master
1/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2/*
3 * Copyright © International Business Machines Corp., 2006
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 (Битюцкий Артём)
20 */
21
22#ifndef __UBI_USER_H__
23#define __UBI_USER_H__
24
25#include <linux/types.h>
26
27/*
28 * UBI device creation (the same as MTD device attachment)
29 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
30 *
31 * MTD devices may be attached using %UBI_IOCATT ioctl command of the UBI
32 * control device. The caller has to properly fill and pass
33 * &struct ubi_attach_req object - UBI will attach the MTD device specified in
34 * the request and return the newly created UBI device number as the ioctl
35 * return value.
36 *
37 * UBI device deletion (the same as MTD device detachment)
38 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
39 *
40 * An UBI device maybe deleted with %UBI_IOCDET ioctl command of the UBI
41 * control device.
42 *
43 * UBI volume creation
44 * ~~~~~~~~~~~~~~~~~~~
45 *
46 * UBI volumes are created via the %UBI_IOCMKVOL ioctl command of UBI character
47 * device. A &struct ubi_mkvol_req object has to be properly filled and a
48 * pointer to it has to be passed to the ioctl.
49 *
50 * UBI volume deletion
51 * ~~~~~~~~~~~~~~~~~~~
52 *
53 * To delete a volume, the %UBI_IOCRMVOL ioctl command of the UBI character
54 * device should be used. A pointer to the 32-bit volume ID hast to be passed
55 * to the ioctl.
56 *
57 * UBI volume re-size
58 * ~~~~~~~~~~~~~~~~~~
59 *
60 * To re-size a volume, the %UBI_IOCRSVOL ioctl command of the UBI character
61 * device should be used. A &struct ubi_rsvol_req object has to be properly
62 * filled and a pointer to it has to be passed to the ioctl.
63 *
64 * UBI volumes re-name
65 * ~~~~~~~~~~~~~~~~~~~
66 *
67 * To re-name several volumes atomically at one go, the %UBI_IOCRNVOL command
68 * of the UBI character device should be used. A &struct ubi_rnvol_req object
69 * has to be properly filled and a pointer to it has to be passed to the ioctl.
70 *
71 * UBI volume update
72 * ~~~~~~~~~~~~~~~~~
73 *
74 * Volume update should be done via the %UBI_IOCVOLUP ioctl command of the
75 * corresponding UBI volume character device. A pointer to a 64-bit update
76 * size should be passed to the ioctl. After this, UBI expects user to write
77 * this number of bytes to the volume character device. The update is finished
78 * when the claimed number of bytes is passed. So, the volume update sequence
79 * is something like:
80 *
81 * fd = open("/dev/my_volume");
82 * ioctl(fd, UBI_IOCVOLUP, &image_size);
83 * write(fd, buf, image_size);
84 * close(fd);
85 *
86 * Logical eraseblock erase
87 * ~~~~~~~~~~~~~~~~~~~~~~~~
88 *
89 * To erase a logical eraseblock, the %UBI_IOCEBER ioctl command of the
90 * corresponding UBI volume character device should be used. This command
91 * unmaps the requested logical eraseblock, makes sure the corresponding
92 * physical eraseblock is successfully erased, and returns.
93 *
94 * Atomic logical eraseblock change
95 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
96 *
97 * Atomic logical eraseblock change operation is called using the %UBI_IOCEBCH
98 * ioctl command of the corresponding UBI volume character device. A pointer to
99 * a &struct ubi_leb_change_req object has to be passed to the ioctl. Then the
100 * user is expected to write the requested amount of bytes (similarly to what
101 * should be done in case of the "volume update" ioctl).
102 *
103 * Logical eraseblock map
104 * ~~~~~~~~~~~~~~~~~~~~~
105 *
106 * To map a logical eraseblock to a physical eraseblock, the %UBI_IOCEBMAP
107 * ioctl command should be used. A pointer to a &struct ubi_map_req object is
108 * expected to be passed. The ioctl maps the requested logical eraseblock to
109 * a physical eraseblock and returns. Only non-mapped logical eraseblocks can
110 * be mapped. If the logical eraseblock specified in the request is already
111 * mapped to a physical eraseblock, the ioctl fails and returns error.
