xfs_reflink.h

 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_REFLINK_H
 7#define __XFS_REFLINK_H 1
 8
 9/*
10 * Check whether it is safe to free COW fork blocks from an inode. It is unsafe
11 * to do so when an inode has dirty cache or I/O in-flight, even if no shared
12 * extents exist in the data fork, because outstanding I/O may target blocks
13 * that were speculatively allocated to the COW fork.
14 */
15static inline bool
16xfs_can_free_cowblocks(struct xfs_inode *ip)
17{
18	struct inode *inode = VFS_I(ip);
19
20	if ((inode_state_read_once(inode) & I_DIRTY_PAGES) ||
21	    mapping_tagged(inode->i_mapping, PAGECACHE_TAG_DIRTY) ||
22	    mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK) ||
23	    atomic_read(&inode->i_dio_count))
24		return false;
25	return true;
26}
27
28int xfs_reflink_trim_around_shared(struct xfs_inode *ip,
29		struct xfs_bmbt_irec *irec, bool *shared);
30int xfs_bmap_trim_cow(struct xfs_inode *ip, struct xfs_bmbt_irec *imap,
31		bool *shared);
32
33int xfs_reflink_allocate_cow(struct xfs_inode *ip, struct xfs_bmbt_irec *imap,
34		struct xfs_bmbt_irec *cmap, bool *shared, uint *lockmode,
35		bool convert_now);
36extern int xfs_reflink_convert_cow(struct xfs_inode *ip, xfs_off_t offset,
37		xfs_off_t count);
38int xfs_reflink_convert_cow_locked(struct xfs_inode *ip,
39		xfs_fileoff_t offset_fsb, xfs_filblks_t count_fsb);
40
41extern int xfs_reflink_cancel_cow_blocks(struct xfs_inode *ip,
42		struct xfs_trans **tpp, xfs_fileoff_t offset_fsb,
43		xfs_fileoff_t end_fsb, bool cancel_real);
44extern int xfs_reflink_cancel_cow_range(struct xfs_inode *ip, xfs_off_t offset,
45		xfs_off_t count, bool cancel_real);
46extern int xfs_reflink_end_cow(struct xfs_inode *ip, xfs_off_t offset,
47		xfs_off_t count);
48int xfs_reflink_end_atomic_cow(struct xfs_inode *ip, xfs_off_t offset,
49		xfs_off_t count);
50extern int xfs_reflink_recover_cow(struct xfs_mount *mp);
51extern loff_t xfs_reflink_remap_range(struct file *file_in, loff_t pos_in,
52		struct file *file_out, loff_t pos_out, loff_t len,
53		unsigned int remap_flags);
54extern int xfs_reflink_inode_has_shared_extents(struct xfs_trans *tp,
55		struct xfs_inode *ip, bool *has_shared);
56extern int xfs_reflink_clear_inode_flag(struct xfs_inode *ip,
57		struct xfs_trans **tpp);
58extern int xfs_reflink_unshare(struct xfs_inode *ip, xfs_off_t offset,
59		xfs_off_t len);
60extern int xfs_reflink_remap_prep(struct file *file_in, loff_t pos_in,
61		struct file *file_out, loff_t pos_out, loff_t *len,
62		unsigned int remap_flags);
63extern int xfs_reflink_remap_blocks(struct xfs_inode *src, loff_t pos_in,
64		struct xfs_inode *dest, loff_t pos_out, loff_t remap_len,
65		loff_t *remapped);
66extern int xfs_reflink_update_dest(struct xfs_inode *dest, xfs_off_t newlen,
67		xfs_extlen_t cowextsize, unsigned int remap_flags);
68
69bool xfs_reflink_supports_rextsize(struct xfs_mount *mp, unsigned int rextsize);
70
71xfs_extlen_t xfs_reflink_max_atomic_cow(struct xfs_mount *mp);
72
73#endif /* __XFS_REFLINK_H */