xref: /haiku/src/add-ons/kernel/file_systems/fat/dosfs.h (revision b671e9bbdbd10268a042b4f4cc4317ccd03d105e)
1 /*
2 	Copyright 1999-2001, Be Incorporated.   All Rights Reserved.
3 	This file may be used under the terms of the Be Sample Code License.
4 */
5 #ifndef _DOSFS_H_
6 #define _DOSFS_H_
7 
8 
9 #include <KernelExport.h>
10 #include <fs_interface.h>
11 #include <lock.h>
12 
13 
14 //#define DEBUG 1
15 
16 
17 #define	LOCK(l)		recursive_lock_lock(&l);
18 #define	UNLOCK(l)	recursive_lock_unlock(&l);
19 
20 
21 /* Unfortunately, ino_t's are defined as signed. This causes problems with
22  * programs (notably cp) that use the modulo of a ino_t as a
23  * hash function to index an array. This means the high bit of every ino_t
24  * is off-limits. Luckily, FAT32 is actually FAT28, so dosfs can make do with
25  * only 63 bits.
26  */
27 #define ARTIFICIAL_VNID_BITS	(0x6LL << 60)
28 #define DIR_CLUSTER_VNID_BITS	(0x4LL << 60)
29 #define DIR_INDEX_VNID_BITS		0
30 #define INVALID_VNID_BITS_MASK	(0x9LL << 60)
31 
32 #define IS_DIR_CLUSTER_VNID(vnid) \
33 	(((vnid) & ARTIFICIAL_VNID_BITS) == DIR_CLUSTER_VNID_BITS)
34 
35 #define IS_DIR_INDEX_VNID(vnid) \
36 	(((vnid) & ARTIFICIAL_VNID_BITS) == DIR_INDEX_VNID_BITS)
37 
38 #define IS_ARTIFICIAL_VNID(vnid) \
39 	(((vnid) & ARTIFICIAL_VNID_BITS) == ARTIFICIAL_VNID_BITS)
40 
41 #define IS_INVALID_VNID(vnid) \
42 	((!IS_DIR_CLUSTER_VNID((vnid)) && \
43 	  !IS_DIR_INDEX_VNID((vnid)) && \
44 	  !IS_ARTIFICIAL_VNID((vnid))) || \
45 	 ((vnid) & INVALID_VNID_BITS_MASK))
46 
47 #define GENERATE_DIR_INDEX_VNID(dircluster, index) \
48 	(DIR_INDEX_VNID_BITS | ((ino_t)(dircluster) << 32) | (index))
49 
50 #define GENERATE_DIR_CLUSTER_VNID(dircluster, filecluster) \
51 	(DIR_CLUSTER_VNID_BITS | ((ino_t)(dircluster) << 32) | (filecluster))
52 
53 #define CLUSTER_OF_DIR_CLUSTER_VNID(vnid) \
54 	((uint32)((vnid) & 0xffffffff))
55 
56 #define INDEX_OF_DIR_INDEX_VNID(vnid) \
57 	((uint32)((vnid) & 0xffffffff))
58 
59 #define DIR_OF_VNID(vnid) \
60 	((uint32)(((vnid) >> 32) & ~0xf0000000))
61 
62 #define VNODE_PARENT_DIR_CLUSTER(vnode) \
63 	CLUSTER_OF_DIR_CLUSTER_VNID((vnode)->dir_vnid)
64 
65 
66 typedef struct vnode {
67 	ino_t		vnid; 			// self id
68 	ino_t	 	dir_vnid;		// parent vnode id (directory containing entry)
69 	void		*cache;
70 	void		*file_map;
71 
72 	uint32		disk_image;		// 0 = no, 1 = BEOS, 2 = IMAGE.BE
73 
74 	/* iteration is incremented each time the fat chain changes. it's used by
75 	 * the file read/write code to determine if it needs to retraverse the
76 	 * fat chain
77 	 */
78 	uint32		iteration;
79 
80 	/* any changes to this block of information should immediately be reflected
81 	 * on the disk (or at least in the cache) so that get_next_dirent continues
82 	 * to function properly
83 	 */
