kmod: introduce call_modprobe() helper

BugLink: http://bugs.launchpad.net/bugs/963685

No functional changes.  Move the call_usermodehelper code from
__request_module() into the new simple helper, call_modprobe().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 3e63a93b987685f02421e18b2aa452d20553a88b)

Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/kernel/kmod.c b/kernel/kmod.c
index 3502450..b8fad75 100644 (file)
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -58,6 +58,21 @@ static DEFINE_SPINLOCK(umh_sysctl_lock);
 */
 char modprobe_path[KMOD_PATH_LEN] = "/sbin/modprobe";
 
+static int call_modprobe(char *module_name, int wait)
+{
+       static char *envp[] = {
+               "HOME=/",
+               "TERM=linux",
+               "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
+               NULL
+       };
+
+       char *argv[] = { modprobe_path, "-q", "--", module_name, NULL };
+
+       return call_usermodehelper_fns(modprobe_path, argv, envp,
+                                       wait, NULL, NULL, NULL);
+}
+
 /**
  * __request_module - try to load a kernel module
  * @wait: wait (or not) for the operation to complete
@@ -79,11 +94,6 @@ int __request_module(bool wait, const char *fmt, ...)
        char module_name[MODULE_NAME_LEN];
        unsigned int max_modprobes;
        int ret;
-       char *argv[] = { modprobe_path, "-q", "--", module_name, NULL };
-       static char *envp[] = { "HOME=/",
-                               "TERM=linux",
-                               "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
-                               NULL };
        static atomic_t kmod_concurrent = ATOMIC_INIT(0);
 #define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */
        static int kmod_loop_msg;
@@ -126,9 +136,7 @@ int __request_module(bool wait, const char *fmt, ...)
 
        trace_module_request(module_name, wait, _RET_IP_);
 
-       ret = call_usermodehelper_fns(modprobe_path, argv, envp,
-                       wait ? UMH_WAIT_PROC : UMH_WAIT_EXEC,
-                       NULL, NULL, NULL);
+       ret = call_modprobe(module_name, wait ? UMH_WAIT_PROC : UMH_WAIT_EXEC);
 
        atomic_dec(&kmod_concurrent);
        return ret;