+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _BCACHEFS_TWO_STATE_LOCK_H
-#define _BCACHEFS_TWO_STATE_LOCK_H
-
-#include <linux/atomic.h>
-#include <linux/sched.h>
-#include <linux/wait.h>
-
-#include "util.h"
-
-/*
- * Two-state lock - can be taken for add or block - both states are shared,
- * like read side of rwsem, but conflict with other state:
- */
-typedef struct {
- atomic_long_t v;
- wait_queue_head_t wait;
-} two_state_lock_t;
-
-static inline void two_state_lock_init(two_state_lock_t *lock)
-{
- atomic_long_set(&lock->v, 0);
- init_waitqueue_head(&lock->wait);
-}
-
-static inline void bch2_two_state_unlock(two_state_lock_t *lock, int s)
-{
- long i = s ? 1 : -1;
-
- EBUG_ON(atomic_long_read(&lock->v) == 0);
-
- if (atomic_long_sub_return_release(i, &lock->v) == 0)
- wake_up_all(&lock->wait);
-}
-
-static inline bool bch2_two_state_trylock(two_state_lock_t *lock, int s)
-{
- long i = s ? 1 : -1;
- long v = atomic_long_read(&lock->v), old;
-
- do {
- old = v;
-
- if (i > 0 ? v < 0 : v > 0)
- return false;
- } while ((v = atomic_long_cmpxchg_acquire(&lock->v,
- old, old + i)) != old);
- return true;
-}
-
-void __bch2_two_state_lock(two_state_lock_t *, int);
-
-static inline void bch2_two_state_lock(two_state_lock_t *lock, int s)
-{
- if (!bch2_two_state_trylock(lock, s))
- __bch2_two_state_lock(lock, s);
-}
-
-#endif /* _BCACHEFS_TWO_STATE_LOCK_H */