diff --git a/drivers/staging/lustre/lustre/llite/llite_internal.h b/drivers/staging/lustre/lustre/llite/llite_internal.h
index d2f8250b87f1cd7a27a9ade5183f20c841f7fb2e..f4b15bf8423624b2a3ab45d9321eeb0db844ff74 100644
--- a/drivers/staging/lustre/lustre/llite/llite_internal.h
+++ b/drivers/staging/lustre/lustre/llite/llite_internal.h
@@ -211,8 +211,7 @@ struct ll_inode_info {
 
 		/* for non-directory */
 		struct {
-			struct semaphore		f_size_sem;
-			void				*f_size_sem_owner;
+			struct mutex			f_size_mutex;
 			char				*f_symlink_name;
 			__u64				f_maxbytes;
 			/*
@@ -249,8 +248,7 @@ struct ll_inode_info {
 			char		     f_jobid[JOBSTATS_JOBID_SIZE];
 		} f;
 
-#define lli_size_sem	    u.f.f_size_sem
-#define lli_size_sem_owner      u.f.f_size_sem_owner
+#define lli_size_mutex          u.f.f_size_mutex
 #define lli_symlink_name	u.f.f_symlink_name
 #define lli_maxbytes	    u.f.f_maxbytes
 #define lli_trunc_sem	   u.f.f_trunc_sem
@@ -319,7 +317,7 @@ int ll_xattr_cache_get(struct inode *inode,
  * Locking to guarantee consistency of non-atomic updates to long long i_size,
  * consistency between file size and KMS.
  *
- * Implemented by ->lli_size_sem and ->lsm_lock, nested in that order.
+ * Implemented by ->lli_size_mutex and ->lsm_lock, nested in that order.
  */
 
 void ll_inode_size_lock(struct inode *inode);
@@ -1448,7 +1446,7 @@ static inline void cl_isize_unlock(struct inode *inode)
 
 static inline void cl_isize_write_nolock(struct inode *inode, loff_t kms)
 {
-	LASSERT(down_trylock(&ll_i2info(inode)->lli_size_sem) != 0);
+	LASSERT(mutex_is_locked(&ll_i2info(inode)->lli_size_mutex));
 	i_size_write(inode, kms);
 }
 
diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c
index befc30b22bc14b7f8e222c127773a52a91b8bd78..34df5d9370073bf905f0d4b0dc791f7e43af844b 100644
--- a/drivers/staging/lustre/lustre/llite/llite_lib.c
+++ b/drivers/staging/lustre/lustre/llite/llite_lib.c
@@ -982,8 +982,7 @@ void ll_lli_init(struct ll_inode_info *lli)
 		spin_lock_init(&lli->lli_sa_lock);
 		lli->lli_opendir_pid = 0;
 	} else {
-		sema_init(&lli->lli_size_sem, 1);
-		lli->lli_size_sem_owner = NULL;
+		mutex_init(&lli->lli_size_mutex);
 		lli->lli_symlink_name = NULL;
 		init_rwsem(&lli->lli_trunc_sem);
 		mutex_init(&lli->lli_write_mutex);
@@ -1700,10 +1699,7 @@ void ll_inode_size_lock(struct inode *inode)
 	LASSERT(!S_ISDIR(inode->i_mode));
 
 	lli = ll_i2info(inode);
-	LASSERT(lli->lli_size_sem_owner != current);
-	down(&lli->lli_size_sem);
-	LASSERT(lli->lli_size_sem_owner == NULL);
-	lli->lli_size_sem_owner = current;
+	mutex_lock(&lli->lli_size_mutex);
 }
 
 void ll_inode_size_unlock(struct inode *inode)
@@ -1711,9 +1707,7 @@ void ll_inode_size_unlock(struct inode *inode)
 	struct ll_inode_info *lli;
 
 	lli = ll_i2info(inode);
-	LASSERT(lli->lli_size_sem_owner == current);
-	lli->lli_size_sem_owner = NULL;
-	up(&lli->lli_size_sem);
+	mutex_unlock(&lli->lli_size_mutex);
 }
 
 void ll_update_inode(struct inode *inode, struct lustre_md *md)