1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-or-later */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * runlist.h - Defines for runlist handling in NTFS Linux kernel driver.
4*4882a593Smuzhiyun * Part of the Linux-NTFS project.
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * Copyright (c) 2001-2005 Anton Altaparmakov
7*4882a593Smuzhiyun * Copyright (c) 2002 Richard Russon
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #ifndef _LINUX_NTFS_RUNLIST_H
11*4882a593Smuzhiyun #define _LINUX_NTFS_RUNLIST_H
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun #include "types.h"
14*4882a593Smuzhiyun #include "layout.h"
15*4882a593Smuzhiyun #include "volume.h"
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun /**
18*4882a593Smuzhiyun * runlist_element - in memory vcn to lcn mapping array element
19*4882a593Smuzhiyun * @vcn: starting vcn of the current array element
20*4882a593Smuzhiyun * @lcn: starting lcn of the current array element
21*4882a593Smuzhiyun * @length: length in clusters of the current array element
22*4882a593Smuzhiyun *
23*4882a593Smuzhiyun * The last vcn (in fact the last vcn + 1) is reached when length == 0.
24*4882a593Smuzhiyun *
25*4882a593Smuzhiyun * When lcn == -1 this means that the count vcns starting at vcn are not
26*4882a593Smuzhiyun * physically allocated (i.e. this is a hole / data is sparse).
27*4882a593Smuzhiyun */
28*4882a593Smuzhiyun typedef struct { /* In memory vcn to lcn mapping structure element. */
29*4882a593Smuzhiyun VCN vcn; /* vcn = Starting virtual cluster number. */
30*4882a593Smuzhiyun LCN lcn; /* lcn = Starting logical cluster number. */
31*4882a593Smuzhiyun s64 length; /* Run length in clusters. */
32*4882a593Smuzhiyun } runlist_element;
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun /**
35*4882a593Smuzhiyun * runlist - in memory vcn to lcn mapping array including a read/write lock
36*4882a593Smuzhiyun * @rl: pointer to an array of runlist elements
37*4882a593Smuzhiyun * @lock: read/write spinlock for serializing access to @rl
38*4882a593Smuzhiyun *
39*4882a593Smuzhiyun */
40*4882a593Smuzhiyun typedef struct {
41*4882a593Smuzhiyun runlist_element *rl;
42*4882a593Smuzhiyun struct rw_semaphore lock;
43*4882a593Smuzhiyun } runlist;
44*4882a593Smuzhiyun
ntfs_init_runlist(runlist * rl)45*4882a593Smuzhiyun static inline void ntfs_init_runlist(runlist *rl)
46*4882a593Smuzhiyun {
47*4882a593Smuzhiyun rl->rl = NULL;
48*4882a593Smuzhiyun init_rwsem(&rl->lock);
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun
51*4882a593Smuzhiyun typedef enum {
52*4882a593Smuzhiyun LCN_HOLE = -1, /* Keep this as highest value or die! */
53*4882a593Smuzhiyun LCN_RL_NOT_MAPPED = -2,
54*4882a593Smuzhiyun LCN_ENOENT = -3,
55*4882a593Smuzhiyun LCN_ENOMEM = -4,
56*4882a593Smuzhiyun LCN_EIO = -5,
57*4882a593Smuzhiyun } LCN_SPECIAL_VALUES;
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun extern runlist_element *ntfs_runlists_merge(runlist_element *drl,
60*4882a593Smuzhiyun runlist_element *srl);
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun extern runlist_element *ntfs_mapping_pairs_decompress(const ntfs_volume *vol,
63*4882a593Smuzhiyun const ATTR_RECORD *attr, runlist_element *old_rl);
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun extern LCN ntfs_rl_vcn_to_lcn(const runlist_element *rl, const VCN vcn);
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun #ifdef NTFS_RW
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun extern runlist_element *ntfs_rl_find_vcn_nolock(runlist_element *rl,
70*4882a593Smuzhiyun const VCN vcn);
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun extern int ntfs_get_size_for_mapping_pairs(const ntfs_volume *vol,
73*4882a593Smuzhiyun const runlist_element *rl, const VCN first_vcn,
74*4882a593Smuzhiyun const VCN last_vcn);
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun extern int ntfs_mapping_pairs_build(const ntfs_volume *vol, s8 *dst,
77*4882a593Smuzhiyun const int dst_len, const runlist_element *rl,
78*4882a593Smuzhiyun const VCN first_vcn, const VCN last_vcn, VCN *const stop_vcn);
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun extern int ntfs_rl_truncate_nolock(const ntfs_volume *vol,
81*4882a593Smuzhiyun runlist *const runlist, const s64 new_length);
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun int ntfs_rl_punch_nolock(const ntfs_volume *vol, runlist *const runlist,
84*4882a593Smuzhiyun const VCN start, const s64 length);
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun #endif /* NTFS_RW */
87*4882a593Smuzhiyun
88*4882a593Smuzhiyun #endif /* _LINUX_NTFS_RUNLIST_H */
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