# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1616713410 -3600
# Node ID 84bc31650a9a086b524919f0b2eb9e64e822d9b3
# Parent  3e4d7c4e617e5f2bc775cadd098b19a7691a91b3
Introduced support for closing pipe resources.

diff -r 3e4d7c4e617e -r 84bc31650a9a files/pipe_paging.cc
--- a/files/pipe_paging.cc	Thu Mar 25 01:42:50 2021 +0100
+++ b/files/pipe_paging.cc	Fri Mar 26 00:03:30 2021 +0100
@@ -5,6 +5,30 @@
 {
 }
 
+/* Detach one endpoint. */
+
+void PipePaging::detach()
+{
+    if (!_endpoints)
+        return;
+    else
+        _endpoints--;
+
+    if (_endpoints)
+        return;
+
+    /* Discard all regions from the pipe. */
+
+    while (!_regions.empty())
+    {
+        PageMapper *mapper = _regions.front();
+
+        _regions.pop_front();
+        mapper->detach();
+        delete mapper;
+    }
+}
+
 /* Add a region to the sequence. */
 
 void PipePaging::add_region(PageMapper *mapper)
@@ -31,7 +55,16 @@
         if (_accessors.size() > _regions.size())
             _accessors.pop_front();
 
+        /* Detach and discard the current page mapper. */
+
+        PageMapper *mapper = _regions.front();
+
         _regions.pop_front();
+        mapper->detach();
+        delete mapper;
+
+        /* Return the next region. */
+
         return _regions.front();
     }
     else
diff -r 3e4d7c4e617e -r 84bc31650a9a files/pipe_paging.h
--- a/files/pipe_paging.h	Thu Mar 25 01:42:50 2021 +0100
+++ b/files/pipe_paging.h	Fri Mar 26 00:03:30 2021 +0100
@@ -23,9 +23,23 @@
 
     offset_t _size;
 
+    /* Endpoint status. */
+
+    unsigned int _endpoints = 2;
+
 public:
     explicit PipePaging(offset_t size);
 
+    virtual void detach();
+
+    virtual PagesConserving *pages()
+    { return &_pages; }
+
+    virtual offset_t region_size()
+    { return _size; }
+
+    /* Region management. */
+
     virtual void add_region(PageMapper *mapper);
 
     virtual PageMapper *first_region();
@@ -33,12 +47,6 @@
     virtual PageMapper *next_region();
 
     virtual PipeAccessor *accessor();
-
-    virtual PagesConserving *pages()
-    { return &_pages; }
-
-    virtual offset_t region_size()
-    { return _size; }
 };
 
 // vim: tabstop=4 expandtab shiftwidth=4
diff -r 3e4d7c4e617e -r 84bc31650a9a pipe_pager.cc
--- a/pipe_pager.cc	Thu Mar 25 01:42:50 2021 +0100
+++ b/pipe_pager.cc	Fri Mar 26 00:03:30 2021 +0100
@@ -26,6 +26,14 @@
 
 
 
+/* Close the pager, releasing the paging coordinator for the pipe. This will
+   release all active page mappers. */
+
+void PipePager::close()
+{
+    _paging->detach();
+}
+
 /* Support paging. */
 
 long PipePager::map(unsigned long offset, l4_addr_t hot_spot, flags_t flags, l4_snd_fpage_t *region)
@@ -74,11 +82,6 @@
         if (mapper == NULL)
             return -L4_EIO;
 
-        /* Detach and discard the current page mapper. */
-
-        _mapper->detach();
-        delete _mapper;
-
         _mapper = mapper;
     }
 
diff -r 3e4d7c4e617e -r 84bc31650a9a pipe_pager.h
--- a/pipe_pager.h	Thu Mar 25 01:42:50 2021 +0100
+++ b/pipe_pager.h	Fri Mar 26 00:03:30 2021 +0100
@@ -22,6 +22,8 @@
 public:
     explicit PipePager(PipePaging *paging, bool writer);
 
+    virtual void close();
+
     /* Server details. */
 
     int expected_items();