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 enum 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 36 static inline u64 btrfs_sb_offset(int mirror) 37 { 38 u64 start = SZ_16K; 39 if (mirror) 40 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror); 41 return BTRFS_SUPER_INFO_OFFSET; 42 } 43 44 struct btrfs_device; 45 struct btrfs_fs_devices; 46 47 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr, 48 u64 parent_transid); 49 void readahead_tree_block(struct btrfs_root *root, u64 bytenr); 50 int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, 51 int mirror_num, struct extent_buffer **eb); 52 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root, 53 u64 bytenr); 54 void clean_tree_block(struct btrfs_trans_handle *trans, 55 struct btrfs_fs_info *fs_info, struct extent_buffer *buf); 56 int open_ctree(struct super_block *sb, 57 struct btrfs_fs_devices *fs_devices, 58 char *options); 59 void close_ctree(struct btrfs_root *root); 60 int write_ctree_super(struct btrfs_trans_handle *trans, 61 struct btrfs_root *root, int max_mirrors); 62 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev); 63 int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, 64 struct buffer_head **bh_ret); 65 int btrfs_commit_super(struct btrfs_root *root); 66 struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info, 67 u64 bytenr); 68 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root, 69 struct btrfs_key *location); 70 int btrfs_init_fs_root(struct btrfs_root *root); 71 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, 72 struct btrfs_root *root); 73 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info); 74 75 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, 76 struct btrfs_key *key, 77 bool check_ref); 78 static inline struct btrfs_root * 79 btrfs_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 85 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info); 86 void btrfs_btree_balance_dirty(struct btrfs_root *root); 87 void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root); 88 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, 89 struct btrfs_root *root); 90 void btrfs_free_fs_root(struct btrfs_root *root); 91 92 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 93 struct btrfs_root *btrfs_alloc_dummy_root(u32 sectorsize, u32 nodesize); 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 */ 103 static 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 } 109 110 static inline void btrfs_put_fs_root(struct btrfs_root *root) 111 { 112 if (atomic_dec_and_test(&root->refs)) 113 kfree(root); 114 } 115 116 void btrfs_mark_buffer_dirty(struct extent_buffer *buf); 117 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 118 int atomic); 119 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid); 120 u32 btrfs_csum_data(char *data, u32 seed, size_t len); 121 void btrfs_csum_final(u32 crc, char *result); 122 int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, 123 enum btrfs_wq_endio_type metadata); 124 int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode, 125 struct bio *bio, int mirror_num, 126 unsigned long bio_flags, u64 bio_offset, 127 extent_submit_bio_hook_t *submit_bio_start, 128 extent_submit_bio_hook_t *submit_bio_done); 129 unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info); 130 int btrfs_write_tree_block(struct extent_buffer *buf); 131 int btrfs_wait_tree_block_writeback(struct extent_buffer *buf); 132 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 133 struct btrfs_fs_info *fs_info); 134 int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 135 struct btrfs_root *root); 136 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans, 137 struct btrfs_root *root); 138 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 139 struct btrfs_fs_info *fs_info, 140 u64 objectid); 141 int btree_lock_page_hook(struct page *page, void *data, 142 void (*flush_fn)(void *)); 143 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags); 144 int btrfs_calc_num_tolerated_disk_barrier_failures( 145 struct btrfs_fs_info *fs_info); 146 int __init btrfs_end_io_wq_init(void); 147 void btrfs_end_io_wq_exit(void); 148 149 #ifdef CONFIG_DEBUG_LOCK_ALLOC 150 void btrfs_init_lockdep(void); 151 void btrfs_set_buffer_lockdep_class(u64 objectid, 152 struct extent_buffer *eb, int level); 153 #else 154 static inline void btrfs_init_lockdep(void) 155 { } 156 static inline void btrfs_set_buffer_lockdep_class(u64 objectid, 157 struct extent_buffer *eb, int level) 158 { 159 } 160 #endif 161 #endif 162