Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) | |
3 | * Licensed under the GPL | |
4 | */ | |
5 | ||
6 | #include <linux/fs.h> | |
7 | #include <linux/module.h> | |
8 | #include <linux/init.h> | |
9 | #include <linux/slab.h> | |
10 | #include <linux/list.h> | |
11 | #include <linux/kernel.h> | |
12 | #include <linux/ctype.h> | |
13 | #include <linux/dcache.h> | |
14 | #include <linux/statfs.h> | |
15 | #include <asm/uaccess.h> | |
16 | #include <asm/fcntl.h> | |
17 | #include "os.h" | |
18 | ||
19 | static int init_inode(struct inode *inode, struct dentry *dentry); | |
20 | ||
21 | struct hppfs_data { | |
22 | struct list_head list; | |
23 | char contents[PAGE_SIZE - sizeof(struct list_head)]; | |
24 | }; | |
25 | ||
26 | struct hppfs_private { | |
27 | struct file *proc_file; | |
28 | int host_fd; | |
29 | loff_t len; | |
30 | struct hppfs_data *contents; | |
31 | }; | |
32 | ||
33 | struct hppfs_inode_info { | |
34 | struct dentry *proc_dentry; | |
35 | struct inode vfs_inode; | |
36 | }; | |
37 | ||
38 | static inline struct hppfs_inode_info *HPPFS_I(struct inode *inode) | |
39 | { | |
40 | return(list_entry(inode, struct hppfs_inode_info, vfs_inode)); | |
41 | } | |
42 | ||
43 | #define HPPFS_SUPER_MAGIC 0xb00000ee | |
44 | ||
45 | static struct super_operations hppfs_sbops; | |
46 | ||
47 | static int is_pid(struct dentry *dentry) | |
48 | { | |
49 | struct super_block *sb; | |
50 | int i; | |
51 | ||
52 | sb = dentry->d_sb; | |
53 | if((sb->s_op != &hppfs_sbops) || (dentry->d_parent != sb->s_root)) | |
54 | return(0); | |
55 | ||
56 | for(i = 0; i < dentry->d_name.len; i++){ | |
57 | if(!isdigit(dentry->d_name.name[i])) | |
58 | return(0); | |
59 | } | |
60 | return(1); | |
61 | } | |
62 | ||
63 | static char *dentry_name(struct dentry *dentry, int extra) | |
64 | { | |
65 | struct dentry *parent; | |
66 | char *root, *name; | |
67 | const char *seg_name; | |
68 | int len, seg_len; | |
69 | ||
70 | len = 0; | |
71 | parent = dentry; | |
72 | while(parent->d_parent != parent){ | |
73 | if(is_pid(parent)) | |
74 | len += strlen("pid") + 1; | |
75 | else len += parent->d_name.len + 1; | |
76 | parent = parent->d_parent; | |
77 | } | |
78 | ||
79 | root = "proc"; | |
80 | len += strlen(root); | |
81 | name = kmalloc(len + extra + 1, GFP_KERNEL); | |
82 | if(name == NULL) return(NULL); | |
83 | ||
84 | name[len] = '\0'; | |
85 | parent = dentry; | |
86 | while(parent->d_parent != parent){ | |
87 | if(is_pid(parent)){ | |
88 | seg_name = "pid"; | |
89 | seg_len = strlen("pid"); | |
90 | } | |
91 | else { | |
92 | seg_name = parent->d_name.name; | |
93 | seg_len = parent->d_name.len; | |
94 | } | |
95 | ||
96 | len -= seg_len + 1; | |
97 | name[len] = '/'; | |
98 | strncpy(&name[len + 1], seg_name, seg_len); | |
99 | parent = parent->d_parent; | |
100 | } | |
101 | strncpy(name, root, strlen(root)); | |
102 | return(name); | |
103 | } | |
104 | ||
105 | struct dentry_operations hppfs_dentry_ops = { | |
106 | }; | |
107 | ||
