mtd/ubi/ubi-media.h

1 /* SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) */
10  * This file defines the layout of UBI headers and all the other UBI on-flash
47  * @UBI_VTBL_AUTORESIZE_FLG: auto-resize this volume
51  *				 check. Main use-case for this flag is
52  *				 boot-time reduction
55  * table. UBI automatically re-sizes the volume which has this flag and makes
66  * The auto-resize feature is useful for device production purposes. For
75  * which will store the root file system) is marked as "auto-resizable", and
79  * eraseblock handling, and then re-sizes the volume, not vice-versa. This
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
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))
114  * struct ubi_ec_hdr - UBI erase counter header.
151 	__be64  ec; /* Warning: the current limit is 31-bit anyway! */
160  * struct ubi_vid_hdr - on-flash UBI volume identifier header.
166  *             eraseblock (for wear-leveling reasons)
186  * unsigned 64-bit integer and we assume it never overflows. The @sqnum
198  * so P1 is written to, then an unclean reboot happens. Result - there are 2
204  * eraseblocks for wear-leveling reasons. If, for example, UBI moves L from P
229  * UBI purposes. In this implementation there is only one internal volume - the
242  * - it just ignores the Ext3fs journal.
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
255  * wear-leveling reasons. In this case, UBI calculates CRC checksum of the
265  * eraseblocks of this volume. This is very handy when one uses block-oriented
294 #define UBI_INTERNAL_VOL_START (0x7FFFFFFF - 4096)
315 #define UBI_VTBL_RECORD_SIZE_CRC (UBI_VTBL_RECORD_SIZE - sizeof(__be32))
318  * struct ubi_vtbl_record - a record in the volume table.
347  * later changed. It may be useful, for example, when a block-oriented file
368 /* UBI fastmap on-flash data structures */
373 /* fastmap on-flash data structure format version */
397  * struct ubi_fm_sb - UBI fastmap super block
420  * struct ubi_fm_hdr - header of the fastmap data set
443  * struct ubi_fm_scan_pool - Fastmap pool PEBs to be scanned while attaching
460  * struct ubi_fm_ec - stores the erase counter of a PEB
470  * struct ubi_fm_volhdr - Fastmap volume header
493  * struct ubi_fm_eba - denotes an association between a PEB and LEB