api: keep api common code in vlibapi

Type: refactor
Change-Id: I6edbff9a02fcb3c592ccfe8f47ddb3f848be1b6d
Signed-off-by: Damjan Marion <damarion@cisco.com>

3 files changed, 975 insertions, 9 deletions

diff --git a/src/vlibapi/CMakeLists.txt b/src/vlibapi/CMakeLists.txt
index e6937a6db01..95bb4cf7469 100644
--- a/src/vlibapi/CMakeLists.txt
+++ b/src/vlibapi/CMakeLists.txt
@@ -11,16 +11,18 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-install(
-  FILES
-  api_helper_macros.h
+add_vpp_library (vlibapi
+  SOURCES
+  api_shared.c
+  node_serialize.c
+  memory_shared.c
+
+  INSTALL_HEADERS
   api.h
-  vat_helper_macros.h
   api_common.h
+  api_helper_macros.h
   api_types.h
-
-  DESTINATION
-  ${CMAKE_INSTALL_INCLUDEDIR}/vlibapi
-
-  COMPONENT vpp-dev
+  vat_helper_macros.h
+  memory_shared.h
 )
+
diff --git a/src/vlibapi/memory_shared.c b/src/vlibapi/memory_shared.c
new file mode 100644
index 00000000000..77a610b9434
--- /dev/null
+++ b/src/vlibapi/memory_shared.c
@@ -0,0 +1,817 @@
+/*
+ *------------------------------------------------------------------
+ * memclnt_shared.c - API message handling, common code for both clients
+ * and the vlib process itself.
+ *
+ *
+ * Copyright (c) 2009 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *------------------------------------------------------------------
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <unistd.h>
+#include <signal.h>
+
+#include <vppinfra/format.h>
+#include <vppinfra/byte_order.h>
+#include <vppinfra/error.h>
+#include <vppinfra/elog.h>
+#include <svm/queue.h>
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vlibmemory/memory_api.h>
+#include <vlibmemory/vl_memory_msg_enum.h>
+#include <vlibapi/api_common.h>
+
+#define vl_typedefs
+#include <vlibmemory/vl_memory_api_h.h>
+#undef vl_typedefs
+
+#define DEBUG_MESSAGE_BUFFER_OVERRUN 0
+
+__clib_nosanitize_addr static inline void *
+vl_msg_api_alloc_internal (svm_region_t *vlib_rp, int nbytes, int pool,
+			   int may_return_null)
+{
+  int i;
+  msgbuf_t *rv;
+  ring_alloc_t *ap;
+  svm_queue_t *q;
+  void *oldheap;
+  vl_shmem_hdr_t *shmem_hdr;
+  api_main_t *am = vlibapi_get_main ();
+
+  shmem_hdr = (void *) vlib_rp->user_ctx;
+
+#if DEBUG_MESSAGE_BUFFER_OVERRUN > 0
+  nbytes += 4;
+#endif
+
+  ASSERT (pool == 0 || vlib_get_thread_index () == 0);
+
+  if (shmem_hdr == 0)
+    {
+      clib_warning ("shared memory header NULL");
+      return 0;
+    }
+
+  /* account for the msgbuf_t header */
+  nbytes += sizeof (msgbuf_t);
+
+  if (shmem_hdr->vl_rings == 0)
+    {
+      clib_warning ("vl_rings NULL");
+      ASSERT (0);
+      abort ();
+    }
+
+  if (shmem_hdr->client_rings == 0)
+    {
+      clib_warning ("client_rings NULL");
+      ASSERT (0);
+      abort ();
+    }
+
+  ap = pool ? shmem_hdr->vl_rings : shmem_hdr->client_rings;
+  for (i = 0; i < vec_len (ap); i++)
+    {
+      /* Too big? */
+      if (nbytes > ap[i].size)
+	{
+	  continue;
+	}
+
+      q = ap[i].rp;
+      if (pool == 0)
+	{
+	  pthread_mutex_lock (&q->mutex);
+	}
+      rv = (msgbuf_t *) (&q->data[0] + q->head * q->elsize);
+      /*
+       * Is this item still in use?