112 *
113 * Logical eraseblock unmap
114 * ~~~~~~~~~~~~~~~~~~~~~~~~
115 *
116 * To unmap a logical eraseblock to a physical eraseblock, the %UBI_IOCEBUNMAP
117 * ioctl command should be used. The ioctl unmaps the logical eraseblocks,
118 * schedules corresponding physical eraseblock for erasure, and returns. Unlike
119 * the "LEB erase" command, it does not wait for the physical eraseblock being
120 * erased. Note, the side effect of this is that if an unclean reboot happens
121 * after the unmap ioctl returns, you may find the LEB mapped again to the same
122 * physical eraseblock after the UBI is run again.
123 *
124 * Check if logical eraseblock is mapped
125 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
126 *
127 * To check if a logical eraseblock is mapped to a physical eraseblock, the
128 * %UBI_IOCEBISMAP ioctl command should be used. It returns %0 if the LEB is
129 * not mapped, and %1 if it is mapped.
130 *
131 * Set an UBI volume property
132 * ~~~~~~~~~~~~~~~~~~~~~~~~~
133 *
134 * To set an UBI volume property the %UBI_IOCSETPROP ioctl command should be
135 * used. A pointer to a &struct ubi_set_vol_prop_req object is expected to be
136 * passed. The object describes which property should be set, and to which value
137 * it should be set.
138 *
139 * Block devices on UBI volumes
140 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
141 *
142 * To create a R/O block device on top of an UBI volume the %UBI_IOCVOLCRBLK
143 * should be used. A pointer to a &struct ubi_blkcreate_req object is expected
144 * to be passed, which is not used and reserved for future usage.
145 *
146 * Conversely, to remove a block device the %UBI_IOCVOLRMBLK should be used,
147 * which takes no arguments.
148 */
149
150/*
151 * When a new UBI volume or UBI device is created, users may either specify the
152 * volume/device number they want to create or to let UBI automatically assign
153 * the number using these constants.
154 */
155#define UBI_VOL_NUM_AUTO (-1)
156#define UBI_DEV_NUM_AUTO (-1)
157
158/* Maximum volume name length */
159#define UBI_MAX_VOLUME_NAME 127
160
161/* ioctl commands of UBI character devices */
162
163#define UBI_IOC_MAGIC 'o'
164
165/* Create an UBI volume */
166#define UBI_IOCMKVOL _IOW(UBI_IOC_MAGIC, 0, struct ubi_mkvol_req)
167/* Remove an UBI volume */
168#define UBI_IOCRMVOL _IOW(UBI_IOC_MAGIC, 1, __s32)
169/* Re-size an UBI volume */
170#define UBI_IOCRSVOL _IOW(UBI_IOC_MAGIC, 2, struct ubi_rsvol_req)
171/* Re-name volumes */
172#define UBI_IOCRNVOL _IOW(UBI_IOC_MAGIC, 3, struct ubi_rnvol_req)
173
174/* Read the specified PEB and scrub it if there are bitflips */
175#define UBI_IOCRPEB _IOW(UBI_IOC_MAGIC, 4, __s32)
176/* Force scrubbing on the specified PEB */
177#define UBI_IOCSPEB _IOW(UBI_IOC_MAGIC, 5, __s32)
178/* Read detailed device erase counter information */
179#define UBI_IOCECNFO _IOWR(UBI_IOC_MAGIC, 6, struct ubi_ecinfo_req)
180
181/* ioctl commands of the UBI control character device */
182
183#define UBI_CTRL_IOC_MAGIC 'o'
184
185/* Attach an MTD device */
186#define UBI_IOCATT _IOW(UBI_CTRL_IOC_MAGIC, 64, struct ubi_attach_req)
187/* Detach an MTD device */
188#define UBI_IOCDET _IOW(UBI_CTRL_IOC_MAGIC, 65, __s32)
189
190/* ioctl commands of UBI volume character devices */
191
192#define UBI_VOL_IOC_MAGIC 'O'
193
194/* Start UBI volume update
195 * Note: This actually takes a pointer (__s64*), but we can't change
196 * that without breaking the ABI on 32bit systems
197 */
198#define UBI_IOCVOLUP _IOW(UBI_VOL_IOC_MAGIC, 0, __s64)
199/* LEB erasure command, used for debugging, disabled by default */
200#define UBI_IOCEBER _IOW(UBI_VOL_IOC_MAGIC, 1, __s32)
201/* Atomic LEB change command */
202#define UBI_IOCEBCH _IOW(UBI_VOL_IOC_MAGIC, 2, __s32)
203/* Map LEB command */
204#define UBI_IOCEBMAP _IOW(UBI_VOL_IOC_MAGIC, 3, struct ubi_map_req)
205/* Unmap LEB command */
206#define UBI_IOCEBUNMAP _IOW(UBI_VOL_IOC_MAGIC, 4, __s32)
207/* Check if LEB is mapped command */
208#define UBI_IOCEBISMAP _IOR(UBI_VOL_IOC_MAGIC, 5, __s32)
209/* Set an UBI volume property */
210#define UBI_IOCSETVOLPROP _IOW(UBI_VOL_IOC_MAGIC, 6, \
211 struct ubi_set_vol_prop_req)
212/* Create a R/O block device on top of an UBI volume */
213#define UBI_IOCVOLCRBLK _IOW(UBI_VOL_IOC_MAGIC, 7, struct ubi_blkcreate_req)
214/* Remove the R/O block device */
215#define UBI_IOCVOLRMBLK _IO(UBI_VOL_IOC_MAGIC, 8)
216
217/* Maximum MTD device name length supported by UBI */
218#define MAX_UBI_MTD_NAME_LEN 127
219
220/* Maximum amount of UBI volumes that can be re-named at one go */
221#define UBI_MAX_RNVOL 32
222
223/*
224 * UBI volume type constants.
