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 struct xfs_rtgroup; 16 17 extern int xfs_refcount_lookup_le(struct xfs_btree_cur *cur, 18 enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat); 19 extern int xfs_refcount_lookup_ge(struct xfs_btree_cur *cur, 20 enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat); 21 extern int xfs_refcount_lookup_eq(struct xfs_btree_cur *cur, 22 enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat); 23 extern int xfs_refcount_get_rec(struct xfs_btree_cur *cur, 24 struct xfs_refcount_irec *irec, int *stat); 25 26 static inline uint32_t 27 xfs_refcount_encode_startblock( 28 xfs_agblock_t startblock, 29 enum xfs_refc_domain domain) 30 { 31 uint32_t start; 32 33 /* 34 * low level btree operations need to handle the generic btree range 35 * query functions (which set rc_domain == -1U), so we check that the 36 * domain is /not/ shared. 37 */ 38 start = startblock & ~XFS_REFC_COWFLAG; 39 if (domain != XFS_REFC_DOMAIN_SHARED) 40 start |= XFS_REFC_COWFLAG; 41 42 return start; 43 } 44 45 enum xfs_refcount_intent_type { 46 XFS_REFCOUNT_INCREASE = 1, 47 XFS_REFCOUNT_DECREASE, 48 XFS_REFCOUNT_ALLOC_COW, 49 XFS_REFCOUNT_FREE_COW, 50 }; 51 52 #define XFS_REFCOUNT_INTENT_STRINGS \ 53 { XFS_REFCOUNT_INCREASE, "incr" }, \ 54 { XFS_REFCOUNT_DECREASE, "decr" }, \ 55 { XFS_REFCOUNT_ALLOC_COW, "alloc_cow" }, \ 56 { XFS_REFCOUNT_FREE_COW, "free_cow" } 57 58 struct xfs_refcount_intent { 59 struct list_head ri_list; 60 struct xfs_group *ri_group; 61 enum xfs_refcount_intent_type ri_type; 62 xfs_extlen_t ri_blockcount; 63 xfs_fsblock_t ri_startblock; 64 bool ri_realtime; 65 }; 66 67 /* Check that the refcount is appropriate for the record domain. */ 68 static inline bool 69 xfs_refcount_check_domain( 70 const struct xfs_refcount_irec *irec) 71 { 72 if (irec->rc_domain == XFS_REFC_DOMAIN_COW && irec->rc_refcount != 1) 73 return false; 74 if (irec->rc_domain == XFS_REFC_DOMAIN_SHARED && irec->rc_refcount < 2) 75 return false; 76 return true; 77 } 78 79 void xfs_refcount_increase_extent(struct xfs_trans *tp, bool isrt, 80 struct xfs_bmbt_irec *irec); 81 void xfs_refcount_decrease_extent(struct xfs_trans *tp, bool isrt, 82 struct xfs_bmbt_irec *irec); 83 84 int xfs_refcount_finish_one(struct xfs_trans *tp, 85 struct xfs_refcount_intent *ri, struct xfs_btree_cur **pcur); 86 int xfs_rtrefcount_finish_one(struct xfs_trans *tp, 87 struct xfs_refcount_intent *ri, struct xfs_btree_cur **pcur); 88 89 extern int xfs_refcount_find_shared(struct xfs_btree_cur *cur, 90 xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno, 91 xfs_extlen_t *flen, bool find_end_of_shared); 92 93 void xfs_refcount_alloc_cow_extent(struct xfs_trans *tp, bool isrt, 94 xfs_fsblock_t fsb, xfs_extlen_t len); 95 void xfs_refcount_free_cow_extent(struct xfs_trans *tp, bool isrt, 96 xfs_fsblock_t fsb, xfs_extlen_t len); 97 int xfs_refcount_recover_cow_leftovers(struct xfs_group *xg); 98 99 /* 100 * While we're adjusting the refcounts records of an extent, we have 101 * to keep an eye on the number of extents we're dirtying -- run too 102 * many in a single transaction and we'll exceed the transaction's 103 * reservation and crash the fs. Each record adds 12 bytes to the 104 * log (plus any key updates) so we'll conservatively assume 32 bytes 105 * per record. We must also leave space for btree splits on both ends 106 * of the range and space for the CUD and a new CUI. 107 * 108 * Each EFI that we attach to the transaction is assumed to consume ~32 bytes. 109 * This is a low estimate for an EFI tracking a single extent (16 bytes for the 110 * EFI header, 16 for the extent, and 12 for the xlog op header), but the 111 * estimate is acceptable if there's more than one extent being freed. 112 * In the worst case of freeing every other block during a refcount decrease 113 * operation, we amortize the space used for one EFI log item across 16 114 * extents. 115 */ 116 #define XFS_REFCOUNT_ITEM_OVERHEAD 32 117 118 extern int xfs_refcount_has_records(struct xfs_btree_cur *cur, 119 enum xfs_refc_domain domain, xfs_agblock_t bno, 120 xfs_extlen_t len, enum xbtree_recpacking *outcome); 121 union xfs_btree_rec; 122 extern void xfs_refcount_btrec_to_irec(const union xfs_btree_rec *rec, 123 struct xfs_refcount_irec *irec); 124 xfs_failaddr_t xfs_refcount_check_irec(struct xfs_perag *pag, 125 const struct xfs_refcount_irec *irec); 126 xfs_failaddr_t xfs_rtrefcount_check_irec(struct xfs_rtgroup *rtg, 127 const struct xfs_refcount_irec *irec); 128 extern int xfs_refcount_insert(struct xfs_btree_cur *cur, 129 struct xfs_refcount_irec *irec, int *stat); 130 131 extern struct kmem_cache *xfs_refcount_intent_cache; 132 133 int __init xfs_refcount_intent_init_cache(void); 134 void xfs_refcount_intent_destroy_cache(void); 135 136 typedef int (*xfs_refcount_query_range_fn)( 137 struct xfs_btree_cur *cur, 138 const struct xfs_refcount_irec *rec, 139 void *priv); 140 141 int xfs_refcount_query_range(struct xfs_btree_cur *cur, 142 const struct xfs_refcount_irec *low_rec, 143 const struct xfs_refcount_irec *high_rec, 144 xfs_refcount_query_range_fn fn, void *priv); 145 146 #endif /* __XFS_REFCOUNT_H__ */ 147