firmware_class: Do not warn that system is not ready from async loads

[cascardo/linux.git] / kernel / kmod.c

diff --git a/kernel/kmod.c b/kernel/kmod.c
index 4079ac1..da7fcca 100644 (file)
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -333,6 +333,12 @@ static atomic_t running_helpers = ATOMIC_INIT(0);
  */
 static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq);
 
+/*
+ * Used by usermodehelper_read_lock_wait() to wait for usermodehelper_disabled
+ * to become 'false'.
+ */
+static DECLARE_WAIT_QUEUE_HEAD(usermodehelper_disabled_waitq);
+
 /*
  * Time to wait for running_helpers to become zero before the setting of
  * usermodehelper_disabled in usermodehelper_disable() fails
@@ -352,12 +358,50 @@ int usermodehelper_read_trylock(void)
 }
 EXPORT_SYMBOL_GPL(usermodehelper_read_trylock);
 
+long usermodehelper_read_lock_wait(long timeout)
+{
+       DEFINE_WAIT(wait);
+
+       if (timeout < 0)
+               return -EINVAL;
+
+       down_read(&umhelper_sem);
+       for (;;) {
+               prepare_to_wait(&usermodehelper_disabled_waitq, &wait,
+                               TASK_UNINTERRUPTIBLE);
+               if (!usermodehelper_disabled)
+                       break;
+
+               up_read(&umhelper_sem);
+
+               timeout = schedule_timeout(timeout);
+               if (!timeout)
+                       break;
+
+               down_read(&umhelper_sem);
+       }
+       finish_wait(&usermodehelper_disabled_waitq, &wait);
+       return timeout;
+}
+EXPORT_SYMBOL_GPL(usermodehelper_read_lock_wait);
+
 void usermodehelper_read_unlock(void)
 {
        up_read(&umhelper_sem);
 }
 EXPORT_SYMBOL_GPL(usermodehelper_read_unlock);
 
+/**
+ * usermodehelper_enable - allow new helpers to be started again
+ */
+void usermodehelper_enable(void)
+{
+       down_write(&umhelper_sem);
+       usermodehelper_disabled = 0;
+       wake_up(&usermodehelper_disabled_waitq);
+       up_write(&umhelper_sem);
+}
+
 /**
  * usermodehelper_disable - prevent new helpers from being started
  */
@@ -381,22 +425,10 @@ int usermodehelper_disable(void)
        if (retval)
                return 0;
 
-       down_write(&umhelper_sem);
-       usermodehelper_disabled = 0;
-       up_write(&umhelper_sem);
+       usermodehelper_enable();
        return -EAGAIN;
 }
 
-/**
- * usermodehelper_enable - allow new helpers to be started again
- */
-void usermodehelper_enable(void)
-{
-       down_write(&umhelper_sem);
-       usermodehelper_disabled = 0;
-       up_write(&umhelper_sem);
-}
-
 static void helper_lock(void)
 {
        atomic_inc(&running_helpers);