1/*
2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2007
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * Author: Artem Bityutskiy (���������������� ����������),
20 *         Frank Haverkamp
21 */
22
23/*
24 * This file includes UBI initialization and building of UBI devices. At the
25 * moment UBI devices may only be added while UBI is initialized, but dynamic
26 * device add/remove functionality is planned. Also, at the moment we only
27 * attach UBI devices by scanning, which will become a bottleneck when flashes
28 * reach certain large size. Then one may improve UBI and add other methods.
29 */
30
31#include <linux/err.h>
32#include <linux/module.h>
33#include <linux/moduleparam.h>
34#include <linux/stringify.h>
35#include <linux/stat.h>
36#include "ubi.h"
37
38/* Maximum length of the 'mtd=' parameter */
39#define MTD_PARAM_LEN_MAX 64
40
41/**
42 * struct mtd_dev_param - MTD device parameter description data structure.
43 * @name: MTD device name or number string
44 * @vid_hdr_offs: VID header offset
45 * @data_offs: data offset
46 */
47struct mtd_dev_param
48{
49	char name[MTD_PARAM_LEN_MAX];
50	int vid_hdr_offs;
51	int data_offs;
52};
53
54/* Numbers of elements set in the @mtd_dev_param array */
55static int mtd_devs = 0;
56
57/* MTD devices specification parameters */
58static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
59
60/* Number of UBI devices in system */
61int ubi_devices_cnt;
62
63/* All UBI devices in system */
64struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
65
66/* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
67struct class *ubi_class;
68
69/* "Show" method for files in '/<sysfs>/class/ubi/' */
70static ssize_t ubi_version_show(struct class *class, char *buf)
71{
72	return sprintf(buf, "%d\n", UBI_VERSION);
73}
74
75/* UBI version attribute ('/<sysfs>/class/ubi/version') */
76static struct class_attribute ubi_version =
77	__ATTR(version, S_IRUGO, ubi_version_show, NULL);
78
79static ssize_t dev_attribute_show(struct device *dev,
80				  struct device_attribute *attr, char *buf);
81
82/* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
83static struct device_attribute dev_eraseblock_size =
84	__ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
85static struct device_attribute dev_avail_eraseblocks =
86	__ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
87static struct device_attribute dev_total_eraseblocks =
88	__ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
89static struct device_attribute dev_volumes_count =
90	__ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
91static struct device_attribute dev_max_ec =
92	__ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
93static struct device_attribute dev_reserved_for_bad =
94	__ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
95static struct device_attribute dev_bad_peb_count =
96	__ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
97static struct device_attribute dev_max_vol_count =
98	__ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
99static struct device_attribute dev_min_io_size =
100	__ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
101static struct device_attribute dev_bgt_enabled =
102	__ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
103
104/* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
105static ssize_t dev_attribute_show(struct device *dev,
106				  struct device_attribute *attr, char *buf)
107{
108	const struct ubi_device *ubi;
109
110	ubi = container_of(dev, struct ubi_device, dev);
111	if (attr == &dev_eraseblock_size)
112		return sprintf(buf, "%d\n", ubi->leb_size);
113	else if (attr == &dev_avail_eraseblocks)
114		return sprintf(buf, "%d\n", ubi->avail_pebs);
115	else if (attr == &dev_total_eraseblocks)
116		return sprintf(buf, "%d\n", ubi->good_peb_count);
117	else if (attr == &dev_volumes_count)
118		return sprintf(buf, "%d\n", ubi->vol_count);
119	else if (attr == &dev_max_ec)
120		return sprintf(buf, "%d\n", ubi->max_ec);
121	else if (attr == &dev_reserved_for_bad)
122		return sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
123	else if (attr == &dev_bad_peb_count)
124		return sprintf(buf, "%d\n", ubi->bad_peb_count);
125	else if (attr == &dev_max_vol_count)
126		return sprintf(buf, "%d\n", ubi->vtbl_slots);
127	else if (attr == &dev_min_io_size)
128		return sprintf(buf, "%d\n", ubi->min_io_size);
129	else if (attr == &dev_bgt_enabled)
130		return sprintf(buf, "%d\n", ubi->thread_enabled);
131	else
132		BUG();
133
134	return 0;
135}
136
137/* Fake "release" method for UBI devices */
138static void dev_release(struct device *dev) { }
139
140/**
141 * ubi_sysfs_init - initialize sysfs for an UBI device.