225 *
226 * @UBI_DYNAMIC_VOLUME: dynamic volume
227 * @UBI_STATIC_VOLUME: static volume
228 */
229enum {
230 UBI_DYNAMIC_VOLUME = 3,
231 UBI_STATIC_VOLUME = 4,
232};
233
234/*
235 * UBI set volume property ioctl constants.
236 *
237 * @UBI_VOL_PROP_DIRECT_WRITE: allow (any non-zero value) or disallow (value 0)
238 * user to directly write and erase individual
239 * eraseblocks on dynamic volumes
240 */
241enum {
242 UBI_VOL_PROP_DIRECT_WRITE = 1,
243};
244
245/**
246 * struct ubi_attach_req - attach MTD device request.
247 * @ubi_num: UBI device number to create
248 * @mtd_num: MTD device number to attach
249 * @vid_hdr_offset: VID header offset (use defaults if %0)
250 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
251 * @padding: reserved for future, not used, has to be zeroed
252 * @disable_fm: whether disable fastmap
253 * @need_resv_pool: whether reserve free pebs for filling pool/wl_pool
254 *
255 * This data structure is used to specify MTD device UBI has to attach and the
256 * parameters it has to use. The number which should be assigned to the new UBI
257 * device is passed in @ubi_num. UBI may automatically assign the number if
258 * @UBI_DEV_NUM_AUTO is passed. In this case, the device number is returned in
259 * @ubi_num.
260 *
261 * Most applications should pass %0 in @vid_hdr_offset to make UBI use default
262 * offset of the VID header within physical eraseblocks. The default offset is
263 * the next min. I/O unit after the EC header. For example, it will be offset
264 * 512 in case of a 512 bytes page NAND flash with no sub-page support. Or
265 * it will be 512 in case of a 2KiB page NAND flash with 4 512-byte sub-pages.
266 *
267 * But in rare cases, if this optimizes things, the VID header may be placed to
268 * a different offset. For example, the boot-loader might do things faster if
269 * the VID header sits at the end of the first 2KiB NAND page with 4 sub-pages.
270 * As the boot-loader would not normally need to read EC headers (unless it
271 * needs UBI in RW mode), it might be faster to calculate ECC. This is weird
272 * example, but it real-life example. So, in this example, @vid_hdr_offer would
273 * be 2KiB-64 bytes = 1984. Note, that this position is not even 512-bytes
274 * aligned, which is OK, as UBI is clever enough to realize this is 4th
275 * sub-page of the first page and add needed padding.
276 *
277 * The @max_beb_per1024 is the maximum amount of bad PEBs UBI expects on the
278 * UBI device per 1024 eraseblocks. This value is often given in an other form
279 * in the NAND datasheet (min NVB i.e. minimal number of valid blocks). The
280 * maximum expected bad eraseblocks per 1024 is then:
281 * 1024 * (1 - MinNVB / MaxNVB)
282 * Which gives 20 for most NAND devices. This limit is used in order to derive
283 * amount of eraseblock UBI reserves for handling new bad blocks. If the device
284 * has more bad eraseblocks than this limit, UBI does not reserve any physical
285 * eraseblocks for new bad eraseblocks, but attempts to use available
286 * eraseblocks (if any). The accepted range is 0-768. If 0 is given, the
287 * default kernel value of %CONFIG_MTD_UBI_BEB_LIMIT will be used.
