76 files changed, 679 insertions, 201 deletions

diff --git a/src/core/ext/census/gen/trace_context.pb.h b/src/core/ext/census/gen/trace_context.pb.h
index ea127bf70a..6fafc04c81 100644
--- a/src/core/ext/census/gen/trace_context.pb.h
+++ b/src/core/ext/census/gen/trace_context.pb.h
@@ -90,4 +90,4 @@ extern const pb_field_t google_trace_TraceContext_fields[5];
 #endif
 /* @@protoc_insertion_point(eof) */
 
-#endif
+#endif /* GRPC_CORE_EXT_CENSUS_GEN_TRACE_CONTEXT_PB_H */
diff --git a/src/core/ext/census/trace_label.h b/src/core/ext/census/trace_label.h
index 0e4a8d885f..701f6f5a63 100644
--- a/src/core/ext/census/trace_label.h
+++ b/src/core/ext/census/trace_label.h
@@ -58,4 +58,4 @@ typedef struct trace_label {
   } value;
 } trace_label;
 
-#endif
+#endif /* GRPC_CORE_EXT_CENSUS_TRACE_LABEL_H */
diff --git a/src/core/ext/census/trace_propagation.h b/src/core/ext/census/trace_propagation.h
index 75c4ebaa39..0c27bfa111 100644
--- a/src/core/ext/census/trace_propagation.h
+++ b/src/core/ext/census/trace_propagation.h
@@ -60,4 +60,4 @@ size_t trace_span_context_to_http_format(const trace_span_context *ctxt,
 size_t http_format_to_trace_span_context(const char *buf, size_t buf_size,
                                          trace_span_context *ctxt);
 
-#endif
+#endif /* GRPC_CORE_EXT_CENSUS_TRACE_PROPAGATION_H */
diff --git a/src/core/ext/census/trace_status.h b/src/core/ext/census/trace_status.h
index adc0ebd0c0..0734ec6d3d 100644
--- a/src/core/ext/census/trace_status.h
+++ b/src/core/ext/census/trace_status.h
@@ -42,4 +42,4 @@ typedef struct trace_status {
   trace_string errorMessage;
 } trace_status;
 
-#endif
+#endif /* GRPC_CORE_EXT_CENSUS_TRACE_STATUS_H */
diff --git a/src/core/ext/census/trace_string.h b/src/core/ext/census/trace_string.h
index 8e77ee9f7e..cd63cfb92f 100644
--- a/src/core/ext/census/trace_string.h
+++ b/src/core/ext/census/trace_string.h
@@ -47,4 +47,4 @@ typedef struct trace_string {
   size_t length;
 } trace_string;
 
-#endif
+#endif /* GRPC_CORE_EXT_CENSUS_TRACE_STRING_H */
diff --git a/src/core/ext/census/tracing.h b/src/core/ext/census/tracing.h
index c2b947ae40..3a7c6f45e4 100644
--- a/src/core/ext/census/tracing.h
+++ b/src/core/ext/census/tracing.h
@@ -121,4 +121,4 @@ free to ignore all further calls using the Span. EndSpanOptions can
 optionally be NULL. */
 void trace_end_span(const trace_status *status, trace_span_context *span_ctxt);
 
-#endif
+#endif /* GRPC_CORE_EXT_CENSUS_TRACING_H */
diff --git a/src/core/ext/client_channel/README.md b/src/core/ext/filters/client_channel/README.md
index 7c209db12e..7c209db12e 100644
--- a/src/core/ext/client_channel/README.md
+++ b/src/core/ext/filters/client_channel/README.md
diff --git a/src/core/ext/client_channel/channel_connectivity.c b/src/core/ext/filters/client_channel/channel_connectivity.c
index f6cb3b9115..62f58fb278 100644
--- a/src/core/ext/client_channel/channel_connectivity.c
+++ b/src/core/ext/filters/client_channel/channel_connectivity.c
@@ -36,7 +36,7 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/surface/completion_queue.h"
diff --git a/src/core/ext/client_channel/client_channel.c b/src/core/ext/filters/client_channel/client_channel.c
index 435a3ab0fe..d289272489 100644
--- a/src/core/ext/client_channel/client_channel.c
+++ b/src/core/ext/filters/client_channel/client_channel.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
 
 #include <stdbool.h>
 #include <stdio.h>
@@ -43,12 +43,12 @@
 #include <grpc/support/sync.h>
 #include <grpc/support/useful.h>
 
-#include "src/core/ext/client_channel/http_connect_handshaker.h"
-#include "src/core/ext/client_channel/lb_policy_registry.h"
-#include "src/core/ext/client_channel/proxy_mapper_registry.h"
-#include "src/core/ext/client_channel/resolver_registry.h"
-#include "src/core/ext/client_channel/retry_throttle.h"
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/http_connect_handshaker.h"
+#include "src/core/ext/filters/client_channel/lb_policy_registry.h"
+#include "src/core/ext/filters/client_channel/proxy_mapper_registry.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/ext/filters/client_channel/retry_throttle.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
 #include "src/core/lib/channel/deadline_filter.h"
@@ -374,8 +374,7 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
     // resolver actually specified.
     channel_arg =
         grpc_channel_args_find(chand->resolver_result, GRPC_ARG_LB_ADDRESSES);
-    if (channel_arg != NULL) {
-      GPR_ASSERT(channel_arg->type == GRPC_ARG_POINTER);
+    if (channel_arg != NULL && channel_arg->type == GRPC_ARG_POINTER) {
       grpc_lb_addresses *addresses = channel_arg->value.pointer.p;
       bool found_backend_address = false;
       for (size_t i = 0; i < addresses->num_addresses; ++i) {
@@ -643,14 +642,26 @@ static grpc_error *cc_init_channel_elem(grpc_exec_ctx *exec_ctx,
   // Record client channel factory.
   const grpc_arg *arg = grpc_channel_args_find(args->channel_args,
                                                GRPC_ARG_CLIENT_CHANNEL_FACTORY);
-  GPR_ASSERT(arg != NULL);
-  GPR_ASSERT(arg->type == GRPC_ARG_POINTER);
+  if (arg == NULL) {
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Missing client channel factory in args for client channel filter");
+  }
+  if (arg->type != GRPC_ARG_POINTER) {
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "client channel factory arg must be a pointer");
+  }
   grpc_client_channel_factory_ref(arg->value.pointer.p);
   chand->client_channel_factory = arg->value.pointer.p;
   // Get server name to resolve, using proxy mapper if needed.
   arg = grpc_channel_args_find(args->channel_args, GRPC_ARG_SERVER_URI);
-  GPR_ASSERT(arg != NULL);
-  GPR_ASSERT(arg->type == GRPC_ARG_STRING);
+  if (arg == NULL) {
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Missing server uri in args for client channel filter");
+  }
+  if (arg->type != GRPC_ARG_STRING) {
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "server uri arg must be a string");
+  }
   char *proxy_name = NULL;
   grpc_channel_args *new_args = NULL;
   grpc_proxy_mappers_map_name(exec_ctx, arg->value.string, args->channel_args,
diff --git a/src/core/ext/client_channel/client_channel.h b/src/core/ext/filters/client_channel/client_channel.h
index 5e6e64e58b..8d2490ea55 100644
--- a/src/core/ext/client_channel/client_channel.h
+++ b/src/core/ext/filters/client_channel/client_channel.h
@@ -31,11 +31,11 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_CLIENT_CHANNEL_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_CLIENT_CHANNEL_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_H
 
-#include "src/core/ext/client_channel/client_channel_factory.h"
-#include "src/core/ext/client_channel/resolver.h"
+#include "src/core/ext/filters/client_channel/client_channel_factory.h"
+#include "src/core/ext/filters/client_channel/resolver.h"
 #include "src/core/lib/channel/channel_stack.h"
 
 // Channel arg key for server URI string.
@@ -61,4 +61,4 @@ void grpc_client_channel_watch_connectivity_state(
 grpc_subchannel_call *grpc_client_channel_get_subchannel_call(
     grpc_call_element *elem);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_CLIENT_CHANNEL_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_H */
diff --git a/src/core/ext/client_channel/client_channel_factory.c b/src/core/ext/filters/client_channel/client_channel_factory.c
index d2707a1556..44e83b54b5 100644
--- a/src/core/ext/client_channel/client_channel_factory.c
+++ b/src/core/ext/filters/client_channel/client_channel_factory.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/client_channel_factory.h"
+#include "src/core/ext/filters/client_channel/client_channel_factory.h"
 
 void grpc_client_channel_factory_ref(grpc_client_channel_factory* factory) {
   factory->vtable->ref(factory);
diff --git a/src/core/ext/client_channel/client_channel_factory.h b/src/core/ext/filters/client_channel/client_channel_factory.h
index bf2764b537..2355588f18 100644
--- a/src/core/ext/client_channel/client_channel_factory.h
+++ b/src/core/ext/filters/client_channel/client_channel_factory.h
@@ -31,12 +31,12 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_CLIENT_CHANNEL_FACTORY_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_CLIENT_CHANNEL_FACTORY_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_FACTORY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_FACTORY_H
 
 #include <grpc/impl/codegen/grpc_types.h>
 
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 #include "src/core/lib/channel/channel_stack.h"
 
