From: Lorenz Bauer <lmb@cloudflare.com>
Date: Thu, 28 Oct 2021 10:47:21 +0100
Subject: libfs: Move shmem_exchange to simple_rename_exchange
Patch-mainline: v5.16-rc1
Git-commit: 6429e46304ac7820eebbea2bf5d73b90c18e0e06
References: jsc#PED-1377
Move shmem_exchange and make it available to other callers.
Suggested-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/bpf/20211028094724.59043-2-lmb@cloudflare.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
fs/libfs.c | 24 ++++++++++++++++++++++++
include/linux/fs.h | 2 ++
mm/shmem.c | 24 +-----------------------
3 files changed, 27 insertions(+), 23 deletions(-)
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -448,6 +448,30 @@ int simple_rmdir(struct inode *dir, stru
}
EXPORT_SYMBOL(simple_rmdir);
+int simple_rename_exchange(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ bool old_is_dir = d_is_dir(old_dentry);
+ bool new_is_dir = d_is_dir(new_dentry);
+
+ if (old_dir != new_dir && old_is_dir != new_is_dir) {
+ if (old_is_dir) {
+ drop_nlink(old_dir);
+ inc_nlink(new_dir);
+ } else {
+ drop_nlink(new_dir);
+ inc_nlink(old_dir);
+ }
+ }
+ old_dir->i_ctime = old_dir->i_mtime =
+ new_dir->i_ctime = new_dir->i_mtime =
+ d_inode(old_dentry)->i_ctime =
+ d_inode(new_dentry)->i_ctime = current_time(old_dir);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(simple_rename_exchange);
+
int simple_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
struct dentry *old_dentry, struct inode *new_dir,
struct dentry *new_dentry, unsigned int flags)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3455,6 +3455,8 @@ extern int simple_open(struct inode *ino
extern int simple_link(struct dentry *, struct inode *, struct dentry *);
extern int simple_unlink(struct inode *, struct dentry *);
extern int simple_rmdir(struct inode *, struct dentry *);
+extern int simple_rename_exchange(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry);
extern int simple_rename(struct user_namespace *, struct inode *,
struct dentry *, struct inode *, struct dentry *,
unsigned int);
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2960,28 +2960,6 @@ static int shmem_rmdir(struct inode *dir
return shmem_unlink(dir, dentry);
}
-static int shmem_exchange(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry)
-{
- bool old_is_dir = d_is_dir(old_dentry);
- bool new_is_dir = d_is_dir(new_dentry);
-
- if (old_dir != new_dir && old_is_dir != new_is_dir) {
- if (old_is_dir) {
- drop_nlink(old_dir);
- inc_nlink(new_dir);
- } else {
- drop_nlink(new_dir);
- inc_nlink(old_dir);
- }
- }
- old_dir->i_ctime = old_dir->i_mtime =
- new_dir->i_ctime = new_dir->i_mtime =
- d_inode(old_dentry)->i_ctime =
- d_inode(new_dentry)->i_ctime = current_time(old_dir);
-
- return 0;
-}
-
static int shmem_whiteout(struct user_namespace *mnt_userns,
struct inode *old_dir, struct dentry *old_dentry)
{
@@ -3027,7 +3005,7 @@ static int shmem_rename2(struct user_nam
return -EINVAL;
if (flags & RENAME_EXCHANGE)
- return shmem_exchange(old_dir, old_dentry, new_dir, new_dentry);
+ return simple_rename_exchange(old_dir, old_dentry, new_dir, new_dentry);
if (!simple_empty(new_dentry))
return -ENOTEMPTY;