diff --git a/src/mesa/main/dd.h b/src/mesa/main/dd.h
index 8216752ccaf..7a39f939c97 100644
--- a/src/mesa/main/dd.h
+++ b/src/mesa/main/dd.h
@@ -1156,14 +1156,24 @@ struct dd_function_table {
     * server's command stream
     */
    void (*ServerWaitSemaphoreObject)(struct gl_context *ctx,
-                                     struct gl_semaphore_object *semObj);
+                                     struct gl_semaphore_object *semObj,
+                                     GLuint numBufferBarriers,
+                                     struct gl_buffer_object **bufObjs,
+                                     GLuint numTextureBarriers,
+                                     struct gl_texture_object **texObjs,
+                                     const GLenum *srcLayouts);
 
    /**
     * Introduce an operation to signal the semaphore object in the GL
     * server's command stream
     */
    void (*ServerSignalSemaphoreObject)(struct gl_context *ctx,
-                                       struct gl_semaphore_object *semObj);
+                                       struct gl_semaphore_object *semObj,
+                                       GLuint numBufferBarriers,
+                                       struct gl_buffer_object **bufObjs,
+                                       GLuint numTextureBarriers,
+                                       struct gl_texture_object **texObjs,
+                                       const GLenum *dstLayouts);
    /*@}*/
 
    /**
diff --git a/src/mesa/main/externalobjects.c b/src/mesa/main/externalobjects.c
index 9ba70c8e7f8..8f31ba4c354 100644
--- a/src/mesa/main/externalobjects.c
+++ b/src/mesa/main/externalobjects.c
@@ -23,6 +23,7 @@
 
 #include "macros.h"
 #include "mtypes.h"
+#include "bufferobj.h"
 #include "context.h"
 #include "externalobjects.h"
 #include "teximage.h"
@@ -716,7 +717,8 @@ _mesa_WaitSemaphoreEXT(GLuint semaphore,
 {
    GET_CURRENT_CONTEXT(ctx);
    struct gl_semaphore_object *semObj;
-
+   struct gl_buffer_object **bufObjs;
+   struct gl_texture_object **texObjs;
 
    if (!ctx->Extensions.EXT_semaphore) {
       _mesa_error(ctx, GL_INVALID_OPERATION, "glWaitSemaphoreEXT(unsupported)");
@@ -732,8 +734,20 @@ _mesa_WaitSemaphoreEXT(GLuint semaphore,
    FLUSH_VERTICES(ctx, 0);
    FLUSH_CURRENT(ctx, 0);
 
-   /* TODO: memory barriers and layout transitions */
-   ctx->Driver.ServerWaitSemaphoreObject(ctx, semObj);
+   bufObjs = alloca(sizeof(struct gl_buffer_object **) * numBufferBarriers);
+   for (unsigned i = 0; i < numBufferBarriers; i++) {
+      bufObjs[i] = _mesa_lookup_bufferobj(ctx, buffers[i]);
+   }
+
+   texObjs = alloca(sizeof(struct gl_texture_object **) * numTextureBarriers);
+   for (unsigned i = 0; i < numTextureBarriers; i++) {
+      texObjs[i] = _mesa_lookup_texture(ctx, textures[i]);
+   }
+
+   ctx->Driver.ServerWaitSemaphoreObject(ctx, semObj,
+                                         numBufferBarriers, bufObjs,
+                                         numTextureBarriers, texObjs,
+                                         srcLayouts);
 }
 
 void GLAPIENTRY
@@ -746,6 +760,8 @@ _mesa_SignalSemaphoreEXT(GLuint semaphore,
 {
    GET_CURRENT_CONTEXT(ctx);
    struct gl_semaphore_object *semObj;
+   struct gl_buffer_object **bufObjs;
+   struct gl_texture_object **texObjs;
 
    if (!ctx->Extensions.EXT_semaphore) {
       _mesa_error(ctx, GL_INVALID_OPERATION, "glSignalSemaphoreEXT(unsupported)");
@@ -761,8 +777,20 @@ _mesa_SignalSemaphoreEXT(GLuint semaphore,
    FLUSH_VERTICES(ctx, 0);
    FLUSH_CURRENT(ctx, 0);
 