 // Channel arg key for client channel factory.
@@ -89,4 +89,4 @@ grpc_channel *grpc_client_channel_factory_create_channel(
 grpc_arg grpc_client_channel_factory_create_channel_arg(
     grpc_client_channel_factory *factory);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_CLIENT_CHANNEL_FACTORY_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_FACTORY_H */
diff --git a/src/core/ext/client_channel/client_channel_plugin.c b/src/core/ext/filters/client_channel/client_channel_plugin.c
index f51277d0b2..944af01af4 100644
--- a/src/core/ext/client_channel/client_channel_plugin.c
+++ b/src/core/ext/filters/client_channel/client_channel_plugin.c
@@ -37,14 +37,14 @@
 
 #include <grpc/support/alloc.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/client_channel/http_connect_handshaker.h"
-#include "src/core/ext/client_channel/http_proxy.h"
-#include "src/core/ext/client_channel/lb_policy_registry.h"
-#include "src/core/ext/client_channel/proxy_mapper_registry.h"
-#include "src/core/ext/client_channel/resolver_registry.h"
-#include "src/core/ext/client_channel/retry_throttle.h"
-#include "src/core/ext/client_channel/subchannel_index.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/http_connect_handshaker.h"
+#include "src/core/ext/filters/client_channel/http_proxy.h"
+#include "src/core/ext/filters/client_channel/lb_policy_registry.h"
+#include "src/core/ext/filters/client_channel/proxy_mapper_registry.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/ext/filters/client_channel/retry_throttle.h"
+#include "src/core/ext/filters/client_channel/subchannel_index.h"
 #include "src/core/lib/surface/channel_init.h"
 
 static bool append_filter(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/ext/client_channel/connector.c b/src/core/ext/filters/client_channel/connector.c
index 7a720fd1bd..51c1d7ece7 100644
--- a/src/core/ext/client_channel/connector.c
+++ b/src/core/ext/filters/client_channel/connector.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/connector.h"
+#include "src/core/ext/filters/client_channel/connector.h"
 
 grpc_connector* grpc_connector_ref(grpc_connector* connector) {
   connector->vtable->ref(connector);
diff --git a/src/core/ext/client_channel/connector.h b/src/core/ext/filters/client_channel/connector.h
index 94b5fb5c9e..23040c3e23 100644
--- a/src/core/ext/client_channel/connector.h
+++ b/src/core/ext/filters/client_channel/connector.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_CONNECTOR_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_CONNECTOR_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CONNECTOR_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CONNECTOR_H
 
 #include "src/core/lib/channel/channel_stack.h"
 #include "src/core/lib/iomgr/resolve_address.h"
@@ -85,4 +85,4 @@ void grpc_connector_connect(grpc_exec_ctx *exec_ctx, grpc_connector *connector,
 void grpc_connector_shutdown(grpc_exec_ctx *exec_ctx, grpc_connector *connector,
                              grpc_error *why);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_CONNECTOR_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CONNECTOR_H */
diff --git a/src/core/ext/client_channel/http_connect_handshaker.c b/src/core/ext/filters/client_channel/http_connect_handshaker.c
index 778d76c39f..c09a863d00 100644
--- a/src/core/ext/client_channel/http_connect_handshaker.c
+++ b/src/core/ext/filters/client_channel/http_connect_handshaker.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/http_connect_handshaker.h"
+#include "src/core/ext/filters/client_channel/http_connect_handshaker.h"
 
 #include <string.h>
 
@@ -40,9 +40,9 @@
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/client_channel/resolver_registry.h"
-#include "src/core/ext/client_channel/uri_parser.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/handshaker_registry.h"
 #include "src/core/lib/http/format_request.h"
diff --git a/src/core/ext/client_channel/http_connect_handshaker.h b/src/core/ext/filters/client_channel/http_connect_handshaker.h
index 3059d551e3..6d7c204d71 100644
--- a/src/core/ext/client_channel/http_connect_handshaker.h
+++ b/src/core/ext/filters/client_channel/http_connect_handshaker.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H
 
 /// Channel arg indicating the server in HTTP CONNECT request (string).
 /// The presence of this arg triggers the use of HTTP CONNECT.
@@ -46,4 +46,4 @@
 /// Registers handshaker factory.
 void grpc_http_connect_register_handshaker_factory();
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H */
diff --git a/src/core/ext/client_channel/http_proxy.c b/src/core/ext/filters/client_channel/http_proxy.c
index e280cef101..f8a2d06b8a 100644
--- a/src/core/ext/client_channel/http_proxy.c
+++ b/src/core/ext/filters/client_channel/http_proxy.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/http_proxy.h"
+#include "src/core/ext/filters/client_channel/http_proxy.h"
 
 #include <stdbool.h>
 #include <string.h>
@@ -40,9 +40,9 @@
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/http_connect_handshaker.h"
-#include "src/core/ext/client_channel/proxy_mapper_registry.h"
-#include "src/core/ext/client_channel/uri_parser.h"
+#include "src/core/ext/filters/client_channel/http_connect_handshaker.h"
+#include "src/core/ext/filters/client_channel/proxy_mapper_registry.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/support/env.h"
 
diff --git a/src/core/ext/client_channel/http_proxy.h b/src/core/ext/filters/client_channel/http_proxy.h
index c8882b1ef1..f0df74bbda 100644
--- a/src/core/ext/client_channel/http_proxy.h
+++ b/src/core/ext/filters/client_channel/http_proxy.h
@@ -31,9 +31,9 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_HTTP_PROXY_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_HTTP_PROXY_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_PROXY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_PROXY_H
 
 void grpc_register_http_proxy_mapper();
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_HTTP_PROXY_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_PROXY_H */
diff --git a/src/core/ext/client_channel/lb_policy.c b/src/core/ext/filters/client_channel/lb_policy.c
index aba51add53..2d31499d13 100644
--- a/src/core/ext/client_channel/lb_policy.c
+++ b/src/core/ext/filters/client_channel/lb_policy.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/lb_policy.h"
+#include "src/core/ext/filters/client_channel/lb_policy.h"
 #include "src/core/lib/iomgr/combiner.h"
 
 #define WEAK_REF_BITS 16
diff --git a/src/core/ext/client_channel/lb_policy.h b/src/core/ext/filters/client_channel/lb_policy.h
index 3405709c2c..25427666ae 100644
--- a/src/core/ext/client_channel/lb_policy.h
+++ b/src/core/ext/filters/client_channel/lb_policy.h
@@ -31,10 +31,10 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_H
 
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 #include "src/core/lib/iomgr/polling_entity.h"
 #include "src/core/lib/transport/connectivity_state.h"
 
@@ -206,4 +206,4 @@ grpc_connectivity_state grpc_lb_policy_check_connectivity_locked(
     grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
     grpc_error **connectivity_error);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_H */
diff --git a/src/core/ext/lb_policy/grpclb/grpclb.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
index 601b0e643b..ff8d319309 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
@@ -106,14 +106,14 @@
 #include <grpc/support/string_util.h>
 #include <grpc/support/time.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/client_channel/client_channel_factory.h"
-#include "src/core/ext/client_channel/lb_policy_factory.h"
-#include "src/core/ext/client_channel/lb_policy_registry.h"
-#include "src/core/ext/client_channel/parse_address.h"
-#include "src/core/ext/lb_policy/grpclb/grpclb.h"
-#include "src/core/ext/lb_policy/grpclb/grpclb_channel.h"
-#include "src/core/ext/lb_policy/grpclb/load_balancer_api.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/client_channel_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h"
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy_registry.h"
+#include "src/core/ext/filters/client_channel/parse_address.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/sockaddr.h"
@@ -847,7 +847,9 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
    * this is the right LB policy to use. */
   const grpc_arg *arg =
       grpc_channel_args_find(args->args, GRPC_ARG_LB_ADDRESSES);
-  GPR_ASSERT(arg != NULL && arg->type == GRPC_ARG_POINTER);
+  if (arg == NULL || arg->type != GRPC_ARG_POINTER) {
+    return NULL;
+  }
   grpc_lb_addresses *addresses = arg->value.pointer.p;
   size_t num_grpclb_addrs = 0;
   for (size_t i = 0; i < addresses->num_addresses; ++i) {
diff --git a/src/core/ext/lb_policy/grpclb/grpclb.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
index ff23f3a545..b069fae2f8 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
@@ -31,14 +31,14 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_LB_POLICY_GRPCLB_GRPCLB_H
-#define GRPC_CORE_EXT_LB_POLICY_GRPCLB_GRPCLB_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_H
 
-#include "src/core/ext/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 
 /** Returns a load balancing factory for the glb policy, which tries to connect
  * to a load balancing server to decide the next successfully connected
  * subchannel to pick. */
 grpc_lb_policy_factory *grpc_glb_lb_factory_create();
 
-#endif /* GRPC_CORE_EXT_LB_POLICY_GRPCLB_GRPCLB_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_H */
diff --git a/src/core/ext/lb_policy/grpclb/grpclb_channel.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
index 1b8bbab1b6..d6201f2387 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb_channel.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
@@ -34,8 +34,8 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/lb_policy/grpclb/grpclb_channel.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/support/string.h"
diff --git a/src/core/ext/lb_policy/grpclb/grpclb_channel.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
index f66082d78e..9730c971d9 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb_channel.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
@@ -31,10 +31,10 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H
-#define GRPC_CORE_EXT_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H
 