+       */
+      if (rv->q)
+	{
+	  u32 now = (u32) time (0);
+
+	  if (PREDICT_TRUE (rv->gc_mark_timestamp == 0))
+	    rv->gc_mark_timestamp = now;
+	  else
+	    {
+	      if (now - rv->gc_mark_timestamp > 10)
+		{
+		  if (CLIB_DEBUG > 0)
+		    {
+		      u16 *msg_idp, msg_id;
+		      vl_api_msg_data_t *m;
+		      clib_warning
+			("garbage collect pool %d ring %d index %d", pool, i,
+			 q->head);
+		      msg_idp = (u16 *) (rv->data);
+		      msg_id = clib_net_to_host_u16 (*msg_idp);
+		      m = vl_api_get_msg_data (am, msg_id);
+		      if (m)
+			clib_warning ("msg id %d name %s", (u32) msg_id,
+				      m->name);
+		    }
+		  shmem_hdr->garbage_collects++;
+		  goto collected;
+		}
+	    }
+
+
+	  /* yes, loser; try next larger pool */
+	  ap[i].misses++;
+	  if (pool == 0)
+	    pthread_mutex_unlock (&q->mutex);
+	  continue;
+	}
+    collected:
+
+      /* OK, we have a winner */
+      ap[i].hits++;
+      /*
+       * Remember the source queue, although we
+       * don't need to know the queue to free the item.
+       */
+      rv->q = q;
+      rv->gc_mark_timestamp = 0;
+      q->head++;
+      if (q->head == q->maxsize)
+	q->head = 0;
+
+      if (pool == 0)
+	pthread_mutex_unlock (&q->mutex);
+      goto out;
+    }
+
+  /*
+   * Request too big, or head element of all size-compatible rings
+   * still in use. Fall back to shared-memory malloc.
+   */
+  am->ring_misses++;
+
+  oldheap = vl_msg_push_heap_w_region (vlib_rp);
+  if (may_return_null)
+    {
+      rv = clib_mem_alloc_or_null (nbytes);
+      if (PREDICT_FALSE (rv == 0))
+	{
+	  vl_msg_pop_heap_w_region (vlib_rp, oldheap);
+	  return 0;
+	}
+    }
+  else
+    rv = clib_mem_alloc (nbytes);
+
+  rv->q = 0;
+  rv->gc_mark_timestamp = 0;
+  vl_msg_pop_heap_w_region (vlib_rp, oldheap);
+
+out:
+#if DEBUG_MESSAGE_BUFFER_OVERRUN > 0
+  {
+    nbytes -= 4;
+    u32 *overrun;
+    overrun = (u32 *) (rv->data + nbytes - sizeof (msgbuf_t));
+    *overrun = 0x1badbabe;
+  }
+#endif
+  rv->data_len = htonl (nbytes - sizeof (msgbuf_t));
+
+  VL_MSG_API_UNPOISON (rv->data);
+  return (rv->data);
+}
+
+void *
+vl_msg_api_alloc (int nbytes)
+{
+  int pool;
+  api_main_t *am = vlibapi_get_main ();
+  vl_shmem_hdr_t *shmem_hdr = am->shmem_hdr;
+
+  /*
+   * Clients use pool-0, vlib proc uses pool 1
+   */
+  pool = (am->our_pid == shmem_hdr->vl_pid);
+  return vl_msg_api_alloc_internal (am->vlib_rp, nbytes, pool,
+				    0 /* may_return_null */ );
+}
+
+void *
+vl_msg_api_alloc_zero (int nbytes)
+{
+  void *ret;
+
+  ret = vl_msg_api_alloc (nbytes);
+  clib_memset (ret, 0, nbytes);
+  return ret;
