1 /* 2 * Copyright (C) 2016 Oracle. All Rights Reserved. 3 * 4 * Author: Darrick J. Wong <darrick.wong@oracle.com> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 2 9 * of the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it would be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. 19 */ 20 #ifndef __XFS_RMAP_ITEM_H__ 21 #define __XFS_RMAP_ITEM_H__ 22 23 /* 24 * There are (currently) three pairs of rmap btree redo item types: map, unmap, 25 * and convert. The common abbreviations for these are RUI (rmap update 26 * intent) and RUD (rmap update done). The redo item type is encoded in the 27 * flags field of each xfs_map_extent. 28 * 29 * *I items should be recorded in the *first* of a series of rolled 30 * transactions, and the *D items should be recorded in the same transaction 31 * that records the associated rmapbt updates. Typically, the first 32 * transaction will record a bmbt update, followed by some number of 33 * transactions containing rmapbt updates, and finally transactions with any 34 * bnobt/cntbt updates. 35 * 36 * Should the system crash after the commit of the first transaction but 37 * before the commit of the final transaction in a series, log recovery will 38 * use the redo information recorded by the intent items to replay the 39 * (rmapbt/bnobt/cntbt) metadata updates in the non-first transaction. 40 */ 41 42 /* kernel only RUI/RUD definitions */ 43 44 struct xfs_mount; 45 struct kmem_zone; 46 47 /* 48 * Max number of extents in fast allocation path. 49 */ 50 #define XFS_RUI_MAX_FAST_EXTENTS 16 51 52 /* 53 * Define RUI flag bits. Manipulated by set/clear/test_bit operators. 54 */ 55 #define XFS_RUI_RECOVERED 1 56 57 /* 58 * This is the "rmap update intent" log item. It is used to log the fact that 59 * some reverse mappings need to change. It is used in conjunction with the 60 * "rmap update done" log item described below. 61 * 62 * These log items follow the same rules as struct xfs_efi_log_item; see the 63 * comments about that structure (in xfs_extfree_item.h) for more details. 64 */ 65 struct xfs_rui_log_item { 66 struct xfs_log_item rui_item; 67 atomic_t rui_refcount; 68 atomic_t rui_next_extent; 69 unsigned long rui_flags; /* misc flags */ 70 struct xfs_rui_log_format rui_format; 71 }; 72 73 /* 74 * This is the "rmap update done" log item. It is used to log the fact that 75 * some rmapbt updates mentioned in an earlier rui item have been performed. 76 */ 77 struct xfs_rud_log_item { 78 struct xfs_log_item rud_item; 79 struct xfs_rui_log_item *rud_ruip; 80 struct xfs_rud_log_format rud_format; 81 }; 82 83 extern struct kmem_zone *xfs_rui_zone; 84 extern struct kmem_zone *xfs_rud_zone; 85 86 struct xfs_rui_log_item *xfs_rui_init(struct xfs_mount *, uint); 87 struct xfs_rud_log_item *xfs_rud_init(struct xfs_mount *, 88 struct xfs_rui_log_item *); 89 int xfs_rui_copy_format(struct xfs_log_iovec *buf, 90 struct xfs_rui_log_format *dst_rui_fmt); 91 void xfs_rui_item_free(struct xfs_rui_log_item *); 92 void xfs_rui_release(struct xfs_rui_log_item *); 93 int xfs_rui_recover(struct xfs_mount *mp, struct xfs_rui_log_item *ruip); 94 95 #endif /* __XFS_RMAP_ITEM_H__ */ 96