Commit 6429e463 authored by Lorenz Bauer's avatar Lorenz Bauer Committed by Daniel Borkmann
Browse files

libfs: Move shmem_exchange to simple_rename_exchange 



Move shmem_exchange and make it available to other callers.

Suggested-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
Signed-off-by: default avatarLorenz Bauer <lmb@cloudflare.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarMiklos 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
parent 92f62485

fs/libfs.c

+24 −0
Original line number Diff line number Diff line
@@ -448,6 +448,30 @@ int simple_rmdir(struct inode *dir, struct dentry *dentry) 
}

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)

include/linux/fs.h

+2 −0
Original line number Diff line number Diff line
@@ -3383,6 +3383,8 @@ extern int simple_open(struct inode *inode, struct file *file); 
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);

mm/shmem.c

+1 −23
Original line number Diff line number Diff line
@@ -2947,28 +2947,6 @@ static int shmem_rmdir(struct inode *dir, struct dentry *dentry) 
	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)

{
@@ -3014,7 +2992,7 @@ static int shmem_rename2(struct user_namespace *mnt_userns, 
		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;