+}
+
+void *
+vl_msg_api_alloc_or_null (int nbytes)
+{
+  int pool;
+  api_main_t *am = vlibapi_get_main ();
+  vl_shmem_hdr_t *shmem_hdr = am->shmem_hdr;
+
+  pool = (am->our_pid == shmem_hdr->vl_pid);
+  return vl_msg_api_alloc_internal (am->vlib_rp, nbytes, pool,
+				    1 /* may_return_null */ );
+}
+
+void *
+vl_msg_api_alloc_as_if_client (int nbytes)
+{
+  api_main_t *am = vlibapi_get_main ();
+  return vl_msg_api_alloc_internal (am->vlib_rp, nbytes, 0,
+				    0 /* may_return_null */ );
+}
+
+void *
+vl_msg_api_alloc_zero_as_if_client (int nbytes)
+{
+  void *ret;
+
+  ret = vl_msg_api_alloc_as_if_client (nbytes);
+  clib_memset (ret, 0, nbytes);
+  return ret;
+}
+
+void *
+vl_msg_api_alloc_as_if_client_or_null (int nbytes)
+{
+  api_main_t *am = vlibapi_get_main ();
+  return vl_msg_api_alloc_internal (am->vlib_rp, nbytes, 0,
+				    1 /* may_return_null */ );
+}
+
+void *
+vl_mem_api_alloc_as_if_client_w_reg (vl_api_registration_t * reg, int nbytes)
+{
+  return vl_msg_api_alloc_internal (reg->vlib_rp, nbytes, 0,
+				    0 /* may_return_null */ );
+}
+
+void
+vl_msg_api_free_w_region (svm_region_t * vlib_rp, void *a)
+{
+  msgbuf_t *rv;
+  void *oldheap;
+
+  rv = (msgbuf_t *) (((u8 *) a) - offsetof (msgbuf_t, data));
+
+  /*
+   * Here's the beauty of the scheme.  Only one proc/thread has
+   * control of a given message buffer. To free a buffer, we just clear the
+   * queue field, and leave. No locks, no hits, no errors...
+   */
+  if (rv->q)
+    {
+      rv->q = 0;
+      rv->gc_mark_timestamp = 0;
+#if DEBUG_MESSAGE_BUFFER_OVERRUN > 0
+      {
+	u32 *overrun;
+	overrun = (u32 *) (rv->data + ntohl (rv->data_len));
+	ASSERT (*overrun == 0x1badbabe);
+      }
+#endif
+      VL_MSG_API_POISON (rv->data);
+      return;
+    }
+
+  oldheap = vl_msg_push_heap_w_region (vlib_rp);
+
+#if DEBUG_MESSAGE_BUFFER_OVERRUN > 0
+  {
+    u32 *overrun;
+    overrun = (u32 *) (rv->data + ntohl (rv->data_len));
+    ASSERT (*overrun == 0x1badbabe);
+  }
+#endif
+
+  clib_mem_free (rv);
+  vl_msg_pop_heap_w_region (vlib_rp, oldheap);
+}
+
+void
+vl_msg_api_free (void *a)
+{
+  api_main_t *am = vlibapi_get_main ();
+  vl_msg_api_free_w_region (am->vlib_rp, a);
+}
+
+static void
+vl_msg_api_free_nolock (void *a)
+{
+  msgbuf_t *rv;
+  void *oldheap;
+  api_main_t *am = vlibapi_get_main ();
+
+  rv = (msgbuf_t *) (((u8 *) a) - offsetof (msgbuf_t, data));
+  /*
+   * Here's the beauty of the scheme.  Only one proc/thread has
+   * control of a given message buffer. To free a buffer, we just clear the
+   * queue field, and leave. No locks, no hits, no errors...
