2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2007
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.
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.
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
19 * Author: Artem Bityutskiy (Битюцкий Артём),
24 * This file includes UBI initialization and building of UBI devices.
26 * When UBI is initialized, it attaches all the MTD devices specified as the
27 * module load parameters or the kernel boot parameters. If MTD devices were
28 * specified, UBI does not attach any MTD device, but it is possible to do
29 * later using the "UBI control device".
31 * At the moment we only attach UBI devices by scanning, which will become a
32 * bottleneck when flashes reach certain large size. Then one may improve UBI
33 * and add other methods, although it does not seem to be easy to do.
36 #include <linux/err.h>
37 #include <linux/module.h>
38 #include <linux/moduleparam.h>
39 #include <linux/stringify.h>
40 #include <linux/namei.h>
41 #include <linux/stat.h>
42 #include <linux/miscdevice.h>
43 #include <linux/log2.h>
44 #include <linux/kthread.h>
45 #include <linux/reboot.h>
46 #include <linux/kernel.h>
49 /* Maximum length of the 'mtd=' parameter */
50 #define MTD_PARAM_LEN_MAX 64
53 * struct mtd_dev_param - MTD device parameter description data structure.
54 * @name: MTD character device node path, MTD device name, or MTD device number
56 * @vid_hdr_offs: VID header offset
58 struct mtd_dev_param
{
59 char name
[MTD_PARAM_LEN_MAX
];
63 /* Numbers of elements set in the @mtd_dev_param array */
64 static int __initdata mtd_devs
;
66 /* MTD devices specification parameters */
67 static struct mtd_dev_param __initdata mtd_dev_param
[UBI_MAX_DEVICES
];
69 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
70 struct class *ubi_class
;
72 /* Slab cache for wear-leveling entries */
73 struct kmem_cache
*ubi_wl_entry_slab
;
75 /* UBI control character device */
76 static struct miscdevice ubi_ctrl_cdev
= {
77 .minor
= MISC_DYNAMIC_MINOR
,
79 .fops
= &ubi_ctrl_cdev_operations
,
82 /* All UBI devices in system */
83 static struct ubi_device
*ubi_devices
[UBI_MAX_DEVICES
];
85 /* Serializes UBI devices creations and removals */
86 DEFINE_MUTEX(ubi_devices_mutex
);
88 /* Protects @ubi_devices and @ubi->ref_count */
89 static DEFINE_SPINLOCK(ubi_devices_lock
);
91 /* "Show" method for files in '/<sysfs>/class/ubi/' */
92 static ssize_t
ubi_version_show(struct class *class, struct class_attribute
*attr
,
95 return sprintf(buf
, "%d\n", UBI_VERSION
);
98 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
99 static struct class_attribute ubi_version
=
100 __ATTR(version
, S_IRUGO
, ubi_version_show
, NULL
);
102 static ssize_t
dev_attribute_show(struct device
*dev
,
103 struct device_attribute
*attr
, char *buf
);
105 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
106 static struct device_attribute dev_eraseblock_size
=
107 __ATTR(eraseblock_size
, S_IRUGO
, dev_attribute_show
, NULL
);
108 static struct device_attribute dev_avail_eraseblocks
=
109 __ATTR(avail_eraseblocks
, S_IRUGO
, dev_attribute_show
, NULL
);
110 static struct device_attribute dev_total_eraseblocks
=
111 __ATTR(total_eraseblocks
, S_IRUGO
, dev_attribute_show
, NULL
);
112 static struct device_attribute dev_volumes_count
=
113 __ATTR(volumes_count
, S_IRUGO
, dev_attribute_show
, NULL
);
114 static struct device_attribute dev_max_ec
=
115 __ATTR(max_ec
, S_IRUGO
, dev_attribute_show
, NULL
);
116 static struct device_attribute dev_reserved_for_bad
=
117 __ATTR(reserved_for_bad
, S_IRUGO
, dev_attribute_show
, NULL
);
118 static struct device_attribute dev_bad_peb_count
=
119 __ATTR(bad_peb_count
, S_IRUGO
, dev_attribute_show
, NULL
);
120 static struct device_attribute dev_max_vol_count
=
121 __ATTR(max_vol_count
, S_IRUGO
, dev_attribute_show
, NULL
);
122 static struct device_attribute dev_min_io_size
=
123 __ATTR(min_io_size
, S_IRUGO
, dev_attribute_show
, NULL
);
124 static struct device_attribute dev_bgt_enabled
=
125 __ATTR(bgt_enabled
, S_IRUGO
, dev_attribute_show
, NULL
);
126 static struct device_attribute dev_mtd_num
=
127 __ATTR(mtd_num
, S_IRUGO
, dev_attribute_show
, NULL
);
130 * ubi_volume_notify - send a volume change notification.
131 * @ubi: UBI device description object
132 * @vol: volume description object of the changed volume
133 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
135 * This is a helper function which notifies all subscribers about a volume
136 * change event (creation, removal, re-sizing, re-naming, updating). Returns
137 * zero in case of success and a negative error code in case of failure.
139 int ubi_volume_notify(struct ubi_device
*ubi
, struct ubi_volume
*vol
, int ntype
)
141 struct ubi_notification nt
;
143 ubi_do_get_device_info(ubi
, &nt
.di
);
144 ubi_do_get_volume_info(ubi
, vol
, &nt
.vi
);
145 return blocking_notifier_call_chain(&ubi_notifiers
, ntype
, &nt
);
149 * ubi_notify_all - send a notification to all volumes.
150 * @ubi: UBI device description object
151 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
152 * @nb: the notifier to call
154 * This function walks all volumes of UBI device @ubi and sends the @ntype
155 * notification for each volume. If @nb is %NULL, then all registered notifiers
156 * are called, otherwise only the @nb notifier is called. Returns the number of
157 * sent notifications.
