block: Add ioctl parameter fields to BlockRequest

The two fields that will be used by ioctl handling code later are added
as union, because it's used exclusively by ioctl code which dosn't need
the four fields in the other struct of the union.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1447064214-29930-6-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 12 insertions, 4 deletions

diff --git a/include/block/block.h b/include/block/block.h
index 610db923d5..c8b40b739f 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -335,10 +335,18 @@ void bdrv_aio_cancel_async(BlockAIOCB *acb);
 
 typedef struct BlockRequest {
     /* Fields to be filled by multiwrite caller */
-    int64_t sector;
-    int nb_sectors;
-    int flags;
-    QEMUIOVector *qiov;
+    union {
+        struct {
+            int64_t sector;
+            int nb_sectors;
+            int flags;
+            QEMUIOVector *qiov;
+        };
+        struct {
+            int req;
+            void *buf;
+        };
+    };
     BlockCompletionFunc *cb;
     void *opaque;