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path: root/drivers/mtd/ubi/vmt.c
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2008-07-24UBI: fix gcc warningArtem Bityutskiy
Fix the following warning: drivers/mtd/ubi/vmt.c: In function 'ubi_rename_volumes': drivers/mtd/ubi/vmt.c:642: warning: statement with no effect Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-07-24UBI: fix kernel-doc errors and warningsArtem Bityutskiy
No functional changes, just tweak comments to make kernel-doc work fine and stop complaining. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-07-24UBI: fix checkpatch.pl errors and warningsArtem Bityutskiy
Just out or curiousity ran checkpatch.pl for whole UBI, and discovered there are quite a few of stylistic issues. Fix them. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-07-24UBI: implement multiple volumes renameArtem Bityutskiy
Quite useful ioctl which allows to make atomic system upgrades. The idea belongs to Richard Titmuss <richard_titmuss@logitech.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-07-24UBI: fix and re-work debugging stuffArtem Bityutskiy
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-07-24UBI: improve mkvol request validationArtem Bityutskiy
Check that volume name is not shorter than 'name_len'. No need to copy the trailing zero byte because whole array was zeroed earlier. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-07-24UBI: fix memory leakArtem Bityutskiy
ubi_free_volume() function sets ubi->volumes[] to NULL, so ubi_eba_close() is useless, it does not free what has to be freed. So zap it and free vol->eba_tbl at the volume release function. Pointed-out-by: Adrian Hunter <ext-adrian.hunter@nokia.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-07-24UBI: avoid unnecessary division operationsKyungmin Park
UBI already checks that @min io size is the power of 2 at io_init. It is save to use bit operations then. Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-03-04UBI: silence warningS.Çağlar Onur
drivers/mtd/ubi/vmt.c: In function `ubi_create_volume': drivers/mtd/ubi/vmt.c:379: warning: statement with no effect Signed-off-by: S.Çağlar Onur <caglar@pardus.org.tr> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-01-25UBI: add auto-resize featureArtem Bityutskiy
The problem: NAND flashes have different amount of initial bad physical eraseblocks (marked as bad by the manufacturer). For example, for 256MiB Samsung OneNAND flash there might be from 0 to 40 bad initial eraseblocks, which is about 2%. When UBI is used as the base system, one needs to know the exact amount of good physical eraseblocks, because this number is needed to create the UBI image which is put to the devices during production. But this number is not know, which forces us to use the minimum number of good physical eraseblocks. And UBI additionally reserves some percentage of physical eraseblocks for bad block handling (default is 1%), so we have 1-3% of PEBs reserved at the end, depending on the amount of initial bad PEBs. But it is desired to always have 1% (or more, depending on the configuration). Solution: this patch adds an "auto-resize" flag to the volume table. The volume which has the "auto-resize" flag will automatically be re-sized (enlarged) on the first UBI initialization. UBI clears the flag when the volume is re-sized. Only one volume may have the "auto-resize" flag. So, the production UBI image may have one volume with "auto-resize" flag set, and its size is automatically adjusted on the first boot of the device. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-01-25UBI: use bit-fieldsArtem Bityutskiy
Save 12 bytes of RAM per volume by using bit-fields instead of integers. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: bugfix: do not forget to increment vol_countArtem Bityutskiy
When creating a new volume, do not forget to increment the vol_count variable. Also, users are not interested in internal volumes, so do not show them in the volumes_count sysfs file. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: add UBI devices reference countingArtem Bityutskiy
This is one more step on the way to "removable" UBI devices. It adds reference counting for UBI devices. Every time a volume on this device is opened - the device's refcount is increased. It is also increased if someone is reading any sysfs file of this UBI device or of one of its volumes. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: tweak volumes locking some moreArtem Bityutskiy
Make the code more consistent by requiring the caller to lock the ubi->volume_mutex, because this is what we do for updates. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: introduce volume refcountingArtem Bityutskiy
Add ref_count field to UBI volumes and remove weired "vol->removed" field. This way things are better understandable and we do not have to do whold show_attr operation under spinlock. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: fix error pathArtem Bityutskiy
Error path in volume creation is bogus. First of, it ovverrides the 'err' variable and returns zero to the caller. Second, ubi_assert() in the release function is wrong. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: get device when opening volumeArtem Bityutskiy
When a volume is opened, get its kref via get_device() call. And put the reference when closing the volume. With this, we may have a bit saner volume delete. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: tweak volumes lockingArtem Bityutskiy
Transform vtbl_mutex to volumes_mutex - this just makes code easier to understand. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: improve internal interfacesArtem Bityutskiy
Pass volume description object to the EBA function which makes more sense, and EBA function do not have to find the volume description object by volume ID. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: improve error messagesArtem Bityutskiy
Always print error code with error messages, sometimes it is extremely helpful info. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: remove redundant fieldArtem Bityutskiy
Remove redundant ubi->major field - we have it in ubi->cdev.dev already. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: minor tidy-upsArtem Bityutskiy
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-12-26UBI: silence a warningJesper Juhl
