cifs: add ability to send an echo request
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 3652cc6..54b9f5d 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -706,6 +706,53 @@
return rc;
}
+/*
+ * This is a no-op for now. We're not really interested in the reply, but
+ * rather in the fact that the server sent one and that server->lstrp
+ * gets updated.
+ *
+ * FIXME: maybe we should consider checking that the reply matches request?
+ */
+static void
+cifs_echo_callback(struct mid_q_entry *mid)
+{
+ struct TCP_Server_Info *server = mid->callback_data;
+
+ DeleteMidQEntry(mid);
+ atomic_dec(&server->inFlight);
+ wake_up(&server->request_q);
+}
+
+int
+CIFSSMBEcho(struct TCP_Server_Info *server)
+{
+ ECHO_REQ *smb;
+ int rc = 0;
+
+ cFYI(1, "In echo request");
+
+ rc = small_smb_init(SMB_COM_ECHO, 0, NULL, (void **)&smb);
+ if (rc)
+ return rc;
+
+ /* set up echo request */
+ smb->hdr.Tid = cpu_to_le16(0xffff);
+ smb->hdr.WordCount = cpu_to_le16(1);
+ smb->EchoCount = cpu_to_le16(1);
+ smb->ByteCount = cpu_to_le16(1);
+ smb->Data[0] = 'a';
+ smb->hdr.smb_buf_length += 3;
+
+ rc = cifs_call_async(server, (struct smb_hdr *)smb,
+ cifs_echo_callback, server);
+ if (rc)
+ cFYI(1, "Echo request failed: %d", rc);
+
+ cifs_small_buf_release(smb);
+
+ return rc;
+}
+
int
CIFSSMBLogoff(const int xid, struct cifsSesInfo *ses)
{