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 (���������������� ����������)
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
179/* ioctl commands of the UBI control character device */
180
181#define UBI_CTRL_IOC_MAGIC 'o'
182
183/* Attach an MTD device */
184#define UBI_IOCATT _IOW(UBI_CTRL_IOC_MAGIC, 64, struct ubi_attach_req)
185/* Detach an MTD device */
186#define UBI_IOCDET _IOW(UBI_CTRL_IOC_MAGIC, 65, __s32)
187
188/* ioctl commands of UBI volume character devices */
189
190#define UBI_VOL_IOC_MAGIC 'O'
191
192/* Start UBI volume update
193 * Note: This actually takes a pointer (__s64*), but we can't change
194 *       that without breaking the ABI on 32bit systems
195 */
196#define UBI_IOCVOLUP _IOW(UBI_VOL_IOC_MAGIC, 0, __s64)
197/* LEB erasure command, used for debugging, disabled by default */
198#define UBI_IOCEBER _IOW(UBI_VOL_IOC_MAGIC, 1, __s32)
199/* Atomic LEB change command */
200#define UBI_IOCEBCH _IOW(UBI_VOL_IOC_MAGIC, 2, __s32)
201/* Map LEB command */
202#define UBI_IOCEBMAP _IOW(UBI_VOL_IOC_MAGIC, 3, struct ubi_map_req)
203/* Unmap LEB command */
204#define UBI_IOCEBUNMAP _IOW(UBI_VOL_IOC_MAGIC, 4, __s32)
205/* Check if LEB is mapped command */
206#define UBI_IOCEBISMAP _IOR(UBI_VOL_IOC_MAGIC, 5, __s32)
207/* Set an UBI volume property */
208#define UBI_IOCSETVOLPROP _IOW(UBI_VOL_IOC_MAGIC, 6, \
209			       struct ubi_set_vol_prop_req)
210/* Create a R/O block device on top of an UBI volume */
211#define UBI_IOCVOLCRBLK _IOW(UBI_VOL_IOC_MAGIC, 7, struct ubi_blkcreate_req)
212/* Remove the R/O block device */
213#define UBI_IOCVOLRMBLK _IO(UBI_VOL_IOC_MAGIC, 8)
214
215/* Maximum MTD device name length supported by UBI */
216#define MAX_UBI_MTD_NAME_LEN 127
217
218/* Maximum amount of UBI volumes that can be re-named at one go */
219#define UBI_MAX_RNVOL 32
220
221/*
222 * UBI volume type constants.
223 *
224 * @UBI_DYNAMIC_VOLUME: dynamic volume
225 * @UBI_STATIC_VOLUME:  static volume
226 */
227enum {
228	UBI_DYNAMIC_VOLUME = 3,
229	UBI_STATIC_VOLUME  = 4,
230};
231
232/*
233 * UBI set volume property ioctl constants.
234 *
235 * @UBI_VOL_PROP_DIRECT_WRITE: allow (any non-zero value) or disallow (value 0)
236 *                             user to directly write and erase individual
237 *                             eraseblocks on dynamic volumes
238 */
239enum {
240	UBI_VOL_PROP_DIRECT_WRITE = 1,
241};
242
243/**
244 * struct ubi_attach_req - attach MTD device request.
245 * @ubi_num: UBI device number to create
246 * @mtd_num: MTD device number to attach
247 * @vid_hdr_offset: VID header offset (use defaults if %0)
248 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
249 * @padding: reserved for future, not used, has to be zeroed
250 * @disable_fm: whether disable fastmap
251 * @need_resv_pool: whether reserve free pebs for filling pool/wl_pool
252 *
253 * This data structure is used to specify MTD device UBI has to attach and the
254 * parameters it has to use. The number which should be assigned to the new UBI
255 * device is passed in @ubi_num. UBI may automatically assign the number if
256 * @UBI_DEV_NUM_AUTO is passed. In this case, the device number is returned in
257 * @ubi_num.
258 *
259 * Most applications should pass %0 in @vid_hdr_offset to make UBI use default
260 * offset of the VID header within physical eraseblocks. The default offset is
261 * the next min. I/O unit after the EC header. For example, it will be offset
262 * 512 in case of a 512 bytes page NAND flash with no sub-page support. Or
263 * it will be 512 in case of a 2KiB page NAND flash with 4 512-byte sub-pages.
264 *
265 * But in rare cases, if this optimizes things, the VID header may be placed to
266 * a different offset. For example, the boot-loader might do things faster if
267 * the VID header sits at the end of the first 2KiB NAND page with 4 sub-pages.
