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_get_rec(struct xfs_btree_cur *cur, 28 struct xfs_refcount_irec *irec, int *stat); 29 30 enum xfs_refcount_intent_type { 31 XFS_REFCOUNT_INCREASE = 1, 32 XFS_REFCOUNT_DECREASE, 33 XFS_REFCOUNT_ALLOC_COW, 34 XFS_REFCOUNT_FREE_COW, 35 }; 36 37 struct xfs_refcount_intent { 38 struct list_head ri_list; 39 enum xfs_refcount_intent_type ri_type; 40 xfs_fsblock_t ri_startblock; 41 xfs_extlen_t ri_blockcount; 42 }; 43 44 extern int xfs_refcount_increase_extent(struct xfs_mount *mp, 45 struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec); 46 extern int xfs_refcount_decrease_extent(struct xfs_mount *mp, 47 struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec); 48 49 extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp, 50 struct xfs_btree_cur *rcur, int error); 51 extern int xfs_refcount_finish_one(struct xfs_trans *tp, 52 struct xfs_defer_ops *dfops, enum xfs_refcount_intent_type type, 53 xfs_fsblock_t startblock, xfs_extlen_t blockcount, 54 xfs_fsblock_t *new_fsb, xfs_extlen_t *new_len, 55 struct xfs_btree_cur **pcur); 56 57 extern int xfs_refcount_find_shared(struct xfs_btree_cur *cur, 58 xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno, 59 xfs_extlen_t *flen, bool find_end_of_shared); 60 61 extern int xfs_refcount_alloc_cow_extent(struct xfs_mount *mp, 62 struct xfs_defer_ops *dfops, xfs_fsblock_t fsb, 63 xfs_extlen_t len); 64 extern int xfs_refcount_free_cow_extent(struct xfs_mount *mp, 65 struct xfs_defer_ops *dfops, xfs_fsblock_t fsb, 66 xfs_extlen_t len); 67 extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp, 68 xfs_agnumber_t agno); 69 70 /* 71 * While we're adjusting the refcounts records of an extent, we have 72 * to keep an eye on the number of extents we're dirtying -- run too 73 * many in a single transaction and we'll exceed the transaction's 74 * reservation and crash the fs. Each record adds 12 bytes to the 75 * log (plus any key updates) so we'll conservatively assume 32 bytes 76 * per record. We must also leave space for btree splits on both ends 77 * of the range and space for the CUD and a new CUI. 78 */ 79 #define XFS_REFCOUNT_ITEM_OVERHEAD 32 80 81 static inline xfs_fileoff_t xfs_refcount_max_unmap(int log_res) 82 { 83 return (log_res * 3 / 4) / XFS_REFCOUNT_ITEM_OVERHEAD; 84 } 85 86 extern int xfs_refcount_has_record(struct xfs_btree_cur *cur, 87 xfs_agblock_t bno, xfs_extlen_t len, bool *exists); 88 89 #endif /* __XFS_REFCOUNT_H__ */ 90