eventfd: fold eventfd_ctx_get() into eventfd_ctx_fileget()

eventfd_ctx_get() is not used outside of eventfd.c, so unexport it and
fold it into eventfd_ctx_fileget().

(eventfd_ctx_get() was apparently added years ago for KVM irqfd's, but
was never used.)

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/eventfd.c

@@ -79,25 +79,12 @@ static void eventfd_free(struct kref *kref)
 	eventfd_free_ctx(ctx);
 }
 
-/**
- * eventfd_ctx_get - Acquires a reference to the internal eventfd context.
- * @ctx: [in] Pointer to the eventfd context.
- *
- * Returns: In case of success, returns a pointer to the eventfd context.
- */
-struct eventfd_ctx *eventfd_ctx_get(struct eventfd_ctx *ctx)
-{
-	kref_get(&ctx->kref);
-	return ctx;
-}
-EXPORT_SYMBOL_GPL(eventfd_ctx_get);
-
 /**
  * eventfd_ctx_put - Releases a reference to the internal eventfd context.
  * @ctx: [in] Pointer to eventfd context.
  *
  * The eventfd context reference must have been previously acquired either
- * with eventfd_ctx_get() or eventfd_ctx_fdget().
+ * with eventfd_ctx_fdget() or eventfd_ctx_fileget().
  */
 void eventfd_ctx_put(struct eventfd_ctx *ctx)
 {
@@ -382,10 +369,14 @@ EXPORT_SYMBOL_GPL(eventfd_ctx_fdget);
  */
 struct eventfd_ctx *eventfd_ctx_fileget(struct file *file)
 {
+	struct eventfd_ctx *ctx;
+
 	if (file->f_op != &eventfd_fops)
 		return ERR_PTR(-EINVAL);
 
-	return eventfd_ctx_get(file->private_data);
+	ctx = file->private_data;
+	kref_get(&ctx->kref);
+	return ctx;
 }
 EXPORT_SYMBOL_GPL(eventfd_ctx_fileget);
 

include/linux/eventfd.h

@@ -26,11 +26,11 @@
 #define EFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK)
 #define EFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS | EFD_SEMAPHORE)
 
+struct eventfd_ctx;
 struct file;
 
 #ifdef CONFIG_EVENTFD
 
-struct eventfd_ctx *eventfd_ctx_get(struct eventfd_ctx *ctx);
 void eventfd_ctx_put(struct eventfd_ctx *ctx);
 struct file *eventfd_fget(int fd);
 struct eventfd_ctx *eventfd_ctx_fdget(int fd);