Esempio n. 1
0
/*
 * returns the number of lower positive dentries,
 * otherwise an error.
 * can be called at unlinking with @type is zero.
 */
int au_lkup_dentry(struct dentry *dentry, aufs_bindex_t bstart, mode_t type,
		   struct nameidata *nd)
{
	int npositive, err;
	aufs_bindex_t bindex, btail, bdiropq;
	unsigned char isdir;
	struct qstr whname;
	struct au_do_lookup_args args = {
		.flags	= 0,
		.type	= type,
		.nd	= nd
	};
	const struct qstr *name = &dentry->d_name;
	struct dentry *parent;
	struct inode *inode;

	err = au_test_shwh(dentry->d_sb, name);
	if (unlikely(err))
		goto out;

	err = au_wh_name_alloc(&whname, name);
	if (unlikely(err))
		goto out;

	inode = dentry->d_inode;
	isdir = !!(inode && S_ISDIR(inode->i_mode));
	if (!type)
		au_fset_lkup(args.flags, ALLOW_NEG);

	npositive = 0;
	parent = dget_parent(dentry);
	btail = au_dbtaildir(parent);
	for (bindex = bstart; bindex <= btail; bindex++) {
		struct dentry *h_parent, *h_dentry;
		struct inode *h_inode, *h_dir;

		h_dentry = au_h_dptr(dentry, bindex);
		if (h_dentry) {
			if (h_dentry->d_inode)
				npositive++;
			if (type != S_IFDIR)
				break;
			continue;
		}
		h_parent = au_h_dptr(parent, bindex);
		if (!h_parent)
			continue;
		h_dir = h_parent->d_inode;
		if (!h_dir || !S_ISDIR(h_dir->i_mode))
			continue;

		mutex_lock_nested(&h_dir->i_mutex, AuLsc_I_PARENT);
		h_dentry = au_do_lookup(h_parent, dentry, bindex, &whname,
					&args);
		mutex_unlock(&h_dir->i_mutex);
		err = PTR_ERR(h_dentry);
		if (IS_ERR(h_dentry))
			goto out_parent;
		au_fclr_lkup(args.flags, ALLOW_NEG);

		if (au_dbwh(dentry) >= 0)
			break;
		if (!h_dentry)
			continue;
		h_inode = h_dentry->d_inode;
		if (!h_inode)
			continue;
		npositive++;
		if (!args.type)
			args.type = h_inode->i_mode & S_IFMT;
		if (args.type != S_IFDIR)
			break;
		else if (isdir) {
			/* the type of lower may be different */
			bdiropq = au_dbdiropq(dentry);
			if (bdiropq >= 0 && bdiropq <= bindex)
				break;
		}
	}

	if (npositive) {
		AuLabel(positive);
		au_update_dbstart(dentry);
	}
	err = npositive;
	if (unlikely(!au_opt_test(au_mntflags(dentry->d_sb), UDBA_NONE)
		     && au_dbstart(dentry) < 0)) {
		err = -EIO;
		AuIOErr("both of real entry and whiteout found, %.*s, err %d\n",
			AuDLNPair(dentry), err);
	}

out_parent:
	dput(parent);
	kfree(whname.name);
out:
	return err;
}

struct dentry *au_sio_lkup_one(struct qstr *name, struct dentry *parent,
			       struct au_branch *br)
{
	struct dentry *dentry;
	int wkq_err;

	if (!au_test_h_perm_sio(parent->d_inode, MAY_EXEC))
		dentry = au_lkup_one(name, parent, br, /*nd*/NULL);
	else {
		struct au_lkup_one_args args = {
			.errp		= &dentry,
			.name		= name,
			.h_parent	= parent,
			.br		= br,
			.nd		= NULL
		};

		wkq_err = au_wkq_wait(au_call_lkup_one, &args);
		if (unlikely(wkq_err))
			dentry = ERR_PTR(wkq_err);
	}

	return dentry;
}

/*
 * lookup @dentry on @bindex which should be negative.
 */
int au_lkup_neg(struct dentry *dentry, aufs_bindex_t bindex)
{
	int err;
	struct dentry *parent, *h_parent, *h_dentry;

	parent = dget_parent(dentry);
	h_parent = au_h_dptr(parent, bindex);
	h_dentry = au_sio_lkup_one(&dentry->d_name, h_parent,
				   au_sbr(dentry->d_sb, bindex));
	err = PTR_ERR(h_dentry);
	if (IS_ERR(h_dentry))
		goto out;
	if (unlikely(h_dentry->d_inode)) {
		err = -EIO;
		AuIOErr("%.*s should be negative on b%d.\n",
			AuDLNPair(h_dentry), bindex);
		dput(h_dentry);
		goto out;
	}

	err = 0;
	if (bindex < au_dbstart(dentry))
		au_set_dbstart(dentry, bindex);
	if (au_dbend(dentry) < bindex)
		au_set_dbend(dentry, bindex);
	au_set_h_dptr(dentry, bindex, h_dentry);

