X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;ds=sidebyside;f=src%2Fvcl%2Fvppcom.c;h=8c2036ca2868bb80ff1aaa0b347a21c48475f36f;hb=dcf55ce28d558ddeb1fd93904b54dbb843430a0f;hp=71d5af0446dda59494e9d8eb10028d81b8601bd9;hpb=498b3a56c9b61582b237614193920be610eaca58;p=vpp.git

diff --git a/src/vcl/vppcom.c b/src/vcl/vppcom.c
index 71d5af0446d..8c2036ca286 100644
--- a/src/vcl/vppcom.c
+++ b/src/vcl/vppcom.c
@@ -83,6 +83,7 @@ typedef struct
   u32 vep_idx;
   vppcom_epoll_event_t ev;
 #define VEP_DEFAULT_ET_MASK  (EPOLLIN|EPOLLOUT)
+#define VEP_UNSUPPORTED_EVENTS (EPOLLONESHOT|EPOLLEXCLUSIVE)
   u32 et_mask;
 } vppcom_epoll_t;
 
@@ -98,8 +99,10 @@ typedef struct
 
   svm_fifo_t *server_rx_fifo;
   svm_fifo_t *server_tx_fifo;
+  u8 *segment_name;
   u32 sm_seg_index;
-  u64 vpp_session_handle;
+  u32 client_context;
+  u64 vpp_handle;
   unix_shared_memory_queue_t *vpp_event_queue;
 
   /* Socket configuration state */
@@ -199,6 +202,22 @@ static vppcom_main_t _vppcom_main = {
 
 static vppcom_main_t *vcm = &_vppcom_main;
 
+#define VCL_LOCK_AND_GET_SESSION(I, S)                  \
+do {                                                    \
+  clib_spinlock_lock (&vcm->sessions_lockp);            \
+  rv = vppcom_session_at_index (I, S);                  \
+  if (PREDICT_FALSE (rv))                               \
+    {                                                   \
+      clib_spinlock_unlock (&vcm->sessions_lockp);      \
+                                                        \
+      if (VPPCOM_DEBUG > 0)                             \
+        clib_warning ("[%s] ERROR: Invalid ##I (%u)!",  \
+                      getpid (), I);                  \
+                                                        \
+      goto done;                                        \
+    }                                                   \
+} while (0)
+
 static const char *
 vppcom_app_state_str (app_state_t state)
 {
@@ -287,6 +306,46 @@ vppcom_session_at_index (u32 session_index, session_t * volatile *sess)
   return VPPCOM_OK;
 }
 
+static inline void
+vppcom_session_table_add_listener (u64 listener_handle, u32 value)
+{
+  /* Session and listener handles have different formats. The latter has
+   * the thread index in the upper 32 bits while the former has the session
+   * type. Knowing that, for listeners we just flip the MSB to 1 */
+  listener_handle |= 1ULL << 63;
+  hash_set (vcm->session_index_by_vpp_handles, listener_handle, value);
+}
+
+static inline session_t *
+vppcom_session_table_lookup_listener (u64 listener_handle)
+{
+  uword *p;
+  u64 handle = listener_handle | (1ULL << 63);
+  p = hash_get (vcm->session_index_by_vpp_handles, handle);
+  if (!p)
+    {
+      clib_warning ("[%d] couldn't find listen session: unknown vpp "
+		    "listener handle %llx", getpid (), listener_handle);
+      return 0;
+    }
+  if (pool_is_free_index (vcm->sessions, p[0]))
+    {
+      if (VPPCOM_DEBUG > 1)
+	clib_warning ("[%d] invalid listen session, sid (%u)", getpid (),
+		      p[0]);
+      return 0;
+    }
+
+  return pool_elt_at_index (vcm->sessions, p[0]);
+}
+
+static inline void
+vppcom_session_table_del_listener (u64 listener_handle)
+{
+  listener_handle |= 1ULL << 63;
+  hash_unset (vcm->session_index_by_vpp_handles, listener_handle);
+}
+
 static int
 vppcom_connect_to_vpp (char *app_name)
 {
@@ -580,33 +639,44 @@ vl_api_disconnect_session_reply_t_handler (vl_api_disconnect_session_reply_t *
 					   mp)
 {
   uword *p;
+  u32 session_index = ~0;
 
   p = hash_get (vcm->session_index_by_vpp_handles, mp->handle);
   if (p)
     {
       session_t *session = 0;
       int rv;
+
+      session_index = p[0];
+      hash_unset (vcm->session_index_by_vpp_handles, mp->handle);
       clib_spinlock_lock (&vcm->sessions_lockp);
-      rv = vppcom_session_at_index (p[0], &session);
+      rv = vppcom_session_at_index (session_index, &session);
       if (PREDICT_FALSE (rv))
 	{
 	  if (VPPCOM_DEBUG > 1)
-	    clib_warning ("[%d] invalid session, sid (%u) has been closed!",
-			  getpid (), p[0]);
+	    clib_warning ("[%d] invalid session, sid %u has been closed!",
+			  getpid (), session_index);
+	}
+      else
+	{
+	  if (VPPCOM_DEBUG > 1)
+	    clib_warning ("[%d] vpp handle 0x%llx, sid %u disconnected!",
+			  getpid (), mp->handle, session_index);
+
+	  session->state = STATE_DISCONNECT;
 	}
-      hash_unset (vcm->session_index_by_vpp_handles, mp->handle);
-      session->state = STATE_DISCONNECT;
       clib_spinlock_unlock (&vcm->sessions_lockp);
     }
   else
     {
       if (VPPCOM_DEBUG > 1)
-	clib_warning ("[%d] couldn't find session key %llx", getpid (),
-		      mp->handle);
+	clib_warning ("[%d] couldn't find session: unknown vpp handle 0x%llx",
+		      getpid (), mp->handle);
     }
 
   if (mp->retval)
-    clib_warning ("[%d] disconnect_session failed: %U", getpid (),
+    clib_warning ("[%d] disconnect_session vpp handle 0x%llx, sid %u "
+		  "failed: %U", getpid (), mp->handle, session_index,
 		  format_api_error, ntohl (mp->retval));
 }
 
