Dave Chinner | 0b61f8a | 2018-06-05 19:42:14 -0700 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
Darrick J. Wong | baf4bcac | 2016-10-03 09:11:20 -0700 | [diff] [blame] | 2 | /* |
| 3 | * Copyright (C) 2016 Oracle. All Rights Reserved. |
Darrick J. Wong | baf4bcac | 2016-10-03 09:11:20 -0700 | [diff] [blame] | 4 | * Author: Darrick J. Wong <darrick.wong@oracle.com> |
Darrick J. Wong | baf4bcac | 2016-10-03 09:11:20 -0700 | [diff] [blame] | 5 | */ |
| 6 | #ifndef __XFS_REFCOUNT_ITEM_H__ |
| 7 | #define __XFS_REFCOUNT_ITEM_H__ |
| 8 | |
| 9 | /* |
| 10 | * There are (currently) two pairs of refcount btree redo item types: |
| 11 | * increase and decrease. The log items for these are CUI (refcount |
| 12 | * update intent) and CUD (refcount update done). The redo item type |
| 13 | * is encoded in the flags field of each xfs_map_extent. |
| 14 | * |
| 15 | * *I items should be recorded in the *first* of a series of rolled |
| 16 | * transactions, and the *D items should be recorded in the same |
| 17 | * transaction that records the associated refcountbt updates. |
| 18 | * |
| 19 | * Should the system crash after the commit of the first transaction |
| 20 | * but before the commit of the final transaction in a series, log |
| 21 | * recovery will use the redo information recorded by the intent items |
| 22 | * to replay the refcountbt metadata updates. |
| 23 | */ |
| 24 | |
| 25 | /* kernel only CUI/CUD definitions */ |
| 26 | |
| 27 | struct xfs_mount; |
| 28 | struct kmem_zone; |
| 29 | |
| 30 | /* |
| 31 | * Max number of extents in fast allocation path. |
| 32 | */ |
| 33 | #define XFS_CUI_MAX_FAST_EXTENTS 16 |
| 34 | |
| 35 | /* |
Darrick J. Wong | baf4bcac | 2016-10-03 09:11:20 -0700 | [diff] [blame] | 36 | * This is the "refcount update intent" log item. It is used to log |
| 37 | * the fact that some reverse mappings need to change. It is used in |
| 38 | * conjunction with the "refcount update done" log item described |
| 39 | * below. |
| 40 | * |
| 41 | * These log items follow the same rules as struct xfs_efi_log_item; |
| 42 | * see the comments about that structure (in xfs_extfree_item.h) for |
| 43 | * more details. |
| 44 | */ |
| 45 | struct xfs_cui_log_item { |
| 46 | struct xfs_log_item cui_item; |
| 47 | atomic_t cui_refcount; |
| 48 | atomic_t cui_next_extent; |
Darrick J. Wong | baf4bcac | 2016-10-03 09:11:20 -0700 | [diff] [blame] | 49 | struct xfs_cui_log_format cui_format; |
| 50 | }; |
| 51 | |
| 52 | static inline size_t |
| 53 | xfs_cui_log_item_sizeof( |
| 54 | unsigned int nr) |
| 55 | { |
| 56 | return offsetof(struct xfs_cui_log_item, cui_format) + |
| 57 | xfs_cui_log_format_sizeof(nr); |
| 58 | } |
| 59 | |
| 60 | /* |
| 61 | * This is the "refcount update done" log item. It is used to log the |
| 62 | * fact that some refcountbt updates mentioned in an earlier cui item |
| 63 | * have been performed. |
| 64 | */ |
| 65 | struct xfs_cud_log_item { |
| 66 | struct xfs_log_item cud_item; |
| 67 | struct xfs_cui_log_item *cud_cuip; |
| 68 | struct xfs_cud_log_format cud_format; |
| 69 | }; |
| 70 | |
| 71 | extern struct kmem_zone *xfs_cui_zone; |
| 72 | extern struct kmem_zone *xfs_cud_zone; |
| 73 | |
Darrick J. Wong | baf4bcac | 2016-10-03 09:11:20 -0700 | [diff] [blame] | 74 | #endif /* __XFS_REFCOUNT_ITEM_H__ */ |