142 * @ubi: UBI device description object
143 *
144 * This function returns zero in case of success and a negative error code in
145 * case of failure.
146 */
147static int ubi_sysfs_init(struct ubi_device *ubi)
148{
149	int err;
150
151	ubi->dev.release = dev_release;
152	ubi->dev.devt = MKDEV(ubi->major, 0);
153	ubi->dev.class = ubi_class;
154	sprintf(&ubi->dev.bus_id[0], UBI_NAME_STR"%d", ubi->ubi_num);
155	err = device_register(&ubi->dev);
156	if (err)
157		goto out;
158
159	err = device_create_file(&ubi->dev, &dev_eraseblock_size);
160	if (err)
161		goto out_unregister;
162	err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
163	if (err)
164		goto out_eraseblock_size;
165	err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
166	if (err)
167		goto out_avail_eraseblocks;
168	err = device_create_file(&ubi->dev, &dev_volumes_count);
169	if (err)
170		goto out_total_eraseblocks;
171	err = device_create_file(&ubi->dev, &dev_max_ec);
172	if (err)
173		goto out_volumes_count;
174	err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
175	if (err)
176		goto out_volumes_max_ec;
177	err = device_create_file(&ubi->dev, &dev_bad_peb_count);
178	if (err)
179		goto out_reserved_for_bad;
180	err = device_create_file(&ubi->dev, &dev_max_vol_count);
181	if (err)
182		goto out_bad_peb_count;
183	err = device_create_file(&ubi->dev, &dev_min_io_size);
184	if (err)
185		goto out_max_vol_count;
186	err = device_create_file(&ubi->dev, &dev_bgt_enabled);
187	if (err)
188		goto out_min_io_size;
189
190	return 0;
191
192out_min_io_size:
193	device_remove_file(&ubi->dev, &dev_min_io_size);
194out_max_vol_count:
195	device_remove_file(&ubi->dev, &dev_max_vol_count);
196out_bad_peb_count:
197	device_remove_file(&ubi->dev, &dev_bad_peb_count);
198out_reserved_for_bad:
199	device_remove_file(&ubi->dev, &dev_reserved_for_bad);
200out_volumes_max_ec:
201	device_remove_file(&ubi->dev, &dev_max_ec);
202out_volumes_count:
203	device_remove_file(&ubi->dev, &dev_volumes_count);
204out_total_eraseblocks:
205	device_remove_file(&ubi->dev, &dev_total_eraseblocks);
206out_avail_eraseblocks:
207	device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
208out_eraseblock_size:
209	device_remove_file(&ubi->dev, &dev_eraseblock_size);
210out_unregister:
211	device_unregister(&ubi->dev);
212out:
213	ubi_err("failed to initialize sysfs for %s", ubi->ubi_name);
214	return err;
215}
216
217/**
218 * ubi_sysfs_close - close sysfs for an UBI device.
219 * @ubi: UBI device description object
220 */
221static void ubi_sysfs_close(struct ubi_device *ubi)
222{
223	device_remove_file(&ubi->dev, &dev_bgt_enabled);
224	device_remove_file(&ubi->dev, &dev_min_io_size);
225	device_remove_file(&ubi->dev, &dev_max_vol_count);
226	device_remove_file(&ubi->dev, &dev_bad_peb_count);
227	device_remove_file(&ubi->dev, &dev_reserved_for_bad);
228	device_remove_file(&ubi->dev, &dev_max_ec);
229	device_remove_file(&ubi->dev, &dev_volumes_count);
230	device_remove_file(&ubi->dev, &dev_total_eraseblocks);
231	device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
232	device_remove_file(&ubi->dev, &dev_eraseblock_size);
233	device_unregister(&ubi->dev);
234}
235
236/**
237 * kill_volumes - destroy all volumes.
