1 | /* SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) */ |
2 | /* |
3 | * Copyright (C) International Business Machines Corp., 2006 |
4 | * Authors: Artem Bityutskiy (Битюцкий Артём) |
5 | * Thomas Gleixner |
6 | * Frank Haverkamp |
7 | * Oliver Lohmann |
8 | * Andreas Arnez |
9 | * |
10 | * This file defines the layout of UBI headers and all the other UBI on-flash |
11 | * data structures. |
12 | */ |
13 | |
14 | #ifndef __UBI_MEDIA_H__ |
15 | #define __UBI_MEDIA_H__ |
16 | |
17 | #include <asm/byteorder.h> |
18 | |
19 | /* The version of UBI images supported by this implementation */ |
20 | #define UBI_VERSION 1 |
21 | |
22 | /* The highest erase counter value supported by this implementation */ |
23 | #define UBI_MAX_ERASECOUNTER 0x7FFFFFFF |
24 | |
25 | /* The initial CRC32 value used when calculating CRC checksums */ |
26 | #define UBI_CRC32_INIT 0xFFFFFFFFU |
27 | |
28 | /* Erase counter header magic number (ASCII "UBI#") */ |
29 | #define UBI_EC_HDR_MAGIC 0x55424923 |
30 | /* Volume identifier header magic number (ASCII "UBI!") */ |
31 | #define UBI_VID_HDR_MAGIC 0x55424921 |
32 | |
33 | /* |
34 | * Volume type constants used in the volume identifier header. |
35 | * |
36 | * @UBI_VID_DYNAMIC: dynamic volume |
37 | * @UBI_VID_STATIC: static volume |
38 | */ |
39 | enum { |
40 | UBI_VID_DYNAMIC = 1, |
41 | UBI_VID_STATIC = 2 |
42 | }; |
43 | |
44 | /* |
45 | * Volume flags used in the volume table record. |
46 | * |
47 | * @UBI_VTBL_AUTORESIZE_FLG: auto-resize this volume |
48 | * @UBI_VTBL_SKIP_CRC_CHECK_FLG: skip the CRC check done on a static volume at |
49 | * open time. Should only be set on volumes that |
50 | * are used by upper layers doing this kind of |
51 | * check. Main use-case for this flag is |
52 | * boot-time reduction |
53 | * |
54 | * %UBI_VTBL_AUTORESIZE_FLG flag can be set only for one volume in the volume |
55 | * table. UBI automatically re-sizes the volume which has this flag and makes |
56 | * the volume to be of largest possible size. This means that if after the |
57 | * initialization UBI finds out that there are available physical eraseblocks |
58 | * present on the device, it automatically appends all of them to the volume |
59 | * (the physical eraseblocks reserved for bad eraseblocks handling and other |
60 | * reserved physical eraseblocks are not taken). So, if there is a volume with |
61 | * the %UBI_VTBL_AUTORESIZE_FLG flag set, the amount of available logical |
62 | * eraseblocks will be zero after UBI is loaded, because all of them will be |
63 | * reserved for this volume. Note, the %UBI_VTBL_AUTORESIZE_FLG bit is cleared |
64 | * after the volume had been initialized. |
65 | * |
66 | * The auto-resize feature is useful for device production purposes. For |
67 | * example, different NAND flash chips may have different amount of initial bad |
68 | * eraseblocks, depending of particular chip instance. Manufacturers of NAND |
69 | * chips usually guarantee that the amount of initial bad eraseblocks does not |
70 | * exceed certain percent, e.g. 2%. When one creates an UBI image which will be |
71 | * flashed to the end devices in production, he does not know the exact amount |
72 | * of good physical eraseblocks the NAND chip on the device will have, but this |
73 | * number is required to calculate the volume sized and put them to the volume |
74 | * table of the UBI image. In this case, one of the volumes (e.g., the one |
75 | * which will store the root file system) is marked as "auto-resizable", and |
76 | * UBI will adjust its size on the first boot if needed. |
77 | * |
78 | * Note, first UBI reserves some amount of physical eraseblocks for bad |
79 | * eraseblock handling, and then re-sizes the volume, not vice-versa. This |
80 | * means that the pool of reserved physical eraseblocks will always be present. |
81 | */ |
82 | enum { |
83 | UBI_VTBL_AUTORESIZE_FLG = 0x01, |
84 | UBI_VTBL_SKIP_CRC_CHECK_FLG = 0x02, |
85 | }; |
