v4.19.13 snapshot.
diff --git a/fs/xfs/libxfs/xfs_shared.h b/fs/xfs/libxfs/xfs_shared.h
new file mode 100644
index 0000000..1c5debe
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_shared.h
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * Copyright (c) 2013 Red Hat, Inc.
+ * All Rights Reserved.
+ */
+#ifndef __XFS_SHARED_H__
+#define __XFS_SHARED_H__
+
+/*
+ * Definitions shared between kernel and userspace that don't fit into any other
+ * header file that is shared with userspace.
+ */
+struct xfs_ifork;
+struct xfs_buf;
+struct xfs_buf_ops;
+struct xfs_mount;
+struct xfs_trans;
+struct xfs_inode;
+
+/*
+ * Buffer verifier operations are widely used, including userspace tools
+ */
+extern const struct xfs_buf_ops xfs_agf_buf_ops;
+extern const struct xfs_buf_ops xfs_agi_buf_ops;
+extern const struct xfs_buf_ops xfs_agf_buf_ops;
+extern const struct xfs_buf_ops xfs_agfl_buf_ops;
+extern const struct xfs_buf_ops xfs_allocbt_buf_ops;
+extern const struct xfs_buf_ops xfs_rmapbt_buf_ops;
+extern const struct xfs_buf_ops xfs_refcountbt_buf_ops;
+extern const struct xfs_buf_ops xfs_attr3_leaf_buf_ops;
+extern const struct xfs_buf_ops xfs_attr3_rmt_buf_ops;
+extern const struct xfs_buf_ops xfs_bmbt_buf_ops;
+extern const struct xfs_buf_ops xfs_da3_node_buf_ops;
+extern const struct xfs_buf_ops xfs_dquot_buf_ops;
+extern const struct xfs_buf_ops xfs_symlink_buf_ops;
+extern const struct xfs_buf_ops xfs_agi_buf_ops;
+extern const struct xfs_buf_ops xfs_inobt_buf_ops;
+extern const struct xfs_buf_ops xfs_inode_buf_ops;
+extern const struct xfs_buf_ops xfs_inode_buf_ra_ops;
+extern const struct xfs_buf_ops xfs_dquot_buf_ops;
+extern const struct xfs_buf_ops xfs_dquot_buf_ra_ops;
+extern const struct xfs_buf_ops xfs_sb_buf_ops;
+extern const struct xfs_buf_ops xfs_sb_quiet_buf_ops;
+extern const struct xfs_buf_ops xfs_symlink_buf_ops;
+extern const struct xfs_buf_ops xfs_rtbuf_ops;
+
+/* log size calculation functions */
+int xfs_log_calc_unit_res(struct xfs_mount *mp, int unit_bytes);
+int xfs_log_calc_minimum_size(struct xfs_mount *);
+
+struct xfs_trans_res;
+void xfs_log_get_max_trans_res(struct xfs_mount *mp,
+ struct xfs_trans_res *max_resp);
+
+/*
+ * Values for t_flags.
+ */
+#define XFS_TRANS_DIRTY 0x01 /* something needs to be logged */
+#define XFS_TRANS_SB_DIRTY 0x02 /* superblock is modified */
+#define XFS_TRANS_PERM_LOG_RES 0x04 /* xact took a permanent log res */
+#define XFS_TRANS_SYNC 0x08 /* make commit synchronous */
+#define XFS_TRANS_DQ_DIRTY 0x10 /* at least one dquot in trx dirty */
+#define XFS_TRANS_RESERVE 0x20 /* OK to use reserved data blocks */
+#define XFS_TRANS_NO_WRITECOUNT 0x40 /* do not elevate SB writecount */
+#define XFS_TRANS_NOFS 0x80 /* pass KM_NOFS to kmem_alloc */
+/*
+ * LOWMODE is used by the allocator to activate the lowspace algorithm - when
+ * free space is running low the extent allocator may choose to allocate an
+ * extent from an AG without leaving sufficient space for a btree split when
+ * inserting the new extent. In this case the allocator will enable the
+ * lowspace algorithm which is supposed to allow further allocations (such as
+ * btree splits and newroots) to allocate from sequential AGs. In order to
+ * avoid locking AGs out of order the lowspace algorithm will start searching
+ * for free space from AG 0. If the correct transaction reservations have been
+ * made then this algorithm will eventually find all the space it needs.
+ */
+#define XFS_TRANS_LOWMODE 0x100 /* allocate in low space mode */
+
+/*
+ * Field values for xfs_trans_mod_sb.
+ */
+#define XFS_TRANS_SB_ICOUNT 0x00000001
+#define XFS_TRANS_SB_IFREE 0x00000002
+#define XFS_TRANS_SB_FDBLOCKS 0x00000004
+#define XFS_TRANS_SB_RES_FDBLOCKS 0x00000008
+#define XFS_TRANS_SB_FREXTENTS 0x00000010
+#define XFS_TRANS_SB_RES_FREXTENTS 0x00000020
+#define XFS_TRANS_SB_DBLOCKS 0x00000040
+#define XFS_TRANS_SB_AGCOUNT 0x00000080
+#define XFS_TRANS_SB_IMAXPCT 0x00000100
+#define XFS_TRANS_SB_REXTSIZE 0x00000200
+#define XFS_TRANS_SB_RBMBLOCKS 0x00000400
+#define XFS_TRANS_SB_RBLOCKS 0x00000800
+#define XFS_TRANS_SB_REXTENTS 0x00001000
+#define XFS_TRANS_SB_REXTSLOG 0x00002000
+
+/*
+ * Here we centralize the specification of XFS meta-data buffer reference count
+ * values. This determines how hard the buffer cache tries to hold onto the
+ * buffer.
+ */
+#define XFS_AGF_REF 4
+#define XFS_AGI_REF 4
+#define XFS_AGFL_REF 3
+#define XFS_INO_BTREE_REF 3
+#define XFS_ALLOC_BTREE_REF 2
+#define XFS_BMAP_BTREE_REF 2
+#define XFS_RMAP_BTREE_REF 2
+#define XFS_DIR_BTREE_REF 2
+#define XFS_INO_REF 2
+#define XFS_ATTR_BTREE_REF 1
+#define XFS_DQUOT_REF 1
+#define XFS_REFC_BTREE_REF 1
+#define XFS_SSB_REF 0
+
+/*
+ * Flags for xfs_trans_ichgtime().
+ */
+#define XFS_ICHGTIME_MOD 0x1 /* data fork modification timestamp */
+#define XFS_ICHGTIME_CHG 0x2 /* inode field change timestamp */
+#define XFS_ICHGTIME_CREATE 0x4 /* inode create timestamp */
+
+
+/*
+ * Symlink decoding/encoding functions
+ */
+int xfs_symlink_blocks(struct xfs_mount *mp, int pathlen);
+int xfs_symlink_hdr_set(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset,
+ uint32_t size, struct xfs_buf *bp);
+bool xfs_symlink_hdr_ok(xfs_ino_t ino, uint32_t offset,
+ uint32_t size, struct xfs_buf *bp);
+void xfs_symlink_local_to_remote(struct xfs_trans *tp, struct xfs_buf *bp,
+ struct xfs_inode *ip, struct xfs_ifork *ifp);
+xfs_failaddr_t xfs_symlink_shortform_verify(struct xfs_inode *ip);
+
+#endif /* __XFS_SHARED_H__ */