module_param: allow 'bool' module_params to be bool, not just int.

Impact: API cleanup

For historical reasons, 'bool' parameters must be an int, not a bool.
But there are around 600 users, so a conversion seems like useless churn.

So we use __same_type() to distinguish, and handle both cases.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 26 insertions, 7 deletions

diff --git a/kernel/params.c b/kernel/params.c
index b4660dc13dbc..7f6912ced2ba 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -238,35 +238,54 @@ int param_get_charp(char *buffer, struct kernel_param *kp)
         return sprintf(buffer, "%s", *((char **)kp->arg));
 }
 
+/* Actually could be a bool or an int, for historical reasons. */
 int param_set_bool(const char *val, struct kernel_param *kp)
 {
+        bool v;
+
         /* No equals means "set"... */
         if (!val) val = "1";
 
         /* One of =[yYnN01] */
         switch (val[0]) {
         case 'y': case 'Y': case '1':
-                *(int *)kp->arg = 1;
-                return 0;
+                v = true;
+                break;
         case 'n': case 'N': case '0':
-                *(int *)kp->arg = 0;
-                return 0;
+                v = false;
+                break;
+        default:
+                return -EINVAL;
         }
-        return -EINVAL;
+
+        if (kp->flags & KPARAM_ISBOOL)
+                *(bool *)kp->arg = v;
+        else
+                *(int *)kp->arg = v;
+        return 0;
 }
 
 int param_get_bool(char *buffer, struct kernel_param *kp)
 {
+        bool val;
+        if (kp->flags & KPARAM_ISBOOL)
+                val = *(bool *)kp->arg;
+        else
+                val = *(int *)kp->arg;
+
         /* Y and N chosen as being relatively non-coder friendly */
-        return sprintf(buffer, "%c", (*(int *)kp->arg) ? 'Y' : 'N');
+        return sprintf(buffer, "%c", val ? 'Y' : 'N');
 }
 
+/* This one must be bool. */
 int param_set_invbool(const char *val, struct kernel_param *kp)
 {
-        int boolval, ret;
+        int ret;
+        bool boolval;
         struct kernel_param dummy;
 
         dummy.arg = &boolval;
+        dummy.flags = KPARAM_ISBOOL;
         ret = param_set_bool(val, &dummy);
         if (ret == 0)
                 *(bool *)kp->arg = !boolval;