-#include "src/core/ext/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 #include "src/core/lib/slice/slice_hash_table.h"
 
 /** Create the channel used for communicating with an LB service.
@@ -53,4 +53,5 @@ grpc_channel_args *get_lb_channel_args(grpc_exec_ctx *exec_ctx,
                                        grpc_slice_hash_table *targets_info,
                                        const grpc_channel_args *args);
 
-#endif /* GRPC_CORE_EXT_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H \
+          */
diff --git a/src/core/ext/lb_policy/grpclb/grpclb_channel_secure.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c
index 2fee5f1b8e..a145cba63c 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb_channel_secure.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c
@@ -34,8 +34,8 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/lb_policy/grpclb/grpclb_channel.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/security/credentials/credentials.h"
diff --git a/src/core/ext/lb_policy/grpclb/load_balancer_api.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
index 3c4604c402..10af252531 100644
--- a/src/core/ext/lb_policy/grpclb/load_balancer_api.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/lb_policy/grpclb/load_balancer_api.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h"
 #include "third_party/nanopb/pb_decode.h"
 #include "third_party/nanopb/pb_encode.h"
 
diff --git a/src/core/ext/lb_policy/grpclb/load_balancer_api.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
index b4c967e426..d014b8800c 100644
--- a/src/core/ext/lb_policy/grpclb/load_balancer_api.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
@@ -31,13 +31,13 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_LB_POLICY_GRPCLB_LOAD_BALANCER_API_H
-#define GRPC_CORE_EXT_LB_POLICY_GRPCLB_LOAD_BALANCER_API_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_LOAD_BALANCER_API_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_LOAD_BALANCER_API_H
 
 #include <grpc/slice_buffer.h>
 
-#include "src/core/ext/client_channel/lb_policy_factory.h"
-#include "src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h"
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -101,4 +101,5 @@ void grpc_grpclb_initial_response_destroy(
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_LB_POLICY_GRPCLB_LOAD_BALANCER_API_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_LOAD_BALANCER_API_H \
+          */
diff --git a/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c
index e352e0396f..e9adf98711 100644
--- a/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c
@@ -1,7 +1,7 @@
 /* Automatically generated nanopb constant definitions */
 /* Generated by nanopb-0.3.7-dev */
 
-#include "src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h"
 
 /* @@protoc_insertion_point(includes) */
 #if PB_PROTO_HEADER_VERSION != 30
diff --git a/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h
index 725aa7e386..725aa7e386 100644
--- a/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h
diff --git a/src/core/ext/lb_policy/pick_first/pick_first.c b/src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.c
index fc65dfdcb9..2b77cd39b8 100644
--- a/src/core/ext/lb_policy/pick_first/pick_first.c
+++ b/src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.c
@@ -35,8 +35,8 @@
 
 #include <grpc/support/alloc.h>
 
-#include "src/core/ext/client_channel/lb_policy_registry.h"
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/lb_policy_registry.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
@@ -402,7 +402,9 @@ static grpc_lb_policy *create_pick_first(grpc_exec_ctx *exec_ctx,
    * addresses, since we don't know how to handle them. */
   const grpc_arg *arg =
       grpc_channel_args_find(args->args, GRPC_ARG_LB_ADDRESSES);
-  GPR_ASSERT(arg != NULL && arg->type == GRPC_ARG_POINTER);
+  if (arg == NULL || arg->type != GRPC_ARG_POINTER) {
+    return NULL;
+  }
   grpc_lb_addresses *addresses = arg->value.pointer.p;
   size_t num_addrs = 0;
   for (size_t i = 0; i < addresses->num_addresses; i++) {
diff --git a/src/core/ext/lb_policy/round_robin/round_robin.c b/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.c
index a62082a2ff..ff41e61b3e 100644
--- a/src/core/ext/lb_policy/round_robin/round_robin.c
+++ b/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.c
@@ -63,8 +63,8 @@
 
 #include <grpc/support/alloc.h>
 
-#include "src/core/ext/client_channel/lb_policy_registry.h"
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/lb_policy_registry.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/iomgr/combiner.h"
@@ -691,7 +691,9 @@ static grpc_lb_policy *round_robin_create(grpc_exec_ctx *exec_ctx,
    * addresses, since we don't know how to handle them. */
   const grpc_arg *arg =
       grpc_channel_args_find(args->args, GRPC_ARG_LB_ADDRESSES);
-  GPR_ASSERT(arg != NULL && arg->type == GRPC_ARG_POINTER);
+  if (arg == NULL || arg->type != GRPC_ARG_POINTER) {
+    return NULL;
+  }
   grpc_lb_addresses *addresses = arg->value.pointer.p;
   size_t num_addrs = 0;
   for (size_t i = 0; i < addresses->num_addresses; i++) {
diff --git a/src/core/ext/client_channel/lb_policy_factory.c b/src/core/ext/filters/client_channel/lb_policy_factory.c
index 7af9bb0411..e2af216b89 100644
--- a/src/core/ext/client_channel/lb_policy_factory.c
+++ b/src/core/ext/filters/client_channel/lb_policy_factory.c
@@ -36,7 +36,7 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 
 grpc_lb_addresses* grpc_lb_addresses_create(
     size_t num_addresses, const grpc_lb_user_data_vtable* user_data_vtable) {
diff --git a/src/core/ext/client_channel/lb_policy_factory.h b/src/core/ext/filters/client_channel/lb_policy_factory.h
index 27c12c0d73..81ab12ec8f 100644
--- a/src/core/ext/client_channel/lb_policy_factory.h
+++ b/src/core/ext/filters/client_channel/lb_policy_factory.h
@@ -31,11 +31,11 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_FACTORY_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_FACTORY_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_FACTORY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_FACTORY_H
 
-#include "src/core/ext/client_channel/client_channel_factory.h"
-#include "src/core/ext/client_channel/lb_policy.h"
+#include "src/core/ext/filters/client_channel/client_channel_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy.h"
 
 #include "src/core/lib/iomgr/exec_ctx.h"
 #include "src/core/lib/iomgr/resolve_address.h"
@@ -131,4 +131,4 @@ grpc_lb_policy *grpc_lb_policy_factory_create_lb_policy(
     grpc_exec_ctx *exec_ctx, grpc_lb_policy_factory *factory,
     grpc_lb_policy_args *args);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_FACTORY_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_FACTORY_H */
diff --git a/src/core/ext/client_channel/lb_policy_registry.c b/src/core/ext/filters/client_channel/lb_policy_registry.c
index 90c149d947..1376673bca 100644
--- a/src/core/ext/client_channel/lb_policy_registry.c
+++ b/src/core/ext/filters/client_channel/lb_policy_registry.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/lb_policy_registry.h"
+#include "src/core/ext/filters/client_channel/lb_policy_registry.h"
 
 #include <string.h>
 
diff --git a/src/core/ext/client_channel/lb_policy_registry.h b/src/core/ext/filters/client_channel/lb_policy_registry.h
index 21c468e021..dfdec1347f 100644
--- a/src/core/ext/client_channel/lb_policy_registry.h
+++ b/src/core/ext/filters/client_channel/lb_policy_registry.h
@@ -31,10 +31,10 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_REGISTRY_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_REGISTRY_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_REGISTRY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_REGISTRY_H
 
-#include "src/core/ext/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 #include "src/core/lib/iomgr/exec_ctx.h"
 
 /** Initialize the registry and set \a default_factory as the factory to be
@@ -52,4 +52,4 @@ void grpc_register_lb_policy(grpc_lb_policy_factory *factory);
 grpc_lb_policy *grpc_lb_policy_create(grpc_exec_ctx *exec_ctx, const char *name,
                                       grpc_lb_policy_args *args);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_LB_POLICY_REGISTRY_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_REGISTRY_H */
diff --git a/src/core/ext/client_channel/parse_address.c b/src/core/ext/filters/client_channel/parse_address.c
index cd1b2cd80c..0c97062075 100644
--- a/src/core/ext/client_channel/parse_address.c
+++ b/src/core/ext/filters/client_channel/parse_address.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/parse_address.h"
+#include "src/core/ext/filters/client_channel/parse_address.h"
 #include "src/core/lib/iomgr/sockaddr.h"
 
 #include <stdio.h>
diff --git a/src/core/ext/client_channel/parse_address.h b/src/core/ext/filters/client_channel/parse_address.h
index bf99c5298a..c8d77baa00 100644
--- a/src/core/ext/client_channel/parse_address.h
+++ b/src/core/ext/filters/client_channel/parse_address.h
@@ -31,12 +31,12 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_PARSE_ADDRESS_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_PARSE_ADDRESS_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PARSE_ADDRESS_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PARSE_ADDRESS_H
 
