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>

1 files changed, 13 insertions, 3 deletions

diff --git a/init/initramfs.c b/init/initramfs.c
index 8216c303b082..84c6bf111300 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -1,3 +1,13 @@
+/*
+ * 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/init.h>
 #include <linux/fs.h>
 #include <linux/slab.h>
@@ -74,7 +84,7 @@ static void __init free_hash(void)
         }
 }
 
-static long __init do_utime(char __user *filename, time_t mtime)
+static long __init do_utime(char *filename, time_t mtime)
 {
         struct timespec t[2];
 
@@ -529,7 +539,7 @@ static void __init clean_rootfs(void)
         struct linux_dirent64 *dirp;
         int num;
 
-        fd = sys_open((const char __user __force *) "/", O_RDONLY, 0);
+        fd = sys_open("/", O_RDONLY, 0);
         WARN_ON(fd < 0);
         if (fd < 0)
                 return;
@@ -589,7 +599,7 @@ static int __init populate_rootfs(void)
                 }
                 printk(KERN_INFO "rootfs image is not initramfs (%s)"
                                 "; looks like an initrd\n", err);
-                fd = sys_open((const char __user __force *) "/initrd.image",
+                fd = sys_open("/initrd.image",
                               O_WRONLY|O_CREAT, 0700);
                 if (fd >= 0) {
                         sys_write(fd, (char *)initrd_start,