is_vmalloc_addr(): Check if an address is within the vmalloc boundaries

Checking if an address is a vmalloc address is done in a couple of places.
Define a common version in mm.h and replace the other checks.

Again the include structures suck.  The definition of VMALLOC_START and
VMALLOC_END is not available in vmalloc.h since highmem.c cannot be included
there.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ntfs/malloc.h b/fs/ntfs/malloc.h
index e38e402..cd0be3f 100644
--- a/fs/ntfs/malloc.h
+++ b/fs/ntfs/malloc.h
@@ -85,8 +85,7 @@
 
 static inline void ntfs_free(void *addr)
 {
-	if (likely(((unsigned long)addr < VMALLOC_START) ||
-			((unsigned long)addr >= VMALLOC_END ))) {
+	if (!is_vmalloc_addr(addr)) {
 		kfree(addr);
 		/* free_page((unsigned long)addr); */
 		return;
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 1be7308..7dd26e1 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -325,7 +325,7 @@
 		if (m == NULL) {
 			if (clear_user(buffer, tsz))
 				return -EFAULT;
-		} else if ((start >= VMALLOC_START) && (start < VMALLOC_END)) {
+		} else if (is_vmalloc_addr((void *)start)) {
 			char * elf_buf;
 			struct vm_struct *m;
 			unsigned long curstart = start;
diff --git a/fs/xfs/linux-2.6/kmem.c b/fs/xfs/linux-2.6/kmem.c
index ed2b16d..e040f1c 100644
--- a/fs/xfs/linux-2.6/kmem.c
+++ b/fs/xfs/linux-2.6/kmem.c
@@ -92,8 +92,7 @@
 void
 kmem_free(void *ptr, size_t size)
 {
-	if (((unsigned long)ptr < VMALLOC_START) ||
-	    ((unsigned long)ptr >= VMALLOC_END)) {
+	if (!is_vmalloc_addr(ptr)) {
 		kfree(ptr);
 	} else {
 		vfree(ptr);
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index a49dd8d..0382c19 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -709,8 +709,7 @@
 mem_to_page(
 	void			*addr)
 {
-	if (((unsigned long)addr < VMALLOC_START) ||
-	    ((unsigned long)addr >= VMALLOC_END)) {
+	if ((!is_vmalloc_addr(addr))) {
 		return virt_to_page(addr);
 	} else {
 		return vmalloc_to_page(addr);