 #include <stddef.h>
 
-#include "src/core/ext/client_channel/uri_parser.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 
 /** Populate \a addr and \a len from \a uri, whose path is expected to contain a
@@ -51,4 +51,4 @@ int parse_ipv4(grpc_uri *uri, grpc_resolved_address *resolved_addr);
  * host:port pair. Returns true upon success. */
 int parse_ipv6(grpc_uri *uri, grpc_resolved_address *resolved_addr);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_PARSE_ADDRESS_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PARSE_ADDRESS_H */
diff --git a/src/core/ext/client_channel/proxy_mapper.c b/src/core/ext/filters/client_channel/proxy_mapper.c
index f92afe847b..6dddd3c6da 100644
--- a/src/core/ext/client_channel/proxy_mapper.c
+++ b/src/core/ext/filters/client_channel/proxy_mapper.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/proxy_mapper.h"
+#include "src/core/ext/filters/client_channel/proxy_mapper.h"
 
 void grpc_proxy_mapper_init(const grpc_proxy_mapper_vtable* vtable,
                             grpc_proxy_mapper* mapper) {
diff --git a/src/core/ext/client_channel/proxy_mapper.h b/src/core/ext/filters/client_channel/proxy_mapper.h
index 6e4607fe4d..d0c47d3090 100644
--- a/src/core/ext/client_channel/proxy_mapper.h
+++ b/src/core/ext/filters/client_channel/proxy_mapper.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_PROXY_MAPPER_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_PROXY_MAPPER_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_H
 
 #include <stdbool.h>
 
@@ -86,4 +86,4 @@ bool grpc_proxy_mapper_map_address(grpc_exec_ctx* exec_ctx,
 
 void grpc_proxy_mapper_destroy(grpc_proxy_mapper* mapper);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_PROXY_MAPPER_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_H */
diff --git a/src/core/ext/client_channel/proxy_mapper_registry.c b/src/core/ext/filters/client_channel/proxy_mapper_registry.c
index 0935ddbdbd..7a39289a84 100644
--- a/src/core/ext/client_channel/proxy_mapper_registry.c
+++ b/src/core/ext/filters/client_channel/proxy_mapper_registry.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/proxy_mapper_registry.h"
+#include "src/core/ext/filters/client_channel/proxy_mapper_registry.h"
 
 #include <string.h>
 
diff --git a/src/core/ext/client_channel/proxy_mapper_registry.h b/src/core/ext/filters/client_channel/proxy_mapper_registry.h
index 742b57a2d4..8b5686d664 100644
--- a/src/core/ext/client_channel/proxy_mapper_registry.h
+++ b/src/core/ext/filters/client_channel/proxy_mapper_registry.h
@@ -31,10 +31,10 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_PROXY_MAPPER_REGISTRY_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_PROXY_MAPPER_REGISTRY_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_REGISTRY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_REGISTRY_H
 
-#include "src/core/ext/client_channel/proxy_mapper.h"
+#include "src/core/ext/filters/client_channel/proxy_mapper.h"
 
 void grpc_proxy_mapper_registry_init();
 void grpc_proxy_mapper_registry_shutdown();
@@ -56,4 +56,4 @@ bool grpc_proxy_mappers_map_address(grpc_exec_ctx* exec_ctx,
                                     grpc_resolved_address** new_address,
                                     grpc_channel_args** new_args);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_PROXY_MAPPER_REGISTRY_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_REGISTRY_H */
diff --git a/src/core/ext/client_channel/resolver.c b/src/core/ext/filters/client_channel/resolver.c
index b1a1faa6c9..cafa2837f3 100644
--- a/src/core/ext/client_channel/resolver.c
+++ b/src/core/ext/filters/client_channel/resolver.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/resolver.h"
+#include "src/core/ext/filters/client_channel/resolver.h"
 #include "src/core/lib/iomgr/combiner.h"
 
 void grpc_resolver_init(grpc_resolver *resolver,
diff --git a/src/core/ext/client_channel/resolver.h b/src/core/ext/filters/client_channel/resolver.h
index bbba424ca5..55f9124b3a 100644
--- a/src/core/ext/client_channel/resolver.h
+++ b/src/core/ext/filters/client_channel/resolver.h
@@ -31,10 +31,10 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_H
 
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 #include "src/core/lib/iomgr/iomgr.h"
 
 typedef struct grpc_resolver grpc_resolver;
@@ -98,4 +98,4 @@ void grpc_resolver_next_locked(grpc_exec_ctx *exec_ctx, grpc_resolver *resolver,
                                grpc_channel_args **result,
                                grpc_closure *on_complete);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_H */
diff --git a/src/core/ext/resolver/README.md b/src/core/ext/filters/client_channel/resolver/README.md
index b0e234e96a..b0e234e96a 100644
--- a/src/core/ext/resolver/README.md
+++ b/src/core/ext/filters/client_channel/resolver/README.md
diff --git a/src/core/ext/resolver/dns/c_ares/dns_resolver_ares.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
index f27da231f5..ffaeeed324 100644
--- a/src/core/ext/resolver/dns/c_ares/dns_resolver_ares.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
@@ -40,10 +40,10 @@
 #include <grpc/support/host_port.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/http_connect_handshaker.h"
-#include "src/core/ext/client_channel/lb_policy_registry.h"
-#include "src/core/ext/client_channel/resolver_registry.h"
-#include "src/core/ext/resolver/dns/c_ares/grpc_ares_wrapper.h"
+#include "src/core/ext/filters/client_channel/http_connect_handshaker.h"
+#include "src/core/ext/filters/client_channel/lb_policy_registry.h"
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/resolve_address.h"
diff --git a/src/core/ext/resolver/dns/c_ares/grpc_ares_ev_driver.h b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h
index 334feaa2ab..aa88940021 100644
--- a/src/core/ext/resolver/dns/c_ares/grpc_ares_ev_driver.h
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H
-#define GRPC_CORE_EXT_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H
 
 #include <ares.h>
 
@@ -62,4 +62,5 @@ grpc_error *grpc_ares_ev_driver_create(grpc_ares_ev_driver **ev_driver,
    of ARES_ECANCELLED. */
 void grpc_ares_ev_driver_destroy(grpc_ares_ev_driver *ev_driver);
 
-#endif /* GRPC_CORE_EXT_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H \
+          */
diff --git a/src/core/ext/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
index fab4f0c977..1e4f3eb5ab 100644
--- a/src/core/ext/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
@@ -34,14 +34,14 @@
 #include "src/core/lib/iomgr/port.h"
 #if GRPC_ARES == 1 && defined(GRPC_POSIX_SOCKET)
 
-#include "src/core/ext/resolver/dns/c_ares/grpc_ares_ev_driver.h"
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h"
 
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 #include <grpc/support/time.h>
 #include <grpc/support/useful.h>
-#include "src/core/ext/resolver/dns/c_ares/grpc_ares_wrapper.h"
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h"
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
diff --git a/src/core/ext/resolver/dns/c_ares/grpc_ares_wrapper.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c
index 3eee8e3513..09c46a66e0 100644
--- a/src/core/ext/resolver/dns/c_ares/grpc_ares_wrapper.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c
@@ -34,7 +34,7 @@
 #include <grpc/support/port_platform.h>
 #if GRPC_ARES == 1 && !defined(GRPC_UV)
 
-#include "src/core/ext/resolver/dns/c_ares/grpc_ares_wrapper.h"
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h"
 #include "src/core/lib/iomgr/sockaddr.h"
 #include "src/core/lib/iomgr/socket_utils_posix.h"
 
@@ -48,7 +48,7 @@
 #include <grpc/support/string_util.h>
 #include <grpc/support/time.h>
 #include <grpc/support/useful.h>
-#include "src/core/ext/resolver/dns/c_ares/grpc_ares_ev_driver.h"
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h"
 #include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
diff --git a/src/core/ext/resolver/dns/c_ares/grpc_ares_wrapper.h b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h
index ab00a26b36..3dd40ea268 100644
--- a/src/core/ext/resolver/dns/c_ares/grpc_ares_wrapper.h
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H
-#define GRPC_CORE_EXT_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H
 
 #include "src/core/lib/iomgr/exec_ctx.h"
 #include "src/core/lib/iomgr/iomgr.h"
@@ -60,4 +60,5 @@ grpc_error *grpc_ares_init(void);
    it has been called the same number of times as grpc_ares_init(). */
 void grpc_ares_cleanup(void);
 
