[mirror_ubuntu-zesty-kernel.git] / fs / overlayfs / ovl_entry.h

/*
 *
 * Copyright (C) 2011 Novell Inc.
 * Copyright (C) 2016 Red Hat, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

struct ovl_config {
	char *lowerdir;
	char *upperdir;
	char *workdir;
	bool default_permissions;
	bool redirect_dir;
};

/* private information held for overlayfs's superblock */
struct ovl_fs {
	struct vfsmount *upper_mnt;
	unsigned numlower;
	struct vfsmount **lower_mnt;
	struct dentry *workdir;
	long namelen;
	/* pathnames of lower and upper dirs, for show_options */
	struct ovl_config config;
	/* creds of process who forced instantiation of super block */
	const struct cred *creator_cred;
};

/* private information held for every overlayfs dentry */
struct ovl_entry {
	struct dentry *__upperdentry;
	struct ovl_dir_cache *cache;
	union {
		struct {
			u64 version;
			const char *redirect;
			bool opaque;
		};
		struct rcu_head rcu;
	};
	unsigned numlower;
	struct path lowerstack[];
};

struct ovl_entry *ovl_alloc_entry(unsigned int numlower);

static inline struct dentry *ovl_upperdentry_dereference(struct ovl_entry *oe)
{
	return lockless_dereference(oe->__upperdentry);
}
Commit	Line	Data
bbb1e54d MS	1	/*
	2	*
	3	* Copyright (C) 2011 Novell Inc.
	4	* Copyright (C) 2016 Red Hat, Inc.
	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License version 2 as published by
	8	* the Free Software Foundation.
	9	*/
	10
	11	struct ovl_config {
	12	char *lowerdir;
	13	char *upperdir;
	14	char *workdir;
	15	bool default_permissions;
a6c60655	16	bool redirect_dir;
bbb1e54d MS	17	};
	18
	19	/* private information held for overlayfs's superblock */
	20	struct ovl_fs {
	21	struct vfsmount *upper_mnt;
	22	unsigned numlower;
	23	struct vfsmount **lower_mnt;
	24	struct dentry *workdir;
6b2d5fe4	25	long namelen;
bbb1e54d MS	26	/* pathnames of lower and upper dirs, for show_options */
	27	struct ovl_config config;
	28	/* creds of process who forced instantiation of super block */
	29	const struct cred *creator_cred;
	30	};
	31
	32	/* private information held for every overlayfs dentry */
	33	struct ovl_entry {
	34	struct dentry *__upperdentry;
	35	struct ovl_dir_cache *cache;
	36	union {
	37	struct {
	38	u64 version;
02b69b28	39	const char *redirect;
bbb1e54d MS	40	bool opaque;
	41	};
	42	struct rcu_head rcu;
	43	};
	44	unsigned numlower;
	45	struct path lowerstack[];
	46	};
	47
	48	struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
	49
	50	static inline struct dentry ovl_upperdentry_dereference(struct ovl_entry oe)
	51	{
	52	return lockless_dereference(oe->__upperdentry);
	53	}