Merge commit 'v2.6.38-rc4' into spi/next

[karo-tx-linux.git] / include / linux / res_counter.h

diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h
index fcb9884df6181827120dcb64efd7a2104fd157d7..a5930cb6614577517223ba642854b78ba339197b 100644 (file)
--- a/include/linux/res_counter.h
+++ b/include/linux/res_counter.h
@@ -182,6 +182,26 @@ static inline bool res_counter_check_under_limit(struct res_counter *cnt)
        return ret;
 }
 
+/**
+ * res_counter_check_margin - check if the counter allows charging
+ * @cnt: the resource counter to check
+ * @bytes: the number of bytes to check the remaining space against
+ *
+ * Returns a boolean value on whether the counter can be charged
+ * @bytes or whether this would exceed the limit.
+ */
+static inline bool res_counter_check_margin(struct res_counter *cnt,
+                                           unsigned long bytes)
+{
+       bool ret;
+       unsigned long flags;
+
+       spin_lock_irqsave(&cnt->lock, flags);
+       ret = cnt->limit - cnt->usage >= bytes;
+       spin_unlock_irqrestore(&cnt->lock, flags);
+       return ret;
+}
+
 static inline bool res_counter_check_under_soft_limit(struct res_counter *cnt)
 {
        bool ret;