// SPDX-License-Identifier: GPL-2.0+ /* * Copyright (C) 2016 Oracle. All Rights Reserved. * Author: Darrick J. Wong <darrick.wong@oracle.com> */ #ifndef __XFS_BMAP_ITEM_H__ #define __XFS_BMAP_ITEM_H__ /* * There are (currently) two pairs of bmap btree redo item types: map & unmap. * The common abbreviations for these are BUI (bmap update intent) and BUD * (bmap update done). The redo item type is encoded in the flags field of * each xfs_map_extent. * * *I items should be recorded in the *first* of a series of rolled * transactions, and the *D items should be recorded in the same transaction * that records the associated bmbt updates. * * Should the system crash after the commit of the first transaction but * before the commit of the final transaction in a series, log recovery will * use the redo information recorded by the intent items to replay the * bmbt metadata updates in the non-first transaction. */ /* kernel only BUI/BUD definitions */ struct xfs_mount; struct kmem_zone; /* * Max number of extents in fast allocation path. */ #define XFS_BUI_MAX_FAST_EXTENTS 1 /* * This is the "bmap update intent" log item. It is used to log the fact that * some reverse mappings need to change. It is used in conjunction with the * "bmap update done" log item described below. * * These log items follow the same rules as struct xfs_efi_log_item; see the * comments about that structure (in xfs_extfree_item.h) for more details. */ struct xfs_bui_log_item { struct xfs_log_item bui_item; atomic_t bui_refcount; atomic_t bui_next_extent; struct xfs_bui_log_format bui_format; }; static inline size_t xfs_bui_log_item_sizeof( unsigned int nr) { return offsetof(struct xfs_bui_log_item, bui_format) + xfs_bui_log_format_sizeof(nr); } /* * This is the "bmap update done" log item. It is used to log the fact that * some bmbt updates mentioned in an earlier bui item have been performed. */ struct xfs_bud_log_item { struct xfs_log_item bud_item; struct xfs_bui_log_item *bud_buip; struct xfs_bud_log_format bud_format; }; extern struct kmem_zone *xfs_bui_zone; extern struct kmem_zone *xfs_bud_zone; #endif /* __XFS_BMAP_ITEM_H__ */