+   */
+  if (rv->q)
+    {
+      rv->q = 0;
+      VL_MSG_API_POISON (rv->data);
+      return;
+    }
+
+  oldheap = svm_push_data_heap (am->vlib_rp);
+  clib_mem_free (rv);
+  svm_pop_heap (oldheap);
+}
+
+void
+vl_set_memory_root_path (const char *name)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  am->root_path = name;
+}
+
+void
+vl_set_memory_uid (int uid)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  am->api_uid = uid;
+}
+
+void
+vl_set_memory_gid (int gid)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  am->api_gid = gid;
+}
+
+void
+vl_set_global_memory_baseva (u64 baseva)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  am->global_baseva = baseva;
+}
+
+void
+vl_set_global_memory_size (u64 size)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  am->global_size = size;
+}
+
+void
+vl_set_api_memory_size (u64 size)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  am->api_size = size;
+}
+
+void
+vl_set_global_pvt_heap_size (u64 size)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  am->global_pvt_heap_size = size;
+}
+
+void
+vl_set_api_pvt_heap_size (u64 size)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  am->api_pvt_heap_size = size;
+}
+
+static void
+vl_api_default_mem_config (vl_shmem_hdr_t * shmem_hdr)
+{
+  api_main_t *am = vlibapi_get_main ();
+  u32 vlib_input_queue_length;
+
+  /* vlib main input queue */
+  vlib_input_queue_length = 1024;
+  if (am->vlib_input_queue_length)
+    vlib_input_queue_length = am->vlib_input_queue_length;
+
+  shmem_hdr->vl_input_queue =
+    svm_queue_alloc_and_init (vlib_input_queue_length, sizeof (uword),
+			      getpid ());
+
+#define _(sz,n)                                                 \
+    do {                                                        \
+        ring_alloc_t _rp;                                       \
+        _rp.rp = svm_queue_alloc_and_init ((n), (sz), 0); 	\
+        _rp.size = (sz);                                        \
+        _rp.nitems = n;                                         \
+        _rp.hits = 0;                                           \
+        _rp.misses = 0;                                         \
+        vec_add1(shmem_hdr->vl_rings, _rp);                     \
+    } while (0);
+
+  foreach_vl_aring_size;
+#undef _
+
+#define _(sz,n)                                                 \
+    do {                                                        \
+        ring_alloc_t _rp;                                       \
+        _rp.rp = svm_queue_alloc_and_init ((n), (sz), 0); 	\
+        _rp.size = (sz);                                        \
+        _rp.nitems = n;                                         \
+        _rp.hits = 0;                                           \
+        _rp.misses = 0;                                         \
+        vec_add1(shmem_hdr->client_rings, _rp);                 \
+    } while (0);
+
+  foreach_clnt_aring_size;
+#undef _
+}
+
+void
+vl_api_mem_config (vl_shmem_hdr_t * hdr, vl_api_shm_elem_config_t * config)
+{
+  vl_api_shm_elem_config_t *c;
+  ring_alloc_t *rp;
+  u32 size;
+
+  if (!config)
+    {
+      vl_api_default_mem_config (hdr);
+      return;
+    }
+
+  vec_foreach (c, config)
+  {
+    switch (c->type)
+      {
+      case VL_API_QUEUE:
+	hdr->vl_input_queue = svm_queue_alloc_and_init (c->count, c->size,
+							getpid ());
+	continue;
+      case VL_API_VLIB_RING:
+	vec_add2 (hdr->vl_rings, rp, 1);
+	break;
+      case VL_API_CLIENT_RING:
+	vec_add2 (hdr->client_rings, rp, 1);
+	break;
+      default:
