nbd: Introduce NBD named exports.

This patch allows to connect Qemu using NBD protocol to an nbd-server
using named exports.

For instance, if on the host "isoserver", in /etc/nbd-server/config, you have:

[generic]
[debian-500-ppc-netinst]
        exportname = /ISO/debian-500-powerpc-netinst.iso
[Fedora-10-ppc-netinst]
        exportname = /ISO/Fedora-10-ppc-netinst.iso

You can connect to it, using:

    qemu -cdrom nbd:isoserver:exportname=debian-500-ppc-netinst
    qemu -cdrom nbd:isoserver:exportname=Fedora-10-ppc-netinst

NOTE: you need at least nbd-server 2.9.18

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/nbd.h b/nbd.h
index 5a1fbdf512..8ff65a1941 100644
--- a/nbd.h
+++ b/nbd.h
@@ -42,6 +42,8 @@ enum {
     NBD_CMD_DISC = 2
 };
 
+#define NBD_DEFAULT_PORT	10809
+
 size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read);
 int tcp_socket_outgoing(const char *address, uint16_t port);
 int tcp_socket_incoming(const char *address, uint16_t port);
@@ -49,7 +51,8 @@ int unix_socket_outgoing(const char *path);
 int unix_socket_incoming(const char *path);
 
 int nbd_negotiate(int csock, off_t size);
-int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize);
+int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags,
+                          off_t *size, size_t *blocksize);
 int nbd_init(int fd, int csock, off_t size, size_t blocksize);
 int nbd_send_request(int csock, struct nbd_request *request);
 int nbd_receive_reply(int csock, struct nbd_reply *reply);