86 | |
87 | /* |
88 | * Compatibility constants used by internal volumes. |
89 | * |
90 | * @UBI_COMPAT_DELETE: delete this internal volume before anything is written |
91 | * to the flash |
92 | * @UBI_COMPAT_RO: attach this device in read-only mode |
93 | * @UBI_COMPAT_PRESERVE: preserve this internal volume - do not touch its |
94 | * physical eraseblocks, don't allow the wear-leveling |
95 | * sub-system to move them |
96 | * @UBI_COMPAT_REJECT: reject this UBI image |
97 | */ |
98 | enum { |
99 | UBI_COMPAT_DELETE = 1, |
100 | UBI_COMPAT_RO = 2, |
101 | UBI_COMPAT_PRESERVE = 4, |
102 | UBI_COMPAT_REJECT = 5 |
103 | }; |
104 | |
105 | /* Sizes of UBI headers */ |
106 | #define UBI_EC_HDR_SIZE sizeof(struct ubi_ec_hdr) |
107 | #define UBI_VID_HDR_SIZE sizeof(struct ubi_vid_hdr) |
108 | |
109 | /* Sizes of UBI headers without the ending CRC */ |
110 | #define UBI_EC_HDR_SIZE_CRC (UBI_EC_HDR_SIZE - sizeof(__be32)) |
111 | #define UBI_VID_HDR_SIZE_CRC (UBI_VID_HDR_SIZE - sizeof(__be32)) |
112 | |
113 | /** |
114 | * struct ubi_ec_hdr - UBI erase counter header. |
115 | * @magic: erase counter header magic number (%UBI_EC_HDR_MAGIC) |
116 | * @version: version of UBI implementation which is supposed to accept this |
117 | * UBI image |
118 | * @padding1: reserved for future, zeroes |
119 | * @ec: the erase counter |
120 | * @vid_hdr_offset: where the VID header starts |
121 | * @data_offset: where the user data start |
122 | * @image_seq: image sequence number |
123 | * @padding2: reserved for future, zeroes |
124 | * @hdr_crc: erase counter header CRC checksum |
125 | * |
126 | * The erase counter header takes 64 bytes and has a plenty of unused space for |
127 | * future usage. The unused fields are zeroed. The @version field is used to |
128 | * indicate the version of UBI implementation which is supposed to be able to |
129 | * work with this UBI image. If @version is greater than the current UBI |
130 | * version, the image is rejected. This may be useful in future if something |
131 | * is changed radically. This field is duplicated in the volume identifier |
132 | * header. |
133 | * |
134 | * The @vid_hdr_offset and @data_offset fields contain the offset of the |
135 | * volume identifier header and user data, relative to the beginning of the |
136 | * physical eraseblock. These values have to be the same for all physical |
137 | * eraseblocks. |
138 | * |
139 | * The @image_seq field is used to validate a UBI image that has been prepared |
140 | * for a UBI device. The @image_seq value can be any value, but it must be the |
141 | * same on all eraseblocks. UBI will ensure that all new erase counter headers |
142 | * also contain this value, and will check the value when attaching the flash. |
143 | * One way to make use of @image_seq is to increase its value by one every time |
144 | * an image is flashed over an existing image, then, if the flashing does not |
145 | * complete, UBI will detect the error when attaching the media. |
146 | */ |
147 | struct ubi_ec_hdr { |
148 | __be32 magic; |
149 | __u8 version; |
150 | __u8 padding1[3]; |
151 | __be64 ec; /* Warning: the current limit is 31-bit anyway! */ |
152 | __be32 vid_hdr_offset; |
153 | __be32 data_offset; |
154 | __be32 image_seq; |
155 | __u8 padding2[32]; |
156 | __be32 hdr_crc; |
157 | } __packed; |
158 | |
159 | /** |
160 | * struct ubi_vid_hdr - on-flash UBI volume identifier header. |
161 | * @magic: volume identifier header magic number (%UBI_VID_HDR_MAGIC) |
162 | * @version: UBI implementation version which is supposed to accept this UBI |
163 | * image (%UBI_VERSION) |
164 | * @vol_type: volume type (%UBI_VID_DYNAMIC or %UBI_VID_STATIC) |
165 | * @copy_flag: if this logical eraseblock was copied from another physical |
166 | * eraseblock (for wear-leveling reasons) |
167 | * @compat: compatibility of this volume (%0, %UBI_COMPAT_DELETE, |
168 | * %UBI_COMPAT_IGNORE, %UBI_COMPAT_PRESERVE, or %UBI_COMPAT_REJECT) |