+	clib_warning ("unknown config type: %d", c->type);
+	continue;
+      }
+
+    size = sizeof (ring_alloc_t) + c->size;
+    rp->rp = svm_queue_alloc_and_init (c->count, size, 0);
+    rp->size = size;
+    rp->nitems = c->count;
+    rp->hits = 0;
+    rp->misses = 0;
+  }
+}
+
+void
+vl_init_shmem (svm_region_t * vlib_rp, vl_api_shm_elem_config_t * config,
+	       int is_vlib, int is_private_region)
+{
+  api_main_t *am = vlibapi_get_main ();
+  vl_shmem_hdr_t *shmem_hdr = 0;
+  void *oldheap;
+  ASSERT (vlib_rp);
+
+  /* $$$$ need private region config parameters */
+
+  oldheap = svm_push_data_heap (vlib_rp);
+
+  vec_validate (shmem_hdr, 0);
+  shmem_hdr->version = VL_SHM_VERSION;
+  shmem_hdr->clib_file_index = VL_API_INVALID_FI;
+
+  /* Set up the queue and msg ring allocator */
+  vl_api_mem_config (shmem_hdr, config);
+
+  if (is_private_region == 0)
+    {
+      am->shmem_hdr = shmem_hdr;
+      am->vlib_rp = vlib_rp;
+      am->our_pid = getpid ();
+      if (is_vlib)
+	am->shmem_hdr->vl_pid = am->our_pid;
+    }
+  else
+    shmem_hdr->vl_pid = am->our_pid;
+
+  svm_pop_heap (oldheap);
+
+  /*
+   * After absolutely everything that a client might see is set up,
+   * declare the shmem region valid
+   */
+  vlib_rp->user_ctx = shmem_hdr;
+
+  pthread_mutex_unlock (&vlib_rp->mutex);
+}
+
+int
+vl_map_shmem (const char *region_name, int is_vlib)
+{
+  svm_map_region_args_t _a, *a = &_a;
+  svm_region_t *vlib_rp, *root_rp;
+  api_main_t *am = vlibapi_get_main ();
+  int i;
+  struct timespec ts, tsrem;
+  char *vpe_api_region_suffix = "-vpe-api";
+
+  clib_memset (a, 0, sizeof (*a));
+
+  if (strstr (region_name, vpe_api_region_suffix))
+    {
+      u8 *root_path = format (0, "%s", region_name);
+      vec_set_len (root_path,
+		   vec_len (root_path) - strlen (vpe_api_region_suffix));
+      vec_terminate_c_string (root_path);
+      a->root_path = (const char *) root_path;
+      am->root_path = (const char *) root_path;
+    }
+
+  if (is_vlib == 0)
+    {
+      int tfd;
+      u8 *api_name;
+      /*
+       * Clients wait for vpp to set up the root / API regioins
+       */
+      if (am->root_path)
+	api_name = format (0, "/dev/shm/%s-%s%c", am->root_path,
+			   region_name + 1, 0);
+      else
+	api_name = format (0, "/dev/shm%s%c", region_name, 0);
+
+      /* Wait up to 100 seconds... */
+      for (i = 0; i < 10000; i++)
+	{
+	  ts.tv_sec = 0;
+	  ts.tv_nsec = 10000 * 1000;	/* 10 ms */
+	  while (nanosleep (&ts, &tsrem) < 0)
+	    ts = tsrem;
+	  tfd = open ((char *) api_name, O_RDWR);
+	  if (tfd >= 0)
+	    break;
+	}
+      vec_free (api_name);
+      if (tfd < 0)
+	{
+	  clib_warning ("region init fail");
+	  return -2;
+	}
+      close (tfd);
+      svm_region_init_chroot_uid_gid (am->root_path, getuid (), getgid ());
+    }
+
+  if (a->root_path != NULL)
+    {
+      a->name = "/vpe-api";
+    }
+  else
+    a->name = region_name;
+  a->size = am->api_size ? am->api_size : (16 << 20);
+  a->flags = SVM_FLAGS_MHEAP;
+  a->uid = am->api_uid;
+  a->gid = am->api_gid;
+  a->pvt_heap_size = am->api_pvt_heap_size;
+
+  vlib_rp = svm_region_find_or_create (a);
+
+  if (vlib_rp == 0)
+    return (-2);
+
+  pthread_mutex_lock (&vlib_rp->mutex);
+  /* Has someone else set up the shared-memory variable table? */
+  if (vlib_rp->user_ctx)
+    {
+      am->shmem_hdr = (void *) vlib_rp->user_ctx;
+      am->our_pid = getpid ();
+      if (is_vlib)
+	{
+	  svm_queue_t *q;
+	  uword old_msg;
+	  /*
+	   * application restart. Reset cached pids, API message
+	   * rings, list of clients; otherwise, various things
