arm: add arch_mmap_check(), get rid of sys_arm_mremap()

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/arm/include/asm/mman.h

 #include <asm-generic/mman.h>
+
+#define arch_mmap_check(addr, len, flags) \
+	(((flags) & MAP_FIXED && (addr) < FIRST_USER_ADDRESS) ? -EINVAL : 0)

arch/arm/kernel/calls.S

@@ -172,7 +172,7 @@
 /* 160 */	CALL(sys_sched_get_priority_min)
 		CALL(sys_sched_rr_get_interval)
 		CALL(sys_nanosleep)
-		CALL(sys_arm_mremap)
+		CALL(sys_mremap)
 		CALL(sys_setresuid16)
 /* 165 */	CALL(sys_getresuid16)
 		CALL(sys_ni_syscall)		/* vm86 */

arch/arm/kernel/sys_arm.c

@@ -28,10 +28,6 @@
 #include <linux/ipc.h>
 #include <linux/uaccess.h>
 
-extern unsigned long do_mremap(unsigned long addr, unsigned long old_len,
-			       unsigned long new_len, unsigned long flags,
-			       unsigned long new_addr);
-
 /* common code for old and new mmaps */
 inline long do_mmap2(
 	unsigned long addr, unsigned long len,
@@ -43,9 +39,6 @@ inline long do_mmap2(
 
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 
-	if (flags & MAP_FIXED && addr < FIRST_USER_ADDRESS)
-		goto out;
-
 	error = -EBADF;
 	if (!(flags & MAP_ANONYMOUS)) {
 		file = fget(fd);
@@ -89,24 +82,6 @@ asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
 	return error;
 }
 
-asmlinkage unsigned long
-sys_arm_mremap(unsigned long addr, unsigned long old_len,
-	       unsigned long new_len, unsigned long flags,
-	       unsigned long new_addr)
-{
-	unsigned long ret = -EINVAL;
-
-	if (flags & MREMAP_FIXED && new_addr < FIRST_USER_ADDRESS)
-		goto out;
-
-	down_write(&current->mm->mmap_sem);
-	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
-	up_write(&current->mm->mmap_sem);
-
-out:
-	return ret;
-}
-
 /*
  * Perform the select(nd, in, out, ex, tv) and mmap() system
  * calls.