From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Date: Wed, 3 Oct 2018 14:47:38 +0000 (+0300)
Subject: nbd/server: fix NBD_CMD_CACHE
X-Git-Tag: qemu-xen-4.12.1^2~53
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=92c7eec10926eaff161a91624f399b4afe6cb273;p=qemu-xen.git

nbd/server: fix NBD_CMD_CACHE

We should not go to structured-read branch on CACHE command, fix that.

Bug introduced in bc37b06a5cde24 "nbd/server: introduce NBD_CMD_CACHE"
with the whole feature and affects 3.0.0 release.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
CC: qemu-stable@nongnu.org
Message-Id: <20181003144738.70670-1-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: commit message typo fix]
Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 2f454defc23e1be78f2a96bad2877ce7829f61b4)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---

diff --git a/nbd/server.c b/nbd/server.c
index 12f721482d..adcba66aa9 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -2138,7 +2138,8 @@ static coroutine_fn int nbd_do_cmd_read(NBDClient *client, NBDRequest *request,
     }
 
     if (client->structured_reply && !(request->flags & NBD_CMD_FLAG_DF) &&
-        request->len) {
+        request->len && request->type != NBD_CMD_CACHE)
+    {
         return nbd_co_send_sparse_read(client, request->handle, request->from,
                                        data, request->len, errp);
     }