@@ -640,12 +710,26 @@ vl_api_disconnect_session_t_handler (vl_api_disconnect_session_t * mp)
   session_t *session = 0;
   vl_api_disconnect_session_reply_t *rmp;
   uword *p;
-  int rv = 0;
+  int rv = 0, rval;
 
   p = hash_get (vcm->session_index_by_vpp_handles, mp->handle);
+  if (VPPCOM_DEBUG > 0)
+    {
+      if (!p)
+	{
+	  clib_warning ("[%d] request to disconnect invalid handle (%u)!",
+			getpid (), mp->handle);
+	  rv = -11;
+	  goto done;
+	}
+      clib_warning ("[%d] disconnecting handle %u sid (%u)!", getpid (),
+		    mp->handle, p[0]);
+    }
+
+  goto done;
+
   if (p)
     {
-      int rval;
       clib_spinlock_lock (&vcm->sessions_lockp);
       rval = vppcom_session_at_index (p[0], &session);
       if (PREDICT_FALSE (rval))
@@ -661,11 +745,12 @@ vl_api_disconnect_session_t_handler (vl_api_disconnect_session_t * mp)
     }
   else
     {
-      clib_warning ("[%d] couldn't find session key %llx", getpid (),
-		    mp->handle);
+      clib_warning ("[%d] couldn't find session: unknown vpp handle 0x%llx",
+		    getpid (), mp->handle);
       rv = -11;
     }
 
+done:
   rmp = vl_msg_api_alloc (sizeof (*rmp));
   memset (rmp, 0, sizeof (*rmp));
 
@@ -702,8 +787,8 @@ vl_api_reset_session_t_handler (vl_api_reset_session_t * mp)
     }
   else
     {
-      clib_warning ("[%d] couldn't find session key %llx", getpid (),
-		    mp->handle);
+      clib_warning ("[%d] couldn't find session: unknown vpp handle 0x%llx",
+		    getpid (), mp->handle);
       rv = -11;
     }
 
@@ -756,8 +841,9 @@ vl_api_connect_session_reply_t_handler (vl_api_connect_session_reply_t * mp)
       memset (a, 0, sizeof (*a));
       a->segment_name = (char *) mp->segment_name;
       if (VPPCOM_DEBUG > 1)
-	clib_warning ("[%d] cut-thru segment: %s", getpid (),
-		      a->segment_name);
+	clib_warning ("[%d] cut-thru segment: %s\n",
+		      getpid (), a->segment_name);
+
       rv = svm_fifo_segment_attach (a);
       vec_reset_length (a->new_segment_indices);
       if (PREDICT_FALSE (rv))
@@ -772,9 +858,6 @@ vl_api_connect_session_reply_t_handler (vl_api_connect_session_reply_t * mp)
   /*
    * Setup session
    */
-  if (VPPCOM_DEBUG > 1)
-    clib_warning ("[%d] client sid %d", getpid (), session_index);
-
   session = pool_elt_at_index (vcm->sessions, session_index);
   session->is_cut_thru = is_cut_thru;
   session->vpp_event_queue = uword_to_pointer (mp->vpp_event_queue_address,
@@ -787,11 +870,21 @@ vl_api_connect_session_reply_t_handler (vl_api_connect_session_reply_t * mp)
 
   session->server_rx_fifo = rx_fifo;
   session->server_tx_fifo = tx_fifo;
-  session->vpp_session_handle = mp->handle;
+  session->vpp_handle = mp->handle;
   session->state = STATE_CONNECT;
 
   /* Add it to lookup table */
   hash_set (vcm->session_index_by_vpp_handles, mp->handle, session_index);
+
+  if (VPPCOM_DEBUG > 1)
+    clib_warning ("[%d] client sid %d, vpp handle 0x%llx\n"
+		  "  session_rx_fifo %p, refcnt %d\n"
+		  "  session_tx_fifo %p, refcnt %d",
+		  getpid (), session_index, mp->handle,
+		  session->server_rx_fifo,
+		  session->server_rx_fifo->refcnt,
+		  session->server_tx_fifo, session->server_tx_fifo->refcnt);
+
   clib_spinlock_unlock (&vcm->sessions_lockp);
 }
 
@@ -831,7 +924,7 @@ vppcom_send_disconnect (session_t * session)
   memset (dmp, 0, sizeof (*dmp));
   dmp->_vl_msg_id = ntohs (VL_API_DISCONNECT_SESSION);
   dmp->client_index = vcm->my_client_index;
-  dmp->handle = session->vpp_session_handle;
+  dmp->handle = session->vpp_handle;
   vl_msg_api_send_shmem (vcm->vl_input_queue, (u8 *) & dmp);
 }
 
@@ -851,9 +944,12 @@ vl_api_bind_sock_reply_t_handler (vl_api_bind_sock_reply_t * mp)
   rv = vppcom_session_at_index (vcm->bind_session_index, &session);
   if (rv == VPPCOM_OK)
     {
-      session->vpp_session_handle = mp->handle;
-      hash_set (vcm->session_index_by_vpp_handles, mp->handle,
-		vcm->bind_session_index);
+      session->vpp_handle = mp->handle;
+      session->lcl_addr.is_ip4 = mp->lcl_is_ip4;
+      clib_memcpy (&session->lcl_addr.ip46, mp->lcl_ip,
+		   sizeof (session->peer_addr.ip46));
+      session->lcl_port = mp->lcl_port;
+      vppcom_session_table_add_listener (mp->handle, vcm->bind_session_index);
       session->state = mp->retval ? STATE_FAILED : STATE_LISTEN;
       vcm->bind_session_index = ~0;
     }
@@ -864,16 +960,17 @@ static void
 vl_api_unbind_sock_reply_t_handler (vl_api_unbind_sock_reply_t * mp)
 {
   session_t *session = 0;
-  int rv;
 
   clib_spinlock_lock (&vcm->sessions_lockp);
-  rv = vppcom_session_at_index (vcm->bind_session_index, &session);
-  if (rv == VPPCOM_OK)
+  session = vppcom_session_table_lookup_listener (vcm->bind_session_index);
+
+  if (session)
     {
       if ((VPPCOM_DEBUG > 1) && (mp->retval))
 	clib_warning ("[%d] unbind failed: %U", getpid (), format_api_error,
 		      ntohl (mp->retval));
 
