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_commit_super(struct btrfs_root *root); 64struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info, 65 u64 bytenr); 66struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root, 67 struct btrfs_key *location); 68int btrfs_init_fs_root(struct btrfs_root *root); 69int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, 70 struct btrfs_root *root); 71void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info); 72 73struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, 74 struct btrfs_key *key, 75 bool check_ref); 76static inline struct btrfs_root * 77btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info, 78 struct btrfs_key *location) 79{ 80 return btrfs_get_fs_root(fs_info, location, true); 81} 82 83int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info); 84void btrfs_btree_balance_dirty(struct btrfs_root *root); 85void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root); 86void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, 87 struct btrfs_root *root); 88void btrfs_free_fs_root(struct btrfs_root *root); 89 90#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 91struct btrfs_root *btrfs_alloc_dummy_root(void); 92#endif 93 94/* 95 * This function is used to grab the root, and avoid it is freed when we 96 * access it. But it doesn't ensure that the tree is not dropped. 97 * 98 * If you want to ensure the whole tree is safe, you should use 99 * fs_info->subvol_srcu 100 */ 101static inline struct btrfs_root *btrfs_grab_fs_root(struct btrfs_root *root) 102{ 103 if (atomic_inc_not_zero(&root->refs)) 104 return root; 105 return NULL; 106} 107 108static inline void btrfs_put_fs_root(struct btrfs_root *root) 109{ 110 if (atomic_dec_and_test(&root->refs)) 111 kfree(root); 112} 113 114void btrfs_mark_buffer_dirty(struct extent_buffer *buf); 115int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 116 int atomic); 117int btrfs_set_buffer_uptodate(struct extent_buffer *buf); 118int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid); 119u32 btrfs_csum_data(char *data, u32 seed, size_t len); 120void btrfs_csum_final(u32 crc, char *result); 121int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, 122 enum btrfs_wq_endio_type metadata); 123int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode, 124 int rw, struct bio *bio, int mirror_num, 125 unsigned long bio_flags, u64 bio_offset, 126 extent_submit_bio_hook_t *submit_bio_start, 127 extent_submit_bio_hook_t *submit_bio_done); 128unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info); 129int btrfs_write_tree_block(struct extent_buffer *buf); 130int btrfs_wait_tree_block_writeback(struct extent_buffer *buf); 131int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 132 struct btrfs_fs_info *fs_info); 133int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 134 struct btrfs_root *root); 135void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans, 136 struct btrfs_root *root); 137struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 138 struct btrfs_fs_info *fs_info, 139 u64 objectid); 140int btree_lock_page_hook(struct page *page, void *data, 141 void (*flush_fn)(void *)); 142int btrfs_calc_num_tolerated_disk_barrier_failures( 143 struct btrfs_fs_info *fs_info); 144int __init btrfs_end_io_wq_init(void); 145void btrfs_end_io_wq_exit(void); 146 147#ifdef CONFIG_DEBUG_LOCK_ALLOC 148void btrfs_init_lockdep(void); 149void btrfs_set_buffer_lockdep_class(u64 objectid, 150 struct extent_buffer *eb, int level); 151#else 152static inline void btrfs_init_lockdep(void) 153{ } 154static inline void btrfs_set_buffer_lockdep_class(u64 objectid, 155 struct extent_buffer *eb, int level) 156{ 157} 158#endif 159#endif 160