block: drbd: Convert semaphore to mutex
The bm_change semaphore is semantically a mutex. Convert it to a real
mutex.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index b61057e..f58e765 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -66,7 +66,7 @@
size_t bm_words;
size_t bm_number_of_pages;
sector_t bm_dev_capacity;
- struct semaphore bm_change; /* serializes resize operations */
+ struct mutex bm_change; /* serializes resize operations */
atomic_t bm_async_io;
wait_queue_head_t bm_io_wait;
@@ -114,7 +114,7 @@
return;
}
- trylock_failed = down_trylock(&b->bm_change);
+ trylock_failed = !mutex_trylock(&b->bm_change);
if (trylock_failed) {
dev_warn(DEV, "%s going to '%s' but bitmap already locked for '%s' by %s\n",
@@ -125,7 +125,7 @@
b->bm_task == mdev->receiver.task ? "receiver" :
b->bm_task == mdev->asender.task ? "asender" :
b->bm_task == mdev->worker.task ? "worker" : "?");
- down(&b->bm_change);
+ mutex_lock(&b->bm_change);
}
if (__test_and_set_bit(BM_LOCKED, &b->bm_flags))
dev_err(DEV, "FIXME bitmap already locked in bm_lock\n");
@@ -147,7 +147,7 @@
b->bm_why = NULL;
b->bm_task = NULL;
- up(&b->bm_change);
+ mutex_unlock(&b->bm_change);
}
/* word offset to long pointer */
@@ -295,7 +295,7 @@
if (!b)
return -ENOMEM;
spin_lock_init(&b->bm_lock);
- init_MUTEX(&b->bm_change);
+ mutex_init(&b->bm_change);
init_waitqueue_head(&b->bm_io_wait);
mdev->bitmap = b;