[PULL 3/4] block/nbd: extract the common cleanup code

[Eric Blake <eblake@redhat.com>]

From: Pan Nengyuan <pannengyuan@huawei.com>

The BDRVNBDState cleanup code is common in two places, add
nbd_clear_bdrvstate() function to do these cleanups.

Suggested-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <1575517528-44312-2-git-send-email-pannengyuan@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: fix compilation error and commit message]
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 block/nbd.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/block/nbd.c b/block/nbd.c
index f69e61e68ad6..ed0f93ab27a9 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -95,6 +95,19 @@ typedef struct BDRVNBDState {

 static int nbd_client_connect(BlockDriverState *bs, Error **errp);

+static void nbd_clear_bdrvstate(BDRVNBDState *s)
+{
+    object_unref(OBJECT(s->tlscreds));
+    qapi_free_SocketAddress(s->saddr);
+    s->saddr = NULL;
+    g_free(s->export);
+    s->export = NULL;
+    g_free(s->tlscredsid);
+    s->tlscredsid = NULL;
+    g_free(s->x_dirty_bitmap);
+    s->x_dirty_bitmap = NULL;
+}
+
 static void nbd_channel_error(BDRVNBDState *s, int ret)
 {
     if (ret == -EIO) {
@@ -1879,11 +1892,7 @@ static int nbd_process_options(BlockDriverState *bs, QDict *options,

  error:
     if (ret < 0) {
-        object_unref(OBJECT(s->tlscreds));
-        qapi_free_SocketAddress(s->saddr);
-        g_free(s->export);
-        g_free(s->tlscredsid);
-        g_free(s->x_dirty_bitmap);
+        nbd_clear_bdrvstate(s);
     }
     qemu_opts_del(opts);
     return ret;
@@ -1962,12 +1971,7 @@ static void nbd_close(BlockDriverState *bs)
     BDRVNBDState *s = bs->opaque;

     nbd_client_close(bs);
-
-    object_unref(OBJECT(s->tlscreds));
-    qapi_free_SocketAddress(s->saddr);
-    g_free(s->export);
-    g_free(s->tlscredsid);
-    g_free(s->x_dirty_bitmap);
+    nbd_clear_bdrvstate(s);
 }

 static int64_t nbd_getlength(BlockDriverState *bs)
-- 
2.24.1