Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2018-01-10' into staging

nbd patches for 2018-01-10

- Vladimir Sementsov-Ogievskiy: nbd: rename nbd_option and nbd_opt_reply
- Vladimir Sementsov-Ogievskiy: nbd/server: add additional assert to nbd_export_put

# gpg: Signature made Wed 10 Jan 2018 22:53:49 GMT
# gpg:                using RSA key 0xA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>"
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>"
# gpg:                 aka "[jpeg image of size 6874]"
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2018-01-10:
  nbd: rename nbd_option and nbd_opt_reply
  nbd/server: add additional assert to nbd_export_put

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

3 files changed, 16 insertions, 10 deletions

diff --git a/include/block/nbd.h b/include/block/nbd.h
index 113c707a5e..978e443366 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -28,20 +28,20 @@
 
 /* Handshake phase structs - this struct is passed on the wire */
 
-struct nbd_option {
+struct NBDOption {
     uint64_t magic; /* NBD_OPTS_MAGIC */
     uint32_t option; /* NBD_OPT_* */
     uint32_t length;
 } QEMU_PACKED;
-typedef struct nbd_option nbd_option;
+typedef struct NBDOption NBDOption;
 
-struct nbd_opt_reply {
+struct NBDOptionReply {
     uint64_t magic; /* NBD_REP_MAGIC */
     uint32_t option; /* NBD_OPT_* */
     uint32_t type; /* NBD_REP_* */
     uint32_t length;
 } QEMU_PACKED;
-typedef struct nbd_opt_reply nbd_opt_reply;
+typedef struct NBDOptionReply NBDOptionReply;
 
 /* Transmission phase structs
  *
diff --git a/nbd/client.c b/nbd/client.c
index eea236ca06..89f80f9590 100644
--- a/nbd/client.c
+++ b/nbd/client.c
@@ -66,7 +66,7 @@ static int nbd_send_option_request(QIOChannel *ioc, uint32_t opt,
                                    uint32_t len, const char *data,
                                    Error **errp)
 {
-    nbd_option req;
+    NBDOption req;
     QEMU_BUILD_BUG_ON(sizeof(req) != 16);
 
     if (len == -1) {
@@ -109,7 +109,7 @@ static void nbd_send_opt_abort(QIOChannel *ioc)
  * payload. Return 0 if successful, -1 with errp set if it is
  * impossible to continue. */
 static int nbd_receive_option_reply(QIOChannel *ioc, uint32_t opt,
-                                    nbd_opt_reply *reply, Error **errp)
+                                    NBDOptionReply *reply, Error **errp)
 {
     QEMU_BUILD_BUG_ON(sizeof(*reply) != 20);
     if (nbd_read(ioc, reply, sizeof(*reply), errp) < 0) {
@@ -146,7 +146,7 @@ static int nbd_receive_option_reply(QIOChannel *ioc, uint32_t opt,
  * can fall back to other approaches), or -1 with errp set for other
  * errors.
  */
-static int nbd_handle_reply_err(QIOChannel *ioc, nbd_opt_reply *reply,
+static int nbd_handle_reply_err(QIOChannel *ioc, NBDOptionReply *reply,
                                 Error **errp)
 {
     char *msg = NULL;
@@ -239,7 +239,7 @@ static int nbd_handle_reply_err(QIOChannel *ioc, nbd_opt_reply *reply,
 static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match,
                             Error **errp)
 {
-    nbd_opt_reply reply;
+    NBDOptionReply reply;
     uint32_t len;
     uint32_t namelen;
     char name[NBD_MAX_NAME_SIZE + 1];
@@ -325,7 +325,7 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match,
 static int nbd_opt_go(QIOChannel *ioc, const char *wantname,
                       NBDExportInfo *info, Error **errp)
 {
-    nbd_opt_reply reply;
+    NBDOptionReply reply;
     uint32_t len = strlen(wantname);
     uint16_t type;
     int error;
@@ -517,7 +517,7 @@ static int nbd_receive_query_exports(QIOChannel *ioc,
  */
 static int nbd_request_simple_option(QIOChannel *ioc, int opt, Error **errp)
 {
-    nbd_opt_reply reply;
+    NBDOptionReply reply;
     int error;
 
     if (nbd_send_option_request(ioc, opt, 0, NULL, errp) < 0) {
diff --git a/nbd/server.c b/nbd/server.c
index e443b3cf5c..6cf2eeb2c1 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -1190,6 +1190,12 @@ void nbd_export_put(NBDExport *exp)
         nbd_export_close(exp);
     }
 
+    /* nbd_export_close() may theoretically reduce refcount to 0. It may happen
+     * if someone calls nbd_export_put() on named export not through
+     * nbd_export_set_name() when refcount is 1. So, let's assert that
+     * it is > 0.
+     */
+    assert(exp->refcount > 0);
     if (--exp->refcount == 0) {
         assert(exp->name == NULL);
         assert(exp->description == NULL);