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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Copyright (C) 2007 Oracle. All rights reserved.4 */5 6#ifndef BTRFS_TRANSACTION_H7#define BTRFS_TRANSACTION_H8 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/*31 * Signal that a direct IO write is in progress, to avoid deadlock for sync32 * direct IO writes when fsync is called during the direct IO write path.33 */34#define BTRFS_TRANS_DIO_WRITE_STUB ((void *) 1)35 36/* Radix-tree tag for roots that are part of the trasaction. */37#define BTRFS_ROOT_TRANS_TAG 038 39enum btrfs_trans_state {40 TRANS_STATE_RUNNING,41 TRANS_STATE_COMMIT_PREP,42 TRANS_STATE_COMMIT_START,43 TRANS_STATE_COMMIT_DOING,44 TRANS_STATE_UNBLOCKED,45 TRANS_STATE_SUPER_COMMITTED,46 TRANS_STATE_COMPLETED,47 TRANS_STATE_MAX,48};49 50#define BTRFS_TRANS_HAVE_FREE_BGS 051#define BTRFS_TRANS_DIRTY_BG_RUN 152#define BTRFS_TRANS_CACHE_ENOSPC 253 54struct btrfs_transaction {55 u64 transid;56 /*57 * total external writers(USERSPACE/START/ATTACH) in this58 * transaction, it must be zero before the transaction is59 * being committed60 */61 atomic_t num_extwriters;62 /*63 * total writers in this transaction, it must be zero before the64 * transaction can end65 */66 atomic_t num_writers;67 refcount_t use_count;68 69 unsigned long flags;70 71 /* Be protected by fs_info->trans_lock when we want to change it. */72 enum btrfs_trans_state state;73 int aborted;74 struct list_head list;75 struct extent_io_tree dirty_pages;76 time64_t start_time;77 wait_queue_head_t writer_wait;78 wait_queue_head_t commit_wait;79 struct list_head pending_snapshots;80 struct list_head dev_update_list;81 struct list_head switch_commits;82 struct list_head dirty_bgs;83 84 /*85 * There is no explicit lock which protects io_bgs, rather its86 * consistency is implied by the fact that all the sites which modify87 * it do so under some form of transaction critical section, namely:88 *89 * - btrfs_start_dirty_block_groups - This function can only ever be90 * run by one of the transaction committers. Refer to91 * BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction92 *93 * - btrfs_write_dirty_blockgroups - this is called by94 * commit_cowonly_roots from transaction critical section95 * (TRANS_STATE_COMMIT_DOING)96 *97 * - btrfs_cleanup_dirty_bgs - called on transaction abort98 */99 struct list_head io_bgs;100 struct list_head dropped_roots;101 struct extent_io_tree pinned_extents;102 103 /*104 * we need to make sure block group deletion doesn't race with105 * free space cache writeout. This mutex keeps them from stomping106 * on each other107 */108 struct mutex cache_write_mutex;109 spinlock_t dirty_bgs_lock;110 /* Protected by spin lock fs_info->unused_bgs_lock. */111 struct list_head deleted_bgs;112 spinlock_t dropped_roots_lock;113 struct btrfs_delayed_ref_root delayed_refs;114 struct btrfs_fs_info *fs_info;115 116 /*117 * Number of ordered extents the transaction must wait for before118 * committing. These are ordered extents started by a fast fsync.119 */120 atomic_t pending_ordered;121 wait_queue_head_t pending_wait;122};123 124enum {125 ENUM_BIT(__TRANS_FREEZABLE),126 ENUM_BIT(__TRANS_START),127 ENUM_BIT(__TRANS_ATTACH),128 ENUM_BIT(__TRANS_JOIN),129 ENUM_BIT(__TRANS_JOIN_NOLOCK),130 ENUM_BIT(__TRANS_DUMMY),131 ENUM_BIT(__TRANS_JOIN_NOSTART),132};133 134#define TRANS_START (__TRANS_START | __TRANS_FREEZABLE)135#define TRANS_ATTACH (__TRANS_ATTACH)136#define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE)137#define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK)138#define TRANS_JOIN_NOSTART (__TRANS_JOIN_NOSTART)139 140#define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH)141 142struct btrfs_trans_handle {143 u64 transid;144 u64 bytes_reserved;145 u64 delayed_refs_bytes_reserved;146 u64 chunk_bytes_reserved;147 unsigned long delayed_ref_updates;148 unsigned long delayed_ref_csum_deletions;149 struct btrfs_transaction *transaction;150 struct btrfs_block_rsv *block_rsv;151 struct btrfs_block_rsv *orig_rsv;152 /* Set by a task that wants to create a snapshot. */153 struct btrfs_pending_snapshot *pending_snapshot;154 refcount_t use_count;155 unsigned int type;156 /*157 * Error code of transaction abort, set outside of locks and must use158 * the READ_ONCE/WRITE_ONCE access159 */160 short aborted;161 bool adding_csums;162 bool allocating_chunk;163 bool removing_chunk;164 bool reloc_reserved;165 bool in_fsync;166 struct btrfs_fs_info *fs_info;167 struct list_head new_bgs;168 struct btrfs_block_rsv delayed_rsv;169};170 171/*172 * The abort status can be changed between calls and is not protected by locks.173 * This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's174 * set to a non-zero value it does not change, so the macro should be in checks175 * but is not necessary for further reads of the value.176 */177#define TRANS_ABORTED(trans) (unlikely(READ_ONCE((trans)->aborted)))178 179struct btrfs_pending_snapshot {180 struct dentry *dentry;181 struct btrfs_inode *dir;182 struct btrfs_root *root;183 struct btrfs_root_item *root_item;184 struct btrfs_root *snap;185 struct btrfs_qgroup_inherit *inherit;186 struct btrfs_path *path;187 /* block reservation for the operation */188 struct btrfs_block_rsv block_rsv;189 /* extra metadata reservation for relocation */190 int error;191 /* Preallocated anonymous block device number */192 dev_t anon_dev;193 bool readonly;194 struct list_head list;195};196 197static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,198 struct btrfs_inode *inode)199{200 spin_lock(&inode->lock);201 inode->last_trans = trans->transaction->transid;202 inode->last_sub_trans = btrfs_get_root_log_transid(inode->root);203 inode->last_log_commit = inode->last_sub_trans - 1;204 spin_unlock(&inode->lock);205}206 207/*208 * Make qgroup codes to skip given qgroupid, means the old/new_roots for209 * qgroup won't contain the qgroupid in it.210 */211static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans,212 u64 qgroupid)213{214 struct btrfs_delayed_ref_root *delayed_refs;215 216 delayed_refs = &trans->transaction->delayed_refs;217 WARN_ON(delayed_refs->qgroup_to_skip);218 delayed_refs->qgroup_to_skip = qgroupid;219}220 221static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans)222{223 struct btrfs_delayed_ref_root *delayed_refs;224 225 delayed_refs = &trans->transaction->delayed_refs;226 WARN_ON(!delayed_refs->qgroup_to_skip);227 delayed_refs->qgroup_to_skip = 0;228}229 230bool __cold abort_should_print_stack(int error);231 232/*233 * Call btrfs_abort_transaction as early as possible when an error condition is234 * detected, that way the exact stack trace is reported for some errors.235 */236#define btrfs_abort_transaction(trans, error) \237do { \238 bool __first = false; \239 /* Report first abort since mount */ \240 if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED, \241 &((trans)->fs_info->fs_state))) { \242 __first = true; \243 if (WARN(abort_should_print_stack(error), \244 KERN_ERR \245 "BTRFS: Transaction aborted (error %d)\n", \246 (error))) { \247 /* Stack trace printed. */ \248 } else { \249 btrfs_err((trans)->fs_info, \250 "Transaction aborted (error %d)", \251 (error)); \252 } \253 } \254 __btrfs_abort_transaction((trans), __func__, \255 __LINE__, (error), __first); \256} while (0)257 258int btrfs_end_transaction(struct btrfs_trans_handle *trans);259struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,260 unsigned int num_items);261struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(262 struct btrfs_root *root,263 unsigned int num_items);264struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);265struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root);266struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root);267struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);268struct btrfs_trans_handle *btrfs_attach_transaction_barrier(269 struct btrfs_root *root);270int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);271 272void btrfs_add_dead_root(struct btrfs_root *root);273void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info);274int btrfs_clean_one_deleted_snapshot(struct btrfs_fs_info *fs_info);275int btrfs_commit_transaction(struct btrfs_trans_handle *trans);276void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans);277int btrfs_commit_current_transaction(struct btrfs_root *root);278int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans);279bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans);280void btrfs_throttle(struct btrfs_fs_info *fs_info);281int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,282 struct btrfs_root *root);283int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,284 struct extent_io_tree *dirty_pages, int mark);285int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark);286int btrfs_transaction_blocked(struct btrfs_fs_info *info);287void btrfs_put_transaction(struct btrfs_transaction *transaction);288void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,289 struct btrfs_root *root);290void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans);291void __cold __btrfs_abort_transaction(struct btrfs_trans_handle *trans,292 const char *function,293 unsigned int line, int error, bool first_hit);294 295int __init btrfs_transaction_init(void);296void __cold btrfs_transaction_exit(void);297 298#endif299