108 | static int file_removed(struct dentry *dentry, const char *file) | |
109 | { | |
110 | char *host_file; | |
111 | int extra, fd; | |
112 | ||
113 | extra = 0; | |
114 | if(file != NULL) extra += strlen(file) + 1; | |
115 | ||
116 | host_file = dentry_name(dentry, extra + strlen("/remove")); | |
117 | if(host_file == NULL){ | |
118 | printk("file_removed : allocation failed\n"); | |
119 | return(-ENOMEM); | |
120 | } | |
121 | ||
122 | if(file != NULL){ | |
123 | strcat(host_file, "/"); | |
124 | strcat(host_file, file); | |
125 | } | |
126 | strcat(host_file, "/remove"); | |
127 | ||
128 | fd = os_open_file(host_file, of_read(OPENFLAGS()), 0); | |
129 | kfree(host_file); | |
130 | if(fd > 0){ | |
131 | os_close_file(fd); | |
132 | return(1); | |
133 | } | |
134 | return(0); | |
135 | } | |
136 | ||
137 | static void hppfs_read_inode(struct inode *ino) | |
138 | { | |
139 | struct inode *proc_ino; | |
140 | ||
141 | if(HPPFS_I(ino)->proc_dentry == NULL) | |
142 | return; | |
143 | ||
144 | proc_ino = HPPFS_I(ino)->proc_dentry->d_inode; | |
145 | ino->i_uid = proc_ino->i_uid; | |
146 | ino->i_gid = proc_ino->i_gid; | |
147 | ino->i_atime = proc_ino->i_atime; | |
148 | ino->i_mtime = proc_ino->i_mtime; | |
149 | ino->i_ctime = proc_ino->i_ctime; | |
150 | ino->i_ino = proc_ino->i_ino; | |
151 | ino->i_mode = proc_ino->i_mode; | |
152 | ino->i_nlink = proc_ino->i_nlink; | |
153 | ino->i_size = proc_ino->i_size; | |
154 | ino->i_blksize = proc_ino->i_blksize; | |
155 | ino->i_blocks = proc_ino->i_blocks; | |
156 | } | |
157 | ||
158 | static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry, | |
159 | struct nameidata *nd) | |
160 | { | |
161 | struct dentry *proc_dentry, *new, *parent; | |
162 | struct inode *inode; | |
163 | int err, deleted; | |
164 | ||
165 | deleted = file_removed(dentry, NULL); | |
166 | if(deleted < 0) | |
167 | return(ERR_PTR(deleted)); | |
168 | else if(deleted) | |
169 | return(ERR_PTR(-ENOENT)); | |
170 | ||
171 | err = -ENOMEM; | |
172 | parent = HPPFS_I(ino)->proc_dentry; | |
173 | down(&parent->d_inode->i_sem); | |
174 | proc_dentry = d_lookup(parent, &dentry->d_name); | |
175 | if(proc_dentry == NULL){ | |
176 | proc_dentry = d_alloc(parent, &dentry->d_name); | |
177 | if(proc_dentry == NULL){ | |
178 | up(&parent->d_inode->i_sem); | |
179 | goto out; | |
180 | } | |
181 | new = (*parent->d_inode->i_op->lookup)(parent->d_inode, | |
182 | proc_dentry, NULL); | |
183 | if(new){ | |
184 | dput(proc_dentry); | |
185 | proc_dentry = new; | |
186 | } | |
187 | } | |
188 | up(&parent->d_inode->i_sem); | |
189 | ||
190 | if(IS_ERR(proc_dentry)) | |
191 | return(proc_dentry); | |
192 | ||
193 | inode = iget(ino->i_sb, 0); | |
194 | if(inode == NULL) | |
195 | goto out_dput; | |
196 | ||
197 | err = init_inode(inode, proc_dentry); | |
198 | if(err) | |
199 | goto out_put; | |
200 | ||
201 | hppfs_read_inode(inode); | |
202 | ||
203 | d_add(dentry, inode); | |
204 | dentry->d_op = &hppfs_dentry_ops; | |
205 | return(NULL); | |
206 | ||
207 | out_put: | |
208 | iput(inode); | |
