1 /* 2 * Copyright (C) 2008 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 19 #ifndef __BTRFS_LOCKING_ 20 #define __BTRFS_LOCKING_ 21 22 #define BTRFS_WRITE_LOCK 1 23 #define BTRFS_READ_LOCK 2 24 #define BTRFS_WRITE_LOCK_BLOCKING 3 25 #define BTRFS_READ_LOCK_BLOCKING 4 26 27 void btrfs_tree_lock(struct extent_buffer *eb); 28 void btrfs_tree_unlock(struct extent_buffer *eb); 29 int btrfs_try_spin_lock(struct extent_buffer *eb); 30 31 void btrfs_tree_read_lock(struct extent_buffer *eb); 32 void btrfs_tree_read_unlock(struct extent_buffer *eb); 33 void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb); 34 void btrfs_set_lock_blocking_rw(struct extent_buffer *eb, int rw); 35 void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw); 36 void btrfs_assert_tree_locked(struct extent_buffer *eb); 37 int btrfs_try_tree_read_lock(struct extent_buffer *eb); 38 int btrfs_try_tree_write_lock(struct extent_buffer *eb); 39 40 static inline void btrfs_tree_unlock_rw(struct extent_buffer *eb, int rw) 41 { 42 if (rw == BTRFS_WRITE_LOCK || rw == BTRFS_WRITE_LOCK_BLOCKING) 43 btrfs_tree_unlock(eb); 44 else if (rw == BTRFS_READ_LOCK_BLOCKING) 45 btrfs_tree_read_unlock_blocking(eb); 46 else if (rw == BTRFS_READ_LOCK) 47 btrfs_tree_read_unlock(eb); 48 else 49 BUG(); 50 } 51 52 static inline void btrfs_set_lock_blocking(struct extent_buffer *eb) 53 { 54 btrfs_set_lock_blocking_rw(eb, BTRFS_WRITE_LOCK); 55 } 56 57 static inline void btrfs_clear_lock_blocking(struct extent_buffer *eb) 58 { 59 btrfs_clear_lock_blocking_rw(eb, BTRFS_WRITE_LOCK_BLOCKING); 60 } 61 #endif 62