xref: /linux/fs/xfs/xfs_refcount_item.h (revision 0b61f8a4079d904b1b1d47946cca898313de8c26)
1*0b61f8a4SDave Chinner // SPDX-License-Identifier: GPL-2.0+
2baf4bcacSDarrick J. Wong /*
3baf4bcacSDarrick J. Wong  * Copyright (C) 2016 Oracle.  All Rights Reserved.
4baf4bcacSDarrick J. Wong  * Author: Darrick J. Wong <darrick.wong@oracle.com>
5baf4bcacSDarrick J. Wong  */
6baf4bcacSDarrick J. Wong #ifndef	__XFS_REFCOUNT_ITEM_H__
7baf4bcacSDarrick J. Wong #define	__XFS_REFCOUNT_ITEM_H__
8baf4bcacSDarrick J. Wong 
9baf4bcacSDarrick J. Wong /*
10baf4bcacSDarrick J. Wong  * There are (currently) two pairs of refcount btree redo item types:
11baf4bcacSDarrick J. Wong  * increase and decrease.  The log items for these are CUI (refcount
12baf4bcacSDarrick J. Wong  * update intent) and CUD (refcount update done).  The redo item type
13baf4bcacSDarrick J. Wong  * is encoded in the flags field of each xfs_map_extent.
14baf4bcacSDarrick J. Wong  *
15baf4bcacSDarrick J. Wong  * *I items should be recorded in the *first* of a series of rolled
16baf4bcacSDarrick J. Wong  * transactions, and the *D items should be recorded in the same
17baf4bcacSDarrick J. Wong  * transaction that records the associated refcountbt updates.
18baf4bcacSDarrick J. Wong  *
19baf4bcacSDarrick J. Wong  * Should the system crash after the commit of the first transaction
20baf4bcacSDarrick J. Wong  * but before the commit of the final transaction in a series, log
21baf4bcacSDarrick J. Wong  * recovery will use the redo information recorded by the intent items
22baf4bcacSDarrick J. Wong  * to replay the refcountbt metadata updates.
23baf4bcacSDarrick J. Wong  */
24baf4bcacSDarrick J. Wong 
25baf4bcacSDarrick J. Wong /* kernel only CUI/CUD definitions */
26baf4bcacSDarrick J. Wong 
27baf4bcacSDarrick J. Wong struct xfs_mount;
28baf4bcacSDarrick J. Wong struct kmem_zone;
29baf4bcacSDarrick J. Wong 
30baf4bcacSDarrick J. Wong /*
31baf4bcacSDarrick J. Wong  * Max number of extents in fast allocation path.
32baf4bcacSDarrick J. Wong  */
33baf4bcacSDarrick J. Wong #define	XFS_CUI_MAX_FAST_EXTENTS	16
34baf4bcacSDarrick J. Wong 
35baf4bcacSDarrick J. Wong /*
36baf4bcacSDarrick J. Wong  * Define CUI flag bits. Manipulated by set/clear/test_bit operators.
37baf4bcacSDarrick J. Wong  */
38baf4bcacSDarrick J. Wong #define	XFS_CUI_RECOVERED		1
39baf4bcacSDarrick J. Wong 
40baf4bcacSDarrick J. Wong /*
41baf4bcacSDarrick J. Wong  * This is the "refcount update intent" log item.  It is used to log
42baf4bcacSDarrick J. Wong  * the fact that some reverse mappings need to change.  It is used in
43baf4bcacSDarrick J. Wong  * conjunction with the "refcount update done" log item described
44baf4bcacSDarrick J. Wong  * below.
45baf4bcacSDarrick J. Wong  *
46baf4bcacSDarrick J. Wong  * These log items follow the same rules as struct xfs_efi_log_item;
47baf4bcacSDarrick J. Wong  * see the comments about that structure (in xfs_extfree_item.h) for
48baf4bcacSDarrick J. Wong  * more details.
49baf4bcacSDarrick J. Wong  */
50baf4bcacSDarrick J. Wong struct xfs_cui_log_item {
51baf4bcacSDarrick J. Wong 	struct xfs_log_item		cui_item;
52baf4bcacSDarrick J. Wong 	atomic_t			cui_refcount;
53baf4bcacSDarrick J. Wong 	atomic_t			cui_next_extent;
54baf4bcacSDarrick J. Wong 	unsigned long			cui_flags;	/* misc flags */
55baf4bcacSDarrick J. Wong 	struct xfs_cui_log_format	cui_format;
56baf4bcacSDarrick J. Wong };
57baf4bcacSDarrick J. Wong 
58baf4bcacSDarrick J. Wong static inline size_t
59baf4bcacSDarrick J. Wong xfs_cui_log_item_sizeof(
60baf4bcacSDarrick J. Wong 	unsigned int		nr)
61baf4bcacSDarrick J. Wong {
62baf4bcacSDarrick J. Wong 	return offsetof(struct xfs_cui_log_item, cui_format) +
63baf4bcacSDarrick J. Wong 			xfs_cui_log_format_sizeof(nr);
64baf4bcacSDarrick J. Wong }
65baf4bcacSDarrick J. Wong 
66baf4bcacSDarrick J. Wong /*
67baf4bcacSDarrick J. Wong  * This is the "refcount update done" log item.  It is used to log the
68baf4bcacSDarrick J. Wong  * fact that some refcountbt updates mentioned in an earlier cui item
69baf4bcacSDarrick J. Wong  * have been performed.
70baf4bcacSDarrick J. Wong  */
71baf4bcacSDarrick J. Wong struct xfs_cud_log_item {
72baf4bcacSDarrick J. Wong 	struct xfs_log_item		cud_item;
73baf4bcacSDarrick J. Wong 	struct xfs_cui_log_item		*cud_cuip;
74baf4bcacSDarrick J. Wong 	struct xfs_cud_log_format	cud_format;
75baf4bcacSDarrick J. Wong };
76baf4bcacSDarrick J. Wong 
77baf4bcacSDarrick J. Wong extern struct kmem_zone	*xfs_cui_zone;
78baf4bcacSDarrick J. Wong extern struct kmem_zone	*xfs_cud_zone;
79baf4bcacSDarrick J. Wong 
80baf4bcacSDarrick J. Wong struct xfs_cui_log_item *xfs_cui_init(struct xfs_mount *, uint);
81baf4bcacSDarrick J. Wong struct xfs_cud_log_item *xfs_cud_init(struct xfs_mount *,
82baf4bcacSDarrick J. Wong 		struct xfs_cui_log_item *);
83baf4bcacSDarrick J. Wong void xfs_cui_item_free(struct xfs_cui_log_item *);
84baf4bcacSDarrick J. Wong void xfs_cui_release(struct xfs_cui_log_item *);
8550995582SDarrick J. Wong int xfs_cui_recover(struct xfs_mount *mp, struct xfs_cui_log_item *cuip,
8650995582SDarrick J. Wong 		struct xfs_defer_ops *dfops);
87baf4bcacSDarrick J. Wong 
88baf4bcacSDarrick J. Wong #endif	/* __XFS_REFCOUNT_ITEM_H__ */
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