root/fs/9p/v9fs.h

INCLUDED FROM

DEFINITIONS

1. v9fs_inode2v9ses
2. v9fs_extended

/*
 * 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
 *
 */

/**
 * enum p9_session_flags - option flags for each 9P session
 * @V9FS_EXTENDED: whether or not to use 9P2000.u 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_EXTENDED           = 0x01,
        V9FS_ACCESS_SINGLE      = 0x02,
        V9FS_ACCESS_USER        = 0x04,
        V9FS_ACCESS_ANY         = 0x06,
        V9FS_ACCESS_MASK        = 0x06,
};

/* 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,
};

/**
 * 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
 * @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
 * @debugfs_dir: reference to debugfs_dir which can be used for add'l debug
 *
 * 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;

        char *options;          /* copy of mount options */
        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 dentry *debugfs_dir;
};

extern struct dentry *v9fs_debugfs_root;

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);

#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_extended(struct v9fs_session_info *v9ses)
{
        return v9ses->flags & V9FS_EXTENDED;
}