+      vppcom_session_table_del_listener (vcm->bind_session_index);
       vcm->bind_session_index = ~0;
       session->state = STATE_START;
     }
@@ -963,31 +1060,45 @@ format_ip46_address (u8 * s, va_list * args)
     format (s, "%U", format_ip6_address, &ip46->ip6);
 }
 
+static inline void
+vppcom_send_accept_session_reply (u32 handle, int retval)
+{
+  vl_api_accept_session_reply_t *rmp;
+
+  rmp = vl_msg_api_alloc (sizeof (*rmp));
+  memset (rmp, 0, sizeof (*rmp));
+  rmp->_vl_msg_id = ntohs (VL_API_ACCEPT_SESSION_REPLY);
+  rmp->retval = htonl (retval);
+  rmp->handle = handle;
+  vl_msg_api_send_shmem (vcm->vl_input_queue, (u8 *) & rmp);
+}
+
 static void
 vl_api_accept_session_t_handler (vl_api_accept_session_t * mp)
 {
-  vl_api_accept_session_reply_t *rmp;
   svm_fifo_t *rx_fifo, *tx_fifo;
-  session_t *session;
+  session_t *session, *listen_session;
   u32 session_index;
-  int rv = 0;
 
+  clib_spinlock_lock (&vcm->sessions_lockp);
   if (!clib_fifo_free_elts (vcm->client_session_index_fifo))
     {
       clib_warning ("[%d] client session queue is full!", getpid ());
-      rv = VNET_API_ERROR_QUEUE_FULL;
-      goto send_reply;
+      vppcom_send_accept_session_reply (mp->handle,
+					VNET_API_ERROR_QUEUE_FULL);
+      clib_spinlock_unlock (&vcm->sessions_lockp);
+      return;
     }
 
-  if (VPPCOM_DEBUG > 1)
+  listen_session = vppcom_session_table_lookup_listener (mp->listener_handle);
+  if (!listen_session)
     {
-      u8 *ip_str = format (0, "%U", format_ip46_address, &mp->ip, mp->is_ip4);
-      clib_warning ("[%d] accepted session from: %s:%d", getpid (), ip_str,
-		    clib_net_to_host_u16 (mp->port));
-      vec_free (ip_str);
+      clib_warning ("[%d] ERROR: couldn't find listen session: unknown vpp "
+		    "listener handle %llx", getpid (), mp->listener_handle);
+      clib_spinlock_unlock (&vcm->sessions_lockp);
+      return;
     }
 
-  clib_spinlock_lock (&vcm->sessions_lockp);
   /* Allocate local session and set it up */
   pool_get (vcm->sessions, session);
   memset (session, 0, sizeof (*session));
@@ -998,6 +1109,7 @@ vl_api_accept_session_t_handler (vl_api_accept_session_t * mp)
   tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
   tx_fifo->client_session_index = session_index;
 
+  session->vpp_handle = mp->handle;
   session->server_rx_fifo = rx_fifo;
   session->server_tx_fifo = tx_fifo;
   session->vpp_event_queue = uword_to_pointer (mp->vpp_event_queue_address,
@@ -1012,20 +1124,53 @@ vl_api_accept_session_t_handler (vl_api_accept_session_t * mp)
 
   /* Add it to lookup table */
   hash_set (vcm->session_index_by_vpp_handles, mp->handle, session_index);
+  session->lcl_port = listen_session->lcl_port;
+  session->lcl_addr = listen_session->lcl_addr;
 
+  /* TBD: move client_session_index_fifo into listener session */
   clib_fifo_add1 (vcm->client_session_index_fifo, session_index);
+
   clib_spinlock_unlock (&vcm->sessions_lockp);
 
-  /*
-   * Send accept reply to vpp
-   */
-send_reply:
+  if (VPPCOM_DEBUG > 1)
+    {
+      u8 *ip_str = format (0, "%U", format_ip46_address, &mp->ip, mp->is_ip4);
+      clib_warning ("[%d] received request to accept session (sid %d) "
+		    "from %s:%d", getpid (), session_index, ip_str,
+		    clib_net_to_host_u16 (mp->port));
+      vec_free (ip_str);
+    }
+}
+
+static void
+vppcom_send_connect_session_reply (session_t * session, int retval)
+{
+  vl_api_connect_session_reply_t *rmp;
+  u32 len;
+  unix_shared_memory_queue_t *client_q;
+
   rmp = vl_msg_api_alloc (sizeof (*rmp));
   memset (rmp, 0, sizeof (*rmp));
-  rmp->_vl_msg_id = ntohs (VL_API_ACCEPT_SESSION_REPLY);
-  rmp->retval = htonl (rv);
-  rmp->handle = mp->handle;
-  vl_msg_api_send_shmem (vcm->vl_input_queue, (u8 *) & rmp);
+
+  rmp->_vl_msg_id = ntohs (VL_API_CONNECT_SESSION_REPLY);
+  rmp->context = session->client_context;
+  rmp->retval = htonl (retval);
+  rmp->handle = session->vpp_handle;
+  rmp->server_rx_fifo = pointer_to_uword (session->server_rx_fifo);
+  rmp->server_tx_fifo = pointer_to_uword (session->server_tx_fifo);
+  rmp->vpp_event_queue_address = pointer_to_uword (session->vpp_event_queue);
+  rmp->segment_size = vcm->cfg.segment_size;
+  len = vec_len (session->segment_name);
+  rmp->segment_name_length = clib_min (len, sizeof (rmp->segment_name));
+  clib_memcpy (rmp->segment_name, session->segment_name,
+	       rmp->segment_name_length - 1);
+  clib_memcpy (rmp->lcl_ip, session->lcl_addr.ip46.as_u8,
+	       sizeof (rmp->lcl_ip));
+  rmp->is_ip4 = session->lcl_addr.is_ip4;
+  client_q = uword_to_pointer (session->client_queue_address,
+			       unix_shared_memory_queue_t *);
+  ASSERT (client_q);
+  vl_msg_api_send_shmem (client_q, (u8 *) & rmp);
 }
 