-#endif /* GRPC_CORE_EXT_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H \
+          */
diff --git a/src/core/ext/resolver/dns/native/README.md b/src/core/ext/filters/client_channel/resolver/dns/native/README.md
index 695de47b9f..695de47b9f 100644
--- a/src/core/ext/resolver/dns/native/README.md
+++ b/src/core/ext/filters/client_channel/resolver/dns/native/README.md
diff --git a/src/core/ext/resolver/dns/native/dns_resolver.c b/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.c
index 97cd0486a9..ebe6a07215 100644
--- a/src/core/ext/resolver/dns/native/dns_resolver.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.c
@@ -37,8 +37,8 @@
 #include <grpc/support/host_port.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/lb_policy_registry.h"
-#include "src/core/ext/client_channel/resolver_registry.h"
+#include "src/core/ext/filters/client_channel/lb_policy_registry.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/resolve_address.h"
diff --git a/src/core/ext/resolver/sockaddr/README.md b/src/core/ext/filters/client_channel/resolver/sockaddr/README.md
index e307ba88f5..e307ba88f5 100644
--- a/src/core/ext/resolver/sockaddr/README.md
+++ b/src/core/ext/filters/client_channel/resolver/sockaddr/README.md
diff --git a/src/core/ext/resolver/sockaddr/sockaddr_resolver.c b/src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c
index da5923d26f..54f020d691 100644
--- a/src/core/ext/resolver/sockaddr/sockaddr_resolver.c
+++ b/src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c
@@ -41,9 +41,9 @@
 #include <grpc/support/port_platform.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/lb_policy_factory.h"
-#include "src/core/ext/client_channel/parse_address.h"
-#include "src/core/ext/client_channel/resolver_registry.h"
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/parse_address.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/resolve_address.h"
diff --git a/src/core/ext/client_channel/resolver_factory.c b/src/core/ext/filters/client_channel/resolver_factory.c
index 00bbb92dd0..07f9e4cf03 100644
--- a/src/core/ext/client_channel/resolver_factory.c
+++ b/src/core/ext/filters/client_channel/resolver_factory.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/resolver_factory.h"
+#include "src/core/ext/filters/client_channel/resolver_factory.h"
 
 void grpc_resolver_factory_ref(grpc_resolver_factory* factory) {
   factory->vtable->ref(factory);
diff --git a/src/core/ext/client_channel/resolver_factory.h b/src/core/ext/filters/client_channel/resolver_factory.h
index e3cd99ec5a..f2fcfc06fe 100644
--- a/src/core/ext/client_channel/resolver_factory.h
+++ b/src/core/ext/filters/client_channel/resolver_factory.h
@@ -31,12 +31,12 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_FACTORY_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_FACTORY_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FACTORY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FACTORY_H
 
-#include "src/core/ext/client_channel/client_channel_factory.h"
-#include "src/core/ext/client_channel/resolver.h"
-#include "src/core/ext/client_channel/uri_parser.h"
+#include "src/core/ext/filters/client_channel/client_channel_factory.h"
+#include "src/core/ext/filters/client_channel/resolver.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
 #include "src/core/lib/iomgr/pollset_set.h"
 
 typedef struct grpc_resolver_factory grpc_resolver_factory;
@@ -82,4 +82,4 @@ grpc_resolver *grpc_resolver_factory_create_resolver(
 char *grpc_resolver_factory_get_default_authority(
     grpc_resolver_factory *factory, grpc_uri *uri);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_FACTORY_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FACTORY_H */
diff --git a/src/core/ext/client_channel/resolver_registry.c b/src/core/ext/filters/client_channel/resolver_registry.c
index 0f074a3386..fa997bd68f 100644
--- a/src/core/ext/client_channel/resolver_registry.c
+++ b/src/core/ext/filters/client_channel/resolver_registry.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/resolver_registry.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
 
 #include <string.h>
 
diff --git a/src/core/ext/client_channel/resolver_registry.h b/src/core/ext/filters/client_channel/resolver_registry.h
index 1a3ebee25a..f2e9f9249c 100644
--- a/src/core/ext/client_channel/resolver_registry.h
+++ b/src/core/ext/filters/client_channel/resolver_registry.h
@@ -31,10 +31,10 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_REGISTRY_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_REGISTRY_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_REGISTRY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_REGISTRY_H
 
-#include "src/core/ext/client_channel/resolver_factory.h"
+#include "src/core/ext/filters/client_channel/resolver_factory.h"
 #include "src/core/lib/iomgr/pollset_set.h"
 
 void grpc_resolver_registry_init();
@@ -81,4 +81,4 @@ char *grpc_get_default_authority(grpc_exec_ctx *exec_ctx, const char *target);
 char *grpc_resolver_factory_add_default_prefix_if_needed(
     grpc_exec_ctx *exec_ctx, const char *target);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_RESOLVER_REGISTRY_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_REGISTRY_H */
diff --git a/src/core/ext/client_channel/retry_throttle.c b/src/core/ext/filters/client_channel/retry_throttle.c
index 8926c3d782..dd78a17844 100644
--- a/src/core/ext/client_channel/retry_throttle.c
+++ b/src/core/ext/filters/client_channel/retry_throttle.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/retry_throttle.h"
+#include "src/core/ext/filters/client_channel/retry_throttle.h"
 
 #include <limits.h>
 #include <string.h>
diff --git a/src/core/ext/client_channel/retry_throttle.h b/src/core/ext/filters/client_channel/retry_throttle.h
index f9971faf65..640865cf90 100644
--- a/src/core/ext/client_channel/retry_throttle.h
+++ b/src/core/ext/filters/client_channel/retry_throttle.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_RETRY_THROTTLE_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_RETRY_THROTTLE_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RETRY_THROTTLE_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RETRY_THROTTLE_H
 
 #include <stdbool.h>
 
@@ -62,4 +62,4 @@ void grpc_retry_throttle_map_shutdown();
 grpc_server_retry_throttle_data* grpc_retry_throttle_map_get_data_for_server(
     const char* server_name, int max_milli_tokens, int milli_token_ratio);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_RETRY_THROTTLE_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RETRY_THROTTLE_H */
diff --git a/src/core/ext/client_channel/subchannel.c b/src/core/ext/filters/client_channel/subchannel.c
index 063c0badff..dd3ca06239 100644
--- a/src/core/ext/client_channel/subchannel.c
+++ b/src/core/ext/filters/client_channel/subchannel.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 
 #include <limits.h>
 #include <string.h>
@@ -40,11 +40,11 @@
 #include <grpc/support/avl.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/client_channel/parse_address.h"
-#include "src/core/ext/client_channel/proxy_mapper_registry.h"
-#include "src/core/ext/client_channel/subchannel_index.h"
-#include "src/core/ext/client_channel/uri_parser.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/parse_address.h"
+#include "src/core/ext/filters/client_channel/proxy_mapper_registry.h"
+#include "src/core/ext/filters/client_channel/subchannel_index.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
@@ -360,7 +360,6 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
     for (size_t i = 0; i < c->args->num_args; i++) {
       if (0 == strcmp(c->args->args[i].key,
                       "grpc.testing.fixed_reconnect_backoff_ms")) {
-        GPR_ASSERT(c->args->args[i].type == GRPC_ARG_INTEGER);
         fixed_reconnect_backoff = true;
         initial_backoff_ms = min_backoff_ms = max_backoff_ms =
             grpc_channel_arg_get_integer(
diff --git a/src/core/ext/client_channel/subchannel.h b/src/core/ext/filters/client_channel/subchannel.h
index 3e64a2507c..7a638e8b2e 100644
--- a/src/core/ext/client_channel/subchannel.h
+++ b/src/core/ext/filters/client_channel/subchannel.h
@@ -31,10 +31,10 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_SUBCHANNEL_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_SUBCHANNEL_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_H
 
-#include "src/core/ext/client_channel/connector.h"
+#include "src/core/ext/filters/client_channel/connector.h"
 #include "src/core/lib/channel/channel_stack.h"
 #include "src/core/lib/iomgr/polling_entity.h"
 #include "src/core/lib/support/arena.h"
@@ -200,4 +200,4 @@ const char *grpc_get_subchannel_address_uri_arg(const grpc_channel_args *args);
 /// Caller is responsible for freeing the string.
 grpc_arg grpc_create_subchannel_address_arg(const grpc_resolved_address *addr);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_SUBCHANNEL_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_H */
diff --git a/src/core/ext/client_channel/subchannel_index.c b/src/core/ext/filters/client_channel/subchannel_index.c
index 11889300a2..f6ef4a845e 100644
--- a/src/core/ext/client_channel/subchannel_index.c
+++ b/src/core/ext/filters/client_channel/subchannel_index.c
@@ -31,7 +31,7 @@
 //
 //
 
-#include "src/core/ext/client_channel/subchannel_index.h"
+#include "src/core/ext/filters/client_channel/subchannel_index.h"
 
 #include <stdbool.h>
 #include <string.h>
diff --git a/src/core/ext/client_channel/subchannel_index.h b/src/core/ext/filters/client_channel/subchannel_index.h
index a67bd5e219..f673ade378 100644
--- a/src/core/ext/client_channel/subchannel_index.h
+++ b/src/core/ext/filters/client_channel/subchannel_index.h
@@ -31,11 +31,11 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H
 
-#include "src/core/ext/client_channel/connector.h"
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/connector.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 
 /** \file Provides an index of active subchannels so that they can be
     shared amongst channels */
@@ -74,4 +74,4 @@ void grpc_subchannel_index_init(void);
 /** Shutdown the subchannel index (global) */
 void grpc_subchannel_index_shutdown(void);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H */
diff --git a/src/core/ext/client_channel/uri_parser.c b/src/core/ext/filters/client_channel/uri_parser.c
index d385db0801..01b99911aa 100644
--- a/src/core/ext/client_channel/uri_parser.c
+++ b/src/core/ext/filters/client_channel/uri_parser.c
@@ -31,7 +31,7 @@
  *
  */
 
-#include "src/core/ext/client_channel/uri_parser.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
 
