1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (c) International Business Machines Corp., 2006 |
4 | * |
5 | * Author: Artem Bityutskiy (Битюцкий Артём) |
6 | */ |
7 | |
8 | /* |
9 | * This file includes implementation of UBI character device operations. |
10 | * |
11 | * There are two kinds of character devices in UBI: UBI character devices and |
12 | * UBI volume character devices. UBI character devices allow users to |
13 | * manipulate whole volumes: create, remove, and re-size them. Volume character |
14 | * devices provide volume I/O capabilities. |
15 | * |
16 | * Major and minor numbers are assigned dynamically to both UBI and volume |
17 | * character devices. |
18 | * |
19 | * Well, there is the third kind of character devices - the UBI control |
20 | * character device, which allows to manipulate by UBI devices - create and |
21 | * delete them. In other words, it is used for attaching and detaching MTD |
22 | * devices. |
23 | */ |
24 | |
25 | #include <linux/module.h> |
26 | #include <linux/stat.h> |
27 | #include <linux/slab.h> |
28 | #include <linux/ioctl.h> |
29 | #include <linux/capability.h> |
30 | #include <linux/uaccess.h> |
31 | #include <linux/compat.h> |
32 | #include <linux/math64.h> |
33 | #include <mtd/ubi-user.h> |
34 | #include "ubi.h" |
35 | |
36 | /** |
37 | * get_exclusive - get exclusive access to an UBI volume. |
38 | * @desc: volume descriptor |
39 | * |
40 | * This function changes UBI volume open mode to "exclusive". Returns previous |
41 | * mode value (positive integer) in case of success and a negative error code |
42 | * in case of failure. |
43 | */ |
44 | static int get_exclusive(struct ubi_volume_desc *desc) |
45 | { |
46 | int users, err; |
47 | struct ubi_volume *vol = desc->vol; |
48 | |
49 | spin_lock(lock: &vol->ubi->volumes_lock); |
50 | users = vol->readers + vol->writers + vol->exclusive + vol->metaonly; |
51 | ubi_assert(users > 0); |
52 | if (users > 1) { |
53 | ubi_err(ubi: vol->ubi, fmt: "%d users for volume %d" , users, vol->vol_id); |
54 | err = -EBUSY; |
55 | } else { |
56 | vol->readers = vol->writers = vol->metaonly = 0; |
57 | vol->exclusive = 1; |
58 | err = desc->mode; |
59 | desc->mode = UBI_EXCLUSIVE; |
60 | } |
61 | spin_unlock(lock: &vol->ubi->volumes_lock); |
62 | |
63 | return err; |
64 | } |
65 | |
66 | /** |
67 | * revoke_exclusive - revoke exclusive mode. |
68 | * @desc: volume descriptor |
69 | * @mode: new mode to switch to |
70 | */ |
71 | static void revoke_exclusive(struct ubi_volume_desc *desc, int mode) |
72 | { |
73 | struct ubi_volume *vol = desc->vol; |
74 | |
75 | spin_lock(lock: &vol->ubi->volumes_lock); |
76 | ubi_assert(vol->readers == 0 && vol->writers == 0 && vol->metaonly == 0); |
77 | ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE); |
78 | vol->exclusive = 0; |
79 | if (mode == UBI_READONLY) |
80 | vol->readers = 1; |
81 | else if (mode == UBI_READWRITE) |
82 | vol->writers = 1; |
83 | else if (mode == UBI_METAONLY) |
84 | vol->metaonly = 1; |
85 | else |
86 | vol->exclusive = 1; |
87 | spin_unlock(lock: &vol->ubi->volumes_lock); |
88 | |
89 | desc->mode = mode; |
90 | } |
91 | |
92 | static int vol_cdev_open(struct inode *inode, struct file *file) |
93 | { |
94 | struct ubi_volume_desc *desc; |
95 | int vol_id = iminor(inode) - 1, mode, ubi_num; |
96 | |
97 | ubi_num = ubi_major2num(major: imajor(inode)); |
98 | if (ubi_num < 0) |
99 | return ubi_num; |
100 | |
101 | if (file->f_mode & FMODE_WRITE) |
102 | mode = UBI_READWRITE; |
103 | else |
104 | mode = UBI_READONLY; |
105 | |
106 | dbg_gen("open device %d, volume %d, mode %d" , |
107 | ubi_num, vol_id, mode); |
108 | |
109 | desc = ubi_open_volume(ubi_num, vol_id, mode); |
110 | if (IS_ERR(ptr: desc)) |
111 | return PTR_ERR(ptr: desc); |
112 | |
113 | file->private_data = desc; |
114 | return 0; |
115 | } |
116 | |
117 | static int vol_cdev_release(struct inode *inode, struct file *file) |
118 | { |
119 | struct ubi_volume_desc *desc = file->private_data; |
120 | struct ubi_volume *vol = desc->vol; |
121 | |
122 | dbg_gen("release device %d, volume %d, mode %d" , |