 /*
@@ -1034,90 +1179,26 @@ send_reply:
 static void
 vl_api_connect_sock_t_handler (vl_api_connect_sock_t * mp)
 {
-  static svm_fifo_segment_create_args_t _a;
-  svm_fifo_segment_create_args_t *a = &_a;
   u32 session_index;
-  svm_fifo_segment_private_t *seg;
-  unix_shared_memory_queue_t *client_q;
-  vl_api_connect_session_reply_t *rmp;
   session_t *session = 0;
-  int rv = 0;
-  svm_fifo_t *rx_fifo;
-  svm_fifo_t *tx_fifo;
-  unix_shared_memory_queue_t *event_q = 0;
 
   clib_spinlock_lock (&vcm->sessions_lockp);
   if (!clib_fifo_free_elts (vcm->client_session_index_fifo))
     {
       if (VPPCOM_DEBUG > 1)
 	clib_warning ("[%d] client session queue is full!", getpid ());
-      rv = VNET_API_ERROR_QUEUE_FULL;
       clib_spinlock_unlock (&vcm->sessions_lockp);
-      goto send_reply;
-    }
-
-  /* Create the segment */
-  memset (a, 0, sizeof (*a));
-  a->segment_name = (char *) format ((u8 *) a->segment_name, "%d:segment%d%c",
-				     getpid (), vcm->unique_segment_index++,
-				     0);
-  a->segment_size = vcm->cfg.segment_size;
-  a->preallocated_fifo_pairs = vcm->cfg.preallocated_fifo_pairs;
-  a->rx_fifo_size = vcm->cfg.rx_fifo_size;
-  a->tx_fifo_size = vcm->cfg.tx_fifo_size;
-
-  rv = svm_fifo_segment_create (a);
-  if (PREDICT_FALSE (rv))
-    {
-      if (VPPCOM_DEBUG > 1)
-	clib_warning ("[%d] svm_fifo_segment_create ('%s') failed",
-		      getpid (), a->segment_name);
-      vec_reset_length (a->new_segment_indices);
-      rv = VNET_API_ERROR_URI_FIFO_CREATE_FAILED;
-      goto send_reply;
+      /* TBD: fix handle */
+      vppcom_send_accept_session_reply (0, VNET_API_ERROR_QUEUE_FULL);
+      return;
     }
 
-  if (VPPCOM_DEBUG > 1)
-    clib_warning ("[%d] created segment '%s'", getpid (), a->segment_name);
-
   pool_get (vcm->sessions, session);
   memset (session, 0, sizeof (*session));
   session_index = session - vcm->sessions;
 
-  session->sm_seg_index = a->new_segment_indices[0];
-  vec_reset_length (a->new_segment_indices);
-
-  seg = svm_fifo_segment_get_segment (session->sm_seg_index);
-  rx_fifo = session->server_rx_fifo =
-    svm_fifo_segment_alloc_fifo (seg, vcm->cfg.rx_fifo_size,
-				 FIFO_SEGMENT_RX_FREELIST);
-  if (PREDICT_FALSE (!session->server_rx_fifo))
-    {
-      svm_fifo_segment_delete (seg);
-      clib_warning ("[%d] rx fifo alloc failed, size %ld (0x%lx)",
-		    getpid (), vcm->cfg.rx_fifo_size, vcm->cfg.rx_fifo_size);
-      rv = VNET_API_ERROR_URI_FIFO_CREATE_FAILED;
-      clib_spinlock_unlock (&vcm->sessions_lockp);
-      goto send_reply;
-    }
-
-  tx_fifo = session->server_tx_fifo =
-    svm_fifo_segment_alloc_fifo (seg, vcm->cfg.tx_fifo_size,
-				 FIFO_SEGMENT_TX_FREELIST);
-  if (PREDICT_FALSE (!session->server_tx_fifo))
-    {
-      svm_fifo_segment_delete (seg);
-      if (VPPCOM_DEBUG > 1)
-	clib_warning ("[%d] tx fifo alloc failed, size %ld (0x%lx)",
-		      getpid (), vcm->cfg.tx_fifo_size,
-		      vcm->cfg.tx_fifo_size);
-      rv = VNET_API_ERROR_URI_FIFO_CREATE_FAILED;
-      clib_spinlock_unlock (&vcm->sessions_lockp);
-      goto send_reply;
-    }
-
-  session->server_rx_fifo->master_session_index = session_index;
-  session->server_tx_fifo->master_session_index = session_index;
+  session->client_context = mp->context;
+  session->vpp_handle = session_index;
   session->client_queue_address = mp->client_queue_address;
   session->is_cut_thru = 1;
   session->is_server = 1;
@@ -1125,51 +1206,15 @@ vl_api_connect_sock_t_handler (vl_api_connect_sock_t * mp)
   session->peer_addr.is_ip4 = mp->is_ip4;
   clib_memcpy (&session->peer_addr.ip46, mp->ip,
 	       sizeof (session->peer_addr.ip46));
-  {
-    void *oldheap;
-    ssvm_shared_header_t *sh = seg->ssvm.sh;
-
-    ssvm_lock_non_recursive (sh, 1);
-    oldheap = ssvm_push_heap (sh);
-    event_q = session->vpp_event_queue =
-      unix_shared_memory_queue_init (vcm->cfg.event_queue_size,
-				     sizeof (session_fifo_event_t),
-				     getpid (), 0 /* signal not sent */ );
-    ssvm_pop_heap (oldheap);
-    ssvm_unlock_non_recursive (sh);
-  }
 
   session->state = STATE_ACCEPT;
   clib_fifo_add1 (vcm->client_session_index_fifo, session_index);
   if (VPPCOM_DEBUG > 1)
     clib_warning
-      ("[%d] Connected cut-thru to client: sid %d, clib_fifo_elts %u!",
-       getpid (), session_index,
+      ("[%d] Got a cut-thru connect request to client: "
+       "sid %d, clib_fifo_elts %u!\n", getpid (), session_index,
        clib_fifo_elts (vcm->client_session_index_fifo));
   clib_spinlock_unlock (&vcm->sessions_lockp);
-
-send_reply:
-  rmp = vl_msg_api_alloc (sizeof (*rmp));
-  memset (rmp, 0, sizeof (*rmp));
-
-  rmp->_vl_msg_id = ntohs (VL_API_CONNECT_SESSION_REPLY);
-  rmp->context = mp->context;
-  rmp->retval = htonl (rv);
-  rmp->segment_name_length = vec_len (a->segment_name);
-  clib_memcpy (rmp->segment_name, a->segment_name, vec_len (a->segment_name));
-  vec_reset_length (a->segment_name);
-
-  if (event_q)
-    {
-      rmp->vpp_event_queue_address = pointer_to_uword (event_q);
-      rmp->server_rx_fifo = pointer_to_uword (rx_fifo);
-      rmp->server_tx_fifo = pointer_to_uword (tx_fifo);
-    }
-  client_q =
-    uword_to_pointer (mp->client_queue_address, unix_shared_memory_queue_t *);
-
-  ASSERT (client_q);
-  vl_msg_api_send_shmem (client_q, (u8 *) & rmp);
 }
 
 static void
@@ -1217,18 +1262,26 @@ vppcom_send_unbind_sock (u32 session_index)
 
   ump->_vl_msg_id = ntohs (VL_API_UNBIND_SOCK);
   ump->client_index = vcm->my_client_index;
-  ump->handle = session->vpp_session_handle;
+  ump->handle = session->vpp_handle;
   clib_spinlock_unlock (&vcm->sessions_lockp);
   vl_msg_api_send_shmem (vcm->vl_input_queue, (u8 *) & ump);
 }
 
 static int
-vppcom_session_unbind_cut_thru (session_t * session)
+vppcom_session_unbind_cut_thru (session_t * session, u32 session_index)
 {
   svm_fifo_segment_main_t *sm = &svm_fifo_segment_main;
   svm_fifo_segment_private_t *seg;
   int rv = VPPCOM_OK;
 
+  if (VPPCOM_DEBUG > 1)
+    clib_warning ("[%d] sid %d, seg_nxd %d:\n"
+		  "  server_rx_fifo %p, refcnt = %d\n"
+		  "  server_tx_fifo %p, refcnt = %d",
+		  getpid (), session_index, session->sm_seg_index,
+		  session->server_rx_fifo, session->server_rx_fifo->refcnt,
+		  session->server_tx_fifo, session->server_tx_fifo->refcnt);
+
   seg = vec_elt_at_index (sm->segments, session->sm_seg_index);
   svm_fifo_segment_free_fifo (seg, session->server_rx_fifo,
 			      FIFO_SEGMENT_RX_FREELIST);
@@ -1255,6 +1308,9 @@ vppcom_session_unbind (u32 session_index)
     }
   clib_spinlock_unlock (&vcm->sessions_lockp);
 
+  if (vcm->bind_session_index != session_index)
+    clib_warning ("[%d] ERROR: unbinding a not bound listener %u (%u)",
+		  session_index, vcm->bind_session_index);
   vcm->bind_session_index = session_index;
   vppcom_send_unbind_sock (session_index);
   rv = vppcom_wait_for_session_state_change (session_index, STATE_START,
@@ -1289,17 +1345,26 @@ vppcom_session_disconnect (u32 session_index)
 
   if (!session->is_cut_thru)
     {
+      if (VPPCOM_DEBUG > 1)
+	clib_warning ("[%d] disconnecting sid (%u)", getpid (),
+		      session_index);
       vppcom_send_disconnect (session);
       clib_spinlock_unlock (&vcm->sessions_lockp);
 
       rv = vppcom_wait_for_session_state_change (session_index,
 						 STATE_DISCONNECT, 1.0);
+      /* TBD: Force clean up on error/timeout since there is no other
+       *      way to recover from a failed disconnect.
+       */
       if ((VPPCOM_DEBUG > 0) && (rv < 0))
 	clib_warning ("[%d] disconnect (session %d) failed, rv = %s (%d)",
 		      getpid (), session_index, vppcom_retval_str (rv), rv);
     }
   else
-    clib_spinlock_unlock (&vcm->sessions_lockp);
+    {
+      /* TBD: Handle cut-thru disconnect */
+      clib_spinlock_unlock (&vcm->sessions_lockp);
+    }
 
   return VPPCOM_OK;
 }
@@ -1461,7 +1526,7 @@ defaulted:
 
   vcl_mem = mmap (0, vcl_cfg->heapsize, PROT_READ | PROT_WRITE,
 		  MAP_SHARED | MAP_ANONYMOUS, -1, 0);
-  if (vcl_mem <= 0)
+  if (vcl_mem == MAP_FAILED)
     {
       clib_unix_error ("[%d] ERROR: mmap(0, %lld == 0x%llx, "
 		       "PROT_READ | PROT_WRITE,MAP_SHARED | MAP_ANONYMOUS, "
@@ -2082,7 +2147,7 @@ vppcom_session_close (uint32_t session_index)
 
       if (is_cut_thru && is_server && (state == STATE_ACCEPT))
 	{
-	  rv = vppcom_session_unbind_cut_thru (session);
+	  rv = vppcom_session_unbind_cut_thru (session, session_index);
 	  if ((VPPCOM_DEBUG > 0) && (rv < 0))
 	    clib_warning ("[%d] unbind cut-thru (session %d) failed, "
 			  "rv = %s (%d)",
@@ -2225,13 +2290,14 @@ vppcom_session_listen (uint32_t listen_session_index, uint32_t q_len)
 
 int
 vppcom_session_accept (uint32_t listen_session_index, vppcom_endpt_t * ep,
-		       double wait_for_time)
+		       uint32_t flags, double wait_for_time)
 {
   session_t *listen_session = 0;
   session_t *client_session = 0;
-  u32 client_session_index;
+  u32 client_session_index = ~0;
   int rv;
   f64 wait_for;
+  char *cut_thru_str;
 
   clib_spinlock_lock (&vcm->sessions_lockp);
   rv = vppcom_session_at_index (listen_session_index, &listen_session);
@@ -2295,13 +2361,11 @@ vppcom_session_accept (uint32_t listen_session_index, vppcom_endpt_t * ep,
   ASSERT (client_session->peer_addr.is_ip4 ==
 	  listen_session->lcl_addr.is_ip4);
 