159 int ubi_notify_all(struct ubi_device
*ubi
, int ntype
, struct notifier_block
*nb
)
161 struct ubi_notification nt
;
164 ubi_do_get_device_info(ubi
, &nt
.di
);
166 mutex_lock(&ubi
->device_mutex
);
167 for (i
= 0; i
< ubi
->vtbl_slots
; i
++) {
169 * Since the @ubi->device is locked, and we are not going to
170 * change @ubi->volumes, we do not have to lock
171 * @ubi->volumes_lock.
173 if (!ubi
->volumes
[i
])
176 ubi_do_get_volume_info(ubi
, ubi
->volumes
[i
], &nt
.vi
);
178 nb
->notifier_call(nb
, ntype
, &nt
);
180 blocking_notifier_call_chain(&ubi_notifiers
, ntype
,
184 mutex_unlock(&ubi
->device_mutex
);
190 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
191 * @nb: the notifier to call
193 * This function walks all UBI devices and volumes and sends the
194 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
195 * registered notifiers are called, otherwise only the @nb notifier is called.
196 * Returns the number of sent notifications.
198 int ubi_enumerate_volumes(struct notifier_block
*nb
)
203 * Since the @ubi_devices_mutex is locked, and we are not going to
204 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
206 for (i
= 0; i
< UBI_MAX_DEVICES
; i
++) {
207 struct ubi_device
*ubi
= ubi_devices
[i
];
211 count
+= ubi_notify_all(ubi
, UBI_VOLUME_ADDED
, nb
);
218 * ubi_get_device - get UBI device.
219 * @ubi_num: UBI device number
221 * This function returns UBI device description object for UBI device number
222 * @ubi_num, or %NULL if the device does not exist. This function increases the
223 * device reference count to prevent removal of the device. In other words, the
224 * device cannot be removed if its reference count is not zero.
226 struct ubi_device
*ubi_get_device(int ubi_num
)
228 struct ubi_device
*ubi
;
230 spin_lock(&ubi_devices_lock
);
231 ubi
= ubi_devices
[ubi_num
];
233 ubi_assert(ubi
->ref_count
>= 0);
235 get_device(&ubi
->dev
);
237 spin_unlock(&ubi_devices_lock
);
243 * ubi_put_device - drop an UBI device reference.
244 * @ubi: UBI device description object
246 void ubi_put_device(struct ubi_device
*ubi
)
248 spin_lock(&ubi_devices_lock
);
250 put_device(&ubi
->dev
);
251 spin_unlock(&ubi_devices_lock
);
255 * ubi_get_by_major - get UBI device by character device major number.
256 * @major: major number
258 * This function is similar to 'ubi_get_device()', but it searches the device
259 * by its major number.
261 struct ubi_device
*ubi_get_by_major(int major
)
264 struct ubi_device
*ubi
;
266 spin_lock(&ubi_devices_lock
);
267 for (i
= 0; i
< UBI_MAX_DEVICES
; i
++) {
268 ubi
= ubi_devices
[i
];
269 if (ubi
&& MAJOR(ubi
->cdev
.dev
) == major
) {
270 ubi_assert(ubi
->ref_count
>= 0);
272 get_device(&ubi
->dev
);
273 spin_unlock(&ubi_devices_lock
);
277 spin_unlock(&ubi_devices_lock
);
283 * ubi_major2num - get UBI device number by character device major number.
284 * @major: major number
286 * This function searches UBI device number object by its major number. If UBI
287 * device was not found, this function returns -ENODEV, otherwise the UBI device
288 * number is returned.
290 int ubi_major2num(int major
)
292 int i
, ubi_num
= -ENODEV
;
294 spin_lock(&ubi_devices_lock
);
295 for (i
= 0; i
< UBI_MAX_DEVICES
; i
++) {
296 struct ubi_device
*ubi
= ubi_devices
[i
];
298 if (ubi
&& MAJOR(ubi
->cdev
.dev
) == major
) {
299 ubi_num
= ubi
->ubi_num
;
303 spin_unlock(&ubi_devices_lock
);
308 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
309 static ssize_t
dev_attribute_show(struct device
*dev
,
310 struct device_attribute
*attr
, char *buf
)
313 struct ubi_device
*ubi
;
316 * The below code looks weird, but it actually makes sense. We get the
317 * UBI device reference from the contained 'struct ubi_device'. But it
318 * is unclear if the device was removed or not yet. Indeed, if the
319 * device was removed before we increased its reference count,
320 * 'ubi_get_device()' will return -ENODEV and we fail.
322 * Remember, 'struct ubi_device' is freed in the release function, so
323 * we still can use 'ubi->ubi_num'.
325 ubi
= container_of(dev
, struct ubi_device
, dev
);
326 ubi
= ubi_get_device(ubi
->ubi_num
);
330 if (attr
== &dev_eraseblock_size
)
331 ret
= sprintf(buf
, "%d\n", ubi
->leb_size
);
332 else if (attr
== &dev_avail_eraseblocks
)
333 ret
= sprintf(buf
, "%d\n", ubi
->avail_pebs
);
334 else if (attr
== &dev_total_eraseblocks
)
335 ret
= sprintf(buf
, "%d\n", ubi
->good_peb_count
);
336 else if (attr
== &dev_volumes_count
)
337 ret
= sprintf(buf
, "%d\n", ubi
->vol_count
- UBI_INT_VOL_COUNT
);
338 else if (attr
== &dev_max_ec
)
339 ret
= sprintf(buf
, "%d\n", ubi
->max_ec
);
340 else if (attr
== &dev_reserved_for_bad
)
341 ret
= sprintf(buf
, "%d\n", ubi
->beb_rsvd_pebs
);
342 else if (attr
== &dev_bad_peb_count
)
343 ret
= sprintf(buf
, "%d\n", ubi
->bad_peb_count
);
344 else if (attr
== &dev_max_vol_count
)
345 ret
= sprintf(buf
, "%d\n", ubi
->vtbl_slots
);
346 else if (attr
== &dev_min_io_size
)
347 ret
= sprintf(buf
, "%d\n", ubi
->min_io_size
);
348 else if (attr
== &dev_bgt_enabled
)
349 ret
= sprintf(buf
, "%d\n", ubi
->thread_enabled
);
350 else if (attr
== &dev_mtd_num
)
351 ret
= sprintf(buf
, "%d\n", ubi
->mtd
->index
);
359 static void dev_release(struct device
*dev
)
361 struct ubi_device
*ubi
= container_of(dev
, struct ubi_device
, dev
);
367 * ubi_sysfs_init - initialize sysfs for an UBI device.
