From 75c43b6ec6eb114e875e43fb151987c1a558e4f4 Mon Sep 17 00:00:00 2001 From: Daniel Walker Date: Mon, 4 Feb 2008 23:57:42 -0800 Subject: [PATCH] USB: libusual: locking cleanup I converted the usu_init_notify semaphore to normal mutex usage, and it should still prevent the request_module before the init routine is complete. Before it acted more like a complete, now the mutex protects two distinct section from running at the same time. Signed-off-by: Daniel Walker Cc: Pete Zaitcev Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/usb/storage/libusual.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/usb/storage/libusual.c b/drivers/usb/storage/libusual.c index 55b9520..a28d491 100644 --- a/drivers/usb/storage/libusual.c +++ b/drivers/usb/storage/libusual.c @@ -9,6 +9,7 @@ #include #include #include +#include /* */ @@ -30,7 +31,7 @@ static atomic_t usu_bias = ATOMIC_INIT(USB_US_DEFAULT_BIAS); #define BIAS_NAME_SIZE (sizeof("usb-storage")) static const char *bias_names[3] = { "none", "usb-storage", "ub" }; -static struct semaphore usu_init_notify; +static DEFINE_MUTEX(usu_probe_mutex); static DECLARE_COMPLETION(usu_end_notify); static atomic_t total_threads = ATOMIC_INIT(0); @@ -178,10 +179,7 @@ static int usu_probe_thread(void *arg) int rc; unsigned long flags; - /* A completion does not work here because it's counted. */ - down(&usu_init_notify); - up(&usu_init_notify); - + mutex_lock(&usu_probe_mutex); rc = request_module(bias_names[type]); spin_lock_irqsave(&usu_lock, flags); if (rc == 0 && (st->fls & USU_MOD_FL_PRESENT) == 0) { @@ -194,6 +192,7 @@ static int usu_probe_thread(void *arg) } st->fls &= ~USU_MOD_FL_THREAD; spin_unlock_irqrestore(&usu_lock, flags); + mutex_unlock(&usu_probe_mutex); complete_and_exit(&usu_end_notify, 0); } @@ -204,10 +203,9 @@ static int __init usb_usual_init(void) { int rc; - sema_init(&usu_init_notify, 0); - + mutex_lock(&usu_probe_mutex); rc = usb_register(&usu_driver); - up(&usu_init_notify); + mutex_unlock(&usu_probe_mutex); return rc; } -- 1.8.2.3