libceph: socket can close in any connection state

A connection's socket can close for any reason, independent of the
state of the connection (and without irrespective of the connection
mutex).  As a result, the connectino can be in pretty much any state
at the time its socket is closed.

Handle those other cases at the top of con_work().  Pull this whole
block of code into a separate function to reduce the clutter.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

1 files changed, 30 insertions, 17 deletions

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 1041114453db..4b04ccc60db1 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -2273,6 +2273,35 @@ static void queue_con(struct ceph_connection *con)
         (void) queue_con_delay(con, 0);
 }
 
+static bool con_sock_closed(struct ceph_connection *con)
+{
+        if (!test_and_clear_bit(CON_FLAG_SOCK_CLOSED, &con->flags))
+                return false;
+
+#define CASE(x)                                                         \
+        case CON_STATE_ ## x:                                           \
+                con->error_msg = "socket closed (con state " #x ")";    \
+                break;
+
+        switch (con->state) {
+        CASE(CLOSED);
+        CASE(PREOPEN);
+        CASE(CONNECTING);
+        CASE(NEGOTIATING);
+        CASE(OPEN);
+        CASE(STANDBY);
+        default:
+                pr_warning("%s con %p unrecognized state %lu\n",
+                        __func__, con, con->state);
+                con->error_msg = "unrecognized con state";
+                BUG();
+                break;
+        }
+#undef CASE
+
+        return true;
+}
+
 /*
  * Do some work on a connection.  Drop a connection ref when we're done.
  */
@@ -2284,24 +2313,8 @@ static void con_work(struct work_struct *work)
 
         mutex_lock(&con->mutex);
 restart:
-        if (test_and_clear_bit(CON_FLAG_SOCK_CLOSED, &con->flags)) {
-                switch (con->state) {
-                case CON_STATE_CONNECTING:
-                        con->error_msg = "connection failed";
-                        break;
-                case CON_STATE_NEGOTIATING:
-                        con->error_msg = "negotiation failed";
-                        break;
-                case CON_STATE_OPEN:
-                        con->error_msg = "socket closed";
-                        break;
-                default:
-                        dout("unrecognized con state %d\n", (int)con->state);
-                        con->error_msg = "unrecognized con state";
-                        BUG();
-                }
+        if (con_sock_closed(con))
                 goto fault;
-        }
 
         if (test_and_clear_bit(CON_FLAG_BACKOFF, &con->flags)) {
                 dout("con_work %p backing off\n", con);