+	   * fail. (e.g. queue non-empty notification)
+	   */
+
+	  /* ghosts keep the region from disappearing properly */
+	  svm_client_scan_this_region_nolock (vlib_rp);
+	  am->shmem_hdr->application_restarts++;
+	  q = am->shmem_hdr->vl_input_queue;
+	  am->shmem_hdr->vl_pid = getpid ();
+	  q->consumer_pid = am->shmem_hdr->vl_pid;
+	  /* Drain the input queue, freeing msgs */
+	  for (i = 0; i < 10; i++)
+	    {
+	      if (pthread_mutex_trylock (&q->mutex) == 0)
+		{
+		  pthread_mutex_unlock (&q->mutex);
+		  goto mutex_ok;
+		}
+	      ts.tv_sec = 0;
+	      ts.tv_nsec = 10000 * 1000;	/* 10 ms */
+	      while (nanosleep (&ts, &tsrem) < 0)
+		ts = tsrem;
+	    }
+	  /* Mutex buggered, "fix" it */
+	  clib_memset (&q->mutex, 0, sizeof (q->mutex));
+	  clib_warning ("forcibly release main input queue mutex");
+
+	mutex_ok:
+	  am->vlib_rp = vlib_rp;
+	  while (svm_queue_sub (q, (u8 *) & old_msg, SVM_Q_NOWAIT, 0)
+		 != -2 /* queue underflow */ )
+	    {
+	      vl_msg_api_free_nolock ((void *) old_msg);
+	      am->shmem_hdr->restart_reclaims++;
+	    }
+	  pthread_mutex_unlock (&vlib_rp->mutex);
+	  root_rp = svm_get_root_rp ();
+	  ASSERT (root_rp);
+	  /* Clean up the root region client list */
+	  pthread_mutex_lock (&root_rp->mutex);
+	  svm_client_scan_this_region_nolock (root_rp);
+	  pthread_mutex_unlock (&root_rp->mutex);
+	}
+      else
+	{
+	  pthread_mutex_unlock (&vlib_rp->mutex);
+	}
+      am->vlib_rp = vlib_rp;
+      vec_add1 (am->mapped_shmem_regions, vlib_rp);
+      return 0;
+    }
+  /* Clients simply have to wait... */
+  if (!is_vlib)
+    {
+      pthread_mutex_unlock (&vlib_rp->mutex);
+
+      /* Wait up to 100 seconds... */
+      for (i = 0; i < 10000; i++)
+	{
+	  ts.tv_sec = 0;
+	  ts.tv_nsec = 10000 * 1000;	/* 10 ms */
+	  while (nanosleep (&ts, &tsrem) < 0)
+	    ts = tsrem;
+	  if (vlib_rp->user_ctx)
+	    goto ready;
+	}
+      /* Clean up and leave... */
+      svm_region_unmap (vlib_rp);
+      clib_warning ("region init fail");
+      return (-2);
+
+    ready:
+      am->shmem_hdr = (void *) vlib_rp->user_ctx;
+      am->our_pid = getpid ();
+      am->vlib_rp = vlib_rp;
+      vec_add1 (am->mapped_shmem_regions, vlib_rp);
+      return 0;
+    }
+
+  /* Nope, it's our problem... */
+  vl_init_shmem (vlib_rp, 0 /* default config */ , 1 /* is vlib */ ,
+		 0 /* is_private_region */ );
+
+  vec_add1 (am->mapped_shmem_regions, vlib_rp);
+  return 0;
+}
+
+void
+vl_register_mapped_shmem_region (svm_region_t * rp)
+{
+  api_main_t *am = vlibapi_get_main ();
+
+  vec_add1 (am->mapped_shmem_regions, rp);
+}
+
+static void
+vl_unmap_shmem_internal (u8 is_client)
+{
+  svm_region_t *rp;
+  int i;
+  api_main_t *am = vlibapi_get_main ();
+
+  if (!svm_get_root_rp ())
+    return;
+
+  for (i = 0; i < vec_len (am->mapped_shmem_regions); i++)
+    {
+      rp = am->mapped_shmem_regions[i];
+      is_client ? svm_region_unmap_client (rp) : svm_region_unmap (rp);
+    }
+
+  vec_free (am->mapped_shmem_regions);
+  am->shmem_hdr = 0;
+
+  is_client ? svm_region_exit_client () : svm_region_exit ();
+
+  vec_free (am->msg_data);
+}
+
+void
+vl_unmap_shmem (void)
+{
+  vl_unmap_shmem_internal (0);
+}
+
+void
+vl_unmap_shmem_client (void)
+{
+  vl_unmap_shmem_internal (1);
+}
+
+void
+vl_msg_api_send_shmem (svm_queue_t * q, u8 * elem)
+{
+  api_main_t *am = vlibapi_get_main ();
+  void *msg = (void *) *(uword *) elem;
+
+  if (am->tx_trace && am->tx_trace->enabled)
+    vl_msg_api_trace (am, am->tx_trace, msg);
+
+  /*
+   * Announce a probable binary API client bug:
+   * some client's input queue is stuffed.
