v9fs.h

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/*
 * V9FS definitions.
 *
 *  Copyright (C) 2004-2008 by Eric Van Hensbergen <[email protected]>
 *  Copyright (C) 2002 by Ron Minnich <[email protected]>
 *
 *  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
 *
 */
#ifndef FS_9P_V9FS_H
#define FS_9P_V9FS_H

#include <linux/backing-dev.h>

#define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \
             V9FS_ACCESS_USER |   \
             V9FS_ACCESS_CLIENT)
#define V9FS_ACCESS_MASK V9FS_ACCESS_ANY
#define V9FS_ACL_MASK V9FS_POSIX_ACL

enum p9_session_flags {
    V9FS_PROTO_2000U    = 0x01,
    V9FS_PROTO_2000L    = 0x02,
    V9FS_ACCESS_SINGLE  = 0x04,
    V9FS_ACCESS_USER    = 0x08,
    V9FS_ACCESS_CLIENT  = 0x10,
    V9FS_POSIX_ACL      = 0x20
};

/* possible values of ->cache */
enum p9_cache_modes {
    CACHE_NONE,
    CACHE_LOOSE,
    CACHE_FSCACHE,
};

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;
};

/* cache_validity flags */
#define V9FS_INO_INVALID_ATTR 0x01

struct v9fs_inode {
#ifdef CONFIG_9P_FSCACHE
    spinlock_t fscache_lock;
    struct fscache_cookie *fscache;
#endif
    struct p9_qid qid;
    unsigned int cache_validity;
    struct p9_fid *writeback_fid;
    struct mutex v_mutex;
    struct inode vfs_inode;
};

static inline struct v9fs_inode *V9FS_I(const struct inode *inode)
{
    return container_of(inode, struct v9fs_inode, vfs_inode);
}

struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *,
                                    char *);
extern void v9fs_session_close(struct v9fs_session_info *v9ses);
extern void v9fs_session_cancel(struct v9fs_session_info *v9ses);
extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
            unsigned int flags);
extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d);
extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d);
extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
            struct inode *new_dir, struct dentry *new_dentry);
extern void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd,
            void *p);
extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses,
                     struct p9_fid *fid,
                     struct super_block *sb, int new);
extern const struct inode_operations v9fs_dir_inode_operations_dotl;
extern const struct inode_operations v9fs_file_inode_operations_dotl;
extern const struct inode_operations v9fs_symlink_inode_operations_dotl;
extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses,
                          struct p9_fid *fid,
                          struct super_block *sb, int new);

/* 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 struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry)
{
    return dentry->d_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;
}

static inline struct inode *
v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
            struct super_block *sb)
{
    if (v9fs_proto_dotl(v9ses))
        return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0);
    else
        return v9fs_inode_from_fid(v9ses, fid, sb, 0);
}

static inline struct inode *
v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
                struct super_block *sb)
{
    if (v9fs_proto_dotl(v9ses))
        return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1);
    else
        return v9fs_inode_from_fid(v9ses, fid, sb, 1);
}

#endif