 #include <string.h>
 
diff --git a/src/core/ext/client_channel/uri_parser.h b/src/core/ext/filters/client_channel/uri_parser.h
index efd4302c1c..2698d448d8 100644
--- a/src/core/ext/client_channel/uri_parser.h
+++ b/src/core/ext/filters/client_channel/uri_parser.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_URI_PARSER_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_URI_PARSER_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_URI_PARSER_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_URI_PARSER_H
 
 #include <stddef.h>
 #include "src/core/lib/iomgr/exec_ctx.h"
@@ -62,4 +62,4 @@ const char *grpc_uri_get_query_arg(const grpc_uri *uri, const char *key);
 /** destroy a uri */
 void grpc_uri_destroy(grpc_uri *uri);
 
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_URI_PARSER_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_URI_PARSER_H */
diff --git a/src/core/ext/load_reporting/load_reporting.c b/src/core/ext/filters/load_reporting/load_reporting.c
index 942aea4fd1..9fb33bab71 100644
--- a/src/core/ext/load_reporting/load_reporting.c
+++ b/src/core/ext/filters/load_reporting/load_reporting.c
@@ -38,8 +38,8 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/sync.h>
 
-#include "src/core/ext/load_reporting/load_reporting.h"
-#include "src/core/ext/load_reporting/load_reporting_filter.h"
+#include "src/core/ext/filters/load_reporting/load_reporting.h"
+#include "src/core/ext/filters/load_reporting/load_reporting_filter.h"
 #include "src/core/lib/channel/channel_stack_builder.h"
 #include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/surface/call.h"
diff --git a/src/core/ext/load_reporting/load_reporting.h b/src/core/ext/filters/load_reporting/load_reporting.h
index 22859a599a..e05a9dcc71 100644
--- a/src/core/ext/load_reporting/load_reporting.h
+++ b/src/core/ext/filters/load_reporting/load_reporting.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_H
-#define GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_H
+#ifndef GRPC_CORE_EXT_FILTERS_LOAD_REPORTING_LOAD_REPORTING_H
+#define GRPC_CORE_EXT_FILTERS_LOAD_REPORTING_LOAD_REPORTING_H
 
 #include <grpc/impl/codegen/grpc_types.h>
 
@@ -70,4 +70,4 @@ typedef struct grpc_load_reporting_call_data {
 /** Return a \a grpc_arg enabling load reporting */
 grpc_arg grpc_load_reporting_enable_arg();
 
-#endif /* GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_H */
+#endif /* GRPC_CORE_EXT_FILTERS_LOAD_REPORTING_LOAD_REPORTING_H */
diff --git a/src/core/ext/load_reporting/load_reporting_filter.c b/src/core/ext/filters/load_reporting/load_reporting_filter.c
index ea57c85c3a..7870ec0c4f 100644
--- a/src/core/ext/load_reporting/load_reporting_filter.c
+++ b/src/core/ext/filters/load_reporting/load_reporting_filter.c
@@ -39,8 +39,8 @@
 #include <grpc/support/string_util.h>
 #include <grpc/support/sync.h>
 
-#include "src/core/ext/load_reporting/load_reporting.h"
-#include "src/core/ext/load_reporting/load_reporting_filter.h"
+#include "src/core/ext/filters/load_reporting/load_reporting.h"
+#include "src/core/ext/filters/load_reporting/load_reporting_filter.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/slice/slice_internal.h"
diff --git a/src/core/ext/load_reporting/load_reporting_filter.h b/src/core/ext/filters/load_reporting/load_reporting_filter.h
index 160ed32af9..da884a1479 100644
--- a/src/core/ext/load_reporting/load_reporting_filter.h
+++ b/src/core/ext/filters/load_reporting/load_reporting_filter.h
@@ -31,12 +31,12 @@
  *
  */
 
-#ifndef GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_FILTER_H
-#define GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_FILTER_H
+#ifndef GRPC_CORE_EXT_FILTERS_LOAD_REPORTING_LOAD_REPORTING_FILTER_H
+#define GRPC_CORE_EXT_FILTERS_LOAD_REPORTING_LOAD_REPORTING_FILTER_H
 
-#include "src/core/ext/load_reporting/load_reporting.h"
+#include "src/core/ext/filters/load_reporting/load_reporting.h"
 #include "src/core/lib/channel/channel_stack.h"
 
 extern const grpc_channel_filter grpc_load_reporting_filter;
 
