1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | /* |
3 | * runlist.h - Defines for runlist handling in NTFS Linux kernel driver. |
4 | * Part of the Linux-NTFS project. |
5 | * |
6 | * Copyright (c) 2001-2005 Anton Altaparmakov |
7 | * Copyright (c) 2002 Richard Russon |
8 | */ |
9 | |
10 | #ifndef _LINUX_NTFS_RUNLIST_H |
11 | #define _LINUX_NTFS_RUNLIST_H |
12 | |
13 | #include "types.h" |
14 | #include "layout.h" |
15 | #include "volume.h" |
16 | |
17 | /** |
18 | * runlist_element - in memory vcn to lcn mapping array element |
19 | * @vcn: starting vcn of the current array element |
20 | * @lcn: starting lcn of the current array element |
21 | * @length: length in clusters of the current array element |
22 | * |
23 | * The last vcn (in fact the last vcn + 1) is reached when length == 0. |
24 | * |
25 | * When lcn == -1 this means that the count vcns starting at vcn are not |
26 | * physically allocated (i.e. this is a hole / data is sparse). |
27 | */ |
28 | typedef struct { /* In memory vcn to lcn mapping structure element. */ |
29 | VCN vcn; /* vcn = Starting virtual cluster number. */ |
30 | LCN lcn; /* lcn = Starting logical cluster number. */ |
31 | s64 length; /* Run length in clusters. */ |
32 | } runlist_element; |
33 | |
34 | /** |
35 | * runlist - in memory vcn to lcn mapping array including a read/write lock |
36 | * @rl: pointer to an array of runlist elements |
37 | * @lock: read/write spinlock for serializing access to @rl |
38 | * |
39 | */ |
40 | typedef struct { |
41 | runlist_element *rl; |
42 | struct rw_semaphore lock; |
43 | } runlist; |
44 | |
45 | static inline void ntfs_init_runlist(runlist *rl) |
46 | { |
47 | rl->rl = NULL; |
48 | init_rwsem(&rl->lock); |
49 | } |
50 | |
51 | typedef enum { |
52 | LCN_HOLE = -1, /* Keep this as highest value or die! */ |
53 | LCN_RL_NOT_MAPPED = -2, |
54 | LCN_ENOENT = -3, |
55 | LCN_ENOMEM = -4, |
56 | LCN_EIO = -5, |
57 | } LCN_SPECIAL_VALUES; |
58 | |
59 | extern runlist_element *ntfs_runlists_merge(runlist_element *drl, |
60 | runlist_element *srl); |
61 | |
62 | extern runlist_element *ntfs_mapping_pairs_decompress(const ntfs_volume *vol, |
63 | const ATTR_RECORD *attr, runlist_element *old_rl); |
64 | |
65 | extern LCN ntfs_rl_vcn_to_lcn(const runlist_element *rl, const VCN vcn); |
66 | |
67 | #ifdef NTFS_RW |
68 | |
69 | extern runlist_element *ntfs_rl_find_vcn_nolock(runlist_element *rl, |
70 | const VCN vcn); |
71 | |
72 | extern int ntfs_get_size_for_mapping_pairs(const ntfs_volume *vol, |
73 | const runlist_element *rl, const VCN first_vcn, |
74 | const VCN last_vcn); |
75 | |
76 | extern int ntfs_mapping_pairs_build(const ntfs_volume *vol, s8 *dst, |
77 | const int dst_len, const runlist_element *rl, |
78 | const VCN first_vcn, const VCN last_vcn, VCN *const stop_vcn); |
79 | |
80 | extern int ntfs_rl_truncate_nolock(const ntfs_volume *vol, |
81 | runlist *const runlist, const s64 new_length); |
82 | |
83 | int ntfs_rl_punch_nolock(const ntfs_volume *vol, runlist *const runlist, |
84 | const VCN start, const s64 length); |
85 | |
86 | #endif /* NTFS_RW */ |
87 | |
88 | #endif /* _LINUX_NTFS_RUNLIST_H */ |
89 | |