Commit 370e55ac authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

ovl: rename: simplify handling of lower/merged directory 



d_is_dir() is safe to call on a negative dentry.  Use this fact to simplify
handling of the lower or merged directories.

Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 38e813db

fs/overlayfs/dir.c

+12 −18
Original line number Diff line number Diff line
@@ -761,13 +761,18 @@ static int ovl_rmdir(struct inode *dir, struct dentry *dentry) 
	return ovl_do_remove(dentry, true);

}



static bool ovl_type_merge_or_lower(struct dentry *dentry)

{

	enum ovl_path_type type = ovl_path_type(dentry);



	return OVL_TYPE_MERGE(type) || !OVL_TYPE_UPPER(type);

}



static int ovl_rename(struct inode *olddir, struct dentry *old,

		      struct inode *newdir, struct dentry *new,

		      unsigned int flags)

{

	int err;

	enum ovl_path_type old_type;

	enum ovl_path_type new_type;

	struct dentry *old_upperdir;

	struct dentry *new_upperdir;

	struct dentry *olddentry;
@@ -778,7 +783,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, 
	bool cleanup_whiteout = false;

	bool overwrite = !(flags & RENAME_EXCHANGE);

	bool is_dir = d_is_dir(old);

	bool new_is_dir = false;

	bool new_is_dir = d_is_dir(new);

	struct dentry *opaquedir = NULL;

	const struct cred *old_cred = NULL;
@@ -789,22 +794,11 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, 
	flags &= ~RENAME_NOREPLACE;



	/* Don't copy up directory trees */

	old_type = ovl_path_type(old);

	err = -EXDEV;

	if (OVL_TYPE_MERGE_OR_LOWER(old_type) && is_dir)

	if (is_dir && ovl_type_merge_or_lower(old))

		goto out;



	if (new->d_inode) {

		if (d_is_dir(new))

			new_is_dir = true;



		new_type = ovl_path_type(new);

		err = -EXDEV;

		if (!overwrite && OVL_TYPE_MERGE_OR_LOWER(new_type) && new_is_dir)

	if (!overwrite && new_is_dir && ovl_type_merge_or_lower(new))

		goto out;

	} else {

		new_type = __OVL_PATH_UPPER;

	}



	err = ovl_want_write(old);

	if (err)
@@ -828,7 +822,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, 


	old_cred = ovl_override_creds(old->d_sb);



	if (overwrite && OVL_TYPE_MERGE_OR_LOWER(new_type) && new_is_dir) {

	if (overwrite && new_is_dir && ovl_type_merge_or_lower(new)) {

		opaquedir = ovl_check_empty_and_clear(new);

		err = PTR_ERR(opaquedir);

		if (IS_ERR(opaquedir)) {

fs/overlayfs/overlayfs.h

+0 −3
Original line number Diff line number Diff line
@@ -18,9 +18,6 @@ enum ovl_path_type { 


#define OVL_TYPE_UPPER(type)	((type) & __OVL_PATH_UPPER)

#define OVL_TYPE_MERGE(type)	((type) & __OVL_PATH_MERGE)

#define OVL_TYPE_MERGE_OR_LOWER(type) \

	(OVL_TYPE_MERGE(type) || !OVL_TYPE_UPPER(type))





#define OVL_XATTR_PREFIX XATTR_TRUSTED_PREFIX "overlay."

#define OVL_XATTR_OPAQUE OVL_XATTR_PREFIX "opaque"