xref: /openbmc/linux/fs/ntfs/inode.h (revision b868a02e)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * inode.h - Defines for inode structures NTFS Linux kernel driver. Part of
4  *	     the Linux-NTFS project.
5  *
6  * Copyright (c) 2001-2007 Anton Altaparmakov
7  * Copyright (c) 2002 Richard Russon
8  */
9 
10 #ifndef _LINUX_NTFS_INODE_H
11 #define _LINUX_NTFS_INODE_H
12 
13 #include <linux/atomic.h>
14 
15 #include <linux/fs.h>
16 #include <linux/list.h>
17 #include <linux/mm.h>
18 #include <linux/mutex.h>
19 #include <linux/seq_file.h>
20 
21 #include "layout.h"
22 #include "volume.h"
23 #include "types.h"
24 #include "runlist.h"
25 #include "debug.h"
26 
27 typedef struct _ntfs_inode ntfs_inode;
28 
29 /*
30  * The NTFS in-memory inode structure. It is just used as an extension to the
31  * fields already provided in the VFS inode.
32  */
33 struct _ntfs_inode {
34 	rwlock_t size_lock;	/* Lock serializing access to inode sizes. */
35 	s64 initialized_size;	/* Copy from the attribute record. */
36 	s64 allocated_size;	/* Copy from the attribute record. */
37 	unsigned long state;	/* NTFS specific flags describing this inode.
38 				   See ntfs_inode_state_bits below. */
39 	unsigned long mft_no;	/* Number of the mft record / inode. */
40 	u16 seq_no;		/* Sequence number of the mft record. */
41 	atomic_t count;		/* Inode reference count for book keeping. */
42 	ntfs_volume *vol;	/* Pointer to the ntfs volume of this inode. */
43 	/*
44 	 * If NInoAttr() is true, the below fields describe the attribute which
45 	 * this fake inode belongs to. The actual inode of this attribute is
46 	 * pointed to by base_ntfs_ino and nr_extents is always set to -1 (see
47 	 * below). For real inodes, we also set the type (AT_DATA for files and
48 	 * AT_INDEX_ALLOCATION for directories), with the name = NULL and
49 	 * name_len = 0 for files and name = I30 (global constant) and
50 	 * name_len = 4 for directories.
51 	 */
52 	ATTR_TYPE type;	/* Attribute type of this fake inode. */
53 	ntfschar *name;		/* Attribute name of this fake inode. */
54 	u32 name_len;		/* Attribute name length of this fake inode. */
55 	runlist runlist;	/* If state has the NI_NonResident bit set,
56 				   the runlist of the unnamed data attribute
57 				   (if a file) or of the index allocation
58 				   attribute (directory) or of the attribute
59 				   described by the fake inode (if NInoAttr()).
60 				   If runlist.rl is NULL, the runlist has not
61 				   been read in yet or has been unmapped. If
62 				   NI_NonResident is clear, the attribute is
63 				   resident (file and fake inode) or there is
64 				   no $I30 index allocation attribute
65 				   (small directory). In the latter case
66 				   runlist.rl is always NULL.*/
67 	/*
68 	 * The following fields are only valid for real inodes and extent
69 	 * inodes.
70 	 */
71 	struct mutex mrec_lock;	/* Lock for serializing access to the
72 				   mft record belonging to this inode. */
73 	struct page *page;	/* The page containing the mft record of the
74 				   inode. This should only be touched by the
75 				   (un)map_mft_record*() functions. */
76 	int page_ofs;		/* Offset into the page at which the mft record
77 				   begins. This should only be touched by the
78 				   (un)map_mft_record*() functions. */
79 	/*
80 	 * Attribute list support (only for use by the attribute lookup
81 	 * functions). Setup during read_inode for all inodes with attribute
82 	 * lists. Only valid if NI_AttrList is set in state, and attr_list_rl is
83 	 * further only valid if NI_AttrListNonResident is set.