84 	uint32		sindex, eindex;	// starting and ending index of directory entry
85 	uint32		cluster;		// starting cluster of the data
86 	uint32		mode;			// dos-style attributes
87 	off_t		st_size;		// in bytes
88 	time_t		st_time;
89 
90 	uint32		end_cluster;	// last cluster of the data
91 
92 	const char *mime;			// mime type (null if none)
93 
94 	bool		dirty;			// track if vnode had been written to
95 
96 #if TRACK_FILENAME
97 	char		*filename;
98 #endif
99 } vnode;
100 
101 // mode bits
102 #define FAT_READ_ONLY	1
103 #define FAT_HIDDEN		2
104 #define FAT_SYSTEM		4
105 #define FAT_VOLUME		8
106 #define FAT_SUBDIR		16
107 #define FAT_ARCHIVE		32
108 
109 
110 struct vcache_entry;
111 
112 typedef struct _nspace {
113 	fs_volume		*volume;		// fs_volume passed in to fs_mount
114 	dev_t			id;
115 	int				fd;				// File descriptor
116 	char			device[256];
117 	uint32			flags;			// see <fcntl.be.h> for modes
118 	void			*fBlockCache;
119 
120 	// info from bpb
121 	uint32	bytes_per_sector;
122 	uint32	sectors_per_cluster;
123 	uint32	reserved_sectors;
124 	uint32	fat_count;
125 	uint32	root_entries_count;
126 	uint32	total_sectors;
127 	uint32	sectors_per_fat;
128 	uint8	media_descriptor;
129 	uint16	fsinfo_sector;
130 
131 	uint32	total_clusters;			// data clusters, that is
132 	uint32	free_clusters;
133 	uint8	fat_bits;
134 	bool	fat_mirrored;			// true if fat mirroring on
135 	uint8	active_fat;
136 
137 	uint32  root_start;				// for fat12 + fat16 only
138 	uint32	root_sectors;			// for fat12 + fat16 only
139 	vnode	root_vnode;				// root directory
140 	int32	vol_entry;				// index in root directory
141 	char	vol_label[12];			// lfn's need not apply
142 
143 	uint32	data_start;
144 	uint32  last_allocated;			// last allocated cluster
145 
146 	ino_t	beos_vnid;				// vnid of \BEOS directory
147 	bool	respect_disk_image;
148 
149 	int		fs_flags;				// flags for this mount
150 
151 	recursive_lock	vlock;					// volume lock
152 
153 	// vcache state
154 	struct {
155 		rw_lock	lock;
156 		ino_t	cur_vnid;
157 		uint32	cache_size;
158 		struct vcache_entry **by_vnid, **by_loc;
159 	} vcache;
160 
161 	struct {
162 		uint32	entries;
163 		uint32	allocated;
164 		ino_t	*vnid_list;
165 	} dlist;
166 } nspace;
167 
168 #define FS_FLAGS_OP_SYNC       0x1
169 #define FS_FLAGS_LOCK_DOOR     0x2
170 
171 #define LOCK_VOL(vol) \
172 	if (vol == NULL) { dprintf("null vol\n"); return EINVAL; } else LOCK((vol)->vlock)
173 
174 #define UNLOCK_VOL(vol) \
175 	UNLOCK((vol)->vlock)
176 
177 #define TOUCH(x) ((void)(x))
178 
179 extern fs_vnode_ops gFATVnodeOps;
180 extern fs_volume_ops gFATVolumeOps;
181 
182 /* debug levels */
183 extern int debug_attr, debug_dir, debug_dlist, debug_dosfs, debug_encodings,
184 		debug_fat, debug_file, debug_iter, debug_vcache;
185 
186 status_t _dosfs_sync(nspace *vol);
187 
188 #endif
189