commit 9fb48c744ba6a4bf58b666f4e6fdac3008ea1bd4
author Jim Cromie <jim.cromie@gmail.com> Fri Apr 27 14:30:34 2012 -0600
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> Mon Apr 30 14:05:27 2012 -0400
tree f145e07824a3a9bae9f8da3e5c39ea5073bd872e
parent 3faa286055c02291dc9b6d838601dcb105a64a14

params: add 3rd arg to option handler callback signature

Add a 3rd arg, named "doing", to unknown-options callbacks invoked
from parse_args(). The arg is passed as:

  "Booting kernel" from start_kernel(),
  initcall_level_names[i] from do_initcall_level(),
  mod->name from load_module(), via parse_args(), parse_one()

parse_args() already has the "name" parameter, which is renamed to
"doing" to better reflect current uses 1,2 above.  parse_args() passes
it to an altered parse_one(), which now passes it down into the
unknown option handler callbacks.

The mod->name will be needed to handle dyndbg for loadable modules,
since params passed by modprobe are not qualified (they do not have a
"$modname." prefix), and by the time the unknown-param callback is
called, the module name is not otherwise available.

Minor tweaks:

Add param-name to parse_one's pr_debug(), current message doesnt
identify the param being handled, add it.

Add a pr_info to print current level and level_name of the initcall,
and number of registered initcalls at that level.  This adds 7 lines
to dmesg output, like:

   initlevel:6=device, 172 registered initcalls

Drop "parameters" from initcall_level_names[], its unhelpful in the
pr_info() added above.  This array is passed into parse_args() by
do_initcall_level().

CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kernel/params.c

diff --git a/kernel/params.c b/kernel/params.c
index f37d826..b60e2c7 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -85,11 +85,13 @@
 
 static int parse_one(char *param,
 		     char *val,
+		     const char *doing,
 		     const struct kernel_param *params,
 		     unsigned num_params,
 		     s16 min_level,
 		     s16 max_level,
-		     int (*handle_unknown)(char *param, char *val))
+		     int (*handle_unknown)(char *param, char *val,
+				     const char *doing))
 {
 	unsigned int i;
 	int err;
@@ -104,8 +106,8 @@
 			if (!val && params[i].ops->set != param_set_bool
 			    && params[i].ops->set != param_set_bint)
 				return -EINVAL;
-			pr_debug("They are equal!  Calling %p\n",
-			       params[i].ops->set);
+			pr_debug("handling %s with %p\n", param,
+				params[i].ops->set);
 			mutex_lock(&param_lock);
 			err = params[i].ops->set(val, &params[i]);
 			mutex_unlock(&param_lock);
@@ -114,11 +116,11 @@
 	}
 
 	if (handle_unknown) {
-		pr_debug("Unknown argument: calling %p\n", handle_unknown);
-		return handle_unknown(param, val);
+		pr_debug("doing %s: %s='%s'\n", doing, param, val);
+		return handle_unknown(param, val, doing);
 	}
 
-	pr_debug("Unknown argument `%s'\n", param);
+	pr_debug("Unknown argument '%s'\n", param);
 	return -ENOENT;
 }
 
@@ -175,28 +177,29 @@
 }
 
 /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
-int parse_args(const char *name,
+int parse_args(const char *doing,
 	       char *args,
 	       const struct kernel_param *params,
 	       unsigned num,
 	       s16 min_level,
 	       s16 max_level,
-	       int (*unknown)(char *param, char *val))
+	       int (*unknown)(char *param, char *val, const char *doing))
 {
 	char *param, *val;
 
-	pr_debug("Parsing ARGS: %s\n", args);
-
 	/* Chew leading spaces */
 	args = skip_spaces(args);
 
+	if (args && *args)
+		pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
+
 	while (*args) {
 		int ret;
 		int irq_was_disabled;
 
 		args = next_arg(args, &param, &val);
 		irq_was_disabled = irqs_disabled();
-		ret = parse_one(param, val, params, num,
+		ret = parse_one(param, val, doing, params, num,
 				min_level, max_level, unknown);
 		if (irq_was_disabled && !irqs_disabled()) {
 			printk(KERN_WARNING "parse_args(): option '%s' enabled "
@@ -205,19 +208,19 @@
 		switch (ret) {
 		case -ENOENT:
 			printk(KERN_ERR "%s: Unknown parameter `%s'\n",
-			       name, param);
+			       doing, param);
 			return ret;
 		case -ENOSPC:
 			printk(KERN_ERR
 			       "%s: `%s' too large for parameter `%s'\n",
-			       name, val ?: "", param);
+			       doing, val ?: "", param);
 			return ret;
 		case 0:
 			break;
 		default:
 			printk(KERN_ERR
 			       "%s: `%s' invalid for parameter `%s'\n",
-			       name, val ?: "", param);
+			       doing, val ?: "", param);
 			return ret;
 		}
 	}