+   * The situation may be recoverable, or not.
+   */
+  if (PREDICT_FALSE
+      (am->vl_clients /* vpp side */  && (q->cursize == q->maxsize)))
+    {
+      if (PREDICT_FALSE (am->elog_trace_api_messages))
+	{
+          /* *INDENT-OFF* */
+          ELOG_TYPE_DECLARE (e) =
+            {
+              .format = "api-client-queue-stuffed: %x%x",
+              .format_args = "i4i4",
+            };
+          /* *INDENT-ON* */
+	  struct
+	  {
+	    u32 hi, low;
+	  } *ed;
+	  ed = ELOG_DATA (am->elog_main, e);
+	  ed->hi = (uword) q >> 32;
+	  ed->low = (uword) q & 0xFFFFFFFF;
+	  clib_warning ("WARNING: client input queue at %llx is stuffed...",
+			q);
+	}
+    }
+  VL_MSG_API_POISON (msg);
+  (void) svm_queue_add (q, elem, 0 /* nowait */ );
+}
+
+int
+vl_mem_api_can_send (svm_queue_t * q)
+{
+  return (q->cursize < q->maxsize);
+}
+
+void
+vl_msg_api_send_shmem_nolock (svm_queue_t * q, u8 * elem)
+{
+  api_main_t *am = vlibapi_get_main ();
+  void *msg = (void *) *(uword *) elem;
+
+  if (am->tx_trace && am->tx_trace->enabled)
+    vl_msg_api_trace (am, am->tx_trace, msg);
+
+  (void) svm_queue_add_nolock (q, elem);
+  VL_MSG_API_POISON (msg);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vlibapi/memory_shared.h b/src/vlibapi/memory_shared.h
new file mode 100644
index 00000000000..4c4773d060b
--- /dev/null
+++ b/src/vlibapi/memory_shared.h
@@ -0,0 +1,147 @@
+/*
+ *------------------------------------------------------------------
+ * Copyright (c) 2018 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *------------------------------------------------------------------
+ */
+
+#ifndef SRC_VLIBMEMORY_MEMORY_SHARED_H_
+#define SRC_VLIBMEMORY_MEMORY_SHARED_H_
+
+#include <vlibapi/api_common.h>
+#include <vppinfra/error.h>
+
+/* Allocated in shared memory */
+
+/*
+ * Ring-allocation scheme for client API messages
+ *
+ * Only one proc/thread has control of a given message buffer.
+ * To free a buffer allocated from one of these rings, we clear
+ * a field in the buffer (header), and leave.
+ *
+ * No locks, no hits, no errors...