+  client_session->is_nonblocking = (flags & O_NONBLOCK) ? 1 : 0;
   if (VPPCOM_DEBUG > 0)
-    clib_warning ("[%d] Got a request: client sid %d", getpid (),
-		  client_session_index);
-
-  // Copy the lcl information from the listening session to the client session
-  //  client_session->lcl_port = listen_session->lcl_port;
-  //  client_session->lcl_addr = listen_session->lcl_addr;
+    clib_warning ("[%d] Got a request: client sid %d, flags %d, "
+		  " is_nonblocking %u", getpid (), client_session_index,
+		  flags, client_session->is_nonblocking);
 
   ep->vrf = client_session->vrf;
   ep->is_cut_thru = client_session->is_cut_thru;
@@ -2313,12 +2377,115 @@ vppcom_session_accept (uint32_t listen_session_index, vppcom_endpt_t * ep,
   else
     clib_memcpy (ep->ip, &client_session->peer_addr.ip46.ip6,
 		 sizeof (ip6_address_t));
+
+  if (client_session->is_server && client_session->is_cut_thru)
+    {
+      static svm_fifo_segment_create_args_t _a;
+      svm_fifo_segment_create_args_t *a = &_a;
+      svm_fifo_segment_private_t *seg;
+
+      cut_thru_str = "cut-thru ";
+
+      /* Create the segment */
+      memset (a, 0, sizeof (*a));
+      a->segment_name = (char *)
+	format ((u8 *) a->segment_name, "%d:segment%d%c",
+		getpid (), vcm->unique_segment_index++, 0);
+      a->segment_size = vcm->cfg.segment_size;
+      a->preallocated_fifo_pairs = vcm->cfg.preallocated_fifo_pairs;
+      a->rx_fifo_size = vcm->cfg.rx_fifo_size;
+      a->tx_fifo_size = vcm->cfg.tx_fifo_size;
+
+      rv = svm_fifo_segment_create (a);
+      if (PREDICT_FALSE (rv))
+	{
+	  if (VPPCOM_DEBUG > 1)
+	    clib_warning ("[%d] svm_fifo_segment_create ('%s') failed",
+			  getpid (), a->segment_name);
+	  vec_reset_length (a->new_segment_indices);
+	  rv = VNET_API_ERROR_URI_FIFO_CREATE_FAILED;
+	  vppcom_send_connect_session_reply (client_session, rv);
+	  clib_spinlock_unlock (&vcm->sessions_lockp);
+	  return VPPCOM_ENOMEM;
+	}
+
+      client_session->segment_name = vec_dup ((u8 *) a->segment_name);
+      client_session->sm_seg_index = a->new_segment_indices[0];
+      vec_free (a->new_segment_indices);
+
+      seg = svm_fifo_segment_get_segment (client_session->sm_seg_index);
+      client_session->server_rx_fifo =
+	svm_fifo_segment_alloc_fifo (seg, vcm->cfg.rx_fifo_size,
+				     FIFO_SEGMENT_RX_FREELIST);
+      if (PREDICT_FALSE (!client_session->server_rx_fifo))
+	{
+	  svm_fifo_segment_delete (seg);
+	  clib_warning ("[%d] rx fifo alloc failed, size %ld (0x%lx)",
+			getpid (), vcm->cfg.rx_fifo_size,
+			vcm->cfg.rx_fifo_size);
+	  rv = VNET_API_ERROR_URI_FIFO_CREATE_FAILED;
+	  vppcom_send_connect_session_reply (client_session, rv);
+	  clib_spinlock_unlock (&vcm->sessions_lockp);
+	  return VPPCOM_ENOMEM;
+	}
+      client_session->server_rx_fifo->master_session_index =
+	client_session_index;
+
+      client_session->server_tx_fifo =
+	svm_fifo_segment_alloc_fifo (seg, vcm->cfg.tx_fifo_size,
+				     FIFO_SEGMENT_TX_FREELIST);
+      if (PREDICT_FALSE (!client_session->server_tx_fifo))
+	{
+	  svm_fifo_segment_delete (seg);
+	  if (VPPCOM_DEBUG > 1)
+	    clib_warning ("[%d] tx fifo alloc failed, size %ld (0x%lx)",
+			  getpid (), vcm->cfg.tx_fifo_size,
+			  vcm->cfg.tx_fifo_size);
+	  rv = VNET_API_ERROR_URI_FIFO_CREATE_FAILED;
+	  vppcom_send_connect_session_reply (client_session, rv);
+	  clib_spinlock_unlock (&vcm->sessions_lockp);
+	  return VPPCOM_ENOMEM;
+	}
+      client_session->server_tx_fifo->master_session_index =
+	client_session_index;
+
+      if (VPPCOM_DEBUG > 1)
+	clib_warning ("[%d] created segment '%s': rx_fifo %p, tx_fifo %p",
+		      getpid (), client_session->segment_name,
+		      client_session->server_rx_fifo,
+		      client_session->server_tx_fifo);
+
+#ifdef CUT_THRU_EVENT_QUEUE	/* TBD */
+      {
+	void *oldheap;
+	ssvm_shared_header_t *sh = seg->ssvm.sh;
+
+	ssvm_lock_non_recursive (sh, 1);
+	oldheap = ssvm_push_heap (sh);
+	event_q = client_session->vpp_event_queue =
+	  unix_shared_memory_queue_init (vcm->cfg.event_queue_size,
+					 sizeof (session_fifo_event_t),
+					 getpid (), 0 /* signal not sent */ );
+	ssvm_pop_heap (oldheap);
+	ssvm_unlock_non_recursive (sh);
+      }
+#endif
+      vppcom_send_connect_session_reply (client_session, 0);
+    }
+  else
+    {
+      cut_thru_str = " ";
+      vppcom_send_accept_session_reply (client_session->vpp_handle, 0);
+    }
+
   if (VPPCOM_DEBUG > 0)
-    clib_warning ("[%d] sid %d, accepted peer address %U peer port %u",
-		  getpid (), client_session_index, format_ip46_address,
-		  &client_session->peer_addr.ip46,
+    clib_warning ("[%d] sid %d, accepted %sconnection to peer address "
+		  "%U peer port %u",
+		  getpid (), client_session_index, cut_thru_str,
+		  format_ip46_address, &client_session->peer_addr.ip46,
 		  client_session->peer_addr.is_ip4,
 		  clib_net_to_host_u16 (client_session->peer_port));
+
   clib_spinlock_unlock (&vcm->sessions_lockp);
   return (int) client_session_index;
 }
@@ -2438,7 +2605,8 @@ vppcom_session_read_internal (uint32_t session_index, void *buf, int n,
 	     session->server_rx_fifo : session->server_tx_fifo);
   fifo_str = ((!session->is_cut_thru || session->is_server) ?
 	      "server_rx_fifo" : "server_tx_fifo");
-  poll_et = EPOLLET & session->vep.ev.events;
+  poll_et =
+    ((EPOLLET | EPOLLIN) & session->vep.ev.events) == (EPOLLET | EPOLLIN);
   clib_spinlock_unlock (&vcm->sessions_lockp);
 
