1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2007 Oracle. All rights reserved. 4 */ 5 6 #ifndef BTRFS_TRANSACTION_H 7 #define BTRFS_TRANSACTION_H 8 9 #include <linux/refcount.h> 10 #include "btrfs_inode.h" 11 #include "delayed-ref.h" 12 #include "ctree.h" 13 #include "misc.h" 14 15 /* Radix-tree tag for roots that are part of the trasaction. */ 16 #define BTRFS_ROOT_TRANS_TAG 0 17 18 enum btrfs_trans_state { 19 TRANS_STATE_RUNNING, 20 TRANS_STATE_COMMIT_PREP, 21 TRANS_STATE_COMMIT_START, 22 TRANS_STATE_COMMIT_DOING, 23 TRANS_STATE_UNBLOCKED, 24 TRANS_STATE_SUPER_COMMITTED, 25 TRANS_STATE_COMPLETED, 26 TRANS_STATE_MAX, 27 }; 28 29 #define BTRFS_TRANS_HAVE_FREE_BGS 0 30 #define BTRFS_TRANS_DIRTY_BG_RUN 1 31 #define BTRFS_TRANS_CACHE_ENOSPC 2 32 33 struct btrfs_transaction { 34 u64 transid; 35 /* 36 * total external writers(USERSPACE/START/ATTACH) in this 37 * transaction, it must be zero before the transaction is 38 * being committed 39 */ 40 atomic_t num_extwriters; 41 /* 42 * total writers in this transaction, it must be zero before the 43 * transaction can end 44 */ 45 atomic_t num_writers; 46 refcount_t use_count; 47 48 unsigned long flags; 49 50 /* Be protected by fs_info->trans_lock when we want to change it. */ 51 enum btrfs_trans_state state; 52 int aborted; 53 struct list_head list; 54 struct extent_io_tree dirty_pages; 55 time64_t start_time; 56 wait_queue_head_t writer_wait; 57 wait_queue_head_t commit_wait; 58 struct list_head pending_snapshots; 59 struct list_head dev_update_list; 60 struct list_head switch_commits; 61 struct list_head dirty_bgs; 62 63 /* 64 * There is no explicit lock which protects io_bgs, rather its 65 * consistency is implied by the fact that all the sites which modify 66 * it do so under some form of transaction critical section, namely: 67 * 68 * - btrfs_start_dirty_block_groups - This function can only ever be 69 * run by one of the transaction committers. Refer to 70 * BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction 71 * 72 * - btrfs_write_dirty_blockgroups - this is called by 73 * commit_cowonly_roots from transaction critical section 74 * (TRANS_STATE_COMMIT_DOING) 75 * 76 * - btrfs_cleanup_dirty_bgs - called on transaction abort 77 */ 78 struct list_head io_bgs; 79 struct list_head dropped_roots; 80 struct extent_io_tree pinned_extents; 81 82 /* 83 * we need to make sure block group deletion doesn't race with 84 * free space cache writeout. This mutex keeps them from stomping 85 * on each other 86 */ 87 struct mutex cache_write_mutex; 88 spinlock_t dirty_bgs_lock; 89 /* Protected by spin lock fs_info->unused_bgs_lock. */ 90 struct list_head deleted_bgs; 91 spinlock_t dropped_roots_lock; 92 struct btrfs_delayed_ref_root delayed_refs; 93 struct btrfs_fs_info *fs_info; 94 95 /* 96 * Number of ordered extents the transaction must wait for before 97 * committing. These are ordered extents started by a fast fsync. 98 */ 99 atomic_t pending_ordered; 100 wait_queue_head_t pending_wait; 101 }; 102 103 enum { 104 ENUM_BIT(__TRANS_FREEZABLE), 105 ENUM_BIT(__TRANS_START), 106 ENUM_BIT(__TRANS_ATTACH), 107 ENUM_BIT(__TRANS_JOIN), 108 ENUM_BIT(__TRANS_JOIN_NOLOCK), 109 ENUM_BIT(__TRANS_DUMMY), 110 ENUM_BIT(__TRANS_JOIN_NOSTART), 111 }; 112 113 #define TRANS_START (__TRANS_START | __TRANS_FREEZABLE) 114 #define TRANS_ATTACH (__TRANS_ATTACH) 115 #define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE) 116 #define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK) 117 #define TRANS_JOIN_NOSTART (__TRANS_JOIN_NOSTART) 118 119 #define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH) 120 121 struct btrfs_trans_handle { 122 u64 transid; 123 u64 bytes_reserved; 124 u64 chunk_bytes_reserved; 125 unsigned long delayed_ref_updates; 126 struct btrfs_transaction *transaction; 127 struct btrfs_block_rsv *block_rsv; 128 struct btrfs_block_rsv *orig_rsv; 129 /* Set by a task that wants to create a snapshot. */ 130 struct btrfs_pending_snapshot *pending_snapshot; 131 refcount_t use_count; 132 unsigned int type; 133 /* 134 * Error code of transaction abort, set outside of locks and must use 135 * the READ_ONCE/WRITE_ONCE access 136 */ 137 short aborted; 138 bool adding_csums; 139 bool allocating_chunk; 140 bool removing_chunk; 141 bool reloc_reserved; 142 bool in_fsync; 143 struct btrfs_fs_info *fs_info; 144 struct list_head new_bgs; 145 }; 146 147 /* 148 * The abort status can be changed between calls and is not protected by locks. 149 * This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's 150 * set to a non-zero value it does not change, so the macro should be in checks 151 * but is not necessary for further reads of the value. 