/* 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 */