169 | * @vol_id: ID of this volume |
170 | * @lnum: logical eraseblock number |
171 | * @padding1: reserved for future, zeroes |
172 | * @data_size: how many bytes of data this logical eraseblock contains |
173 | * @used_ebs: total number of used logical eraseblocks in this volume |
174 | * @data_pad: how many bytes at the end of this physical eraseblock are not |
175 | * used |
176 | * @data_crc: CRC checksum of the data stored in this logical eraseblock |
177 | * @padding2: reserved for future, zeroes |
178 | * @sqnum: sequence number |
179 | * @padding3: reserved for future, zeroes |
180 | * @hdr_crc: volume identifier header CRC checksum |
181 | * |
182 | * The @sqnum is the value of the global sequence counter at the time when this |
183 | * VID header was created. The global sequence counter is incremented each time |
184 | * UBI writes a new VID header to the flash, i.e. when it maps a logical |
185 | * eraseblock to a new physical eraseblock. The global sequence counter is an |
186 | * unsigned 64-bit integer and we assume it never overflows. The @sqnum |
187 | * (sequence number) is used to distinguish between older and newer versions of |
188 | * logical eraseblocks. |
189 | * |
190 | * There are 2 situations when there may be more than one physical eraseblock |
191 | * corresponding to the same logical eraseblock, i.e., having the same @vol_id |
192 | * and @lnum values in the volume identifier header. Suppose we have a logical |
193 | * eraseblock L and it is mapped to the physical eraseblock P. |
194 | * |
195 | * 1. Because UBI may erase physical eraseblocks asynchronously, the following |
196 | * situation is possible: L is asynchronously erased, so P is scheduled for |
197 | * erasure, then L is written to,i.e. mapped to another physical eraseblock P1, |
198 | * so P1 is written to, then an unclean reboot happens. Result - there are 2 |
199 | * physical eraseblocks P and P1 corresponding to the same logical eraseblock |
200 | * L. But P1 has greater sequence number, so UBI picks P1 when it attaches the |
201 | * flash. |
202 | * |
203 | * 2. From time to time UBI moves logical eraseblocks to other physical |
204 | * eraseblocks for wear-leveling reasons. If, for example, UBI moves L from P |
205 | * to P1, and an unclean reboot happens before P is physically erased, there |
206 | * are two physical eraseblocks P and P1 corresponding to L and UBI has to |
207 | * select one of them when the flash is attached. The @sqnum field says which |
208 | * PEB is the original (obviously P will have lower @sqnum) and the copy. But |
209 | * it is not enough to select the physical eraseblock with the higher sequence |
210 | * number, because the unclean reboot could have happen in the middle of the |
211 | * copying process, so the data in P is corrupted. It is also not enough to |
212 | * just select the physical eraseblock with lower sequence number, because the |
213 | * data there may be old (consider a case if more data was added to P1 after |
214 | * the copying). Moreover, the unclean reboot may happen when the erasure of P |
215 | * was just started, so it result in unstable P, which is "mostly" OK, but |
216 | * still has unstable bits. |
217 | * |
218 | * UBI uses the @copy_flag field to indicate that this logical eraseblock is a |
219 | * copy. UBI also calculates data CRC when the data is moved and stores it at |
220 | * the @data_crc field of the copy (P1). So when UBI needs to pick one physical |
221 | * eraseblock of two (P or P1), the @copy_flag of the newer one (P1) is |
222 | * examined. If it is cleared, the situation is simple and the newer one is |
223 | * picked. If it is set, the data CRC of the copy (P1) is examined. If the CRC |
224 | * checksum is correct, this physical eraseblock is selected (P1). Otherwise |
225 | * the older one (P) is selected. |
226 | * |
227 | * There are 2 sorts of volumes in UBI: user volumes and internal volumes. |
