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 struct xfs_trans;
10 struct xfs_mount;
11 struct xfs_perag;
12 struct xfs_btree_cur;
13 struct xfs_bmbt_irec;
14 struct xfs_refcount_irec;
15
16 extern int xfs_refcount_lookup_le(struct xfs_btree_cur *cur,
17 xfs_agblock_t bno, int *stat);
18 extern int xfs_refcount_lookup_ge(struct xfs_btree_cur *cur,
19 xfs_agblock_t bno, int *stat);
20 extern int xfs_refcount_lookup_eq(struct xfs_btree_cur *cur,
21 xfs_agblock_t bno, int *stat);
22 extern int xfs_refcount_get_rec(struct xfs_btree_cur *cur,
23 struct xfs_refcount_irec *irec, int *stat);
24
25 enum xfs_refcount_intent_type {
26 XFS_REFCOUNT_INCREASE = 1,
27 XFS_REFCOUNT_DECREASE,
28 XFS_REFCOUNT_ALLOC_COW,
29 XFS_REFCOUNT_FREE_COW,
30 };
31
32 struct xfs_refcount_intent {
33 struct list_head ri_list;
34 enum xfs_refcount_intent_type ri_type;
35 xfs_fsblock_t ri_startblock;
36 xfs_extlen_t ri_blockcount;
37 };
38
39 void xfs_refcount_increase_extent(struct xfs_trans *tp,
40 struct xfs_bmbt_irec *irec);
41 void xfs_refcount_decrease_extent(struct xfs_trans *tp,
42 struct xfs_bmbt_irec *irec);
43
44 extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp,
45 struct xfs_btree_cur *rcur, int error);
46 extern int xfs_refcount_finish_one(struct xfs_trans *tp,
47 enum xfs_refcount_intent_type type, xfs_fsblock_t startblock,
48 xfs_extlen_t blockcount, xfs_fsblock_t *new_fsb,
49 xfs_extlen_t *new_len, struct xfs_btree_cur **pcur);
50
51 extern int xfs_refcount_find_shared(struct xfs_btree_cur *cur,
52 xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno,
53 xfs_extlen_t *flen, bool find_end_of_shared);
54
55 void xfs_refcount_alloc_cow_extent(struct xfs_trans *tp, xfs_fsblock_t fsb,
56 xfs_extlen_t len);
57 void xfs_refcount_free_cow_extent(struct xfs_trans *tp, xfs_fsblock_t fsb,
58 xfs_extlen_t len);
59 extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp,
60 struct xfs_perag *pag);
61
62 /*
63 * While we're adjusting the refcounts records of an extent, we have
64 * to keep an eye on the number of extents we're dirtying -- run too
65 * many in a single transaction and we'll exceed the transaction's
66 * reservation and crash the fs. Each record adds 12 bytes to the
67 * log (plus any key updates) so we'll conservatively assume 32 bytes
68 * per record. We must also leave space for btree splits on both ends
69 * of the range and space for the CUD and a new CUI.
70 */
71 #define XFS_REFCOUNT_ITEM_OVERHEAD 32
72
xfs_refcount_max_unmap(int log_res)73 static inline xfs_fileoff_t xfs_refcount_max_unmap(int log_res)
74 {
75 return (log_res * 3 / 4) / XFS_REFCOUNT_ITEM_OVERHEAD;
76 }
77
78 extern int xfs_refcount_has_record(struct xfs_btree_cur *cur,
79 xfs_agblock_t bno, xfs_extlen_t len, bool *exists);
80 union xfs_btree_rec;
81 extern void xfs_refcount_btrec_to_irec(const union xfs_btree_rec *rec,
82 struct xfs_refcount_irec *irec);
83 extern int xfs_refcount_insert(struct xfs_btree_cur *cur,
84 struct xfs_refcount_irec *irec, int *stat);
85
86 #endif /* __XFS_REFCOUNT_H__ */
87
