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Diffstat (limited to 'fs/xfs/xfs_refcount_item.h')
| -rw-r--r-- | fs/xfs/xfs_refcount_item.h | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/fs/xfs/xfs_refcount_item.h b/fs/xfs/xfs_refcount_item.h new file mode 100644 index 000000000000..34b6f7a8c149 --- /dev/null +++ b/fs/xfs/xfs_refcount_item.h @@ -0,0 +1,100 @@ +/* + * 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_REFCOUNT_ITEM_H__ +#define __XFS_REFCOUNT_ITEM_H__ + +/* + * There are (currently) two pairs of refcount btree redo item types: + * increase and decrease. The log items for these are CUI (refcount + * update intent) and CUD (refcount 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 refcountbt 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 refcountbt metadata updates. + */ + +/* kernel only CUI/CUD definitions */ + +struct xfs_mount; +struct kmem_zone; + +/* + * Max number of extents in fast allocation path. + */ +#define XFS_CUI_MAX_FAST_EXTENTS 16 + +/* + * Define CUI flag bits. Manipulated by set/clear/test_bit operators. + */ +#define XFS_CUI_RECOVERED 1 + +/* + * This is the "refcount 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 "refcount 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_cui_log_item { + struct xfs_log_item cui_item; + atomic_t cui_refcount; + atomic_t cui_next_extent; + unsigned long cui_flags; /* misc flags */ + struct xfs_cui_log_format cui_format; +}; + +static inline size_t +xfs_cui_log_item_sizeof( + unsigned int nr) +{ + return offsetof(struct xfs_cui_log_item, cui_format) + + xfs_cui_log_format_sizeof(nr); +} + +/* + * This is the "refcount update done" log item. It is used to log the + * fact that some refcountbt updates mentioned in an earlier cui item + * have been performed. + */ +struct xfs_cud_log_item { + struct xfs_log_item cud_item; + struct xfs_cui_log_item *cud_cuip; + struct xfs_cud_log_format cud_format; +}; + +extern struct kmem_zone *xfs_cui_zone; +extern struct kmem_zone *xfs_cud_zone; + +struct xfs_cui_log_item *xfs_cui_init(struct xfs_mount *, uint); +struct xfs_cud_log_item *xfs_cud_init(struct xfs_mount *, + struct xfs_cui_log_item *); +void xfs_cui_item_free(struct xfs_cui_log_item *); +void xfs_cui_release(struct xfs_cui_log_item *); + +#endif /* __XFS_REFCOUNT_ITEM_H__ */ |