dyndbg: refine export, rename to dynamic_debug_exec_queries()
commit 4c0d77828d4f ("dyndbg: export ddebug_exec_queries") had a few
problems:
- broken non DYNAMIC_DEBUG_CORE configs, sparse warning
- the exported function modifies query string, breaks on RO strings.
- func name follows internal convention, shouldn't be exposed as is.
1st is fixed in header with ifdefd function prototype or stub defn.
Also remove an obsolete HAVE-symbol ifdef-comment, and add others.
Fix others by wrapping existing internal function with a new one,
named in accordance with module-prefix naming convention, before
export hits v5.9.0. In new function, copy query string to a local
buffer, so users can pass hard-coded/RO queries, and internal function
can be used unchanged.
Fixes: 4c0d77828d4f ("dyndbg: export ddebug_exec_queries")
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20200831182210.850852-3-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 01b7d02..08e4b05 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -525,7 +525,7 @@ static int ddebug_exec_query(char *query_string, const char *modname)
last error or number of matching callsites. Module name is either
in param (for boot arg) or perhaps in query string.
*/
-int ddebug_exec_queries(char *query, const char *modname)
+static int ddebug_exec_queries(char *query, const char *modname)
{
char *split;
int i, errs = 0, exitcode = 0, rc, nfound = 0;
@@ -557,7 +557,30 @@ int ddebug_exec_queries(char *query, const char *modname)
return exitcode;
return nfound;
}
-EXPORT_SYMBOL_GPL(ddebug_exec_queries);
+
+/**
+ * dynamic_debug_exec_queries - select and change dynamic-debug prints
+ * @query: query-string described in admin-guide/dynamic-debug-howto
+ * @modname: string containing module name, usually &module.mod_name
+ *
+ * This uses the >/proc/dynamic_debug/control reader, allowing module
+ * authors to modify their dynamic-debug callsites. The modname is
+ * canonically struct module.mod_name, but can also be null or a
+ * module-wildcard, for example: "drm*".
+ */
+int dynamic_debug_exec_queries(const char *query, const char *modname)
+{
+ int rc;
+ char *qry = kstrndup(query, PAGE_SIZE, GFP_KERNEL);
+
+ if (!query)
+ return -ENOMEM;
+
+ rc = ddebug_exec_queries(qry, modname);
+ kfree(qry);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(dynamic_debug_exec_queries);
#define PREFIX_SIZE 64