123 | vol->ubi->ubi_num, vol->vol_id, desc->mode); |
124 | |
125 | if (vol->updating) { |
126 | ubi_warn(ubi: vol->ubi, fmt: "update of volume %d not finished, volume is damaged" , |
127 | vol->vol_id); |
128 | ubi_assert(!vol->changing_leb); |
129 | vol->updating = 0; |
130 | vfree(addr: vol->upd_buf); |
131 | } else if (vol->changing_leb) { |
132 | dbg_gen("only %lld of %lld bytes received for atomic LEB change for volume %d:%d, cancel" , |
133 | vol->upd_received, vol->upd_bytes, vol->ubi->ubi_num, |
134 | vol->vol_id); |
135 | vol->changing_leb = 0; |
136 | vfree(addr: vol->upd_buf); |
137 | } |
138 | |
139 | ubi_close_volume(desc); |
140 | return 0; |
141 | } |
142 | |
143 | static loff_t vol_cdev_llseek(struct file *file, loff_t offset, int origin) |
144 | { |
145 | struct ubi_volume_desc *desc = file->private_data; |
146 | struct ubi_volume *vol = desc->vol; |
147 | |
148 | if (vol->updating) { |
149 | /* Update is in progress, seeking is prohibited */ |
150 | ubi_err(ubi: vol->ubi, fmt: "updating" ); |
151 | return -EBUSY; |
152 | } |
153 | |
154 | return fixed_size_llseek(file, offset, whence: origin, size: vol->used_bytes); |
155 | } |
156 | |
157 | static int vol_cdev_fsync(struct file *file, loff_t start, loff_t end, |
158 | int datasync) |
159 | { |
160 | struct ubi_volume_desc *desc = file->private_data; |
161 | struct ubi_device *ubi = desc->vol->ubi; |
162 | struct inode *inode = file_inode(f: file); |
163 | int err; |
164 | inode_lock(inode); |
165 | err = ubi_sync(ubi_num: ubi->ubi_num); |
166 | inode_unlock(inode); |
167 | return err; |
168 | } |
169 | |
170 | |
171 | static ssize_t vol_cdev_read(struct file *file, __user char *buf, size_t count, |
172 | loff_t *offp) |
173 | { |
174 | struct ubi_volume_desc *desc = file->private_data; |
175 | struct ubi_volume *vol = desc->vol; |
176 | struct ubi_device *ubi = vol->ubi; |
177 | int err, lnum, off, len, tbuf_size; |
178 | size_t count_save = count; |
179 | void *tbuf; |
180 | |
181 | dbg_gen("read %zd bytes from offset %lld of volume %d" , |
182 | count, *offp, vol->vol_id); |
183 | |
184 | if (vol->updating) { |
185 | ubi_err(ubi: vol->ubi, fmt: "updating" ); |
186 | return -EBUSY; |
187 | } |
188 | if (vol->upd_marker) { |
189 | ubi_err(ubi: vol->ubi, fmt: "damaged volume, update marker is set" ); |
190 | return -EBADF; |
191 | } |
192 | if (*offp == vol->used_bytes || count == 0) |
193 | return 0; |
194 | |
195 | if (vol->corrupted) |
196 | dbg_gen("read from corrupted volume %d" , vol->vol_id); |
197 | |
198 | if (*offp + count > vol->used_bytes) |
199 | count_save = count = vol->used_bytes - *offp; |
200 | |
201 | tbuf_size = vol->usable_leb_size; |
202 | if (count < tbuf_size) |
203 | tbuf_size = ALIGN(count, ubi->min_io_size); |
204 | tbuf = vmalloc(size: tbuf_size); |
205 | if (!tbuf) |
206 | return -ENOMEM; |
207 | |
208 | len = count > tbuf_size ? tbuf_size : count; |
209 | lnum = div_u64_rem(dividend: *offp, divisor: vol->usable_leb_size, remainder: &off); |
210 | |
211 | do { |
212 | cond_resched(); |
213 | |
214 | if (off + len >= vol->usable_leb_size) |
215 | len = vol->usable_leb_size - off; |
216 | |
217 | err = ubi_eba_read_leb(ubi, vol, lnum, buf: tbuf, offset: off, len, check: 0); |
218 | if (err) |
219 | break; |
220 | |
221 | off += len; |
222 | if (off == vol->usable_leb_size) { |
223 | lnum += 1; |
224 | off -= vol->usable_leb_size; |
225 | } |
226 | |
227 | count -= len; |
228 | *offp += len; |
229 | |
230 | err = copy_to_user(to: buf, from: tbuf, n: len); |
231 | if (err) { |
232 | err = -EFAULT; |
233 | break; |
234 | } |
235 | |
236 | buf += len; |
237 | len = count > tbuf_size ? tbuf_size : count; |
238 | } while (count); |
239 | |
240 | vfree(addr: tbuf); |
241 | return err ? err : count_save - count; |
242 | } |
243 | |
244 | /* |
245 | * This function allows to directly write to dynamic UBI volumes, without |
246 | * issuing the volume update operation. |
247 | */ |
248 | static ssize_t vol_cdev_direct_write(struct file *file, const char __user *buf, |
249 | size_t count, loff_t *offp) |
