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30#include <linux/module.h>
31#include <linux/fs.h>
32#include <linux/mount.h>
33#include <linux/pagemap.h>
34#include <linux/init.h>
35#include <linux/proc_fs.h>
36#include <linux/usb.h>
37#include <linux/namei.h>
38#include <linux/usbdevice_fs.h>
39#include <linux/parser.h>
40#include <linux/notifier.h>
41#include <linux/seq_file.h>
42#include <linux/smp_lock.h>
43#include <asm/byteorder.h>
44#include "usb.h"
45#include "hcd.h"
46
47#define USBFS_DEFAULT_DEVMODE (S_IWUSR | S_IRUGO)
48#define USBFS_DEFAULT_BUSMODE (S_IXUGO | S_IRUGO)
49#define USBFS_DEFAULT_LISTMODE S_IRUGO
50
51static const struct file_operations default_file_operations;
52static struct vfsmount *usbfs_mount;
53static int usbfs_mount_count;
54static int ignore_mount = 0;
55
56static struct dentry *devices_usbfs_dentry;
57static int num_buses;
58
59static uid_t devuid;
60static uid_t busuid;
61static uid_t listuid;
62static gid_t devgid;
63static gid_t busgid;
64static gid_t listgid;
65static umode_t devmode = USBFS_DEFAULT_DEVMODE;
66static umode_t busmode = USBFS_DEFAULT_BUSMODE;
67static umode_t listmode = USBFS_DEFAULT_LISTMODE;
68
69static int usbfs_show_options(struct seq_file *seq, struct vfsmount *mnt)
70{
71 if (devuid != 0)
72 seq_printf(seq, ",devuid=%u", devuid);
73 if (devgid != 0)
74 seq_printf(seq, ",devgid=%u", devgid);
75 if (devmode != USBFS_DEFAULT_DEVMODE)
76 seq_printf(seq, ",devmode=%o", devmode);
77 if (busuid != 0)
78 seq_printf(seq, ",busuid=%u", busuid);
79 if (busgid != 0)
80 seq_printf(seq, ",busgid=%u", busgid);
81 if (busmode != USBFS_DEFAULT_BUSMODE)
82 seq_printf(seq, ",busmode=%o", busmode);
83 if (listuid != 0)
84 seq_printf(seq, ",listuid=%u", listuid);
85 if (listgid != 0)
86 seq_printf(seq, ",listgid=%u", listgid);
87 if (listmode != USBFS_DEFAULT_LISTMODE)
88 seq_printf(seq, ",listmode=%o", listmode);
89
90 return 0;
91}
92
93enum {
94 Opt_devuid, Opt_devgid, Opt_devmode,
95 Opt_busuid, Opt_busgid, Opt_busmode,
96 Opt_listuid, Opt_listgid, Opt_listmode,
97 Opt_err,
98};
99
100static const match_table_t tokens = {
101 {Opt_devuid, "devuid=%u"},
102 {Opt_devgid, "devgid=%u"},
103 {Opt_devmode, "devmode=%o"},
104 {Opt_busuid, "busuid=%u"},
105 {Opt_busgid, "busgid=%u"},
106 {Opt_busmode, "busmode=%o"},
107 {Opt_listuid, "listuid=%u"},
108 {Opt_listgid, "listgid=%u"},
109 {Opt_listmode, "listmode=%o"},
110 {Opt_err, NULL}
111};
112
113static int parse_options(struct super_block *s, char *data)
114{
115 char *p;
116 int option;
117
118
119 devuid = 0;
120 busuid = 0;
121 listuid = 0;
122 devgid = 0;
123 busgid = 0;
124 listgid = 0;
125 devmode = USBFS_DEFAULT_DEVMODE;
126 busmode = USBFS_DEFAULT_BUSMODE;
127 listmode = USBFS_DEFAULT_LISTMODE;
128
129 while ((p = strsep(&data, ",")) != NULL) {
130 substring_t args[MAX_OPT_ARGS];
131 int token;
132 if (!*p)
133 continue;
134
135 token = match_token(p, tokens, args);
136 switch (token) {
137 case Opt_devuid:
138 if (match_int(&args[0], &option))
139 return -EINVAL;
140 devuid = option;
141 break;
142 case Opt_devgid:
143 if (match_int(&args[0], &option))
144 return -EINVAL;
145 devgid = option;
146 break;
147 case Opt_devmode:
148 if (match_octal(&args[0], &option))
149 return -EINVAL;
150 devmode = option & S_IRWXUGO;
151 break;
152 case Opt_busuid:
153 if (match_int(&args[0], &option))
154 return -EINVAL;
155 busuid = option;
156 break;
157 case Opt_busgid:
158 if (match_int(&args[0], &option))