209 | out_dput: | |
210 | dput(proc_dentry); | |
211 | out: | |
212 | return(ERR_PTR(err)); | |
213 | } | |
214 | ||
215 | static struct inode_operations hppfs_file_iops = { | |
216 | }; | |
217 | ||
218 | static ssize_t read_proc(struct file *file, char *buf, ssize_t count, | |
219 | loff_t *ppos, int is_user) | |
220 | { | |
221 | ssize_t (*read)(struct file *, char *, size_t, loff_t *); | |
222 | ssize_t n; | |
223 | ||
224 | read = file->f_dentry->d_inode->i_fop->read; | |
225 | ||
226 | if(!is_user) | |
227 | set_fs(KERNEL_DS); | |
228 | ||
229 | n = (*read)(file, buf, count, &file->f_pos); | |
230 | ||
231 | if(!is_user) | |
232 | set_fs(USER_DS); | |
233 | ||
234 | if(ppos) *ppos = file->f_pos; | |
235 | return(n); | |
236 | } | |
237 | ||
238 | static ssize_t hppfs_read_file(int fd, char *buf, ssize_t count) | |
239 | { | |
240 | ssize_t n; | |
241 | int cur, err; | |
242 | char *new_buf; | |
243 | ||
244 | n = -ENOMEM; | |
245 | new_buf = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
246 | if(new_buf == NULL){ | |
247 | printk("hppfs_read_file : kmalloc failed\n"); | |
248 | goto out; | |
249 | } | |
250 | n = 0; | |
251 | while(count > 0){ | |
252 | cur = min_t(ssize_t, count, PAGE_SIZE); | |
253 | err = os_read_file(fd, new_buf, cur); | |
254 | if(err < 0){ | |
255 | printk("hppfs_read : read failed, errno = %d\n", | |
256 | count); | |
257 | n = err; | |
258 | goto out_free; | |
259 | } | |
260 | else if(err == 0) | |
261 | break; | |
262 | ||
263 | if(copy_to_user(buf, new_buf, err)){ | |
264 | n = -EFAULT; | |
265 | goto out_free; | |
266 | } | |
267 | n += err; | |
268 | count -= err; | |
269 | } | |
270 | out_free: | |
271 | kfree(new_buf); | |
272 | out: | |
273 | return(n); | |
274 | } | |
275 | ||
276 | static ssize_t hppfs_read(struct file *file, char *buf, size_t count, | |
277 | loff_t *ppos) | |
278 | { | |
279 | struct hppfs_private *hppfs = file->private_data; | |
280 | struct hppfs_data *data; | |
281 | loff_t off; | |
282 | int err; | |
283 | ||
284 | if(hppfs->contents != NULL){ | |
285 | if(*ppos >= hppfs->len) return(0); | |
286 | ||
287 | data = hppfs->contents; | |
288 | off = *ppos; | |
289 | while(off >= sizeof(data->contents)){ | |
290 | data = list_entry(data->list.next, struct hppfs_data, | |
291 | list); | |
292 | off -= sizeof(data->contents); | |
293 | } | |
294 | ||
295 | if(off + count > hppfs->len) | |
296 | count = hppfs->len - off; | |
297 | copy_to_user(buf, &data->contents[off], count); | |
298 | *ppos += count; | |
299 | } | |
300 | else if(hppfs->host_fd != -1){ | |
301 | err = os_seek_file(hppfs->host_fd, *ppos); | |
302 | if(err){ | |
303 | printk("hppfs_read : seek failed, errno = %d\n", err); | |
304 | return(err); | |
305 | } | |
306 | count = hppfs_read_file(hppfs->host_fd, buf, count); | |
307 | if(count > 0) | |
308 | *ppos += count; | |
309 | } | |
310 | else count = read_proc(hppfs->proc_file, buf, count, ppos, 1); | |
311 | ||
312 | return(count); | |
313 | } | |
314 | ||
