Now UBIFS is supported by u-boot. If we ever decide to change the
media format, then people will have to upgrade their u-boots to
mount new format images. However, very often it is possible to
preserve R/O forward-compatibility, even though the write
forward-compatibility is not preserved.
This patch introduces a new super-block field which stores the
R/O compatibility version.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Acked-by: Adrian Hunter <Adrian.Hunter@nokia.com>
If data does not compress, it is better to leave it uncompressed
because we'll read it faster then. So do not compress data if we
save less than 64 bytes.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBIFS does not really work correctly when fanout is 2,
because of the way we manage the indexing tree. It may
just become a list and UBIFS screws up.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
At the moment UBIFS reserves twice old index size space for the
index. But this is not enough in some cases, because if the indexing
node are very fragmented and there are many small gaps, while the
dirty index has big znodes - in-the-gaps method would fail.
Thus, reserve trise as more, in which case we are guaranteed that
we can commit in any case.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.html
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
