cifs: convert send_nt_cancel into a version specific op

For SMB2, this should be a no-op. Obviously if we wanted to do something
for the SMB2 case, we could also define an operation here for it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>

1 files changed, 8 insertions, 38 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 0961336513d5..269a5a7e0030 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -483,41 +483,11 @@ cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
         return rc;
 }
 
-/*
- * An NT cancel request header looks just like the original request except:
- *
- * The Command is SMB_COM_NT_CANCEL
- * The WordCount is zeroed out
- * The ByteCount is zeroed out
- *
- * This function mangles an existing request buffer into a
- * SMB_COM_NT_CANCEL request and then sends it.
- */
-static int
-send_nt_cancel(struct TCP_Server_Info *server, struct smb_hdr *in_buf,
-                struct mid_q_entry *mid)
+static inline int
+send_cancel(struct TCP_Server_Info *server, void *buf, struct mid_q_entry *mid)
 {
-        int rc = 0;
-
-        /* -4 for RFC1001 length and +2 for BCC field */
-        in_buf->smb_buf_length = cpu_to_be32(sizeof(struct smb_hdr) - 4  + 2);
-        in_buf->Command = SMB_COM_NT_CANCEL;
-        in_buf->WordCount = 0;
-        put_bcc(0, in_buf);
-
-        mutex_lock(&server->srv_mutex);
-        rc = cifs_sign_smb(in_buf, server, &mid->sequence_number);
-        if (rc) {
-                mutex_unlock(&server->srv_mutex);
-                return rc;
-        }
-        rc = smb_send(server, in_buf, be32_to_cpu(in_buf->smb_buf_length));
-        mutex_unlock(&server->srv_mutex);
-
-        cFYI(1, "issued NT_CANCEL for mid %u, rc = %d",
-                in_buf->Mid, rc);
-
-        return rc;
+        return server->ops->send_cancel ?
+                                server->ops->send_cancel(server, buf, mid) : 0;
 }
 
 int
@@ -636,7 +606,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 
         rc = wait_for_response(ses->server, midQ);
         if (rc != 0) {
-                send_nt_cancel(ses->server, (struct smb_hdr *)buf, midQ);
+                send_cancel(ses->server, buf, midQ);
                 spin_lock(&GlobalMid_Lock);
                 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
                         midQ->callback = DeleteMidQEntry;
@@ -753,7 +723,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 
         rc = wait_for_response(ses->server, midQ);
         if (rc != 0) {
-                send_nt_cancel(ses->server, in_buf, midQ);
+                send_cancel(ses->server, in_buf, midQ);
                 spin_lock(&GlobalMid_Lock);
                 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
                         /* no longer considered to be "in-flight" */
@@ -898,7 +868,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
                 if (in_buf->Command == SMB_COM_TRANSACTION2) {
                         /* POSIX lock. We send a NT_CANCEL SMB to cause the
                            blocking lock to return. */
-                        rc = send_nt_cancel(ses->server, in_buf, midQ);
+                        rc = send_cancel(ses->server, in_buf, midQ);
                         if (rc) {
                                 delete_mid(midQ);
                                 return rc;
@@ -919,7 +889,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
 
                 rc = wait_for_response(ses->server, midQ);
                 if (rc) {
-                        send_nt_cancel(ses->server, in_buf, midQ);
+                        send_cancel(ses->server, in_buf, midQ);
                         spin_lock(&GlobalMid_Lock);
                         if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
                                 /* no longer considered to be "in-flight" */