152 */ 153 #define TRANS_ABORTED(trans) (unlikely(READ_ONCE((trans)->aborted))) 154 155 struct btrfs_pending_snapshot { 156 struct dentry *dentry; 157 struct inode *dir; 158 struct btrfs_root *root; 159 struct btrfs_root_item *root_item; 160 struct btrfs_root *snap; 161 struct btrfs_qgroup_inherit *inherit; 162 struct btrfs_path *path; 163 /* block reservation for the operation */ 164 struct btrfs_block_rsv block_rsv; 165 /* extra metadata reservation for relocation */ 166 int error; 167 /* Preallocated anonymous block device number */ 168 dev_t anon_dev; 169 bool readonly; 170 struct list_head list; 171 }; 172 173 static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans, 174 struct btrfs_inode *inode) 175 { 176 spin_lock(&inode->lock); 177 inode->last_trans = trans->transaction->transid; 178 inode->last_sub_trans = inode->root->log_transid; 179 inode->last_log_commit = inode->last_sub_trans - 1; 180 spin_unlock(&inode->lock); 181 } 182 183 /* 184 * Make qgroup codes to skip given qgroupid, means the old/new_roots for 185 * qgroup won't contain the qgroupid in it. 186 */ 187 static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans, 188 u64 qgroupid) 189 { 190 struct btrfs_delayed_ref_root *delayed_refs; 191 192 delayed_refs = &trans->transaction->delayed_refs; 193 WARN_ON(delayed_refs->qgroup_to_skip); 194 delayed_refs->qgroup_to_skip = qgroupid; 195 } 196 197 static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans) 198 { 199 struct btrfs_delayed_ref_root *delayed_refs; 200 201 delayed_refs = &trans->transaction->delayed_refs; 202 WARN_ON(!delayed_refs->qgroup_to_skip); 203 delayed_refs->qgroup_to_skip = 0; 204 } 205 206 bool __cold abort_should_print_stack(int errno); 207 208 /* 209 * Call btrfs_abort_transaction as early as possible when an error condition is 210 * detected, that way the exact stack trace is reported for some errors. 211 */ 212 #define btrfs_abort_transaction(trans, errno) \ 213 do { \ 214 bool first = false; \ 215 /* Report first abort since mount */ \ 216 if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED, \ 217 &((trans)->fs_info->fs_state))) { \ 218 first = true; \ 219 if (WARN(abort_should_print_stack(errno), \ 220 KERN_ERR \ 221 "BTRFS: Transaction aborted (error %d)\n", \ 222 (errno))) { \ 223 /* Stack trace printed. */ \ 224 } else { \ 225 btrfs_err((trans)->fs_info, \ 226 "Transaction aborted (error %d)", \ 227 (errno)); \ 228 } \ 229 } \ 230 __btrfs_abort_transaction((trans), __func__, \ 231 __LINE__, (errno), first); \ 232 } while (0) 233 234 int btrfs_end_transaction(struct btrfs_trans_handle *trans); 235 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, 236 unsigned int num_items); 237 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv( 238 struct btrfs_root *root, 239 unsigned int num_items); 240 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root); 241 struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root); 242 struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root); 243 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root); 244 struct btrfs_trans_handle *btrfs_attach_transaction_barrier( 245 struct btrfs_root *root); 246 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid); 247 248 void btrfs_add_dead_root(struct btrfs_root *root); 249 int btrfs_defrag_root(struct btrfs_root *root); 250 void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info); 251 int btrfs_clean_one_deleted_snapshot(struct btrfs_fs_info *fs_info); 252 int btrfs_commit_transaction(struct btrfs_trans_handle *trans); 253 void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans); 254 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans); 255 bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans); 256 void btrfs_throttle(struct btrfs_fs_info *fs_info); 257 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, 258 struct btrfs_root *root); 259 int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info, 260 struct extent_io_tree *dirty_pages, int mark); 261 int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark); 262 int btrfs_transaction_blocked(struct btrfs_fs_info *info); 263 int btrfs_transaction_in_commit(struct btrfs_fs_info *info); 264 void btrfs_put_transaction(struct btrfs_transaction *transaction); 265 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans, 266 struct btrfs_root *root); 267 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans); 268 void __cold __btrfs_abort_transaction(struct btrfs_trans_handle *trans, 269 const char *function, 270 unsigned int line, int errno, bool first_hit); 271 272 int __init btrfs_transaction_init(void); 273 void __cold btrfs_transaction_exit(void); 274 275 #endif 276