250 | { |
251 | struct ubi_volume_desc *desc = file->private_data; |
252 | struct ubi_volume *vol = desc->vol; |
253 | struct ubi_device *ubi = vol->ubi; |
254 | int lnum, off, len, tbuf_size, err = 0; |
255 | size_t count_save = count; |
256 | char *tbuf; |
257 | |
258 | if (!vol->direct_writes) |
259 | return -EPERM; |
260 | |
261 | dbg_gen("requested: write %zd bytes to offset %lld of volume %u" , |
262 | count, *offp, vol->vol_id); |
263 | |
264 | if (vol->vol_type == UBI_STATIC_VOLUME) |
265 | return -EROFS; |
266 | |
267 | lnum = div_u64_rem(dividend: *offp, divisor: vol->usable_leb_size, remainder: &off); |
268 | if (off & (ubi->min_io_size - 1)) { |
269 | ubi_err(ubi, fmt: "unaligned position" ); |
270 | return -EINVAL; |
271 | } |
272 | |
273 | if (*offp + count > vol->used_bytes) |
274 | count_save = count = vol->used_bytes - *offp; |
275 | |
276 | /* We can write only in fractions of the minimum I/O unit */ |
277 | if (count & (ubi->min_io_size - 1)) { |
278 | ubi_err(ubi, fmt: "unaligned write length" ); |
279 | return -EINVAL; |
280 | } |
281 | |
282 | tbuf_size = vol->usable_leb_size; |
283 | if (count < tbuf_size) |
284 | tbuf_size = ALIGN(count, ubi->min_io_size); |
285 | tbuf = vmalloc(size: tbuf_size); |
286 | if (!tbuf) |
287 | return -ENOMEM; |
288 | |
289 | len = count > tbuf_size ? tbuf_size : count; |
290 | |
291 | while (count) { |
292 | cond_resched(); |
293 | |
294 | if (off + len >= vol->usable_leb_size) |
295 | len = vol->usable_leb_size - off; |
296 | |
297 | err = copy_from_user(to: tbuf, from: buf, n: len); |
298 | if (err) { |
299 | err = -EFAULT; |
300 | break; |
301 | } |
302 | |
303 | err = ubi_eba_write_leb(ubi, vol, lnum, buf: tbuf, offset: off, len); |
304 | if (err) |
305 | break; |
306 | |
307 | off += len; |
308 | if (off == vol->usable_leb_size) { |
309 | lnum += 1; |
310 | off -= vol->usable_leb_size; |
311 | } |
312 | |
313 | count -= len; |
314 | *offp += len; |
315 | buf += len; |
316 | len = count > tbuf_size ? tbuf_size : count; |
317 | } |
318 | |
319 | vfree(addr: tbuf); |
320 | return err ? err : count_save - count; |
321 | } |
322 | |
323 | static ssize_t vol_cdev_write(struct file *file, const char __user *buf, |
324 | size_t count, loff_t *offp) |
325 | { |
326 | int err = 0; |
327 | struct ubi_volume_desc *desc = file->private_data; |
328 | struct ubi_volume *vol = desc->vol; |
329 | struct ubi_device *ubi = vol->ubi; |
330 | |
331 | if (!vol->updating && !vol->changing_leb) |
332 | return vol_cdev_direct_write(file, buf, count, offp); |
333 | |
334 | if (vol->updating) |
335 | err = ubi_more_update_data(ubi, vol, buf, count); |
336 | else |
337 | err = ubi_more_leb_change_data(ubi, vol, buf, count); |
338 | |
339 | if (err < 0) { |
340 | ubi_err(ubi, fmt: "cannot accept more %zd bytes of data, error %d" , |
341 | count, err); |
342 | return err; |
343 | } |
344 | |
345 | if (err) { |
346 | /* |
347 | * The operation is finished, @err contains number of actually |
348 | * written bytes. |
349 | */ |
350 | count = err; |
351 | |
352 | if (vol->changing_leb) { |
353 | revoke_exclusive(desc, mode: UBI_READWRITE); |
354 | return count; |
355 | } |
356 | |
357 | /* |
358 | * We voluntarily do not take into account the skip_check flag |
359 | * as we want to make sure what we wrote was correctly written. |
360 | */ |
361 | err = ubi_check_volume(ubi, vol_id: vol->vol_id); |
362 | if (err < 0) |
363 | return err; |
364 | |
365 | if (err) { |
366 | ubi_warn(ubi, fmt: "volume %d on UBI device %d is corrupted" , |
367 | vol->vol_id, ubi->ubi_num); |
368 | vol->corrupted = 1; |
369 | } |
370 | vol->checked = 1; |
371 | ubi_volume_notify(ubi, vol, ntype: UBI_VOLUME_UPDATED); |
372 | revoke_exclusive(desc, mode: UBI_READWRITE); |
373 | } |
374 | |
375 | return count; |
376 | } |
377 | |
378 | static long vol_cdev_ioctl(struct file *file, unsigned int cmd, |
379 | unsigned long arg) |
380 | { |
381 | int err = 0; |
382 | struct ubi_volume_desc *desc = file->private_data; |
383 | struct ubi_volume *vol = desc->vol; |
384 | struct ubi_device *ubi = vol->ubi; |
