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/*

 * 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

 *

 * 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_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 */