Documentation/ABI/stable/sysfs-class-ubi

   1 What:           /sys/class/ubi/
   2 Date:           July 2006
   3 KernelVersion:  2.6.22
   4 Contact:        Artem Bityutskiy <dedekind@infradead.org>
   5 Description:
   6                 The ubi/ class sub-directory belongs to the UBI subsystem and
   7                 provides general UBI information, per-UBI device information
   8                 and per-UBI volume information.
   9
  10 What:           /sys/class/ubi/version
  11 Date:           July 2006
  12 KernelVersion:  2.6.22
  13 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  14 Description:
  15                 This file contains version of the latest supported UBI on-media
  16                 format. Currently it is 1, and there is no plan to change this.
  17                 However, if in the future UBI needs on-flash format changes
  18                 which cannot be done in a compatible manner, a new format
  19                 version will be added. So this is a mechanism for possible
  20                 future backward-compatible (but forward-incompatible)
  21                 improvements.
  22
  23 What:           /sys/class/ubiX/
  24 Date:           July 2006
  25 KernelVersion:  2.6.22
  26 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  27 Description:
  28                 The /sys/class/ubi0, /sys/class/ubi1, etc directories describe
  29                 UBI devices (UBI device 0, 1, etc). They contain general UBI
  30                 device information and per UBI volume information (each UBI
  31                 device may have many UBI volumes)
  32
  33 What:           /sys/class/ubi/ubiX/avail_eraseblocks
  34 Date:           July 2006
  35 KernelVersion:  2.6.22
  36 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  37 Description:
  38                 Amount of available logical eraseblock. For example, one may
  39                 create a new UBI volume which has this amount of logical
  40                 eraseblocks.
  41
  42 What:           /sys/class/ubi/ubiX/bad_peb_count
  43 Date:           July 2006
  44 KernelVersion:  2.6.22
  45 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  46 Description:
  47                 Count of bad physical eraseblocks on the underlying MTD device.
  48
  49 What:           /sys/class/ubi/ubiX/bgt_enabled
  50 Date:           July 2006
  51 KernelVersion:  2.6.22
  52 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  53 Description:
  54                 Contains ASCII "0\n" if the UBI background thread is disabled,
  55                 and ASCII "1\n" if it is enabled.
  56
  57 What:           /sys/class/ubi/ubiX/dev
  58 Date:           July 2006
  59 KernelVersion:  2.6.22
  60 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  61 Description:
  62                 Major and minor numbers of the character device corresponding
  63                 to this UBI device (in <major>:<minor> format).
  64
  65 What:           /sys/class/ubi/ubiX/eraseblock_size
  66 Date:           July 2006
  67 KernelVersion:  2.6.22
  68 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  69 Description:
  70                 Maximum logical eraseblock size this UBI device may provide. UBI
  71                 volumes may have smaller logical eraseblock size because of their
  72                 alignment.
  73
  74 What:           /sys/class/ubi/ubiX/max_ec
  75 Date:           July 2006
  76 KernelVersion:  2.6.22
  77 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  78 Description:
  79                 Maximum physical eraseblock erase counter value.
  80
  81 What:           /sys/class/ubi/ubiX/max_vol_count
  82 Date:           July 2006
  83 KernelVersion:  2.6.22
  84 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  85 Description:
  86                 Maximum number of volumes which this UBI device may have.
  87
  88 What:           /sys/class/ubi/ubiX/min_io_size
  89 Date:           July 2006
  90 KernelVersion:  2.6.22
  91 Contact:        Artem Bityutskiy <dedekind@infradead.org>
  92 Description:
  93                 Minimum input/output unit size. All the I/O may only be done
  94                 in fractions of the contained number.
  95
  96 What:           /sys/class/ubi/ubiX/mtd_num
  97 Date:           January 2008
  98 KernelVersion:  2.6.25
  99 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 100 Description:
 101                 Number of the underlying MTD device.
 102
 103 What:           /sys/class/ubi/ubiX/reserved_for_bad
 104 Date:           July 2006
 105 KernelVersion:  2.6.22
 106 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 107 Description:
 108                 Number of physical eraseblocks reserved for bad block handling.
 109
 110 What:           /sys/class/ubi/ubiX/ro_mode
 111 Date:           April 2016
 112 KernelVersion:  4.7
 113 Contact:        linux-mtd@lists.infradead.org
 114 Description:
 115                 Contains ASCII "1\n" if the read-only flag is set on this
 116                 device, and "0\n" if it is cleared. UBI devices mark themselves
 117                 as read-only when they detect an unrecoverable error.