385 | void __user *argp = (void __user *)arg; |
386 | |
387 | switch (cmd) { |
388 | /* Volume update command */ |
389 | case UBI_IOCVOLUP: |
390 | { |
391 | int64_t bytes, rsvd_bytes; |
392 | |
393 | if (!capable(CAP_SYS_RESOURCE)) { |
394 | err = -EPERM; |
395 | break; |
396 | } |
397 | |
398 | err = copy_from_user(to: &bytes, from: argp, n: sizeof(int64_t)); |
399 | if (err) { |
400 | err = -EFAULT; |
401 | break; |
402 | } |
403 | |
404 | if (desc->mode == UBI_READONLY) { |
405 | err = -EROFS; |
406 | break; |
407 | } |
408 | |
409 | rsvd_bytes = (long long)vol->reserved_pebs * |
410 | vol->usable_leb_size; |
411 | if (bytes < 0 || bytes > rsvd_bytes) { |
412 | err = -EINVAL; |
413 | break; |
414 | } |
415 | |
416 | err = get_exclusive(desc); |
417 | if (err < 0) |
418 | break; |
419 | |
420 | err = ubi_start_update(ubi, vol, bytes); |
421 | if (bytes == 0) { |
422 | ubi_volume_notify(ubi, vol, ntype: UBI_VOLUME_UPDATED); |
423 | revoke_exclusive(desc, mode: UBI_READWRITE); |
424 | } |
425 | break; |
426 | } |
427 | |
428 | /* Atomic logical eraseblock change command */ |
429 | case UBI_IOCEBCH: |
430 | { |
431 | struct ubi_leb_change_req req; |
432 | |
433 | err = copy_from_user(to: &req, from: argp, |
434 | n: sizeof(struct ubi_leb_change_req)); |
435 | if (err) { |
436 | err = -EFAULT; |
437 | break; |
438 | } |
439 | |
440 | if (desc->mode == UBI_READONLY || |
441 | vol->vol_type == UBI_STATIC_VOLUME) { |
442 | err = -EROFS; |
443 | break; |
444 | } |
445 | |
446 | /* Validate the request */ |
447 | err = -EINVAL; |
448 | if (!ubi_leb_valid(vol, lnum: req.lnum) || |
449 | req.bytes < 0 || req.bytes > vol->usable_leb_size) |
450 | break; |
451 | |
452 | err = get_exclusive(desc); |
453 | if (err < 0) |
454 | break; |
455 | |
456 | err = ubi_start_leb_change(ubi, vol, req: &req); |
457 | if (req.bytes == 0) |
458 | revoke_exclusive(desc, mode: UBI_READWRITE); |
459 | break; |
460 | } |
461 | |
462 | /* Logical eraseblock erasure command */ |
463 | case UBI_IOCEBER: |
464 | { |
465 | int32_t lnum; |
466 | |
467 | err = get_user(lnum, (__user int32_t *)argp); |
468 | if (err) { |
469 | err = -EFAULT; |
470 | break; |
471 | } |
472 | |
473 | if (desc->mode == UBI_READONLY || |
474 | vol->vol_type == UBI_STATIC_VOLUME) { |
475 | err = -EROFS; |
476 | break; |
477 | } |
478 | |
479 | if (!ubi_leb_valid(vol, lnum)) { |
480 | err = -EINVAL; |
481 | break; |
482 | } |
483 | |
484 | dbg_gen("erase LEB %d:%d" , vol->vol_id, lnum); |
485 | err = ubi_eba_unmap_leb(ubi, vol, lnum); |
486 | if (err) |
487 | break; |
488 | |
489 | err = ubi_wl_flush(ubi, UBI_ALL, UBI_ALL); |
490 | break; |
491 | } |
492 | |
493 | /* Logical eraseblock map command */ |
494 | case UBI_IOCEBMAP: |
495 | { |
496 | struct ubi_map_req req; |
497 | |
498 | err = copy_from_user(to: &req, from: argp, n: sizeof(struct ubi_map_req)); |
499 | if (err) { |
500 | err = -EFAULT; |
501 | break; |
502 | } |
503 | err = ubi_leb_map(desc, lnum: req.lnum); |
504 | break; |
505 | } |
506 | |
507 | /* Logical eraseblock un-map command */ |
508 | case UBI_IOCEBUNMAP: |
509 | { |
510 | int32_t lnum; |
511 | |
512 | err = get_user(lnum, (__user int32_t *)argp); |
513 | if (err) { |
514 | err = -EFAULT; |
515 | break; |
516 | } |
517 | err = ubi_leb_unmap(desc, lnum); |
518 | break; |
519 | } |
520 | |
521 | /* Check if logical eraseblock is mapped command */ |
522 | case UBI_IOCEBISMAP: |
523 | { |
524 | int32_t lnum; |
525 | |
526 | err = get_user(lnum, (__user int32_t *)argp); |
527 | if (err) { |
528 | err = -EFAULT; |
529 | break; |
530 | } |
531 | err = ubi_is_mapped(desc, lnum); |
532 | break; |
533 | } |
534 | |
535 | /* Set volume property command */ |
536 | case UBI_IOCSETVOLPROP: |
537 | { |
538 | struct ubi_set_vol_prop_req req; |
539 | |
540 | err = copy_from_user(to: &req, from: argp, |
541 | n: sizeof(struct ubi_set_vol_prop_req)); |
542 | if (err) { |
543 | err = -EFAULT; |
544 | break; |
545 | } |
546 | switch (req.property) { |
547 | case UBI_VOL_PROP_DIRECT_WRITE: |
548 | mutex_lock(&ubi->device_mutex); |
