// SPDX-License-Identifier: GPL-2.0+ /* * Copyright (C) 2016 Oracle. All Rights Reserved. * Author: Darrick J. Wong <darrick.wong@oracle.com> */ #ifndef __XFS_RMAP_ITEM_H__ #define __XFS_RMAP_ITEM_H__ /* * There are (currently) three pairs of rmap btree redo item types: map, unmap, * and convert. The common abbreviations for these are RUI (rmap update * intent) and RUD (rmap 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 rmapbt updates. Typically, the first * transaction will record a bmbt update, followed by some number of * transactions containing rmapbt updates, and finally transactions with any * bnobt/cntbt 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 * (rmapbt/bnobt/cntbt) metadata updates in the non-first transaction. */ /* kernel only RUI/RUD definitions */ struct xfs_mount; struct kmem_cache; /* * Max number of extents in fast allocation path. */ #define XFS_RUI_MAX_FAST_EXTENTS 16 /* * This is the "rmap 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 * "rmap 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_rui_log_item { struct xfs_log_item rui_item; atomic_t rui_refcount; atomic_t rui_next_extent; struct xfs_rui_log_format rui_format; }; static inline size_t xfs_rui_log_item_sizeof( unsigned int nr) { return offsetof(struct xfs_rui_log_item, rui_format) + xfs_rui_log_format_sizeof(nr); } /* * This is the "rmap update done" log item. It is used to log the fact that * some rmapbt updates mentioned in an earlier rui item have been performed. */ struct xfs_rud_log_item { struct xfs_log_item rud_item; struct xfs_rui_log_item *rud_ruip; struct xfs_rud_log_format rud_format; }; extern struct kmem_cache *xfs_rui_cache; extern struct kmem_cache *xfs_rud_cache; #endif /* __XFS_RMAP_ITEM_H__ */