1What:		/sys/class/ubi/
2Date:		July 2006
3KernelVersion:	2.6.22
4Contact:	Artem Bityutskiy <dedekind@infradead.org>
5Description:
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
10What:		/sys/class/ubi/version
11Date:		July 2006
12KernelVersion:	2.6.22
13Contact:	Artem Bityutskiy <dedekind@infradead.org>
14Description:
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
23What:		/sys/class/ubiX/
24Date:		July 2006
25KernelVersion:	2.6.22
26Contact:	Artem Bityutskiy <dedekind@infradead.org>
27Description:
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
33What:		/sys/class/ubi/ubiX/avail_eraseblocks
34Date:		July 2006
35KernelVersion:	2.6.22
36Contact:	Artem Bityutskiy <dedekind@infradead.org>
37Description:
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
42What:		/sys/class/ubi/ubiX/bad_peb_count
43Date:		July 2006
44KernelVersion:	2.6.22
45Contact:	Artem Bityutskiy <dedekind@infradead.org>
46Description:
47		Count of bad physical eraseblocks on the underlying MTD device.
48
49What:		/sys/class/ubi/ubiX/bgt_enabled
50Date:		July 2006
51KernelVersion:	2.6.22
52Contact:	Artem Bityutskiy <dedekind@infradead.org>
53Description:
54		Contains ASCII "0\n" if the UBI background thread is disabled,
55		and ASCII "1\n" if it is enabled.
56
57What:		/sys/class/ubi/ubiX/dev
58Date:		July 2006
59KernelVersion:	2.6.22
60Contact:	Artem Bityutskiy <dedekind@infradead.org>
61Description:
62		Major and minor numbers of the character device corresponding
63		to this UBI device (in <major>:<minor> format).
64
65What:		/sys/class/ubi/ubiX/eraseblock_size
66Date:		July 2006
67KernelVersion:	2.6.22
68Contact:	Artem Bityutskiy <dedekind@infradead.org>
69Description:
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
74What:		/sys/class/ubi/ubiX/max_ec
75Date:		July 2006
76KernelVersion:	2.6.22
77Contact:	Artem Bityutskiy <dedekind@infradead.org>
78Description:
79		Maximum physical eraseblock erase counter value.
80
81What:		/sys/class/ubi/ubiX/max_vol_count
82Date:		July 2006
83KernelVersion:	2.6.22
84Contact:	Artem Bityutskiy <dedekind@infradead.org>
85Description:
86		Maximum number of volumes which this UBI device may have.
87
88What:		/sys/class/ubi/ubiX/min_io_size
89Date:		July 2006
90KernelVersion:	2.6.22
91Contact:	Artem Bityutskiy <dedekind@infradead.org>
92Description:
93		Minimum input/output unit size. All the I/O may only be done
94		in fractions of the contained number.
95
96What:		/sys/class/ubi/ubiX/mtd_num
97Date:		January 2008
98KernelVersion:	2.6.25
99Contact:	Artem Bityutskiy <dedekind@infradead.org>
100Description:
101		Number of the underlying MTD device.
102
103What:		/sys/class/ubi/ubiX/reserved_for_bad
104Date:		July 2006
105KernelVersion:	2.6.22
106Contact:	Artem Bityutskiy <dedekind@infradead.org>
107Description:
108		Number of physical eraseblocks reserved for bad block handling.
109
110What:		/sys/class/ubi/ubiX/ro_mode
111Date:		April 2016
112KernelVersion:	4.7
113Contact:	linux-mtd@lists.infradead.org
114Description:
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
119What:		/sys/class/ubi/ubiX/total_eraseblocks
120Date:		July 2006
121KernelVersion:	2.6.22
122Contact:	Artem Bityutskiy <dedekind@infradead.org>
123Description:
124		Total number of good (not marked as bad) physical eraseblocks on
125		the underlying MTD device.
126
127What:		/sys/class/ubi/ubiX/volumes_count
128Date:		July 2006
129KernelVersion:	2.6.22
130Contact:	Artem Bityutskiy <dedekind@infradead.org>
131Description:
132		Count of volumes on this UBI device.
133
134What:		/sys/class/ubi/ubiX/ubiX_Y/
135Date:		July 2006
136KernelVersion:	2.6.22
137Contact:	Artem Bityutskiy <dedekind@infradead.org>
138Description:
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
143What:		/sys/class/ubi/ubiX/ubiX_Y/alignment
144Date:		July 2006
145KernelVersion:	2.6.22
146Contact:	Artem Bityutskiy <dedekind@infradead.org>
147Description:
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
154What:		/sys/class/ubi/ubiX/ubiX_Y/corrupted
155Date:		July 2006
156KernelVersion:	2.6.22
157Contact:	Artem Bityutskiy <dedekind@infradead.org>
158Description:
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
162What:		/sys/class/ubi/ubiX/ubiX_Y/data_bytes
163Date:		July 2006
164KernelVersion:	2.6.22
165Contact:	Artem Bityutskiy <dedekind@infradead.org>
166Description:
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
171What:		/sys/class/ubi/ubiX/ubiX_Y/dev
172Date:		July 2006
173KernelVersion:	2.6.22
174Contact:	Artem Bityutskiy <dedekind@infradead.org>
175Description:
176		Major and minor numbers of the character device corresponding
177		to this UBI volume (in <major>:<minor> format).
178
179What:		/sys/class/ubi/ubiX/ubiX_Y/name
180Date:		July 2006
181KernelVersion:	2.6.22
182Contact:	Artem Bityutskiy <dedekind@infradead.org>
183Description:
184		Volume name.
185
186What:		/sys/class/ubi/ubiX/ubiX_Y/reserved_ebs
187Date:		July 2006
188KernelVersion:	2.6.22
189Contact:	Artem Bityutskiy <dedekind@infradead.org>
190Description:
191		Count of physical eraseblock reserved for this volume.
192		Equivalent to the volume size in logical eraseblocks.
193
194What:		/sys/class/ubi/ubiX/ubiX_Y/type
195Date:		July 2006
196KernelVersion:	2.6.22
197Contact:	Artem Bityutskiy <dedekind@infradead.org>
198Description:
199		Volume type. Contains ASCII "dynamic\n" for dynamic volumes and
200		"static\n" for static volumes.
201
202What:		/sys/class/ubi/ubiX/ubiX_Y/upd_marker
203Date:		July 2006
204KernelVersion:	2.6.22
205Contact:	Artem Bityutskiy <dedekind@infradead.org>
206Description:
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
214What:		/sys/class/ubi/ubiX/ubiX_Y/usable_eb_size
215Date:		July 2006
216KernelVersion:	2.6.22
217Contact:	Artem Bityutskiy <dedekind@infradead.org>
218Description:
219		Logical eraseblock size of this volume. Equivalent to logical
220		eraseblock size of the device aligned on the volume alignment
221		value.
222