368 * @ubi: UBI device description object
369 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
372 * This function returns zero in case of success and a negative error code in
375 static int ubi_sysfs_init(struct ubi_device
*ubi
, int *ref
)
379 ubi
->dev
.release
= dev_release
;
380 ubi
->dev
.devt
= ubi
->cdev
.dev
;
381 ubi
->dev
.class = ubi_class
;
382 dev_set_name(&ubi
->dev
, UBI_NAME_STR
"%d", ubi
->ubi_num
);
383 err
= device_register(&ubi
->dev
);
388 err
= device_create_file(&ubi
->dev
, &dev_eraseblock_size
);
391 err
= device_create_file(&ubi
->dev
, &dev_avail_eraseblocks
);
394 err
= device_create_file(&ubi
->dev
, &dev_total_eraseblocks
);
397 err
= device_create_file(&ubi
->dev
, &dev_volumes_count
);
400 err
= device_create_file(&ubi
->dev
, &dev_max_ec
);
403 err
= device_create_file(&ubi
->dev
, &dev_reserved_for_bad
);
406 err
= device_create_file(&ubi
->dev
, &dev_bad_peb_count
);
409 err
= device_create_file(&ubi
->dev
, &dev_max_vol_count
);
412 err
= device_create_file(&ubi
->dev
, &dev_min_io_size
);
415 err
= device_create_file(&ubi
->dev
, &dev_bgt_enabled
);
418 err
= device_create_file(&ubi
->dev
, &dev_mtd_num
);
423 * ubi_sysfs_close - close sysfs for an UBI device.
424 * @ubi: UBI device description object
426 static void ubi_sysfs_close(struct ubi_device
*ubi
)
428 device_remove_file(&ubi
->dev
, &dev_mtd_num
);
429 device_remove_file(&ubi
->dev
, &dev_bgt_enabled
);
430 device_remove_file(&ubi
->dev
, &dev_min_io_size
);
431 device_remove_file(&ubi
->dev
, &dev_max_vol_count
);
432 device_remove_file(&ubi
->dev
, &dev_bad_peb_count
);
433 device_remove_file(&ubi
->dev
, &dev_reserved_for_bad
);
434 device_remove_file(&ubi
->dev
, &dev_max_ec
);
435 device_remove_file(&ubi
->dev
, &dev_volumes_count
);
436 device_remove_file(&ubi
->dev
, &dev_total_eraseblocks
);
437 device_remove_file(&ubi
->dev
, &dev_avail_eraseblocks
);
438 device_remove_file(&ubi
->dev
, &dev_eraseblock_size
);
439 device_unregister(&ubi
->dev
);
443 * kill_volumes - destroy all user volumes.
444 * @ubi: UBI device description object
446 static void kill_volumes(struct ubi_device
*ubi
)
450 for (i
= 0; i
< ubi
->vtbl_slots
; i
++)
452 ubi_free_volume(ubi
, ubi
->volumes
[i
]);
456 * uif_init - initialize user interfaces for an UBI device.
457 * @ubi: UBI device description object
458 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
459 * taken, otherwise set to %0
461 * This function initializes various user interfaces for an UBI device. If the
462 * initialization fails at an early stage, this function frees all the
463 * resources it allocated, returns an error, and @ref is set to %0. However,
464 * if the initialization fails after the UBI device was registered in the
465 * driver core subsystem, this function takes a reference to @ubi->dev, because
466 * otherwise the release function ('dev_release()') would free whole @ubi
467 * object. The @ref argument is set to %1 in this case. The caller has to put
470 * This function returns zero in case of success and a negative error code in
473 static int uif_init(struct ubi_device
*ubi
, int *ref
)
479 sprintf(ubi
->ubi_name
, UBI_NAME_STR
"%d", ubi
->ubi_num
);
482 * Major numbers for the UBI character devices are allocated
483 * dynamically. Major numbers of volume character devices are
484 * equivalent to ones of the corresponding UBI character device. Minor
485 * numbers of UBI character devices are 0, while minor numbers of
486 * volume character devices start from 1. Thus, we allocate one major
487 * number and ubi->vtbl_slots + 1 minor numbers.
489 err
= alloc_chrdev_region(&dev
, 0, ubi
->vtbl_slots
+ 1, ubi
->ubi_name
);
491 ubi_err("cannot register UBI character devices");
495 ubi_assert(MINOR(dev
) == 0);
496 cdev_init(&ubi
->cdev
, &ubi_cdev_operations
);
497 dbg_gen("%s major is %u", ubi
->ubi_name
, MAJOR(dev
));
498 ubi
->cdev
.owner
= THIS_MODULE
;
500 err
= cdev_add(&ubi
->cdev
, dev
, 1);
502 ubi_err("cannot add character device");
506 err
= ubi_sysfs_init(ubi
, ref
);
510 for (i
= 0; i
< ubi
->vtbl_slots
; i
++)
511 if (ubi
->volumes
[i
]) {
512 err
= ubi_add_volume(ubi
, ubi
->volumes
[i
]);
514 ubi_err("cannot add volume %d", i
);
525 get_device(&ubi
->dev
);
526 ubi_sysfs_close(ubi
);
527 cdev_del(&ubi
->cdev
);
529 unregister_chrdev_region(ubi
->cdev
.dev
, ubi
->vtbl_slots
+ 1);
530 ubi_err("cannot initialize UBI %s, error %d", ubi
->ubi_name
, err
);
535 * uif_close - close user interfaces for an UBI device.
