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 #define BTRFS_WRITE_LOCK 1
  10 #define BTRFS_READ_LOCK 2
  11 #define BTRFS_WRITE_LOCK_BLOCKING 3
  12 #define BTRFS_READ_LOCK_BLOCKING 4
  13
  14 void btrfs_tree_lock(struct extent_buffer *eb);
  15 void btrfs_tree_unlock(struct extent_buffer *eb);
  16
  17 void btrfs_tree_read_lock(struct extent_buffer *eb);
  18 void btrfs_tree_read_unlock(struct extent_buffer *eb);
  19 void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb);
  20 void btrfs_set_lock_blocking_rw(struct extent_buffer *eb, int rw);
  21 void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw);
  22 void btrfs_assert_tree_locked(struct extent_buffer *eb);
  23 int btrfs_try_tree_read_lock(struct extent_buffer *eb);
  24 int btrfs_try_tree_write_lock(struct extent_buffer *eb);
  25 int btrfs_tree_read_lock_atomic(struct extent_buffer *eb);
  26
  27
  28 static inline void btrfs_tree_unlock_rw(struct extent_buffer *eb, int rw)
  29 {
  30         if (rw == BTRFS_WRITE_LOCK || rw == BTRFS_WRITE_LOCK_BLOCKING)
  31                 btrfs_tree_unlock(eb);
  32         else if (rw == BTRFS_READ_LOCK_BLOCKING)
  33                 btrfs_tree_read_unlock_blocking(eb);
  34         else if (rw == BTRFS_READ_LOCK)
  35                 btrfs_tree_read_unlock(eb);
  36         else
  37                 BUG();
  38 }
  39
  40 static inline void btrfs_set_lock_blocking(struct extent_buffer *eb)
  41 {
  42         btrfs_set_lock_blocking_rw(eb, BTRFS_WRITE_LOCK);
  43 }
  44
  45 static inline void btrfs_clear_lock_blocking(struct extent_buffer *eb)
  46 {
  47         btrfs_clear_lock_blocking_rw(eb, BTRFS_WRITE_LOCK_BLOCKING);
  48 }
  49 #endif