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 14 enum btrfs_trans_state { 15 TRANS_STATE_RUNNING, 16 TRANS_STATE_COMMIT_START, 17 TRANS_STATE_COMMIT_DOING, 18 TRANS_STATE_UNBLOCKED, 19 TRANS_STATE_COMPLETED, 20 TRANS_STATE_MAX, 21 }; 22 23 #define BTRFS_TRANS_HAVE_FREE_BGS 0 24 #define BTRFS_TRANS_DIRTY_BG_RUN 1 25 #define BTRFS_TRANS_CACHE_ENOSPC 2 26 27 struct btrfs_transaction { 28 u64 transid; 29 /* 30 * total external writers(USERSPACE/START/ATTACH) in this 31 * transaction, it must be zero before the transaction is 32 * being committed 33 */ 34 atomic_t num_extwriters; 35 /* 36 * total writers in this transaction, it must be zero before the 37 * transaction can end 38 */ 39 atomic_t num_writers; 40 refcount_t use_count; 41 42 unsigned long flags; 43 44 /* Be protected by fs_info->trans_lock when we want to change it. */ 45 enum btrfs_trans_state state; 46 int aborted; 47 struct list_head list; 48 struct extent_io_tree dirty_pages; 49 time64_t start_time; 50 wait_queue_head_t writer_wait; 51 wait_queue_head_t commit_wait; 52 struct list_head pending_snapshots; 53 struct list_head dev_update_list; 54 struct list_head switch_commits; 55 struct list_head dirty_bgs; 56 57 /* 58 * There is no explicit lock which protects io_bgs, rather its 59 * consistency is implied by the fact that all the sites which modify 60 * it do so under some form of transaction critical section, namely: 61 * 62 * - btrfs_start_dirty_block_groups - This function can only ever be 63 * run by one of the transaction committers. Refer to 64 * BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction 65 * 66 * - btrfs_write_dirty_blockgroups - this is called by 67 * commit_cowonly_roots from transaction critical section 68 * (TRANS_STATE_COMMIT_DOING) 69 * 70 * - btrfs_cleanup_dirty_bgs - called on transaction abort 71 */ 72 struct list_head io_bgs; 73 struct list_head dropped_roots; 74 struct extent_io_tree pinned_extents; 75 76 /* 77 * we need to make sure block group deletion doesn't race with 78 * free space cache writeout. This mutex keeps them from stomping 79 * on each other 80 */ 81 struct mutex cache_write_mutex; 82 spinlock_t dirty_bgs_lock; 83 /* Protected by spin lock fs_info->unused_bgs_lock. */ 84 struct list_head deleted_bgs; 85 spinlock_t dropped_roots_lock; 86 struct btrfs_delayed_ref_root delayed_refs; 87 struct btrfs_fs_info *fs_info; 88 }; 89 90 #define __TRANS_FREEZABLE (1U << 0) 91 92 #define __TRANS_START (1U << 9) 93 #define __TRANS_ATTACH (1U << 10) 94 #define __TRANS_JOIN (1U << 11) 95 #define __TRANS_JOIN_NOLOCK (1U << 12) 96 #define __TRANS_DUMMY (1U << 13) 97 #define __TRANS_JOIN_NOSTART (1U << 14) 98 99 #define TRANS_START (__TRANS_START | __TRANS_FREEZABLE) 100 #define TRANS_ATTACH (__TRANS_ATTACH) 101 #define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE) 102 #define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK) 103 #define TRANS_JOIN_NOSTART (__TRANS_JOIN_NOSTART) 104 105 #define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH) 106 107 #define BTRFS_SEND_TRANS_STUB ((void *)1) 108 109 struct btrfs_trans_handle { 110 u64 transid; 111 u64 bytes_reserved; 112 u64 chunk_bytes_reserved; 113 unsigned long delayed_ref_updates; 114 struct btrfs_transaction *transaction; 115 struct btrfs_block_rsv *block_rsv; 116 struct btrfs_block_rsv *orig_rsv; 117 refcount_t use_count; 118 unsigned int type; 119 /* 120 * Error code of transaction abort, set outside of locks and must use 121 * the READ_ONCE/WRITE_ONCE access 122 */ 123 short aborted; 124 bool adding_csums; 125 bool allocating_chunk; 126 bool can_flush_pending_bgs; 127 bool reloc_reserved; 128 bool dirty; 129 struct btrfs_root *root; 130 struct btrfs_fs_info *fs_info; 131 struct list_head new_bgs; 132 }; 133 134 /* 135 * The abort status can be changed between calls and is not protected by locks. 136 * This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's 137 * set to a non-zero value it does not change, so the macro should be in checks 138 * but is not necessary for further reads of the value. 