summaryrefslogtreecommitdiff
path: root/fs/ubifs/ubifs-media.h
AgeCommit message (Collapse)Author
2016-12-12ubifs: Raise write version to 5Richard Weinberger
Starting with version 5 the following properties change: - UBIFS_FLG_DOUBLE_HASH is mandatory - UBIFS_FLG_ENCRYPTION is optional but depdens on UBIFS_FLG_DOUBLE_HASH - Filesystems with unknown super block flags will be rejected, this allows us in future to add new features without raising the UBIFS write version. Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12ubifs: Implement UBIFS_FLG_ENCRYPTIONRichard Weinberger
This feature flag indicates that the filesystem contains encrypted files. Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12ubifs: Implement UBIFS_FLG_DOUBLE_HASHRichard Weinberger
This feature flag indicates that all directory entry nodes have a 32bit cookie set and therefore UBIFS is allowed to perform lookups by hash. Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12ubifs: Add full hash lookup supportRichard Weinberger
UBIFS stores a 32bit hash of every file, for traditional lookups by name this scheme is fine since UBIFS can first try to find the file by the hash of the filename and upon collisions it can walk through all entries with the same hash and do a string compare. When filesnames are encrypted fscrypto will ask the filesystem for a unique cookie, based on this cookie the filesystem has to be able to locate the target file again. With 32bit hashes this is impossible because the chance for collisions is very high. Do deal with that we store a 32bit cookie directly in the UBIFS directory entry node such that we get a 64bit cookie (32bit from filename hash and the dent cookie). For a lookup by hash UBIFS finds the entry by the first 32bit and then compares the dent cookie. If it does not match, it has to do a linear search of the whole directory and compares all dent cookies until the correct entry is found. Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12ubifs: Introduce new data node field, compr_sizeRichard Weinberger
When data of a data node is compressed and encrypted we need to store the size of the compressed data because before encryption we may have to add padding bytes. For the new field we consume the last two padding bytes in struct ubifs_data_node. Two bytes are fine because the data length is at most 4096. Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12ubifs: Add skeleton for fscryptoRichard Weinberger
This is the first building block to provide file level encryption on UBIFS. Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12ubifs: Define UBIFS crypto context xattrRichard Weinberger
Like ext4 UBIFS will store the crypto context in a xattr attribute. Signed-off-by: Richard Weinberger <richard@nod.at>
2011-05-16UBIFS: add a superblock flag for free space fix-upMatthew L. Creech
The 'space_fixup' flag can be set in the superblock of a new filesystem by mkfs.ubifs to indicate that any eraseblocks with free space remaining should be fixed-up the first time it's mounted (after which the flag is un-set). This means that the UBIFS image has been flashed by a "dumb" flasher and the free space has been actually programmed (writing all 0xFFs), so this free space cannot be used. UBIFS fixes the free space up by re-writing the contents of all LEBs with free space using the atomic LEB change UBI operation. Artem: improved commit message, add some more commentaries to the code. Signed-off-by: Matthew L. Creech <mlcreech@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: use __packed instead of __attribute__((packed))Artem Bityutskiy
There was an attempt to standartize various "__attribute__" and other macros in order to have potentially portable and more consistent code, see commit 82ddcb040570411fc2d421d96b3e69711c670328. Note, that commit refers Rober Love's blog post, but the URL is broken, the valid URL is: http://blog.rlove.org/2005/10/with-little-help-from-your-compiler.html Moreover, nowadays checkpatch.pl warns about using __attribute__((packed)): "WARNING: __packed is preferred over __attribute__((packed))" It is not a big deal for UBIFS to use __packed, so let's do it. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-09-15UBIFS: define journal head numbers in ubifs-media.hArtem Bityutskiy
The journal head names and numbers are part of the UBIFS format, so they should be in the ubifs-media.h. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-03-26UBIFS: add R/O compatibilityArtem Bityutskiy
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>
2008-12-03UBIFS: slight compression optimizationArtem Bityutskiy
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>
2008-09-30UBIFS: ensure data read beyond i_size is zeroed out correctlyAdrian Hunter
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-09-05UBIFS: make minimum fanout 3Artem Bityutskiy
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>
2008-08-13UBIFS: reserve more space for indexArtem Bityutskiy
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>
2008-07-15UBIFS: add new flash file systemArtem Bityutskiy
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>