   do
@@ -2481,6 +2649,7 @@ vppcom_session_read_ready (session_t * session, u32 session_index)
 {
   svm_fifo_t *rx_fifo = 0;
   int ready = 0;
+  u32 poll_et;
 
   /* Assumes caller has acquired spinlock: vcm->sessions_lockp */
   if (session->is_vep)
@@ -2510,14 +2679,25 @@ vppcom_session_read_ready (session_t * session, u32 session_index)
       ready = svm_fifo_max_dequeue (rx_fifo);
     }
 
-  if (VPPCOM_DEBUG > 3)
-    clib_warning ("[%d] sid %d, is_listen %u, peek %s (%p), ready = %d",
+  poll_et =
+    ((EPOLLET | EPOLLIN) & session->vep.ev.events) == (EPOLLET | EPOLLIN);
+  if (poll_et && (ready == 0))
+    {
+      if (VPPCOM_DEBUG > 11)
+	clib_warning ("[%d] sid %d: current vep.et_mask = 0x%x", getpid (),
+		      session_index, session->vep.et_mask);
+      session->vep.et_mask |= EPOLLIN;
+      if (VPPCOM_DEBUG > 11)
+	clib_warning ("[%d] sid %d: updated vep.et_mask = 0x%x", getpid (),
+		      session_index, session->vep.et_mask);
+    }
+
+  if (session->vep.et_mask && (VPPCOM_DEBUG > 11))
+    clib_warning ("[%d] sid %d, is_listen %u, peek %s (%p), ready = %d, "
+		  "et_mask 0x%x",
 		  getpid (), session_index, session->is_listen,
 		  session->is_server ? "server_rx_fifo" : "server_tx_fifo",
-		  rx_fifo, ready);
-  if ((session->vep.ev.events & EPOLLET) && (ready == 0))
-    session->vep.et_mask |= EPOLLIN;
-
+		  rx_fifo, ready, session->vep.et_mask);
   return ready;
 }
 
@@ -2568,7 +2748,8 @@ vppcom_session_write (uint32_t session_index, void *buf, int n)
   fifo_str = ((!session->is_cut_thru || session->is_server) ?
 	      "server_tx_fifo" : "server_rx_fifo");
   q = session->vpp_event_queue;
-  poll_et = EPOLLET & session->vep.ev.events;
+  poll_et = (((EPOLLET | EPOLLOUT) & session->vep.ev.events) ==
+	     (EPOLLET | EPOLLOUT));
   clib_spinlock_unlock (&vcm->sessions_lockp);
 
   do
@@ -2624,6 +2805,7 @@ vppcom_session_write_ready (session_t * session, u32 session_index)
   svm_fifo_t *tx_fifo;
   char *fifo_str;
   int ready;
+  u32 poll_et;
 
   /* Assumes caller has acquired spinlock: vcm->sessions_lockp */
   if (session->is_vep)
@@ -2653,7 +2835,9 @@ vppcom_session_write_ready (session_t * session, u32 session_index)
   if (VPPCOM_DEBUG > 3)
     clib_warning ("[%d] sid %d, peek %s (%p), ready = %d", getpid (),
 		  session_index, fifo_str, tx_fifo, ready);
-  if ((session->vep.ev.events & EPOLLET) && (ready == 0))
+  poll_et = (((EPOLLET | EPOLLOUT) & session->vep.ev.events) ==
+	     (EPOLLET | EPOLLOUT));
+  if (poll_et && (ready == 0))
     session->vep.et_mask |= EPOLLOUT;
 
   return ready;
@@ -3108,22 +3292,6 @@ done:
   return rv;
 }
 
-#define VCL_LOCK_AND_GET_SESSION(I, S)                  \
-do {                                                    \
-  clib_spinlock_lock (&vcm->sessions_lockp);            \
-  rv = vppcom_session_at_index (I, S);                  \
-  if (PREDICT_FALSE (rv))                               \
-    {                                                   \
-      clib_spinlock_unlock (&vcm->sessions_lockp);      \
-                                                        \
-      if (VPPCOM_DEBUG > 0)                             \
-        clib_warning ("[%s] ERROR: Invalid ##I (%u)!",  \
-                      getpid (), I);                  \
-                                                        \
-      goto done;                                        \
-    }                                                   \
-} while (0)
-
 int
 vppcom_epoll_wait (uint32_t vep_idx, struct epoll_event *events,
 		   int maxevents, double wait_for_time)
@@ -3218,16 +3386,17 @@ vppcom_epoll_wait (uint32_t vep_idx, struct epoll_event *events,
 
 	  add_event = clear_et_mask = 0;
 
