firmware_class: Rework usermodehelper check
Instead of two functions, read_lock_usermodehelper() and
usermodehelper_is_disabled(), used in combination, introduce
usermodehelper_read_trylock() that will only return with umhelper_sem
held if usermodehelper_disabled is unset (and will return -EAGAIN
otherwise) and make _request_firmware() use it.
Rename read_unlock_usermodehelper() to
usermodehelper_read_unlock() to follow the naming convention of the
new function.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 6c9387d..deee871 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -533,12 +533,10 @@
return 0;
}
- read_lock_usermodehelper();
-
- if (WARN_ON(usermodehelper_is_disabled())) {
+ retval = usermodehelper_read_trylock();
+ if (WARN_ON(retval)) {
dev_err(device, "firmware: %s will not be loaded\n", name);
- retval = -EBUSY;
- goto out;
+ goto out_nolock;
}
if (uevent)
@@ -573,8 +571,9 @@
fw_destroy_instance(fw_priv);
out:
- read_unlock_usermodehelper();
+ usermodehelper_read_unlock();
+out_nolock:
if (retval) {
release_firmware(firmware);
*firmware_p = NULL;