[Suspend2][ 10/11] [Suspend2] Get and put references to Suspend2 modules.

[Nigel Cunningham <nigel@suspend2.net>]

Functions to get and put references to suspend2 modules, to stop them being
unloaded while in use.

Signed-off-by: Nigel Cunningham <nigel@suspend2.net>

 kernel/power/modules.c |   36 +++++++++++++++++++++++++++++++++++-
 1 files changed, 35 insertions(+), 1 deletions(-)

diff --git a/kernel/power/modules.c b/kernel/power/modules.c
index d7c2076..5c5cbf0 100644
--- a/kernel/power/modules.c
+++ b/kernel/power/modules.c
@@ -288,6 +288,40 @@ struct suspend_module_ops *suspend_get_n
 	return suspend_active_writer;
 }
 
-	return len;
+/* suspend_get_modules
+ * 
+ * Take a reference to modules so they can't go away under us.
+ */
+
+int suspend_get_modules(void)
+{
+	struct suspend_module_ops *this_module;
+	
+	list_for_each_entry(this_module, &suspend_modules, module_list) {
+		if (!try_module_get(this_module->module)) {
+			/* Failed! Reverse gets and return error */
+			struct suspend_module_ops *this_module2;
+			list_for_each_entry(this_module2, &suspend_modules, module_list) {
+				if (this_module == this_module2)
+					return -EINVAL;
+				module_put(this_module2->module);
+			}
+		}
+	}
+
+	return 0;
+}
+
+/* suspend_put_modules
+ *
+ * Release our references to modules we used.
+ */
+
+void suspend_put_modules(void)
+{
+	struct suspend_module_ops *this_module;
+	
+	list_for_each_entry(this_module, &suspend_modules, module_list)
+		module_put(this_module->module);
 }
 

--
Nigel Cunningham		nigel at suspend2 dot net