1 /* 2 * Copyright (C) 2016 Oracle. All Rights Reserved. 3 * 4 * Author: Darrick J. Wong <darrick.wong@oracle.com> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 2 9 * of the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it would be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. 19 */ 20 #ifndef __XFS_REFCOUNT_H__ 21 #define __XFS_REFCOUNT_H__ 22 23 extern int xfs_refcount_lookup_le(struct xfs_btree_cur *cur, 24 xfs_agblock_t bno, int *stat); 25 extern int xfs_refcount_lookup_ge(struct xfs_btree_cur *cur, 26 xfs_agblock_t bno, int *stat); 27 extern int xfs_refcount_lookup_eq(struct xfs_btree_cur *cur, 28 xfs_agblock_t bno, int *stat); 29 extern int xfs_refcount_get_rec(struct xfs_btree_cur *cur, 30 struct xfs_refcount_irec *irec, int *stat); 31 32 enum xfs_refcount_intent_type { 33 XFS_REFCOUNT_INCREASE = 1, 34 XFS_REFCOUNT_DECREASE, 35 XFS_REFCOUNT_ALLOC_COW, 36 XFS_REFCOUNT_FREE_COW, 37 }; 38 39 struct xfs_refcount_intent { 40 struct list_head ri_list; 41 enum xfs_refcount_intent_type ri_type; 42 xfs_fsblock_t ri_startblock; 43 xfs_extlen_t ri_blockcount; 44 }; 45 46 extern int xfs_refcount_increase_extent(struct xfs_mount *mp, 47 struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec); 48 extern int xfs_refcount_decrease_extent(struct xfs_mount *mp, 49 struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec); 50 51 extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp, 52 struct xfs_btree_cur *rcur, int error); 53 extern int xfs_refcount_finish_one(struct xfs_trans *tp, 54 struct xfs_defer_ops *dfops, enum xfs_refcount_intent_type type, 55 xfs_fsblock_t startblock, xfs_extlen_t blockcount, 56 xfs_fsblock_t *new_fsb, xfs_extlen_t *new_len, 57 struct xfs_btree_cur **pcur); 58 59 extern int xfs_refcount_find_shared(struct xfs_btree_cur *cur, 60 xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno, 61 xfs_extlen_t *flen, bool find_end_of_shared); 62 63 extern int xfs_refcount_alloc_cow_extent(struct xfs_mount *mp, 64 struct xfs_defer_ops *dfops, xfs_fsblock_t fsb, 65 xfs_extlen_t len); 66 extern int xfs_refcount_free_cow_extent(struct xfs_mount *mp, 67 struct xfs_defer_ops *dfops, xfs_fsblock_t fsb, 68 xfs_extlen_t len); 69 extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp, 70 xfs_agnumber_t agno); 71 72 /* 73 * While we're adjusting the refcounts records of an extent, we have 74 * to keep an eye on the number of extents we're dirtying -- run too 75 * many in a single transaction and we'll exceed the transaction's 76 * reservation and crash the fs. Each record adds 12 bytes to the 77 * log (plus any key updates) so we'll conservatively assume 32 bytes 78 * per record. We must also leave space for btree splits on both ends 79 * of the range and space for the CUD and a new CUI. 80 */ 81 #define XFS_REFCOUNT_ITEM_OVERHEAD 32 82 83 static inline xfs_fileoff_t xfs_refcount_max_unmap(int log_res) 84 { 85 return (log_res * 3 / 4) / XFS_REFCOUNT_ITEM_OVERHEAD; 86 } 87 88 extern int xfs_refcount_has_record(struct xfs_btree_cur *cur, 89 xfs_agblock_t bno, xfs_extlen_t len, bool *exists); 90 union xfs_btree_rec; 91 extern void xfs_refcount_btrec_to_irec(union xfs_btree_rec *rec, 92 struct xfs_refcount_irec *irec); 93 extern int xfs_refcount_insert(struct xfs_btree_cur *cur, 94 struct xfs_refcount_irec *irec, int *stat); 95 96 #endif /* __XFS_REFCOUNT_H__ */ 97