Merge remote-tracking branch 'bonzini/nbd-next' into staging

* bonzini/nbd-next:
  nbd: fixes to read-only handling
  hmp: add NBD server commands
  nbd: disallow nbd-server-add before nbd-server-start
  nbd: force read-only export for read-only devices
  nbd: fix nbd_server_stop crash when no server was running
  nbd: accept URIs
  nbd: accept relative path to Unix socket
  qemu-nbd: initialize main loop before block layer

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 12 insertions, 13 deletions

diff --git a/nbd.c b/nbd.c
index cec5a9449b..97a5914e0f 100644
--- a/nbd.c
+++ b/nbd.c
@@ -596,24 +596,23 @@ int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize)
         return -serrno;
     }
 
-    if (flags & NBD_FLAG_READ_ONLY) {
-        int read_only = 1;
-        TRACE("Setting readonly attribute");
-
-        if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
+    if (ioctl(fd, NBD_SET_FLAGS, flags) < 0) {
+        if (errno == ENOTTY) {
+            int read_only = (flags & NBD_FLAG_READ_ONLY) != 0;
+            TRACE("Setting readonly attribute");
+
+            if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
+                int serrno = errno;
+                LOG("Failed setting read-only attribute");
+                return -serrno;
+            }
+        } else {
             int serrno = errno;
-            LOG("Failed setting read-only attribute");
+            LOG("Failed setting flags");
             return -serrno;
         }
     }
 
-    if (ioctl(fd, NBD_SET_FLAGS, flags) < 0
-        && errno != ENOTTY) {
-        int serrno = errno;
-        LOG("Failed setting flags");
-        return -serrno;
-    }
-
     TRACE("Negotiation ended");
 
     return 0;