549 | desc->vol->direct_writes = !!req.value; |
550 | mutex_unlock(lock: &ubi->device_mutex); |
551 | break; |
552 | default: |
553 | err = -EINVAL; |
554 | break; |
555 | } |
556 | break; |
557 | } |
558 | |
559 | /* Create a R/O block device on top of the UBI volume */ |
560 | case UBI_IOCVOLCRBLK: |
561 | { |
562 | struct ubi_volume_info vi; |
563 | |
564 | ubi_get_volume_info(desc, vi: &vi); |
565 | err = ubiblock_create(vi: &vi); |
566 | break; |
567 | } |
568 | |
569 | /* Remove the R/O block device */ |
570 | case UBI_IOCVOLRMBLK: |
571 | { |
572 | struct ubi_volume_info vi; |
573 | |
574 | ubi_get_volume_info(desc, vi: &vi); |
575 | err = ubiblock_remove(vi: &vi); |
576 | break; |
577 | } |
578 | |
579 | default: |
580 | err = -ENOTTY; |
581 | break; |
582 | } |
583 | return err; |
584 | } |
585 | |
586 | /** |
587 | * verify_mkvol_req - verify volume creation request. |
588 | * @ubi: UBI device description object |
589 | * @req: the request to check |
590 | * |
591 | * This function zero if the request is correct, and %-EINVAL if not. |
592 | */ |
593 | static int verify_mkvol_req(const struct ubi_device *ubi, |
594 | const struct ubi_mkvol_req *req) |
595 | { |
596 | int n, err = -EINVAL; |
597 | |
598 | if (req->bytes < 0 || req->alignment < 0 || req->vol_type < 0 || |
599 | req->name_len < 0) |
600 | goto bad; |
601 | |
602 | if ((req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) && |
603 | req->vol_id != UBI_VOL_NUM_AUTO) |
604 | goto bad; |
605 | |
606 | if (req->alignment == 0) |
607 | goto bad; |
608 | |
609 | if (req->bytes == 0) |
610 | goto bad; |
611 | |
612 | if (req->vol_type != UBI_DYNAMIC_VOLUME && |
613 | req->vol_type != UBI_STATIC_VOLUME) |
614 | goto bad; |
615 | |
616 | if (req->flags & ~UBI_VOL_VALID_FLGS) |
617 | goto bad; |
618 | |
619 | if (req->flags & UBI_VOL_SKIP_CRC_CHECK_FLG && |
620 | req->vol_type != UBI_STATIC_VOLUME) |
621 | goto bad; |
622 | |
623 | if (req->alignment > ubi->leb_size) |
624 | goto bad; |
625 | |
626 | n = req->alignment & (ubi->min_io_size - 1); |
627 | if (req->alignment != 1 && n) |
628 | goto bad; |
629 | |
630 | if (!req->name[0] || !req->name_len) |
631 | goto bad; |
632 | |
633 | if (req->name_len > UBI_VOL_NAME_MAX) { |
634 | err = -ENAMETOOLONG; |
635 | goto bad; |
636 | } |
637 | |
638 | n = strnlen(p: req->name, maxlen: req->name_len + 1); |
639 | if (n != req->name_len) |
640 | goto bad; |
641 | |
642 | return 0; |
643 | |
644 | bad: |
645 | ubi_err(ubi, fmt: "bad volume creation request" ); |
646 | ubi_dump_mkvol_req(req); |
647 | return err; |
648 | } |
649 | |
650 | /** |
651 | * verify_rsvol_req - verify volume re-size request. |
652 | * @ubi: UBI device description object |
653 | * @req: the request to check |
654 | * |
655 | * This function returns zero if the request is correct, and %-EINVAL if not. |
656 | */ |
657 | static int verify_rsvol_req(const struct ubi_device *ubi, |
658 | const struct ubi_rsvol_req *req) |
659 | { |
660 | if (req->bytes <= 0) |
661 | return -EINVAL; |
662 | |
663 | if (req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) |
664 | return -EINVAL; |
665 | |
666 | return 0; |
667 | } |
668 | |
669 | /** |
670 | * rename_volumes - rename UBI volumes. |
671 | * @ubi: UBI device description object |
672 | * @req: volumes re-name request |
673 | * |
674 | * This is a helper function for the volume re-name IOCTL which validates the |
675 | * request, opens the volume and calls corresponding volumes management |
676 | * function. Returns zero in case of success and a negative error code in case |
677 | * of failure. |
678 | */ |
679 | static int rename_volumes(struct ubi_device *ubi, |
680 | struct ubi_rnvol_req *req) |
681 | { |
682 | int i, n, err; |
683 | struct list_head rename_list; |
684 | struct ubi_rename_entry *re, *re1; |
685 | |
686 | if (req->count < 0 || req->count > UBI_MAX_RNVOL) |
687 | return -EINVAL; |
688 | |
689 | if (req->count == 0) |
690 | return 0; |
691 | |
692 | /* Validate volume IDs and names in the request */ |
693 | for (i = 0; i < req->count; i++) { |
694 | if (req->ents[i].vol_id < 0 || |
695 | req->ents[i].vol_id >= ubi->vtbl_slots) |
696 | return -EINVAL; |
697 | if (req->ents[i].name_len < 0) |
698 | return -EINVAL; |
699 | if (req->ents[i].name_len > UBI_VOL_NAME_MAX) |
700 | return -ENAMETOOLONG; |
701 | req->ents[i].name[req->ents[i].name_len] = '\0'; |
702 | n = strlen(req->ents[i].name); |
703 | if (n != req->ents[i].name_len) |
704 | return -EINVAL; |
705 | } |
706 | |
707 | /* Make sure volume IDs and names are unique */ |
708 | for (i = 0; i < req->count - 1; i++) { |
709 | for (n = i + 1; n < req->count; n++) { |
710 | if (req->ents[i].vol_id == req->ents[n].vol_id) { |
711 | ubi_err(ubi, fmt: "duplicated volume id %d" , |
712 | req->ents[i].vol_id); |
713 | return -EINVAL; |
714 | } |
715 | if (!strcmp(req->ents[i].name, req->ents[n].name)) { |
716 | ubi_err(ubi, fmt: "duplicated volume name \"%s\"" , |
717 | req->ents[i].name); |
718 | return -EINVAL; |
719 | } |
720 | } |
721 | } |
722 | |
723 | /* Create the re-name list */ |
724 | INIT_LIST_HEAD(list: &rename_list); |
725 | for (i = 0; i < req->count; i++) { |
726 | int vol_id = req->ents[i].vol_id; |
727 | int name_len = req->ents[i].name_len; |
728 | const char *name = req->ents[i].name; |
729 | |
730 | re = kzalloc(size: sizeof(struct ubi_rename_entry), GFP_KERNEL); |
731 | if (!re) { |
732 | err = -ENOMEM; |
733 | goto out_free; |
734 | } |
735 | |
736 | re->desc = ubi_open_volume(ubi_num: ubi->ubi_num, vol_id, mode: UBI_METAONLY); |
737 | if (IS_ERR(ptr: re->desc)) { |
738 | err = PTR_ERR(ptr: re->desc); |
739 | ubi_err(ubi, fmt: "cannot open volume %d, error %d" , |
740 | vol_id, err); |
741 | kfree(objp: re); |
742 | goto out_free; |
743 | } |
744 | |
745 | /* Skip this re-naming if the name does not really change */ |
746 | if (re->desc->vol->name_len == name_len && |
747 | !memcmp(p: re->desc->vol->name, q: name, size: name_len)) { |
748 | ubi_close_volume(desc: re->desc); |
749 | kfree(objp: re); |
750 | continue; |
751 | } |
752 | |
753 | re->new_name_len = name_len; |
754 | memcpy(re->new_name, name, name_len); |
755 | list_add_tail(new: &re->list, head: &rename_list); |
756 | dbg_gen("will rename volume %d from \"%s\" to \"%s\"" , |
757 | vol_id, re->desc->vol->name, name); |
758 | } |
759 | |
760 | if (list_empty(head: &rename_list)) |
761 | return 0; |
762 | |
763 | /* Find out the volumes which have to be removed */ |
764 | list_for_each_entry(re, &rename_list, list) { |
765 | struct ubi_volume_desc *desc; |
766 | int no_remove_needed = 0; |
767 | |
768 | /* |
769 | * Volume @re->vol_id is going to be re-named to |
770 | * @re->new_name, while its current name is @name. If a volume |
771 | * with name @re->new_name currently exists, it has to be |
772 | * removed, unless it is also re-named in the request (@req). |
773 | */ |
774 | list_for_each_entry(re1, &rename_list, list) { |
775 | if (re->new_name_len == re1->desc->vol->name_len && |
776 | !memcmp(p: re->new_name, q: re1->desc->vol->name, |
777 | size: re1->desc->vol->name_len)) { |
778 | no_remove_needed = 1; |
779 | break; |
780 | } |
781 | } |
782 | |
783 | if (no_remove_needed) |
784 | continue; |
785 | |
786 | /* |
787 | * It seems we need to remove volume with name @re->new_name, |
788 | * if it exists. |
789 | */ |
790 | desc = ubi_open_volume_nm(ubi_num: ubi->ubi_num, name: re->new_name, |
791 | mode: UBI_EXCLUSIVE); |
792 | if (IS_ERR(ptr: desc)) { |
793 | err = PTR_ERR(ptr: desc); |
794 | if (err == -ENODEV) |
795 | /* Re-naming into a non-existing volume name */ |
796 | continue; |
797 | |
798 | /* The volume exists but busy, or an error occurred */ |
799 | ubi_err(ubi, fmt: "cannot open volume \"%s\", error %d" , |
800 | re->new_name, err); |
801 | goto out_free; |
802 | } |
803 | |
804 | re1 = kzalloc(size: sizeof(struct ubi_rename_entry), GFP_KERNEL); |
805 | if (!re1) { |
806 | err = -ENOMEM; |
807 | ubi_close_volume(desc); |
808 | goto out_free; |
809 | } |
810 | |
811 | re1->remove = 1; |
812 | re1->desc = desc; |
813 | list_add(new: &re1->list, head: &rename_list); |
814 | dbg_gen("will remove volume %d, name \"%s\"" , |
