xref: /linux/fs/ntfs/index.h (revision cdd4dc3aebeab43a72ce0bc2b5bab6f0a80b97a5)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Defines for NTFS kernel index handling.
4  *
5  * Copyright (c) 2004 Anton Altaparmakov
6  */
7 
8 #ifndef _LINUX_NTFS_INDEX_H
9 #define _LINUX_NTFS_INDEX_H
10 
11 #include <linux/fs.h>
12 
13 #include "attrib.h"
14 #include "mft.h"
15 
16 #define  VCN_INDEX_ROOT_PARENT  ((s64)-2)
17 
18 #define MAX_PARENT_VCN	32
19 
20 /*
21  * @idx_ni:	index inode containing the @entry described by this context
22  * @name:	Unicode name of the indexed attribute
23  *		(usually $I30 for directories)
24  * @name_len:	length of @name in Unicode characters
25  * @entry:	index entry (points into @ir or @ia)
26  * @cr:		creation time of the entry (for sorting/validation)
27  * @data:	index entry data (points into @entry)
28  * @data_len:	length in bytes of @data
29  * @is_in_root:	'true' if @entry is in @ir and 'false' if it is in @ia
30  * @ir:		index root if @is_in_root and NULL otherwise
31  * @actx:	attribute search context if @is_in_root and NULL otherwise
32  * @ib:		index block header (valid when @is_in_root is 'false')
33  * @ia_ni:	index allocation inode (extent inode) for @ia
34  * @parent_pos:	array of parent entry positions in the B-tree nodes
35  * @parent_vcn:	VCNs of parent index blocks in the B-tree traversal
36  * @pindex:	current depth (number of parent nodes) in the traversal
37  *		(maximum is MAX_PARENT_VCN)
38  * @ib_dirty:	true if the current index block (@ia/@ib) was modified
39  * @block_size:	size of index blocks in bytes (from $INDEX_ROOT or $Boot)
40  * @vcn_size_bits: log2(cluster size)
41  * @sync_write:	true if synchronous writeback is requested for this context
42  *
43  * @idx_ni is the index inode this context belongs to.
44  *
45  * @entry is the index entry described by this context.  @data and @data_len
46  * are the index entry data and its length in bytes, respectively.  @data
47  * simply points into @entry.  This is probably what the user is interested in.
48  *
49  * If @is_in_root is 'true', @entry is in the index root attribute @ir described
50  * by the attribute search context @actx and the base inode @base_ni.  @ia and
51  * @page are NULL in this case.
52  *
53  * If @is_in_root is 'false', @entry is in the index allocation attribute and @ia
54  * and @page point to the index allocation block and the mapped, locked page it
55  * is in, respectively.  @ir, @actx and @base_ni are NULL in this case.
56  *
57  * To obtain a context call ntfs_index_ctx_get().
58  *
59  * We use this context to allow ntfs_index_lookup() to return the found index
60  * @entry and its @data without having to allocate a buffer and copy the @entry
61  * and/or its @data into it.
62  *
63  * When finished with the @entry and its @data, call ntfs_index_ctx_put() to
64  * free the context and other associated resources.
65  *
66  * If the index entry was modified, ntfs_index_entry_mark_dirty()
67  * or ntfs_index_entry_write() before the call to ntfs_index_ctx_put() to
68  * ensure that the changes are written to disk.
69  */
70 struct ntfs_index_context {
71 	struct ntfs_inode *idx_ni;
72 	__le16 *name;
73 	u32 name_len;
74 	struct index_entry *entry;
75 	__le32 cr;
76 	void *data;
77 	u16 data_len;
78 	bool is_in_root;
79 	struct index_root *ir;
80 	struct ntfs_attr_search_ctx *actx;
81 	struct index_block *ib;
82 	struct ntfs_inode *ia_ni;
83 	int parent_pos[MAX_PARENT_VCN];
84 	s64 parent_vcn[MAX_PARENT_VCN];
85 	int pindex;
86 	bool ib_dirty;
87 	u32 block_size;
88 	u8 vcn_size_bits;
89 	bool sync_write;
90 };
91 
92 int ntfs_index_entry_inconsistent(struct ntfs_index_context *icx, struct ntfs_volume *vol,
93 		const struct index_entry *ie, __le32 collation_rule, u64 inum);
94 struct ntfs_index_context *ntfs_index_ctx_get(struct ntfs_inode *ni, __le16 *name,
95 		u32 name_len);
96 void ntfs_index_ctx_put(struct ntfs_index_context *ictx);
97 int ntfs_index_lookup(const void *key, const u32 key_len,
98 		struct ntfs_index_context *ictx);
99 
100 void ntfs_index_entry_mark_dirty(struct ntfs_index_context *ictx);
101 int ntfs_index_add_filename(struct ntfs_inode *ni, struct file_name_attr *fn, u64 mref);
102 int ntfs_index_remove(struct ntfs_inode *ni, const void *key, const u32 keylen);
103 struct ntfs_inode *ntfs_ia_open(struct ntfs_index_context *icx, struct ntfs_inode *ni);
104 struct index_entry *ntfs_index_walk_down(struct index_entry *ie, struct ntfs_index_context *ictx);
105 struct index_entry *ntfs_index_next(struct index_entry *ie, struct ntfs_index_context *ictx);
106 int ntfs_index_rm(struct ntfs_index_context *icx);
107 void ntfs_index_ctx_reinit(struct ntfs_index_context *icx);
108 int ntfs_ie_add(struct ntfs_index_context *icx, struct index_entry *ie);
109 int ntfs_icx_ib_sync_write(struct ntfs_index_context *icx);
110 
111 #endif /* _LINUX_NTFS_INDEX_H */
112