159 return -EINVAL;
160 busgid = option;
161 break;
162 case Opt_busmode:
163 if (match_octal(&args[0], &option))
164 return -EINVAL;
165 busmode = option & S_IRWXUGO;
166 break;
167 case Opt_listuid:
168 if (match_int(&args[0], &option))
169 return -EINVAL;
170 listuid = option;
171 break;
172 case Opt_listgid:
173 if (match_int(&args[0], &option))
174 return -EINVAL;
175 listgid = option;
176 break;
177 case Opt_listmode:
178 if (match_octal(&args[0], &option))
179 return -EINVAL;
180 listmode = option & S_IRWXUGO;
181 break;
182 default:
183 printk(KERN_ERR "usbfs: unrecognised mount option "
184 "\"%s\" or missing value\n", p);
185 return -EINVAL;
186 }
187 }
188
189 return 0;
190}
191
192static void update_special(struct dentry *special)
193{
194 special->d_inode->i_uid = listuid;
195 special->d_inode->i_gid = listgid;
196 special->d_inode->i_mode = S_IFREG | listmode;
197}
198
199static void update_dev(struct dentry *dev)
200{
201 dev->d_inode->i_uid = devuid;
202 dev->d_inode->i_gid = devgid;
203 dev->d_inode->i_mode = S_IFREG | devmode;
204}
205
206static void update_bus(struct dentry *bus)
207{
208 struct dentry *dev = NULL;
209
210 bus->d_inode->i_uid = busuid;
211 bus->d_inode->i_gid = busgid;
212 bus->d_inode->i_mode = S_IFDIR | busmode;
213
214 mutex_lock(&bus->d_inode->i_mutex);
215
216 list_for_each_entry(dev, &bus->d_subdirs, d_u.d_child)
217 if (dev->d_inode)
218 update_dev(dev);
219
220 mutex_unlock(&bus->d_inode->i_mutex);
221}
222
223static void update_sb(struct super_block *sb)
224{
225 struct dentry *root = sb->s_root;
226 struct dentry *bus = NULL;
227
228 if (!root)
229 return;
230
231 mutex_lock_nested(&root->d_inode->i_mutex, I_MUTEX_PARENT);
232
233 list_for_each_entry(bus, &root->d_subdirs, d_u.d_child) {
234 if (bus->d_inode) {
235 switch (S_IFMT & bus->d_inode->i_mode) {
236 case S_IFDIR:
237 update_bus(bus);
238 break;
239 case S_IFREG:
240 update_special(bus);
241 break;
242 default:
243 printk(KERN_WARNING "usbfs: Unknown node %s "
244 "mode %x found on remount!\n",
245 bus->d_name.name, bus->d_inode->i_mode);
246 break;
247 }
248 }
249 }
250
251 mutex_unlock(&root->d_inode->i_mutex);
252}
253
254static int remount(struct super_block *sb, int *flags, char *data)
255{
256
257
258
259
260 if (ignore_mount)
261 return 0;
262
263 if (parse_options(sb, data)) {
264 printk(KERN_WARNING "usbfs: mount parameter error.\n");
265 return -EINVAL;
266 }
267
268 lock_kernel();
269
270 if (usbfs_mount && usbfs_mount->mnt_sb)
271 update_sb(usbfs_mount->mnt_sb);
272
273 unlock_kernel();
274
275 return 0;
276}
277
278static struct inode *usbfs_get_inode (struct super_block *sb, int mode, dev_t dev)
279{
280 struct inode *inode = new_inode(sb);
281
282 if (inode) {
283 inode->i_mode = mode;
284 inode->i_uid = current_fsuid();
285 inode->i_gid = current_fsgid();
286 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
287 switch (mode & S_IFMT) {
288 default:
289 init_special_inode(inode, mode, dev);
290 break;
291 case S_IFREG:
292 inode->i_fop = &default_file_operations;
293 break;
294 case S_IFDIR:
295 inode->i_op = &simple_dir_inode_operations;
296 inode->i_fop = &simple_dir_operations;
297
298
299 inc_nlink(inode);
300 break;
301 }
302 }
303 return inode;
304}
305
306
307static int usbfs_mknod (struct inode *dir, struct dentry *dentry, int mode,
308 dev_t dev)
309{
310 struct inode *inode = usbfs_get_inode(dir->i_sb, mode, dev);
311 int error = -EPERM;
312
313 if (dentry->d_inode)
