mtd/ubi/ubi-media.h

34 /* Volume identifier header magic number (ASCII "UBI!") */
38  * Volume type constants used in the volume identifier header.
40  * @UBI_VID_DYNAMIC: dynamic volume
41  * @UBI_VID_STATIC: static volume
49  * Volume flags used in the volume table record.
51  * @UBI_VTBL_AUTORESIZE_FLG: auto-resize this volume
53  * %UBI_VTBL_AUTORESIZE_FLG flag can be set only for one volume in the volume
54  * table. UBI automatically re-sizes the volume which has this flag and makes
55  * the volume to be of largest possible size. This means that if after the
57  * present on the device, it automatically appends all of them to the volume
59  * reserved physical eraseblocks are not taken). So, if there is a volume with
62  * reserved for this volume. Note, the %UBI_VTBL_AUTORESIZE_FLG bit is cleared
63  * after the volume had been initialized.
72  * number is required to calculate the volume sized and put them to the volume
78  * eraseblock handling, and then re-sizes the volume, not vice-versa. This
88  * @UBI_COMPAT_DELETE: delete this internal volume before anything is written
91  * @UBI_COMPAT_PRESERVE: preserve this internal volume - do not touch its
129  * is changed radically. This field is duplicated in the volume identifier
133  * volume identifier header and user data, relative to the beginning of the
158  * struct ubi_vid_hdr - on-flash UBI volume identifier header.
159  * @magic: volume identifier header magic number (%UBI_VID_HDR_MAGIC)
162  * @vol_type: volume type (%UBI_VID_DYNAMIC or %UBI_VID_STATIC)
165  * @compat: compatibility of this volume (%0, %UBI_COMPAT_DELETE,
167  * @vol_id: ID of this volume
171  * @used_ebs: total number of used logical eraseblocks in this volume
178  * @hdr_crc: volume identifier header CRC checksum
190  * and @lnum values in the volume identifier header. Suppose we have a logical
227  * UBI purposes. In this implementation there is only one internal volume - the
228  * layout volume. Internal volumes are the main mechanism of UBI extensions.
229  * For example, in future one may introduce a journal internal volume. Internal
237  * journal volume.  And in this case, older UBI binaries, which know nothing
238  * about the journal volume, would just delete this volume and work perfectly
243  * eraseblock if this is a static volume. In case of dynamic volumes, it does
258  * eraseblocks the data of the volume takes. For dynamic volumes this field is
263  * eraseblocks of this volume. This is very handy when one uses block-oriented
264  * software (say, cramfs) on top of the UBI volume.
294 /* The layout volume contains the volume table */
300 #define UBI_LAYOUT_VOLUME_NAME   "layout volume"
306 /* The maximum volume name length */
309 /* Size of the volume table record */
312 /* Size of the volume table record without the ending CRC */
316  * struct ubi_vtbl_record - a record in the volume table.
317  * @reserved_pebs: how many physical eraseblocks are reserved for this volume
318  * @alignment: volume alignment
321  * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
322  * @upd_marker: if volume update was started but not finished
323  * @name_len: volume name length
324  * @name: the volume name
325  * @flags: volume flags (%UBI_VTBL_AUTORESIZE_FLG)
329  * The volume table records are stored in the volume table, which is stored in
330  * the layout volume. The layout volume consists of 2 logical eraseblock, each
331  * of which contains a copy of the volume table (i.e., the volume table is
332  * duplicated). The volume table is an array of &struct ubi_vtbl_record
333  * objects indexed by the volume ID.
336  * %UBI_MAX_VOLUMES records, the volume table contains %UBI_MAX_VOLUMES
340  * The @upd_marker flag is used to implement volume update. It is set to %1
342  * interrupted, UBI knows that the volume is corrupted.
344  * The @alignment field is specified when the volume is created and cannot be
472  * struct ubi_fm_volhdr - Fastmap volume header
474  * @magic: Fastmap volume header magic number (%UBI_FM_VHDR_MAGIC)
475  * @vol_id: volume id of the fastmapped volume
476  * @vol_type: type of the fastmapped volume
477  * @data_pad: data_pad value of the fastmapped volume
478  * @used_ebs: number of used LEBs within this volume