1 files changed, 88 insertions, 0 deletions
diff --git a/fs/ntfs/runlist.h b/fs/ntfs/runlist.h
new file mode 100644
index 000000000..38de0a375
--- /dev/null
+++ b/fs/ntfs/runlist.h
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * runlist.h - Defines for runlist handling in NTFS Linux kernel driver.
+ *	       Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001-2005 Anton Altaparmakov
+ * Copyright (c) 2002 Richard Russon
+ */
+
+#ifndef _LINUX_NTFS_RUNLIST_H
+#define _LINUX_NTFS_RUNLIST_H
+
+#include "types.h"
+#include "layout.h"
+#include "volume.h"
+
+/**
+ * runlist_element - in memory vcn to lcn mapping array element
+ * @vcn:	starting vcn of the current array element
+ * @lcn:	starting lcn of the current array element
+ * @length:	length in clusters of the current array element
+ *
+ * The last vcn (in fact the last vcn + 1) is reached when length == 0.
+ *
+ * When lcn == -1 this means that the count vcns starting at vcn are not
+ * physically allocated (i.e. this is a hole / data is sparse).
+ */
+typedef struct {	/* In memory vcn to lcn mapping structure element. */
+	VCN vcn;	/* vcn = Starting virtual cluster number. */
+	LCN lcn;	/* lcn = Starting logical cluster number. */
+	s64 length;	/* Run length in clusters. */
+} runlist_element;
+
+/**
+ * runlist - in memory vcn to lcn mapping array including a read/write lock
+ * @rl:		pointer to an array of runlist elements
+ * @lock:	read/write spinlock for serializing access to @rl
+ *
+ */
+typedef struct {
+	runlist_element *rl;
+	struct rw_semaphore lock;
+} runlist;
+
+static inline void ntfs_init_runlist(runlist *rl)
+{
+	rl->rl = NULL;
+	init_rwsem(&rl->lock);
+}
+
+typedef enum {
+	LCN_HOLE		= -1,	/* Keep this as highest value or die! */
+	LCN_RL_NOT_MAPPED	= -2,
+	LCN_ENOENT		= -3,
+	LCN_ENOMEM		= -4,
+	LCN_EIO			= -5,
+} LCN_SPECIAL_VALUES;
+
+extern runlist_element *ntfs_runlists_merge(runlist_element *drl,
+		runlist_element *srl);
+
+extern runlist_element *ntfs_mapping_pairs_decompress(const ntfs_volume *vol,
+		const ATTR_RECORD *attr, runlist_element *old_rl);
+
+extern LCN ntfs_rl_vcn_to_lcn(const runlist_element *rl, const VCN vcn);
+
+#ifdef NTFS_RW
+
+extern runlist_element *ntfs_rl_find_vcn_nolock(runlist_element *rl,
+		const VCN vcn);
+
+extern int ntfs_get_size_for_mapping_pairs(const ntfs_volume *vol,
+		const runlist_element *rl, const VCN first_vcn,
+		const VCN last_vcn);
+
+extern int ntfs_mapping_pairs_build(const ntfs_volume *vol, s8 *dst,
+		const int dst_len, const runlist_element *rl,
+		const VCN first_vcn, const VCN last_vcn, VCN *const stop_vcn);
+
+extern int ntfs_rl_truncate_nolock(const ntfs_volume *vol,
+		runlist *const runlist, const s64 new_length);
+
+int ntfs_rl_punch_nolock(const ntfs_volume *vol, runlist *const runlist,
+		const VCN start, const s64 length);
+
+#endif /* NTFS_RW */
+
+#endif /* _LINUX_NTFS_RUNLIST_H */