314 return -EEXIST;
315
316 if (inode) {
317 d_instantiate(dentry, inode);
318 dget(dentry);
319 error = 0;
320 }
321 return error;
322}
323
324static int usbfs_mkdir (struct inode *dir, struct dentry *dentry, int mode)
325{
326 int res;
327
328 mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR;
329 res = usbfs_mknod (dir, dentry, mode, 0);
330 if (!res)
331 inc_nlink(dir);
332 return res;
333}
334
335static int usbfs_create (struct inode *dir, struct dentry *dentry, int mode)
336{
337 mode = (mode & S_IALLUGO) | S_IFREG;
338 return usbfs_mknod (dir, dentry, mode, 0);
339}
340
341static inline int usbfs_positive (struct dentry *dentry)
342{
343 return dentry->d_inode && !d_unhashed(dentry);
344}
345
346static int usbfs_empty (struct dentry *dentry)
347{
348 struct list_head *list;
349
350 spin_lock(&dcache_lock);
351
352 list_for_each(list, &dentry->d_subdirs) {
353 struct dentry *de = list_entry(list, struct dentry, d_u.d_child);
354 if (usbfs_positive(de)) {
355 spin_unlock(&dcache_lock);
356 return 0;
357 }
358 }
359
360 spin_unlock(&dcache_lock);
361 return 1;
362}
363
364static int usbfs_unlink (struct inode *dir, struct dentry *dentry)
365{
366 struct inode *inode = dentry->d_inode;
367 mutex_lock(&inode->i_mutex);
368 drop_nlink(dentry->d_inode);
369 dput(dentry);
370 mutex_unlock(&inode->i_mutex);
371 d_delete(dentry);
372 return 0;
373}
374
375static int usbfs_rmdir(struct inode *dir, struct dentry *dentry)
376{
377 int error = -ENOTEMPTY;
378 struct inode * inode = dentry->d_inode;
379
380 mutex_lock(&inode->i_mutex);
381 dentry_unhash(dentry);
382 if (usbfs_empty(dentry)) {
383 drop_nlink(dentry->d_inode);
384 drop_nlink(dentry->d_inode);
385 dput(dentry);
386 inode->i_flags |= S_DEAD;
387 drop_nlink(dir);
388 error = 0;
389 }
390 mutex_unlock(&inode->i_mutex);
391 if (!error)
392 d_delete(dentry);
393 dput(dentry);
394 return error;
395}
396
397
398
399static ssize_t default_read_file (struct file *file, char __user *buf,
400 size_t count, loff_t *ppos)
401{
402 return 0;
403}
404
405static ssize_t default_write_file (struct file *file, const char __user *buf,
406 size_t count, loff_t *ppos)
407{
408 return count;
409}
410
411static loff_t default_file_lseek (struct file *file, loff_t offset, int orig)
412{
413 loff_t retval = -EINVAL;
414
415 mutex_lock(&file->f_path.dentry->d_inode->i_mutex);
416 switch(orig) {
417 case 0:
418 if (offset > 0) {
419 file->f_pos = offset;
420 retval = file->f_pos;
421 }
422 break;
423 case 1:
424 if ((offset + file->f_pos) > 0) {
425 file->f_pos += offset;
426 retval = file->f_pos;
427 }
428 break;
429 default:
430 break;
431 }
432 mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
433 return retval;
434}
435
436static int default_open (struct inode *inode, struct file *file)
437{
438 if (inode->i_private)
439 file->private_data = inode->i_private;
440
441 return 0;
442}
443
444static const struct file_operations default_file_operations = {
445 .read = default_read_file,
446 .write = default_write_file,
447 .open = default_open,
448 .llseek = default_file_lseek,
449};
450
451static const struct super_operations usbfs_ops = {
452 .statfs = simple_statfs,
453 .drop_inode = generic_delete_inode,
454 .remount_fs = remount,
455 .show_options = usbfs_show_options,
456};
457
458static int usbfs_fill_super(struct super_block *sb, void *data, int silent)
459{
460 struct inode *inode;
461 struct dentry *root;
462
463 sb->s_blocksize = PAGE_CACHE_SIZE;
