[SCSI] unify SCSI_IOCTL_SEND_COMMAND implementations

We currently have two implementations of this obsolete ioctl, one in
the block layer and one in the scsi code.  Both of them have drawbacks.

This patch kills the scsi layer version after updating the block version
with the missing bits:

 - argument checking
 - use scatterlist I/O
 - set number of retries based on the submitted command

This is the last user of non-S/G I/O except for the gdth driver, so
getting this in ASAP and through the scsi tree would be nie to kill
the non-S/G I/O path.  Jens, what do you think about adding a check
for non-S/G I/O in the midlayer?

Thanks to  Or Gerlitz for testing this patch.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index d0cac8b58de7..59e1259b1c40 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -17,6 +17,8 @@
 
 #include <asm/scatterlist.h>
 
+struct scsi_ioctl_command;
+
 struct request_queue;
 typedef struct request_queue request_queue_t;
 struct elevator_queue;
@@ -611,6 +613,8 @@ extern void blk_plug_device(request_queue_t *);
 extern int blk_remove_plug(request_queue_t *);
 extern void blk_recount_segments(request_queue_t *, struct bio *);
 extern int scsi_cmd_ioctl(struct file *, struct gendisk *, unsigned int, void __user *);
+extern int sg_scsi_ioctl(struct file *, struct request_queue *,
+		struct gendisk *, struct scsi_ioctl_command __user *);
 extern void blk_start_queue(request_queue_t *q);
 extern void blk_stop_queue(request_queue_t *q);
 extern void blk_sync_queue(struct request_queue *q);