# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1663365825 -7200
# Node ID f0bb79dd52dd2ce960815ee1e03d0960862d9adc
# Parent  750d75411ead94fa556d9a315003f130b9996123
Employ a paging region size compatible with the configured page size. Without
this, the mapping mechanism fails to generate valid send flexpages.

diff -r 750d75411ead -r f0bb79dd52dd libfsserver/lib/pipes/pipe_paging.cc
--- a/libfsserver/lib/pipes/pipe_paging.cc	Fri Sep 16 22:59:39 2022 +0200
+++ b/libfsserver/lib/pipes/pipe_paging.cc	Sat Sep 17 00:03:45 2022 +0200
@@ -1,7 +1,7 @@
 /*
  * A pipe paging coordinator, permitting memory sharing pipe endpoints.
  *
- * Copyright (C) 2021 Paul Boddie <paul@boddie.org.uk>
+ * Copyright (C) 2021, 2022 Paul Boddie <paul@boddie.org.uk>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -19,6 +19,8 @@
  * Boston, MA  02110-1301, USA
  */
 
+#include <algorithm>
+
 #include <mem/memory_preallocated.h>
 
 #include "page_queue_partitioned.h"
@@ -27,8 +29,12 @@
 
 
 PipePaging::PipePaging(Memory *memory, offset_t size)
-: NotificationSupport(2), _memory(NULL), _size(size)
+: NotificationSupport(2), _memory(NULL)
 {
+    /* Employ a region size compatible with the configured page size. */
+
+    _size = std::max<offset_t>(size, PAGE_SIZE);
+
     /* Reserve space for two pipe regions. */
 
     _memory = new MemoryPreallocated(memory, round(size, memory->region_size()) * 2);