blktap2: Remap kernel address ranges through the tapdisk mm.

Avoid init_mm, which isn't exported to modules anymore.

Signed-off-by: Daniel Stodden <daniel.stodden@xxxxxxxxxx>

diff -r e387b1974af5 drivers/xen/blktap/device.c
--- a/drivers/xen/blktap/device.c	Tue Feb 02 19:06:52 2010 -0800
+++ b/drivers/xen/blktap/device.c	Wed Feb 03 11:35:24 2010 -0800
@@ -323,7 +323,7 @@
 		      request->handles[i].user);
 
 		if (request->handles[i].kernel == INVALID_GRANT_HANDLE) {
-			blktap_umap_uaddr(&init_mm, kvaddr);
+			blktap_umap_uaddr(tap->ring.vma->vm_mm, kvaddr);
 			flush_tlb_kernel_page(kvaddr);
 			set_phys_to_machine(__pa(kvaddr) >> PAGE_SHIFT,
 					    INVALID_P2M_ENTRY);
@@ -561,7 +561,7 @@
 	pte = mk_pte(page, ring->vma->vm_page_prot);
 	blktap_map_uaddr(ring->vma->vm_mm, uvaddr, pte_mkwrite(pte));
 	flush_tlb_page(ring->vma, uvaddr);
-	blktap_map_uaddr(&init_mm, kvaddr, mk_pte(page, PAGE_KERNEL));
+	blktap_map_uaddr(ring->vma->vm_mm, kvaddr, mk_pte(page, PAGE_KERNEL));
 	flush_tlb_kernel_page(kvaddr);
 
 	set_phys_to_machine(__pa(kvaddr) >> PAGE_SHIFT, pte_mfn(pte));
diff -r e387b1974af5 mm/init-mm.c
--- a/mm/init-mm.c	Tue Feb 02 19:06:52 2010 -0800
+++ b/mm/init-mm.c	Wed Feb 03 11:35:24 2010 -0800
@@ -4,7 +4,6 @@
 #include <linux/spinlock.h>
 #include <linux/list.h>
 #include <linux/cpumask.h>
-#include <linux/module.h>
 
 #include <asm/atomic.h>
 #include <asm/pgtable.h>
@@ -19,4 +18,3 @@
 	.mmlist		= LIST_HEAD_INIT(init_mm.mmlist),
 	.cpu_vm_mask	= CPU_MASK_ALL,
 };
-EXPORT_SYMBOL_GPL(init_mm);