This patch silences the following warning : drivers/mtd/ubi/vmt.c:73: warning: 'ret' may be used uninitialized in this function gcc can't see that we always initialize ret in all situations where it is actually used. The one case where it's not initialized is when we BUG(), but gcc doesn't know that we won't then continue and use an uninitialized 'ret'. This patch results in code that does exactely the same as before, but it also makes gcc shut up, so we generate one less line of warning noise. Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-10-14UBI: fix sparse warningsArtem Bityutskiy
Fix "symbol shadows an earlier one" warnings. Although they are harmless but it does not hurt to fix them and make sparse happy. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-07-18UBI: fix overflow bugVinit Agnihotri
I was experiencing overflows in multiplications for volume->used_bytes in vmt.c & vtbl.c, while creating & resizing large volumes. vol->used_bytes is long long however its 2 operands vol->used_ebs & vol->usable_leb_size are int. So their multiplication for larger values causes integer overflows. Typecasting them solves the problem. My machine & flash details: 64Bit dual-core AMD opteron, 1 GB RAM, linux 2.6.18.3. mtd size = 6GB, volume size= 5GB, peb_size = 4MB. heres patch which does the fix. Signed-off-by: Vinit Agnihotri <vinit.agnihotri@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-07-18UBI: fix debugging stuffArtem Bityutskiy
Do not check volumes which are currently in use because thay may be in inconsistent state. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-07-18UBI: bugfix in error pathArtem Bityutskiy
When volume creation fails, we have to set ubi->volumes[vol_id] back to NULL. This patch also tweaks some debugging stuff. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-07-18UBI: kill homegrown endian macrosChristoph Hellwig
Kill UBI's homegrown endianess handling and replace it with the standard kernel endianess handling. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-07-18UBI: error path bugfixArtem Bityutskiy
No need to unlock the lock, this will be done at out_unlock. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2007-04-27UBI: Unsorted Block ImagesArtem B. Bityutskiy
UBI (Latin: "where?") manages multiple logical volumes on a single flash device, specifically supporting NAND flash devices. UBI provides a flexible partitioning concept which still allows for wear-levelling across the whole flash device. In a sense, UBI may be compared to the Logical Volume Manager (LVM). Whereas LVM maps logical sector numbers to physical HDD sector numbers, UBI maps logical eraseblocks to physical eraseblocks. More information may be found at http://www.linux-mtd.infradead.org/doc/ubi.html Partitioning/Re-partitioning An UBI volume occupies a certain number of erase blocks. This is limited by a configured maximum volume size, which could also be viewed as the partition size. Each individual UBI volume's size can be changed independently of the other UBI volumes, provided that the sum of all volume sizes doesn't exceed a certain limit. UBI supports dynamic volumes and static volumes. Static volumes are read-only and their contents are protected by CRC check sums. Bad eraseblocks handling UBI transparently handles bad eraseblocks. When a physical eraseblock becomes bad, it is substituted by a good physical eraseblock, and the user does not even notice this. Scrubbing On a NAND flash bit flips can occur on any write operation, sometimes also on read. If bit flips persist on the device, at first they can still be corrected by ECC, but once they accumulate, correction will become impossible. Thus it is best to actively scrub the affected eraseblock, by first copying it to a free eraseblock and then erasing the original. The UBI layer performs this type of scrubbing under the covers, transparently to the UBI volume users. Erase Counts UBI maintains an erase count header per eraseblock. This frees higher-level layers (like file systems) from doing this and allows for centralized erase count management instead. The erase counts are used by the wear-levelling algorithm in the UBI layer. The algorithm itself is exchangeable. Booting from NAND For booting directly from NAND flash the hardware must at least be capable of fetching and executing a small portion of the NAND flash. Some NAND flash controllers have this kind of support. They usually limit the window to a few kilobytes in erase block 0. This "initial program loader" (IPL) must then contain sufficient logic to load and execute the next boot phase. Due to bad eraseblocks, which may be randomly scattered over the flash device, it is problematic to store the "secondary program loader" (SPL) statically. Also, due to bit-flips it may become corrupted over time. UBI allows to solve this problem gracefully by storing the SPL in a small static UBI volume. UBI volumes vs. static partitions UBI volumes are still very similar to static MTD partitions: * both consist of eraseblocks (logical eraseblocks in case of UBI volumes, and physical eraseblocks in case of static partitions; * both support three basic operations - read, write, erase. But UBI volumes have the following advantages over traditional static MTD partitions: * there are no eraseblock wear-leveling constraints in case of UBI volumes, so the user should not care about this; * there are no bit-flips and bad eraseblocks in case of UBI volumes. So, UBI volumes may be considered as flash devices with relaxed restrictions. Where can it be found? Documentation, kernel code and applications can be found in the MTD gits. What are the applications for? The applications help to create binary flash images for two purposes: pfi files (partial flash images) for in-system update of UBI volumes, and plain binary images, with or without OOB data in case of NAND, for a manufacturing step. Furthermore some tools are/and will be created that allow flash content analysis after a system has crashed.. Who did UBI? The original ideas, where UBI is based on, were developed by Andreas Arnez, Frank Haverkamp and Thomas Gleixner. Josh W. Boyer and some others were involved too. The implementation of the kernel layer was done by Artem B. Bityutskiy. The user-space applications and tools were written by Oliver Lohmann with contributions from Frank Haverkamp, Andreas Arnez, and Artem. Joern Engel contributed a patch which modifies JFFS2 so that it can be run on a UBI volume. Thomas Gleixner did modifications to the NAND layer. Alexander Schmidt made some testing work as well as core functionality improvements. Signed-off-by: Artem B. Bityutskiy <dedekind@linutronix.de> Signed-off-by: Frank Haverkamp <haver@vnet.ibm.com>