1 files changed, 73 insertions, 0 deletions
diff --git a/fs/xfs/xfs_reflink.h b/fs/xfs/xfs_reflink.h
new file mode 100644
index 000000000000..9d1ed9bb0bee
--- /dev/null
+++ b/fs/xfs/xfs_reflink.h
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2016 Oracle.  All Rights Reserved.
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ */
+#ifndef __XFS_REFLINK_H
+#define __XFS_REFLINK_H 1
+
+/*
+ * Check whether it is safe to free COW fork blocks from an inode. It is unsafe
+ * to do so when an inode has dirty cache or I/O in-flight, even if no shared
+ * extents exist in the data fork, because outstanding I/O may target blocks
+ * that were speculatively allocated to the COW fork.
+ */
+static inline bool
+xfs_can_free_cowblocks(struct xfs_inode *ip)
+{
+	struct inode *inode = VFS_I(ip);
+
+	if ((inode_state_read_once(inode) & I_DIRTY_PAGES) ||
+	    mapping_tagged(inode->i_mapping, PAGECACHE_TAG_DIRTY) ||
+	    mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK) ||
+	    atomic_read(&inode->i_dio_count))
+		return false;
+	return true;
+}
+
+int xfs_reflink_trim_around_shared(struct xfs_inode *ip,
+		struct xfs_bmbt_irec *irec, bool *shared);
+int xfs_bmap_trim_cow(struct xfs_inode *ip, struct xfs_bmbt_irec *imap,
+		bool *shared);
+
+int xfs_reflink_allocate_cow(struct xfs_inode *ip, struct xfs_bmbt_irec *imap,
+		struct xfs_bmbt_irec *cmap, bool *shared, uint *lockmode,
+		bool convert_now);
+extern int xfs_reflink_convert_cow(struct xfs_inode *ip, xfs_off_t offset,
+		xfs_off_t count);
+int xfs_reflink_convert_cow_locked(struct xfs_inode *ip,
+		xfs_fileoff_t offset_fsb, xfs_filblks_t count_fsb);
+
+extern int xfs_reflink_cancel_cow_blocks(struct xfs_inode *ip,
+		struct xfs_trans **tpp, xfs_fileoff_t offset_fsb,
+		xfs_fileoff_t end_fsb, bool cancel_real);
+extern int xfs_reflink_cancel_cow_range(struct xfs_inode *ip, xfs_off_t offset,
+		xfs_off_t count, bool cancel_real);
+extern int xfs_reflink_end_cow(struct xfs_inode *ip, xfs_off_t offset,
+		xfs_off_t count);
+int xfs_reflink_end_atomic_cow(struct xfs_inode *ip, xfs_off_t offset,
+		xfs_off_t count);
+extern int xfs_reflink_recover_cow(struct xfs_mount *mp);
+extern loff_t xfs_reflink_remap_range(struct file *file_in, loff_t pos_in,
+		struct file *file_out, loff_t pos_out, loff_t len,
+		unsigned int remap_flags);
+extern int xfs_reflink_inode_has_shared_extents(struct xfs_trans *tp,
+		struct xfs_inode *ip, bool *has_shared);
+extern int xfs_reflink_clear_inode_flag(struct xfs_inode *ip,
+		struct xfs_trans **tpp);
+extern int xfs_reflink_unshare(struct xfs_inode *ip, xfs_off_t offset,
+		xfs_off_t len);
+extern int xfs_reflink_remap_prep(struct file *file_in, loff_t pos_in,
+		struct file *file_out, loff_t pos_out, loff_t *len,
+		unsigned int remap_flags);
+extern int xfs_reflink_remap_blocks(struct xfs_inode *src, loff_t pos_in,
+		struct xfs_inode *dest, loff_t pos_out, loff_t remap_len,
+		loff_t *remapped);
+extern int xfs_reflink_update_dest(struct xfs_inode *dest, xfs_off_t newlen,
+		xfs_extlen_t cowextsize, unsigned int remap_flags);
+
+bool xfs_reflink_supports_rextsize(struct xfs_mount *mp, unsigned int rextsize);
+
+xfs_extlen_t xfs_reflink_max_atomic_cow(struct xfs_mount *mp);
+
+#endif /* __XFS_REFLINK_H */