238 * @ubi: UBI device description object
239 */
240static void kill_volumes(struct ubi_device *ubi)
241{
242	int i;
243
244	for (i = 0; i < ubi->vtbl_slots; i++)
245		if (ubi->volumes[i])
246			ubi_free_volume(ubi, i);
247}
248
249/**
250 * uif_init - initialize user interfaces for an UBI device.
251 * @ubi: UBI device description object
252 *
253 * This function returns zero in case of success and a negative error code in
254 * case of failure.
255 */
256static int uif_init(struct ubi_device *ubi)
257{
258	int i, err;
259	dev_t dev;
260
261	mutex_init(&ubi->vtbl_mutex);
262	spin_lock_init(&ubi->volumes_lock);
263
264	sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
265
266	/*
267	 * Major numbers for the UBI character devices are allocated
268	 * dynamically. Major numbers of volume character devices are
269	 * equivalent to ones of the corresponding UBI character device. Minor
270	 * numbers of UBI character devices are 0, while minor numbers of
271	 * volume character devices start from 1. Thus, we allocate one major
272	 * number and ubi->vtbl_slots + 1 minor numbers.
273	 */
274	err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
275	if (err) {
276		ubi_err("cannot register UBI character devices");
277		return err;
278	}
279
280	cdev_init(&ubi->cdev, &ubi_cdev_operations);
281	ubi->major = MAJOR(dev);
282	dbg_msg("%s major is %u", ubi->ubi_name, ubi->major);
283	ubi->cdev.owner = THIS_MODULE;
284
285	dev = MKDEV(ubi->major, 0);
286	err = cdev_add(&ubi->cdev, dev, 1);
287	if (err) {
288		ubi_err("cannot add character device %s", ubi->ubi_name);
289		goto out_unreg;
290	}
291
292	err = ubi_sysfs_init(ubi);
293	if (err)
294		goto out_cdev;
295
296	for (i = 0; i < ubi->vtbl_slots; i++)
297		if (ubi->volumes[i]) {
298			err = ubi_add_volume(ubi, i);
299			if (err)
300				goto out_volumes;
301		}
302
303	return 0;
304
305out_volumes:
306	kill_volumes(ubi);
307	ubi_sysfs_close(ubi);
308out_cdev:
309	cdev_del(&ubi->cdev);
310out_unreg:
311	unregister_chrdev_region(MKDEV(ubi->major, 0),
312				 ubi->vtbl_slots + 1);
313	return err;
314}
315
316/**
317 * uif_close - close user interfaces for an UBI device.
318 * @ubi: UBI device description object
319 */
320static void uif_close(struct ubi_device *ubi)
321{
322	kill_volumes(ubi);
323	ubi_sysfs_close(ubi);
324	cdev_del(&ubi->cdev);
325	unregister_chrdev_region(MKDEV(ubi->major, 0), ubi->vtbl_slots + 1);
326}
327
328/**
329 * attach_by_scanning - attach an MTD device using scanning method.
330 * @ubi: UBI device descriptor
331 *
332 * This function returns zero in case of success and a negative error code in
333 * case of failure.
334 *
335 * Note, currently this is the only method to attach UBI devices. Hopefully in
336 * the future we'll have more scalable attaching methods and avoid full media
337 * scanning. But even in this case scanning will be needed as a fall-back
338 * attaching method if there are some on-flash table corruptions.
339 */
340static int attach_by_scanning(struct ubi_device *ubi)
341{
342	int err;
343	struct ubi_scan_info *si;
344
345	si = ubi_scan(ubi);
346	if (IS_ERR(si))
347		return PTR_ERR(si);
348
349	ubi->bad_peb_count = si->bad_peb_count;
350	ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count;
351	ubi->max_ec = si->max_ec;
352	ubi->mean_ec = si->mean_ec;
353
354	err = ubi_read_volume_table(ubi, si);
355	if (err)
356		goto out_si;
357
358	err = ubi_wl_init_scan(ubi, si);
359	if (err)
360		goto out_vtbl;
361
362	err = ubi_eba_init_scan(ubi, si);
363	if (err)
364		goto out_wl;
365
366	ubi_scan_destroy_si(si);
367	return 0;
368
369out_wl:
370	ubi_wl_close(ubi);
371out_vtbl:
372	kfree(ubi->vtbl);
373out_si:
374	ubi_scan_destroy_si(si);
375	return err;
376}
377
378/**
379 * io_init - initialize I/O unit for a given UBI device.
