Commit 42f269b9 authored by Amir Goldstein's avatar Amir Goldstein Committed by Miklos Szeredi
Browse files

ovl: rearrange code in ovl_copy_up_locked() 



As preparation to implementing copy up with O_TMPFILE,
name the variable for dentry before final rename 'temp' and
assign it to 'newdentry' only after rename.

Also lookup upper dentry before looking up temp dentry and
move ovl_set_timestamps() into ovl_copy_up_locked(), because
that is going to be more convenient for upcoming change.

Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent e7f52429

fs/overlayfs/copy_up.c

+25 −24
Original line number Original line Diff line number Diff line
@@ -232,12 +232,14 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat) 




static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir,

static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir,

			      struct dentry *dentry, struct path *lowerpath,

			      struct dentry *dentry, struct path *lowerpath,

			      struct kstat *stat, const char *link)

			      struct kstat *stat, const char *link,

			      struct kstat *pstat)

{

{

	struct inode *wdir = workdir->d_inode;

	struct inode *wdir = workdir->d_inode;

	struct inode *udir = upperdir->d_inode;

	struct inode *udir = upperdir->d_inode;

	struct dentry *newdentry = NULL;

	struct dentry *newdentry = NULL;

	struct dentry *upper = NULL;

	struct dentry *upper = NULL;

	struct dentry *temp = NULL;

	int err;

	int err;

	const struct cred *old_creds = NULL;

	const struct cred *old_creds = NULL;

	struct cred *new_creds = NULL;

	struct cred *new_creds = NULL;
@@ -248,25 +250,25 @@ static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir, 
		.link = link

		.link = link

	};

	};





	newdentry = ovl_lookup_temp(workdir, dentry);

	err = PTR_ERR(newdentry);

	if (IS_ERR(newdentry))

		goto out;



	upper = lookup_one_len(dentry->d_name.name, upperdir,

	upper = lookup_one_len(dentry->d_name.name, upperdir,

			       dentry->d_name.len);

			       dentry->d_name.len);

	err = PTR_ERR(upper);

	err = PTR_ERR(upper);

	if (IS_ERR(upper))

	if (IS_ERR(upper))

		goto out1;

		goto out;





	err = security_inode_copy_up(dentry, &new_creds);

	err = security_inode_copy_up(dentry, &new_creds);

	if (err < 0)

	if (err < 0)

		goto out2;

		goto out1;





	if (new_creds)

	if (new_creds)

		old_creds = override_creds(new_creds);

		old_creds = override_creds(new_creds);





	err = ovl_create_real(wdir, newdentry, &cattr, NULL, true);

	temp = ovl_lookup_temp(workdir, dentry);

	err = PTR_ERR(temp);

	if (IS_ERR(temp))

		goto out1;



	err = ovl_create_real(wdir, temp, &cattr, NULL, true);





	if (new_creds) {

	if (new_creds) {

		revert_creds(old_creds);

		revert_creds(old_creds);
@@ -281,39 +283,42 @@ static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir, 




		ovl_path_upper(dentry, &upperpath);

		ovl_path_upper(dentry, &upperpath);

		BUG_ON(upperpath.dentry != NULL);

		BUG_ON(upperpath.dentry != NULL);

		upperpath.dentry = newdentry;

		upperpath.dentry = temp;





		err = ovl_copy_up_data(lowerpath, &upperpath, stat->size);

		err = ovl_copy_up_data(lowerpath, &upperpath, stat->size);

		if (err)

		if (err)

			goto out_cleanup;

			goto out_cleanup;

	}

	}





	err = ovl_copy_xattr(lowerpath->dentry, newdentry);

	err = ovl_copy_xattr(lowerpath->dentry, temp);

	if (err)

	if (err)

		goto out_cleanup;

		goto out_cleanup;





	inode_lock(newdentry->d_inode);

	inode_lock(temp->d_inode);

	err = ovl_set_attr(newdentry, stat);

	err = ovl_set_attr(temp, stat);

	inode_unlock(newdentry->d_inode);

	inode_unlock(temp->d_inode);

	if (err)

	if (err)

		goto out_cleanup;

		goto out_cleanup;





	err = ovl_do_rename(wdir, newdentry, udir, upper, 0);

	err = ovl_do_rename(wdir, temp, udir, upper, 0);

	if (err)

	if (err)

		goto out_cleanup;

		goto out_cleanup;





	newdentry = dget(temp);

	ovl_dentry_update(dentry, newdentry);

	ovl_dentry_update(dentry, newdentry);

	ovl_inode_update(d_inode(dentry), d_inode(newdentry));

	ovl_inode_update(d_inode(dentry), d_inode(newdentry));

	newdentry = NULL;



	/* Restore timestamps on parent (best effort) */

	ovl_set_timestamps(upperdir, pstat);

out2:

out2:

	dput(upper);

	dput(temp);

out1:

out1:

	dput(newdentry);

	dput(upper);

out:

out:

	return err;

	return err;





out_cleanup:

out_cleanup:

	ovl_cleanup(wdir, newdentry);

	ovl_cleanup(wdir, temp);

	goto out2;

	goto out2;

}

}
@@ -368,11 +373,7 @@ static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, 
	}

	}





	err = ovl_copy_up_locked(workdir, upperdir, dentry, lowerpath,

	err = ovl_copy_up_locked(workdir, upperdir, dentry, lowerpath,

				 stat, link);

				 stat, link, &pstat);

	if (!err) {

		/* Restore timestamps on parent (best effort) */

		ovl_set_timestamps(upperdir, &pstat);

	}

out_unlock:

out_unlock:

	unlock_rename(workdir, upperdir);

	unlock_rename(workdir, upperdir);

	do_delayed_call(&done);

	do_delayed_call(&done);

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