GFS2: Use lockref for glocks

[platform/adaptation/renesas_rcar/renesas_kernel.git] / include / linux / lockref.h

diff --git a/include/linux/lockref.h b/include/linux/lockref.h
index 01233e0..13dfd36 100644 (file)
--- a/include/linux/lockref.h
+++ b/include/linux/lockref.h
@@ -17,55 +17,29 @@
 #include <linux/spinlock.h>
 
 struct lockref {
-       spinlock_t lock;
-       unsigned int count;
+       union {
+#ifdef CONFIG_CMPXCHG_LOCKREF
+               aligned_u64 lock_count;
+#endif
+               struct {
+                       spinlock_t lock;
+                       unsigned int count;
+               };
+       };
 };
 
-/**
- * lockref_get - Increments reference count unconditionally
- * @lockcnt: pointer to lockref structure
- *
- * This operation is only valid if you already hold a reference
- * to the object, so you know the count cannot be zero.
- */
-static inline void lockref_get(struct lockref *lockref)
-{
-       spin_lock(&lockref->lock);
-       lockref->count++;
-       spin_unlock(&lockref->lock);
-}
+extern void lockref_get(struct lockref *);
+extern int lockref_get_not_zero(struct lockref *);
+extern int lockref_get_or_lock(struct lockref *);
+extern int lockref_put_or_lock(struct lockref *);
 
-/**
- * lockref_get_not_zero - Increments count unless the count is 0
- * @lockcnt: pointer to lockref structure
- * Return: 1 if count updated successfully or 0 if count is 0
- */
-static inline int lockref_get_not_zero(struct lockref *lockref)
-{
-       int retval = 0;
-
-       spin_lock(&lockref->lock);
-       if (lockref->count) {
-               lockref->count++;
-               retval = 1;
-       }
-       spin_unlock(&lockref->lock);
-       return retval;
-}
+extern void lockref_mark_dead(struct lockref *);
+extern int lockref_get_not_dead(struct lockref *);
 
-/**
- * lockref_put_or_lock - decrements count unless count <= 1 before decrement
- * @lockcnt: pointer to lockref structure
- * Return: 1 if count updated successfully or 0 if count <= 1 and lock taken
- */
-static inline int lockref_put_or_lock(struct lockref *lockref)
+/* Must be called under spinlock for reliable results */
+static inline int __lockref_is_dead(const struct lockref *l)
 {
-       spin_lock(&lockref->lock);
-       if (lockref->count <= 1)
-               return 0;
-       lockref->count--;
-       spin_unlock(&lockref->lock);
-       return 1;
+       return ((int)l->count < 0);
 }
 
 #endif /* __LINUX_LOCKREF_H */