1/* 2 * Copyright (C) 2007 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 __DISKIO__ 20#define __DISKIO__ 21 22#define BTRFS_SUPER_INFO_OFFSET (64 * 1024) 23#define BTRFS_SUPER_INFO_SIZE 4096 24 25#define BTRFS_SUPER_MIRROR_MAX 3 26#define BTRFS_SUPER_MIRROR_SHIFT 12 27 28enum btrfs_wq_endio_type { 29 BTRFS_WQ_ENDIO_DATA = 0, 30 BTRFS_WQ_ENDIO_METADATA = 1, 31 BTRFS_WQ_ENDIO_FREE_SPACE = 2, 32 BTRFS_WQ_ENDIO_RAID56 = 3, 33 BTRFS_WQ_ENDIO_DIO_REPAIR = 4, 34}; 35 36static inline u64 btrfs_sb_offset(int mirror) 37{ 38 u64 start = 16 * 1024; 39 if (mirror) 40 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror); 41 return BTRFS_SUPER_INFO_OFFSET; 42} 43 44struct btrfs_device; 45struct btrfs_fs_devices; 46 47struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr, 48 u64 parent_transid); 49void readahead_tree_block(struct btrfs_root *root, u64 bytenr); 50int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, 51 int mirror_num, struct extent_buffer **eb); 52struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root, 53 u64 bytenr); 54void clean_tree_block(struct btrfs_trans_handle *trans, 55 struct btrfs_fs_info *fs_info, struct extent_buffer *buf); 56int open_ctree(struct super_block *sb, 57 struct btrfs_fs_devices *fs_devices, 58 char *options); 59void close_ctree(struct btrfs_root *root); 60int write_ctree_super(struct btrfs_trans_handle *trans, 61 struct btrfs_root *root, int max_mirrors); 62struct buffer_head *btrfs_read_dev_super(struct block_device *bdev); 63int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, 64 struct buffer_head **bh_ret); 65int btrfs_commit_super(struct btrfs_root *root); 66struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info, 67 u64 bytenr); 68struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root, 69 struct btrfs_key *location); 70int btrfs_init_fs_root(struct btrfs_root *root); 71int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, 72 struct btrfs_root *root); 73void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info); 74 75struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, 76 struct btrfs_key *key, 77 bool check_ref); 78static inline struct btrfs_root * 79btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info, 80 struct btrfs_key *location) 81{ 82 return btrfs_get_fs_root(fs_info, location, true); 83} 84 85int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info); 86void btrfs_btree_balance_dirty(struct btrfs_root *root); 87void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root); 88void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, 89 struct btrfs_root *root); 90void btrfs_free_fs_root(struct btrfs_root *root); 91 92#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 93struct btrfs_root *btrfs_alloc_dummy_root(void); 94#endif 95 96/* 97 * This function is used to grab the root, and avoid it is freed when we 98 * access it. But it doesn't ensure that the tree is not dropped. 99 * 100 * If you want to ensure the whole tree is safe, you should use 101 * fs_info->subvol_srcu 102 */ 103static inline struct btrfs_root *btrfs_grab_fs_root(struct btrfs_root *root) 104{ 105 if (atomic_inc_not_zero(&root->refs)) 106 return root; 107 return NULL; 108} 109 110static inline void btrfs_put_fs_root(struct btrfs_root *root) 111{ 112 if (atomic_dec_and_test(&root->refs)) 113 kfree(root); 114} 115 116void btrfs_mark_buffer_dirty(struct extent_buffer *buf); 117int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 118 int atomic); 119int btrfs_set_buffer_uptodate(struct extent_buffer *buf); 120int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid); 121u32 btrfs_csum_data(char *data, u32 seed, size_t len); 122void btrfs_csum_final(u32 crc, char *result); 123int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, 124 enum btrfs_wq_endio_type metadata); 125int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode, 126 int rw, struct bio *bio, int mirror_num, 127 unsigned long bio_flags, u64 bio_offset, 128 extent_submit_bio_hook_t *submit_bio_start, 129 extent_submit_bio_hook_t *submit_bio_done); 130unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info); 131int btrfs_write_tree_block(struct extent_buffer *buf); 132int btrfs_wait_tree_block_writeback(struct extent_buffer *buf); 133int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 134 struct btrfs_fs_info *fs_info); 135int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 136 struct btrfs_root *root); 137void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans, 138 struct btrfs_root *root); 139struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 140 struct btrfs_fs_info *fs_info, 141 u64 objectid); 142int btree_lock_page_hook(struct page *page, void *data, 143 void (*flush_fn)(void *)); 144int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags); 145int btrfs_calc_num_tolerated_disk_barrier_failures( 146 struct btrfs_fs_info *fs_info); 147int __init btrfs_end_io_wq_init(void); 148void btrfs_end_io_wq_exit(void); 149 150#ifdef CONFIG_DEBUG_LOCK_ALLOC 151void btrfs_init_lockdep(void); 152void btrfs_set_buffer_lockdep_class(u64 objectid, 153 struct extent_buffer *eb, int level); 154#else 155static inline void btrfs_init_lockdep(void) 156{ } 157static inline void btrfs_set_buffer_lockdep_class(u64 objectid, 158 struct extent_buffer *eb, int level) 159{ 160} 161#endif 162#endif 163