380 * @ubi: UBI device description object
381 *
382 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
383 * assumed:
384 *   o EC header is always at offset zero - this cannot be changed;
385 *   o VID header starts just after the EC header at the closest address
386 *   aligned to @io->@hdrs_min_io_size;
387 *   o data starts just after the VID header at the closest address aligned to
388 *     @io->@min_io_size
389 *
390 * This function returns zero in case of success and a negative error code in
391 * case of failure.
392 */
393static int io_init(struct ubi_device *ubi)
394{
395	if (ubi->mtd->numeraseregions != 0) {
396		/*
397		 * Some flashes have several erase regions. Different regions
398		 * may have different eraseblock size and other
399		 * characteristics. It looks like mostly multi-region flashes
400		 * have one "main" region and one or more small regions to
401		 * store boot loader code or boot parameters or whatever. I
402		 * guess we should just pick the largest region. But this is
403		 * not implemented.
404		 */
405		ubi_err("multiple regions, not implemented");
406		return -EINVAL;
407	}
408
409	/*
410	 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
411	 * physical eraseblocks maximum.
412	 */
413
414	ubi->peb_size   = ubi->mtd->erasesize;
415	ubi->peb_count  = ubi->mtd->size / ubi->mtd->erasesize;
416	ubi->flash_size = ubi->mtd->size;
417
418	if (ubi->mtd->block_isbad && ubi->mtd->block_markbad)
419		ubi->bad_allowed = 1;
420
421	ubi->min_io_size = ubi->mtd->writesize;
422	ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
423
424	/* Make sure minimal I/O unit is power of 2 */
425	if (ubi->min_io_size == 0 ||
426	    (ubi->min_io_size & (ubi->min_io_size - 1))) {
427		ubi_err("bad min. I/O unit");
428		return -EINVAL;
429	}
430
431	ubi_assert(ubi->hdrs_min_io_size > 0);
432	ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
433	ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
434
435	/* Calculate default aligned sizes of EC and VID headers */
436	ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
437	ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
438
439	dbg_msg("min_io_size      %d", ubi->min_io_size);
440	dbg_msg("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
441	dbg_msg("ec_hdr_alsize    %d", ubi->ec_hdr_alsize);
442	dbg_msg("vid_hdr_alsize   %d", ubi->vid_hdr_alsize);
443
444	if (ubi->vid_hdr_offset == 0)
445		/* Default offset */
446		ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
447				      ubi->ec_hdr_alsize;
448	else {
449		ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
450						~(ubi->hdrs_min_io_size - 1);
451		ubi->vid_hdr_shift = ubi->vid_hdr_offset -
452						ubi->vid_hdr_aloffset;
453	}
454
455	/* Similar for the data offset */
456	if (ubi->leb_start == 0) {
457		ubi->leb_start = ubi->vid_hdr_offset + ubi->vid_hdr_alsize;
458		ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
459	}
460
461	dbg_msg("vid_hdr_offset   %d", ubi->vid_hdr_offset);
462	dbg_msg("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
463	dbg_msg("vid_hdr_shift    %d", ubi->vid_hdr_shift);
464	dbg_msg("leb_start        %d", ubi->leb_start);
465
466	/* The shift must be aligned to 32-bit boundary */
467	if (ubi->vid_hdr_shift % 4) {
468		ubi_err("unaligned VID header shift %d",
469			ubi->vid_hdr_shift);
470		return -EINVAL;
471	}
472
473	/* Check sanity */
474	if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
475	    ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
476	    ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
477	    ubi->leb_start % ubi->min_io_size) {
478		ubi_err("bad VID header (%d) or data offsets (%d)",
479			ubi->vid_hdr_offset, ubi->leb_start);
480		return -EINVAL;
481	}
482
483	/*
484	 * It may happen that EC and VID headers are situated in one minimal
485	 * I/O unit. In this case we can only accept this UBI image in
486	 * read-only mode.
