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, 56 u64 bytenr, u64 parent_transid); 57 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr); 58 int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr, 59 int mirror_num, struct extent_buffer **eb); 60 struct extent_buffer *btrfs_find_create_tree_block( 61 struct btrfs_fs_info *fs_info, 62 u64 bytenr); 63 void clean_tree_block(struct btrfs_fs_info *fs_info, struct extent_buffer *buf); 64 int open_ctree(struct super_block *sb, 65 struct btrfs_fs_devices *fs_devices, 66 char *options); 67 void close_ctree(struct btrfs_fs_info *fs_info); 68 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors); 69 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev); 70 int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, 71 struct buffer_head **bh_ret); 72 int btrfs_commit_super(struct btrfs_fs_info *fs_info); 73 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root, 74 struct btrfs_key *location); 75 int btrfs_init_fs_root(struct btrfs_root *root); 76 struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info, 77 u64 root_id); 78 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, 79 struct btrfs_root *root); 80 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info); 81 82 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, 83 struct btrfs_key *key, 84 bool check_ref); 85 static inline struct btrfs_root * 86 btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info, 87 struct btrfs_key *location) 88 { 89 return btrfs_get_fs_root(fs_info, location, true); 90 } 91 92 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info); 93 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info); 94 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info); 95 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, 96 struct btrfs_root *root); 97 void btrfs_free_fs_root(struct btrfs_root *root); 98 99 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 100 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info); 101 #endif 102 103 /* 104 * This function is used to grab the root, and avoid it is freed when we 105 * access it. But it doesn't ensure that the tree is not dropped. 106 * 107 * If you want to ensure the whole tree is safe, you should use 108 * fs_info->subvol_srcu 109 */ 110 static inline struct btrfs_root *btrfs_grab_fs_root(struct btrfs_root *root) 111 { 112 if (refcount_inc_not_zero(&root->refs)) 113 return root; 114 return NULL; 115 } 116 117 static inline void btrfs_put_fs_root(struct btrfs_root *root) 118 { 119 if (refcount_dec_and_test(&root->refs)) 120 kfree(root); 121 } 122 123 void btrfs_mark_buffer_dirty(struct extent_buffer *buf); 124 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 125 int atomic); 126 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid); 127 u32 btrfs_csum_data(const char *data, u32 seed, size_t len); 128 void btrfs_csum_final(u32 crc, u8 *result); 129 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, 130 enum btrfs_wq_endio_type metadata); 131 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio, 132 int mirror_num, unsigned long bio_flags, 133 u64 bio_offset, void *private_data, 134 extent_submit_bio_hook_t *submit_bio_start, 135 extent_submit_bio_hook_t *submit_bio_done); 136 unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info); 137 int btrfs_write_tree_block(struct extent_buffer *buf); 138 void btrfs_wait_tree_block_writeback(struct extent_buffer *buf); 139 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 140 struct btrfs_fs_info *fs_info); 141 int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 142 struct btrfs_root *root); 143 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans, 144 struct btrfs_fs_info *fs_info); 145 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans, 146 struct btrfs_fs_info *fs_info); 147 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 148 struct btrfs_fs_info *fs_info, 149 u64 objectid); 150 int btree_lock_page_hook(struct page *page, void *data, 151 void (*flush_fn)(void *)); 152 struct extent_map *btree_get_extent(struct btrfs_inode *inode, 153 struct page *page, size_t pg_offset, u64 start, u64 len, 154 int create); 155 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags); 156 int __init btrfs_end_io_wq_init(void); 157 void btrfs_end_io_wq_exit(void); 158 159 #ifdef CONFIG_DEBUG_LOCK_ALLOC 160 void btrfs_init_lockdep(void); 161 void btrfs_set_buffer_lockdep_class(u64 objectid, 162 struct extent_buffer *eb, int level); 163 #else 164 static inline void btrfs_init_lockdep(void) 165 { } 166 static inline void btrfs_set_buffer_lockdep_class(u64 objectid, 167 struct extent_buffer *eb, int level) 168 { 169 } 170 #endif 171 #endif 172