+ */
+typedef struct ring_alloc_
+{
+  svm_queue_t *rp;
+  u16 size;
+  u16 nitems;
+  u32 hits;
+  u32 misses;
+} ring_alloc_t;
+
+typedef enum
+{
+  VL_API_VLIB_RING,
+  VL_API_CLIENT_RING,
+  VL_API_QUEUE
+} vl_api_shm_config_type_t;
+
+typedef struct vl_api_shm_elem_config_
+{
+  u8 type;
+  u8 _pad;
+  u16 count;
+  u32 size;
+} vl_api_shm_elem_config_t;
+
+STATIC_ASSERT (sizeof (vl_api_shm_elem_config_t) == 8,
+	       "Size must be exactly 8 bytes");
+
+/*
+ * Initializers for the (shared-memory) rings
+ * _(size, n). Note: each msg has space for a header.
+ */
+#define foreach_vl_aring_size                   \
+_(64+sizeof(ring_alloc_t), 1024)                \
+_(256+sizeof(ring_alloc_t), 128)                \
+_(1024+sizeof(ring_alloc_t), 64)
+
+#define foreach_clnt_aring_size                 \
+ _(1024+sizeof(ring_alloc_t), 1024)             \
+ _(2048+sizeof(ring_alloc_t), 128)              \
+ _(4096+sizeof(ring_alloc_t), 8)
+
+typedef struct vl_shmem_hdr_
+{
+  int version;
+
+  /* getpid () for the VLIB client process */
+  volatile int vl_pid;
+
+  /* Client sends VLIB msgs here. */
+  svm_queue_t *vl_input_queue;
+
+  /* Vector of rings; one for each size. */
+
+  /* VLIB allocates buffers to send msgs to clients here. */
+  ring_alloc_t *vl_rings;
+
+  /* Clients allocate buffer to send msgs to VLIB here. */
+  ring_alloc_t *client_rings;
+
+  /* Number of detected application restarts */
+  u32 application_restarts;
+
+  /* Number of messages reclaimed during application restart */
+  u32 restart_reclaims;
+
+  /* Number of garbage-collected messages */
+  u32 garbage_collects;
+
+  /* Socket file index used to bootstrap shmem region */
+  u32 clib_file_index;
+} vl_shmem_hdr_t;
+
+#define VL_SHM_VERSION 2
+#define VL_API_EPOCH_MASK 0xFF
+#define VL_API_EPOCH_SHIFT 8
+
+void *vl_msg_api_alloc (int nbytes);
+void *vl_msg_api_alloc_zero (int nbytes);
+void *vl_msg_api_alloc_or_null (int nbytes);
+void *vl_msg_api_alloc_as_if_client (int nbytes);
+void *vl_msg_api_alloc_zero_as_if_client (int nbytes);
+void *vl_msg_api_alloc_as_if_client_or_null (int nbytes);
+void *vl_mem_api_alloc_as_if_client_w_reg (vl_api_registration_t * reg,
+					   int nbytes);
+void vl_msg_api_free (void *a);
+void vl_msg_api_free_w_region (svm_region_t * vlib_rp, void *a);
+int vl_map_shmem (const char *region_name, int is_vlib);
+void vl_unmap_shmem (void);
+void vl_unmap_shmem_client (void);
+void vl_register_mapped_shmem_region (svm_region_t * rp);
+void vl_msg_api_send_shmem (svm_queue_t * q, u8 * elem);
+int vl_mem_api_can_send (svm_queue_t * q);
+void vl_set_memory_region_name (const char *name);
+void vl_set_memory_root_path (const char *root_path);
+void vl_set_memory_uid (int uid);
+void vl_set_memory_gid (int gid);
+void vl_set_global_memory_baseva (u64 baseva);
+void vl_set_global_memory_size (u64 size);
+void vl_set_api_memory_size (u64 size);
+void vl_set_global_pvt_heap_size (u64 size);
+void vl_set_api_pvt_heap_size (u64 size);
+void vl_init_shmem (svm_region_t * vlib_rp, vl_api_shm_elem_config_t * config,
+		    int is_vlib, int is_private_region);
+
+#endif /* SRC_VLIBMEMORY_MEMORY_SHARED_H_ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */