[PATCH 7/7] zram/xvmalloc: combine duplicate block delete code

[Pekka Enberg]

On Fri, 2011-01-28 at 09:01 -0600, Robert Jennings wrote:
> This patch eliminates duplicate code.  The remove_block_head function
> is a special case of remove_block which can be contained in remove_block
> without confusion.
> 
> The portion of code in remove_block_head which was noted as "DEBUG ONLY"
> is now mandatory.  Doing this provides consistent management of the double
> linked list of blocks under a freelist and makes this consolidation
> of delete block code safe.  The first and last blocks will have NULL
> pointers in their previous and next page pointers respectively.
> 
> Additionally, any time a block is removed from a free list the next and
> previous pointers will be set to NULL to avoid misuse outside xvmalloc.
> 
> Signed-off-by: Robert Jennings <rcj at linux.vnet.ibm.com>

Looks OK to me but we should really get Nitin's ACK for this.

Reviewed-by: Pekka Enberg <penberg at kernel.org>