288 *
289 * If @disable_fm is not zero, ubi doesn't create new fastmap even the module
290 * param 'fm_autoconvert' is set, and existed old fastmap will be destroyed
291 * after doing full scanning.
292 */
293struct ubi_attach_req {
294 __s32 ubi_num;
295 __s32 mtd_num;
296 __s32 vid_hdr_offset;
297 __s16 max_beb_per1024;
298 __s8 disable_fm;
299 __s8 need_resv_pool;
300 __s8 padding[8];
301};
302
303/*
304 * UBI volume flags.
305 *
306 * @UBI_VOL_SKIP_CRC_CHECK_FLG: skip the CRC check done on a static volume at
307 * open time. Only valid for static volumes and
308 * should only be used if the volume user has a
309 * way to verify data integrity
310 */
311enum {
312 UBI_VOL_SKIP_CRC_CHECK_FLG = 0x1,
313};
314
315#define UBI_VOL_VALID_FLGS (UBI_VOL_SKIP_CRC_CHECK_FLG)
316
317/**
318 * struct ubi_mkvol_req - volume description data structure used in
319 * volume creation requests.
320 * @vol_id: volume number
321 * @alignment: volume alignment
322 * @bytes: volume size in bytes
323 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
324 * @flags: volume flags (%UBI_VOL_SKIP_CRC_CHECK_FLG)
325 * @name_len: volume name length
326 * @padding2: reserved for future, not used, has to be zeroed
327 * @name: volume name
328 *
329 * This structure is used by user-space programs when creating new volumes. The
330 * @used_bytes field is only necessary when creating static volumes.
331 *
332 * The @alignment field specifies the required alignment of the volume logical
333 * eraseblock. This means, that the size of logical eraseblocks will be aligned
334 * to this number, i.e.,
335 * (UBI device logical eraseblock size) mod (@alignment) = 0.
336 *
337 * To put it differently, the logical eraseblock of this volume may be slightly
338 * shortened in order to make it properly aligned. The alignment has to be
339 * multiple of the flash minimal input/output unit, or %1 to utilize the entire
340 * available space of logical eraseblocks.
341 *
342 * The @alignment field may be useful, for example, when one wants to maintain
343 * a block device on top of an UBI volume. In this case, it is desirable to fit
344 * an integer number of blocks in logical eraseblocks of this UBI volume. With
345 * alignment it is possible to update this volume using plane UBI volume image
346 * BLOBs, without caring about how to properly align them.
347 */
348struct ubi_mkvol_req {
349 __s32 vol_id;
350 __s32 alignment;
351 __s64 bytes;
352 __s8 vol_type;
353 __u8 flags;
354 __s16 name_len;
355 __s8 padding2[4];
356 char name[UBI_MAX_VOLUME_NAME + 1];
357} __attribute__((packed));
358
359/**
360 * struct ubi_rsvol_req - a data structure used in volume re-size requests.
361 * @vol_id: ID of the volume to re-size
362 * @bytes: new size of the volume in bytes
363 *
364 * Re-sizing is possible for both dynamic and static volumes. But while dynamic
365 * volumes may be re-sized arbitrarily, static volumes cannot be made to be
366 * smaller than the number of bytes they bear. To arbitrarily shrink a static
367 * volume, it must be wiped out first (by means of volume update operation with
368 * zero number of bytes).
369 */
370struct ubi_rsvol_req {
371 __s64 bytes;
372 __s32 vol_id;
373} __attribute__((packed));
374
375/**
376 * struct ubi_rnvol_req - volumes re-name request.
377 * @count: count of volumes to re-name
378 * @padding1: reserved for future, not used, has to be zeroed
379 * @vol_id: ID of the volume to re-name
380 * @name_len: name length
381 * @padding2: reserved for future, not used, has to be zeroed
382 * @name: new volume name
383 *
384 * UBI allows to re-name up to %32 volumes at one go. The count of volumes to
385 * re-name is specified in the @count field. The ID of the volumes to re-name
386 * and the new names are specified in the @vol_id and @name fields.
387 *
388 * The UBI volume re-name operation is atomic, which means that should power cut
389 * happen, the volumes will have either old name or new name. So the possible
390 * use-cases of this command is atomic upgrade. Indeed, to upgrade, say, volumes
391 * A and B one may create temporary volumes %A1 and %B1 with the new contents,
392 * then atomically re-name A1->A and B1->B, in which case old %A and %B will
393 * be removed.
