block: Merge .bdrv_co_writev{,_flags} in drivers

We have too many driver callback interfaces; simplify the mess
somewhat by merging the flags parameter of .bdrv_co_writev_flags()
into .bdrv_co_writev().  Note that as long as a driver doesn't set
.supported_write_flags, the flags argument will be 0 and behavior is
identical.  Also note that the public function bdrv_co_writev() still
lacks a flags argument; so the driver signature is thus intentionally
slightly different.  But that's not the end of the world, nor the first
time that the driver interface differs slightly from the public
interface.

Ideally, we should be rewriting all of these drivers to use modern
byte-based interfaces.  But that's a more invasive patch to write
and audit, compared to the simplification done here.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/block/vhdx.c b/block/vhdx.c
index c3a4220a35..0b1e21c750 100644
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -1226,7 +1226,8 @@ int vhdx_user_visible_write(BlockDriverState *bs, BDRVVHDXState *s)
 }
 
 static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num,
-                                      int nb_sectors, QEMUIOVector *qiov)
+                                       int nb_sectors, QEMUIOVector *qiov,
+                                       int flags)
 {
     int ret = -ENOTSUP;
     BDRVVHDXState *s = bs->opaque;
@@ -1242,6 +1243,7 @@ static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num,
     uint64_t bat_prior_offset = 0;
     bool bat_update = false;
 
+    assert(!flags);
     qemu_iovec_init(&hd_qiov, qiov->niov);
 
     qemu_co_mutex_lock(&s->lock);