vapi: support api clients within vpp process

Add vapi_connect_from_vpp() and vapi_disconnect_from_vpp()
calls to allow API clients from within VPP process.

Add a new memclnt_create version that gives the user a
knob to enable or disable dead client scans (keepalive).

Type: feature
Signed-off-by: Ole Troan <ot@cisco.com>
Change-Id: Id0b7bb89308db3a3aed2d3fcbedf4e1282dcd03f
Signed-off-by: Ole Troan <ot@cisco.com>

2 files changed, 103 insertions, 2 deletions

diff --git a/src/vlibmemory/memclnt.api b/src/vlibmemory/memclnt.api
index bd999b51dd0..0532f1734bf 100644
--- a/src/vlibmemory/memclnt.api
+++ b/src/vlibmemory/memclnt.api
@@ -232,3 +232,19 @@ define control_ping_reply
   u32 vpe_pid;
 };
 
+define memclnt_create_v2 {
+    u32 context;                /* opaque value to be returned in the reply */
+    i32 ctx_quota;              /* requested punt context quota */
+    u64 input_queue;            /* client's queue */
+    string name[64];            /* for show, find by name, whatever */
+    u32 api_versions[8];        /* client-server pairs use as desired */
+    bool keepalive[default=true];  /* dead client scan keepalives */
+};
+
+define memclnt_create_v2_reply {
+    u32 context;                /* opaque value from the create request */
+    i32 response;               /* Non-negative = success */
+    u64 handle;                 /* handle by which vlib knows this client */
+    u32 index;                  /* index, used e.g. by API trace replay */
+    u64 message_table;          /* serialized message table in shmem */
+};
diff --git a/src/vlibmemory/memory_api.c b/src/vlibmemory/memory_api.c
index a16110f2fa1..b1d250b8a5f 100644
--- a/src/vlibmemory/memory_api.c
+++ b/src/vlibmemory/memory_api.c
@@ -192,6 +192,7 @@ vl_api_memclnt_create_t_handler (vl_api_memclnt_create_t * mp)
 
   regp->name = format (0, "%s", mp->name);
   vec_add1 (regp->name, 0);
+  regp->keepalive = true;
 
   if (am->serialized_message_table_in_shmem == 0)
     am->serialized_message_table_in_shmem =
@@ -218,6 +219,87 @@ vl_api_memclnt_create_t_handler (vl_api_memclnt_create_t * mp)
 }
 
 void
+vl_api_memclnt_create_v2_t_handler (vl_api_memclnt_create_v2_t *mp)
+{
+  vl_api_registration_t **regpp;
+  vl_api_registration_t *regp;
+  vl_api_memclnt_create_v2_reply_t *rp;
+  svm_queue_t *q;
+  int rv = 0;
+  void *oldheap;
+  api_main_t *am = vlibapi_get_main ();
+  u8 *msg_table;
+
+  /*
+   * This is tortured. Maintain a vlib-address-space private
+   * pool of client registrations. We use the shared-memory virtual
+   * address of client structure as a handle, to allow direct
+   * manipulation of context quota vbls from the client library.
+   *
+   * This scheme causes trouble w/ API message trace replay, since
+   * some random VA from clib_mem_alloc() certainly won't
+   * occur in the Linux sim. The (very) few places
+   * that care need to use the pool index.
+   *
+   * Putting the registration object(s) into a pool in shared memory and
+   * using the pool index as a handle seems like a great idea.
+   * Unfortunately, each and every reference to that pool would need
+   * to be protected by a mutex:
+   *
+   *     Client                      VLIB
+   *     ------                      ----
+   *     convert pool index to
+   *     pointer.
+   *     <deschedule>
+   *                                 expand pool
+   *                                 <deschedule>
+   *     kaboom!
+   */
+
+  pool_get (am->vl_clients, regpp);
+
+  oldheap = vl_msg_push_heap ();
+  *regpp = clib_mem_alloc (sizeof (vl_api_registration_t));
+
+  regp = *regpp;
+  clib_memset (regp, 0, sizeof (*regp));
+  regp->registration_type = REGISTRATION_TYPE_SHMEM;
+  regp->vl_api_registration_pool_index = regpp - am->vl_clients;
+  regp->vlib_rp = am->vlib_rp;
+  regp->shmem_hdr = am->shmem_hdr;
+  regp->clib_file_index = am->shmem_hdr->clib_file_index;
+
+  q = regp->vl_input_queue = (svm_queue_t *) (uword) mp->input_queue;
+  VL_MSG_API_SVM_QUEUE_UNPOISON (q);
+
+  regp->name = format (0, "%s", mp->name);
+  vec_add1 (regp->name, 0);
+  regp->keepalive = mp->keepalive;
+
+  if (am->serialized_message_table_in_shmem == 0)
+    am->serialized_message_table_in_shmem =
+      vl_api_serialize_message_table (am, 0);
+
+  if (am->vlib_rp != am->vlib_primary_rp)
+    msg_table = vl_api_serialize_message_table (am, 0);
+  else
+    msg_table = am->serialized_message_table_in_shmem;
+
+  vl_msg_pop_heap (oldheap);
+
+  rp = vl_msg_api_alloc (sizeof (*rp));
+  rp->_vl_msg_id = ntohs (VL_API_MEMCLNT_CREATE_V2_REPLY);
+  rp->handle = (uword) regp;
+  rp->index = vl_msg_api_handle_from_index_and_epoch (
+    regp->vl_api_registration_pool_index, am->shmem_hdr->application_restarts);
+  rp->context = mp->context;
+  rp->response = ntohl (rv);
+  rp->message_table = pointer_to_uword (msg_table);
+
+  vl_msg_api_send_shmem (q, (u8 *) &rp);
+}
+
+void
 vl_api_call_reaper_functions (u32 client_index)
 {
   clib_error_t *error = 0;
@@ -399,6 +481,7 @@ vl_api_memclnt_keepalive_t_handler (vl_api_memclnt_keepalive_t * mp)
 
 #define foreach_vlib_api_msg                                                  \
   _ (MEMCLNT_CREATE, memclnt_create, 0)                                       \
+  _ (MEMCLNT_CREATE_V2, memclnt_create_v2, 0)                                 \
   _ (MEMCLNT_DELETE, memclnt_delete, 0)                                       \
   _ (MEMCLNT_KEEPALIVE, memclnt_keepalive, 0)                                 \
   _ (MEMCLNT_KEEPALIVE_REPLY, memclnt_keepalive_reply, 0)
@@ -578,8 +661,10 @@ vl_mem_api_dead_client_scan (api_main_t * am, vl_shmem_hdr_t * shm, f64 now)
 
   /* *INDENT-OFF* */
   pool_foreach (regpp, am->vl_clients)  {
+      if (!(*regpp)->keepalive)
+	continue;
       vl_mem_send_client_keepalive_w_reg (am, now, regpp, &dead_indices,
-                                          &confused_indices);
+					  &confused_indices);
   }
   /* *INDENT-ON* */
 
@@ -944,7 +1029,7 @@ vl_api_client_index_to_input_queue (u32 index)
 static clib_error_t *
 setup_memclnt_exit (vlib_main_t * vm)
 {
-  atexit (vl_unmap_shmem);
+  atexit (vl_unmap_shmem_client);
   return 0;
 }