fs/xfs/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  */
  15 static inline bool
  16 xfs_can_free_cowblocks(struct xfs_inode *ip)
  17 {
  18         struct inode *inode = VFS_I(ip);
  19
  20         if ((inode->i_state & 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
  28 extern int xfs_reflink_trim_around_shared(struct xfs_inode *ip,
  29                 struct xfs_bmbt_irec *irec, bool *shared);
  30 int xfs_bmap_trim_cow(struct xfs_inode *ip, struct xfs_bmbt_irec *imap,
  31                 bool *shared);
  32
  33 int 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);
  36 extern int xfs_reflink_convert_cow(struct xfs_inode *ip, xfs_off_t offset,
  37                 xfs_off_t count);
  38
  39 extern int xfs_reflink_cancel_cow_blocks(struct xfs_inode *ip,
  40                 struct xfs_trans **tpp, xfs_fileoff_t offset_fsb,
  41                 xfs_fileoff_t end_fsb, bool cancel_real);
  42 extern int xfs_reflink_cancel_cow_range(struct xfs_inode *ip, xfs_off_t offset,
  43                 xfs_off_t count, bool cancel_real);
  44 extern int xfs_reflink_end_cow(struct xfs_inode *ip, xfs_off_t offset,
  45                 xfs_off_t count);
  46 extern int xfs_reflink_recover_cow(struct xfs_mount *mp);
  47 extern loff_t xfs_reflink_remap_range(struct file *file_in, loff_t pos_in,
  48                 struct file *file_out, loff_t pos_out, loff_t len,
  49                 unsigned int remap_flags);
  50 extern int xfs_reflink_inode_has_shared_extents(struct xfs_trans *tp,
  51                 struct xfs_inode *ip, bool *has_shared);
  52 extern int xfs_reflink_clear_inode_flag(struct xfs_inode *ip,
  53                 struct xfs_trans **tpp);
  54 extern int xfs_reflink_unshare(struct xfs_inode *ip, xfs_off_t offset,
  55                 xfs_off_t len);
  56 extern int xfs_reflink_remap_prep(struct file *file_in, loff_t pos_in,
  57                 struct file *file_out, loff_t pos_out, loff_t *len,
  58                 unsigned int remap_flags);
  59 extern int xfs_reflink_remap_blocks(struct xfs_inode *src, loff_t pos_in,
  60                 struct xfs_inode *dest, loff_t pos_out, loff_t remap_len,
  61                 loff_t *remapped);
  62 extern int xfs_reflink_update_dest(struct xfs_inode *dest, xfs_off_t newlen,
  63                 xfs_extlen_t cowextsize, unsigned int remap_flags);
  64
  65 #endif /* __XFS_REFLINK_H */