[PATCH 11/24] scsi-multipath: add scsi_mpath_ioctl()

[John Garry]

Add a callback for the scsi_mpath_ioctl.bdev_ioctl .

Since this is concerned with the mpath_disk, we rely on the scsi_driver
to handle the ioctl.

Signed-off-by: John Garry <john.g.garry@xxxxxxxxxx>
---
 drivers/scsi/scsi_multipath.c | 21 +++++++++++++++++++++
 include/scsi/scsi_driver.h    |  2 ++
 2 files changed, 23 insertions(+)

diff --git a/drivers/scsi/scsi_multipath.c b/drivers/scsi/scsi_multipath.c
index 16b1f84fc552c..36f13605b44e7 100644
--- a/drivers/scsi/scsi_multipath.c
+++ b/drivers/scsi/scsi_multipath.c
@@ -320,7 +320,28 @@ static enum mpath_iopolicy_e scsi_mpath_get_iopolicy(struct mpath_head *mpath_he
 	return mpath_read_iopolicy(&scsi_mpath_head->iopolicy);
 }
 
+static int scsi_mpath_ioctl(struct block_device *bdev,
+			struct mpath_device *mpath_device,
+			blk_mode_t mode, unsigned int cmd,
+			unsigned long arg, int srcu_idx)
+{
+	struct gendisk *disk = bdev->bd_disk;
+	struct mpath_disk *mpath_disk = mpath_gendisk_to_disk(disk);
+	struct mpath_head *mpath_head = mpath_disk->mpath_head;
+	struct scsi_mpath_device *scsi_mpath_dev =
+				to_scsi_mpath_device(mpath_device);
+	struct scsi_device *sdev = scsi_mpath_dev->sdev;
+	struct scsi_driver *drv = to_scsi_driver(sdev->sdev_gendev.driver);
+	int err;
+
+	err = drv->mpath_ioctl(sdev, mode & BLK_OPEN_WRITE, cmd, arg);
+
+	mpath_head_read_unlock(mpath_head, srcu_idx);
+	return err;
+}
+
 struct mpath_head_template smpdt_pr = {
+	.bdev_ioctl = scsi_mpath_ioctl,
 	.get_iopolicy = scsi_mpath_get_iopolicy,
 	.clone_bio = scsi_mpath_clone_bio,
 };
diff --git a/include/scsi/scsi_driver.h b/include/scsi/scsi_driver.h
index 44e50229a75e7..799071b8bdee2 100644
--- a/include/scsi/scsi_driver.h
+++ b/include/scsi/scsi_driver.h
@@ -22,6 +22,8 @@ struct scsi_driver {
 	#ifdef CONFIG_SCSI_MULTIPATH
 	void (*mpath_start_cmd)(struct scsi_cmnd *);
 	void (*mpath_end_cmd)(struct scsi_cmnd *);
+	int (*mpath_ioctl)(struct scsi_device *sdev, blk_mode_t mode,
+					unsigned int cmd, unsigned long arg);
 	struct mpath_disk *(*to_mpath_disk)(struct request *);
 	#endif
 };
-- 
2.43.5