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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2020-2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#ifndef __XFS_EXCHMAPS_ITEM_H__
+#define __XFS_EXCHMAPS_ITEM_H__
+
+/*
+ * The file mapping exchange intent item helps us exchange multiple file
+ * mappings between two inode forks. It does this by tracking the range of
+ * file block offsets that still need to be exchanged, and relogs as progress
+ * happens.
+ *
+ * *I items should be recorded in the *first* of a series of rolled
+ * transactions, and the *D items should be recorded in the same transaction
+ * that records the associated bmbt updates.
+ *
+ * Should the system crash after the commit of the first transaction but
+ * before the commit of the final transaction in a series, log recovery will
+ * use the redo information recorded by the intent items to replay the
+ * rest of the mapping exchanges.
+ */
+
+/* kernel only XMI/XMD definitions */
+
+struct xfs_mount;
+struct kmem_cache;
+
+/*
+ * This is the incore file mapping exchange intent log item. It is used to log
+ * the fact that we are exchanging mappings between two files. It is used in
+ * conjunction with the incore file mapping exchange done log item described
+ * below.
+ *
+ * These log items follow the same rules as struct xfs_efi_log_item; see the
+ * comments about that structure (in xfs_extfree_item.h) for more details.
+ */
+struct xfs_xmi_log_item {
+ struct xfs_log_item xmi_item;
+ atomic_t xmi_refcount;
+ struct xfs_xmi_log_format xmi_format;
+};
+
+/*
+ * This is the incore file mapping exchange done log item. It is used to log
+ * the fact that an exchange mentioned in an earlier xmi item have been
+ * performed.
+ */
+struct xfs_xmd_log_item {
+ struct xfs_log_item xmd_item;
+ struct xfs_xmi_log_item *xmd_intent_log_item;
+ struct xfs_xmd_log_format xmd_format;
+};
+
+extern struct kmem_cache *xfs_xmi_cache;
+extern struct kmem_cache *xfs_xmd_cache;
+
+struct xfs_exchmaps_intent;
+
+void xfs_exchmaps_defer_add(struct xfs_trans *tp,
+ struct xfs_exchmaps_intent *xmi);
+
+#endif /* __XFS_EXCHMAPS_ITEM_H__ */