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Diffstat (limited to 'fs/xfs/xfs_bmap_item.h')
| -rw-r--r-- | fs/xfs/xfs_bmap_item.h | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/fs/xfs/xfs_bmap_item.h b/fs/xfs/xfs_bmap_item.h new file mode 100644 index 000000000000..57c13d3a9b03 --- /dev/null +++ b/fs/xfs/xfs_bmap_item.h @@ -0,0 +1,97 @@ +/* + * Copyright (C) 2016 Oracle. All Rights Reserved. + * + * Author: Darrick J. Wong <darrick.wong@oracle.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. + */ +#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 + +/* + * Define BUI flag bits. Manipulated by set/clear/test_bit operators. + */ +#define XFS_BUI_RECOVERED 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; + unsigned long bui_flags; /* misc flags */ + 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; + +struct xfs_bui_log_item *xfs_bui_init(struct xfs_mount *); +struct xfs_bud_log_item *xfs_bud_init(struct xfs_mount *, + struct xfs_bui_log_item *); +void xfs_bui_item_free(struct xfs_bui_log_item *); +void xfs_bui_release(struct xfs_bui_log_item *); + +#endif /* __XFS_BMAP_ITEM_H__ */ |