315 | static ssize_t hppfs_write(struct file *file, const char *buf, size_t len, | |
316 | loff_t *ppos) | |
317 | { | |
318 | struct hppfs_private *data = file->private_data; | |
319 | struct file *proc_file = data->proc_file; | |
320 | ssize_t (*write)(struct file *, const char *, size_t, loff_t *); | |
321 | int err; | |
322 | ||
323 | write = proc_file->f_dentry->d_inode->i_fop->write; | |
324 | ||
325 | proc_file->f_pos = file->f_pos; | |
326 | err = (*write)(proc_file, buf, len, &proc_file->f_pos); | |
327 | file->f_pos = proc_file->f_pos; | |
328 | ||
329 | return(err); | |
330 | } | |
331 | ||
332 | static int open_host_sock(char *host_file, int *filter_out) | |
333 | { | |
334 | char *end; | |
335 | int fd; | |
336 | ||
337 | end = &host_file[strlen(host_file)]; | |
338 | strcpy(end, "/rw"); | |
339 | *filter_out = 1; | |
340 | fd = os_connect_socket(host_file); | |
341 | if(fd > 0) | |
342 | return(fd); | |
343 | ||
344 | strcpy(end, "/r"); | |
345 | *filter_out = 0; | |
346 | fd = os_connect_socket(host_file); | |
347 | return(fd); | |
348 | } | |
349 | ||
350 | static void free_contents(struct hppfs_data *head) | |
351 | { | |
352 | struct hppfs_data *data; | |
353 | struct list_head *ele, *next; | |
354 | ||
355 | if(head == NULL) return; | |
356 | ||
357 | list_for_each_safe(ele, next, &head->list){ | |
358 | data = list_entry(ele, struct hppfs_data, list); | |
359 | kfree(data); | |
360 | } | |
361 | kfree(head); | |
362 | } | |
363 | ||
364 | static struct hppfs_data *hppfs_get_data(int fd, int filter, | |
365 | struct file *proc_file, | |
366 | struct file *hppfs_file, | |
367 | loff_t *size_out) | |
368 | { | |
369 | struct hppfs_data *data, *new, *head; | |
370 | int n, err; | |
371 | ||
372 | err = -ENOMEM; | |
373 | data = kmalloc(sizeof(*data), GFP_KERNEL); | |
374 | if(data == NULL){ | |
375 | printk("hppfs_get_data : head allocation failed\n"); | |
376 | goto failed; | |
377 | } | |
378 | ||
379 | INIT_LIST_HEAD(&data->list); | |
380 | ||
381 | head = data; | |
382 | *size_out = 0; | |
383 | ||
384 | if(filter){ | |
385 | while((n = read_proc(proc_file, data->contents, | |
386 | sizeof(data->contents), NULL, 0)) > 0) | |
387 | os_write_file(fd, data->contents, n); | |
388 | err = os_shutdown_socket(fd, 0, 1); | |
389 | if(err){ | |
390 | printk("hppfs_get_data : failed to shut down " | |
391 | "socket\n"); | |
392 | goto failed_free; | |
393 | } | |
394 | } | |
395 | while(1){ | |
396 | n = os_read_file(fd, data->contents, sizeof(data->contents)); | |
397 | if(n < 0){ | |
398 | err = n; | |
399 | printk("hppfs_get_data : read failed, errno = %d\n", | |
400 | err); | |
401 | goto failed_free; | |
402 | } | |
403 | else if(n == 0) | |
404 | break; | |
405 | ||
406 | *size_out += n; | |
407 | ||
408 | if(n < sizeof(data->contents)) | |
409 | break; | |
410 | ||
411 | new = kmalloc(sizeof(*data), GFP_KERNEL); | |
412 | if(new == 0){ | |
413 | printk("hppfs_get_data : data allocation failed\n"); | |
414 | err = -ENOMEM; | |
415 | goto failed_free; | |
416 | } | |
417 | ||
