What: /sys/class/ubi/ Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: The ubi/ class sub-directory belongs to the UBI subsystem and provides general UBI information, per-UBI device information and per-UBI volume information. What: /sys/class/ubi/version Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: This file contains version of the latest supported UBI on-media format. Currently it is 1, and there is no plan to change this. However, if in the future UBI needs on-flash format changes which cannot be done in a compatible manner, a new format version will be added. So this is a mechanism for possible future backward-compatible (but forward-incompatible) improvements. What: /sys/class/ubiX/ Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: The /sys/class/ubi0, /sys/class/ubi1, etc directories describe UBI devices (UBI device 0, 1, etc). They contain general UBI device information and per UBI volume information (each UBI device may have many UBI volumes) What: /sys/class/ubi/ubiX/avail_eraseblocks Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Amount of available logical eraseblock. For example, one may create a new UBI volume which has this amount of logical eraseblocks. What: /sys/class/ubi/ubiX/bad_peb_count Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Count of bad physical eraseblocks on the underlying MTD device. What: /sys/class/ubi/ubiX/bgt_enabled Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Contains ASCII "0\n" if the UBI background thread is disabled, and ASCII "1\n" if it is enabled. What: /sys/class/ubi/ubiX/dev Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Major and minor numbers of the character device corresponding to this UBI device (in : format). What: /sys/class/ubi/ubiX/eraseblock_size Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Maximum logical eraseblock size this UBI device may provide. UBI volumes may have smaller logical eraseblock size because of their alignment. What: /sys/class/ubi/ubiX/max_ec Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Maximum physical eraseblock erase counter value. What: /sys/class/ubi/ubiX/max_vol_count Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Maximum number of volumes which this UBI device may have. What: /sys/class/ubi/ubiX/min_io_size Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Minimum input/output unit size. All the I/O may only be done in fractions of the contained number. What: /sys/class/ubi/ubiX/mtd_num Date: January 2008 KernelVersion: 2.6.25 Contact: Artem Bityutskiy Description: Number of the underlying MTD device. What: /sys/class/ubi/ubiX/reserved_for_bad Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Number of physical eraseblocks reserved for bad block handling. What: /sys/class/ubi/ubiX/ro_mode Date: April 2016 KernelVersion: 4.7 Contact: linux-mtd@lists.infradead.org Description: Contains ASCII "1\n" if the read-only flag is set on this device, and "0\n" if it is cleared. UBI devices mark themselves as read-only when they detect an unrecoverable error. What: /sys/class/ubi/ubiX/total_eraseblocks Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Total number of good (not marked as bad) physical eraseblocks on the underlying MTD device. What: /sys/class/ubi/ubiX/volumes_count Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Count of volumes on this UBI device. What: /sys/class/ubi/ubiX/ubiX_Y/ Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: The /sys/class/ubi/ubiX/ubiX_0/, /sys/class/ubi/ubiX/ubiX_1/, etc directories describe UBI volumes on UBI device X (volumes 0, 1, etc). What: /sys/class/ubi/ubiX/ubiX_Y/alignment Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Volume alignment - the value the logical eraseblock size of this volume has to be aligned on. For example, 2048 means that logical eraseblock size is multiple of 2048. In other words, volume logical eraseblock size is UBI device logical eraseblock size aligned to the alignment value. What: /sys/class/ubi/ubiX/ubiX_Y/corrupted Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Contains ASCII "0\n" if the UBI volume is OK, and ASCII "1\n" if it is corrupted (e.g., due to an interrupted volume update). What: /sys/class/ubi/ubiX/ubiX_Y/data_bytes Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: The amount of data this volume contains. This value makes sense only for static volumes, and for dynamic volume it equivalent to the total volume size in bytes. What: /sys/class/ubi/ubiX/ubiX_Y/dev Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Major and minor numbers of the character device corresponding to this UBI volume (in : format). What: /sys/class/ubi/ubiX/ubiX_Y/name Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Volume name. What: /sys/class/ubi/ubiX/ubiX_Y/reserved_ebs Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Count of physical eraseblock reserved for this volume. Equivalent to the volume size in logical eraseblocks. What: /sys/class/ubi/ubiX/ubiX_Y/type Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Volume type. Contains ASCII "dynamic\n" for dynamic volumes and "static\n" for static volumes. What: /sys/class/ubi/ubiX/ubiX_Y/upd_marker Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Contains ASCII "0\n" if the update marker is not set for this volume, and "1\n" if it is set. The update marker is set when volume update starts, and cleaned when it ends. So the presence of the update marker indicates that the volume is being updated at the moment of the update was interrupted. The later may be checked using the "corrupted" sysfs file. What: /sys/class/ubi/ubiX/ubiX_Y/usable_eb_size Date: July 2006 KernelVersion: 2.6.22 Contact: Artem Bityutskiy Description: Logical eraseblock size of this volume. Equivalent to logical eraseblock size of the device aligned on the volume alignment value.