The md driver in 2.6 has support for a new style of superblock. This needs user-space support
Apart from a different layout of data, a key difference in the new style superblock is that the kernel will not create these for you. Userspace has to create the array and then ask the kernel to assemble it.
It would make sense to change mdadm do create arrays this way all the time. i.e. to write out the superblocks and then assemble the arrays.
It would be good to keep the code for assembling the array separate so that it can be linked into mdassemble that is small and doesn't waste space on an initramfs.
This needs to be able to read the superblock, compare two superblocks, extract uuid, superminor, number of devices, and raid level/style.
The remainder of the superblock support needs to be able to create superblocks and write them out, and to be able to print out the content in a pretty way.
