vfs_inode.c

		goto FreeFcall;
	}

	if (!fcall)
		return -EIO;

	if (!(fcall->params.rstat.stat.mode & V9FS_DMSYMLINK)) {
		retval = -EINVAL;
		goto FreeFcall;
	}

	/* copy extension buffer into buffer */
	if (fcall->params.rstat.stat.extension.len < buflen)
		buflen = fcall->params.rstat.stat.extension.len;

	memcpy(buffer, fcall->params.rstat.stat.extension.str, buflen - 1);
	buffer[buflen-1] = 0;

	retval = buflen;

      FreeFcall:
	kfree(fcall);

	return retval;
}

/**
 * v9fs_vfs_readlink - read a symlink's location
 * @dentry: dentry for symlink
 * @buf: buffer to load symlink location into
 * @buflen: length of buffer
 *
 */

static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer,
			     int buflen)
{
	int retval;
	int ret;
	char *link = __getname();

	if (buflen > PATH_MAX)
		buflen = PATH_MAX;

	dprintk(DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry);

	retval = v9fs_readlink(dentry, link, buflen);

	if (retval > 0) {
		if ((ret = copy_to_user(buffer, link, retval)) != 0) {
			dprintk(DEBUG_ERROR, "problem copying to user: %d\n",
				ret);
			retval = ret;
		}
	}

	__putname(link);
	return retval;
}

/**
 * v9fs_vfs_follow_link - follow a symlink path
 * @dentry: dentry for symlink
 * @nd: nameidata
 *
 */

static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
{
	int len = 0;
	char *link = __getname();

	dprintk(DEBUG_VFS, "%s n", dentry->d_name.name);

	if (!link)
		link = ERR_PTR(-ENOMEM);
	else {
		len = v9fs_readlink(dentry, link, strlen(link));

		if (len < 0) {
			__putname(link);
			link = ERR_PTR(len);
		} else
			link[len] = 0;
	}
	nd_set_link(nd, link);

	return NULL;
}

/**
 * v9fs_vfs_put_link - release a symlink path
 * @dentry: dentry for symlink
 * @nd: nameidata
 *
 */

static void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
{
	char *s = nd_get_link(nd);

	dprintk(DEBUG_VFS, " %s %s\n", dentry->d_name.name, s);
	if (!IS_ERR(s))
		__putname(s);
}

static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
	int mode, const char *extension)
{
	int err;
	u32 fid, perm;
	struct v9fs_session_info *v9ses;
	struct v9fs_fid *dfid, *vfid;
	struct inode *inode;
	struct v9fs_fcall *fcall;
	struct v9fs_wstat wstat;

	fcall = NULL;
	inode = NULL;
	vfid = NULL;
	v9ses = v9fs_inode2v9ses(dir);
	dfid = v9fs_fid_lookup(dentry->d_parent);
	perm = unixmode2p9mode(v9ses, mode);

	if (!v9ses->extended) {
		dprintk(DEBUG_ERROR, "not extended\n");
		return -EPERM;
	}

	err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
		perm, V9FS_OREAD, &fid, NULL, NULL);

	if (err)
		goto error;

	err = v9fs_t_clunk(v9ses, fid);
	if (err)
		goto error;

	vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
	if (IS_ERR(vfid)) {
		err = PTR_ERR(vfid);
		vfid = NULL;
		goto error;
	}

	inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
	if (IS_ERR(inode)) {
		err = PTR_ERR(inode);
		inode = NULL;
		goto error;
	}

	/* issue a Twstat */
	v9fs_blank_wstat(&wstat);
	wstat.muid = v9ses->name;
	wstat.extension = (char *) extension;
	err = v9fs_t_wstat(v9ses, vfid->fid, &wstat, &fcall);
	if (err < 0) {
		PRINT_FCALL_ERROR("wstat error", fcall);
		goto error;
	}

	kfree(fcall);
	dentry->d_op = &v9fs_dentry_operations;
	d_instantiate(dentry, inode);
	return 0;

error:
	kfree(fcall);
	if (vfid)
		v9fs_fid_destroy(vfid);

	if (inode)
		iput(inode);

	return err;

}

/**
 * v9fs_vfs_symlink - helper function to create symlinks
 * @dir: directory inode containing symlink
 * @dentry: dentry for symlink
 * @symname: symlink data
 *
 * See 9P2000.u RFC for more information
 *
 */

static int
v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
{
	dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
		symname);

	return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
}

/**
 * v9fs_vfs_link - create a hardlink
 * @old_dentry: dentry for file to link to
 * @dir: inode destination for new link
 * @dentry: dentry for link
 *
 */

/* XXX - lots of code dup'd from symlink and creates,
 * figure out a better reuse strategy
 */

static int
v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
	      struct dentry *dentry)
{
	int retval;
	struct v9fs_fid *oldfid;
	char *name;

	dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
		old_dentry->d_name.name);

	oldfid = v9fs_fid_lookup(old_dentry);
	if (!oldfid) {
		dprintk(DEBUG_ERROR, "can't find oldfid\n");
		return -EPERM;
	}

	name = __getname();
	sprintf(name, "hardlink(%d)\n", oldfid->fid);
	retval = v9fs_vfs_mkspecial(dir, dentry, V9FS_DMLINK, name);
	__putname(name);

	return retval;
}

/**
 * v9fs_vfs_mknod - create a special file
 * @dir: inode destination for new link
 * @dentry: dentry for file
 * @mode: mode for creation
 * @dev_t: device associated with special file
 *
 */

static int
v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
{
	int retval;
	char *name;

	dprintk(DEBUG_VFS, " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
		dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));

	if (!new_valid_dev(rdev))
		return -EINVAL;

	name = __getname();
	/* build extension */
	if (S_ISBLK(mode))
		sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
	else if (S_ISCHR(mode))
		sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
	else if (S_ISFIFO(mode))
		*name = 0;
	else {
		__putname(name);
		return -EINVAL;
	}

	retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
	__putname(name);

	return retval;
}

static struct inode_operations v9fs_dir_inode_operations_ext = {
	.create = v9fs_vfs_create,
	.lookup = v9fs_vfs_lookup,
	.symlink = v9fs_vfs_symlink,
	.link = v9fs_vfs_link,
	.unlink = v9fs_vfs_unlink,
	.mkdir = v9fs_vfs_mkdir,
	.rmdir = v9fs_vfs_rmdir,
	.mknod = v9fs_vfs_mknod,
	.rename = v9fs_vfs_rename,
	.readlink = v9fs_vfs_readlink,
	.getattr = v9fs_vfs_getattr,
	.setattr = v9fs_vfs_setattr,
};

static struct inode_operations v9fs_dir_inode_operations = {
	.create = v9fs_vfs_create,
	.lookup = v9fs_vfs_lookup,
	.unlink = v9fs_vfs_unlink,
	.mkdir = v9fs_vfs_mkdir,
	.rmdir = v9fs_vfs_rmdir,
	.mknod = v9fs_vfs_mknod,
	.rename = v9fs_vfs_rename,
	.getattr = v9fs_vfs_getattr,
	.setattr = v9fs_vfs_setattr,
};

static struct inode_operations v9fs_file_inode_operations = {
	.getattr = v9fs_vfs_getattr,
	.setattr = v9fs_vfs_setattr,
};

static struct inode_operations v9fs_symlink_inode_operations = {
	.readlink = v9fs_vfs_readlink,
	.follow_link = v9fs_vfs_follow_link,
	.put_link = v9fs_vfs_put_link,
	.getattr = v9fs_vfs_getattr,
	.setattr = v9fs_vfs_setattr,
};