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 28 enum { 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 }; 34 35 static inline u64 btrfs_sb_offset(int mirror) 36 { 37 u64 start = 16 * 1024; 38 if (mirror) 39 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror); 40 return BTRFS_SUPER_INFO_OFFSET; 41 } 42 43 struct btrfs_device; 44 struct btrfs_fs_devices; 45 46 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr, 47 u32 blocksize, u64 parent_transid); 48 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize, 49 u64 parent_transid); 50 int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize, 51 int mirror_num, struct extent_buffer **eb); 52 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root, 53 u64 bytenr, u32 blocksize); 54 void clean_tree_block(struct btrfs_trans_handle *trans, 55 struct btrfs_root *root, struct extent_buffer *buf); 56 int open_ctree(struct super_block *sb, 57 struct btrfs_fs_devices *fs_devices, 58 char *options); 59 int 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_commit_super(struct btrfs_root *root); 64 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root, 65 u64 bytenr, u32 blocksize); 66 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root, 67 struct btrfs_key *location); 68 int btrfs_init_fs_root(struct btrfs_root *root); 69 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, 70 struct btrfs_root *root); 71 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info); 72 73 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, 74 struct btrfs_key *key, 75 bool check_ref); 76 static inline struct btrfs_root * 77 btrfs_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 83 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info); 84 void btrfs_btree_balance_dirty(struct btrfs_root *root); 85 void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root); 86 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, 87 struct btrfs_root *root); 88 void btrfs_free_fs_root(struct btrfs_root *root); 89 90 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 91 struct 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 */ 101 static 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 } 107 108 static inline void btrfs_put_fs_root(struct btrfs_root *root) 109 { 110 if (atomic_dec_and_test(&root->refs)) 111 kfree(root); 112 } 113 114 void btrfs_mark_buffer_dirty(struct extent_buffer *buf); 115 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 116 int atomic); 117 int btrfs_set_buffer_uptodate(struct extent_buffer *buf); 118 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid); 119 u32 btrfs_csum_data(char *data, u32 seed, size_t len); 120 void btrfs_csum_final(u32 crc, char *result); 121 int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, 122 int metadata); 123 int 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); 128 unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info); 129 int btrfs_write_tree_block(struct extent_buffer *buf); 130 int btrfs_wait_tree_block_writeback(struct extent_buffer *buf); 131 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 132 struct btrfs_fs_info *fs_info); 133 int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 134 struct btrfs_root *root); 135 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans, 136 struct btrfs_root *root); 137 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 138 struct btrfs_fs_info *fs_info, 139 u64 objectid); 140 int btree_lock_page_hook(struct page *page, void *data, 141 void (*flush_fn)(void *)); 142 int btrfs_calc_num_tolerated_disk_barrier_failures( 143 struct btrfs_fs_info *fs_info); 144 145 #ifdef CONFIG_DEBUG_LOCK_ALLOC 146 void btrfs_init_lockdep(void); 147 void btrfs_set_buffer_lockdep_class(u64 objectid, 148 struct extent_buffer *eb, int level); 149 #else 150 static inline void btrfs_init_lockdep(void) 151 { } 152 static inline void btrfs_set_buffer_lockdep_class(u64 objectid, 153 struct extent_buffer *eb, int level) 154 { 155 } 156 #endif 157 #endif 158