Fix reconnect to not defer smb3 session reconnect long after socket reconnect

commit 4fcd1813e6404dd4420c7d12fb483f9320f0bf93 upstream.

Azure server blocks clients that open a socket and don't do anything on it.
In our reconnect scenarios, we can reconnect the tcp session and
detect the socket is available but we defer the negprot and SMB3 session
setup and tree connect reconnection until the next i/o is requested, but
this looks suspicous to some servers who expect SMB3 negprog and session
setup soon after a socket is created.

In the echo thread, reconnect SMB3 sessions and tree connections
that are disconnected.  A later patch will replay persistent (and
resilient) handle opens.

Signed-off-by: Steve French <steve.french@primarydata.com>
Acked-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 6f62ac821a8459228e50d7a4261482dd4b0d4abe..34cbc582e8d701e463bcf51f87c34391e6a9b1cf 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -428,7 +428,9 @@ cifs_echo_request(struct work_struct *work)
         * server->ops->need_neg() == true. Also, no need to ping if
         * we got a response recently.
         */
-       if (!server->ops->need_neg || server->ops->need_neg(server) ||
+
+       if (server->tcpStatus == CifsNeedReconnect ||
+           server->tcpStatus == CifsExiting || server->tcpStatus == CifsNew ||
            (server->ops->can_echo && !server->ops->can_echo(server)) ||
            time_before(jiffies, server->lstrp + echo_interval - HZ))
                goto requeue_echo;

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 8f38e33d365bcca5ce9079dc64e5d10525df801c..f2cbb281c44a89b14dffabc99b6c2766dda9bdcc 100644 (file)
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1818,6 +1818,33 @@ SMB2_echo(struct TCP_Server_Info *server)
 
        cifs_dbg(FYI, "In echo request\n");
 
+       if (server->tcpStatus == CifsNeedNegotiate) {
+               struct list_head *tmp, *tmp2;
+               struct cifs_ses *ses;
+               struct cifs_tcon *tcon;
+
+               cifs_dbg(FYI, "Need negotiate, reconnecting tcons\n");
+               spin_lock(&cifs_tcp_ses_lock);
+               list_for_each(tmp, &server->smb_ses_list) {
+                       ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
+                       list_for_each(tmp2, &ses->tcon_list) {
+                               tcon = list_entry(tmp2, struct cifs_tcon,
+                                                 tcon_list);
+                               /* add check for persistent handle reconnect */
+                               if (tcon && tcon->need_reconnect) {
+                                       spin_unlock(&cifs_tcp_ses_lock);
+                                       rc = smb2_reconnect(SMB2_ECHO, tcon);
+                                       spin_lock(&cifs_tcp_ses_lock);
+                               }
+                       }
+               }
+               spin_unlock(&cifs_tcp_ses_lock);
+       }
+
+       /* if no session, renegotiate failed above */
+       if (server->tcpStatus == CifsNeedNegotiate)
+               return -EIO;
+
        rc = small_smb2_init(SMB2_ECHO, NULL, (void **)&req);
        if (rc)
                return rc;