418 | INIT_LIST_HEAD(&new->list); | |
419 | list_add(&new->list, &data->list); | |
420 | data = new; | |
421 | } | |
422 | return(head); | |
423 | ||
424 | failed_free: | |
425 | free_contents(head); | |
426 | failed: | |
427 | return(ERR_PTR(err)); | |
428 | } | |
429 | ||
430 | static struct hppfs_private *hppfs_data(void) | |
431 | { | |
432 | struct hppfs_private *data; | |
433 | ||
434 | data = kmalloc(sizeof(*data), GFP_KERNEL); | |
435 | if(data == NULL) | |
436 | return(data); | |
437 | ||
438 | *data = ((struct hppfs_private ) { .host_fd = -1, | |
439 | .len = -1, | |
440 | .contents = NULL } ); | |
441 | return(data); | |
442 | } | |
443 | ||
444 | static int file_mode(int fmode) | |
445 | { | |
446 | if(fmode == (FMODE_READ | FMODE_WRITE)) | |
447 | return(O_RDWR); | |
448 | if(fmode == FMODE_READ) | |
449 | return(O_RDONLY); | |
450 | if(fmode == FMODE_WRITE) | |
451 | return(O_WRONLY); | |
452 | return(0); | |
453 | } | |
454 | ||
455 | static int hppfs_open(struct inode *inode, struct file *file) | |
456 | { | |
457 | struct hppfs_private *data; | |
458 | struct dentry *proc_dentry; | |
459 | char *host_file; | |
460 | int err, fd, type, filter; | |
461 | ||
462 | err = -ENOMEM; | |
463 | data = hppfs_data(); | |
464 | if(data == NULL) | |
465 | goto out; | |
466 | ||
467 | host_file = dentry_name(file->f_dentry, strlen("/rw")); | |
468 | if(host_file == NULL) | |
469 | goto out_free2; | |
470 | ||
471 | proc_dentry = HPPFS_I(inode)->proc_dentry; | |
472 | ||
473 | /* XXX This isn't closed anywhere */ | |
474 | data->proc_file = dentry_open(dget(proc_dentry), NULL, | |
475 | file_mode(file->f_mode)); | |
476 | err = PTR_ERR(data->proc_file); | |
477 | if(IS_ERR(data->proc_file)) | |
478 | goto out_free1; | |
479 | ||
480 | type = os_file_type(host_file); | |
481 | if(type == OS_TYPE_FILE){ | |
482 | fd = os_open_file(host_file, of_read(OPENFLAGS()), 0); | |
483 | if(fd >= 0) | |
484 | data->host_fd = fd; | |
485 | else printk("hppfs_open : failed to open '%s', errno = %d\n", | |
486 | host_file, -fd); | |
487 | ||
488 | data->contents = NULL; | |
489 | } | |
490 | else if(type == OS_TYPE_DIR){ | |
491 | fd = open_host_sock(host_file, &filter); | |
492 | if(fd > 0){ | |
493 | data->contents = hppfs_get_data(fd, filter, | |
494 | &data->proc_file, | |
495 | file, &data->len); | |
496 | if(!IS_ERR(data->contents)) | |
497 | data->host_fd = fd; | |
498 | } | |
499 | else printk("hppfs_open : failed to open a socket in " | |
500 | "'%s', errno = %d\n", host_file, -fd); | |
501 | } | |
502 | kfree(host_file); | |
503 | ||
504 | file->private_data = data; | |
505 | return(0); | |
506 | ||
507 | out_free1: | |
508 | kfree(host_file); | |
509 | out_free2: | |
510 | free_contents(data->contents); | |
511 | kfree(data); | |
512 | out: | |
513 | return(err); | |
514 | } | |
515 | ||
516 | static int hppfs_dir_open(struct inode *inode, struct file *file) | |
517 | { | |
518 | struct hppfs_private *data; | |
519 | struct dentry *proc_dentry; | |
520 | int err; | |
521 | ||
