Revision 1:
  2.6.0-test10-mm1

Revision 2:
  Experimental version of the snapshot and mirror targets for 2.6.

Revision 3:
  Take a space out of a slab name.

Revision 4:
  take note of the tio->io field before freeing tio.

Revision 5:
  A blk_put_queue() was missing on the error path of alloc_dev().

Revision 6:
  whitespace

Revision 7:
  Set the split io size for the snapshot target.

Revision 8:
  Enable the new code that checks that an exception isn't already being copied.

Revision 9:
  Recheck that the exception hasn't entered the pending table by another
  thread.

Revision 10:
  Set the ti->split_io field for the origin to the smallest chunk-size of its
  snapshots. This is done each time the origin is resumed, since new snapshots
  (with smaller chunk-sizes) could have been added.  [Kevin Corry]

Revision 11:
  In the "else" section of __clone_and_map(), we're splitting a page from the
  bio into two pages and mapping each part separately. Therefore, we need
  another tio structure to track the second part of the page.  [Kevin Corry]

Revision 12:
  In order to properly build snapshot as its own kernel module,
  dm-snapshot.c and dm-snapshot.h must be renamed to dm-snap.c and
  dm-snap.h. The dm_vcalloc function must also be exported from
  dm-table.c so the snapshot module can find it.  [Kevin Corry]

Revision 13:
  Export dm_io_async_bvec so dm-raid1 can find it when built as a module.

Revision 14:
  dm-raid1.c:recover() was assuming that DEFAULT_MIRROR was 0.

Revision 15:
  dm-raid1.c: correct region_shift calculation, ffs defines the
  least-significant bit as 1, not 0.

Revision 16:
  Use s->chunk_size in snapshot ctr rather than the (modified)
  chunk_size var.

Revision 17:
  Use ffs to calculate chunk_shift.

Revision 18:
  Import the 2.4 multipath code (no porting as yet).

Revision 19:
  Mainly looking at the null selector.

Revision 20:
  Change multipath daemon to use dm-daemon.c.
  
  Declare a jiffy_t type in dm.h.
  
  Let daemon work functions return a sleep duration hint (interface
  change only, hint not acted upon yet).

Revision 21:
  Knock out the underscore prefix to static fns.

Revision 22:
  Minor pottering

Revision 23:
  mpath porting

Revision 24:
  Delete null selector.
  
  Add a round robin selector to dm-path-selector.c

Revision 25:
  Change dm-daemon.c to use completions rather than semaphores.
  [Mike Christie]

Revision 26:
  Add in the BIO_RW_FAILFAST flag to the multipath target.
  [Mike Christie]

Revision 27:
  Bug fixes

Revision 28:
  Change the multipath target interface yet again.

Revision 29:
  List targets ioctl.  [Patrick Caulfield]

Revision 30:
  background path testing

Revision 31:
  mpath bug fixes

Revision 32:
  Persistent log for mirroring.  Compiles but not run yet.

Revision 33:
  When adding a new ioctl (DM_LIST_VERSIONS), the MINOR version number of the
  ioctl interface should be incremented.

Revision 34:
  No need to recheck the condition when promoting the write lock in
  multipath_map().

Revision 35:
  Change m->path_lock from a rw semaphore to spinlock, since it
  sometimes needs to be locked from irq context.
  
  NOTE: test_path() is safe to be called from within a spinlock since it
  uses down_trylock() rather than down().