2 files changed, 26 insertions, 13 deletions

diff --git a/fs/locks.c b/fs/locks.c
index 749a0dc7cd4b..a31648e3ec1b 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1611,6 +1611,24 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
         return error;
 }
 
+/**
+ * vfs_test_lock - test file byte range lock
+ * @filp: The file to test lock for
+ * @fl: The lock to test
+ * @conf: Place to return a copy of the conflicting lock, if found
+ *
+ * Returns -ERRNO on failure.  Indicates presence of conflicting lock by
+ * setting conf->fl_type to something other than F_UNLCK.
+ */
+int vfs_test_lock(struct file *filp, struct file_lock *fl)
+{
+        if (filp->f_op && filp->f_op->lock)
+                return filp->f_op->lock(filp, F_GETLK, fl);
+        posix_test_lock(filp, fl);
+        return 0;
+}
+EXPORT_SYMBOL_GPL(vfs_test_lock);
+
 static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl)
 {
         flock->l_pid = fl->fl_pid;
@@ -1663,12 +1681,9 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
         if (error)
                 goto out;
 
-        if (filp->f_op && filp->f_op->lock) {
-                error = filp->f_op->lock(filp, F_GETLK, &file_lock);
-                if (error < 0)
-                        goto out;
-        } else
-                posix_test_lock(filp, &file_lock);
+        error = vfs_test_lock(filp, &file_lock);
+        if (error)
+                goto out;
  
         flock.l_type = file_lock.fl_type;
         if (file_lock.fl_type != F_UNLCK) {
@@ -1797,13 +1812,10 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
         if (error)
                 goto out;
 
-        if (filp->f_op && filp->f_op->lock) {
-                error = filp->f_op->lock(filp, F_GETLK, &file_lock);
-                if (error < 0)
-                        goto out;
-        } else
-                posix_test_lock(filp, &file_lock);
- 
+        error = vfs_test_lock(filp, &file_lock);
+        if (error)
+                goto out;
+
         flock.l_type = file_lock.fl_type;
         if (file_lock.fl_type != F_UNLCK)
                 posix_lock_to_flock64(&flock, &file_lock);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9e1ddffe3884..2a2a43988f50 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -856,6 +856,7 @@ extern int posix_lock_file_conf(struct file *, struct file_lock *, struct file_l
 extern int posix_lock_file(struct file *, struct file_lock *);
 extern int posix_lock_file_wait(struct file *, struct file_lock *);
 extern int posix_unblock_lock(struct file *, struct file_lock *);
+extern int vfs_test_lock(struct file *, struct file_lock *);
 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
 extern int __break_lease(struct inode *inode, unsigned int flags);
 extern void lease_get_mtime(struct inode *, struct timespec *time);