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 | enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat); |
18 | extern int xfs_refcount_lookup_ge(struct xfs_btree_cur *cur, |
19 | enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat); |
20 | extern int xfs_refcount_lookup_eq(struct xfs_btree_cur *cur, |
21 | enum xfs_refc_domain domain, 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 | static inline uint32_t |
26 | xfs_refcount_encode_startblock( |
27 | xfs_agblock_t startblock, |
28 | enum xfs_refc_domain domain) |
29 | { |
30 | uint32_t start; |
31 | |
32 | /* |
33 | * low level btree operations need to handle the generic btree range |
34 | * query functions (which set rc_domain == -1U), so we check that the |
35 | * domain is /not/ shared. |
36 | */ |
37 | start = startblock & ~XFS_REFC_COWFLAG; |
38 | if (domain != XFS_REFC_DOMAIN_SHARED) |
39 | start |= XFS_REFC_COWFLAG; |
40 | |
41 | return start; |
42 | } |
43 | |
44 | enum xfs_refcount_intent_type { |
45 | XFS_REFCOUNT_INCREASE = 1, |
46 | XFS_REFCOUNT_DECREASE, |
47 | XFS_REFCOUNT_ALLOC_COW, |
48 | XFS_REFCOUNT_FREE_COW, |
49 | }; |
50 | |
51 | struct xfs_refcount_intent { |
52 | struct list_head ri_list; |
53 | struct xfs_perag *ri_pag; |
54 | enum xfs_refcount_intent_type ri_type; |
55 | xfs_extlen_t ri_blockcount; |
56 | xfs_fsblock_t ri_startblock; |
57 | }; |
58 | |
59 | /* Check that the refcount is appropriate for the record domain. */ |
60 | static inline bool |
61 | xfs_refcount_check_domain( |
62 | const struct xfs_refcount_irec *irec) |
63 | { |
64 | if (irec->rc_domain == XFS_REFC_DOMAIN_COW && irec->rc_refcount != 1) |
65 | return false; |
66 | if (irec->rc_domain == XFS_REFC_DOMAIN_SHARED && irec->rc_refcount < 2) |
67 | return false; |
68 | return true; |
69 | } |
70 | |
71 | void xfs_refcount_update_get_group(struct xfs_mount *mp, |
72 | struct xfs_refcount_intent *ri); |
73 | |
74 | void xfs_refcount_increase_extent(struct xfs_trans *tp, |
75 | struct xfs_bmbt_irec *irec); |
76 | void xfs_refcount_decrease_extent(struct xfs_trans *tp, |
77 | struct xfs_bmbt_irec *irec); |
78 | |
79 | extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp, |
80 | struct xfs_btree_cur *rcur, int error); |
81 | extern int xfs_refcount_finish_one(struct xfs_trans *tp, |
82 | struct xfs_refcount_intent *ri, struct xfs_btree_cur **pcur); |
83 | |
84 | extern int xfs_refcount_find_shared(struct xfs_btree_cur *cur, |
85 | xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno, |
86 | xfs_extlen_t *flen, bool find_end_of_shared); |
87 | |
88 | void xfs_refcount_alloc_cow_extent(struct xfs_trans *tp, xfs_fsblock_t fsb, |
89 | xfs_extlen_t len); |
90 | void xfs_refcount_free_cow_extent(struct xfs_trans *tp, xfs_fsblock_t fsb, |
91 | xfs_extlen_t len); |
92 | extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp, |
93 | struct xfs_perag *pag); |
94 | |
95 | /* |
96 | * While we're adjusting the refcounts records of an extent, we have |
97 | * to keep an eye on the number of extents we're dirtying -- run too |
98 | * many in a single transaction and we'll exceed the transaction's |
99 | * reservation and crash the fs. Each record adds 12 bytes to the |
100 | * log (plus any key updates) so we'll conservatively assume 32 bytes |
101 | * per record. We must also leave space for btree splits on both ends |
102 | * of the range and space for the CUD and a new CUI. |
103 | * |
104 | * Each EFI that we attach to the transaction is assumed to consume ~32 bytes. |
105 | * This is a low estimate for an EFI tracking a single extent (16 bytes for the |
106 | * EFI header, 16 for the extent, and 12 for the xlog op header), but the |
107 | * estimate is acceptable if there's more than one extent being freed. |
108 | * In the worst case of freeing every other block during a refcount decrease |
109 | * operation, we amortize the space used for one EFI log item across 16 |
110 | * extents. |
111 | */ |
112 | #define XFS_REFCOUNT_ITEM_OVERHEAD 32 |
113 | |
114 | extern int xfs_refcount_has_records(struct xfs_btree_cur *cur, |
115 | enum xfs_refc_domain domain, xfs_agblock_t bno, |
116 | xfs_extlen_t len, enum xbtree_recpacking *outcome); |
117 | union xfs_btree_rec; |
118 | extern void xfs_refcount_btrec_to_irec(const union xfs_btree_rec *rec, |
119 | struct xfs_refcount_irec *irec); |
120 | xfs_failaddr_t xfs_refcount_check_irec(struct xfs_perag *pag, |
121 | const struct xfs_refcount_irec *irec); |
122 | extern int xfs_refcount_insert(struct xfs_btree_cur *cur, |
123 | struct xfs_refcount_irec *irec, int *stat); |
124 | |
125 | extern struct kmem_cache *xfs_refcount_intent_cache; |
126 | |
127 | int __init xfs_refcount_intent_init_cache(void); |
128 | void xfs_refcount_intent_destroy_cache(void); |
129 | |
130 | typedef int (*xfs_refcount_query_range_fn)( |
131 | struct xfs_btree_cur *cur, |
132 | const struct xfs_refcount_irec *rec, |
133 | void *priv); |
134 | |
135 | int xfs_refcount_query_range(struct xfs_btree_cur *cur, |
136 | const struct xfs_refcount_irec *low_rec, |
137 | const struct xfs_refcount_irec *high_rec, |
138 | xfs_refcount_query_range_fn fn, void *priv); |
139 | |
140 | #endif /* __XFS_REFCOUNT_H__ */ |
141 | |