-   /* TODO: memory barriers and layout transitions */
-   ctx->Driver.ServerSignalSemaphoreObject(ctx, semObj);
+   bufObjs = alloca(sizeof(struct gl_buffer_object **) * numBufferBarriers);
+   for (unsigned i = 0; i < numBufferBarriers; i++) {
+      bufObjs[i] = _mesa_lookup_bufferobj(ctx, buffers[i]);
+   }
+
+   texObjs = alloca(sizeof(struct gl_texture_object **) * numTextureBarriers);
+   for (unsigned i = 0; i < numTextureBarriers; i++) {
+      texObjs[i] = _mesa_lookup_texture(ctx, textures[i]);
+   }
+
+   ctx->Driver.ServerSignalSemaphoreObject(ctx, semObj,
+                                           numBufferBarriers, bufObjs,
+                                           numTextureBarriers, texObjs,
+                                           dstLayouts);
 }
 
 void GLAPIENTRY
diff --git a/src/mesa/state_tracker/st_cb_semaphoreobjects.c b/src/mesa/state_tracker/st_cb_semaphoreobjects.c
index 0661e65eff8..4a3faf57538 100644
--- a/src/mesa/state_tracker/st_cb_semaphoreobjects.c
+++ b/src/mesa/state_tracker/st_cb_semaphoreobjects.c
@@ -23,10 +23,14 @@
 
 #include "main/imports.h"
 #include "main/mtypes.h"
+#include "main/context.h"
 
 #include "main/externalobjects.h"
 
 #include "st_context.h"
+#include "st_texture.h"
+#include "st_cb_bitmap.h"
+#include "st_cb_bufferobjects.h"
 #include "st_cb_semaphoreobjects.h"
 
 #include "state_tracker/drm_driver.h"
@@ -69,10 +73,95 @@ st_import_semaphoreobj_fd(struct gl_context *ctx,
 #endif
 }
 
+static void
+st_server_wait_semaphore(struct gl_context *ctx,
+                         struct gl_semaphore_object *semObj,
+                         GLuint numBufferBarriers,
+                         struct gl_buffer_object **bufObjs,
+                         GLuint numTextureBarriers,
+                         struct gl_texture_object **texObjs,
+                         const GLenum *srcLayouts)
+{
+   struct st_semaphore_object *st_obj = st_semaphore_object(semObj);
+   struct st_context *st = st_context(ctx);
+   struct pipe_context *pipe = st->pipe;
+   struct st_buffer_object *bufObj;
+   struct st_texture_object *texObj;
+
+   /* The driver is allowed to flush during fence_server_sync, be prepared */
+   st_flush_bitmap_cache(st);
+   pipe->fence_server_sync(pipe, st_obj->fence);
+
+   /**
+    * According to the EXT_external_objects spec, the memory operations must
+    * follow the wait. This is to make sure the flush is executed after the
+    * other party is done modifying the memory.
+    *
+    * Relevant excerpt from section "4.2.3 Waiting for Semaphores":
+    *
+    * Following completion of the semaphore wait operation, memory will also be
+    * made visible in the specified buffer and texture objects.
+    *
+    */
+   for (unsigned i = 0; i < numBufferBarriers; i++) {
+      if (!bufObjs[i])
+         continue;
+
+      bufObj = st_buffer_object(bufObjs[i]);
+      pipe->flush_resource(pipe, bufObj->buffer);
+   }
+
+   for (unsigned i = 0; i < numTextureBarriers; i++) {
+      if (!texObjs[i])
+         continue;
+
+      texObj = st_texture_object(texObjs[i]);
+      pipe->flush_resource(pipe, texObj->pt);
+   }
+}
+
+static void
+st_server_signal_semaphore(struct gl_context *ctx,
+                           struct gl_semaphore_object *semObj,
+                           GLuint numBufferBarriers,
+                           struct gl_buffer_object **bufObjs,
+                           GLuint numTextureBarriers,
+                           struct gl_texture_object **texObjs,
+                           const GLenum *dstLayouts)
+{
+   struct st_semaphore_object *st_obj = st_semaphore_object(semObj);
+   struct st_context *st = st_context(ctx);
+   struct pipe_context *pipe = st->pipe;
+   struct st_buffer_object *bufObj;
+   struct st_texture_object *texObj;
+
+   for (unsigned i = 0; i < numBufferBarriers; i++) {
+      if (!bufObjs[i])
+         continue;
+
+      bufObj = st_buffer_object(bufObjs[i]);
+      pipe->flush_resource(pipe, bufObj->buffer);
+   }
+
+   for (unsigned i = 0; i < numTextureBarriers; i++) {
+      if (!texObjs[i])
+         continue;
+
+      texObj = st_texture_object(texObjs[i]);
+      pipe->flush_resource(pipe, texObj->pt);
+   }
+
+   /* The driver is allowed to flush during fence_server_signal, be prepared */
+   st_flush_bitmap_cache(st);
+   pipe->fence_server_signal(pipe, st_obj->fence);
+}
+
 void
 st_init_semaphoreobject_functions(struct dd_function_table *functions)
 {
    functions->NewSemaphoreObject = st_semaphoreobj_alloc;
    functions->DeleteSemaphoreObject = st_semaphoreobj_free;
    functions->ImportSemaphoreFd = st_import_semaphoreobj_fd;
+   functions->ServerWaitSemaphoreObject = st_server_wait_semaphore;
+   functions->ServerSignalSemaphoreObject = st_server_signal_semaphore;
 }