536 * @ubi: UBI device description object
538 * Note, since this function un-registers UBI volume device objects (@vol->dev),
539 * the memory allocated voe the volumes is freed as well (in the release
542 static void uif_close(struct ubi_device
*ubi
)
545 ubi_sysfs_close(ubi
);
546 cdev_del(&ubi
->cdev
);
547 unregister_chrdev_region(ubi
->cdev
.dev
, ubi
->vtbl_slots
+ 1);
551 * free_internal_volumes - free internal volumes.
552 * @ubi: UBI device description object
554 static void free_internal_volumes(struct ubi_device
*ubi
)
558 for (i
= ubi
->vtbl_slots
;
559 i
< ubi
->vtbl_slots
+ UBI_INT_VOL_COUNT
; i
++) {
560 kfree(ubi
->volumes
[i
]->eba_tbl
);
561 kfree(ubi
->volumes
[i
]);
566 * attach_by_scanning - attach an MTD device using scanning method.
567 * @ubi: UBI device descriptor
569 * This function returns zero in case of success and a negative error code in
572 * Note, currently this is the only method to attach UBI devices. Hopefully in
573 * the future we'll have more scalable attaching methods and avoid full media
574 * scanning. But even in this case scanning will be needed as a fall-back
575 * attaching method if there are some on-flash table corruptions.
577 static int attach_by_scanning(struct ubi_device
*ubi
)
580 struct ubi_scan_info
*si
;
586 ubi
->bad_peb_count
= si
->bad_peb_count
;
587 ubi
->good_peb_count
= ubi
->peb_count
- ubi
->bad_peb_count
;
588 ubi
->max_ec
= si
->max_ec
;
589 ubi
->mean_ec
= si
->mean_ec
;
591 err
= ubi_read_volume_table(ubi
, si
);
595 err
= ubi_wl_init_scan(ubi
, si
);
599 err
= ubi_eba_init_scan(ubi
, si
);
603 ubi_scan_destroy_si(si
);
609 free_internal_volumes(ubi
);
612 ubi_scan_destroy_si(si
);
617 * io_init - initialize I/O sub-system for a given UBI device.
618 * @ubi: UBI device description object
620 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
622 * o EC header is always at offset zero - this cannot be changed;
623 * o VID header starts just after the EC header at the closest address
624 * aligned to @io->hdrs_min_io_size;
625 * o data starts just after the VID header at the closest address aligned to
628 * This function returns zero in case of success and a negative error code in
631 static int io_init(struct ubi_device
*ubi
)
633 if (ubi
->mtd
->numeraseregions
!= 0) {
635 * Some flashes have several erase regions. Different regions
636 * may have different eraseblock size and other
637 * characteristics. It looks like mostly multi-region flashes
638 * have one "main" region and one or more small regions to
639 * store boot loader code or boot parameters or whatever. I
640 * guess we should just pick the largest region. But this is
643 ubi_err("multiple regions, not implemented");
647 if (ubi
->vid_hdr_offset
< 0)
651 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
652 * physical eraseblocks maximum.
655 ubi
->peb_size
= ubi
->mtd
->erasesize
;
656 ubi
->peb_count
= mtd_div_by_eb(ubi
->mtd
->size
, ubi
->mtd
);
657 ubi
->flash_size
= ubi
->mtd
->size
;
659 if (ubi
->mtd
->block_isbad
&& ubi
->mtd
->block_markbad
)
660 ubi
->bad_allowed
= 1;
662 if (ubi
->mtd
->type
== MTD_NORFLASH
) {
663 ubi_assert(ubi
->mtd
->writesize
== 1);
667 ubi
->min_io_size
= ubi
->mtd
->writesize
;
668 ubi
->hdrs_min_io_size
= ubi
->mtd
->writesize
>> ubi
->mtd
->subpage_sft
;
671 * Make sure minimal I/O unit is power of 2. Note, there is no
672 * fundamental reason for this assumption. It is just an optimization
673 * which allows us to avoid costly division operations.
675 if (!is_power_of_2(ubi
->min_io_size
)) {
676 ubi_err("min. I/O unit (%d) is not power of 2",
681 ubi_assert(ubi
->hdrs_min_io_size
> 0);
682 ubi_assert(ubi
->hdrs_min_io_size
<= ubi
->min_io_size
);
683 ubi_assert(ubi
->min_io_size
% ubi
->hdrs_min_io_size
== 0);
685 /* Calculate default aligned sizes of EC and VID headers */
686 ubi
->ec_hdr_alsize
= ALIGN(UBI_EC_HDR_SIZE
, ubi
->hdrs_min_io_size
);
687 ubi
->vid_hdr_alsize
= ALIGN(UBI_VID_HDR_SIZE
, ubi
->hdrs_min_io_size
);
689 dbg_msg("min_io_size %d", ubi
->min_io_size
);
690 dbg_msg("hdrs_min_io_size %d", ubi
->hdrs_min_io_size
);
691 dbg_msg("ec_hdr_alsize %d", ubi
->ec_hdr_alsize
);
692 dbg_msg("vid_hdr_alsize %d", ubi
->vid_hdr_alsize
);
694 if (ubi
->vid_hdr_offset
== 0)
696 ubi
->vid_hdr_offset
= ubi
->vid_hdr_aloffset
=
699 ubi
->vid_hdr_aloffset
= ubi
->vid_hdr_offset
&
700 ~(ubi
->hdrs_min_io_size
- 1);
701 ubi
->vid_hdr_shift
= ubi
->vid_hdr_offset
-
702 ubi
->vid_hdr_aloffset
;
705 /* Similar for the data offset */
706 ubi
->leb_start
= ubi
->vid_hdr_offset
+ UBI_EC_HDR_SIZE
;
707 ubi
->leb_start
= ALIGN(ubi
->leb_start
, ubi
->min_io_size
);
709 dbg_msg("vid_hdr_offset %d", ubi
->vid_hdr_offset
);
710 dbg_msg("vid_hdr_aloffset %d", ubi
->vid_hdr_aloffset
);
711 dbg_msg("vid_hdr_shift %d", ubi
->vid_hdr_shift
);
712 dbg_msg("leb_start %d", ubi
->leb_start
);
714 /* The shift must be aligned to 32-bit boundary */
715 if (ubi
->vid_hdr_shift
% 4) {
716 ubi_err("unaligned VID header shift %d",
722 if (ubi
->vid_hdr_offset
< UBI_EC_HDR_SIZE
||
723 ubi
->leb_start
< ubi
->vid_hdr_offset
+ UBI_VID_HDR_SIZE
||
724 ubi
->leb_start
> ubi
->peb_size
- UBI_VID_HDR_SIZE
||
725 ubi
->leb_start
& (ubi
->min_io_size
- 1)) {
726 ubi_err("bad VID header (%d) or data offsets (%d)",
727 ubi
->vid_hdr_offset
, ubi
->leb_start
);
732 * Set maximum amount of physical erroneous eraseblocks to be 10%.