464 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
465 sb->s_magic = USBDEVICE_SUPER_MAGIC;
466 sb->s_op = &usbfs_ops;
467 sb->s_time_gran = 1;
468 inode = usbfs_get_inode(sb, S_IFDIR | 0755, 0);
469
470 if (!inode) {
471 dbg("%s: could not get inode!",__func__);
472 return -ENOMEM;
473 }
474
475 root = d_alloc_root(inode);
476 if (!root) {
477 dbg("%s: could not get root dentry!",__func__);
478 iput(inode);
479 return -ENOMEM;
480 }
481 sb->s_root = root;
482 return 0;
483}
484
485
486
487
488
489
490
491
492
493
494static int fs_create_by_name (const char *name, mode_t mode,
495 struct dentry *parent, struct dentry **dentry)
496{
497 int error = 0;
498
499
500
501
502
503
504 if (!parent ) {
505 if (usbfs_mount && usbfs_mount->mnt_sb) {
506 parent = usbfs_mount->mnt_sb->s_root;
507 }
508 }
509
510 if (!parent) {
511 dbg("Ah! can not find a parent!");
512 return -EFAULT;
513 }
514
515 *dentry = NULL;
516 mutex_lock(&parent->d_inode->i_mutex);
517 *dentry = lookup_one_len(name, parent, strlen(name));
518 if (!IS_ERR(dentry)) {
519 if ((mode & S_IFMT) == S_IFDIR)
520 error = usbfs_mkdir (parent->d_inode, *dentry, mode);
521 else
522 error = usbfs_create (parent->d_inode, *dentry, mode);
523 } else
524 error = PTR_ERR(dentry);
525 mutex_unlock(&parent->d_inode->i_mutex);
526
527 return error;
528}
529
530static struct dentry *fs_create_file (const char *name, mode_t mode,
531 struct dentry *parent, void *data,
532 const struct file_operations *fops,
533 uid_t uid, gid_t gid)
534{
535 struct dentry *dentry;
536 int error;
537
538 dbg("creating file '%s'",name);
539
540 error = fs_create_by_name (name, mode, parent, &dentry);
541 if (error) {
542 dentry = NULL;
543 } else {
544 if (dentry->d_inode) {
545 if (data)
546 dentry->d_inode->i_private = data;
547 if (fops)
548 dentry->d_inode->i_fop = fops;
549 dentry->d_inode->i_uid = uid;
550 dentry->d_inode->i_gid = gid;
551 }
552 }
553
554 return dentry;
555}
556
557static void fs_remove_file (struct dentry *dentry)
558{
559 struct dentry *parent = dentry->d_parent;
560
561 if (!parent || !parent->d_inode)
562 return;
563
564 mutex_lock_nested(&parent->d_inode->i_mutex, I_MUTEX_PARENT);
565 if (usbfs_positive(dentry)) {
566 if (dentry->d_inode) {
567 if (S_ISDIR(dentry->d_inode->i_mode))
568 usbfs_rmdir(parent->d_inode, dentry);
569 else
570 usbfs_unlink(parent->d_inode, dentry);
571 dput(dentry);
572 }
573 }
574 mutex_unlock(&parent->d_inode->i_mutex);
575}
576
577
578
579static int usb_get_sb(struct file_system_type *fs_type,
580 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
581{
582 return get_sb_single(fs_type, flags, data, usbfs_fill_super, mnt);
583}
584
585static struct file_system_type usb_fs_type = {
586 .owner = THIS_MODULE,
587 .name = "usbfs",
588 .get_sb = usb_get_sb,
589 .kill_sb = kill_litter_super,
590};
591
592
593
594static int create_special_files (void)
595{
596 struct dentry *parent;
597 int retval;
598
599
600
601
602 ignore_mount = 1;
603
604
605 retval = simple_pin_fs(&usb_fs_type, &usbfs_mount, &usbfs_mount_count);
606 if (retval) {
607 printk(KERN_ERR "Unable to get usbfs mount\n");
608 goto exit;
609 }
610
611 ignore_mount = 0;
612
613 parent = usbfs_mount->mnt_sb->s_root;
614 devices_usbfs_dentry = fs_create_file ("devices",
615 listmode | S_IFREG, parent,
616 NULL, &usbfs_devices_fops,
617 listuid, listgid);
618 if (devices_usbfs_dentry == NULL) {
619 printk(KERN_ERR "Unable to create devices usbfs file\n");
620 retval = -ENODEV;
