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1/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */2/*3 * Copyright © International Business Machines Corp., 20064 *5 * This program is free software; you can redistribute it and/or modify6 * it under the terms of the GNU General Public License as published by7 * the Free Software Foundation; either version 2 of the License, or8 * (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 of12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See13 * the GNU General Public License for more details.14 *15 * You should have received a copy of the GNU General Public License16 * along with this program; if not, write to the Free Software17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA18 *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 UBI32 * control device. The caller has to properly fill and pass33 * &struct ubi_attach_req object - UBI will attach the MTD device specified in34 * the request and return the newly created UBI device number as the ioctl35 * 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 UBI41 * control device.42 *43 * UBI volume creation44 * ~~~~~~~~~~~~~~~~~~~45 *46 * UBI volumes are created via the %UBI_IOCMKVOL ioctl command of UBI character47 * device. A &struct ubi_mkvol_req object has to be properly filled and a48 * pointer to it has to be passed to the ioctl.49 *50 * UBI volume deletion51 * ~~~~~~~~~~~~~~~~~~~52 *53 * To delete a volume, the %UBI_IOCRMVOL ioctl command of the UBI character54 * device should be used. A pointer to the 32-bit volume ID hast to be passed55 * to the ioctl.56 *57 * UBI volume re-size58 * ~~~~~~~~~~~~~~~~~~59 *60 * To re-size a volume, the %UBI_IOCRSVOL ioctl command of the UBI character61 * device should be used. A &struct ubi_rsvol_req object has to be properly62 * filled and a pointer to it has to be passed to the ioctl.63 *64 * UBI volumes re-name65 * ~~~~~~~~~~~~~~~~~~~66 *67 * To re-name several volumes atomically at one go, the %UBI_IOCRNVOL command68 * of the UBI character device should be used. A &struct ubi_rnvol_req object69 * has to be properly filled and a pointer to it has to be passed to the ioctl.70 *71 * UBI volume update72 * ~~~~~~~~~~~~~~~~~73 *74 * Volume update should be done via the %UBI_IOCVOLUP ioctl command of the75 * corresponding UBI volume character device. A pointer to a 64-bit update76 * size should be passed to the ioctl. After this, UBI expects user to write77 * this number of bytes to the volume character device. The update is finished78 * when the claimed number of bytes is passed. So, the volume update sequence79 * 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 erase87 * ~~~~~~~~~~~~~~~~~~~~~~~~88 *89 * To erase a logical eraseblock, the %UBI_IOCEBER ioctl command of the90 * corresponding UBI volume character device should be used. This command91 * unmaps the requested logical eraseblock, makes sure the corresponding92 * physical eraseblock is successfully erased, and returns.93 *94 * Atomic logical eraseblock change95 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~96 *97 * Atomic logical eraseblock change operation is called using the %UBI_IOCEBCH98 * ioctl command of the corresponding UBI volume character device. A pointer to99 * a &struct ubi_leb_change_req object has to be passed to the ioctl. Then the100 * user is expected to write the requested amount of bytes (similarly to what101 * should be done in case of the "volume update" ioctl).102 *103 * Logical eraseblock map104 * ~~~~~~~~~~~~~~~~~~~~~105 *106 * To map a logical eraseblock to a physical eraseblock, the %UBI_IOCEBMAP107 * ioctl command should be used. A pointer to a &struct ubi_map_req object is108 * expected to be passed. The ioctl maps the requested logical eraseblock to109 * a physical eraseblock and returns. Only non-mapped logical eraseblocks can110 * be mapped. If the logical eraseblock specified in the request is already111 * mapped to a physical eraseblock, the ioctl fails and returns error.112 *113 * Logical eraseblock unmap114 * ~~~~~~~~~~~~~~~~~~~~~~~~115 *116 * To unmap a logical eraseblock to a physical eraseblock, the %UBI_IOCEBUNMAP117 * ioctl command should be used. The ioctl unmaps the logical eraseblocks,118 * schedules corresponding physical eraseblock for erasure, and returns. Unlike119 * the "LEB erase" command, it does not wait for the physical eraseblock being120 * erased. Note, the side effect of this is that if an unclean reboot happens121 * after the unmap ioctl returns, you may find the LEB mapped again to the same122 * physical eraseblock after the UBI is run again.123 *124 * Check if logical eraseblock is mapped125 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~126 *127 * To check if a logical eraseblock is mapped to a physical eraseblock, the128 * %UBI_IOCEBISMAP ioctl command should be used. It returns %0 if the LEB is129 * not mapped, and %1 if it is mapped.130 *131 * Set an UBI volume property132 * ~~~~~~~~~~~~~~~~~~~~~~~~~133 *134 * To set an UBI volume property the %UBI_IOCSETPROP ioctl command should be135 * used. A pointer to a &struct ubi_set_vol_prop_req object is expected to be136 * passed. The object describes which property should be set, and to which value137 * it should be set.138 *139 * Block devices on UBI volumes140 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~141 *142 * To create a R/O block device on top of an UBI volume the %UBI_IOCVOLCRBLK143 * should be used. A pointer to a &struct ubi_blkcreate_req object is expected144 * 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 the152 * volume/device number they want to create or to let UBI automatically assign153 * 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 127160 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 update193 * Note: This actually takes a pointer (__s64*), but we can't change194 * that without breaking the ABI on 32bit systems195 */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 127217 218/* Maximum amount of UBI volumes that can be re-named at one go */219#define UBI_MAX_RNVOL 32220 221/*222 * UBI volume type constants.223 *224 * @UBI_DYNAMIC_VOLUME: dynamic volume225 * @UBI_STATIC_VOLUME: static volume226 */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 individual237 * eraseblocks on dynamic volumes238 */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 create246 * @mtd_num: MTD device number to attach247 * @vid_hdr_offset: VID header offset (use defaults if %0)248 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs249 * @padding: reserved for future, not used, has to be zeroed250 * @disable_fm: whether disable fastmap251 * @need_resv_pool: whether reserve free pebs for filling pool/wl_pool252 *253 * This data structure is used to specify MTD device UBI has to attach and the254 * parameters it has to use. The number which should be assigned to the new UBI255 * device is passed in @ubi_num. UBI may automatically assign the number if256 * @UBI_DEV_NUM_AUTO is passed. In this case, the device number is returned in257 * @ubi_num.258 *259 * Most applications should pass %0 in @vid_hdr_offset to make UBI use default260 * offset of the VID header within physical eraseblocks. The default offset is261 * the next min. I/O unit after the EC header. For example, it will be offset262 * 512 in case of a 512 bytes page NAND flash with no sub-page support. Or263 * 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 to266 * a different offset. For example, the boot-loader might do things faster if267 * 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 it269 * needs UBI in RW mode), it might be faster to calculate ECC. This is weird270 * example, but it real-life example. So, in this example, @vid_hdr_offer would271 * be 2KiB-64 bytes = 1984. Note, that this position is not even 512-bytes272 * aligned, which is OK, as UBI is clever enough to realize this is 4th273 * 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 the276 * UBI device per 1024 eraseblocks. This value is often given in an other form277 * in the NAND datasheet (min NVB i.e. minimal number of valid blocks). The278 * 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 derive281 * amount of eraseblock UBI reserves for handling new bad blocks. If the device282 * has more bad eraseblocks than this limit, UBI does not reserve any physical283 * eraseblocks for new bad eraseblocks, but attempts to use available284 * eraseblocks (if any). The accepted range is 0-768. If 0 is given, the285 * 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 module288 * param 'fm_autoconvert' is set, and existed old fastmap will be destroyed289 * 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 at305 * open time. Only valid for static volumes and306 * should only be used if the volume user has a307 * way to verify data integrity308 */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 in317 * volume creation requests.318 * @vol_id: volume number319 * @alignment: volume alignment320 * @bytes: volume size in bytes321 * @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 length324 * @padding2: reserved for future, not used, has to be zeroed325 * @name: volume name326 *327 * This structure is used by user-space programs when creating new volumes. The328 * @used_bytes field is only necessary when creating static volumes.329 *330 * The @alignment field specifies the required alignment of the volume logical331 * eraseblock. This means, that the size of logical eraseblocks will be aligned332 * 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 slightly336 * shortened in order to make it properly aligned. The alignment has to be337 * multiple of the flash minimal input/output unit, or %1 to utilize the entire338 * available space of logical eraseblocks.339 *340 * The @alignment field may be useful, for example, when one wants to maintain341 * a block device on top of an UBI volume. In this case, it is desirable to fit342 * an integer number of blocks in logical eraseblocks of this UBI volume. With343 * alignment it is possible to update this volume using plane UBI volume image344 * 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-size360 * @bytes: new size of the volume in bytes361 *362 * Re-sizing is possible for both dynamic and static volumes. But while dynamic363 * volumes may be re-sized arbitrarily, static volumes cannot be made to be364 * smaller than the number of bytes they bear. To arbitrarily shrink a static365 * volume, it must be wiped out first (by means of volume update operation with366 * 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-name376 * @padding1: reserved for future, not used, has to be zeroed377 * @vol_id: ID of the volume to re-name378 * @name_len: name length379 * @padding2: reserved for future, not used, has to be zeroed380 * @name: new volume name381 *382 * UBI allows to re-name up to %32 volumes at one go. The count of volumes to383 * re-name is specified in the @count field. The ID of the volumes to re-name384 * 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 cut387 * happen, the volumes will have either old name or new name. So the possible388 * use-cases of this command is atomic upgrade. Indeed, to upgrade, say, volumes389 * 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 will391 * be removed.392 *393 * If it is not desirable to remove old A and B, the re-name request has to394 * contain 4 entries: A1->A, A->A1, B1->B, B->B1, in which case old A1 and B1395 * 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 A1398 * 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, the401 * existing volume is removed, unless it is re-named as well at the same402 * 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 change417 * requests.418 * @lnum: logical eraseblock number to change419 * @bytes: how many bytes will be written to the logical eraseblock420 * @dtype: pass "3" for better compatibility with old kernels421 * @padding: reserved for future, not used, has to be zeroed422 *423 * The @dtype field used to inform UBI about what kind of data will be written424 * 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 a426 * PEB with higher erase counter for long term data. But this was not really427 * used because users usually do not know this and could easily mislead UBI. We428 * removed this feature in May 2012. UBI currently just ignores the @dtype429 * field. But for better compatibility with older kernels it is recommended to430 * 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 kernels442 * @lnum: logical eraseblock number to unmap443 * @padding: reserved for future, not used, has to be zeroed444 */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 volume454 * property.455 * @property: property to set (%UBI_VOL_PROP_DIRECT_WRITE)456 * @padding: reserved for future, not used, has to be zeroed457 * @value: value to set458 */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 zeroed468 */469struct ubi_blkcreate_req {470 __s8 padding[128];471} __packed;472 473#endif /* __UBI_USER_H__ */474