733 * Erroneous PEB are those which have read errors.
735 ubi
->max_erroneous
= ubi
->peb_count
/ 10;
736 if (ubi
->max_erroneous
< 16)
737 ubi
->max_erroneous
= 16;
738 dbg_msg("max_erroneous %d", ubi
->max_erroneous
);
741 * It may happen that EC and VID headers are situated in one minimal
742 * I/O unit. In this case we can only accept this UBI image in
745 if (ubi
->vid_hdr_offset
+ UBI_VID_HDR_SIZE
<= ubi
->hdrs_min_io_size
) {
746 ubi_warn("EC and VID headers are in the same minimal I/O unit, "
747 "switch to read-only mode");
751 ubi
->leb_size
= ubi
->peb_size
- ubi
->leb_start
;
753 if (!(ubi
->mtd
->flags
& MTD_WRITEABLE
)) {
754 ubi_msg("MTD device %d is write-protected, attach in "
755 "read-only mode", ubi
->mtd
->index
);
759 ubi_msg("physical eraseblock size: %d bytes (%d KiB)",
760 ubi
->peb_size
, ubi
->peb_size
>> 10);
761 ubi_msg("logical eraseblock size: %d bytes", ubi
->leb_size
);
762 ubi_msg("smallest flash I/O unit: %d", ubi
->min_io_size
);
763 if (ubi
->hdrs_min_io_size
!= ubi
->min_io_size
)
764 ubi_msg("sub-page size: %d",
765 ubi
->hdrs_min_io_size
);
766 ubi_msg("VID header offset: %d (aligned %d)",
767 ubi
->vid_hdr_offset
, ubi
->vid_hdr_aloffset
);
768 ubi_msg("data offset: %d", ubi
->leb_start
);
771 * Note, ideally, we have to initialize ubi->bad_peb_count here. But
772 * unfortunately, MTD does not provide this information. We should loop
773 * over all physical eraseblocks and invoke mtd->block_is_bad() for
774 * each physical eraseblock. So, we skip ubi->bad_peb_count
775 * uninitialized and initialize it after scanning.
782 * autoresize - re-size the volume which has the "auto-resize" flag set.
783 * @ubi: UBI device description object
784 * @vol_id: ID of the volume to re-size
786 * This function re-sizes the volume marked by the @UBI_VTBL_AUTORESIZE_FLG in
787 * the volume table to the largest possible size. See comments in ubi-header.h
788 * for more description of the flag. Returns zero in case of success and a
789 * negative error code in case of failure.
791 static int autoresize(struct ubi_device
*ubi
, int vol_id
)
793 struct ubi_volume_desc desc
;
794 struct ubi_volume
*vol
= ubi
->volumes
[vol_id
];
795 int err
, old_reserved_pebs
= vol
->reserved_pebs
;
798 * Clear the auto-resize flag in the volume in-memory copy of the
799 * volume table, and 'ubi_resize_volume()' will propagate this change
802 ubi
->vtbl
[vol_id
].flags
&= ~UBI_VTBL_AUTORESIZE_FLG
;
804 if (ubi
->avail_pebs
== 0) {
805 struct ubi_vtbl_record vtbl_rec
;
808 * No available PEBs to re-size the volume, clear the flag on
811 memcpy(&vtbl_rec
, &ubi
->vtbl
[vol_id
],
812 sizeof(struct ubi_vtbl_record
));
813 err
= ubi_change_vtbl_record(ubi
, vol_id
, &vtbl_rec
);
815 ubi_err("cannot clean auto-resize flag for volume %d",
819 err
= ubi_resize_volume(&desc
,
820 old_reserved_pebs
+ ubi
->avail_pebs
);
822 ubi_err("cannot auto-resize volume %d", vol_id
);
828 ubi_msg("volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id
,
829 vol
->name
, old_reserved_pebs
, vol
->reserved_pebs
);
834 * ubi_reboot_notifier - halt UBI transactions immediately prior to a reboot.
835 * @n: reboot notifier object
836 * @state: SYS_RESTART, SYS_HALT, or SYS_POWER_OFF
837 * @cmd: pointer to command string for RESTART2
839 * This function stops the UBI background thread so that the flash device
840 * remains quiescent when Linux restarts the system. Any queued work will be
841 * discarded, but this function will block until do_work() finishes if an
842 * operation is already in progress.
844 * This function solves a real-life problem observed on NOR flashes when an
845 * PEB erase operation starts, then the system is rebooted before the erase is
846 * finishes, and the boot loader gets confused and dies. So we prefer to finish
847 * the ongoing operation before rebooting.
849 static int ubi_reboot_notifier(struct notifier_block
*n
, unsigned long state
,
852 struct ubi_device
*ubi
;
854 ubi
= container_of(n
, struct ubi_device
, reboot_notifier
);
856 kthread_stop(ubi
->bgt_thread
);
857 ubi_sync(ubi
->ubi_num
);
862 * ubi_attach_mtd_dev - attach an MTD device.
