LXR linux/fs/xfs/libxfs/xfs

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2016 Oracle.  All Rights Reserved.
   4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
   5 */
   6#ifndef __XFS_DEFER_H__
   7#define __XFS_DEFER_H__
   8
   9struct xfs_defer_op_type;
  10
  11/*
  12 * Save a log intent item and a list of extents, so that we can replay
  13 * whatever action had to happen to the extent list and file the log done
  14 * item.
  15 */
  16struct xfs_defer_pending {
  17        const struct xfs_defer_op_type  *dfp_type;      /* function pointers */
  18        struct list_head                dfp_list;       /* pending items */
  19        void                            *dfp_intent;    /* log intent item */
  20        void                            *dfp_done;      /* log done item */
  21        struct list_head                dfp_work;       /* work items */
  22        unsigned int                    dfp_count;      /* # extent items */
  23};
  24
  25/*
  26 * Header for deferred operation list.
  27 *
  28 * dop_low is used by the allocator to activate the lowspace algorithm -
  29 * when free space is running low the extent allocator may choose to
  30 * allocate an extent from an AG without leaving sufficient space for
  31 * a btree split when inserting the new extent.  In this case the allocator
  32 * will enable the lowspace algorithm which is supposed to allow further
  33 * allocations (such as btree splits and newroots) to allocate from
  34 * sequential AGs.  In order to avoid locking AGs out of order the lowspace
  35 * algorithm will start searching for free space from AG 0.  If the correct
  36 * transaction reservations have been made then this algorithm will eventually
  37 * find all the space it needs.
  38 */
  39enum xfs_defer_ops_type {
  40        XFS_DEFER_OPS_TYPE_BMAP,
  41        XFS_DEFER_OPS_TYPE_REFCOUNT,
  42        XFS_DEFER_OPS_TYPE_RMAP,
  43        XFS_DEFER_OPS_TYPE_FREE,
  44        XFS_DEFER_OPS_TYPE_AGFL_FREE,
  45        XFS_DEFER_OPS_TYPE_MAX,
  46};
  47
  48#define XFS_DEFER_OPS_NR_INODES 2       /* join up to two inodes */
  49#define XFS_DEFER_OPS_NR_BUFS   2       /* join up to two buffers */
  50
  51struct xfs_defer_ops {
  52        bool                    dop_committed;  /* did any trans commit? */
  53        bool                    dop_low;        /* alloc in low mode */
  54        struct list_head        dop_intake;     /* unlogged pending work */
  55        struct list_head        dop_pending;    /* logged pending work */
  56
  57        /* relog these with each roll */
  58        struct xfs_inode        *dop_inodes[XFS_DEFER_OPS_NR_INODES];
  59        struct xfs_buf          *dop_bufs[XFS_DEFER_OPS_NR_BUFS];
  60};
  61
  62void xfs_defer_add(struct xfs_defer_ops *dop, enum xfs_defer_ops_type type,
  63                struct list_head *h);
  64int xfs_defer_finish(struct xfs_trans **tp, struct xfs_defer_ops *dop);
  65void xfs_defer_cancel(struct xfs_defer_ops *dop);
  66void xfs_defer_init(struct xfs_defer_ops *dop, xfs_fsblock_t *fbp);
  67bool xfs_defer_has_unfinished_work(struct xfs_defer_ops *dop);
  68int xfs_defer_ijoin(struct xfs_defer_ops *dop, struct xfs_inode *ip);
  69int xfs_defer_bjoin(struct xfs_defer_ops *dop, struct xfs_buf *bp);
  70
  71/* Description of a deferred type. */
  72struct xfs_defer_op_type {
  73        enum xfs_defer_ops_type type;
  74        unsigned int            max_items;
  75        void (*abort_intent)(void *);
  76        void *(*create_done)(struct xfs_trans *, void *, unsigned int);
  77        int (*finish_item)(struct xfs_trans *, struct xfs_defer_ops *,
  78                        struct list_head *, void *, void **);
  79        void (*finish_cleanup)(struct xfs_trans *, void *, int);
  80        void (*cancel_item)(struct list_head *);
  81        int (*diff_items)(void *, struct list_head *, struct list_head *);
  82        void *(*create_intent)(struct xfs_trans *, uint);
  83        void (*log_item)(struct xfs_trans *, void *, struct list_head *);
  84};
  85
  86void xfs_defer_init_op_type(const struct xfs_defer_op_type *type);
  87
  88#endif /* __XFS_DEFER_H__ */
  89