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