X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fxen%2Fxenbus%2Fxenbus_backend_client.c;fp=drivers%2Fxen%2Fxenbus%2Fxenbus_backend_client.c;h=b99991cdabcf11c4352d042f9d57f5736b9dd808;hb=1db395853d4f30d6120458bd279ede1f882a8525;hp=0000000000000000000000000000000000000000;hpb=34a75f0025b9cf803b6a88db032e6ad6950c9313;p=linux-2.6.git

diff --git a/drivers/xen/xenbus/xenbus_backend_client.c b/drivers/xen/xenbus/xenbus_backend_client.c
new file mode 100644
index 000000000..b99991cda
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_backend_client.c
@@ -0,0 +1,135 @@
+/******************************************************************************
+ * Backend-client-facing interface for the Xenbus driver.  In other words, the
+ * interface between the Xenbus and the device-specific code in the backend
+ * driver.
+ *
+ * Copyright (C) 2005-2006 XenSource Ltd
+ * 
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/err.h>
+#include <xen/gnttab.h>
+#include <xen/xenbus.h>
+#include <xen/driver_util.h>
+
+/* Based on Rusty Russell's skeleton driver's map_page */
+struct vm_struct *xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref)
+{
+	struct gnttab_map_grant_ref op;
+	struct vm_struct *area;
+
+	area = alloc_vm_area(PAGE_SIZE);
+	if (!area)
+		return ERR_PTR(-ENOMEM);
+
+	gnttab_set_map_op(&op, (unsigned long)area->addr, GNTMAP_host_map,
+			  gnt_ref, dev->otherend_id);
+	
+	lock_vm_area(area);
+	BUG_ON(HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1));
+	unlock_vm_area(area);
+
+	if (op.status != GNTST_okay) {
+		free_vm_area(area);
+		xenbus_dev_fatal(dev, op.status,
+				 "mapping in shared page %d from domain %d",
+				 gnt_ref, dev->otherend_id);
+		BUG_ON(!IS_ERR(ERR_PTR(op.status)));
+		return ERR_PTR(op.status);
+	}
+
+	/* Stuff the handle in an unused field */
+	area->phys_addr = (unsigned long)op.handle;
+
+	return area;
+}
+EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc);
+
+
+int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
+		   grant_handle_t *handle, void *vaddr)
+{
+	struct gnttab_map_grant_ref op;
+	
+	gnttab_set_map_op(&op, (unsigned long)vaddr, GNTMAP_host_map,
+			  gnt_ref, dev->otherend_id);
+	BUG_ON(HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1));
+
+	if (op.status != GNTST_okay) {
+		xenbus_dev_fatal(dev, op.status,
+				 "mapping in shared page %d from domain %d",
+				 gnt_ref, dev->otherend_id);
+	} else
+		*handle = op.handle;
+
+	return op.status;
+}
+EXPORT_SYMBOL_GPL(xenbus_map_ring);
+
+
+/* Based on Rusty Russell's skeleton driver's unmap_page */
+int xenbus_unmap_ring_vfree(struct xenbus_device *dev, struct vm_struct *area)
+{
+	struct gnttab_unmap_grant_ref op;
+
+	gnttab_set_unmap_op(&op, (unsigned long)area->addr, GNTMAP_host_map,
+			    (grant_handle_t)area->phys_addr);
+
+	lock_vm_area(area);
+	BUG_ON(HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1));
+	unlock_vm_area(area);
+
+	if (op.status == GNTST_okay)
+		free_vm_area(area);
+	else
+		xenbus_dev_error(dev, op.status,
+				 "unmapping page at handle %d error %d",
+				 (int16_t)area->phys_addr, op.status);
+
+	return op.status;
+}
+EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);
+
+
+int xenbus_unmap_ring(struct xenbus_device *dev,
+		     grant_handle_t handle, void *vaddr)
+{
+	struct gnttab_unmap_grant_ref op;
+
+	gnttab_set_unmap_op(&op, (unsigned long)vaddr, GNTMAP_host_map,
+			    handle);
+	BUG_ON(HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1));
+
+	if (op.status != GNTST_okay)
+		xenbus_dev_error(dev, op.status,
+				 "unmapping page at handle %d error %d",
+				 handle, op.status);
+
+	return op.status;
+}
+EXPORT_SYMBOL_GPL(xenbus_unmap_ring);
+
+MODULE_LICENSE("Dual BSD/GPL");