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/atomic.h> 10#include <linux/refcount.h> 11#include <linux/list.h> 12#include <linux/time64.h> 13#include <linux/mutex.h> 14#include <linux/wait.h> 15#include "btrfs_inode.h" 16#include "delayed-ref.h" 17#include "extent-io-tree.h" 18#include "block-rsv.h" 19#include "messages.h" 20#include "misc.h" 21 22struct dentry; 23struct inode; 24struct btrfs_pending_snapshot; 25struct btrfs_fs_info; 26struct btrfs_root_item; 27struct btrfs_root; 28struct btrfs_path; 29 30/* Radix-tree tag for roots that are part of the trasaction. */ 31#define BTRFS_ROOT_TRANS_TAG 0 32 33enum btrfs_trans_state { 34 TRANS_STATE_RUNNING, 35 TRANS_STATE_COMMIT_PREP, 36 TRANS_STATE_COMMIT_START, 37 TRANS_STATE_COMMIT_DOING, 38 TRANS_STATE_UNBLOCKED, 39 TRANS_STATE_SUPER_COMMITTED, 40 TRANS_STATE_COMPLETED, 41 TRANS_STATE_MAX, 42}; 43 44#define BTRFS_TRANS_HAVE_FREE_BGS 0 45#define BTRFS_TRANS_DIRTY_BG_RUN 1 46#define BTRFS_TRANS_CACHE_ENOSPC 2 47 48struct btrfs_transaction { 49 u64 transid; 50 /* 51 * total external writers(USERSPACE/START/ATTACH) in this 52 * transaction, it must be zero before the transaction is 53 * being committed 54 */ 55 atomic_t num_extwriters; 56 /* 57 * total writers in this transaction, it must be zero before the 58 * transaction can end 59 */ 60 atomic_t num_writers; 61 refcount_t use_count; 62 63 unsigned long flags; 64 65 /* Be protected by fs_info->trans_lock when we want to change it. */ 66 enum btrfs_trans_state state; 67 int aborted; 68 struct list_head list; 69 struct extent_io_tree dirty_pages; 70 time64_t start_time; 71 wait_queue_head_t writer_wait; 72 wait_queue_head_t commit_wait; 73 struct list_head pending_snapshots; 74 struct list_head dev_update_list; 75 struct list_head switch_commits; 76 struct list_head dirty_bgs; 77 78 /* 79 * There is no explicit lock which protects io_bgs, rather its 80 * consistency is implied by the fact that all the sites which modify 81 * it do so under some form of transaction critical section, namely: 82 * 83 * - btrfs_start_dirty_block_groups - This function can only ever be 84 * run by one of the transaction committers. Refer to 85 * BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction 86 * 87 * - btrfs_write_dirty_blockgroups - this is called by 88 * commit_cowonly_roots from transaction critical section 89 * (TRANS_STATE_COMMIT_DOING) 90 * 91 * - btrfs_cleanup_dirty_bgs - called on transaction abort 92 */ 93 struct list_head io_bgs; 94 struct list_head dropped_roots; 95 struct extent_io_tree pinned_extents; 96 97 /* 98 * we need to make sure block group deletion doesn't race with 99 * free space cache writeout. This mutex keeps them from stomping 100 * on each other 101 */ 102 struct mutex cache_write_mutex; 103 spinlock_t dirty_bgs_lock; 104 /* Protected by spin lock fs_info->unused_bgs_lock. */ 105 struct list_head deleted_bgs; 106 spinlock_t dropped_roots_lock; 107 struct btrfs_delayed_ref_root delayed_refs; 108 struct btrfs_fs_info *fs_info; 109 110 /* 111 * Number of ordered extents the transaction must wait for before 112 * committing. These are ordered extents started by a fast fsync. 113 */ 114 atomic_t pending_ordered; 115 wait_queue_head_t pending_wait; 116}; 117 118enum { 119 ENUM_BIT(__TRANS_FREEZABLE), 120 ENUM_BIT(__TRANS_START), 121 ENUM_BIT(__TRANS_ATTACH), 122 ENUM_BIT(__TRANS_JOIN), 123 ENUM_BIT(__TRANS_JOIN_NOLOCK), 124 ENUM_BIT(__TRANS_DUMMY), 125 ENUM_BIT(__TRANS_JOIN_NOSTART), 126}; 127 128#define TRANS_START (__TRANS_START | __TRANS_FREEZABLE) 129#define TRANS_ATTACH (__TRANS_ATTACH) 130#define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE) 131#define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK) 132#define TRANS_JOIN_NOSTART (__TRANS_JOIN_NOSTART) 133 134#define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH) 135 136struct btrfs_trans_handle { 137 u64 transid; 138 u64 bytes_reserved; 139 u64 delayed_refs_bytes_reserved; 140 u64 chunk_bytes_reserved; 141 unsigned long delayed_ref_updates; 142 unsigned long delayed_ref_csum_deletions; 143 struct btrfs_transaction *transaction; 144 struct btrfs_block_rsv *block_rsv; 145 struct btrfs_block_rsv *orig_rsv; 146 /* Set by a task that wants to create a snapshot. */ 147 struct btrfs_pending_snapshot *pending_snapshot; 148 refcount_t use_count; 149 unsigned int type; 150 /* 151 * Error code of transaction abort, set outside of locks and must use 152 * the READ_ONCE/WRITE_ONCE access 153 */ 154 short aborted; 155 bool adding_csums; 156 bool allocating_chunk; 157 bool removing_chunk; 158 bool reloc_reserved; 159 bool in_fsync; 160 struct btrfs_fs_info *fs_info; 161 struct list_head new_bgs; 162 struct btrfs_block_rsv delayed_rsv; 163}; 164 165/* 166 * The abort status can be changed between calls and is not protected by locks. 