zfs/include/sys/zfs_ctldir.h

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (C) 2011 Lawrence Livermore National Security, LLC.
 * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
 * LLNL-CODE-403049.
 * Rewritten for Linux by:
 *   Rohan Puri <rohan.puri15@gmail.com>
 *   Brian Behlendorf <behlendorf1@llnl.gov>
 */

#ifndef	_ZFS_CTLDIR_H
#define	_ZFS_CTLDIR_H

#include <sys/vnode.h>
#include <sys/zfs_vfsops.h>
#include <sys/zfs_znode.h>

#define	ZFS_CTLDIR_NAME		".zfs"
#define	ZFS_SNAPDIR_NAME	"snapshot"
#define	ZFS_SHAREDIR_NAME	"shares"

#define	zfs_has_ctldir(zdp)	\
	((zdp)->z_id == ZTOZSB(zdp)->z_root && \
	(ZTOZSB(zdp)->z_ctldir != NULL))
#define	zfs_show_ctldir(zdp)	\
	(zfs_has_ctldir(zdp) && \
	(ZTOZSB(zdp)->z_show_ctldir))

typedef struct {
	char			*se_name;
	char			*se_path;
	struct inode		*se_inode;
	struct delayed_work	se_work;
	avl_node_t		se_node;
} zfs_snapentry_t;

/* zfsctl generic functions */
extern int snapentry_compare(const void *a, const void *b);
extern boolean_t zfsctl_is_node(struct inode *ip);
extern boolean_t zfsctl_is_snapdir(struct inode *ip);
extern void zfsctl_inode_inactive(struct inode *ip);
extern void zfsctl_inode_destroy(struct inode *ip);
extern int zfsctl_create(zfs_sb_t *zsb);
extern void zfsctl_destroy(zfs_sb_t *zsb);
extern struct inode *zfsctl_root(znode_t *zp);
extern int zfsctl_fid(struct inode *ip, fid_t *fidp);

/* zfsctl '.zfs' functions */
extern int zfsctl_root_lookup(struct inode *dip, char *name,
    struct inode **ipp, int flags, cred_t *cr, int *direntflags,
    pathname_t *realpnp);

/* zfsctl '.zfs/snapshot' functions */
extern int zfsctl_snapdir_lookup(struct inode *dip, char *name,
    struct inode **ipp, int flags, cred_t *cr, int *direntflags,
    pathname_t *realpnp);
extern int zfsctl_snapdir_rename(struct inode *sdip, char *sname,
    struct inode *tdip, char *tname, cred_t *cr, int flags);
extern int zfsctl_snapdir_remove(struct inode *dip, char *name, cred_t *cr,
    int flags);
extern int zfsctl_snapdir_mkdir(struct inode *dip, char *dirname, vattr_t *vap,
    struct inode **ipp, cred_t *cr, int flags);
extern void zfsctl_snapdir_inactive(struct inode *ip);
extern int zfsctl_unmount_snapshot(zfs_sb_t *zsb, char *name, int flags);
extern int zfsctl_unmount_snapshots(zfs_sb_t *zsb, int flags, int *count);
extern int zfsctl_mount_snapshot(struct path *path, int flags);
extern int zfsctl_lookup_objset(struct super_block *sb, uint64_t objsetid,
    zfs_sb_t **zsb);

/* zfsctl '.zfs/shares' functions */
extern int zfsctl_shares_lookup(struct inode *dip, char *name,
    struct inode **ipp, int flags, cred_t *cr, int *direntflags,
    pathname_t *realpnp);

/* zfsctl_init/fini functions */
extern void zfsctl_init(void);
extern void zfsctl_fini(void);

/*
 * These inodes numbers are reserved for the .zfs control directory.
 * It is important that they be no larger that 48-bits because only
 * 6 bytes are reserved in the NFS file handle for the object number.
 * However, they should be as large as possible to avoid conflicts
 * with the objects which are assigned monotonically by the dmu.
 */
#define	ZFSCTL_INO_ROOT		0x0000FFFFFFFFFFFFULL
#define	ZFSCTL_INO_SHARES	0x0000FFFFFFFFFFFEULL
#define	ZFSCTL_INO_SNAPDIR	0x0000FFFFFFFFFFFDULL
#define	ZFSCTL_INO_SNAPDIRS	0x0000FFFFFFFFFFFCULL

#define	ZFSCTL_EXPIRE_SNAPSHOT	300

#endif	/* _ZFS_CTLDIR_H */