/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*/
#ifndef BTRFS_TRANSACTION_H
#define BTRFS_TRANSACTION_H
#include <linux/atomic.h>
#include <linux/refcount.h>
#include <linux/list.h>
#include <linux/time64.h>
#include <linux/mutex.h>
#include <linux/wait.h>
#include "btrfs_inode.h"
#include "delayed-ref.h"
#include "extent-io-tree.h"
#include "block-rsv.h"
#include "messages.h"
#include "misc.h"
struct dentry;
struct inode;
struct btrfs_pending_snapshot;
struct btrfs_fs_info;
struct btrfs_root_item;
struct btrfs_root;
struct btrfs_path;
/*
* Signal that a direct IO write is in progress, to avoid deadlock for sync
* direct IO writes when fsync is called during the direct IO write path.
*/
#define BTRFS_TRANS_DIO_WRITE_STUB ((void *) 1)
/* Radix-tree tag for roots that are part of the trasaction. */
#define BTRFS_ROOT_TRANS_TAG 0
enum btrfs_trans_state {
TRANS_STATE_RUNNING,
TRANS_STATE_COMMIT_PREP,
TRANS_STATE_COMMIT_START,
TRANS_STATE_COMMIT_DOING,
TRANS_STATE_UNBLOCKED,
TRANS_STATE_SUPER_COMMITTED,
TRANS_STATE_COMPLETED,
TRANS_STATE_MAX,
};
#define BTRFS_TRANS_HAVE_FREE_BGS 0
#define BTRFS_TRANS_DIRTY_BG_RUN 1
#define BTRFS_TRANS_CACHE_ENOSPC 2
struct btrfs_transaction {
u64 transid;
/*
* total external writers(USERSPACE/START/ATTACH) in this
* transaction, it must be zero before the transaction is
* being committed
*/
atomic_t num_extwriters;
/*
* total writers in this transaction, it must be zero before the
* transaction can end
*/
atomic_t num_writers;
refcount_t use_count;
unsigned long flags;
/* Be protected by fs_info->trans_lock when we want to change it. */
enum btrfs_trans_state state;
int aborted;
struct list_head list;
struct extent_io_tree dirty_pages;
time64_t start_time;
wait_queue_head_t writer_wait;
wait_queue_head_t commit_wait;
struct list_head pending_snapshots;
struct list_head dev_update_list;
struct list_head switch_commits;
struct list_head dirty_bgs;
/*
* There is no explicit lock which protects io_bgs, rather its
* consistency is implied by the fact that all the sites which modify
* it do so under some form of transaction critical section, namely:
*
* - btrfs_start_dirty_block_groups - This function can only ever be
* run by one of the transaction committers. Refer to
* BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction
*
* - btrfs_write_dirty_blockgroups - this is called by
* commit_cowonly_roots from transaction critical section
* (TRANS_STATE_COMMIT_DOING)
*
* - btrfs_cleanup_dirty_bgs - called on transaction abort
*/
struct list_head io_bgs;
struct list_head dropped_roots;
struct extent_io_tree pinned_extents;
/*
* we need to make sure block group deletion doesn't race with
* free space cache writeout. This mutex keeps them from stomping
* on each other
*/
struct mutex cache_write_mutex;
spinlock_t dirty_bgs_lock;
/* Protected by spin lock fs_info->unused_bgs_lock. */
struct list_head deleted_bgs;
spinlock_t dropped_roots_lock;
struct btrfs_delayed_ref_root delayed_refs;
struct btrfs_fs_info *fs_info;
/*
* Number of ordered extents the transaction must wait for before
* committing. These are ordered extents started by a fast fsync.
*/
atomic_t pending_ordered;
wait_queue_head_t pending_wait;
};
enum {
ENUM_BIT(__TRANS_FREEZABLE),
ENUM_BIT(__TRANS_START),
ENUM_BIT(__TRANS_ATTACH),
ENUM_BIT(__TRANS_JOIN),
ENUM_BIT(__TRANS_JOIN_NOLOCK),
ENUM_BIT(__TRANS_DUMMY),
ENUM_BIT(__TRANS_JOIN_NOSTART),
};
#define TRANS_START (__TRANS_START | __TRANS_FREEZABLE)
#define TRANS_ATTACH (__TRANS_ATTACH)
#define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE)
#define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK)
#define TRANS_JOIN_NOSTART (__TRANS_JOIN_NOSTART)
#define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH)
struct btrfs_trans_handle {
u64 transid;
u64 bytes_reserved;
u64 delayed_refs_bytes_reserved;
u64 chunk_bytes_reserved;
unsigned long delayed_ref_updates;
unsigned long delayed_ref_csum_deletions;
struct btrfs_transaction *transaction;
struct btrfs_block_rsv *block_rsv;
struct btrfs_block_rsv *orig_rsv;
/* Set by a task that wants to create a snapshot. */
struct btrfs_pending_snapshot *pending_snapshot;
refcount_t use_count;
unsigned int type;
/*
* Error code of transaction abort, set outside of locks and must use
* the READ_ONCE/WRITE_ONCE access
*/
short aborted;
bool adding_csums;
bool allocating_chunk;
bool removing_chunk;
bool reloc_reserved;
bool in_fsync;
struct btrfs_fs_info *fs_info;
struct list_head new_bgs;
struct btrfs_block_rsv delayed_rsv;
};
/*
* The abort status can be changed between calls and is not protected by locks.
