Apply all of these to the core kernel:
  -mempool.patch    - sct's backport
  -vcalloc.patch    - a calloc implementation (with overflow check)
  -o_direct.patch   - avoid atime updates that can deadlock under low memory

And this one too:
  -b_private.patch  - buffer head changes

These patches provide the core driver and implement basic mapping functions:
  -config.patch     - add device-mapper option (tagged experimental)
  -devmapper.patch  - the driver, including snapshot support
  -makefile.patch   - the md makefile changes

And for 64-bit architectures:
  -arch64.patch