bsg: add SG_IO to SG v4

This adds SG_IO support to SG v4.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 21 insertions, 2 deletions

diff --git a/block/bsg.c b/block/bsg.c
index 6d139d20ec99..9dc5d36a52e5 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -945,8 +945,27 @@ bsg_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
                 void __user *uarg = (void __user *) arg;
                 return scsi_cmd_ioctl(file, bd->disk, cmd, uarg);
         }
-        case SG_IO:
-                return -EINVAL;
+        case SG_IO: {
+                struct request *rq;
+                struct bio *bio;
+                struct sg_io_v4 hdr;
+
+                if (copy_from_user(&hdr, uarg, sizeof(hdr)))
+                        return -EFAULT;
+
+                rq = bsg_map_hdr(bd, &hdr);
+                if (IS_ERR(rq))
+                        return PTR_ERR(rq);
+
+                bio = rq->bio;
+                blk_execute_rq(bd->queue, bd->disk, rq, 0);
+                blk_complete_sgv4_hdr_rq(rq, &hdr, bio);
+
+                if (copy_to_user(uarg, &hdr, sizeof(hdr)))
+                        return -EFAULT;
+                else
+                        return 0;
+        }
         /*
          * block device ioctls
          */