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 SZ_64K 23 #define BTRFS_SUPER_INFO_SIZE 4096 24 25 #define BTRFS_SUPER_MIRROR_MAX 3 26 #define BTRFS_SUPER_MIRROR_SHIFT 12 27 28 /* 29 * Fixed blocksize for all devices, applies to specific ways of reading 30 * metadata like superblock. Must meet the set_blocksize requirements. 31 * 32 * Do not change. 33 */ 34 #define BTRFS_BDEV_BLOCKSIZE (4096) 35 36 enum btrfs_wq_endio_type { 37 BTRFS_WQ_ENDIO_DATA = 0, 38 BTRFS_WQ_ENDIO_METADATA = 1, 39 BTRFS_WQ_ENDIO_FREE_SPACE = 2, 40 BTRFS_WQ_ENDIO_RAID56 = 3, 41 BTRFS_WQ_ENDIO_DIO_REPAIR = 4, 42 }; 43 44 static inline u64 btrfs_sb_offset(int mirror) 45 { 46 u64 start = SZ_16K; 47 if (mirror) 48 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror); 49 return BTRFS_SUPER_INFO_OFFSET; 50 } 51 52 struct btrfs_device; 53 struct btrfs_fs_devices; 54 55 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr, 56 u64 parent_transid, int level, 57 struct btrfs_key *first_key); 58 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr); 59 int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr, 60 int mirror_num, struct extent_buffer **eb); 61 struct extent_buffer *btrfs_find_create_tree_block( 62 struct btrfs_fs_info *fs_info, 63 u64 bytenr); 64 void clean_tree_block(struct btrfs_fs_info *fs_info, struct extent_buffer *buf); 65 int open_ctree(struct super_block *sb, 66 struct btrfs_fs_devices *fs_devices, 67 char *options); 68 void close_ctree(struct btrfs_fs_info *fs_info); 69 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors); 70 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev); 71 int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, 72 struct buffer_head **bh_ret); 73 int btrfs_commit_super(struct btrfs_fs_info *fs_info); 74 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root, 75 struct btrfs_key *location); 76 int btrfs_init_fs_root(struct btrfs_root *root); 77 struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info, 78 u64 root_id); 79 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, 80 struct btrfs_root *root); 81 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info); 82 83 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, 84 struct btrfs_key *key, 85 bool check_ref); 86 static inline struct btrfs_root * 87 btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info, 88 struct btrfs_key *location) 89 { 90 return btrfs_get_fs_root(fs_info, location, true); 91 } 92 93 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info); 94 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info); 95 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info); 96 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, 97 struct btrfs_root *root); 98 void btrfs_free_fs_root(struct btrfs_root *root); 99 100 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 101 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info); 102 #endif 103 104 /* 105 * This function is used to grab the root, and avoid it is freed when we 106 * access it. But it doesn't ensure that the tree is not dropped. 107 * 108 * If you want to ensure the whole tree is safe, you should use 109 * fs_info->subvol_srcu 110 */ 111 static inline struct btrfs_root *btrfs_grab_fs_root(struct btrfs_root *root) 112 { 113 if (refcount_inc_not_zero(&root->refs)) 114 return root; 115 return NULL; 116 } 117 118 static inline void btrfs_put_fs_root(struct btrfs_root *root) 119 { 120 if (refcount_dec_and_test(&root->refs)) 121 kfree(root); 122 } 123 124 void btrfs_mark_buffer_dirty(struct extent_buffer *buf); 125 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 126 int atomic); 127 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level, 128 struct btrfs_key *first_key); 129 u32 btrfs_csum_data(const char *data, u32 seed, size_t len); 130 void btrfs_csum_final(u32 crc, u8 *result); 131 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, 132 enum btrfs_wq_endio_type metadata); 133 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio, 134 int mirror_num, unsigned long bio_flags, 135 u64 bio_offset, void *private_data, 136 extent_submit_bio_start_t *submit_bio_start, 137 extent_submit_bio_done_t *submit_bio_done); 138 int btrfs_write_tree_block(struct extent_buffer *buf); 139 void btrfs_wait_tree_block_writeback(struct extent_buffer *buf); 140 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 141 struct btrfs_fs_info *fs_info); 142 int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 143 struct btrfs_root *root); 144 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans, 145 struct btrfs_fs_info *fs_info); 146 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans, 147 struct btrfs_fs_info *fs_info); 148 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 149 struct btrfs_fs_info *fs_info, 150 u64 objectid); 151 int btree_lock_page_hook(struct page *page, void *data, 152 void (*flush_fn)(void *)); 153 struct extent_map *btree_get_extent(struct btrfs_inode *inode, 154 struct page *page, size_t pg_offset, u64 start, u64 len, 155 int create); 156 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags); 157 int __init btrfs_end_io_wq_init(void); 158 void __cold btrfs_end_io_wq_exit(void); 159 160 #ifdef CONFIG_DEBUG_LOCK_ALLOC 161 void btrfs_init_lockdep(void); 162 void btrfs_set_buffer_lockdep_class(u64 objectid, 163 struct extent_buffer *eb, int level); 164 #else 165 static inline void btrfs_init_lockdep(void) 166 { } 167 static inline void btrfs_set_buffer_lockdep_class(u64 objectid, 168 struct extent_buffer *eb, int level) 169 { 170 } 171 #endif 172 #endif 173