v4.19.13 snapshot.
diff --git a/fs/xfs/libxfs/xfs_ialloc.h b/fs/xfs/libxfs/xfs_ialloc.h
new file mode 100644
index 0000000..e936b7c
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_ialloc.h
@@ -0,0 +1,172 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000,2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ */
+#ifndef __XFS_IALLOC_H__
+#define	__XFS_IALLOC_H__
+
+struct xfs_buf;
+struct xfs_dinode;
+struct xfs_imap;
+struct xfs_mount;
+struct xfs_trans;
+struct xfs_btree_cur;
+
+/* Move inodes in clusters of this size */
+#define	XFS_INODE_BIG_CLUSTER_SIZE	8192
+
+struct xfs_icluster {
+	bool		deleted;	/* record is deleted */
+	xfs_ino_t	first_ino;	/* first inode number */
+	uint64_t	alloc;		/* inode phys. allocation bitmap for
+					 * sparse chunks */
+};
+
+/* Calculate and return the number of filesystem blocks per inode cluster */
+static inline int
+xfs_icluster_size_fsb(
+	struct xfs_mount	*mp)
+{
+	if (mp->m_sb.sb_blocksize >= mp->m_inode_cluster_size)
+		return 1;
+	return mp->m_inode_cluster_size >> mp->m_sb.sb_blocklog;
+}
+
+/*
+ * Make an inode pointer out of the buffer/offset.
+ */
+static inline struct xfs_dinode *
+xfs_make_iptr(struct xfs_mount *mp, struct xfs_buf *b, int o)
+{
+	return xfs_buf_offset(b, o << (mp)->m_sb.sb_inodelog);
+}
+
+/*
+ * Allocate an inode on disk.
+ * Mode is used to tell whether the new inode will need space, and whether
+ * it is a directory.
+ *
+ * To work within the constraint of one allocation per transaction,
+ * xfs_dialloc() is designed to be called twice if it has to do an
+ * allocation to make more free inodes.  If an inode is
+ * available without an allocation, agbp would be set to the current
+ * agbp and alloc_done set to false.
+ * If an allocation needed to be done, agbp would be set to the
+ * inode header of the allocation group and alloc_done set to true.
+ * The caller should then commit the current transaction and allocate a new
+ * transaction.  xfs_dialloc() should then be called again with
+ * the agbp value returned from the previous call.
+ *
+ * Once we successfully pick an inode its number is returned and the
+ * on-disk data structures are updated.  The inode itself is not read
+ * in, since doing so would break ordering constraints with xfs_reclaim.
+ *
+ * *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
+ */
+int					/* error */
+xfs_dialloc(
+	struct xfs_trans *tp,		/* transaction pointer */
+	xfs_ino_t	parent,		/* parent inode (directory) */
+	umode_t		mode,		/* mode bits for new inode */
+	struct xfs_buf	**agbp,		/* buf for a.g. inode header */
+	xfs_ino_t	*inop);		/* inode number allocated */
+
+/*
+ * Free disk inode.  Carefully avoids touching the incore inode, all
+ * manipulations incore are the caller's responsibility.
+ * The on-disk inode is not changed by this operation, only the
+ * btree (free inode mask) is changed.
+ */
+int					/* error */
+xfs_difree(
+	struct xfs_trans *tp,		/* transaction pointer */
+	xfs_ino_t	inode,		/* inode to be freed */
+	struct xfs_icluster *ifree);	/* cluster info if deleted */
+
+/*
+ * Return the location of the inode in imap, for mapping it into a buffer.
+ */
+int
+xfs_imap(
+	struct xfs_mount *mp,		/* file system mount structure */
+	struct xfs_trans *tp,		/* transaction pointer */
+	xfs_ino_t	ino,		/* inode to locate */
+	struct xfs_imap	*imap,		/* location map structure */
+	uint		flags);		/* flags for inode btree lookup */
+
+/*
+ * Compute and fill in value of m_in_maxlevels.
+ */
+void
+xfs_ialloc_compute_maxlevels(
+	struct xfs_mount *mp);		/* file system mount structure */
+
+/*
+ * Log specified fields for the ag hdr (inode section)
+ */
+void
+xfs_ialloc_log_agi(
+	struct xfs_trans *tp,		/* transaction pointer */
+	struct xfs_buf	*bp,		/* allocation group header buffer */
+	int		fields);	/* bitmask of fields to log */
+
+/*
+ * Read in the allocation group header (inode allocation section)
+ */
+int					/* error */
+xfs_ialloc_read_agi(
+	struct xfs_mount *mp,		/* file system mount structure */
+	struct xfs_trans *tp,		/* transaction pointer */
+	xfs_agnumber_t	agno,		/* allocation group number */
+	struct xfs_buf	**bpp);		/* allocation group hdr buf */
+
+/*
+ * Read in the allocation group header to initialise the per-ag data
+ * in the mount structure
+ */
+int
+xfs_ialloc_pagi_init(
+	struct xfs_mount *mp,		/* file system mount structure */
+	struct xfs_trans *tp,		/* transaction pointer */
+        xfs_agnumber_t  agno);		/* allocation group number */
+
+/*
+ * Lookup a record by ino in the btree given by cur.
+ */
+int xfs_inobt_lookup(struct xfs_btree_cur *cur, xfs_agino_t ino,
+		xfs_lookup_t dir, int *stat);
+
+/*
+ * Get the data from the pointed-to record.
+ */
+int xfs_inobt_get_rec(struct xfs_btree_cur *cur,
+		xfs_inobt_rec_incore_t *rec, int *stat);
+
+/*
+ * Inode chunk initialisation routine
+ */
+int xfs_ialloc_inode_init(struct xfs_mount *mp, struct xfs_trans *tp,
+			  struct list_head *buffer_list, int icount,
+			  xfs_agnumber_t agno, xfs_agblock_t agbno,
+			  xfs_agblock_t length, unsigned int gen);
+
+int xfs_read_agi(struct xfs_mount *mp, struct xfs_trans *tp,
+		xfs_agnumber_t agno, struct xfs_buf **bpp);
+
+union xfs_btree_rec;
+void xfs_inobt_btrec_to_irec(struct xfs_mount *mp, union xfs_btree_rec *rec,
+		struct xfs_inobt_rec_incore *irec);
+int xfs_ialloc_has_inodes_at_extent(struct xfs_btree_cur *cur,
+		xfs_agblock_t bno, xfs_extlen_t len, bool *exists);
+int xfs_ialloc_has_inode_record(struct xfs_btree_cur *cur, xfs_agino_t low,
+		xfs_agino_t high, bool *exists);
+int xfs_ialloc_count_inodes(struct xfs_btree_cur *cur, xfs_agino_t *count,
+		xfs_agino_t *freecount);
+int xfs_inobt_insert_rec(struct xfs_btree_cur *cur, uint16_t holemask,
+		uint8_t count, int32_t freecount, xfs_inofree_t free,
+		int *stat);
+
+int xfs_ialloc_cluster_alignment(struct xfs_mount *mp);
+
+#endif	/* __XFS_IALLOC_H__ */