-#endif /* GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_FILTER_H */
+#endif /* GRPC_CORE_EXT_FILTERS_LOAD_REPORTING_LOAD_REPORTING_FILTER_H */
diff --git a/src/core/ext/filters/max_age/max_age_filter.c b/src/core/ext/filters/max_age/max_age_filter.c
new file mode 100644
index 0000000000..b03cb0ba0a
--- /dev/null
+++ b/src/core/ext/filters/max_age/max_age_filter.c
@@ -0,0 +1,419 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/lib/channel/message_size_filter.h"
+
+#include <limits.h>
+#include <string.h>
+
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/channel/channel_stack_builder.h"
+#include "src/core/lib/iomgr/timer.h"
+#include "src/core/lib/surface/channel_init.h"
+#include "src/core/lib/transport/http2_errors.h"
+#include "src/core/lib/transport/service_config.h"
+
+#define DEFAULT_MAX_CONNECTION_AGE_MS INT_MAX
+#define DEFAULT_MAX_CONNECTION_AGE_GRACE_MS INT_MAX
+#define DEFAULT_MAX_CONNECTION_IDLE_MS INT_MAX
+
+typedef struct channel_data {
+  /* We take a reference to the channel stack for the timer callback */
+  grpc_channel_stack* channel_stack;
+  /* Guards access to max_age_timer, max_age_timer_pending, max_age_grace_timer
+     and max_age_grace_timer_pending */
+  gpr_mu max_age_timer_mu;
+  /* True if the max_age timer callback is currently pending */
+  bool max_age_timer_pending;
+  /* True if the max_age_grace timer callback is currently pending */
+  bool max_age_grace_timer_pending;
+  /* The timer for checking if the channel has reached its max age */
+  grpc_timer max_age_timer;
+  /* The timer for checking if the max-aged channel has uesed up the grace
+     period */
+  grpc_timer max_age_grace_timer;
+  /* The timer for checking if the channel's idle duration reaches
+     max_connection_idle */
+  grpc_timer max_idle_timer;
+  /* Allowed max time a channel may have no outstanding rpcs */
+  gpr_timespec max_connection_idle;
+  /* Allowed max time a channel may exist */
+  gpr_timespec max_connection_age;
+  /* Allowed grace period after the channel reaches its max age */
+  gpr_timespec max_connection_age_grace;
+  /* Closure to run when the channel's idle duration reaches max_connection_idle
+     and should be closed gracefully */
+  grpc_closure close_max_idle_channel;
+  /* Closure to run when the channel reaches its max age and should be closed
+     gracefully */
+  grpc_closure close_max_age_channel;
+  /* Closure to run the channel uses up its max age grace time and should be
+     closed forcibly */
+  grpc_closure force_close_max_age_channel;
+  /* Closure to run when the init fo channel stack is done and the max_idle
+     timer should be started */
+  grpc_closure start_max_idle_timer_after_init;
+  /* Closure to run when the init fo channel stack is done and the max_age timer
+     should be started */
+  grpc_closure start_max_age_timer_after_init;
+  /* Closure to run when the goaway op is finished and the max_age_timer */
+  grpc_closure start_max_age_grace_timer_after_goaway_op;
+  /* Closure to run when the channel connectivity state changes */
+  grpc_closure channel_connectivity_changed;
+  /* Records the current connectivity state */
+  grpc_connectivity_state connectivity_state;
+  /* Number of active calls */
+  gpr_atm call_count;
+} channel_data;
+
+/* Increase the nubmer of active calls. Before the increasement, if there are no
+   calls, the max_idle_timer should be cancelled. */
+static void increase_call_count(grpc_exec_ctx* exec_ctx, channel_data* chand) {
+  if (gpr_atm_full_fetch_add(&chand->call_count, 1) == 0) {
+    grpc_timer_cancel(exec_ctx, &chand->max_idle_timer);
+  }
+}
+
+/* Decrease the nubmer of active calls. After the decrement, if there are no
+   calls, the max_idle_timer should be started. */
+static void decrease_call_count(grpc_exec_ctx* exec_ctx, channel_data* chand) {
+  if (gpr_atm_full_fetch_add(&chand->call_count, -1) == 1) {
+    GRPC_CHANNEL_STACK_REF(chand->channel_stack, "max_age max_idle_timer");
+    grpc_timer_init(
+        exec_ctx, &chand->max_idle_timer,
+        gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC), chand->max_connection_idle),
+        &chand->close_max_idle_channel, gpr_now(GPR_CLOCK_MONOTONIC));
+  }
+}
+
+static void start_max_idle_timer_after_init(grpc_exec_ctx* exec_ctx, void* arg,
+                                            grpc_error* error) {
+  channel_data* chand = arg;
+  /* Decrease call_count. If there are no active calls at this time,
+     max_idle_timer will start here. If the number of active calls is not 0,
+     max_idle_timer will start after all the active calls end. */
+  decrease_call_count(exec_ctx, chand);
+  GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->channel_stack,
+                           "max_age start_max_idle_timer_after_init");
+}
+
+static void start_max_age_timer_after_init(grpc_exec_ctx* exec_ctx, void* arg,
+                                           grpc_error* error) {
+  channel_data* chand = arg;
+  gpr_mu_lock(&chand->max_age_timer_mu);
+  chand->max_age_timer_pending = true;
+  GRPC_CHANNEL_STACK_REF(chand->channel_stack, "max_age max_age_timer");
+  grpc_timer_init(
+      exec_ctx, &chand->max_age_timer,
+      gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC), chand->max_connection_age),
+      &chand->close_max_age_channel, gpr_now(GPR_CLOCK_MONOTONIC));
+  gpr_mu_unlock(&chand->max_age_timer_mu);
+  grpc_transport_op* op = grpc_make_transport_op(NULL);
+  op->on_connectivity_state_change = &chand->channel_connectivity_changed,
+  op->connectivity_state = &chand->connectivity_state;
+  grpc_channel_next_op(exec_ctx,
+                       grpc_channel_stack_element(chand->channel_stack, 0), op);
+  GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->channel_stack,
+                           "max_age start_max_age_timer_after_init");
+}
+
+static void start_max_age_grace_timer_after_goaway_op(grpc_exec_ctx* exec_ctx,
+                                                      void* arg,
+                                                      grpc_error* error) {
+  channel_data* chand = arg;
+  gpr_mu_lock(&chand->max_age_timer_mu);
+  chand->max_age_grace_timer_pending = true;
+  GRPC_CHANNEL_STACK_REF(chand->channel_stack, "max_age max_age_grace_timer");
+  grpc_timer_init(exec_ctx, &chand->max_age_grace_timer,
+                  gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC),
+                               chand->max_connection_age_grace),
+                  &chand->force_close_max_age_channel,
+                  gpr_now(GPR_CLOCK_MONOTONIC));
+  gpr_mu_unlock(&chand->max_age_timer_mu);
+  GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->channel_stack,
+                           "max_age start_max_age_grace_timer_after_goaway_op");
+}
+
+static void close_max_idle_channel(grpc_exec_ctx* exec_ctx, void* arg,
+                                   grpc_error* error) {
+  channel_data* chand = arg;
+  gpr_atm_no_barrier_fetch_add(&chand->call_count, 1);
+  if (error == GRPC_ERROR_NONE) {
+    grpc_transport_op* op = grpc_make_transport_op(NULL);
+    op->goaway_error =
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING("max_idle"),
+                           GRPC_ERROR_INT_HTTP2_ERROR, GRPC_HTTP2_NO_ERROR);
+    grpc_channel_element* elem =
+        grpc_channel_stack_element(chand->channel_stack, 0);
+    elem->filter->start_transport_op(exec_ctx, elem, op);
+  } else if (error != GRPC_ERROR_CANCELLED) {
+    GRPC_LOG_IF_ERROR("close_max_idle_channel", error);
+  }
+  GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->channel_stack,
+                           "max_age max_idle_timer");
+}
+
+static void close_max_age_channel(grpc_exec_ctx* exec_ctx, void* arg,
+                                  grpc_error* error) {
+  channel_data* chand = arg;
+  gpr_mu_lock(&chand->max_age_timer_mu);
+  chand->max_age_timer_pending = false;
+  gpr_mu_unlock(&chand->max_age_timer_mu);
+  if (error == GRPC_ERROR_NONE) {
+    GRPC_CHANNEL_STACK_REF(chand->channel_stack,
+                           "max_age start_max_age_grace_timer_after_goaway_op");
+    grpc_transport_op* op = grpc_make_transport_op(
+        &chand->start_max_age_grace_timer_after_goaway_op);
+    op->goaway_error =
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING("max_age"),
+                           GRPC_ERROR_INT_HTTP2_ERROR, GRPC_HTTP2_NO_ERROR);
+    grpc_channel_element* elem =
+        grpc_channel_stack_element(chand->channel_stack, 0);
+    elem->filter->start_transport_op(exec_ctx, elem, op);
+  } else if (error != GRPC_ERROR_CANCELLED) {
+    GRPC_LOG_IF_ERROR("close_max_age_channel", error);
+  }
+  GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->channel_stack,
+                           "max_age max_age_timer");
+}
+
+static void force_close_max_age_channel(grpc_exec_ctx* exec_ctx, void* arg,
+                                        grpc_error* error) {
+  channel_data* chand = arg;
+  gpr_mu_lock(&chand->max_age_timer_mu);
+  chand->max_age_grace_timer_pending = false;
+  gpr_mu_unlock(&chand->max_age_timer_mu);
+  if (error == GRPC_ERROR_NONE) {
+    grpc_transport_op* op = grpc_make_transport_op(NULL);
+    op->disconnect_with_error =
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel reaches max age");
+    grpc_channel_element* elem =
+        grpc_channel_stack_element(chand->channel_stack, 0);
+    elem->filter->start_transport_op(exec_ctx, elem, op);
+  } else if (error != GRPC_ERROR_CANCELLED) {
+    GRPC_LOG_IF_ERROR("force_close_max_age_channel", error);
+  }
+  GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->channel_stack,
+                           "max_age max_age_grace_timer");
+}
+
+static void channel_connectivity_changed(grpc_exec_ctx* exec_ctx, void* arg,
+                                         grpc_error* error) {
+  channel_data* chand = arg;
+  if (chand->connectivity_state != GRPC_CHANNEL_SHUTDOWN) {
+    grpc_transport_op* op = grpc_make_transport_op(NULL);
+    op->on_connectivity_state_change = &chand->channel_connectivity_changed,
+    op->connectivity_state = &chand->connectivity_state;
+    grpc_channel_next_op(
+        exec_ctx, grpc_channel_stack_element(chand->channel_stack, 0), op);
+  } else {
+    gpr_mu_lock(&chand->max_age_timer_mu);
+    if (chand->max_age_timer_pending) {
+      grpc_timer_cancel(exec_ctx, &chand->max_age_timer);
+      chand->max_age_timer_pending = false;
+    }
+    if (chand->max_age_grace_timer_pending) {
+      grpc_timer_cancel(exec_ctx, &chand->max_age_grace_timer);
+      chand->max_age_grace_timer_pending = false;
+    }
+    gpr_mu_unlock(&chand->max_age_timer_mu);
+    /* If there are no active calls, this increasement will cancel
+       max_idle_timer, and prevent max_idle_timer from being started in the
+       future. */