863 * @mtd: MTD device description object
864 * @ubi_num: number to assign to the new UBI device
865 * @vid_hdr_offset: VID header offset
867 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
868 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
869 * which case this function finds a vacant device number and assigns it
870 * automatically. Returns the new UBI device number in case of success and a
871 * negative error code in case of failure.
873 * Note, the invocations of this function has to be serialized by the
874 * @ubi_devices_mutex.
876 int ubi_attach_mtd_dev(struct mtd_info
*mtd
, int ubi_num
, int vid_hdr_offset
)
878 struct ubi_device
*ubi
;
882 * Check if we already have the same MTD device attached.
884 * Note, this function assumes that UBI devices creations and deletions
885 * are serialized, so it does not take the &ubi_devices_lock.
887 for (i
= 0; i
< UBI_MAX_DEVICES
; i
++) {
888 ubi
= ubi_devices
[i
];
889 if (ubi
&& mtd
->index
== ubi
->mtd
->index
) {
890 dbg_err("mtd%d is already attached to ubi%d",
897 * Make sure this MTD device is not emulated on top of an UBI volume
898 * already. Well, generally this recursion works fine, but there are
899 * different problems like the UBI module takes a reference to itself
900 * by attaching (and thus, opening) the emulated MTD device. This
901 * results in inability to unload the module. And in general it makes
902 * no sense to attach emulated MTD devices, so we prohibit this.
904 if (mtd
->type
== MTD_UBIVOLUME
) {
905 ubi_err("refuse attaching mtd%d - it is already emulated on "
906 "top of UBI", mtd
->index
);
910 if (ubi_num
== UBI_DEV_NUM_AUTO
) {
911 /* Search for an empty slot in the @ubi_devices array */
912 for (ubi_num
= 0; ubi_num
< UBI_MAX_DEVICES
; ubi_num
++)
913 if (!ubi_devices
[ubi_num
])
915 if (ubi_num
== UBI_MAX_DEVICES
) {
916 dbg_err("only %d UBI devices may be created",
921 if (ubi_num
>= UBI_MAX_DEVICES
)
924 /* Make sure ubi_num is not busy */
925 if (ubi_devices
[ubi_num
]) {
926 dbg_err("ubi%d already exists", ubi_num
);
931 ubi
= kzalloc(sizeof(struct ubi_device
), GFP_KERNEL
);
936 ubi
->ubi_num
= ubi_num
;
937 ubi
->vid_hdr_offset
= vid_hdr_offset
;
938 ubi
->autoresize_vol_id
= -1;
940 mutex_init(&ubi
->buf_mutex
);
941 mutex_init(&ubi
->ckvol_mutex
);
942 mutex_init(&ubi
->device_mutex
);
943 spin_lock_init(&ubi
->volumes_lock
);
945 ubi_msg("attaching mtd%d to ubi%d", mtd
->index
, ubi_num
);
952 ubi
->peb_buf1
= vmalloc(ubi
->peb_size
);
956 ubi
->peb_buf2
= vmalloc(ubi
->peb_size
);
960 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
961 mutex_init(&ubi
->dbg_buf_mutex
);
962 ubi
->dbg_peb_buf
= vmalloc(ubi
->peb_size
);
963 if (!ubi
->dbg_peb_buf
)
967 err
= attach_by_scanning(ubi
);
969 dbg_err("failed to attach by scanning, error %d", err
);
973 if (ubi
->autoresize_vol_id
!= -1) {
974 err
= autoresize(ubi
, ubi
->autoresize_vol_id
);
979 err
= uif_init(ubi
, &ref
);
983 ubi
->bgt_thread
= kthread_create(ubi_thread
, ubi
, ubi
->bgt_name
);
984 if (IS_ERR(ubi
->bgt_thread
)) {
985 err
= PTR_ERR(ubi
->bgt_thread
);
986 ubi_err("cannot spawn \"%s\", error %d", ubi
->bgt_name
,
991 ubi_msg("attached mtd%d to ubi%d", mtd
->index
, ubi_num
);
992 ubi_msg("MTD device name: \"%s\"", mtd
->name
);
993 ubi_msg("MTD device size: %llu MiB", ubi
->flash_size
>> 20);
994 ubi_msg("number of good PEBs: %d", ubi
->good_peb_count
);
995 ubi_msg("number of bad PEBs: %d", ubi
->bad_peb_count
);
996 ubi_msg("max. allowed volumes: %d", ubi
->vtbl_slots
);
997 ubi_msg("wear-leveling threshold: %d", CONFIG_MTD_UBI_WL_THRESHOLD
);
998 ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT
);
999 ubi_msg("number of user volumes: %d",
1000 ubi
->vol_count
- UBI_INT_VOL_COUNT
);
1001 ubi_msg("available PEBs: %d", ubi
->avail_pebs
);
1002 ubi_msg("total number of reserved PEBs: %d", ubi
->rsvd_pebs
);
1003 ubi_msg("number of PEBs reserved for bad PEB handling: %d",
1004 ubi
->beb_rsvd_pebs
);
1005 ubi_msg("max/mean erase counter: %d/%d", ubi
->max_ec
, ubi
->mean_ec
);
1006 ubi_msg("image sequence number: %d", ubi
->image_seq
);
1009 * The below lock makes sure we do not race with 'ubi_thread()' which
1010 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1012 spin_lock(&ubi
->wl_lock
);
1013 if (!DBG_DISABLE_BGT
)
1014 ubi
->thread_enabled
= 1;
1015 wake_up_process(ubi
->bgt_thread
);
1016 spin_unlock(&ubi
->wl_lock
);
1018 /* Flash device priority is 0 - UBI needs to shut down first */
1019 ubi
->reboot_notifier
.priority
= 1;
1020 ubi
->reboot_notifier
.notifier_call
= ubi_reboot_notifier
;
1021 register_reboot_notifier(&ubi
->reboot_notifier
);
1023 ubi_devices
[ubi_num
] = ubi
;
1024 ubi_notify_all(ubi
, UBI_VOLUME_ADDED
, NULL
);
1031 free_internal_volumes(ubi
);
1034 vfree(ubi
->peb_buf1
);
1035 vfree(ubi
->peb_buf2
);
1036 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
1037 vfree(ubi
->dbg_peb_buf
);
1040 put_device(&ubi
->dev
);
1047 * ubi_detach_mtd_dev - detach an MTD device.
