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diff --git a/fs/ntfs/runlist.h b/fs/ntfs/runlist.h
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+/*
+ * runlist.h - Defines for runlist handling in NTFS Linux kernel driver.
+ * Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001-2004 Anton Altaparmakov
+ * Copyright (c) 2002 Richard Russon
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#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_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);
+
+extern int ntfs_get_size_for_mapping_pairs(const ntfs_volume *vol,
+ const runlist_element *rl, const VCN start_vcn);
+
+extern int ntfs_mapping_pairs_build(const ntfs_volume *vol, s8 *dst,
+ const int dst_len, const runlist_element *rl,
+ const VCN start_vcn, VCN *const stop_vcn);
+
+extern int ntfs_rl_truncate_nolock(const ntfs_volume *vol,
+ runlist *const runlist, const s64 new_length);
+
+#endif /* _LINUX_NTFS_RUNLIST_H */