487	 */
488	if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
489		ubi_warn("EC and VID headers are in the same minimal I/O unit, "
490			 "switch to read-only mode");
491		ubi->ro_mode = 1;
492	}
493
494	ubi->leb_size = ubi->peb_size - ubi->leb_start;
495
496	if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
497		ubi_msg("MTD device %d is write-protected, attach in "
498			"read-only mode", ubi->mtd->index);
499		ubi->ro_mode = 1;
500	}
501
502	dbg_msg("leb_size         %d", ubi->leb_size);
503	dbg_msg("ro_mode          %d", ubi->ro_mode);
504
505	/*
506	 * Note, ideally, we have to initialize ubi->bad_peb_count here. But
507	 * unfortunately, MTD does not provide this information. We should loop
508	 * over all physical eraseblocks and invoke mtd->block_is_bad() for
509	 * each physical eraseblock. So, we skip ubi->bad_peb_count
510	 * uninitialized and initialize it after scanning.
511	 */
512
513	return 0;
514}
515
516/**
517 * attach_mtd_dev - attach an MTD device.
518 * @mtd_dev: MTD device name or number string
519 * @vid_hdr_offset: VID header offset
520 * @data_offset: data offset
521 *
522 * This function attaches an MTD device to UBI. It first treats @mtd_dev as the
523 * MTD device name, and tries to open it by this name. If it is unable to open,
524 * it tries to convert @mtd_dev to an integer and open the MTD device by its
525 * number. Returns zero in case of success and a negative error code in case of
526 * failure.
527 */
528static int attach_mtd_dev(const char *mtd_dev, int vid_hdr_offset,
529			  int data_offset)
530{
531	struct ubi_device *ubi;
532	struct mtd_info *mtd;
533	int i, err;
534
535	mtd = get_mtd_device_nm(mtd_dev);
536	if (IS_ERR(mtd)) {
537		int mtd_num;
538		char *endp;
539
540		if (PTR_ERR(mtd) != -ENODEV)
541			return PTR_ERR(mtd);
542
543		/*
544		 * Probably this is not MTD device name but MTD device number -
545		 * check this out.
546		 */
547		mtd_num = simple_strtoul(mtd_dev, &endp, 0);
548		if (*endp != '\0' || mtd_dev == endp) {
549			ubi_err("incorrect MTD device: \"%s\"", mtd_dev);
550			return -ENODEV;
551		}
552
553		mtd = get_mtd_device(NULL, mtd_num);
554		if (IS_ERR(mtd))
555			return PTR_ERR(mtd);
556	}
557
558	/* Check if we already have the same MTD device attached */
559	for (i = 0; i < ubi_devices_cnt; i++)
560		if (ubi_devices[i]->mtd->index == mtd->index) {
561			ubi_err("mtd%d is already attached to ubi%d",
562				mtd->index, i);
563			err = -EINVAL;
564			goto out_mtd;
565		}
566
567	ubi = ubi_devices[ubi_devices_cnt] = kzalloc(sizeof(struct ubi_device),
568						      GFP_KERNEL);
569	if (!ubi) {
570		err = -ENOMEM;
571		goto out_mtd;
572	}
573
574	ubi->ubi_num = ubi_devices_cnt;
575	ubi->mtd = mtd;
576
577	dbg_msg("attaching mtd%d to ubi%d: VID header offset %d data offset %d",
578		ubi->mtd->index, ubi_devices_cnt, vid_hdr_offset, data_offset);
579
580	ubi->vid_hdr_offset = vid_hdr_offset;
581	ubi->leb_start = data_offset;
582	err = io_init(ubi);
583	if (err)
584		goto out_free;
585
586	err = attach_by_scanning(ubi);
587	if (err) {
588		dbg_err("failed to attach by scanning, error %d", err);
589		goto out_free;
590	}
591
592	err = uif_init(ubi);
593	if (err)
594		goto out_detach;
595
596	ubi_devices_cnt += 1;
597
598	ubi_msg("attached mtd%d to ubi%d", ubi->mtd->index, ubi_devices_cnt);
599	ubi_msg("MTD device name:            \"%s\"", ubi->mtd->name);
600	ubi_msg("MTD device size:            %llu MiB", ubi->flash_size >> 20);
601	ubi_msg("physical eraseblock size:   %d bytes (%d KiB)",
602		ubi->peb_size, ubi->peb_size >> 10);