139 */ 140 #define TRANS_ABORTED(trans) (unlikely(READ_ONCE((trans)->aborted))) 141 142 struct btrfs_pending_snapshot { 143 struct dentry *dentry; 144 struct inode *dir; 145 struct btrfs_root *root; 146 struct btrfs_root_item *root_item; 147 struct btrfs_root *snap; 148 struct btrfs_qgroup_inherit *inherit; 149 struct btrfs_path *path; 150 /* block reservation for the operation */ 151 struct btrfs_block_rsv block_rsv; 152 /* extra metadata reservation for relocation */ 153 int error; 154 bool readonly; 155 struct list_head list; 156 }; 157 158 static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans, 159 struct inode *inode) 160 { 161 spin_lock(&BTRFS_I(inode)->lock); 162 BTRFS_I(inode)->last_trans = trans->transaction->transid; 163 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid; 164 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit; 165 spin_unlock(&BTRFS_I(inode)->lock); 166 } 167 168 /* 169 * Make qgroup codes to skip given qgroupid, means the old/new_roots for 170 * qgroup won't contain the qgroupid in it. 171 */ 172 static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans, 173 u64 qgroupid) 174 { 175 struct btrfs_delayed_ref_root *delayed_refs; 176 177 delayed_refs = &trans->transaction->delayed_refs; 178 WARN_ON(delayed_refs->qgroup_to_skip); 179 delayed_refs->qgroup_to_skip = qgroupid; 180 } 181 182 static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans) 183 { 184 struct btrfs_delayed_ref_root *delayed_refs; 185 186 delayed_refs = &trans->transaction->delayed_refs; 187 WARN_ON(!delayed_refs->qgroup_to_skip); 188 delayed_refs->qgroup_to_skip = 0; 189 } 190 191 int btrfs_end_transaction(struct btrfs_trans_handle *trans); 192 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, 193 unsigned int num_items); 194 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv( 195 struct btrfs_root *root, 196 unsigned int num_items, 197 int min_factor); 198 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root); 199 struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root); 200 struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root); 201 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root); 202 struct btrfs_trans_handle *btrfs_attach_transaction_barrier( 203 struct btrfs_root *root); 204 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid); 205 206 void btrfs_add_dead_root(struct btrfs_root *root); 207 int btrfs_defrag_root(struct btrfs_root *root); 208 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root); 209 int btrfs_commit_transaction(struct btrfs_trans_handle *trans); 210 int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans, 211 int wait_for_unblock); 212 213 /* 214 * Try to commit transaction asynchronously, so this is safe to call 215 * even holding a spinlock. 216 * 217 * It's done by informing transaction_kthread to commit transaction without 218 * waiting for commit interval. 219 */ 220 static inline void btrfs_commit_transaction_locksafe( 221 struct btrfs_fs_info *fs_info) 222 { 223 set_bit(BTRFS_FS_NEED_ASYNC_COMMIT, &fs_info->flags); 224 wake_up_process(fs_info->transaction_kthread); 225 } 226 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans); 227 int btrfs_should_end_transaction(struct btrfs_trans_handle *trans); 228 void btrfs_throttle(struct btrfs_fs_info *fs_info); 229 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, 230 struct btrfs_root *root); 231 int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info, 232 struct extent_io_tree *dirty_pages, int mark); 233 int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark); 234 int btrfs_transaction_blocked(struct btrfs_fs_info *info); 235 int btrfs_transaction_in_commit(struct btrfs_fs_info *info); 236 void btrfs_put_transaction(struct btrfs_transaction *transaction); 237 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info); 238 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans, 239 struct btrfs_root *root); 240 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans); 241 242 #endif 243