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