228 | * Internal volumes are not seen from outside and are used for various internal |
229 | * UBI purposes. In this implementation there is only one internal volume - the |
230 | * layout volume. Internal volumes are the main mechanism of UBI extensions. |
231 | * For example, in future one may introduce a journal internal volume. Internal |
232 | * volumes have their own reserved range of IDs. |
233 | * |
234 | * The @compat field is only used for internal volumes and contains the "degree |
235 | * of their compatibility". It is always zero for user volumes. This field |
236 | * provides a mechanism to introduce UBI extensions and to be still compatible |
237 | * with older UBI binaries. For example, if someone introduced a journal in |
238 | * future, he would probably use %UBI_COMPAT_DELETE compatibility for the |
239 | * journal volume. And in this case, older UBI binaries, which know nothing |
240 | * about the journal volume, would just delete this volume and work perfectly |
241 | * fine. This is similar to what Ext2fs does when it is fed by an Ext3fs image |
242 | * - it just ignores the Ext3fs journal. |
243 | * |
244 | * The @data_crc field contains the CRC checksum of the contents of the logical |
245 | * eraseblock if this is a static volume. In case of dynamic volumes, it does |
246 | * not contain the CRC checksum as a rule. The only exception is when the |
247 | * data of the physical eraseblock was moved by the wear-leveling sub-system, |
248 | * then the wear-leveling sub-system calculates the data CRC and stores it in |
249 | * the @data_crc field. And of course, the @copy_flag is %in this case. |
250 | * |
251 | * The @data_size field is used only for static volumes because UBI has to know |
252 | * how many bytes of data are stored in this eraseblock. For dynamic volumes, |
253 | * this field usually contains zero. The only exception is when the data of the |
254 | * physical eraseblock was moved to another physical eraseblock for |
255 | * wear-leveling reasons. In this case, UBI calculates CRC checksum of the |
256 | * contents and uses both @data_crc and @data_size fields. In this case, the |
257 | * @data_size field contains data size. |
258 | * |
259 | * The @used_ebs field is used only for static volumes and indicates how many |
260 | * eraseblocks the data of the volume takes. For dynamic volumes this field is |
261 | * not used and always contains zero. |
262 | * |
263 | * The @data_pad is calculated when volumes are created using the alignment |
264 | * parameter. So, effectively, the @data_pad field reduces the size of logical |
265 | * eraseblocks of this volume. This is very handy when one uses block-oriented |
266 | * software (say, cramfs) on top of the UBI volume. |
267 | */ |
268 | struct ubi_vid_hdr { |
269 | __be32 magic; |
270 | __u8 version; |
271 | __u8 vol_type; |
272 | __u8 copy_flag; |
273 | __u8 compat; |
274 | __be32 vol_id; |
275 | __be32 lnum; |
276 | __u8 padding1[4]; |
277 | __be32 data_size; |
278 | __be32 used_ebs; |
279 | __be32 data_pad; |
280 | __be32 data_crc; |
281 | __u8 padding2[4]; |
282 | __be64 sqnum; |
283 | __u8 padding3[12]; |
284 | __be32 hdr_crc; |
285 | } __packed; |
286 | |
287 | /* Internal UBI volumes count */ |
288 | #define UBI_INT_VOL_COUNT 1 |
289 | |
290 | /* |
291 | * Starting ID of internal volumes: 0x7fffefff. |
292 | * There is reserved room for 4096 internal volumes. |
293 | */ |
294 | #define UBI_INTERNAL_VOL_START (0x7FFFFFFF - 4096) |
295 | |
296 | /* The layout volume contains the volume table */ |
297 | |
298 | #define UBI_LAYOUT_VOLUME_ID UBI_INTERNAL_VOL_START |
299 | #define UBI_LAYOUT_VOLUME_TYPE UBI_VID_DYNAMIC |
300 | #define UBI_LAYOUT_VOLUME_ALIGN 1 |
301 | #define UBI_LAYOUT_VOLUME_EBS 2 |
302 | #define UBI_LAYOUT_VOLUME_NAME "layout volume" |
303 | #define UBI_LAYOUT_VOLUME_COMPAT UBI_COMPAT_REJECT |
304 | |
305 | /* The maximum number of volumes per one UBI device */ |
