1 files changed, 268 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_inode_fork.h b/fs/xfs/libxfs/xfs_inode_fork.h
new file mode 100644
index 000000000..d3943d6ad
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_inode_fork.h
@@ -0,0 +1,268 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ */
+#ifndef	__XFS_INODE_FORK_H__
+#define	__XFS_INODE_FORK_H__
+
+struct xfs_inode_log_item;
+struct xfs_dinode;
+
+/*
+ * File incore extent information, present for each of data & attr forks.
+ */
+struct xfs_ifork {
+	int64_t			if_bytes;	/* bytes in if_u1 */
+	struct xfs_btree_block	*if_broot;	/* file's incore btree root */
+	unsigned int		if_seq;		/* fork mod counter */
+	int			if_height;	/* height of the extent tree */
+	union {
+		void		*if_root;	/* extent tree root */
+		char		*if_data;	/* inline file data */
+	} if_u1;
+	xfs_extnum_t		if_nextents;	/* # of extents in this fork */
+	short			if_broot_bytes;	/* bytes allocated for root */
+	int8_t			if_format;	/* format of this fork */
+};
+
+/*
+ * Worst-case increase in the fork extent count when we're adding a single
+ * extent to a fork and there's no possibility of splitting an existing mapping.
+ */
+#define XFS_IEXT_ADD_NOSPLIT_CNT	(1)
+
+/*
+ * Punching out an extent from the middle of an existing extent can cause the
+ * extent count to increase by 1.
+ * i.e. | Old extent | Hole | Old extent |
+ */
+#define XFS_IEXT_PUNCH_HOLE_CNT		(1)
+
+/*
+ * Adding/removing an xattr can cause XFS_DA_NODE_MAXDEPTH extents to
+ * be added. One extra extent for dabtree in case a local attr is
+ * large enough to cause a double split.  It can also cause extent
+ * count to increase proportional to the size of a remote xattr's
+ * value.
+ */
+#define XFS_IEXT_ATTR_MANIP_CNT(rmt_blks) \
+	(XFS_DA_NODE_MAXDEPTH + max(1, rmt_blks))
+
+/*
+ * A write to a sub-interval of an existing unwritten extent causes the original
+ * extent to be split into 3 extents
+ * i.e. | Unwritten | Real | Unwritten |
+ * Hence extent count can increase by 2.
+ */
+#define XFS_IEXT_WRITE_UNWRITTEN_CNT	(2)
+
+
+/*
+ * Moving an extent to data fork can cause a sub-interval of an existing extent
+ * to be unmapped. This will increase extent count by 1. Mapping in the new
+ * extent can increase the extent count by 1 again i.e.
+ * | Old extent | New extent | Old extent |
+ * Hence number of extents increases by 2.
+ */
+#define XFS_IEXT_REFLINK_END_COW_CNT	(2)
+
+/*
+ * Removing an initial range of source/donor file's extent and adding a new
+ * extent (from donor/source file) in its place will cause extent count to
+ * increase by 1.
+ */
+#define XFS_IEXT_SWAP_RMAP_CNT		(1)
+
+/*
+ * Fork handling.
+ */
+#define XFS_IFORK_MAXEXT(ip, w) \
+	(xfs_inode_fork_size(ip, w) / sizeof(xfs_bmbt_rec_t))
+
+static inline bool xfs_ifork_has_extents(struct xfs_ifork *ifp)
+{
+	return ifp->if_format == XFS_DINODE_FMT_EXTENTS ||
+		ifp->if_format == XFS_DINODE_FMT_BTREE;
+}
+
+static inline xfs_extnum_t xfs_ifork_nextents(struct xfs_ifork *ifp)
+{
+	if (!ifp)
+		return 0;
+	return ifp->if_nextents;
+}
+
+static inline int8_t xfs_ifork_format(struct xfs_ifork *ifp)
+{
+	if (!ifp)
+		return XFS_DINODE_FMT_EXTENTS;
+	return ifp->if_format;
+}
+
+static inline xfs_extnum_t xfs_iext_max_nextents(bool has_large_extent_counts,
+				int whichfork)
+{
+	switch (whichfork) {
+	case XFS_DATA_FORK:
+	case XFS_COW_FORK:
+		if (has_large_extent_counts)
+			return XFS_MAX_EXTCNT_DATA_FORK_LARGE;
+		return XFS_MAX_EXTCNT_DATA_FORK_SMALL;
+
+	case XFS_ATTR_FORK:
+		if (has_large_extent_counts)
+			return XFS_MAX_EXTCNT_ATTR_FORK_LARGE;
+		return XFS_MAX_EXTCNT_ATTR_FORK_SMALL;
+
+	default:
+		ASSERT(0);
+		return 0;
+	}
+}
+
+static inline xfs_extnum_t
+xfs_dfork_data_extents(
+	struct xfs_dinode	*dip)
+{
+	if (xfs_dinode_has_large_extent_counts(dip))
+		return be64_to_cpu(dip->di_big_nextents);
+
+	return be32_to_cpu(dip->di_nextents);
+}
+
+static inline xfs_extnum_t
+xfs_dfork_attr_extents(
+	struct xfs_dinode	*dip)
+{
+	if (xfs_dinode_has_large_extent_counts(dip))
+		return be32_to_cpu(dip->di_big_anextents);
+
+	return be16_to_cpu(dip->di_anextents);
+}
+
+static inline xfs_extnum_t
+xfs_dfork_nextents(