603	ubi_msg("logical eraseblock size:    %d bytes", ubi->leb_size);
604	ubi_msg("number of good PEBs:        %d", ubi->good_peb_count);
605	ubi_msg("number of bad PEBs:         %d", ubi->bad_peb_count);
606	ubi_msg("smallest flash I/O unit:    %d", ubi->min_io_size);
607	ubi_msg("VID header offset:          %d (aligned %d)",
608		ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
609	ubi_msg("data offset:                %d", ubi->leb_start);
610	ubi_msg("max. allowed volumes:       %d", ubi->vtbl_slots);
611	ubi_msg("wear-leveling threshold:    %d", CONFIG_MTD_UBI_WL_THRESHOLD);
612	ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT);
613	ubi_msg("number of user volumes:     %d",
614		ubi->vol_count - UBI_INT_VOL_COUNT);
615	ubi_msg("available PEBs:             %d", ubi->avail_pebs);
616	ubi_msg("total number of reserved PEBs: %d", ubi->rsvd_pebs);
617	ubi_msg("number of PEBs reserved for bad PEB handling: %d",
618		ubi->beb_rsvd_pebs);
619	ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec);
620
621	/* Enable the background thread */
622	if (!DBG_DISABLE_BGT) {
623		ubi->thread_enabled = 1;
624		wake_up_process(ubi->bgt_thread);
625	}
626
627	return 0;
628
629out_detach:
630	ubi_eba_close(ubi);
631	ubi_wl_close(ubi);
632	kfree(ubi->vtbl);
633out_free:
634	kfree(ubi);
635out_mtd:
636	put_mtd_device(mtd);
637	ubi_devices[ubi_devices_cnt] = NULL;
638	return err;
639}
640
641/**
642 * detach_mtd_dev - detach an MTD device.
643 * @ubi: UBI device description object
644 */
645static void detach_mtd_dev(struct ubi_device *ubi)
646{
647	int ubi_num = ubi->ubi_num, mtd_num = ubi->mtd->index;
648
649	dbg_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
650	uif_close(ubi);
651	ubi_eba_close(ubi);
652	ubi_wl_close(ubi);
653	kfree(ubi->vtbl);
654	put_mtd_device(ubi->mtd);
655	kfree(ubi_devices[ubi_num]);
656	ubi_devices[ubi_num] = NULL;
657	ubi_devices_cnt -= 1;
658	ubi_assert(ubi_devices_cnt >= 0);
659	ubi_msg("mtd%d is detached from ubi%d", mtd_num, ubi_num);
660}
661
662static int __init ubi_init(void)
663{
664	int err, i, k;
665
666	/* Ensure that EC and VID headers have correct size */
667	BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
668	BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
669
670	if (mtd_devs > UBI_MAX_DEVICES) {
671		printk("UBI error: too many MTD devices, maximum is %d\n",
672		       UBI_MAX_DEVICES);
673		return -EINVAL;
674	}
675
676	ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
677	if (IS_ERR(ubi_class))
678		return PTR_ERR(ubi_class);
679
680	err = class_create_file(ubi_class, &ubi_version);
681	if (err)
682		goto out_class;
683
684	/* Attach MTD devices */
685	for (i = 0; i < mtd_devs; i++) {
686		struct mtd_dev_param *p = &mtd_dev_param[i];
687
688		cond_resched();
689
690		if (!p->name) {
691			dbg_err("empty name");
692			err = -EINVAL;
693			goto out_detach;
694		}
695
696		err = attach_mtd_dev(p->name, p->vid_hdr_offs, p->data_offs);
697		if (err)
698			goto out_detach;
699	}
700
701	return 0;
702
703out_detach:
704	for (k = 0; k < i; k++)
705		detach_mtd_dev(ubi_devices[k]);
706	class_remove_file(ubi_class, &ubi_version);
707out_class:
708	class_destroy(ubi_class);
709	return err;
710}
711module_init(ubi_init);
712
713static void __exit ubi_exit(void)
714{
715	int i, n = ubi_devices_cnt;
716
717	for (i = 0; i < n; i++)
718		detach_mtd_dev(ubi_devices[i]);
719	class_remove_file(ubi_class, &ubi_version);
720	class_destroy(ubi_class);
721}
722module_exit(ubi_exit);
723
724/**
725 * bytes_str_to_int - convert a string representing number of bytes to an
726 * integer.
