas_scsi_ioctl(ata_shost_to_port(scsidev->host),
+				scsidev, cmd, arg);
+}
+EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
 
 /**
  *	ata_scsi_qc_new - acquire new ata_queued_cmd reference

drivers/scsi/ipr.c

@@ -4912,7 +4912,7 @@ static int ipr_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
 	if (res && ipr_is_gata(res)) {
 		if (cmd == HDIO_GET_IDENTITY)
 			return -ENOTTY;
-		return ata_scsi_ioctl(sdev, cmd, arg);
+		return ata_sas_scsi_ioctl(res->sata_port->ap, sdev, cmd, arg);
 	}
 
 	return -EINVAL;

drivers/scsi/libsas/sas_scsi_host.c

@@ -717,7 +717,7 @@ int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
 	struct domain_device *dev = sdev_to_domain_dev(sdev);
 
 	if (dev_is_sata(dev))
-		return ata_scsi_ioctl(sdev, cmd, arg);
+		return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
 
 	return -EINVAL;
 }

include/linux/libata.h

@@ -927,6 +927,8 @@ extern void ata_host_init(struct ata_host *, struct device *,
 extern int ata_scsi_detect(struct scsi_host_template *sht);
 extern int ata_scsi_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
 extern int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *));
+extern int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *dev,
+			    int cmd, void __user *arg);
 extern void ata_sas_port_destroy(struct ata_port *);
 extern struct ata_port *ata_sas_port_alloc(struct ata_host *,
 					   struct ata_port_info *, struct Scsi_Host *);