 118
 119 What:           /sys/class/ubi/ubiX/total_eraseblocks
 120 Date:           July 2006
 121 KernelVersion:  2.6.22
 122 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 123 Description:
 124                 Total number of good (not marked as bad) physical eraseblocks on
 125                 the underlying MTD device.
 126
 127 What:           /sys/class/ubi/ubiX/volumes_count
 128 Date:           July 2006
 129 KernelVersion:  2.6.22
 130 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 131 Description:
 132                 Count of volumes on this UBI device.
 133
 134 What:           /sys/class/ubi/ubiX/ubiX_Y/
 135 Date:           July 2006
 136 KernelVersion:  2.6.22
 137 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 138 Description:
 139                 The /sys/class/ubi/ubiX/ubiX_0/, /sys/class/ubi/ubiX/ubiX_1/,
 140                 etc directories describe UBI volumes on UBI device X (volumes
 141                 0, 1, etc).
 142
 143 What:           /sys/class/ubi/ubiX/ubiX_Y/alignment
 144 Date:           July 2006
 145 KernelVersion:  2.6.22
 146 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 147 Description:
 148                 Volume alignment - the value the logical eraseblock size of
 149                 this volume has to be aligned on. For example, 2048 means that
 150                 logical eraseblock size is multiple of 2048. In other words,
 151                 volume logical eraseblock size is UBI device logical eraseblock
 152                 size aligned to the alignment value.
 153
 154 What:           /sys/class/ubi/ubiX/ubiX_Y/corrupted
 155 Date:           July 2006
 156 KernelVersion:  2.6.22
 157 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 158 Description:
 159                 Contains ASCII "0\n" if the UBI volume is OK, and ASCII "1\n"
 160                 if it is corrupted (e.g., due to an interrupted volume update).
 161
 162 What:           /sys/class/ubi/ubiX/ubiX_Y/data_bytes
 163 Date:           July 2006
 164 KernelVersion:  2.6.22
 165 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 166 Description:
 167                 The amount of data this volume contains. This value makes sense
 168                 only for static volumes, and for dynamic volume it equivalent
 169                 to the total volume size in bytes.
 170
 171 What:           /sys/class/ubi/ubiX/ubiX_Y/dev
 172 Date:           July 2006
 173 KernelVersion:  2.6.22
 174 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 175 Description:
 176                 Major and minor numbers of the character device corresponding
 177                 to this UBI volume (in <major>:<minor> format).
 178
 179 What:           /sys/class/ubi/ubiX/ubiX_Y/name
 180 Date:           July 2006
 181 KernelVersion:  2.6.22
 182 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 183 Description:
 184                 Volume name.
 185
 186 What:           /sys/class/ubi/ubiX/ubiX_Y/reserved_ebs
 187 Date:           July 2006
 188 KernelVersion:  2.6.22
 189 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 190 Description:
 191                 Count of physical eraseblock reserved for this volume.
 192                 Equivalent to the volume size in logical eraseblocks.
 193
 194 What:           /sys/class/ubi/ubiX/ubiX_Y/type
 195 Date:           July 2006
 196 KernelVersion:  2.6.22
 197 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 198 Description:
 199                 Volume type. Contains ASCII "dynamic\n" for dynamic volumes and
 200                 "static\n" for static volumes.
 201
 202 What:           /sys/class/ubi/ubiX/ubiX_Y/upd_marker
 203 Date:           July 2006
 204 KernelVersion:  2.6.22
 205 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 206 Description:
 207                 Contains ASCII "0\n" if the update marker is not set for this
 208                 volume, and "1\n" if it is set. The update marker is set when
 209                 volume update starts, and cleaned when it ends. So the presence
 210                 of the update marker indicates that the volume is being updated
 211                 at the moment of the update was interrupted. The later may be
 212                 checked using the "corrupted" sysfs file.
 213
 214 What:           /sys/class/ubi/ubiX/ubiX_Y/usable_eb_size
 215 Date:           July 2006
 216 KernelVersion:  2.6.22
 217 Contact:        Artem Bityutskiy <dedekind@infradead.org>
 218 Description:
 219                 Logical eraseblock size of this volume. Equivalent to logical
 220                 eraseblock size of the device aligned on the volume alignment
 221                 value.