727 * @str: the string to convert
728 *
729 * This function returns positive resulting integer in case of success and a
730 * negative error code in case of failure.
731 */
732static int __init bytes_str_to_int(const char *str)
733{
734	char *endp;
735	unsigned long result;
736
737	result = simple_strtoul(str, &endp, 0);
738	if (str == endp || result < 0) {
739		printk("UBI error: incorrect bytes count: \"%s\"\n", str);
740		return -EINVAL;
741	}
742
743	switch (*endp) {
744	case 'G':
745		result *= 1024;
746	case 'M':
747		result *= 1024;
748	case 'K':
749	case 'k':
750		result *= 1024;
751		if (endp[1] == 'i' && (endp[2] == '\0' ||
752			  endp[2] == 'B'  || endp[2] == 'b'))
753			endp += 2;
754	case '\0':
755		break;
756	default:
757		printk("UBI error: incorrect bytes count: \"%s\"\n", str);
758		return -EINVAL;
759	}
760
761	return result;
762}
763
764/**
765 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
766 * @val: the parameter value to parse
767 * @kp: not used
768 *
769 * This function returns zero in case of success and a negative error code in
770 * case of error.
771 */
772static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
773{
774	int i, len;
775	struct mtd_dev_param *p;
776	char buf[MTD_PARAM_LEN_MAX];
777	char *pbuf = &buf[0];
778	char *tokens[3] = {NULL, NULL, NULL};
779
780	if (mtd_devs == UBI_MAX_DEVICES) {
781		printk("UBI error: too many parameters, max. is %d\n",
782		       UBI_MAX_DEVICES);
783		return -EINVAL;
784	}
785
786	len = strnlen(val, MTD_PARAM_LEN_MAX);
787	if (len == MTD_PARAM_LEN_MAX) {
788		printk("UBI error: parameter \"%s\" is too long, max. is %d\n",
789		       val, MTD_PARAM_LEN_MAX);
790		return -EINVAL;
791	}
792
793	if (len == 0) {
794		printk("UBI warning: empty 'mtd=' parameter - ignored\n");
795		return 0;
796	}
797
798	strcpy(buf, val);
799
800	/* Get rid of the final newline */
801	if (buf[len - 1] == '\n')
802		buf[len - 1] = 0;
803
804	for (i = 0; i < 3; i++)
805		tokens[i] = strsep(&pbuf, ",");
806
807	if (pbuf) {
808		printk("UBI error: too many arguments at \"%s\"\n", val);
809		return -EINVAL;
810	}
811
812	if (tokens[0] == '\0')
813		return -EINVAL;
814
815	p = &mtd_dev_param[mtd_devs];
816	strcpy(&p->name[0], tokens[0]);
817
818	if (tokens[1])
819		p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
820	if (tokens[2])
821		p->data_offs = bytes_str_to_int(tokens[2]);
822
823	if (p->vid_hdr_offs < 0)
824		return p->vid_hdr_offs;
825	if (p->data_offs < 0)
826		return p->data_offs;
827
828	mtd_devs += 1;
829	return 0;
830}
831
832module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
833MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: "
834		      "mtd=<name|num>[,<vid_hdr_offs>,<data_offs>]. "
835		      "Multiple \"mtd\" parameters may be specified.\n"
836		      "MTD devices may be specified by their number or name. "
837		      "Optional \"vid_hdr_offs\" and \"data_offs\" parameters "
838		      "specify UBI VID header position and data starting "
839		      "position to be used by UBI.\n"
840		      "Example: mtd=content,1984,2048 mtd=4 - attach MTD device"
841		      "with name content using VID header offset 1984 and data "
842		      "start 2048, and MTD device number 4 using default "
843		      "offsets");
844
845MODULE_VERSION(__stringify(UBI_VERSION));
846MODULE_DESCRIPTION("UBI - Unsorted Block Images");
847MODULE_AUTHOR("Artem Bityutskiy");
848MODULE_LICENSE("GPL");
849