84 	 */
85 	u32 attr_list_size;	/* Length of attribute list value in bytes. */
86 	u8 *attr_list;		/* Attribute list value itself. */
87 	runlist attr_list_rl;	/* Run list for the attribute list value. */
88 	union {
89 		struct { /* It is a directory, $MFT, or an index inode. */
90 			u32 block_size;		/* Size of an index block. */
91 			u32 vcn_size;		/* Size of a vcn in this
92 						   index. */
93 			COLLATION_RULE collation_rule; /* The collation rule
94 						   for the index. */
95 			u8 block_size_bits; 	/* Log2 of the above. */
96 			u8 vcn_size_bits;	/* Log2 of the above. */
97 		} index;
98 		struct { /* It is a compressed/sparse file/attribute inode. */
99 			s64 size;		/* Copy of compressed_size from
100 						   $DATA. */
101 			u32 block_size;		/* Size of a compression block
102 						   (cb). */
103 			u8 block_size_bits;	/* Log2 of the size of a cb. */
104 			u8 block_clusters;	/* Number of clusters per cb. */
105 		} compressed;
106 	} itype;
107 	struct mutex extent_lock;	/* Lock for accessing/modifying the
108 					   below . */
109 	s32 nr_extents;	/* For a base mft record, the number of attached extent
110 			   inodes (0 if none), for extent records and for fake
111 			   inodes describing an attribute this is -1. */
112 	union {		/* This union is only used if nr_extents != 0. */
113 		ntfs_inode **extent_ntfs_inos;	/* For nr_extents > 0, array of
114 						   the ntfs inodes of the extent
115 						   mft records belonging to
116 						   this base inode which have
117 						   been loaded. */
118 		ntfs_inode *base_ntfs_ino;	/* For nr_extents == -1, the
119 						   ntfs inode of the base mft
120 						   record. For fake inodes, the
121 						   real (base) inode to which
122 						   the attribute belongs. */
123 	} ext;
124 };
125 
126 /*
127  * Defined bits for the state field in the ntfs_inode structure.
128  * (f) = files only, (d) = directories only, (a) = attributes/fake inodes only
129  */
130 typedef enum {
131 	NI_Dirty,		/* 1: Mft record needs to be written to disk. */
132 	NI_AttrList,		/* 1: Mft record contains an attribute list. */
133 	NI_AttrListNonResident,	/* 1: Attribute list is non-resident. Implies
134 				      NI_AttrList is set. */
135 
136 	NI_Attr,		/* 1: Fake inode for attribute i/o.
137 				   0: Real inode or extent inode. */
138 
139 	NI_MstProtected,	/* 1: Attribute is protected by MST fixups.
140 				   0: Attribute is not protected by fixups. */
141 	NI_NonResident,		/* 1: Unnamed data attr is non-resident (f).
142 				   1: Attribute is non-resident (a). */
143 	NI_IndexAllocPresent = NI_NonResident,	/* 1: $I30 index alloc attr is
144 						   present (d). */
145 	NI_Compressed,		/* 1: Unnamed data attr is compressed (f).
146 				   1: Create compressed files by default (d).
147 				   1: Attribute is compressed (a). */
148 	NI_Encrypted,		/* 1: Unnamed data attr is encrypted (f).
149 				   1: Create encrypted files by default (d).
150 				   1: Attribute is encrypted (a). */
151 	NI_Sparse,		/* 1: Unnamed data attr is sparse (f).
152 				   1: Create sparse files by default (d).
153 				   1: Attribute is sparse (a). */
154 	NI_SparseDisabled,	/* 1: May not create sparse regions. */
155 	NI_TruncateFailed,	/* 1: Last ntfs_truncate() call failed. */
156 } ntfs_inode_state_bits;
157 
158 /*
159  * NOTE: We should be adding dirty mft records to a list somewhere and they
160  * should be independent of the (ntfs/vfs) inode structure so that an inode can
161  * be removed but the record can be left dirty for syncing later.
162  */
163 
164 /*
165  * Macro tricks to expand the NInoFoo(), NInoSetFoo(), and NInoClearFoo()
166  * functions.
167  */
168 #define NINO_FNS(flag)					\
169 static inline int NIno##flag(ntfs_inode *ni)		\
170 {							\
171 	return test_bit(NI_##flag, &(ni)->state);	\
172 }							\
173 static inline void NInoSet##flag(ntfs_inode *ni)	\
174 {							\
175 	set_bit(NI_##flag, &(ni)->state);		\
176 }							\
177 static inline void NInoClear##flag(ntfs_inode *ni)	\
178 {							\
179 	clear_bit(NI_##flag, &(ni)->state);		\
180 }
181 
182 /*
183  * As above for NInoTestSetFoo() and NInoTestClearFoo().
