[PATCH] BLOCK: Separate the bounce buffering code from the highmem code [try #6]

Move the bounce buffer code from mm/highmem.c to mm/bounce.c so that it can be
more easily disabled when the block layer is disabled.

!!!NOTE!!! There may be a bug in this code: Should init_emergency_pool() be
	   contingent on CONFIG_HIGHMEM?

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/mm/Makefile b/mm/Makefile
index 6200c6d..4f2166a 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -12,6 +12,9 @@
 			   readahead.o swap.o truncate.o vmscan.o \
 			   prio_tree.o util.o mmzone.o vmstat.o $(mmu-y)
 
+ifeq ($(CONFIG_MMU),y)
+obj-y			+= bounce.o
+endif
 obj-$(CONFIG_SWAP)	+= page_io.o swap_state.o swapfile.o thrash.o
 obj-$(CONFIG_HUGETLBFS)	+= hugetlb.o
 obj-$(CONFIG_NUMA) 	+= mempolicy.o