[Qemu-devel] [PULL 0/2] nbd patches for 10 Jan

[Qemu-devel] [PULL 0/2] nbd patches for 10 Jan

[Eric Blake]

The following changes since commit 3cee4db661ab9c0fce7937b3bbfa188a1845f31f:

  Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2018-01-08' into staging (2018-01-09 15:22:47 +0000)

are available in the Git repository at:

  git://repo.or.cz/qemu/ericb.git tags/pull-nbd-2018-01-10

for you to fetch changes up to 420a4e955909788263a33d11600839e93480dfd3:

  nbd: rename nbd_option and nbd_opt_reply (2018-01-10 12:11:23 -0600)

Not much time elapsed since my last pull request, but my last request
was delayed due the holiday break, and I've now got other patches that
will be easier to post if I can do a Based-on: against this pull request,
rather than the larger in-progress series they were extracted from.

----------------------------------------------------------------
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

----------------------------------------------------------------
Vladimir Sementsov-Ogievskiy (2):
      nbd/server: add additional assert to nbd_export_put
      nbd: rename nbd_option and nbd_opt_reply

 include/block/nbd.h |  8 ++++----
 nbd/client.c        | 12 ++++++------
 nbd/server.c        |  6 ++++++
 3 files changed, 16 insertions(+), 10 deletions(-)

-- 
2.14.3

[Qemu-devel] [PULL 1/2] nbd/server: add additional assert to nbd_export_put

[Eric Blake]

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

This place is not obvious, 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.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20171207155102.66622-2-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 nbd/server.c | 6 ++++++
 1 file changed, 6 insertions(+)

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);
-- 
2.14.3

[Qemu-devel] [PULL 2/2] nbd: rename nbd_option and nbd_opt_reply

[Eric Blake]

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

Rename nbd_option and nbd_opt_reply to NBDOption and NBDOptionReply
to correspond to Qemu coding style and other structures here.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171122101958.17065-5-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 include/block/nbd.h |  8 ++++----
 nbd/client.c        | 12 ++++++------
 2 files changed, 10 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) {
-- 
2.14.3

Re: [Qemu-devel] [PULL 0/2] nbd patches for 10 Jan

[Peter Maydell]

On 10 January 2018 at 22:59, Eric Blake <eblake@redhat.com> wrote:
> The following changes since commit 3cee4db661ab9c0fce7937b3bbfa188a1845f31f:
>
>   Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2018-01-08' into staging (2018-01-09 15:22:47 +0000)
>
> are available in the Git repository at:
>
>   git://repo.or.cz/qemu/ericb.git tags/pull-nbd-2018-01-10
>
> for you to fetch changes up to 420a4e955909788263a33d11600839e93480dfd3:
>
>   nbd: rename nbd_option and nbd_opt_reply (2018-01-10 12:11:23 -0600)
>
> Not much time elapsed since my last pull request, but my last request
> was delayed due the holiday break, and I've now got other patches that
> will be easier to post if I can do a Based-on: against this pull request,
> rather than the larger in-progress series they were extracted from.
>
> ----------------------------------------------------------------
> 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
>
> ----------------------------------------------------------------

Applied, thanks.

-- PMM