+	struct xfs_dinode	*dip,
+	int			whichfork)
+{
+	switch (whichfork) {
+	case XFS_DATA_FORK:
+		return xfs_dfork_data_extents(dip);
+	case XFS_ATTR_FORK:
+		return xfs_dfork_attr_extents(dip);
+	default:
+		ASSERT(0);
+		break;
+	}
+
+	return 0;
+}
+
+void xfs_ifork_zap_attr(struct xfs_inode *ip);
+void xfs_ifork_init_attr(struct xfs_inode *ip, enum xfs_dinode_fmt format,
+		xfs_extnum_t nextents);
+struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state);
+
+int		xfs_iformat_data_fork(struct xfs_inode *, struct xfs_dinode *);
+int		xfs_iformat_attr_fork(struct xfs_inode *, struct xfs_dinode *);
+void		xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
+				struct xfs_inode_log_item *, int);
+void		xfs_idestroy_fork(struct xfs_ifork *ifp);
+void		xfs_idata_realloc(struct xfs_inode *ip, int64_t byte_diff,
+				int whichfork);
+void		xfs_iroot_realloc(struct xfs_inode *, int, int);
+int		xfs_iread_extents(struct xfs_trans *, struct xfs_inode *, int);
+int		xfs_iextents_copy(struct xfs_inode *, struct xfs_bmbt_rec *,
+				  int);
+void		xfs_init_local_fork(struct xfs_inode *ip, int whichfork,
+				const void *data, int64_t size);
+
+xfs_extnum_t	xfs_iext_count(struct xfs_ifork *ifp);
+void		xfs_iext_insert(struct xfs_inode *, struct xfs_iext_cursor *cur,
+			struct xfs_bmbt_irec *, int);
+void		xfs_iext_remove(struct xfs_inode *, struct xfs_iext_cursor *,
+			int);
+void		xfs_iext_destroy(struct xfs_ifork *);
+
+bool		xfs_iext_lookup_extent(struct xfs_inode *ip,
+			struct xfs_ifork *ifp, xfs_fileoff_t bno,
+			struct xfs_iext_cursor *cur,
+			struct xfs_bmbt_irec *gotp);
+bool		xfs_iext_lookup_extent_before(struct xfs_inode *ip,
+			struct xfs_ifork *ifp, xfs_fileoff_t *end,
+			struct xfs_iext_cursor *cur,
+			struct xfs_bmbt_irec *gotp);
+bool		xfs_iext_get_extent(struct xfs_ifork *ifp,
+			struct xfs_iext_cursor *cur,
+			struct xfs_bmbt_irec *gotp);
+void		xfs_iext_update_extent(struct xfs_inode *ip, int state,
+			struct xfs_iext_cursor *cur,
+			struct xfs_bmbt_irec *gotp);
+
+void		xfs_iext_first(struct xfs_ifork *, struct xfs_iext_cursor *);
+void		xfs_iext_last(struct xfs_ifork *, struct xfs_iext_cursor *);
+void		xfs_iext_next(struct xfs_ifork *, struct xfs_iext_cursor *);
+void		xfs_iext_prev(struct xfs_ifork *, struct xfs_iext_cursor *);
+
+static inline bool xfs_iext_next_extent(struct xfs_ifork *ifp,
+		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
+{
+	xfs_iext_next(ifp, cur);
+	return xfs_iext_get_extent(ifp, cur, gotp);
+}
+
+static inline bool xfs_iext_prev_extent(struct xfs_ifork *ifp,
+		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
+{
+	xfs_iext_prev(ifp, cur);
+	return xfs_iext_get_extent(ifp, cur, gotp);
+}
+
+/*
+ * Return the extent after cur in gotp without updating the cursor.
+ */
+static inline bool xfs_iext_peek_next_extent(struct xfs_ifork *ifp,
+		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
+{
+	struct xfs_iext_cursor ncur = *cur;
+
+	xfs_iext_next(ifp, &ncur);
+	return xfs_iext_get_extent(ifp, &ncur, gotp);
+}
+
+/*
+ * Return the extent before cur in gotp without updating the cursor.
+ */
+static inline bool xfs_iext_peek_prev_extent(struct xfs_ifork *ifp,
+		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
+{
+	struct xfs_iext_cursor ncur = *cur;
+
+	xfs_iext_prev(ifp, &ncur);
+	return xfs_iext_get_extent(ifp, &ncur, gotp);
+}
+
+#define for_each_xfs_iext(ifp, ext, got)		\
+	for (xfs_iext_first((ifp), (ext));		\
+	     xfs_iext_get_extent((ifp), (ext), (got));	\
+	     xfs_iext_next((ifp), (ext)))
+
+extern struct kmem_cache	*xfs_ifork_cache;
+
+extern void xfs_ifork_init_cow(struct xfs_inode *ip);
+
+int xfs_ifork_verify_local_data(struct xfs_inode *ip);
+int xfs_ifork_verify_local_attr(struct xfs_inode *ip);
+int xfs_iext_count_may_overflow(struct xfs_inode *ip, int whichfork,
+		int nr_to_add);
+int xfs_iext_count_upgrade(struct xfs_trans *tp, struct xfs_inode *ip,
+		uint nr_to_add);
+
+/* returns true if the fork has extents but they are not read in yet. */
+static inline bool xfs_need_iread_extents(struct xfs_ifork *ifp)
+{
+	return ifp->if_format == XFS_DINODE_FMT_BTREE && ifp->if_height == 0;
+}
+
+#endif	/* __XFS_INODE_FORK_H__ */