167 * This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's 168 * set to a non-zero value it does not change, so the macro should be in checks 169 * but is not necessary for further reads of the value. 170 */ 171#define TRANS_ABORTED(trans) (unlikely(READ_ONCE((trans)->aborted))) 172 173struct btrfs_pending_snapshot { 174 struct dentry *dentry; 175 struct inode *dir; 176 struct btrfs_root *root; 177 struct btrfs_root_item *root_item; 178 struct btrfs_root *snap; 179 struct btrfs_qgroup_inherit *inherit; 180 struct btrfs_path *path; 181 /* block reservation for the operation */ 182 struct btrfs_block_rsv block_rsv; 183 /* extra metadata reservation for relocation */ 184 int error; 185 /* Preallocated anonymous block device number */ 186 dev_t anon_dev; 187 bool readonly; 188 struct list_head list; 189}; 190 191static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans, 192 struct btrfs_inode *inode) 193{ 194 spin_lock(&inode->lock); 195 inode->last_trans = trans->transaction->transid; 196 inode->last_sub_trans = btrfs_get_root_log_transid(inode->root); 197 inode->last_log_commit = inode->last_sub_trans - 1; 198 spin_unlock(&inode->lock); 199} 200 201/* 202 * Make qgroup codes to skip given qgroupid, means the old/new_roots for 203 * qgroup won't contain the qgroupid in it. 204 */ 205static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans, 206 u64 qgroupid) 207{ 208 struct btrfs_delayed_ref_root *delayed_refs; 209 210 delayed_refs = &trans->transaction->delayed_refs; 211 WARN_ON(delayed_refs->qgroup_to_skip); 212 delayed_refs->qgroup_to_skip = qgroupid; 213} 214 215static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans) 216{ 217 struct btrfs_delayed_ref_root *delayed_refs; 218 219 delayed_refs = &trans->transaction->delayed_refs; 220 WARN_ON(!delayed_refs->qgroup_to_skip); 221 delayed_refs->qgroup_to_skip = 0; 222} 223 224bool __cold abort_should_print_stack(int error); 225 226/* 227 * Call btrfs_abort_transaction as early as possible when an error condition is 228 * detected, that way the exact stack trace is reported for some errors. 229 */ 230#define btrfs_abort_transaction(trans, error) \ 231do { \ 232 bool first = false; \ 233 /* Report first abort since mount */ \ 234 if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED, \ 235 &((trans)->fs_info->fs_state))) { \ 236 first = true; \ 237 if (WARN(abort_should_print_stack(error), \ 238 KERN_ERR \ 239 "BTRFS: Transaction aborted (error %d)\n", \ 240 (error))) { \ 241 /* Stack trace printed. */ \ 242 } else { \ 243 btrfs_err((trans)->fs_info, \ 244 "Transaction aborted (error %d)", \ 245 (error)); \ 246 } \ 247 } \ 248 __btrfs_abort_transaction((trans), __func__, \ 249 __LINE__, (error), first); \ 250} while (0) 251 252int btrfs_end_transaction(struct btrfs_trans_handle *trans); 253struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, 254 unsigned int num_items); 255struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv( 256 struct btrfs_root *root, 257 unsigned int num_items); 258struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root); 259struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root); 260struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root); 261struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root); 262struct btrfs_trans_handle *btrfs_attach_transaction_barrier( 263 struct btrfs_root *root); 264int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid); 265 266void btrfs_add_dead_root(struct btrfs_root *root); 267void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info); 268int btrfs_clean_one_deleted_snapshot(struct btrfs_fs_info *fs_info); 269int btrfs_commit_transaction(struct btrfs_trans_handle *trans); 270void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans); 271int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans); 272bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans); 273void btrfs_throttle(struct btrfs_fs_info *fs_info); 274int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, 275 struct btrfs_root *root); 276int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info, 277 struct extent_io_tree *dirty_pages, int mark); 278int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark); 279int btrfs_transaction_blocked(struct btrfs_fs_info *info); 280void btrfs_put_transaction(struct btrfs_transaction *transaction); 281void btrfs_add_dropped_root(struct btrfs_trans_handle *trans, 282 struct btrfs_root *root); 283void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans); 284void __cold __btrfs_abort_transaction(struct btrfs_trans_handle *trans, 285 const char *function, 286 unsigned int line, int error, bool first_hit); 287 288int __init btrfs_transaction_init(void); 289void __cold btrfs_transaction_exit(void); 290 291#endif 292