O'Reilly logo

Mastering Embedded Linux Programming - Second Edition by Chris Simmonds

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

UBI

UBI provides an idealized, reliable view of a flash chip by mapping physical erase blocks (PEB) to logical erase blocks (LEB). Bad blocks are not mapped to LEBs and so are never used. If a block cannot be erased, it is marked as bad and dropped from the mapping. UBI keeps a count of the number of times each PEB has been erased in the header of the LEB and changes the mapping to ensure that each PEB is erased the same number of times.

UBI accesses the flash memory through the MTD layer. As an extra feature, it can divide an MTD partition into a number of UBI volumes, which improves wear leveling in the following way: Imagine that you have two filesystems, one containing fairly static data, for example a root filesystem, and the other containing ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required