uml: remove page_size()

userspace code used to have to call the kernelspace function page_size() in
order to determine the value of the kernel's PAGE_SIZE.  Since this is now
available directly from kern_constants.h as UM_KERN_PAGE_SIZE, page_size() can
be deleted and calls changed to use the constant.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/um/os-Linux/tt.c b/arch/um/os-Linux/tt.c
index 00e14f4..bcf9359 100644
--- a/arch/um/os-Linux/tt.c
+++ b/arch/um/os-Linux/tt.c
@@ -31,6 +31,7 @@
 #include "choose-mode.h"
 #include "mode.h"
 #include "tempfile.h"
+#include "kern_constants.h"
 
 int protect_memory(unsigned long addr, unsigned long len, int r, int w, int x,
 		   int must_succeed)
@@ -142,7 +143,7 @@
 	int sig = sigkill;
 
 	t = arg;
-	t->pid = clone(t->tramp, (void *) t->temp_stack + page_size()/2,
+	t->pid = clone(t->tramp, (void *) t->temp_stack + UM_KERN_PAGE_SIZE/2,
 		       t->flags, t->tramp_data);
 	if(t->pid > 0) wait_for_stop(t->pid, SIGSTOP, PTRACE_CONT, NULL);
 	kill(os_getpid(), sig);