pci-arbiter: Implement memory mapping over region files

* pci-arbiter/Makefile:
	* Add device_map.c to sources
* pci-arbiter/device_map.c:
* pci-arbiter/device_map.h:
	* New module for device mapping
	* Relies on libpciaccess mapping methods
* pci-arbiter/func_files.c:
	* io_region_file(): Use the new device mapping module
* pci-arbiter/netfs_impl.c:
	* Implements netfs_get_filemap():
		* Uses the device mapping module to map the region to the
		  arbiter space
		* Calls the kernel RPC vm_region_create_proxy() to obtain the
		  memory object proxy
		* Only region files are mapped for now
Message-Id: <20211219112647.11512-4-jlledom@mailfence.com>

1 files changed, 38 insertions, 0 deletions

diff --git a/pci-arbiter/device_map.c b/pci-arbiter/device_map.c
new file mode 100644
index 00000000..216adfb9
--- /dev/null
+++ b/pci-arbiter/device_map.c
@@ -0,0 +1,38 @@
+/*
+   Copyright (C) 2021 Free Software Foundation, Inc.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   The GNU Hurd is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with the GNU Hurd.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/* Implementation for device memory mapping functions */
+
+#include <pciaccess.h>
+
+#include "device_map.h"
+
+error_t
+device_map_region (struct pci_device *device, struct pci_mem_region *region)
+{
+  error_t err = 0;
+
+  if (region->memory == 0)
+    {
+      err = pci_device_map_range (device, region->base_addr, region->size,
+				  PCI_DEV_MAP_FLAG_WRITABLE, &region->memory);
+    }
+
+  return err;
+}