1048 * @ubi_num: UBI device number to detach from
1049 * @anyway: detach MTD even if device reference count is not zero
1051 * This function destroys an UBI device number @ubi_num and detaches the
1052 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1053 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1056 * Note, the invocations of this function has to be serialized by the
1057 * @ubi_devices_mutex.
1059 int ubi_detach_mtd_dev(int ubi_num
, int anyway
)
1061 struct ubi_device
*ubi
;
1063 if (ubi_num
< 0 || ubi_num
>= UBI_MAX_DEVICES
)
1066 ubi
= ubi_get_device(ubi_num
);
1070 spin_lock(&ubi_devices_lock
);
1071 put_device(&ubi
->dev
);
1072 ubi
->ref_count
-= 1;
1073 if (ubi
->ref_count
) {
1075 spin_unlock(&ubi_devices_lock
);
1078 /* This may only happen if there is a bug */
1079 ubi_err("%s reference count %d, destroy anyway",
1080 ubi
->ubi_name
, ubi
->ref_count
);
1082 ubi_devices
[ubi_num
] = NULL
;
1083 spin_unlock(&ubi_devices_lock
);
1085 ubi_assert(ubi_num
== ubi
->ubi_num
);
1086 ubi_notify_all(ubi
, UBI_VOLUME_REMOVED
, NULL
);
1087 dbg_msg("detaching mtd%d from ubi%d", ubi
->mtd
->index
, ubi_num
);
1090 * Before freeing anything, we have to stop the background thread to
1091 * prevent it from doing anything on this device while we are freeing.
1093 unregister_reboot_notifier(&ubi
->reboot_notifier
);
1094 if (ubi
->bgt_thread
)
1095 kthread_stop(ubi
->bgt_thread
);
1098 * Get a reference to the device in order to prevent 'dev_release()'
1099 * from freeing the @ubi object.
1101 get_device(&ubi
->dev
);
1105 free_internal_volumes(ubi
);
1107 put_mtd_device(ubi
->mtd
);
1108 vfree(ubi
->peb_buf1
);
1109 vfree(ubi
->peb_buf2
);
1110 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
1111 vfree(ubi
->dbg_peb_buf
);
1113 ubi_msg("mtd%d is detached from ubi%d", ubi
->mtd
->index
, ubi
->ubi_num
);
1114 put_device(&ubi
->dev
);
1119 * open_mtd_by_chdev - open an MTD device by its character device node path.
1120 * @mtd_dev: MTD character device node path
1122 * This helper function opens an MTD device by its character node device path.
1123 * Returns MTD device description object in case of success and a negative
1124 * error code in case of failure.
1126 static struct mtd_info
* __init
open_mtd_by_chdev(const char *mtd_dev
)
1128 int err
, major
, minor
, mode
;
1131 /* Probably this is an MTD character device node path */
1132 err
= kern_path(mtd_dev
, LOOKUP_FOLLOW
, &path
);
1134 return ERR_PTR(err
);
1136 /* MTD device number is defined by the major / minor numbers */
1137 major
= imajor(path
.dentry
->d_inode
);
1138 minor
= iminor(path
.dentry
->d_inode
);
1139 mode
= path
.dentry
->d_inode
->i_mode
;
1141 if (major
!= MTD_CHAR_MAJOR
|| !S_ISCHR(mode
))
1142 return ERR_PTR(-EINVAL
);
1146 * Just do not think the "/dev/mtdrX" devices support is need,
1147 * so do not support them to avoid doing extra work.
1149 return ERR_PTR(-EINVAL
);
1151 return get_mtd_device(NULL
, minor
/ 2);
1155 * open_mtd_device - open MTD device by name, character device path, or number.
1156 * @mtd_dev: name, character device node path, or MTD device device number
1158 * This function tries to open and MTD device described by @mtd_dev string,
1159 * which is first treated as ASCII MTD device number, and if it is not true, it
1160 * is treated as MTD device name, and if that is also not true, it is treated
1161 * as MTD character device node path. Returns MTD device description object in
1162 * case of success and a negative error code in case of failure.