306 | #define UBI_MAX_VOLUMES 128 |
307 | |
308 | /* The maximum volume name length */ |
309 | #define UBI_VOL_NAME_MAX 127 |
310 | |
311 | /* Size of the volume table record */ |
312 | #define UBI_VTBL_RECORD_SIZE sizeof(struct ubi_vtbl_record) |
313 | |
314 | /* Size of the volume table record without the ending CRC */ |
315 | #define UBI_VTBL_RECORD_SIZE_CRC (UBI_VTBL_RECORD_SIZE - sizeof(__be32)) |
316 | |
317 | /** |
318 | * struct ubi_vtbl_record - a record in the volume table. |
319 | * @reserved_pebs: how many physical eraseblocks are reserved for this volume |
320 | * @alignment: volume alignment |
321 | * @data_pad: how many bytes are unused at the end of the each physical |
322 | * eraseblock to satisfy the requested alignment |
323 | * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME) |
324 | * @upd_marker: if volume update was started but not finished |
325 | * @name_len: volume name length |
326 | * @name: the volume name |
327 | * @flags: volume flags (%UBI_VTBL_AUTORESIZE_FLG) |
328 | * @padding: reserved, zeroes |
329 | * @crc: a CRC32 checksum of the record |
330 | * |
331 | * The volume table records are stored in the volume table, which is stored in |
332 | * the layout volume. The layout volume consists of 2 logical eraseblock, each |
333 | * of which contains a copy of the volume table (i.e., the volume table is |
334 | * duplicated). The volume table is an array of &struct ubi_vtbl_record |
335 | * objects indexed by the volume ID. |
336 | * |
337 | * If the size of the logical eraseblock is large enough to fit |
338 | * %UBI_MAX_VOLUMES records, the volume table contains %UBI_MAX_VOLUMES |
339 | * records. Otherwise, it contains as many records as it can fit (i.e., size of |
340 | * logical eraseblock divided by sizeof(struct ubi_vtbl_record)). |
341 | * |
342 | * The @upd_marker flag is used to implement volume update. It is set to %1 |
343 | * before update and set to %0 after the update. So if the update operation was |
344 | * interrupted, UBI knows that the volume is corrupted. |
345 | * |
346 | * The @alignment field is specified when the volume is created and cannot be |
347 | * later changed. It may be useful, for example, when a block-oriented file |
348 | * system works on top of UBI. The @data_pad field is calculated using the |
349 | * logical eraseblock size and @alignment. The alignment must be multiple to the |
350 | * minimal flash I/O unit. If @alignment is 1, all the available space of |
351 | * the physical eraseblocks is used. |
352 | * |
353 | * Empty records contain all zeroes and the CRC checksum of those zeroes. |
354 | */ |
355 | struct ubi_vtbl_record { |
356 | __be32 reserved_pebs; |
357 | __be32 alignment; |
358 | __be32 data_pad; |
359 | __u8 vol_type; |
360 | __u8 upd_marker; |
361 | __be16 name_len; |
362 | __u8 name[UBI_VOL_NAME_MAX+1]; |
363 | __u8 flags; |
364 | __u8 padding[23]; |
365 | __be32 crc; |
366 | } __packed; |
367 | |
368 | /* UBI fastmap on-flash data structures */ |
369 | |
370 | #define UBI_FM_SB_VOLUME_ID (UBI_LAYOUT_VOLUME_ID + 1) |
371 | #define UBI_FM_DATA_VOLUME_ID (UBI_LAYOUT_VOLUME_ID + 2) |
372 | |
373 | /* fastmap on-flash data structure format version */ |
374 | #define UBI_FM_FMT_VERSION 1 |
375 | |
376 | #define UBI_FM_SB_MAGIC 0x7B11D69F |
377 | #define UBI_FM_HDR_MAGIC 0xD4B82EF7 |
378 | #define UBI_FM_VHDR_MAGIC 0xFA370ED1 |
379 | #define UBI_FM_POOL_MAGIC 0x67AF4D08 |
380 | #define UBI_FM_EBA_MAGIC 0xf0c040a8 |
381 | |
382 | /* A fastmap super block can be located between PEB 0 and |
383 | * UBI_FM_MAX_START */ |
384 | #define UBI_FM_MAX_START 64 |
385 | |
386 | /* A fastmap can use up to UBI_FM_MAX_BLOCKS PEBs */ |
387 | #define UBI_FM_MAX_BLOCKS 32 |
388 | |
389 | /* 5% of the total number of PEBs have to be scanned while attaching |
390 | * from a fastmap. |
391 | * But the size of this pool is limited to be between UBI_FM_MIN_POOL_SIZE and |
392 | * UBI_FM_MAX_POOL_SIZE */ |
393 | #define UBI_FM_MIN_POOL_SIZE 8 |