815 | re1->desc->vol->vol_id, re1->desc->vol->name); |
816 | } |
817 | |
818 | mutex_lock(&ubi->device_mutex); |
819 | err = ubi_rename_volumes(ubi, rename_list: &rename_list); |
820 | mutex_unlock(lock: &ubi->device_mutex); |
821 | |
822 | out_free: |
823 | list_for_each_entry_safe(re, re1, &rename_list, list) { |
824 | ubi_close_volume(desc: re->desc); |
825 | list_del(entry: &re->list); |
826 | kfree(objp: re); |
827 | } |
828 | return err; |
829 | } |
830 | |
831 | static long ubi_cdev_ioctl(struct file *file, unsigned int cmd, |
832 | unsigned long arg) |
833 | { |
834 | int err = 0; |
835 | struct ubi_device *ubi; |
836 | struct ubi_volume_desc *desc; |
837 | void __user *argp = (void __user *)arg; |
838 | |
839 | if (!capable(CAP_SYS_RESOURCE)) |
840 | return -EPERM; |
841 | |
842 | ubi = ubi_get_by_major(major: imajor(inode: file->f_mapping->host)); |
843 | if (!ubi) |
844 | return -ENODEV; |
845 | |
846 | switch (cmd) { |
847 | /* Create volume command */ |
848 | case UBI_IOCMKVOL: |
849 | { |
850 | struct ubi_mkvol_req req; |
851 | |
852 | dbg_gen("create volume" ); |
853 | err = copy_from_user(to: &req, from: argp, n: sizeof(struct ubi_mkvol_req)); |
854 | if (err) { |
855 | err = -EFAULT; |
856 | break; |
857 | } |
858 | |
859 | err = verify_mkvol_req(ubi, req: &req); |
860 | if (err) |
861 | break; |
862 | |
863 | mutex_lock(&ubi->device_mutex); |
864 | err = ubi_create_volume(ubi, req: &req); |
865 | mutex_unlock(lock: &ubi->device_mutex); |
866 | if (err) |
867 | break; |
868 | |
869 | err = put_user(req.vol_id, (__user int32_t *)argp); |
870 | if (err) |
871 | err = -EFAULT; |
872 | |
873 | break; |
874 | } |
875 | |
876 | /* Remove volume command */ |
877 | case UBI_IOCRMVOL: |
878 | { |
879 | int vol_id; |
880 | |
881 | dbg_gen("remove volume" ); |
882 | err = get_user(vol_id, (__user int32_t *)argp); |
883 | if (err) { |
884 | err = -EFAULT; |
885 | break; |
886 | } |
887 | |
888 | desc = ubi_open_volume(ubi_num: ubi->ubi_num, vol_id, mode: UBI_EXCLUSIVE); |
889 | if (IS_ERR(ptr: desc)) { |
890 | err = PTR_ERR(ptr: desc); |
891 | break; |
892 | } |
893 | |
894 | mutex_lock(&ubi->device_mutex); |
895 | err = ubi_remove_volume(desc, no_vtbl: 0); |
896 | mutex_unlock(lock: &ubi->device_mutex); |
897 | |
898 | /* |
899 | * The volume is deleted (unless an error occurred), and the |
900 | * 'struct ubi_volume' object will be freed when |
901 | * 'ubi_close_volume()' will call 'put_device()'. |
902 | */ |
903 | ubi_close_volume(desc); |
904 | break; |
905 | } |
906 | |
907 | /* Re-size volume command */ |
908 | case UBI_IOCRSVOL: |
909 | { |
910 | int pebs; |
911 | struct ubi_rsvol_req req; |
912 | |
913 | dbg_gen("re-size volume" ); |
914 | err = copy_from_user(to: &req, from: argp, n: sizeof(struct ubi_rsvol_req)); |
915 | if (err) { |
916 | err = -EFAULT; |
917 | break; |
918 | } |
919 | |
920 | err = verify_rsvol_req(ubi, req: &req); |
921 | if (err) |
922 | break; |
923 | |
924 | desc = ubi_open_volume(ubi_num: ubi->ubi_num, vol_id: req.vol_id, mode: UBI_EXCLUSIVE); |
925 | if (IS_ERR(ptr: desc)) { |
926 | err = PTR_ERR(ptr: desc); |
927 | break; |
928 | } |
929 | |
930 | pebs = div_u64(dividend: req.bytes + desc->vol->usable_leb_size - 1, |
931 | divisor: desc->vol->usable_leb_size); |
932 | |
933 | mutex_lock(&ubi->device_mutex); |
934 | err = ubi_resize_volume(desc, reserved_pebs: pebs); |
935 | mutex_unlock(lock: &ubi->device_mutex); |
936 | ubi_close_volume(desc); |
937 | break; |
938 | } |
939 | |
940 | /* Re-name volumes command */ |
941 | case UBI_IOCRNVOL: |
942 | { |
943 | struct ubi_rnvol_req *req; |
944 | |
945 | dbg_gen("re-name volumes" ); |
946 | req = kmalloc(size: sizeof(struct ubi_rnvol_req), GFP_KERNEL); |
947 | if (!req) { |
948 | err = -ENOMEM; |
949 | break; |
950 | } |
951 | |
952 | err = copy_from_user(to: req, from: argp, n: sizeof(struct ubi_rnvol_req)); |
953 | if (err) { |
954 | err = -EFAULT; |
955 | kfree(objp: req); |
956 | break; |
957 | } |
958 | |
959 | err = rename_volumes(ubi, req); |
960 | kfree(objp: req); |
961 | break; |