522 | err = -ENOMEM; | |
523 | data = hppfs_data(); | |
524 | if(data == NULL) | |
525 | goto out; | |
526 | ||
527 | proc_dentry = HPPFS_I(inode)->proc_dentry; | |
528 | data->proc_file = dentry_open(dget(proc_dentry), NULL, | |
529 | file_mode(file->f_mode)); | |
530 | err = PTR_ERR(data->proc_file); | |
531 | if(IS_ERR(data->proc_file)) | |
532 | goto out_free; | |
533 | ||
534 | file->private_data = data; | |
535 | return(0); | |
536 | ||
537 | out_free: | |
538 | kfree(data); | |
539 | out: | |
540 | return(err); | |
541 | } | |
542 | ||
543 | static loff_t hppfs_llseek(struct file *file, loff_t off, int where) | |
544 | { | |
545 | struct hppfs_private *data = file->private_data; | |
546 | struct file *proc_file = &data->proc_file; | |
547 | loff_t (*llseek)(struct file *, loff_t, int); | |
548 | loff_t ret; | |
549 | ||
550 | llseek = proc_file->f_dentry->d_inode->i_fop->llseek; | |
551 | if(llseek != NULL){ | |
552 | ret = (*llseek)(proc_file, off, where); | |
553 | if(ret < 0) | |
554 | return(ret); | |
555 | } | |
556 | ||
557 | return(default_llseek(file, off, where)); | |
558 | } | |
559 | ||
560 | static struct file_operations hppfs_file_fops = { | |
561 | .owner = NULL, | |
562 | .llseek = hppfs_llseek, | |
563 | .read = hppfs_read, | |
564 | .write = hppfs_write, | |
565 | .open = hppfs_open, | |
566 | }; | |
567 | ||
568 | struct hppfs_dirent { | |
569 | void *vfs_dirent; | |
570 | filldir_t filldir; | |
571 | struct dentry *dentry; | |
572 | }; | |
573 | ||
574 | static int hppfs_filldir(void *d, const char *name, int size, | |
575 | loff_t offset, ino_t inode, unsigned int type) | |
576 | { | |
577 | struct hppfs_dirent *dirent = d; | |
578 | ||
579 | if(file_removed(dirent->dentry, name)) | |
580 | return(0); | |
581 | ||
582 | return((*dirent->filldir)(dirent->vfs_dirent, name, size, offset, | |
583 | inode, type)); | |
584 | } | |
585 | ||
586 | static int hppfs_readdir(struct file *file, void *ent, filldir_t filldir) | |
587 | { | |
588 | struct hppfs_private *data = file->private_data; | |
589 | struct file *proc_file = &data->proc_file; | |
590 | int (*readdir)(struct file *, void *, filldir_t); | |
591 | struct hppfs_dirent dirent = ((struct hppfs_dirent) | |
592 | { .vfs_dirent = ent, | |
593 | .filldir = filldir, | |
594 | .dentry = file->f_dentry } ); | |
595 | int err; | |
596 | ||
597 | readdir = proc_file->f_dentry->d_inode->i_fop->readdir; | |
598 | ||
599 | proc_file->f_pos = file->f_pos; | |
600 | err = (*readdir)(proc_file, &dirent, hppfs_filldir); | |
601 | file->f_pos = proc_file->f_pos; | |
602 | ||
603 | return(err); | |
604 | } | |
605 | ||
606 | static int hppfs_fsync(struct file *file, struct dentry *dentry, int datasync) | |
607 | { | |
608 | return(0); | |
609 | } | |
610 | ||
611 | static struct file_operations hppfs_dir_fops = { | |
612 | .owner = NULL, | |
613 | .readdir = hppfs_readdir, | |
614 | .open = hppfs_dir_open, | |
615 | .fsync = hppfs_fsync, | |
616 | }; | |
617 | ||
618 | static int hppfs_statfs(struct super_block *sb, struct kstatfs *sf) | |
