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 void xfs_refcount_increase_extent(struct xfs_trans *tp, 33 struct xfs_bmbt_irec *irec); 34 void 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 void xfs_refcount_alloc_cow_extent(struct xfs_trans *tp, xfs_fsblock_t fsb, 49 xfs_extlen_t len); 50 void xfs_refcount_free_cow_extent(struct xfs_trans *tp, xfs_fsblock_t fsb, 51 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 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