[PATCH] libata: implement ata_exec_internal_sg()

Sg'ify ata_exec_internal() and call it ata_exec_internal_sg().
Wrapper function around ata_exec_internal_sg() is implemented to
provide ata_exec_internal() interface.

Signed-off-by: Tejun Heo <htejun@gmail.com>
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 2d532da..ca6f36c 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -58,6 +58,10 @@
 extern unsigned ata_exec_internal(struct ata_device *dev,
 				  struct ata_taskfile *tf, const u8 *cdb,
 				  int dma_dir, void *buf, unsigned int buflen);
+extern unsigned ata_exec_internal_sg(struct ata_device *dev,
+				     struct ata_taskfile *tf, const u8 *cdb,
+				     int dma_dir, struct scatterlist *sg,
+				     unsigned int n_elem);
 extern unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd);
 extern int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
 			   unsigned int flags, u16 *id);