init: disable sparse checking of the mount.o source files

The init/mount.o source files produce a number of sparse warnings of the
type:

warning: incorrect type in argument 1 (different address spaces)
   expected char [noderef] <asn:1>*dev_name
   got char *name

This is due to the syscalls expecting some of the arguments to be user
pointers but they are being passed as kernel pointers.  This is harmless
but adds a lot of noise to a sparse build.

To limit the noise just disable the sparse checking in the relevant source
files, but still display a warning so that the user knows this has been
done.

Since the sparse checking has been disabled we can also remove the __user
__force casts that are scattered thru the source.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/init/do_mounts_rd.c b/init/do_mounts_rd.c
index 6212586..6be2879 100644
--- a/init/do_mounts_rd.c
+++ b/init/do_mounts_rd.c
@@ -1,3 +1,12 @@
+/*
+ * Many of the syscalls used in this file expect some of the arguments
+ * to be __user pointers not __kernel pointers.  To limit the sparse
+ * noise, turn off sparse checking for this file.
+ */
+#ifdef __CHECKER__
+#undef __CHECKER__
+#warning "Sparse checking disabled for this file"
+#endif
 
 #include <linux/kernel.h>
 #include <linux/fs.h>
@@ -181,7 +190,7 @@
 	char rotator[4] = { '|' , '/' , '-' , '\\' };
 #endif
 
-	out_fd = sys_open((const char __user __force *) "/dev/ram", O_RDWR, 0);
+	out_fd = sys_open("/dev/ram", O_RDWR, 0);
 	if (out_fd < 0)
 		goto out;
 
@@ -280,7 +289,7 @@
 	sys_close(out_fd);
 out:
 	kfree(buf);
-	sys_unlink((const char __user __force *) "/dev/ram");
+	sys_unlink("/dev/ram");
 	return res;
 }