xref: /linux/Documentation/ABI/stable/sysfs-class-ubi (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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/total_eraseblocks
111Date:		July 2006
112KernelVersion:	2.6.22
113Contact:	Artem Bityutskiy <dedekind@infradead.org>
114Description:
115		Total number of good (not marked as bad) physical eraseblocks on
116		the underlying MTD device.
117
118What:		/sys/class/ubi/ubiX/volumes_count
119Date:		July 2006
120KernelVersion:	2.6.22
121Contact:	Artem Bityutskiy <dedekind@infradead.org>
122Description:
123		Count of volumes on this UBI device.
124
125What:		/sys/class/ubi/ubiX/ubiX_Y/
126Date:		July 2006
127KernelVersion:	2.6.22
128Contact:	Artem Bityutskiy <dedekind@infradead.org>
129Description:
130		The /sys/class/ubi/ubiX/ubiX_0/, /sys/class/ubi/ubiX/ubiX_1/,
131		etc directories describe UBI volumes on UBI device X (volumes
132		0, 1, etc).
133
134What:		/sys/class/ubi/ubiX/ubiX_Y/alignment
135Date:		July 2006
136KernelVersion:	2.6.22
137Contact:	Artem Bityutskiy <dedekind@infradead.org>
138Description:
139		Volume alignment - the value the logical eraseblock size of
140		this volume has to be aligned on. For example, 2048 means that
141		logical eraseblock size is multiple of 2048. In other words,
142		volume logical eraseblock size is UBI device logical eraseblock
143		size aligned to the alignment value.
144
145What:		/sys/class/ubi/ubiX/ubiX_Y/corrupted
146Date:		July 2006
147KernelVersion:	2.6.22
148Contact:	Artem Bityutskiy <dedekind@infradead.org>
149Description:
150		Contains ASCII "0\n" if the UBI volume is OK, and ASCII "1\n"
151		if it is corrupted (e.g., due to an interrupted volume update).
152
153What:		/sys/class/ubi/ubiX/ubiX_Y/data_bytes
154Date:		July 2006
155KernelVersion:	2.6.22
156Contact:	Artem Bityutskiy <dedekind@infradead.org>
157Description:
158		The amount of data this volume contains. This value makes sense
159		only for static volumes, and for dynamic volume it equivalent
160		to the total volume size in bytes.
161
162What:		/sys/class/ubi/ubiX/ubiX_Y/dev
163Date:		July 2006
164KernelVersion:	2.6.22
165Contact:	Artem Bityutskiy <dedekind@infradead.org>
166Description:
167		Major and minor numbers of the character device corresponding
168		to this UBI volume (in <major>:<minor> format).
169
170What:		/sys/class/ubi/ubiX/ubiX_Y/name
171Date:		July 2006
172KernelVersion:	2.6.22
173Contact:	Artem Bityutskiy <dedekind@infradead.org>
174Description:
175		Volume name.
176
177What:		/sys/class/ubi/ubiX/ubiX_Y/reserved_ebs
178Date:		July 2006
179KernelVersion:	2.6.22
180Contact:	Artem Bityutskiy <dedekind@infradead.org>
181Description:
182		Count of physical eraseblock reserved for this volume.
183		Equivalent to the volume size in logical eraseblocks.
184
185What:		/sys/class/ubi/ubiX/ubiX_Y/type
186Date:		July 2006
187KernelVersion:	2.6.22
188Contact:	Artem Bityutskiy <dedekind@infradead.org>
189Description:
190		Volume type. Contains ASCII "dynamic\n" for dynamic volumes and
191		"static\n" for static volumes.
192
193What:		/sys/class/ubi/ubiX/ubiX_Y/upd_marker
194Date:		July 2006
195KernelVersion:	2.6.22
196Contact:	Artem Bityutskiy <dedekind@infradead.org>
197Description:
198		Contains ASCII "0\n" if the update marker is not set for this
199		volume, and "1\n" if it is set. The update marker is set when
200		volume update starts, and cleaned when it ends. So the presence
201		of the update marker indicates that the volume is being updated
202		at the moment of the update was interrupted. The later may be
203		checked using the "corrupted" sysfs file.
204
205What:		/sys/class/ubi/ubiX/ubiX_Y/usable_eb_size
206Date:		July 2006
207KernelVersion:	2.6.22
208Contact:	Artem Bityutskiy <dedekind@infradead.org>
209Description:
210		Logical eraseblock size of this volume. Equivalent to logical
211		eraseblock size of the device aligned on the volume alignment
212		value.
213