linux/fs/xfs/libxfs/xfs_defer.h
Darrick J. Wong c5db9f937b xfs: formalize the process of holding onto resources across a defer roll
Transaction users are allowed to flag up to two buffers and two inodes
for ownership preservation across a deferred transaction roll.  Hoist
the variables and code responsible for this out of xfs_defer_trans_roll
so that we can use it for the defer capture mechanism.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
2021-10-14 09:19:31 -07:00

128 lines
3.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (C) 2016 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*/
#ifndef __XFS_DEFER_H__
#define __XFS_DEFER_H__
struct xfs_btree_cur;
struct xfs_defer_op_type;
struct xfs_defer_capture;
/*
* Header for deferred operation list.
*/
enum xfs_defer_ops_type {
XFS_DEFER_OPS_TYPE_BMAP,
XFS_DEFER_OPS_TYPE_REFCOUNT,
XFS_DEFER_OPS_TYPE_RMAP,
XFS_DEFER_OPS_TYPE_FREE,
XFS_DEFER_OPS_TYPE_AGFL_FREE,
XFS_DEFER_OPS_TYPE_MAX,
};
/*
* Save a log intent item and a list of extents, so that we can replay
* whatever action had to happen to the extent list and file the log done
* item.
*/
struct xfs_defer_pending {
struct list_head dfp_list; /* pending items */
struct list_head dfp_work; /* work items */
struct xfs_log_item *dfp_intent; /* log intent item */
struct xfs_log_item *dfp_done; /* log done item */
unsigned int dfp_count; /* # extent items */
enum xfs_defer_ops_type dfp_type;
};
void xfs_defer_add(struct xfs_trans *tp, enum xfs_defer_ops_type type,
struct list_head *h);
int xfs_defer_finish_noroll(struct xfs_trans **tp);
int xfs_defer_finish(struct xfs_trans **tp);
void xfs_defer_cancel(struct xfs_trans *);
void xfs_defer_move(struct xfs_trans *dtp, struct xfs_trans *stp);
/* Description of a deferred type. */
struct xfs_defer_op_type {
struct xfs_log_item *(*create_intent)(struct xfs_trans *tp,
struct list_head *items, unsigned int count, bool sort);
void (*abort_intent)(struct xfs_log_item *intent);
struct xfs_log_item *(*create_done)(struct xfs_trans *tp,
struct xfs_log_item *intent, unsigned int count);
int (*finish_item)(struct xfs_trans *tp, struct xfs_log_item *done,
struct list_head *item, struct xfs_btree_cur **state);
void (*finish_cleanup)(struct xfs_trans *tp,
struct xfs_btree_cur *state, int error);
void (*cancel_item)(struct list_head *item);
unsigned int max_items;
};
extern const struct xfs_defer_op_type xfs_bmap_update_defer_type;
extern const struct xfs_defer_op_type xfs_refcount_update_defer_type;
extern const struct xfs_defer_op_type xfs_rmap_update_defer_type;
extern const struct xfs_defer_op_type xfs_extent_free_defer_type;
extern const struct xfs_defer_op_type xfs_agfl_free_defer_type;
/*
* Deferred operation item relogging limits.
*/
#define XFS_DEFER_OPS_NR_INODES 2 /* join up to two inodes */
#define XFS_DEFER_OPS_NR_BUFS 2 /* join up to two buffers */
/* Resources that must be held across a transaction roll. */
struct xfs_defer_resources {
/* held buffers */
struct xfs_buf *dr_bp[XFS_DEFER_OPS_NR_BUFS];
/* inodes with no unlock flags */
struct xfs_inode *dr_ip[XFS_DEFER_OPS_NR_INODES];
/* number of held buffers */
unsigned short dr_bufs;
/* bitmap of ordered buffers */
unsigned short dr_ordered;
/* number of held inodes */
unsigned short dr_inos;
};
/*
* This structure enables a dfops user to detach the chain of deferred
* operations from a transaction so that they can be continued later.
*/
struct xfs_defer_capture {
/* List of other capture structures. */
struct list_head dfc_list;
/* Deferred ops state saved from the transaction. */
struct list_head dfc_dfops;
unsigned int dfc_tpflags;
/* Block reservations for the data and rt devices. */
unsigned int dfc_blkres;
unsigned int dfc_rtxres;
/* Log reservation saved from the transaction. */
unsigned int dfc_logres;
/*
* An inode reference that must be maintained to complete the deferred
* work.
*/
struct xfs_inode *dfc_capture_ip;
};
/*
* Functions to capture a chain of deferred operations and continue them later.
* This doesn't normally happen except log recovery.
*/
int xfs_defer_ops_capture_and_commit(struct xfs_trans *tp,
struct xfs_inode *capture_ip, struct list_head *capture_list);
void xfs_defer_ops_continue(struct xfs_defer_capture *d, struct xfs_trans *tp,
struct xfs_inode **captured_ipp);
void xfs_defer_ops_release(struct xfs_mount *mp, struct xfs_defer_capture *d);
#endif /* __XFS_DEFER_H__ */