[PULL 33/34] block/nbd: add nbd_client_connected() helper

[Eric Blake <eblake@redhat.com>]

From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

We already have two similar helpers for other state. Let's add another
one for convenience.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210610100802.5888-32-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 block/nbd.c | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/block/nbd.c b/block/nbd.c
index 5e7e238b4790..5cfb749e089d 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -122,15 +122,20 @@ static void nbd_clear_bdrvstate(BlockDriverState *bs)
     s->x_dirty_bitmap = NULL;
 }

+static bool nbd_client_connected(BDRVNBDState *s)
+{
+    return qatomic_load_acquire(&s->state) == NBD_CLIENT_CONNECTED;
+}
+
 static void nbd_channel_error(BDRVNBDState *s, int ret)
 {
     if (ret == -EIO) {
-        if (qatomic_load_acquire(&s->state) == NBD_CLIENT_CONNECTED) {
+        if (nbd_client_connected(s)) {
             s->state = s->reconnect_delay ? NBD_CLIENT_CONNECTING_WAIT :
                                             NBD_CLIENT_CONNECTING_NOWAIT;
         }
     } else {
-        if (qatomic_load_acquire(&s->state) == NBD_CLIENT_CONNECTED) {
+        if (nbd_client_connected(s)) {
             qio_channel_shutdown(s->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
         }
         s->state = NBD_CLIENT_QUIT;
@@ -228,7 +233,7 @@ static void nbd_client_attach_aio_context(BlockDriverState *bs,
      * s->connection_co is either yielded from nbd_receive_reply or from
      * nbd_co_reconnect_loop()
      */
-    if (qatomic_load_acquire(&s->state) == NBD_CLIENT_CONNECTED) {
+    if (nbd_client_connected(s)) {
         qio_channel_attach_aio_context(QIO_CHANNEL(s->ioc), new_context);
     }

@@ -499,7 +504,7 @@ static coroutine_fn void nbd_connection_entry(void *opaque)
             nbd_co_reconnect_loop(s);
         }

-        if (qatomic_load_acquire(&s->state) != NBD_CLIENT_CONNECTED) {
+        if (!nbd_client_connected(s)) {
             continue;
         }

@@ -578,7 +583,7 @@ static int nbd_co_send_request(BlockDriverState *bs,
         qemu_co_queue_wait(&s->free_sema, &s->send_mutex);
     }

-    if (qatomic_load_acquire(&s->state) != NBD_CLIENT_CONNECTED) {
+    if (!nbd_client_connected(s)) {
         rc = -EIO;
         goto err;
     }
@@ -605,8 +610,7 @@ static int nbd_co_send_request(BlockDriverState *bs,
     if (qiov) {
         qio_channel_set_cork(s->ioc, true);
         rc = nbd_send_request(s->ioc, request);
-        if (qatomic_load_acquire(&s->state) == NBD_CLIENT_CONNECTED &&
-            rc >= 0) {
+        if (nbd_client_connected(s) && rc >= 0) {
             if (qio_channel_writev_all(s->ioc, qiov->iov, qiov->niov,
                                        NULL) < 0) {
                 rc = -EIO;
@@ -931,7 +935,7 @@ static coroutine_fn int nbd_co_do_receive_one_chunk(
     s->requests[i].receiving = true;
     qemu_coroutine_yield();
     s->requests[i].receiving = false;
-    if (qatomic_load_acquire(&s->state) != NBD_CLIENT_CONNECTED) {
+    if (!nbd_client_connected(s)) {
         error_setg(errp, "Connection closed");
         return -EIO;
     }
@@ -1090,7 +1094,7 @@ static bool nbd_reply_chunk_iter_receive(BDRVNBDState *s,
     NBDReply local_reply;
     NBDStructuredReplyChunk *chunk;
     Error *local_err = NULL;
-    if (qatomic_load_acquire(&s->state) != NBD_CLIENT_CONNECTED) {
+    if (!nbd_client_connected(s)) {
         error_setg(&local_err, "Connection closed");
         nbd_iter_channel_error(iter, -EIO, &local_err);
         goto break_loop;
@@ -1115,8 +1119,7 @@ static bool nbd_reply_chunk_iter_receive(BDRVNBDState *s,
     }

     /* Do not execute the body of NBD_FOREACH_REPLY_CHUNK for simple reply. */
-    if (nbd_reply_is_simple(reply) ||
-        qatomic_load_acquire(&s->state) != NBD_CLIENT_CONNECTED) {
+    if (nbd_reply_is_simple(reply) || !nbd_client_connected(s)) {
         goto break_loop;
     }

-- 
2.31.1