1164 static struct mtd_info
* __init
open_mtd_device(const char *mtd_dev
)
1166 struct mtd_info
*mtd
;
1170 mtd_num
= simple_strtoul(mtd_dev
, &endp
, 0);
1171 if (*endp
!= '\0' || mtd_dev
== endp
) {
1173 * This does not look like an ASCII integer, probably this is
1176 mtd
= get_mtd_device_nm(mtd_dev
);
1177 if (IS_ERR(mtd
) && PTR_ERR(mtd
) == -ENODEV
)
1178 /* Probably this is an MTD character device node path */
1179 mtd
= open_mtd_by_chdev(mtd_dev
);
1181 mtd
= get_mtd_device(NULL
, mtd_num
);
1186 static int __init
ubi_init(void)
1190 /* Ensure that EC and VID headers have correct size */
1191 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr
) != 64);
1192 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr
) != 64);
1194 if (mtd_devs
> UBI_MAX_DEVICES
) {
1195 ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES
);
1199 /* Create base sysfs directory and sysfs files */
1200 ubi_class
= class_create(THIS_MODULE
, UBI_NAME_STR
);
1201 if (IS_ERR(ubi_class
)) {
1202 err
= PTR_ERR(ubi_class
);
1203 ubi_err("cannot create UBI class");
1207 err
= class_create_file(ubi_class
, &ubi_version
);
1209 ubi_err("cannot create sysfs file");
1213 err
= misc_register(&ubi_ctrl_cdev
);
1215 ubi_err("cannot register device");
1219 ubi_wl_entry_slab
= kmem_cache_create("ubi_wl_entry_slab",
1220 sizeof(struct ubi_wl_entry
),
1222 if (!ubi_wl_entry_slab
)
1225 /* Attach MTD devices */
1226 for (i
= 0; i
< mtd_devs
; i
++) {
1227 struct mtd_dev_param
*p
= &mtd_dev_param
[i
];
1228 struct mtd_info
*mtd
;
1232 mtd
= open_mtd_device(p
->name
);
1238 mutex_lock(&ubi_devices_mutex
);
1239 err
= ubi_attach_mtd_dev(mtd
, UBI_DEV_NUM_AUTO
,
1241 mutex_unlock(&ubi_devices_mutex
);
1243 put_mtd_device(mtd
);
1244 ubi_err("cannot attach mtd%d", mtd
->index
);
1252 for (k
= 0; k
< i
; k
++)
1253 if (ubi_devices
[k
]) {
1254 mutex_lock(&ubi_devices_mutex
);
1255 ubi_detach_mtd_dev(ubi_devices
[k
]->ubi_num
, 1);
1256 mutex_unlock(&ubi_devices_mutex
);
1258 kmem_cache_destroy(ubi_wl_entry_slab
);
1260 misc_deregister(&ubi_ctrl_cdev
);
1262 class_remove_file(ubi_class
, &ubi_version
);
1264 class_destroy(ubi_class
);
1266 ubi_err("UBI error: cannot initialize UBI, error %d", err
);
1269 module_init(ubi_init
);
1271 static void __exit
ubi_exit(void)
1275 for (i
= 0; i
< UBI_MAX_DEVICES
; i
++)
1276 if (ubi_devices
[i
]) {
1277 mutex_lock(&ubi_devices_mutex
);
1278 ubi_detach_mtd_dev(ubi_devices
[i
]->ubi_num
, 1);
1279 mutex_unlock(&ubi_devices_mutex
);
1281 kmem_cache_destroy(ubi_wl_entry_slab
);
1282 misc_deregister(&ubi_ctrl_cdev
);
1283 class_remove_file(ubi_class
, &ubi_version
);
1284 class_destroy(ubi_class
);
1286 module_exit(ubi_exit
);
1289 * bytes_str_to_int - convert a number of bytes string into an integer.
1290 * @str: the string to convert
1292 * This function returns positive resulting integer in case of success and a
1293 * negative error code in case of failure.
1295 static int __init
bytes_str_to_int(const char *str
)
1298 unsigned long result
;
1300 result
= simple_strtoul(str
, &endp
, 0);
1301 if (str
== endp
|| result
>= INT_MAX
) {
1302 printk(KERN_ERR
"UBI error: incorrect bytes count: \"%s\"\n",
1314 if (endp
[1] == 'i' && endp
[2] == 'B')
1319 printk(KERN_ERR
"UBI error: incorrect bytes count: \"%s\"\n",
1328 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1329 * @val: the parameter value to parse
1332 * This function returns zero in case of success and a negative error code in
1335 static int __init
ubi_mtd_param_parse(const char *val
, struct kernel_param
*kp
)
1338 struct mtd_dev_param
*p
;
1339 char buf
[MTD_PARAM_LEN_MAX
];
1340 char *pbuf
= &buf
[0];
1341 char *tokens
[2] = {NULL
, NULL
};
1346 if (mtd_devs
== UBI_MAX_DEVICES
) {
1347 printk(KERN_ERR
"UBI error: too many parameters, max. is %d\n",
1352 len
= strnlen(val
, MTD_PARAM_LEN_MAX
);
1353 if (len
== MTD_PARAM_LEN_MAX
) {
1354 printk(KERN_ERR
"UBI error: parameter \"%s\" is too long, "
1355 "max. is %d\n", val
, MTD_PARAM_LEN_MAX
);
1360 printk(KERN_WARNING
"UBI warning: empty 'mtd=' parameter - "
1367 /* Get rid of the final newline */
1368 if (buf
[len
- 1] == '\n')
1369 buf
[len
- 1] = '\0';
1371 for (i
= 0; i
< 2; i
++)
1372 tokens
[i
] = strsep(&pbuf
, ",");
1375 printk(KERN_ERR
"UBI error: too many arguments at \"%s\"\n",
1380 p
= &mtd_dev_param
[mtd_devs
];
1381 strcpy(&p
->name
[0], tokens
[0]);
1384 p
->vid_hdr_offs
= bytes_str_to_int(tokens
[1]);
1386 if (p
->vid_hdr_offs
< 0)
1387 return p
->vid_hdr_offs
;
1393 module_param_call(mtd
, ubi_mtd_param_parse
, NULL
, NULL
, 000);
1394 MODULE_PARM_DESC(mtd
, "MTD devices to attach. Parameter format: "
1395 "mtd=<name|num|path>[,<vid_hdr_offs>].\n"
1396 "Multiple \"mtd\" parameters may be specified.\n"
1397 "MTD devices may be specified by their number, name, or "
1398 "path to the MTD character device node.\n"
1399 "Optional \"vid_hdr_offs\" parameter specifies UBI VID "
1400 "header position to be used by UBI.\n"
1401 "Example 1: mtd=/dev/mtd0 - attach MTD device "
1403 "Example 2: mtd=content,1984 mtd=4 - attach MTD device "
1404 "with name \"content\" using VID header offset 1984, and "
1405 "MTD device number 4 with default VID header offset.");
1407 MODULE_VERSION(__stringify(UBI_VERSION
));
1408 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1409 MODULE_AUTHOR("Artem Bityutskiy");
1410 MODULE_LICENSE("GPL");