619 | { | |
620 | sf->f_blocks = 0; | |
621 | sf->f_bfree = 0; | |
622 | sf->f_bavail = 0; | |
623 | sf->f_files = 0; | |
624 | sf->f_ffree = 0; | |
625 | sf->f_type = HPPFS_SUPER_MAGIC; | |
626 | return(0); | |
627 | } | |
628 | ||
629 | static struct inode *hppfs_alloc_inode(struct super_block *sb) | |
630 | { | |
631 | struct hppfs_inode_info *hi; | |
632 | ||
633 | hi = kmalloc(sizeof(*hi), GFP_KERNEL); | |
634 | if(hi == NULL) | |
635 | return(NULL); | |
636 | ||
637 | *hi = ((struct hppfs_inode_info) { .proc_dentry = NULL }); | |
638 | inode_init_once(&hi->vfs_inode); | |
639 | return(&hi->vfs_inode); | |
640 | } | |
641 | ||
642 | void hppfs_delete_inode(struct inode *ino) | |
643 | { | |
644 | clear_inode(ino); | |
645 | } | |
646 | ||
647 | static void hppfs_destroy_inode(struct inode *inode) | |
648 | { | |
649 | kfree(HPPFS_I(inode)); | |
650 | } | |
651 | ||
652 | static struct super_operations hppfs_sbops = { | |
653 | .alloc_inode = hppfs_alloc_inode, | |
654 | .destroy_inode = hppfs_destroy_inode, | |
655 | .read_inode = hppfs_read_inode, | |
656 | .delete_inode = hppfs_delete_inode, | |
657 | .statfs = hppfs_statfs, | |
658 | }; | |
659 | ||
660 | static int hppfs_readlink(struct dentry *dentry, char *buffer, int buflen) | |
661 | { | |
662 | struct file *proc_file; | |
663 | struct dentry *proc_dentry; | |
664 | int (*readlink)(struct dentry *, char *, int); | |
665 | int err, n; | |
666 | ||
667 | proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry; | |
668 | proc_file = dentry_open(dget(proc_dentry), NULL, O_RDONLY); | |
669 | err = PTR_ERR(proc_dentry); | |
670 | if(IS_ERR(proc_dentry)) | |
671 | return(err); | |
672 | ||
673 | readlink = proc_dentry->d_inode->i_op->readlink; | |
674 | n = (*readlink)(proc_dentry, buffer, buflen); | |
675 | ||
676 | fput(proc_file); | |
677 | ||
678 | return(n); | |
679 | } | |
680 | ||
681 | static int hppfs_follow_link(struct dentry *dentry, struct nameidata *nd) | |
682 | { | |
683 | struct file *proc_file; | |
684 | struct dentry *proc_dentry; | |
685 | int (*follow_link)(struct dentry *, struct nameidata *); | |
686 | int err, n; | |
687 | ||
688 | proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry; | |
689 | proc_file = dentry_open(dget(proc_dentry), NULL, O_RDONLY); | |
690 | err = PTR_ERR(proc_dentry); | |
691 | if(IS_ERR(proc_dentry)) | |
692 | return(err); | |
693 | ||
694 | follow_link = proc_dentry->d_inode->i_op->follow_link; | |
695 | n = (*follow_link)(proc_dentry, nd); | |
696 | ||
697 | fput(proc_file); | |
698 | ||
699 | return(n); | |
700 | } | |
701 | ||
702 | static struct inode_operations hppfs_dir_iops = { | |
703 | .lookup = hppfs_lookup, | |
704 | }; | |
705 | ||
706 | static struct inode_operations hppfs_link_iops = { | |
707 | .readlink = hppfs_readlink, | |
708 | .follow_link = hppfs_follow_link, | |
709 | }; | |
710 | ||
711 | static int init_inode(struct inode *inode, struct dentry *dentry) | |
712 | { | |
713 | if(S_ISDIR(dentry->d_inode->i_mode)){ | |