962 | } |
963 | |
964 | /* Check a specific PEB for bitflips and scrub it if needed */ |
965 | case UBI_IOCRPEB: |
966 | { |
967 | int pnum; |
968 | |
969 | err = get_user(pnum, (__user int32_t *)argp); |
970 | if (err) { |
971 | err = -EFAULT; |
972 | break; |
973 | } |
974 | |
975 | err = ubi_bitflip_check(ubi, pnum, force_scrub: 0); |
976 | break; |
977 | } |
978 | |
979 | /* Force scrubbing for a specific PEB */ |
980 | case UBI_IOCSPEB: |
981 | { |
982 | int pnum; |
983 | |
984 | err = get_user(pnum, (__user int32_t *)argp); |
985 | if (err) { |
986 | err = -EFAULT; |
987 | break; |
988 | } |
989 | |
990 | err = ubi_bitflip_check(ubi, pnum, force_scrub: 1); |
991 | break; |
992 | } |
993 | |
994 | default: |
995 | err = -ENOTTY; |
996 | break; |
997 | } |
998 | |
999 | ubi_put_device(ubi); |
1000 | return err; |
1001 | } |
1002 | |
1003 | static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd, |
1004 | unsigned long arg) |
1005 | { |
1006 | int err = 0; |
1007 | void __user *argp = (void __user *)arg; |
1008 | |
1009 | if (!capable(CAP_SYS_RESOURCE)) |
1010 | return -EPERM; |
1011 | |
1012 | switch (cmd) { |
1013 | /* Attach an MTD device command */ |
1014 | case UBI_IOCATT: |
1015 | { |
1016 | struct ubi_attach_req req; |
1017 | struct mtd_info *mtd; |
1018 | |
1019 | dbg_gen("attach MTD device" ); |
1020 | err = copy_from_user(to: &req, from: argp, n: sizeof(struct ubi_attach_req)); |
1021 | if (err) { |
1022 | err = -EFAULT; |
1023 | break; |
1024 | } |
1025 | |
1026 | if (req.mtd_num < 0 || |
1027 | (req.ubi_num < 0 && req.ubi_num != UBI_DEV_NUM_AUTO)) { |
1028 | err = -EINVAL; |
1029 | break; |
1030 | } |
1031 | |
1032 | mtd = get_mtd_device(NULL, num: req.mtd_num); |
1033 | if (IS_ERR(ptr: mtd)) { |
1034 | err = PTR_ERR(ptr: mtd); |
1035 | break; |
1036 | } |
1037 | |
1038 | /* |
1039 | * Note, further request verification is done by |
1040 | * 'ubi_attach_mtd_dev()'. |
1041 | */ |
1042 | mutex_lock(&ubi_devices_mutex); |
1043 | err = ubi_attach_mtd_dev(mtd, ubi_num: req.ubi_num, vid_hdr_offset: req.vid_hdr_offset, |
1044 | max_beb_per1024: req.max_beb_per1024, disable_fm: !!req.disable_fm, |
1045 | need_resv_pool: !!req.need_resv_pool); |
1046 | mutex_unlock(lock: &ubi_devices_mutex); |
1047 | if (err < 0) |
1048 | put_mtd_device(mtd); |
1049 | else |
1050 | /* @err contains UBI device number */ |
1051 | err = put_user(err, (__user int32_t *)argp); |
1052 | |
1053 | break; |
1054 | } |
1055 | |
1056 | /* Detach an MTD device command */ |
1057 | case UBI_IOCDET: |
1058 | { |
1059 | int ubi_num; |
1060 | |
1061 | dbg_gen("detach MTD device" ); |
1062 | err = get_user(ubi_num, (__user int32_t *)argp); |
1063 | if (err) { |
1064 | err = -EFAULT; |
1065 | break; |
1066 | } |
1067 | |
1068 | mutex_lock(&ubi_devices_mutex); |
1069 | err = ubi_detach_mtd_dev(ubi_num, anyway: 0); |
1070 | mutex_unlock(lock: &ubi_devices_mutex); |
1071 | break; |
1072 | } |
1073 | |
1074 | default: |
1075 | err = -ENOTTY; |
1076 | break; |
1077 | } |
1078 | |
1079 | return err; |
1080 | } |
1081 | |
1082 | /* UBI volume character device operations */ |
1083 | const struct file_operations ubi_vol_cdev_operations = { |
1084 | .owner = THIS_MODULE, |
1085 | .open = vol_cdev_open, |
1086 | .release = vol_cdev_release, |
1087 | .llseek = vol_cdev_llseek, |
1088 | .read = vol_cdev_read, |
1089 | .write = vol_cdev_write, |
1090 | .fsync = vol_cdev_fsync, |
1091 | .unlocked_ioctl = vol_cdev_ioctl, |
1092 | .compat_ioctl = compat_ptr_ioctl, |
1093 | }; |
1094 | |
1095 | /* UBI character device operations */ |
1096 | const struct file_operations ubi_cdev_operations = { |
1097 | .owner = THIS_MODULE, |
1098 | .llseek = no_llseek, |
1099 | .unlocked_ioctl = ubi_cdev_ioctl, |
1100 | .compat_ioctl = compat_ptr_ioctl, |
1101 | }; |
1102 | |
1103 | /* UBI control character device operations */ |
1104 | const struct file_operations ubi_ctrl_cdev_operations = { |
1105 | .owner = THIS_MODULE, |
1106 | .unlocked_ioctl = ctrl_cdev_ioctl, |
1107 | .compat_ioctl = compat_ptr_ioctl, |
1108 | .llseek = no_llseek, |
1109 | }; |
1110 | |