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_SUPER_COMMITTED, 20 TRANS_STATE_COMPLETED, 21 TRANS_STATE_MAX, 22 }; 23 24 #define BTRFS_TRANS_HAVE_FREE_BGS 0 25 #define BTRFS_TRANS_DIRTY_BG_RUN 1 26 #define BTRFS_TRANS_CACHE_ENOSPC 2 27 28 struct btrfs_transaction { 29 u64 transid; 30 /* 31 * total external writers(USERSPACE/START/ATTACH) in this 32 * transaction, it must be zero before the transaction is 33 * being committed 34 */ 35 atomic_t num_extwriters; 36 /* 37 * total writers in this transaction, it must be zero before the 38 * transaction can end 39 */ 40 atomic_t num_writers; 41 refcount_t use_count; 42 43 unsigned long flags; 44 45 /* Be protected by fs_info->trans_lock when we want to change it. */ 46 enum btrfs_trans_state state; 47 int aborted; 48 struct list_head list; 49 struct extent_io_tree dirty_pages; 50 time64_t start_time; 51 wait_queue_head_t writer_wait; 52 wait_queue_head_t commit_wait; 53 struct list_head pending_snapshots; 54 struct list_head dev_update_list; 55 struct list_head switch_commits; 56 struct list_head dirty_bgs; 57 58 /* 59 * There is no explicit lock which protects io_bgs, rather its 60 * consistency is implied by the fact that all the sites which modify 61 * it do so under some form of transaction critical section, namely: 62 * 63 * - btrfs_start_dirty_block_groups - This function can only ever be 64 * run by one of the transaction committers. Refer to 65 * BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction 66 * 67 * - btrfs_write_dirty_blockgroups - this is called by 68 * commit_cowonly_roots from transaction critical section 69 * (TRANS_STATE_COMMIT_DOING) 70 * 71 * - btrfs_cleanup_dirty_bgs - called on transaction abort 72 */ 73 struct list_head io_bgs; 74 struct list_head dropped_roots; 75 struct extent_io_tree pinned_extents; 76 77 /* 78 * we need to make sure block group deletion doesn't race with 79 * free space cache writeout. This mutex keeps them from stomping 80 * on each other 81 */ 82 struct mutex cache_write_mutex; 83 spinlock_t dirty_bgs_lock; 84 /* Protected by spin lock fs_info->unused_bgs_lock. */ 85 struct list_head deleted_bgs; 86 spinlock_t dropped_roots_lock; 87 struct btrfs_delayed_ref_root delayed_refs; 88 struct btrfs_fs_info *fs_info; 89 90 /* 91 * Number of ordered extents the transaction must wait for before 92 * committing. These are ordered extents started by a fast fsync. 93 */ 94 atomic_t pending_ordered; 95 wait_queue_head_t pending_wait; 96 97 spinlock_t releasing_ebs_lock; 98 struct list_head releasing_ebs; 99 }; 100 101 #define __TRANS_FREEZABLE (1U << 0) 102 103 #define __TRANS_START (1U << 9) 104 #define __TRANS_ATTACH (1U << 10) 105 #define __TRANS_JOIN (1U << 11) 106 #define __TRANS_JOIN_NOLOCK (1U << 12) 107 #define __TRANS_DUMMY (1U << 13) 108 #define __TRANS_JOIN_NOSTART (1U << 14) 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 int btrfs_end_transaction(struct btrfs_trans_handle *trans); 204 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, 205 unsigned int num_items); 206 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv( 207 struct btrfs_root *root, 208 unsigned int num_items); 209 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root); 210 struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root); 211 struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root); 212 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root); 213 struct btrfs_trans_handle *btrfs_attach_transaction_barrier( 214 struct btrfs_root *root); 215 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid); 216 217 void btrfs_add_dead_root(struct btrfs_root *root); 218 int btrfs_defrag_root(struct btrfs_root *root); 219 void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info); 220 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root); 221 int btrfs_commit_transaction(struct btrfs_trans_handle *trans); 222 void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans); 223 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans); 224 bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans); 225 void btrfs_throttle(struct btrfs_fs_info *fs_info); 226 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, 227 struct btrfs_root *root); 228 int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info, 229 struct extent_io_tree *dirty_pages, int mark); 230 int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark); 231 int btrfs_transaction_blocked(struct btrfs_fs_info *info); 232 int btrfs_transaction_in_commit(struct btrfs_fs_info *info); 233 void btrfs_put_transaction(struct btrfs_transaction *transaction); 234 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info); 235 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans, 236 struct btrfs_root *root); 237 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans); 238 239 #endif 240