268 * As the boot-loader would not normally need to read EC headers (unless it
269 * needs UBI in RW mode), it might be faster to calculate ECC. This is weird
270 * example, but it real-life example. So, in this example, @vid_hdr_offer would
271 * be 2KiB-64 bytes = 1984. Note, that this position is not even 512-bytes
272 * aligned, which is OK, as UBI is clever enough to realize this is 4th
273 * sub-page of the first page and add needed padding.
274 *
275 * The @max_beb_per1024 is the maximum amount of bad PEBs UBI expects on the
276 * UBI device per 1024 eraseblocks.  This value is often given in an other form
277 * in the NAND datasheet (min NVB i.e. minimal number of valid blocks). The
278 * maximum expected bad eraseblocks per 1024 is then:
279 *    1024 * (1 - MinNVB / MaxNVB)
280 * Which gives 20 for most NAND devices.  This limit is used in order to derive
281 * amount of eraseblock UBI reserves for handling new bad blocks. If the device
282 * has more bad eraseblocks than this limit, UBI does not reserve any physical
283 * eraseblocks for new bad eraseblocks, but attempts to use available
284 * eraseblocks (if any). The accepted range is 0-768. If 0 is given, the
285 * default kernel value of %CONFIG_MTD_UBI_BEB_LIMIT will be used.
286 *
287 * If @disable_fm is not zero, ubi doesn't create new fastmap even the module
288 * param 'fm_autoconvert' is set, and existed old fastmap will be destroyed
289 * after doing full scanning.
290 */
291struct ubi_attach_req {
292	__s32 ubi_num;
293	__s32 mtd_num;
294	__s32 vid_hdr_offset;
295	__s16 max_beb_per1024;
296	__s8 disable_fm;
297	__s8 need_resv_pool;
298	__s8 padding[8];
299};
300
301/*
302 * UBI volume flags.
303 *
304 * @UBI_VOL_SKIP_CRC_CHECK_FLG: skip the CRC check done on a static volume at
305 *				open time. Only valid for static volumes and
306 *				should only be used if the volume user has a
307 *				way to verify data integrity
308 */
309enum {
310	UBI_VOL_SKIP_CRC_CHECK_FLG = 0x1,
311};
312
313#define UBI_VOL_VALID_FLGS	(UBI_VOL_SKIP_CRC_CHECK_FLG)
314
315/**
316 * struct ubi_mkvol_req - volume description data structure used in
317 *                        volume creation requests.
318 * @vol_id: volume number
319 * @alignment: volume alignment
320 * @bytes: volume size in bytes
321 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
322 * @flags: volume flags (%UBI_VOL_SKIP_CRC_CHECK_FLG)
323 * @name_len: volume name length
324 * @padding2: reserved for future, not used, has to be zeroed
325 * @name: volume name
326 *
327 * This structure is used by user-space programs when creating new volumes. The
328 * @used_bytes field is only necessary when creating static volumes.
329 *
330 * The @alignment field specifies the required alignment of the volume logical
331 * eraseblock. This means, that the size of logical eraseblocks will be aligned
332 * to this number, i.e.,
333 *	(UBI device logical eraseblock size) mod (@alignment) = 0.
334 *
335 * To put it differently, the logical eraseblock of this volume may be slightly
336 * shortened in order to make it properly aligned. The alignment has to be
337 * multiple of the flash minimal input/output unit, or %1 to utilize the entire
338 * available space of logical eraseblocks.
339 *
340 * The @alignment field may be useful, for example, when one wants to maintain
341 * a block device on top of an UBI volume. In this case, it is desirable to fit
342 * an integer number of blocks in logical eraseblocks of this UBI volume. With
343 * alignment it is possible to update this volume using plane UBI volume image
344 * BLOBs, without caring about how to properly align them.
345 */
346struct ubi_mkvol_req {
347	__s32 vol_id;
348	__s32 alignment;
349	__s64 bytes;
350	__s8 vol_type;
351	__u8 flags;
352	__s16 name_len;
353	__s8 padding2[4];
354	char name[UBI_MAX_VOLUME_NAME + 1];
355} __packed;
356
357/**
358 * struct ubi_rsvol_req - a data structure used in volume re-size requests.
359 * @vol_id: ID of the volume to re-size
360 * @bytes: new size of the volume in bytes
361 *
362 * Re-sizing is possible for both dynamic and static volumes. But while dynamic
363 * volumes may be re-sized arbitrarily, static volumes cannot be made to be
364 * smaller than the number of bytes they bear. To arbitrarily shrink a static
365 * volume, it must be wiped out first (by means of volume update operation with
366 * zero number of bytes).
