
While MFS failing to do I/O on a block is generally fatal, reading the superblock at mount time is an exception: this case may occur when the given partition is too small to contain the superblock. Therefore, MFS should not crash or even report anything in this case, but rather refuse to mount cleanly. This fixes #121. Change-Id: I11326b48922a0e0ebefecbb8eec7c428f985f2b3