out:
	dput(parent);
	return err;
}
Esempio n. 2
0
/*
 * returns the number of lower positive dentries,
 * otherwise an error.
 * can be called at unlinking with @type is zero.
 */
int au_lkup_dentry(struct dentry *dentry, aufs_bindex_t bstart, mode_t type)
{
	int npositive, err;
	aufs_bindex_t bindex, btail, bdiropq;
	unsigned char isdir, dirperm1;
	struct qstr whname;
	struct au_do_lookup_args args = {
		.flags		= 0,
		.type		= type
	};
	const struct qstr *name = &dentry->d_name;
	struct dentry *parent;
	struct super_block *sb;

	sb = dentry->d_sb;
	err = au_test_shwh(sb, name);
	if (unlikely(err))
		goto out;

	err = au_wh_name_alloc(&whname, name);
	if (unlikely(err))
		goto out;

	isdir = !!d_is_dir(dentry);
	if (!type)
		au_fset_lkup(args.flags, ALLOW_NEG);
	dirperm1 = !!au_opt_test(au_mntflags(sb), DIRPERM1);

	npositive = 0;
	parent = dget_parent(dentry);
	btail = au_dbtaildir(parent);
	for (bindex = bstart; bindex <= btail; bindex++) {
		struct dentry *h_parent, *h_dentry;
		struct inode *h_inode, *h_dir;

		h_dentry = au_h_dptr(dentry, bindex);
		if (h_dentry) {
			if (d_is_positive(h_dentry))
				npositive++;
			if (type != S_IFDIR)
				break;
			continue;
		}
		h_parent = au_h_dptr(parent, bindex);
		if (!h_parent || !d_is_dir(h_parent))
			continue;

		h_dir = d_inode(h_parent);
		mutex_lock_nested(&h_dir->i_mutex, AuLsc_I_PARENT);
		h_dentry = au_do_lookup(h_parent, dentry, bindex, &whname,
					&args);
		mutex_unlock(&h_dir->i_mutex);
		err = PTR_ERR(h_dentry);
		if (IS_ERR(h_dentry))
			goto out_parent;
		if (h_dentry)
			au_fclr_lkup(args.flags, ALLOW_NEG);
		if (dirperm1)
			au_fset_lkup(args.flags, IGNORE_PERM);

		if (au_dbwh(dentry) >= 0)
			break;
		if (!h_dentry)
			continue;
		if (d_is_negative(h_dentry))
			continue;
		h_inode = d_inode(h_dentry);
		npositive++;
		if (!args.type)
			args.type = h_inode->i_mode & S_IFMT;
		if (args.type != S_IFDIR)
			break;
		else if (isdir) {
			/* the type of lower may be different */
			bdiropq = au_dbdiropq(dentry);
			if (bdiropq >= 0 && bdiropq <= bindex)
				break;
		}
	}

	if (npositive) {
		AuLabel(positive);
		au_update_dbstart(dentry);
	}
	err = npositive;
	if (unlikely(!au_opt_test(au_mntflags(sb), UDBA_NONE)
		     && au_dbstart(dentry) < 0)) {
		err = -EIO;
		AuIOErr("both of real entry and whiteout found, %pd, err %d\n",
			dentry, err);
	}

out_parent:
	dput(parent);
	kfree(whname.name);
out:
	return err;
}

struct dentry *au_sio_lkup_one(struct qstr *name, struct dentry *parent)
{
	struct dentry *dentry;
	int wkq_err;

	if (!au_test_h_perm_sio(d_inode(parent), MAY_EXEC))
		dentry = vfsub_lkup_one(name, parent);
	else {
		struct vfsub_lkup_one_args args = {
			.errp	= &dentry,
			.name	= name,
			.parent	= parent
		};

		wkq_err = au_wkq_wait(vfsub_call_lkup_one, &args);
		if (unlikely(wkq_err))
			dentry = ERR_PTR(wkq_err);
	}

	return dentry;
}

/*
 * lookup @dentry on @bindex which should be negative.
 */
int au_lkup_neg(struct dentry *dentry, aufs_bindex_t bindex, int wh)
{
	int err;
	struct dentry *parent, *h_parent, *h_dentry;
	struct au_branch *br;

	parent = dget_parent(dentry);
	h_parent = au_h_dptr(parent, bindex);
	br = au_sbr(dentry->d_sb, bindex);
	if (wh)
		h_dentry = au_whtmp_lkup(h_parent, br, &dentry->d_name);
	else
		h_dentry = au_sio_lkup_one(&dentry->d_name, h_parent);
	err = PTR_ERR(h_dentry);
	if (IS_ERR(h_dentry))
		goto out;
	if (unlikely(d_is_positive(h_dentry))) {
		err = -EIO;
		AuIOErr("%pd should be negative on b%d.\n", h_dentry, bindex);
		dput(h_dentry);
		goto out;
	}

	err = 0;
	if (bindex < au_dbstart(dentry))
		au_set_dbstart(dentry, bindex);
	if (au_dbend(dentry) < bindex)
		au_set_dbend(dentry, bindex);
	au_set_h_dptr(dentry, bindex, h_dentry);

out:
	dput(parent);
	return err;
}