metag: fix put_user sparse errors

virtio wants to write bitwise types to userspace using put_user.
At the moment this triggers sparse errors, since the value is passed
through an integer.

For example:

	__le32 __user *p;
	__le32 x;
	put_user(x, p);

is safe, but currently triggers a sparse warning.

Fix that up using __force.

This also fixes warnings due to writing a pointer out to
userland.

Note: this does not suppress any useful sparse checks since callers
do a cast (__typeof__(*(ptr))) (x) which in turn forces all the
necessary type checks.

Suggested-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: James Hogan <james.hogan@imgtec.com>

1 files changed, 13 insertions, 8 deletions

diff --git a/arch/metag/include/asm/uaccess.h b/arch/metag/include/asm/uaccess.h
index fd863fead4af..8282cbce7e39 100644
--- a/arch/metag/include/asm/uaccess.h
+++ b/arch/metag/include/asm/uaccess.h
@@ -107,18 +107,23 @@ extern long __put_user_asm_w(unsigned int x, void __user *addr);
 extern long __put_user_asm_d(unsigned int x, void __user *addr);
 extern long __put_user_asm_l(unsigned long long x, void __user *addr);
 
-#define __put_user_size(x, ptr, size, retval)                   \
-do {                                                            \
-        retval = 0;                                             \
-        switch (size) {                                         \
+#define __put_user_size(x, ptr, size, retval)                           \
+do {                                                                    \
+        retval = 0;                                                     \
+        switch (size) {                                                 \
         case 1:                                                         \
-                retval = __put_user_asm_b((unsigned int)x, ptr); break; \
+                retval = __put_user_asm_b((__force unsigned int)x, ptr);\
+                break;                                                  \
         case 2:                                                         \
-                retval = __put_user_asm_w((unsigned int)x, ptr); break; \
+                retval = __put_user_asm_w((__force unsigned int)x, ptr);\
+                break;                                                  \
         case 4:                                                         \
-                retval = __put_user_asm_d((unsigned int)x, ptr); break; \
+                retval = __put_user_asm_d((__force unsigned int)x, ptr);\
+                break;                                                  \
         case 8:                                                         \
-                retval = __put_user_asm_l((unsigned long long)x, ptr); break; \
+                retval = __put_user_asm_l((__force unsigned long long)x,\
+                                          ptr);                         \
+                break;                                                  \
         default:                                                        \
                 __put_user_bad();                                       \
         }                                                               \