394 | #define UBI_FM_MAX_POOL_SIZE 256 |
395 | |
396 | /** |
397 | * struct ubi_fm_sb - UBI fastmap super block |
398 | * @magic: fastmap super block magic number (%UBI_FM_SB_MAGIC) |
399 | * @version: format version of this fastmap |
400 | * @data_crc: CRC over the fastmap data |
401 | * @used_blocks: number of PEBs used by this fastmap |
402 | * @block_loc: an array containing the location of all PEBs of the fastmap |
403 | * @block_ec: the erase counter of each used PEB |
404 | * @sqnum: highest sequence number value at the time while taking the fastmap |
405 | * |
406 | */ |
407 | struct ubi_fm_sb { |
408 | __be32 magic; |
409 | __u8 version; |
410 | __u8 padding1[3]; |
411 | __be32 data_crc; |
412 | __be32 used_blocks; |
413 | __be32 block_loc[UBI_FM_MAX_BLOCKS]; |
414 | __be32 block_ec[UBI_FM_MAX_BLOCKS]; |
415 | __be64 sqnum; |
416 | __u8 padding2[32]; |
417 | } __packed; |
418 | |
419 | /** |
420 | * struct ubi_fm_hdr - header of the fastmap data set |
421 | * @magic: fastmap header magic number (%UBI_FM_HDR_MAGIC) |
422 | * @free_peb_count: number of free PEBs known by this fastmap |
423 | * @used_peb_count: number of used PEBs known by this fastmap |
424 | * @scrub_peb_count: number of to be scrubbed PEBs known by this fastmap |
425 | * @bad_peb_count: number of bad PEBs known by this fastmap |
426 | * @erase_peb_count: number of bad PEBs which have to be erased |
427 | * @vol_count: number of UBI volumes known by this fastmap |
428 | */ |
429 | struct ubi_fm_hdr { |
430 | __be32 magic; |
431 | __be32 free_peb_count; |
432 | __be32 used_peb_count; |
433 | __be32 scrub_peb_count; |
434 | __be32 bad_peb_count; |
435 | __be32 erase_peb_count; |
436 | __be32 vol_count; |
437 | __u8 padding[4]; |
438 | } __packed; |
439 | |
440 | /* struct ubi_fm_hdr is followed by two struct ubi_fm_scan_pool */ |
441 | |
442 | /** |
443 | * struct ubi_fm_scan_pool - Fastmap pool PEBs to be scanned while attaching |
444 | * @magic: pool magic numer (%UBI_FM_POOL_MAGIC) |
445 | * @size: current pool size |
446 | * @max_size: maximal pool size |
447 | * @pebs: an array containing the location of all PEBs in this pool |
448 | */ |
449 | struct ubi_fm_scan_pool { |
450 | __be32 magic; |
451 | __be16 size; |
452 | __be16 max_size; |
453 | __be32 pebs[UBI_FM_MAX_POOL_SIZE]; |
454 | __be32 padding[4]; |
455 | } __packed; |
456 | |
457 | /* ubi_fm_scan_pool is followed by nfree+nused struct ubi_fm_ec records */ |
458 | |
459 | /** |
460 | * struct ubi_fm_ec - stores the erase counter of a PEB |
461 | * @pnum: PEB number |
462 | * @ec: ec of this PEB |
463 | */ |
464 | struct ubi_fm_ec { |
465 | __be32 pnum; |
466 | __be32 ec; |
467 | } __packed; |
468 | |
469 | /** |
470 | * struct ubi_fm_volhdr - Fastmap volume header |
471 | * it identifies the start of an eba table |
472 | * @magic: Fastmap volume header magic number (%UBI_FM_VHDR_MAGIC) |
473 | * @vol_id: volume id of the fastmapped volume |
474 | * @vol_type: type of the fastmapped volume |
475 | * @data_pad: data_pad value of the fastmapped volume |
476 | * @used_ebs: number of used LEBs within this volume |
477 | * @last_eb_bytes: number of bytes used in the last LEB |
478 | */ |
479 | struct ubi_fm_volhdr { |
480 | __be32 magic; |
481 | __be32 vol_id; |
482 | __u8 vol_type; |
483 | __u8 padding1[3]; |
484 | __be32 data_pad; |
485 | __be32 used_ebs; |
486 | __be32 last_eb_bytes; |
487 | __u8 padding2[8]; |
488 | } __packed; |
489 | |
490 | /* struct ubi_fm_volhdr is followed by one struct ubi_fm_eba records */ |
491 | |
492 | /** |
493 | * struct ubi_fm_eba - denotes an association between a PEB and LEB |
494 | * @magic: EBA table magic number |
495 | * @reserved_pebs: number of table entries |
496 | * @pnum: PEB number of LEB (LEB is the index) |
497 | */ |
498 | struct ubi_fm_eba { |
499 | __be32 magic; |
500 | __be32 reserved_pebs; |
501 | __be32 pnum[]; |
502 | } __packed; |
503 | #endif /* !__UBI_MEDIA_H__ */ |
504 | |