184  */
185 #define TAS_NINO_FNS(flag)					\
186 static inline int NInoTestSet##flag(ntfs_inode *ni)		\
187 {								\
188 	return test_and_set_bit(NI_##flag, &(ni)->state);	\
189 }								\
190 static inline int NInoTestClear##flag(ntfs_inode *ni)		\
191 {								\
192 	return test_and_clear_bit(NI_##flag, &(ni)->state);	\
193 }
194 
195 /* Emit the ntfs inode bitops functions. */
196 NINO_FNS(Dirty)
197 TAS_NINO_FNS(Dirty)
198 NINO_FNS(AttrList)
199 NINO_FNS(AttrListNonResident)
200 NINO_FNS(Attr)
201 NINO_FNS(MstProtected)
202 NINO_FNS(NonResident)
203 NINO_FNS(IndexAllocPresent)
204 NINO_FNS(Compressed)
205 NINO_FNS(Encrypted)
206 NINO_FNS(Sparse)
207 NINO_FNS(SparseDisabled)
208 NINO_FNS(TruncateFailed)
209 
210 /*
211  * The full structure containing a ntfs_inode and a vfs struct inode. Used for
212  * all real and fake inodes but not for extent inodes which lack the vfs struct
213  * inode.
214  */
215 typedef struct {
216 	ntfs_inode ntfs_inode;
217 	struct inode vfs_inode;		/* The vfs inode structure. */
218 } big_ntfs_inode;
219 
220 /**
221  * NTFS_I - return the ntfs inode given a vfs inode
222  * @inode:	VFS inode
223  *
224  * NTFS_I() returns the ntfs inode associated with the VFS @inode.
225  */
226 static inline ntfs_inode *NTFS_I(struct inode *inode)
227 {
228 	return (ntfs_inode *)container_of(inode, big_ntfs_inode, vfs_inode);
229 }
230 
231 static inline struct inode *VFS_I(ntfs_inode *ni)
232 {
233 	return &((big_ntfs_inode *)ni)->vfs_inode;
234 }
235 
236 /**
237  * ntfs_attr - ntfs in memory attribute structure
238  * @mft_no:	mft record number of the base mft record of this attribute
239  * @name:	Unicode name of the attribute (NULL if unnamed)
240  * @name_len:	length of @name in Unicode characters (0 if unnamed)
241  * @type:	attribute type (see layout.h)
242  *
243  * This structure exists only to provide a small structure for the
244  * ntfs_{attr_}iget()/ntfs_test_inode()/ntfs_init_locked_inode() mechanism.
245  *
246  * NOTE: Elements are ordered by size to make the structure as compact as
247  * possible on all architectures.
248  */
249 typedef struct {
250 	unsigned long mft_no;
251 	ntfschar *name;
252 	u32 name_len;
253 	ATTR_TYPE type;
254 } ntfs_attr;
255 
256 extern int ntfs_test_inode(struct inode *vi, void *data);
257 
258 extern struct inode *ntfs_iget(struct super_block *sb, unsigned long mft_no);
259 extern struct inode *ntfs_attr_iget(struct inode *base_vi, ATTR_TYPE type,
260 		ntfschar *name, u32 name_len);
261 extern struct inode *ntfs_index_iget(struct inode *base_vi, ntfschar *name,
262 		u32 name_len);
263 
264 extern struct inode *ntfs_alloc_big_inode(struct super_block *sb);
265 extern void ntfs_free_big_inode(struct inode *inode);
266 extern void ntfs_evict_big_inode(struct inode *vi);
267 
268 extern void __ntfs_init_inode(struct super_block *sb, ntfs_inode *ni);
269 
270 static inline void ntfs_init_big_inode(struct inode *vi)
271 {
272 	ntfs_inode *ni = NTFS_I(vi);
273 
274 	ntfs_debug("Entering.");
275 	__ntfs_init_inode(vi->i_sb, ni);
276 	ni->mft_no = vi->i_ino;
277 }
278 
279 extern ntfs_inode *ntfs_new_extent_inode(struct super_block *sb,
280 		unsigned long mft_no);
281 extern void ntfs_clear_extent_inode(ntfs_inode *ni);
282 
283 extern int ntfs_read_inode_mount(struct inode *vi);
284 
285 extern int ntfs_show_options(struct seq_file *sf, struct dentry *root);
286 
287 #ifdef NTFS_RW
288 
289 extern int ntfs_truncate(struct inode *vi);
290 extern void ntfs_truncate_vfs(struct inode *vi);
291 
292 extern int ntfs_setattr(struct user_namespace *mnt_userns,
293 			struct dentry *dentry, struct iattr *attr);
294 
295 extern int __ntfs_write_inode(struct inode *vi, int sync);
296 
297 static inline void ntfs_commit_inode(struct inode *vi)
298 {
299 	if (!is_bad_inode(vi))
300 		__ntfs_write_inode(vi, 1);
301 	return;
302 }
303 
304 #else
305 
306 static inline void ntfs_truncate_vfs(struct inode *vi) {}
307 
308 #endif /* NTFS_RW */
309 
310 #endif /* _LINUX_NTFS_INODE_H */
311