moduleparam: fix alpha, ia64 and ppc64 compile failures

[upstream commit: 91d35dd9]

On alpha, ia64 and ppc64 only relocations to local data can go into
read-only sections. The vast majority of module parameters use the global
generic param_set_*/param_get_* functions, so the 'const' attribute for
struct kernel_param is not only useless, but it also causes compile
failures due to 'section type conflict' in those rare cases where
param_set/get are local functions.

This fixes http://bugzilla.kernel.org/show_bug.cgi?id=8964

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Pagano <mpagano@gentoo.org>
[chrisw@sous-sol.org: backport to 2.6.24.3]
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h
index 13410b20600f4a33284da6252cc7beeb99c9f105..c1d64c2f9360f90d7bdaa2cb700108c410bb64a4 100644 (file)
--- a/include/linux/moduleparam.h
+++ b/include/linux/moduleparam.h
@@ -62,6 +62,16 @@ struct kparam_array
        void *elem;
 };
 
+/* On alpha, ia64 and ppc64 relocations to global data cannot go into
+   read-only sections (which is part of respective UNIX ABI on these
+   platforms). So 'const' makes no sense and even causes compile failures
+   with some compilers. */
+#if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64)
+#define __moduleparam_const
+#else
+#define __moduleparam_const const
+#endif
+
 /* This is the fundamental function for registering boot/module
    parameters.  perm sets the visibility in sysfs: 000 means it's
    not there, read bits mean it's readable, write bits mean it's
@@ -71,7 +81,7 @@ struct kparam_array
        static int __param_perm_check_##name __attribute__((unused)) =  \
        BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2)); \
        static const char __param_str_##name[] = prefix #name;          \
-       static struct kernel_param const __param_##name                 \
+       static struct kernel_param __moduleparam_const __param_##name   \
        __attribute_used__                                              \
     __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
        = { __param_str_##name, perm, set, get, { arg } }