module_param: split perm field into flags and perm
Impact: cleanup
Rather than hack KPARAM_KMALLOCED into the perm field, separate it out.
Since the perm field was 32 bits and only needs 16, we don't add bloat.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h
index 9bbca8e..009a5f7 100644
--- a/include/linux/moduleparam.h
+++ b/include/linux/moduleparam.h
@@ -36,9 +36,13 @@
/* Returns length written or -errno. Buffer is 4k (ie. be short!) */
typedef int (*param_get_fn)(char *buffer, struct kernel_param *kp);
+/* Flag bits for kernel_param.flags */
+#define KPARAM_KMALLOCED 1
+
struct kernel_param {
const char *name;
- unsigned int perm;
+ u16 perm;
+ u16 flags;
param_set_fn set;
param_get_fn get;
union {
@@ -88,7 +92,7 @@
static struct kernel_param __moduleparam_const __param_##name \
__used \
__attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
- = { __param_str_##name, perm, set, get, { arg } }
+ = { __param_str_##name, perm, 0, set, get, { arg } }
#define module_param_call(name, set, get, arg, perm) \
__module_param_call(MODULE_PARAM_PREFIX, name, set, get, arg, perm)
diff --git a/kernel/params.c b/kernel/params.c
index 023abbf..b4660dc 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -24,9 +24,6 @@
#include <linux/err.h>
#include <linux/slab.h>
-/* We abuse the high bits of "perm" to record whether we kmalloc'ed. */
-#define KPARAM_KMALLOCED 0x80000000
-
#if 0
#define DEBUGP printk
#else
@@ -220,13 +217,13 @@
return -ENOSPC;
}
- if (kp->perm & KPARAM_KMALLOCED)
+ if (kp->flags & KPARAM_KMALLOCED)
kfree(*(char **)kp->arg);
/* This is a hack. We can't need to strdup in early boot, and we
* don't need to; this mangled commandline is preserved. */
if (slab_is_available()) {
- kp->perm |= KPARAM_KMALLOCED;
+ kp->flags |= KPARAM_KMALLOCED;
*(char **)kp->arg = kstrdup(val, GFP_KERNEL);
if (!kp->arg)
return -ENOMEM;
@@ -591,7 +588,7 @@
unsigned int i;
for (i = 0; i < num; i++)
- if (params[i].perm & KPARAM_KMALLOCED)
+ if (params[i].flags & KPARAM_KMALLOCED)
kfree(*(char **)params[i].arg);
}