714 | inode->i_op = &hppfs_dir_iops; | |
715 | inode->i_fop = &hppfs_dir_fops; | |
716 | } | |
717 | else if(S_ISLNK(dentry->d_inode->i_mode)){ | |
718 | inode->i_op = &hppfs_link_iops; | |
719 | inode->i_fop = &hppfs_file_fops; | |
720 | } | |
721 | else { | |
722 | inode->i_op = &hppfs_file_iops; | |
723 | inode->i_fop = &hppfs_file_fops; | |
724 | } | |
725 | ||
726 | HPPFS_I(inode)->proc_dentry = dentry; | |
727 | ||
728 | return(0); | |
729 | } | |
730 | ||
731 | static int hppfs_fill_super(struct super_block *sb, void *d, int silent) | |
732 | { | |
733 | struct inode *root_inode; | |
734 | struct file_system_type *procfs; | |
735 | struct super_block *proc_sb; | |
736 | int err; | |
737 | ||
738 | err = -ENOENT; | |
739 | procfs = get_fs_type("proc"); | |
740 | if(procfs == NULL) | |
741 | goto out; | |
742 | ||
743 | if(list_empty(&procfs->fs_supers)) | |
744 | goto out; | |
745 | ||
746 | proc_sb = list_entry(procfs->fs_supers.next, struct super_block, | |
747 | s_instances); | |
748 | ||
749 | sb->s_blocksize = 1024; | |
750 | sb->s_blocksize_bits = 10; | |
751 | sb->s_magic = HPPFS_SUPER_MAGIC; | |
752 | sb->s_op = &hppfs_sbops; | |
753 | ||
754 | root_inode = iget(sb, 0); | |
755 | if(root_inode == NULL) | |
756 | goto out; | |
757 | ||
758 | err = init_inode(root_inode, proc_sb->s_root); | |
759 | if(err) | |
760 | goto out_put; | |
761 | ||
762 | err = -ENOMEM; | |
763 | sb->s_root = d_alloc_root(root_inode); | |
764 | if(sb->s_root == NULL) | |
765 | goto out_put; | |
766 | ||
767 | hppfs_read_inode(root_inode); | |
768 | ||
769 | return(0); | |
770 | ||
771 | out_put: | |
772 | iput(root_inode); | |
773 | out: | |
774 | return(err); | |
775 | } | |
776 | ||
777 | static struct super_block *hppfs_read_super(struct file_system_type *type, | |
778 | int flags, const char *dev_name, | |
779 | void *data) | |
780 | { | |
781 | return(get_sb_nodev(type, flags, data, hppfs_fill_super)); | |
782 | } | |
783 | ||
784 | static struct file_system_type hppfs_type = { | |
785 | .owner = THIS_MODULE, | |
786 | .name = "hppfs", | |
787 | .get_sb = hppfs_read_super, | |
788 | .kill_sb = kill_anon_super, | |
789 | .fs_flags = 0, | |
790 | }; | |
791 | ||
792 | static int __init init_hppfs(void) | |
793 | { | |
794 | return(register_filesystem(&hppfs_type)); | |
795 | } | |
796 | ||
797 | static void __exit exit_hppfs(void) | |
798 | { | |
799 | unregister_filesystem(&hppfs_type); | |
800 | } | |
801 | ||
802 | module_init(init_hppfs) | |
803 | module_exit(exit_hppfs) | |
804 | MODULE_LICENSE("GPL"); | |
805 | ||
806 | /* | |
807 | * Overrides for Emacs so that we follow Linus's tabbing style. | |
808 | * Emacs will notice this stuff at the end of the file and automatically | |
809 | * adjust the settings for this buffer only. This must remain at the end | |
810 | * of the file. | |
811 | * --------------------------------------------------------------------------- | |
812 | * Local variables: | |
813 | * c-file-style: "linux" | |
814 | * End: | |
815 | */ |