1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2016 Oracle. All Rights Reserved.
4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
5 */
6 #ifndef __XFS_REFCOUNT_H__
7 #define __XFS_REFCOUNT_H__
8
9 extern int xfs_refcount_lookup_le(struct xfs_btree_cur *cur,
10 xfs_agblock_t bno, int *stat);
11 extern int xfs_refcount_lookup_ge(struct xfs_btree_cur *cur,
12 xfs_agblock_t bno, int *stat);
13 extern int xfs_refcount_lookup_eq(struct xfs_btree_cur *cur,
14 xfs_agblock_t bno, int *stat);
15 extern int xfs_refcount_get_rec(struct xfs_btree_cur *cur,
16 struct xfs_refcount_irec *irec, int *stat);
17
18 enum xfs_refcount_intent_type {
19 XFS_REFCOUNT_INCREASE = 1,
20 XFS_REFCOUNT_DECREASE,
21 XFS_REFCOUNT_ALLOC_COW,
22 XFS_REFCOUNT_FREE_COW,
23 };
24
25 struct xfs_refcount_intent {
26 struct list_head ri_list;
27 enum xfs_refcount_intent_type ri_type;
28 xfs_fsblock_t ri_startblock;
29 xfs_extlen_t ri_blockcount;
30 };
31
32 extern int xfs_refcount_increase_extent(struct xfs_trans *tp,
33 struct xfs_bmbt_irec *irec);
34 extern int xfs_refcount_decrease_extent(struct xfs_trans *tp,
35 struct xfs_bmbt_irec *irec);
36
37 extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp,
38 struct xfs_btree_cur *rcur, int error);
39 extern int xfs_refcount_finish_one(struct xfs_trans *tp,
40 enum xfs_refcount_intent_type type, xfs_fsblock_t startblock,
41 xfs_extlen_t blockcount, xfs_fsblock_t *new_fsb,
42 xfs_extlen_t *new_len, struct xfs_btree_cur **pcur);
43
44 extern int xfs_refcount_find_shared(struct xfs_btree_cur *cur,
45 xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno,
46 xfs_extlen_t *flen, bool find_end_of_shared);
47
48 extern int xfs_refcount_alloc_cow_extent(struct xfs_trans *tp,
49 xfs_fsblock_t fsb, xfs_extlen_t len);
50 extern int xfs_refcount_free_cow_extent(struct xfs_trans *tp,
51 xfs_fsblock_t fsb, xfs_extlen_t len);
52 extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp,
53 xfs_agnumber_t agno);
54
55 /*
56 * While we're adjusting the refcounts records of an extent, we have
57 * to keep an eye on the number of extents we're dirtying -- run too
58 * many in a single transaction and we'll exceed the transaction's
59 * reservation and crash the fs. Each record adds 12 bytes to the
60 * log (plus any key updates) so we'll conservatively assume 32 bytes
61 * per record. We must also leave space for btree splits on both ends
62 * of the range and space for the CUD and a new CUI.
63 */
64 #define XFS_REFCOUNT_ITEM_OVERHEAD 32
65
xfs_refcount_max_unmap(int log_res)66 static inline xfs_fileoff_t xfs_refcount_max_unmap(int log_res)
67 {
68 return (log_res * 3 / 4) / XFS_REFCOUNT_ITEM_OVERHEAD;
69 }
70
71 extern int xfs_refcount_has_record(struct xfs_btree_cur *cur,
72 xfs_agblock_t bno, xfs_extlen_t len, bool *exists);
73 union xfs_btree_rec;
74 extern void xfs_refcount_btrec_to_irec(union xfs_btree_rec *rec,
75 struct xfs_refcount_irec *irec);
76 extern int xfs_refcount_insert(struct xfs_btree_cur *cur,
77 struct xfs_refcount_irec *irec, int *stat);
78
79 #endif /* __XFS_REFCOUNT_H__ */
80