367 */
368struct ubi_rsvol_req {
369	__s64 bytes;
370	__s32 vol_id;
371} __packed;
372
373/**
374 * struct ubi_rnvol_req - volumes re-name request.
375 * @count: count of volumes to re-name
376 * @padding1:  reserved for future, not used, has to be zeroed
377 * @vol_id: ID of the volume to re-name
378 * @name_len: name length
379 * @padding2:  reserved for future, not used, has to be zeroed
380 * @name: new volume name
381 *
382 * UBI allows to re-name up to %32 volumes at one go. The count of volumes to
383 * re-name is specified in the @count field. The ID of the volumes to re-name
384 * and the new names are specified in the @vol_id and @name fields.
385 *
386 * The UBI volume re-name operation is atomic, which means that should power cut
387 * happen, the volumes will have either old name or new name. So the possible
388 * use-cases of this command is atomic upgrade. Indeed, to upgrade, say, volumes
389 * A and B one may create temporary volumes %A1 and %B1 with the new contents,
390 * then atomically re-name A1->A and B1->B, in which case old %A and %B will
391 * be removed.
392 *
393 * If it is not desirable to remove old A and B, the re-name request has to
394 * contain 4 entries: A1->A, A->A1, B1->B, B->B1, in which case old A1 and B1
395 * become A and B, and old A and B will become A1 and B1.
396 *
397 * It is also OK to request: A1->A, A1->X, B1->B, B->Y, in which case old A1
398 * and B1 become A and B, and old A and B become X and Y.
399 *
400 * In other words, in case of re-naming into an existing volume name, the
401 * existing volume is removed, unless it is re-named as well at the same
402 * re-name request.
403 */
404struct ubi_rnvol_req {
405	__s32 count;
406	__s8 padding1[12];
407	struct {
408		__s32 vol_id;
409		__s16 name_len;
410		__s8  padding2[2];
411		char    name[UBI_MAX_VOLUME_NAME + 1];
412	} ents[UBI_MAX_RNVOL];
413} __packed;
414
415/**
416 * struct ubi_leb_change_req - a data structure used in atomic LEB change
417 *                             requests.
418 * @lnum: logical eraseblock number to change
419 * @bytes: how many bytes will be written to the logical eraseblock
420 * @dtype: pass "3" for better compatibility with old kernels
421 * @padding: reserved for future, not used, has to be zeroed
422 *
423 * The @dtype field used to inform UBI about what kind of data will be written
424 * to the LEB: long term (value 1), short term (value 2), unknown (value 3).
425 * UBI tried to pick a PEB with lower erase counter for short term data and a
426 * PEB with higher erase counter for long term data. But this was not really
427 * used because users usually do not know this and could easily mislead UBI. We
428 * removed this feature in May 2012. UBI currently just ignores the @dtype
429 * field. But for better compatibility with older kernels it is recommended to
430 * set @dtype to 3 (unknown).
431 */
432struct ubi_leb_change_req {
433	__s32 lnum;
434	__s32 bytes;
435	__s8  dtype; /* obsolete, do not use! */
436	__s8  padding[7];
437} __packed;
438
439/**
440 * struct ubi_map_req - a data structure used in map LEB requests.
441 * @dtype: pass "3" for better compatibility with old kernels
442 * @lnum: logical eraseblock number to unmap
443 * @padding: reserved for future, not used, has to be zeroed
444 */
445struct ubi_map_req {
446	__s32 lnum;
447	__s8  dtype; /* obsolete, do not use! */
448	__s8  padding[3];
449} __packed;
450
451
452/**
453 * struct ubi_set_vol_prop_req - a data structure used to set an UBI volume
454 *                               property.
455 * @property: property to set (%UBI_VOL_PROP_DIRECT_WRITE)
456 * @padding: reserved for future, not used, has to be zeroed
457 * @value: value to set
458 */
459struct ubi_set_vol_prop_req {
460	__u8  property;
461	__u8  padding[7];
462	__u64 value;
463}  __packed;
464
465/**
466 * struct ubi_blkcreate_req - a data structure used in block creation requests.
467 * @padding: reserved for future, not used, has to be zeroed
468 */
469struct ubi_blkcreate_req {
470	__s8  padding[128];
471}  __packed;
472
473#endif /* __UBI_USER_H__ */
474