[STABLE v5.15.y 1/8] file: add fput() cleanup helper

[Lee Jones]

From: Christian Brauner <brauner@xxxxxxxxxx>

[ Upstream commit 257b1c2c78c25643526609dee0c15f1544eb3252 ]

Add a simple helper to put a file reference.

Link: https://lore.kernel.org/r/20240719-work-mount-namespace-v1-4-834113cab0d2@xxxxxxxxxx
Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Wentao Guan <guanwentao@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
(cherry picked from commit ac275934626a85285cca43405e876566daa10533)
Signed-off-by: Lee Jones <lee@xxxxxxxxxx>
---
 include/linux/file.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/file.h b/include/linux/file.h
index 6726240b9279..fb8a5d22531e 100644
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -11,6 +11,7 @@
 #include <linux/posix_types.h>
 #include <linux/errno.h>
 #include <linux/cleanup.h>
+#include <linux/err.h>
 
 struct file;
 
@@ -95,6 +96,7 @@ extern void put_unused_fd(unsigned int fd);
 
 DEFINE_CLASS(get_unused_fd, int, if (_T >= 0) put_unused_fd(_T),
 	     get_unused_fd_flags(flags), unsigned flags)
+DEFINE_FREE(fput, struct file *, if (!IS_ERR_OR_NULL(_T)) fput(_T))
 
 extern void fd_install(unsigned int fd, struct file *file);
 
-- 
2.55.0.979.g7e5102b832-goog