* This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's
* set to a non-zero value it does not change, so the macro should be in checks
* but is not necessary for further reads of the value.
*/
#define TRANS_ABORTED(trans) (unlikely(READ_ONCE((trans)->aborted)))
struct btrfs_pending_snapshot {
struct dentry *dentry;
struct btrfs_inode *dir;
struct btrfs_root *root;
struct btrfs_root_item *root_item;
struct btrfs_root *snap;
struct btrfs_qgroup_inherit *inherit;
struct btrfs_path *path;
/* block reservation for the operation */
struct btrfs_block_rsv block_rsv;
/* extra metadata reservation for relocation */
int error;
/* Preallocated anonymous block device number */
dev_t anon_dev;
bool readonly;
struct list_head list;
};
static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,
struct btrfs_inode *inode)
{
spin_lock(&inode->lock);
inode->last_trans = trans->transaction->transid;
inode->last_sub_trans = btrfs_get_root_log_transid(inode->root);
inode->last_log_commit = inode->last_sub_trans - 1;
spin_unlock(&inode->lock);
}
/*
* Make qgroup codes to skip given qgroupid, means the old/new_roots for
* qgroup won't contain the qgroupid in it.
*/
static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans,
u64 qgroupid)
{
struct btrfs_delayed_ref_root *delayed_refs;
delayed_refs = &trans->transaction->delayed_refs;
WARN_ON(delayed_refs->qgroup_to_skip);
delayed_refs->qgroup_to_skip = qgroupid;
}
static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans)
{
struct btrfs_delayed_ref_root *delayed_refs;
delayed_refs = &trans->transaction->delayed_refs;
WARN_ON(!delayed_refs->qgroup_to_skip);
delayed_refs->qgroup_to_skip = 0;
}
bool __cold abort_should_print_stack(int error);
/*
* Call btrfs_abort_transaction as early as possible when an error condition is
* detected, that way the exact stack trace is reported for some errors.
*/
#define btrfs_abort_transaction(trans, error) \
do { \
bool __first = false; \
/* Report first abort since mount */ \
if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED, \
&((trans)->fs_info->fs_state))) { \
__first = true; \
if (WARN(abort_should_print_stack(error), \
KERN_ERR \
"BTRFS: Transaction aborted (error %d)\n", \
(error))) { \
/* Stack trace printed. */ \
} else { \
btrfs_err((trans)->fs_info, \
"Transaction aborted (error %d)", \
(error)); \
} \
} \
__btrfs_abort_transaction((trans), __func__, \
__LINE__, (error), __first); \
} while (0)
int btrfs_end_transaction(struct btrfs_trans_handle *trans);
struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
unsigned int num_items);
struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
struct btrfs_root *root,
unsigned int num_items);
struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root);
struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root);
struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
struct btrfs_root *root);
int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
void btrfs_add_dead_root(struct btrfs_root *root);
void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info);
int btrfs_clean_one_deleted_snapshot(struct btrfs_fs_info *fs_info);
int btrfs_commit_transaction(struct btrfs_trans_handle *trans);
void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans);
int btrfs_commit_current_transaction(struct btrfs_root *root);
int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans);
bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans);
void btrfs_throttle(struct btrfs_fs_info *fs_info);
int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
struct extent_io_tree *dirty_pages, int mark);
int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark);
int btrfs_transaction_blocked(struct btrfs_fs_info *info);
void btrfs_put_transaction(struct btrfs_transaction *transaction);
void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans);
void __cold __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
const char *function,
unsigned int line, int error, bool first_hit);
int __init btrfs_transaction_init(void);
void __cold btrfs_transaction_exit(void);
#endif
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