nbd: Improve debug traces on little-endian

Print debug tracing messages while data is still in native
ordering, rather than after we've potentially swapped it into
network order for transmission.  Also, it's nice if the server
mentions what it is replying, to correlate it to with what the
client says it is receiving.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1459913704-19949-4-git-send-email-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/nbd/client.c b/nbd/client.c
index d9b7a9b07edba1055446527d79df2ecc584cd412..1593cd6c0e0f0517258b2f533f6f6dce95adb13e 100644 (file)
--- a/nbd/client.c
+++ b/nbd/client.c
@@ -628,16 +628,16 @@ ssize_t nbd_send_request(QIOChannel *ioc, struct nbd_request *request)
     uint8_t buf[NBD_REQUEST_SIZE];
     ssize_t ret;
 
+    TRACE("Sending request to server: "
+          "{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}",
+          request->from, request->len, request->handle, request->type);
+
     cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC);
     cpu_to_be32w((uint32_t*)(buf + 4), request->type);
     cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
     cpu_to_be64w((uint64_t*)(buf + 16), request->from);
     cpu_to_be32w((uint32_t*)(buf + 24), request->len);
 
-    TRACE("Sending request to server: "
-          "{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}",
-          request->from, request->len, request->handle, request->type);
-
     ret = write_sync(ioc, buf, sizeof(buf));
     if (ret < 0) {
         return ret;

diff --git a/nbd/server.c b/nbd/server.c
index 98e39576053c22fe9d47af4c08ccf600251bc357..6d9c15a0b04ad1a9401088bf7aa2837c803f303f 100644 (file)
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -656,6 +656,9 @@ static ssize_t nbd_send_reply(QIOChannel *ioc, struct nbd_reply *reply)
 
     reply->error = system_errno_to_nbd_errno(reply->error);
 
+    TRACE("Sending response to client: { .error = %d, handle = %" PRIu64 " }",
+          reply->error, reply->handle);
+
     /* Reply
        [ 0 ..  3]    magic   (NBD_REPLY_MAGIC)
        [ 4 ..  7]    error   (0 == no error)
@@ -665,8 +668,6 @@ static ssize_t nbd_send_reply(QIOChannel *ioc, struct nbd_reply *reply)
     stl_be_p(buf + 4, reply->error);
     stq_be_p(buf + 8, reply->handle);
 
-    TRACE("Sending response to client");
-
     ret = write_sync(ioc, buf, sizeof(buf));
     if (ret < 0) {
         return ret;