[PATCH] libata-hp-prep: implement ata_dev_init()

Move initialization of struct ata_device into ata_dev_init() in
preparation for hotplug.  This patch calls ata_dev_init() from
ata_host_init() and thus makes no functional difference.

Signed-off-by: Tejun Heo <htejun@gmail.com>

drivers/scsi/libata-core.c

@@ -5141,6 +5141,26 @@ static void ata_host_remove(struct ata_port *ap, unsigned int do_unregister)
 	ap->ops->port_stop(ap);
 }
 
+/**
+ *	ata_dev_init - Initialize an ata_device structure
+ *	@dev: Device structure to initialize
+ *
+ *	Initialize @dev in preparation for probing.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+void ata_dev_init(struct ata_device *dev)
+{
+	struct ata_port *ap = dev->ap;
+
+	memset((void *)dev, 0, sizeof(*dev));
+	dev->devno = dev - ap->device;
+	dev->pio_mask = UINT_MAX;
+	dev->mwdma_mask = UINT_MAX;
+	dev->udma_mask = UINT_MAX;
+}
+
 /**
  *	ata_host_init - Initialize an ata_port structure
  *	@ap: Structure to initialize
@@ -5155,7 +5175,6 @@ static void ata_host_remove(struct ata_port *ap, unsigned int do_unregister)
  *	LOCKING:
  *	Inherited from caller.
  */
-
 static void ata_host_init(struct ata_port *ap, struct Scsi_Host *host,
 			  struct ata_host_set *host_set,
 			  const struct ata_probe_ent *ent, unsigned int port_no)
@@ -5199,10 +5218,7 @@ static void ata_host_init(struct ata_port *ap, struct Scsi_Host *host,
 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
 		struct ata_device *dev = &ap->device[i];
 		dev->ap = ap;
-		dev->devno = i;
-		dev->pio_mask = UINT_MAX;
-		dev->mwdma_mask = UINT_MAX;
-		dev->udma_mask = UINT_MAX;
+		ata_dev_init(dev);
 	}
 
 #ifdef ATA_IRQ_TRAP

drivers/scsi/libata.h

@@ -62,6 +62,7 @@ extern int ata_check_atapi_dma(struct ata_queued_cmd *qc);
 extern void ata_dev_select(struct ata_port *ap, unsigned int device,
                            unsigned int wait, unsigned int can_sleep);
 extern void swap_buf_le16(u16 *buf, unsigned int buf_words);
+extern void ata_dev_init(struct ata_device *dev);
 extern int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg);
 extern int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg);