| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Copyright (C) 2016 Oracle. All Rights Reserved. |
| * Author: Darrick J. Wong <darrick.wong@oracle.com> |
| */ |
| #ifndef __XFS_REFCOUNT_H__ |
| #define __XFS_REFCOUNT_H__ |
| |
| struct xfs_trans; |
| struct xfs_mount; |
| struct xfs_perag; |
| struct xfs_btree_cur; |
| struct xfs_bmbt_irec; |
| struct xfs_refcount_irec; |
| |
| extern int xfs_refcount_lookup_le(struct xfs_btree_cur *cur, |
| enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat); |
| extern int xfs_refcount_lookup_ge(struct xfs_btree_cur *cur, |
| enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat); |
| extern int xfs_refcount_lookup_eq(struct xfs_btree_cur *cur, |
| enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat); |
| extern int xfs_refcount_get_rec(struct xfs_btree_cur *cur, |
| struct xfs_refcount_irec *irec, int *stat); |
| |
| static inline uint32_t |
| xfs_refcount_encode_startblock( |
| xfs_agblock_t startblock, |
| enum xfs_refc_domain domain) |
| { |
| uint32_t start; |
| |
| /* |
| * low level btree operations need to handle the generic btree range |
| * query functions (which set rc_domain == -1U), so we check that the |
| * domain is /not/ shared. |
| */ |
| start = startblock & ~XFS_REFC_COWFLAG; |
| if (domain != XFS_REFC_DOMAIN_SHARED) |
| start |= XFS_REFC_COWFLAG; |
| |
| return start; |
| } |
| |
| enum xfs_refcount_intent_type { |
| XFS_REFCOUNT_INCREASE = 1, |
| XFS_REFCOUNT_DECREASE, |
| XFS_REFCOUNT_ALLOC_COW, |
| XFS_REFCOUNT_FREE_COW, |
| }; |
| |
| struct xfs_refcount_intent { |
| struct list_head ri_list; |
| struct xfs_perag *ri_pag; |
| enum xfs_refcount_intent_type ri_type; |
| xfs_extlen_t ri_blockcount; |
| xfs_fsblock_t ri_startblock; |
| }; |
| |
| /* Check that the refcount is appropriate for the record domain. */ |
| static inline bool |
| xfs_refcount_check_domain( |
| const struct xfs_refcount_irec *irec) |
| { |
| if (irec->rc_domain == XFS_REFC_DOMAIN_COW && irec->rc_refcount != 1) |
| return false; |
| if (irec->rc_domain == XFS_REFC_DOMAIN_SHARED && irec->rc_refcount < 2) |
| return false; |
| return true; |
| } |
| |
| void xfs_refcount_update_get_group(struct xfs_mount *mp, |
| struct xfs_refcount_intent *ri); |
| |
| void xfs_refcount_increase_extent(struct xfs_trans *tp, |
| struct xfs_bmbt_irec *irec); |
| void xfs_refcount_decrease_extent(struct xfs_trans *tp, |
| struct xfs_bmbt_irec *irec); |
| |
| extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp, |
| struct xfs_btree_cur *rcur, int error); |
| extern int xfs_refcount_finish_one(struct xfs_trans *tp, |
| struct xfs_refcount_intent *ri, struct xfs_btree_cur **pcur); |
| |
| extern int xfs_refcount_find_shared(struct xfs_btree_cur *cur, |
| xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno, |
| xfs_extlen_t *flen, bool find_end_of_shared); |
| |
| void xfs_refcount_alloc_cow_extent(struct xfs_trans *tp, xfs_fsblock_t fsb, |
| xfs_extlen_t len); |
| void xfs_refcount_free_cow_extent(struct xfs_trans *tp, xfs_fsblock_t fsb, |
| xfs_extlen_t len); |
| extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp, |
| struct xfs_perag *pag); |
| |
| /* |
| * While we're adjusting the refcounts records of an extent, we have |
| * to keep an eye on the number of extents we're dirtying -- run too |
| * many in a single transaction and we'll exceed the transaction's |
| * reservation and crash the fs. Each record adds 12 bytes to the |
| * log (plus any key updates) so we'll conservatively assume 32 bytes |
| * per record. We must also leave space for btree splits on both ends |
| * of the range and space for the CUD and a new CUI. |
| * |
| * Each EFI that we attach to the transaction is assumed to consume ~32 bytes. |
| * This is a low estimate for an EFI tracking a single extent (16 bytes for the |
| * EFI header, 16 for the extent, and 12 for the xlog op header), but the |
| * estimate is acceptable if there's more than one extent being freed. |
| * In the worst case of freeing every other block during a refcount decrease |
| * operation, we amortize the space used for one EFI log item across 16 |
| * extents. |
| */ |
| #define XFS_REFCOUNT_ITEM_OVERHEAD 32 |
| |
| extern int xfs_refcount_has_records(struct xfs_btree_cur *cur, |
| enum xfs_refc_domain domain, xfs_agblock_t bno, |
| xfs_extlen_t len, enum xbtree_recpacking *outcome); |
| union xfs_btree_rec; |
| extern void xfs_refcount_btrec_to_irec(const union xfs_btree_rec *rec, |
| struct xfs_refcount_irec *irec); |
| xfs_failaddr_t xfs_refcount_check_irec(struct xfs_perag *pag, |
| const struct xfs_refcount_irec *irec); |
| extern int xfs_refcount_insert(struct xfs_btree_cur *cur, |
| struct xfs_refcount_irec *irec, int *stat); |
| |
| extern struct kmem_cache *xfs_refcount_intent_cache; |
| |
| int __init xfs_refcount_intent_init_cache(void); |
| void xfs_refcount_intent_destroy_cache(void); |
| |
| typedef int (*xfs_refcount_query_range_fn)( |
| struct xfs_btree_cur *cur, |
| const struct xfs_refcount_irec *rec, |
| void *priv); |
| |
| int xfs_refcount_query_range(struct xfs_btree_cur *cur, |
| const struct xfs_refcount_irec *low_rec, |
| const struct xfs_refcount_irec *high_rec, |
| xfs_refcount_query_range_fn fn, void *priv); |
| |
| #endif /* __XFS_REFCOUNT_H__ */ |