fs/btrfs/locking.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (C) 2008 Oracle.  All rights reserved.
   4  */
   5
   6 #ifndef BTRFS_LOCKING_H
   7 #define BTRFS_LOCKING_H
   8
   9 #include "extent_io.h"
  10
  11 #define BTRFS_WRITE_LOCK 1
  12 #define BTRFS_READ_LOCK 2
  13 #define BTRFS_WRITE_LOCK_BLOCKING 3
  14 #define BTRFS_READ_LOCK_BLOCKING 4
  15
  16 void btrfs_tree_lock(struct extent_buffer *eb);
  17 void btrfs_tree_unlock(struct extent_buffer *eb);
  18
  19 void btrfs_tree_read_lock(struct extent_buffer *eb);
  20 void btrfs_tree_read_unlock(struct extent_buffer *eb);
  21 void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb);
  22 void btrfs_set_lock_blocking_read(struct extent_buffer *eb);
  23 void btrfs_set_lock_blocking_write(struct extent_buffer *eb);
  24 int btrfs_try_tree_read_lock(struct extent_buffer *eb);
  25 int btrfs_try_tree_write_lock(struct extent_buffer *eb);
  26 int btrfs_tree_read_lock_atomic(struct extent_buffer *eb);
  27
  28 #ifdef CONFIG_BTRFS_DEBUG
  29 static inline void btrfs_assert_tree_locked(struct extent_buffer *eb) {
  30         BUG_ON(!eb->write_locks);
  31 }
  32 #else
  33 static inline void btrfs_assert_tree_locked(struct extent_buffer *eb) { }
  34 #endif
  35
  36 void btrfs_set_path_blocking(struct btrfs_path *p);
  37 void btrfs_unlock_up_safe(struct btrfs_path *path, int level);
  38
  39 static inline void btrfs_tree_unlock_rw(struct extent_buffer *eb, int rw)
  40 {
  41         if (rw == BTRFS_WRITE_LOCK || rw == BTRFS_WRITE_LOCK_BLOCKING)
  42                 btrfs_tree_unlock(eb);
  43         else if (rw == BTRFS_READ_LOCK_BLOCKING)
  44                 btrfs_tree_read_unlock_blocking(eb);
  45         else if (rw == BTRFS_READ_LOCK)
  46                 btrfs_tree_read_unlock(eb);
  47         else
  48                 BUG();
  49 }
  50
  51 #endif