1 files changed, 53 insertions, 55 deletions

diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index 1da768e5ef75..82b84e4daad1 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -14,43 +14,58 @@
 
 static void btrfs_assert_tree_read_locked(struct extent_buffer *eb);
 
-/*
- * if we currently have a spinning reader or writer lock
- * (indicated by the rw flag) this will bump the count
- * of blocking holders and drop the spinlock.
- */
-void btrfs_set_lock_blocking_rw(struct extent_buffer *eb, int rw)
+void btrfs_set_lock_blocking_read(struct extent_buffer *eb)
 {
 	/*
-	 * no lock is required.  The lock owner may change if
-	 * we have a read lock, but it won't change to or away
-	 * from us.  If we have the write lock, we are the owner
-	 * and it'll never change.
+	 * No lock is required.  The lock owner may change if we have a read
+	 * lock, but it won't change to or away from us.  If we have the write
+	 * lock, we are the owner and it'll never change.
 	 */
 	if (eb->lock_nested && current->pid == eb->lock_owner)
 		return;
-	if (rw == BTRFS_WRITE_LOCK) {
-		if (atomic_read(&eb->blocking_writers) == 0) {
-			WARN_ON(atomic_read(&eb->spinning_writers) != 1);
-			atomic_dec(&eb->spinning_writers);
-			btrfs_assert_tree_locked(eb);
-			atomic_inc(&eb->blocking_writers);
-			write_unlock(&eb->lock);
-		}
-	} else if (rw == BTRFS_READ_LOCK) {
-		btrfs_assert_tree_read_locked(eb);
-		atomic_inc(&eb->blocking_readers);
-		WARN_ON(atomic_read(&eb->spinning_readers) == 0);
-		atomic_dec(&eb->spinning_readers);
-		read_unlock(&eb->lock);
+	btrfs_assert_tree_read_locked(eb);
+	atomic_inc(&eb->blocking_readers);
+	WARN_ON(atomic_read(&eb->spinning_readers) == 0);
+	atomic_dec(&eb->spinning_readers);
+	read_unlock(&eb->lock);
+}
+
+void btrfs_set_lock_blocking_write(struct extent_buffer *eb)
+{
+	/*
+	 * No lock is required.  The lock owner may change if we have a read
+	 * lock, but it won't change to or away from us.  If we have the write
+	 * lock, we are the owner and it'll never change.
+	 */
+	if (eb->lock_nested && current->pid == eb->lock_owner)
+		return;
+	if (atomic_read(&eb->blocking_writers) == 0) {
+		WARN_ON(atomic_read(&eb->spinning_writers) != 1);
+		atomic_dec(&eb->spinning_writers);
+		btrfs_assert_tree_locked(eb);
+		atomic_inc(&eb->blocking_writers);
+		write_unlock(&eb->lock);
 	}
 }
 
-/*
- * if we currently have a blocking lock, take the spinlock
- * and drop our blocking count
- */
-void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw)
+void btrfs_clear_lock_blocking_read(struct extent_buffer *eb)
+{
+	/*
+	 * No lock is required.  The lock owner may change if we have a read
+	 * lock, but it won't change to or away from us.  If we have the write
+	 * lock, we are the owner and it'll never change.
+	 */
+	if (eb->lock_nested && current->pid == eb->lock_owner)
+		return;
+	BUG_ON(atomic_read(&eb->blocking_readers) == 0);
+	read_lock(&eb->lock);
+	atomic_inc(&eb->spinning_readers);
+	/* atomic_dec_and_test implies a barrier */
+	if (atomic_dec_and_test(&eb->blocking_readers))
+		cond_wake_up_nomb(&eb->read_lock_wq);
+}
+
+void btrfs_clear_lock_blocking_write(struct extent_buffer *eb)
 {
 	/*
 	 * no lock is required.  The lock owner may change if
@@ -60,23 +75,13 @@ void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw)
 	 */
 	if (eb->lock_nested && current->pid == eb->lock_owner)
 		return;
-
-	if (rw == BTRFS_WRITE_LOCK_BLOCKING) {
-		BUG_ON(atomic_read(&eb->blocking_writers) != 1);
-		write_lock(&eb->lock);
-		WARN_ON(atomic_read(&eb->spinning_writers));
-		atomic_inc(&eb->spinning_writers);
-		/* atomic_dec_and_test implies a barrier */
-		if (atomic_dec_and_test(&eb->blocking_writers))
-			cond_wake_up_nomb(&eb->write_lock_wq);
-	} else if (rw == BTRFS_READ_LOCK_BLOCKING) {
-		BUG_ON(atomic_read(&eb->blocking_readers) == 0);
-		read_lock(&eb->lock);
-		atomic_inc(&eb->spinning_readers);
-		/* atomic_dec_and_test implies a barrier */
-		if (atomic_dec_and_test(&eb->blocking_readers))
-			cond_wake_up_nomb(&eb->read_lock_wq);
-	}
+	BUG_ON(atomic_read(&eb->blocking_writers) != 1);
+	write_lock(&eb->lock);
+	WARN_ON(atomic_read(&eb->spinning_writers));
+	atomic_inc(&eb->spinning_writers);
+	/* atomic_dec_and_test implies a barrier */
+	if (atomic_dec_and_test(&eb->blocking_writers))
+		cond_wake_up_nomb(&eb->write_lock_wq);
 }
 
 /*
@@ -232,16 +237,9 @@ again:
 	wait_event(eb->read_lock_wq, atomic_read(&eb->blocking_readers) == 0);
 	wait_event(eb->write_lock_wq, atomic_read(&eb->blocking_writers) == 0);
 	write_lock(&eb->lock);
-	if (atomic_read(&eb->blocking_readers)) {
+	if (atomic_read(&eb->blocking_readers) ||
+	    atomic_read(&eb->blocking_writers)) {
 		write_unlock(&eb->lock);
-		wait_event(eb->read_lock_wq,
-			   atomic_read(&eb->blocking_readers) == 0);
-		goto again;
-	}
-	if (atomic_read(&eb->blocking_writers)) {
-		write_unlock(&eb->lock);
-		wait_event(eb->write_lock_wq,
-			   atomic_read(&eb->blocking_writers) == 0);
 		goto again;
 	}
 	WARN_ON(atomic_read(&eb->spinning_writers));