1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
|
#ifndef FS_H
#define FS_H
#include <stddef.h>
#include <stdbool.h>
#include <string.h>
#include <com32.h>
#include <stdio.h>
#include <sys/dirent.h>
#include "core.h"
#include "disk.h"
/*
* Maximum number of open files. This is *currently* constrained by the
* fact that PXE needs to be able to fit all its packet buffers into a
* 64K segment; this should be fixed by moving the packet buffers to high
* memory.
*/
#define MAX_OPEN_LG2 5
#define MAX_OPEN (1 << MAX_OPEN_LG2)
#define FILENAME_MAX_LG2 8
#define FILENAME_MAX (1 << FILENAME_MAX_LG2)
#define CURRENTDIR_MAX FILENAME_MAX
#define BLOCK_SIZE(fs) ((fs)->block_size)
#define BLOCK_SHIFT(fs) ((fs)->block_shift)
#define SECTOR_SIZE(fs) ((fs)->sector_size)
#define SECTOR_SHIFT(fs) ((fs)->sector_shift)
struct fs_info {
const struct fs_ops *fs_ops;
struct device *fs_dev;
void *fs_info; /* The fs-specific information */
int sector_shift, sector_size;
int block_shift, block_size;
struct inode *root, *cwd; /* Root and current directories */
char cwd_name[CURRENTDIR_MAX]; /* Current directory by name */
};
extern struct fs_info *this_fs;
struct dirent; /* Directory entry structure */
struct file;
enum fs_flags {
FS_NODEV = 1 << 0,
FS_USEMEM = 1 << 1, /* If we need a malloc routine, set it */
FS_THISIND = 1 << 2, /* Set cwd based on config file location */
};
struct fs_ops {
/* in fact, we use fs_ops structure to find the right fs */
const char *fs_name;
enum fs_flags fs_flags;
int (*fs_init)(struct fs_info *);
void (*searchdir)(const char *, struct file *);
uint32_t (*getfssec)(struct file *, char *, int, bool *);
void (*close_file)(struct file *);
void (*mangle_name)(char *, const char *);
size_t (*realpath)(struct fs_info *, char *, const char *, size_t);
int (*chdir)(struct fs_info *, const char *);
int (*load_config)(void);
struct inode * (*iget_root)(struct fs_info *);
struct inode * (*iget)(const char *, struct inode *);
int (*readlink)(struct inode *, char *);
/* the _dir_ stuff */
struct dirent * (*readdir)(struct file *);
int (*next_extent)(struct inode *, uint32_t);
};
enum inode_mode {I_FILE, I_DIR, I_SYMLINK};
/*
* Extent structure: contains the mapping of some chunk of a file
* that is contiguous on disk.
*/
struct extent {
sector_t pstart; /* Physical start sector */
uint32_t lstart; /* Logical start sector */
uint32_t len; /* Number of contiguous sectors */
};
/* Special sector numbers used for struct extent.pstart */
#define EXTENT_ZERO ((sector_t)-1) /* All-zero extent */
#define EXTENT_VOID ((sector_t)-2) /* Invalid information */
#define EXTENT_SPECIAL(x) ((x) >= EXTENT_VOID)
/*
* The inode structure, including the detail file information
*/
struct inode {
struct fs_info *fs; /* The filesystem this inode is associated with */
int refcnt;
int mode; /* FILE , DIR or SYMLINK */
uint32_t size;
uint32_t blocks; /* How many blocks the file take */
uint32_t ino; /* Inode number */
uint32_t atime; /* Access time */
uint32_t mtime; /* Modify time */
uint32_t ctime; /* Create time */
uint32_t dtime; /* Delete time */
uint32_t flags;
uint32_t file_acl;
struct extent this_extent, next_extent;
char pvt[0]; /* Private filesystem data */
};
struct open_file_t;
struct file {
struct fs_info *fs;
uint32_t file_len;
union {
/* For the new universal-path_lookup */
struct {
struct inode *inode; /* The file-specific information */
uint32_t offset; /* for next read */
};
/* For the old searchdir method */
struct {
struct open_file_t *open_file;/* The fs-specific open file struct */
};
};
};
enum dev_type {CHS, EDD};
/*
* Struct device contains:
* the pointer points to the disk structure,
* the cache stuff.
*/
struct cache;
struct device {
struct disk *disk;
/* the cache stuff */
char *cache_data;
struct cache *cache_head;
uint16_t cache_block_size;
uint16_t cache_entries;
uint32_t cache_size;
};
/*
* Our definition of "not whitespace"
*/
static inline bool not_whitespace(char c)
{
return (unsigned char)c > ' ';
}
/*
* Inode allocator/deallocator
*/
struct inode *alloc_inode(struct fs_info *fs, uint32_t ino, size_t data);
static inline void free_inode(struct inode * inode)
{
free(inode);
}
static inline struct inode *get_inode(struct inode *inode)
{
inode->refcnt++;
return inode;
}
static inline void put_inode(struct inode *inode)
{
if (! --inode->refcnt)
free(inode);
}
static inline void malloc_error(char *obj)
{
printf("Out of memory: can't allocate memory for %s\n", obj);
kaboom();
}
/*
* File handle conversion functions
*/
extern struct file files[];
static inline uint16_t file_to_handle(struct file *file)
{
return file ? (file - files)+1 : 0;
}
static inline struct file *handle_to_file(uint16_t handle)
{
return handle ? &files[handle-1] : NULL;
}
/* fs.c */
void pm_mangle_name(com32sys_t *);
void pm_searchdir(com32sys_t *);
void mangle_name(char *, const char *);
int searchdir(const char *name);
void _close_file(struct file *);
size_t pmapi_read_file(uint16_t *handle, void *buf, size_t sectors);
/* chdir.c */
void pm_realpath(com32sys_t *regs);
size_t realpath(char *dst, const char *src, size_t bufsize);
int chdir(const char *src);
/* readdir.c */
DIR *opendir(const char *pathname);
struct dirent *readdir(DIR *dir);
int closedir(DIR *dir);
/*
* Generic functions that filesystem drivers may choose to use
*/
/* mangle.c */
void generic_mangle_name(char *, const char *);
/* loadconfig.c */
int generic_load_config(void);
/* close.c */
void generic_close_file(struct file *file);
/* getfssec.c */
uint32_t generic_getfssec(struct file *file, char *buf,
int sectors, bool *have_more);
/* nonextextent.c */
int no_next_extent(struct inode *, uint32_t);
#endif /* FS_H */
|