+    increase_call_count(exec_ctx, chand);
+  }
+}
+
+/* Constructor for call_data. */
+static grpc_error* init_call_elem(grpc_exec_ctx* exec_ctx,
+                                  grpc_call_element* elem,
+                                  const grpc_call_element_args* args) {
+  channel_data* chand = elem->channel_data;
+  increase_call_count(exec_ctx, chand);
+  return GRPC_ERROR_NONE;
+}
+
+/* Destructor for call_data. */
+static void destroy_call_elem(grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
+                              const grpc_call_final_info* final_info,
+                              grpc_closure* ignored) {
+  channel_data* chand = elem->channel_data;
+  decrease_call_count(exec_ctx, chand);
+}
+
+/* Constructor for channel_data. */
+static grpc_error* init_channel_elem(grpc_exec_ctx* exec_ctx,
+                                     grpc_channel_element* elem,
+                                     grpc_channel_element_args* args) {
+  channel_data* chand = elem->channel_data;
+  gpr_mu_init(&chand->max_age_timer_mu);
+  chand->max_age_timer_pending = false;
+  chand->max_age_grace_timer_pending = false;
+  chand->channel_stack = args->channel_stack;
+  chand->max_connection_age =
+      DEFAULT_MAX_CONNECTION_AGE_MS == INT_MAX
+          ? gpr_inf_future(GPR_TIMESPAN)
+          : gpr_time_from_millis(DEFAULT_MAX_CONNECTION_AGE_MS, GPR_TIMESPAN);
+  chand->max_connection_age_grace =
+      DEFAULT_MAX_CONNECTION_AGE_GRACE_MS == INT_MAX
+          ? gpr_inf_future(GPR_TIMESPAN)
+          : gpr_time_from_millis(DEFAULT_MAX_CONNECTION_AGE_GRACE_MS,
+                                 GPR_TIMESPAN);
+  chand->max_connection_idle =
+      DEFAULT_MAX_CONNECTION_IDLE_MS == INT_MAX
+          ? gpr_inf_future(GPR_TIMESPAN)
+          : gpr_time_from_millis(DEFAULT_MAX_CONNECTION_IDLE_MS, GPR_TIMESPAN);
+  for (size_t i = 0; i < args->channel_args->num_args; ++i) {
+    if (0 == strcmp(args->channel_args->args[i].key,
+                    GRPC_ARG_MAX_CONNECTION_AGE_MS)) {
+      const int value = grpc_channel_arg_get_integer(
+          &args->channel_args->args[i],
+          (grpc_integer_options){DEFAULT_MAX_CONNECTION_AGE_MS, 1, INT_MAX});
+      chand->max_connection_age =
+          value == INT_MAX ? gpr_inf_future(GPR_TIMESPAN)
+                           : gpr_time_from_millis(value, GPR_TIMESPAN);
+    } else if (0 == strcmp(args->channel_args->args[i].key,
+                           GRPC_ARG_MAX_CONNECTION_AGE_GRACE_MS)) {
+      const int value = grpc_channel_arg_get_integer(
+          &args->channel_args->args[i],
+          (grpc_integer_options){DEFAULT_MAX_CONNECTION_AGE_GRACE_MS, 0,
+                                 INT_MAX});
+      chand->max_connection_age_grace =
+          value == INT_MAX ? gpr_inf_future(GPR_TIMESPAN)
+                           : gpr_time_from_millis(value, GPR_TIMESPAN);
+    } else if (0 == strcmp(args->channel_args->args[i].key,
+                           GRPC_ARG_MAX_CONNECTION_IDLE_MS)) {
+      const int value = grpc_channel_arg_get_integer(
+          &args->channel_args->args[i],
+          (grpc_integer_options){DEFAULT_MAX_CONNECTION_IDLE_MS, 1, INT_MAX});
+      chand->max_connection_idle =
+          value == INT_MAX ? gpr_inf_future(GPR_TIMESPAN)
+                           : gpr_time_from_millis(value, GPR_TIMESPAN);
+    }
+  }
+  grpc_closure_init(&chand->close_max_idle_channel, close_max_idle_channel,
+                    chand, grpc_schedule_on_exec_ctx);
+  grpc_closure_init(&chand->close_max_age_channel, close_max_age_channel, chand,
+                    grpc_schedule_on_exec_ctx);
+  grpc_closure_init(&chand->force_close_max_age_channel,
+                    force_close_max_age_channel, chand,
+                    grpc_schedule_on_exec_ctx);
+  grpc_closure_init(&chand->start_max_idle_timer_after_init,
+                    start_max_idle_timer_after_init, chand,
+                    grpc_schedule_on_exec_ctx);
+  grpc_closure_init(&chand->start_max_age_timer_after_init,
+                    start_max_age_timer_after_init, chand,
+                    grpc_schedule_on_exec_ctx);
+  grpc_closure_init(&chand->start_max_age_grace_timer_after_goaway_op,
+                    start_max_age_grace_timer_after_goaway_op, chand,
+                    grpc_schedule_on_exec_ctx);
+  grpc_closure_init(&chand->channel_connectivity_changed,
+                    channel_connectivity_changed, chand,
+                    grpc_schedule_on_exec_ctx);
+
+  if (gpr_time_cmp(chand->max_connection_age, gpr_inf_future(GPR_TIMESPAN)) !=
+      0) {
+    /* When the channel reaches its max age, we send down an op with
+       goaway_error set.  However, we can't send down any ops until after the
+       channel stack is fully initialized.  If we start the timer here, we have
+       no guarantee that the timer won't pop before channel stack initialization
+       is finished.  To avoid that problem, we create a closure to start the
+       timer, and we schedule that closure to be run after call stack
+       initialization is done. */
+    GRPC_CHANNEL_STACK_REF(chand->channel_stack,
+                           "max_age start_max_age_timer_after_init");
+    grpc_closure_sched(exec_ctx, &chand->start_max_age_timer_after_init,
+                       GRPC_ERROR_NONE);
+  }
+
+  /* Initialize the number of calls as 1, so that the max_idle_timer will not
+     start until start_max_idle_timer_after_init is invoked. */
+  gpr_atm_rel_store(&chand->call_count, 1);
+  if (gpr_time_cmp(chand->max_connection_idle, gpr_inf_future(GPR_TIMESPAN)) !=
+      0) {
+    GRPC_CHANNEL_STACK_REF(chand->channel_stack,
+                           "max_age start_max_idle_timer_after_init");
+    grpc_closure_sched(exec_ctx, &chand->start_max_idle_timer_after_init,
+                       GRPC_ERROR_NONE);
+  }
+  return GRPC_ERROR_NONE;
+}
+
+/* Destructor for channel_data. */
+static void destroy_channel_elem(grpc_exec_ctx* exec_ctx,
+                                 grpc_channel_element* elem) {}
+
+const grpc_channel_filter grpc_max_age_filter = {
+    grpc_call_next_op,
+    grpc_channel_next_op,
+    0, /* sizeof_call_data */
+    init_call_elem,
+    grpc_call_stack_ignore_set_pollset_or_pollset_set,
+    destroy_call_elem,
+    sizeof(channel_data),
+    init_channel_elem,
+    destroy_channel_elem,
+    grpc_call_next_get_peer,
+    grpc_channel_next_get_info,
+    "max_age"};
+
+static bool maybe_add_max_age_filter(grpc_exec_ctx* exec_ctx,
+                                     grpc_channel_stack_builder* builder,
+                                     void* arg) {
+  const grpc_channel_args* channel_args =
+      grpc_channel_stack_builder_get_channel_arguments(builder);
+  const grpc_arg* a =
+      grpc_channel_args_find(channel_args, GRPC_ARG_MAX_CONNECTION_AGE_MS);
+  bool enable = false;
+  if (a != NULL && a->type == GRPC_ARG_INTEGER && a->value.integer != INT_MAX) {
+    enable = true;
+  }
+  a = grpc_channel_args_find(channel_args, GRPC_ARG_MAX_CONNECTION_IDLE_MS);
+  if (a != NULL && a->type == GRPC_ARG_INTEGER && a->value.integer != INT_MAX) {
+    enable = true;
+  }
+  if (enable) {
+    return grpc_channel_stack_builder_prepend_filter(
+        builder, &grpc_max_age_filter, NULL, NULL);
+  } else {
+    return true;
+  }
+}
+
+void grpc_max_age_filter_init(void) {
+  grpc_channel_init_register_stage(GRPC_SERVER_CHANNEL,
+                                   GRPC_CHANNEL_INIT_BUILTIN_PRIORITY,
+                                   maybe_add_max_age_filter, NULL);
+}
+
+void grpc_max_age_filter_shutdown(void) {}
diff --git a/src/core/ext/filters/max_age/max_age_filter.h b/src/core/ext/filters/max_age/max_age_filter.h
new file mode 100644
index 0000000000..ed2015297a
--- /dev/null
+++ b/src/core/ext/filters/max_age/max_age_filter.h
@@ -0,0 +1,39 @@
+//
+// Copyright 2017, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+
+#ifndef GRPC_CORE_EXT_FILTERS_MAX_AGE_MAX_AGE_FILTER_H
+#define GRPC_CORE_EXT_FILTERS_MAX_AGE_MAX_AGE_FILTER_H
+
+#include "src/core/lib/channel/channel_stack.h"
+
+extern const grpc_channel_filter grpc_max_age_filter;
+
+#endif /* GRPC_CORE_EXT_FILTERS_MAX_AGE_MAX_AGE_FILTER_H */
diff --git a/src/core/ext/transport/chttp2/client/chttp2_connector.c b/src/core/ext/transport/chttp2/client/chttp2_connector.c
index 2b226c1bf7..e645eda7e3 100644
--- a/src/core/ext/transport/chttp2/client/chttp2_connector.c
+++ b/src/core/ext/transport/chttp2/client/chttp2_connector.c
@@ -41,9 +41,9 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/connector.h"
-#include "src/core/ext/client_channel/http_connect_handshaker.h"
-#include "src/core/ext/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/connector.h"
+#include "src/core/ext/filters/client_channel/http_connect_handshaker.h"
+#include "src/core/ext/filters/client_channel/subchannel.h"
 #include "src/core/ext/transport/chttp2/transport/chttp2_transport.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/handshaker.h"
diff --git a/src/core/ext/transport/chttp2/client/chttp2_connector.h b/src/core/ext/transport/chttp2/client/chttp2_connector.h
index f5d1025432..d55f6ed669 100644
--- a/src/core/ext/transport/chttp2/client/chttp2_connector.h
+++ b/src/core/ext/transport/chttp2/client/chttp2_connector.h
@@ -34,7 +34,7 @@
 #ifndef GRPC_CORE_EXT_TRANSPORT_CHTTP2_CLIENT_CHTTP2_CONNECTOR_H
 #define GRPC_CORE_EXT_TRANSPORT_CHTTP2_CLIENT_CHTTP2_CONNECTOR_H
 
-#include "src/core/ext/client_channel/connector.h"
+#include "src/core/ext/filters/client_channel/connector.h"
 
 grpc_connector* grpc_chttp2_connector_create();
 
diff --git a/src/core/ext/transport/chttp2/client/insecure/channel_create.c b/src/core/ext/transport/chttp2/client/insecure/channel_create.c
index 067ac35a5a..9c8505ddfa 100644
--- a/src/core/ext/transport/chttp2/client/insecure/channel_create.c
+++ b/src/core/ext/transport/chttp2/client/insecure/channel_create.c
@@ -38,8 +38,8 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/client_channel/resolver_registry.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
 #include "src/core/ext/transport/chttp2/client/chttp2_connector.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/surface/api_trace.h"
diff --git a/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c b/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
index f0c241d68e..119adfade1 100644
--- a/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
+++ b/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
@@ -38,9 +38,9 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/client_channel/resolver_registry.h"
-#include "src/core/ext/client_channel/uri_parser.h"
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
 #include "src/core/ext/transport/chttp2/client/chttp2_connector.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"