-	  if ((EPOLLIN & session_events) && (EPOLLIN & et_mask))
+	  if (EPOLLIN & session_events)
 	    {
 	      VCL_LOCK_AND_GET_SESSION (sid, &session);
 	      ready = vppcom_session_read_ready (session, sid);
 	      clib_spinlock_unlock (&vcm->sessions_lockp);
-	      if (ready > 0)
+	      if ((ready > 0) && (EPOLLIN & et_mask))
 		{
 		  add_event = 1;
 		  events[num_ev].events |= EPOLLIN;
-		  if (EPOLLET & session_events)
+		  if (((EPOLLET | EPOLLIN) & session_events) ==
+		      (EPOLLET | EPOLLIN))
 		    clear_et_mask |= EPOLLIN;
 		}
 	      else if (ready < 0)
@@ -3246,16 +3415,17 @@ vppcom_epoll_wait (uint32_t vep_idx, struct epoll_event *events,
 		}
 	    }
 
-	  if ((EPOLLOUT & session_events) && (EPOLLOUT & et_mask))
+	  if (EPOLLOUT & session_events)
 	    {
 	      VCL_LOCK_AND_GET_SESSION (sid, &session);
 	      ready = vppcom_session_write_ready (session, sid);
 	      clib_spinlock_unlock (&vcm->sessions_lockp);
-	      if (ready > 0)
+	      if ((ready > 0) && (EPOLLOUT & et_mask))
 		{
 		  add_event = 1;
 		  events[num_ev].events |= EPOLLOUT;
-		  if (EPOLLET & session_events)
+		  if (((EPOLLET | EPOLLOUT) & session_events) ==
+		      (EPOLLET | EPOLLOUT))
 		    clear_et_mask |= EPOLLOUT;
 		}
 	      else if (ready < 0)
@@ -3329,14 +3499,18 @@ vppcom_session_attr (uint32_t session_index, uint32_t op,
     {
     case VPPCOM_ATTR_GET_NREAD:
       rv = vppcom_session_read_ready (session, session_index);
-      if (VPPCOM_DEBUG > 1)
-	clib_warning ("[%d] VPPCOM_ATTR_GET_NREAD: nread = %d",
+      if (VPPCOM_DEBUG > 2)
+	clib_warning ("[%d] VPPCOM_ATTR_GET_NREAD: sid %u, nread = %d",
 		      getpid (), rv);
 
       break;
 
-    case VPPCOM_ATTR_PEEK_NREAD:
-      /* TBD */
+    case VPPCOM_ATTR_GET_NWRITE:
+      rv = vppcom_session_write_ready (session, session_index);
+      if (VPPCOM_DEBUG > 2)
+	clib_warning ("[%d] VPPCOM_ATTR_GET_NWRITE: sid %u, nwrite = %d",
+		      getpid (), session_index, rv);
+
       break;
 
     case VPPCOM_ATTR_GET_FLAGS:
@@ -3344,10 +3518,10 @@ vppcom_session_attr (uint32_t session_index, uint32_t op,
 	{
 	  *flags = O_RDWR | ((session->is_nonblocking) ? O_NONBLOCK : 0);
 	  *buflen = sizeof (*flags);
-	  if (VPPCOM_DEBUG > 1)
-	    clib_warning ("[%d] VPPCOM_ATTR_GET_FLAGS: flags = 0x%08x, "
-			  "is_nonblocking = %u", getpid (), *flags,
-			  session->is_nonblocking);
+	  if (VPPCOM_DEBUG > 2)
+	    clib_warning ("[%d] VPPCOM_ATTR_GET_FLAGS: sid %u, "
+			  "flags = 0x%08x, is_nonblocking = %u", getpid (),
+			  session_index, *flags, session->is_nonblocking);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -3357,10 +3531,10 @@ vppcom_session_attr (uint32_t session_index, uint32_t op,
       if (buffer && buflen && (*buflen >= sizeof (*flags)))
 	{
 	  session->is_nonblocking = (*flags & O_NONBLOCK) ? 1 : 0;
-	  if (VPPCOM_DEBUG > 1)
-	    clib_warning ("[%d] VPPCOM_ATTR_SET_FLAGS: flags = 0x%08x, "
-			  "is_nonblocking = %u", getpid (), *flags,
-			  session->is_nonblocking);
+	  if (VPPCOM_DEBUG > 2)
+	    clib_warning ("[%d] VPPCOM_ATTR_SET_FLAGS: sid %u, "
+			  "flags = 0x%08x, is_nonblocking = %u",
+			  getpid (), *flags, session->is_nonblocking);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -3380,7 +3554,7 @@ vppcom_session_attr (uint32_t session_index, uint32_t op,
 			 sizeof (ip6_address_t));
 	  *buflen = sizeof (*ep);
 	  if (VPPCOM_DEBUG > 1)
-	    clib_warning ("[%d] VPPCOM_ATTR_GET_PEER_ADDR: sid %u is_ip4 = "
+	    clib_warning ("[%d] VPPCOM_ATTR_GET_PEER_ADDR: sid %u, is_ip4 = "
 			  "%u, addr = %U, port %u", getpid (),
 			  session_index, ep->is_ip4, format_ip46_address,
 			  &session->peer_addr.ip46, ep->is_ip4,
@@ -3404,7 +3578,7 @@ vppcom_session_attr (uint32_t session_index, uint32_t op,
 			 sizeof (ip6_address_t));
 	  *buflen = sizeof (*ep);
 	  if (VPPCOM_DEBUG > 1)
-	    clib_warning ("[%d] VPPCOM_ATTR_GET_LCL_ADDR: sid %u is_ip4 = "
+	    clib_warning ("[%d] VPPCOM_ATTR_GET_LCL_ADDR: sid %u, is_ip4 = "
 			  "%u, addr = %U port %d", getpid (),
 			  session_index, ep->is_ip4, format_ip46_address,
 			  &session->lcl_addr.ip46, ep->is_ip4,