621 goto error_clean_mounts;
622 }
623
624 goto exit;
625
626error_clean_mounts:
627 simple_release_fs(&usbfs_mount, &usbfs_mount_count);
628exit:
629 return retval;
630}
631
632static void remove_special_files (void)
633{
634 if (devices_usbfs_dentry)
635 fs_remove_file (devices_usbfs_dentry);
636 devices_usbfs_dentry = NULL;
637 simple_release_fs(&usbfs_mount, &usbfs_mount_count);
638}
639
640void usbfs_update_special (void)
641{
642 struct inode *inode;
643
644 if (devices_usbfs_dentry) {
645 inode = devices_usbfs_dentry->d_inode;
646 if (inode)
647 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
648 }
649}
650
651static void usbfs_add_bus(struct usb_bus *bus)
652{
653 struct dentry *parent;
654 char name[8];
655 int retval;
656
657
658 if (num_buses == 0) {
659 retval = create_special_files();
660 if (retval)
661 return;
662 }
663 ++num_buses;
664
665 sprintf (name, "%03d", bus->busnum);
666
667 parent = usbfs_mount->mnt_sb->s_root;
668 bus->usbfs_dentry = fs_create_file (name, busmode | S_IFDIR, parent,
669 bus, NULL, busuid, busgid);
670 if (bus->usbfs_dentry == NULL) {
671 printk(KERN_ERR "Error creating usbfs bus entry\n");
672 return;
673 }
674}
675
676static void usbfs_remove_bus(struct usb_bus *bus)
677{
678 if (bus->usbfs_dentry) {
679 fs_remove_file (bus->usbfs_dentry);
680 bus->usbfs_dentry = NULL;
681 }
682
683 --num_buses;
684 if (num_buses <= 0) {
685 remove_special_files();
686 num_buses = 0;
687 }
688}
689
690static void usbfs_add_device(struct usb_device *dev)
691{
692 char name[8];
693 int i;
694 int i_size;
695
696 sprintf (name, "%03d", dev->devnum);
697 dev->usbfs_dentry = fs_create_file (name, devmode | S_IFREG,
698 dev->bus->usbfs_dentry, dev,
699 &usbdev_file_operations,
700 devuid, devgid);
701 if (dev->usbfs_dentry == NULL) {
702 printk(KERN_ERR "Error creating usbfs device entry\n");
703 return;
704 }
705
706
707
708 i_size = sizeof (struct usb_device_descriptor);
709 for (i = 0; i < dev->descriptor.bNumConfigurations; ++i) {
710 struct usb_config_descriptor *config =
711 (struct usb_config_descriptor *)dev->rawdescriptors[i];
712 i_size += le16_to_cpu(config->wTotalLength);
713 }
714 if (dev->usbfs_dentry->d_inode)
715 dev->usbfs_dentry->d_inode->i_size = i_size;
716}
717
718static void usbfs_remove_device(struct usb_device *dev)
719{
720 if (dev->usbfs_dentry) {
721 fs_remove_file (dev->usbfs_dentry);
722 dev->usbfs_dentry = NULL;
723 }
724}
725
726static int usbfs_notify(struct notifier_block *self, unsigned long action, void *dev)
727{
728 switch (action) {
729 case USB_DEVICE_ADD:
730 usbfs_add_device(dev);
731 break;
732 case USB_DEVICE_REMOVE:
733 usbfs_remove_device(dev);
734 break;
735 case USB_BUS_ADD:
736 usbfs_add_bus(dev);
737 break;
738 case USB_BUS_REMOVE:
739 usbfs_remove_bus(dev);
740 }
741
742 usbfs_update_special();
743 usbfs_conn_disc_event();
744 return NOTIFY_OK;
745}
746
747static struct notifier_block usbfs_nb = {
748 .notifier_call = usbfs_notify,
749};
750
751
752
753static struct proc_dir_entry *usbdir = NULL;
754
755int __init usbfs_init(void)
756{
757 int retval;
758
759 retval = register_filesystem(&usb_fs_type);
760 if (retval)
761 return retval;
762
763 usb_register_notify(&usbfs_nb);
764
765
766 usbdir = proc_mkdir("bus/usb", NULL);
767
768 return 0;
769}
770
771void usbfs_cleanup(void)
772{
773 usb_unregister_notify(&usbfs_nb);
774 unregister_filesystem(&usb_fs_type);
775 if (usbdir)
776 remove_proc_entry("bus/usb", NULL);
777}
778
779
