commit 5b3639371c3e220b41cd2eae8c34c49ad38ef527
author Max Reitz <mreitz@redhat.com> Tue May 17 16:41:31 2016 +0200
committer Kevin Wolf <kwolf@redhat.com> Wed May 25 19:04:10 2016 +0200
tree 0f46cc379f81b2ed90b97a36e3fd1b6687e6958a
parent 9bddf759790cf1b9c46889f8f8370c90e6ca7610

block: Make bdrv_open() return a BDS

There are no callers to bdrv_open() or bdrv_open_inherit() left that
pass a pointer to a non-NULL BDS pointer as the first argument of these
functions, so we can finally drop that parameter and just make them
return the new BDS.

Generally, the following pattern is applied:

    bs = NULL;
    ret = bdrv_open(&bs, ..., &local_err);
    if (ret < 0) {
        error_propagate(errp, local_err);
        ...
    }

by

    bs = bdrv_open(..., errp);
    if (!bs) {
        ret = -EINVAL;
        ...
    }

Of course, there are only a few instances where the pattern is really
pure.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/block-backend.c

diff --git a/block/block-backend.c b/block/block-backend.c
index b96323f..bc1f071 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -152,7 +152,6 @@
 {
     BlockBackend *blk;
     BlockDriverState *bs;
-    int ret;
 
     blk = blk_new(errp);
     if (!blk) {
@@ -160,9 +159,8 @@
         return NULL;
     }
 
-    bs = NULL;
-    ret = bdrv_open(&bs, filename, reference, options, flags, errp);
-    if (ret < 0) {
+    bs = bdrv_open(filename, reference, options, flags, errp);
+    if (!bs) {
         blk_unref(blk);
         return NULL;
     }