nbd/server: drop old-style negotiation

After the previous commit, nbd_client_new's first parameter is always
NULL. Let's drop it with all corresponding old-style negotiation code
path which is unreachable now.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20181003170228.95973-3-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: re-wrap short line]
Signed-off-by: Eric Blake <eblake@redhat.com>

blockdev-nbd.c

@@ -36,8 +36,7 @@ static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
                        gpointer opaque)
 {
     qio_channel_set_name(QIO_CHANNEL(cioc), "nbd-server");
-    nbd_client_new(NULL, cioc,
-                   nbd_server->tlscreds, NULL,
+    nbd_client_new(cioc, nbd_server->tlscreds, NULL,
                    nbd_blockdev_client_closed);
 }
 

include/block/nbd.h

@@ -308,8 +308,7 @@ void nbd_export_set_name(NBDExport *exp, const char *name);
 void nbd_export_set_description(NBDExport *exp, const char *description);
 void nbd_export_close_all(void);
 
-void nbd_client_new(NBDExport *exp,
-                    QIOChannelSocket *sioc,
+void nbd_client_new(QIOChannelSocket *sioc,
                     QCryptoTLSCreds *tlscreds,
                     const char *tlsaclname,
                     void (*close_fn)(NBDClient *, bool));

nbd/server.c

@@ -1253,7 +1253,6 @@ static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
     const uint16_t myflags = (NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_TRIM |
                               NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA |
                               NBD_FLAG_SEND_WRITE_ZEROES | NBD_FLAG_SEND_CACHE);
-    bool oldStyle;
 
     /* Old style negotiation header, no room for options
         [ 0 ..   7]   passwd       ("NBDMAGIC")
@@ -1274,33 +1273,19 @@ static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
     trace_nbd_negotiate_begin();
     memcpy(buf, "NBDMAGIC", 8);
 
-    oldStyle = client->exp != NULL && !client->tlscreds;
-    if (oldStyle) {
-        trace_nbd_negotiate_old_style(client->exp->size,
-                                      client->exp->nbdflags | myflags);
-        stq_be_p(buf + 8, NBD_CLIENT_MAGIC);
-        stq_be_p(buf + 16, client->exp->size);
-        stl_be_p(buf + 24, client->exp->nbdflags | myflags);
+    stq_be_p(buf + 8, NBD_OPTS_MAGIC);
+    stw_be_p(buf + 16, NBD_FLAG_FIXED_NEWSTYLE | NBD_FLAG_NO_ZEROES);
 
-        if (nbd_write(client->ioc, buf, sizeof(buf), errp) < 0) {
-            error_prepend(errp, "write failed: ");
-            return -EINVAL;
-        }
-    } else {
-        stq_be_p(buf + 8, NBD_OPTS_MAGIC);
-        stw_be_p(buf + 16, NBD_FLAG_FIXED_NEWSTYLE | NBD_FLAG_NO_ZEROES);
-
-        if (nbd_write(client->ioc, buf, 18, errp) < 0) {
-            error_prepend(errp, "write failed: ");
-            return -EINVAL;
-        }
-        ret = nbd_negotiate_options(client, myflags, errp);
-        if (ret != 0) {
-            if (ret < 0) {
-                error_prepend(errp, "option negotiation failed: ");
-            }
-            return ret;
+    if (nbd_write(client->ioc, buf, 18, errp) < 0) {
+        error_prepend(errp, "write failed: ");
+        return -EINVAL;
+    }
+    ret = nbd_negotiate_options(client, myflags, errp);
+    if (ret != 0) {
+        if (ret < 0) {
+            error_prepend(errp, "option negotiation failed: ");
         }
+        return ret;
     }
 
     assert(!client->optlen);
@@ -2396,13 +2381,8 @@ static void nbd_client_receive_next_request(NBDClient *client)
 static coroutine_fn void nbd_co_client_start(void *opaque)
 {
     NBDClient *client = opaque;
-    NBDExport *exp = client->exp;
     Error *local_err = NULL;
 
-    if (exp) {
-        nbd_export_get(exp);
-        QTAILQ_INSERT_TAIL(&exp->clients, client, next);
-    }
     qemu_co_mutex_init(&client->send_lock);
 
     if (nbd_negotiate(client, &local_err)) {
@@ -2417,13 +2397,11 @@ static coroutine_fn void nbd_co_client_start(void *opaque)
 }
 
 /*
- * Create a new client listener on the given export @exp, using the
- * given channel @sioc.  Begin servicing it in a coroutine.  When the
- * connection closes, call @close_fn with an indication of whether the
- * client completed negotiation.
+ * Create a new client listener using the given channel @sioc.
+ * Begin servicing it in a coroutine.  When the connection closes, call
+ * @close_fn with an indication of whether the client completed negotiation.
  */
-void nbd_client_new(NBDExport *exp,
-                    QIOChannelSocket *sioc,
+void nbd_client_new(QIOChannelSocket *sioc,
                     QCryptoTLSCreds *tlscreds,
                     const char *tlsaclname,
                     void (*close_fn)(NBDClient *, bool))
@@ -2433,7 +2411,6 @@ void nbd_client_new(NBDExport *exp,
 
     client = g_new0(NBDClient, 1);
     client->refcount = 1;
-    client->exp = exp;
     client->tlscreds = tlscreds;
     if (tlscreds) {
         object_ref(OBJECT(client->tlscreds));

qemu-nbd.c

@@ -354,7 +354,7 @@ static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
 
     nb_fds++;
     nbd_update_server_watch();
-    nbd_client_new(NULL, cioc, tlscreds, NULL, nbd_client_closed);
+    nbd_client_new(cioc, tlscreds, NULL, nbd_client_closed);
 }
 
 static void nbd_update_server_watch(void)