/*
* V9FS definitions.
*
* Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
#include <linux/backing-dev.h>
/**
* enum p9_session_flags - option flags for each 9P session
* @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions
* @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions
* @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
* @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
* @V9FS_ACCESS_ANY: use a single attach for all users
* @V9FS_ACCESS_MASK: bit mask of different ACCESS options
*
* Session flags reflect options selected by users at mount time
*/
enum p9_session_flags {
V9FS_PROTO_2000U = 0x01,
V9FS_PROTO_2000L = 0x02,
V9FS_ACCESS_SINGLE = 0x04,
V9FS_ACCESS_USER = 0x08,
V9FS_ACCESS_ANY = 0x0C,
V9FS_ACCESS_MASK = 0x0C,
};
/* possible values of ->cache */
/**
* enum p9_cache_modes - user specified cache preferences
* @CACHE_NONE: do not cache data, dentries, or directory contents (default)
* @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency
*
* eventually support loose, tight, time, session, default always none
*/
enum p9_cache_modes {
CACHE_NONE,
CACHE_LOOSE,
CACHE_FSCACHE,
};
/**
* struct v9fs_session_info - per-instance session information
* @flags: session options of type &p9_session_flags
* @nodev: set to 1 to disable device mapping
* @debug: debug level
* @afid: authentication handle
* @cache: cache mode of type &p9_cache_modes
* @cachetag: the tag of the cache associated with this session
* @fscache: session cookie associated with FS-Cache
* @options: copy of options string given by user
* @uname: string user name to mount hierarchy as
* @aname: mount specifier for remote hierarchy
* @maxdata: maximum data to be sent/recvd per protocol message
* @dfltuid: default numeric userid to mount hierarchy as
* @dfltgid: default numeric groupid to mount hierarchy as
* @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy
* @clnt: reference to 9P network client instantiated for this session
* @slist: reference to list of registered 9p sessions
*
* This structure holds state for each session instance established during
* a sys_mount() .
*
* Bugs: there seems to be a lot of state which could be condensed and/or
* removed.
*/
struct v9fs_session_info {
/* options */
unsigned char flags;
unsigned char nodev;
unsigned short debug;
unsigned int afid;
unsigned int cache;
#ifdef CONFIG_9P_FSCACHE
char *cachetag;
struct fscache_cookie *fscache;
#endif
char *uname; /* user name to mount as */
char *aname; /* name of remote hierarchy being mounted */
unsigned int maxdata; /* max data for client interface */
unsigned int dfltuid; /* default uid/muid for legacy support */
unsigned int dfltgid; /* default gid for legacy support */
u32 uid; /* if ACCESS_SINGLE, the uid that has access */
struct p9_client *clnt; /* 9p client */
struct list_head slist; /* list of sessions registered with v9fs */
struct backing_dev_info bdi;
struct rw_semaphore rename_sem;
};
struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *,
char *);
void v9fs_session_close(struct v9fs_session_info *v9ses);
void v9fs_session_cancel(struct v9fs_session_info *v9ses);
void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
#define V9FS_MAGIC 0x01021997
/* other default globals */
#define V9FS_PORT 564
#define V9FS_DEFUSER "nobody"
#define V9FS_DEFANAME ""
#define V9FS_DEFUID (-2)
#define V9FS_DEFGID (-2)
static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
{
return (inode->i_sb->s_fs_info);
}
static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
{
return v9ses->flags & V9FS_PROTO_2000U;
}
static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses)
{
return v9ses->flags & V9FS_PROTO_2000L;
}