394 *
395 * If it is not desirable to remove old A and B, the re-name request has to
396 * contain 4 entries: A1->A, A->A1, B1->B, B->B1, in which case old A1 and B1
397 * become A and B, and old A and B will become A1 and B1.
398 *
399 * It is also OK to request: A1->A, A1->X, B1->B, B->Y, in which case old A1
400 * and B1 become A and B, and old A and B become X and Y.
401 *
402 * In other words, in case of re-naming into an existing volume name, the
403 * existing volume is removed, unless it is re-named as well at the same
404 * re-name request.
405 */
406struct ubi_rnvol_req {
407 __s32 count;
408 __s8 padding1[12];
409 struct {
410 __s32 vol_id;
411 __s16 name_len;
412 __s8 padding2[2];
413 char name[UBI_MAX_VOLUME_NAME + 1];
414 } ents[UBI_MAX_RNVOL];
415} __attribute__((packed));
416
417/**
418 * struct ubi_ecinfo_req - a data structure used for requesting and receiving
419 * erase block counter information from a UBI device.
420 *
421 * @start: index of first physical erase block to read (in)
422 * @length: number of erase counters to read (in)
423 * @read_length: number of erase counters that was actually read (out)
424 * @padding: reserved for future, not used, has to be zeroed
425 * @erase_counters: array of erase counter values (out)
426 *
427 * This structure is used to retrieve erase counter information for a specified
428 * range of PEBs on a UBI device.
429 * Erase counters are read from @start and attempts to read @length number of
430 * erase counters.
431 * The retrieved values are stored in the @erase_counters array. It is the
432 * responsibility of the caller to allocate enough memory for storing @length
433 * elements in the @erase_counters array.
434 * If a block is bad or if the erase counter is unknown the corresponding value
435 * in the array will be set to -1.
436 * The @read_length field will indicate the number of erase counters actually
437 * read. Typically @read_length will be limited due to memory or the number of
438 * PEBs on the UBI device.
439 */
440struct ubi_ecinfo_req {
441 __s32 start;
442 __s32 length;
443 __s32 read_length;
444 __s8 padding[16];
445 __s32 erase_counters[];
446} __attribute__((packed));
447
448/**
449 * struct ubi_leb_change_req - a data structure used in atomic LEB change
450 * requests.
451 * @lnum: logical eraseblock number to change
452 * @bytes: how many bytes will be written to the logical eraseblock
453 * @dtype: pass "3" for better compatibility with old kernels
454 * @padding: reserved for future, not used, has to be zeroed
455 *
456 * The @dtype field used to inform UBI about what kind of data will be written
457 * to the LEB: long term (value 1), short term (value 2), unknown (value 3).
458 * UBI tried to pick a PEB with lower erase counter for short term data and a
459 * PEB with higher erase counter for long term data. But this was not really
460 * used because users usually do not know this and could easily mislead UBI. We
461 * removed this feature in May 2012. UBI currently just ignores the @dtype
462 * field. But for better compatibility with older kernels it is recommended to
463 * set @dtype to 3 (unknown).
464 */
465struct ubi_leb_change_req {
466 __s32 lnum;
467 __s32 bytes;
468 __s8 dtype; /* obsolete, do not use! */
469 __s8 padding[7];
470} __attribute__((packed));
471
472/**
473 * struct ubi_map_req - a data structure used in map LEB requests.
474 * @dtype: pass "3" for better compatibility with old kernels
475 * @lnum: logical eraseblock number to unmap
476 * @padding: reserved for future, not used, has to be zeroed
477 */
478struct ubi_map_req {
479 __s32 lnum;
480 __s8 dtype; /* obsolete, do not use! */
481 __s8 padding[3];
482} __attribute__((packed));
483
484
485/**
486 * struct ubi_set_vol_prop_req - a data structure used to set an UBI volume
487 * property.
488 * @property: property to set (%UBI_VOL_PROP_DIRECT_WRITE)
489 * @padding: reserved for future, not used, has to be zeroed
490 * @value: value to set
491 */
492struct ubi_set_vol_prop_req {
493 __u8 property;
494 __u8 padding[7];
495 __u64 value;
496} __attribute__((packed));
497
498/**
499 * struct ubi_blkcreate_req - a data structure used in block creation requests.
500 * @padding: reserved for future, not used, has to be zeroed
501 */
502struct ubi_blkcreate_req {
503 __s8 padding[128];
504} __attribute__((packed));
505
506#endif /* __UBI_USER_H__ */