path: root/net/9p/client.c

/*
 * net/9p/clnt.c
 *
 * 9P Client
 *
 *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
 *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
 *
 *  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/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/poll.h>
#include <linux/idr.h>
#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <net/9p/9p.h>
#include <linux/parser.h>
#include <net/9p/transport.h>
#include <net/9p/client.h>

static struct p9_fid *p9_fid_create(struct p9_client *clnt);
static void p9_fid_destroy(struct p9_fid *fid);
static struct p9_stat *p9_clone_stat(struct p9_stat *st, int dotu);

/*
  * Client Option Parsing (code inspired by NFS code)
  *  - a little lazy - parse all client options
  */

enum {
	Opt_msize,
	Opt_trans,
	Opt_legacy,
	Opt_err,
};

static const match_table_t tokens = {
	{Opt_msize, "msize=%u"},
	{Opt_legacy, "noextend"},
	{Opt_trans, "trans=%s"},
	{Opt_err, NULL},
};

/**
 * v9fs_parse_options - parse mount options into session structure
 * @options: options string passed from mount
 * @v9ses: existing v9fs session information
 *
 * Return 0 upon success, -ERRNO upon failure
 */

static int parse_opts(char *opts, struct p9_client *clnt)
{
	char *options;
	char *p;
	substring_t args[MAX_OPT_ARGS];
	int option;
	int ret = 0;

	clnt->dotu = 1;
	clnt->msize = 8192;

	if (!opts)
		return 0;

	options = kstrdup(opts, GFP_KERNEL);
	if (!options) {
		P9_DPRINTK(P9_DEBUG_ERROR,
				"failed to allocate copy of option string\n");
		return -ENOMEM;
	}

	while ((p = strsep(&options, ",")) != NULL) {
		int token;
		if (!*p)
			continue;
		token = match_token(p, tokens, args);
		if (token < Opt_trans) {
			int r = match_int(&args[0], &option);
			if (r < 0) {
				P9_DPRINTK(P9_DEBUG_ERROR,
					"integer field, but no integer?\n");
				ret = r;
				continue;
			}
		}
		switch (token) {
		case Opt_msize:
			clnt->msize = option;
			break;
		case Opt_trans:
			clnt->trans_mod = v9fs_get_trans_by_name(&args[0]);
			break;
		case Opt_legacy:
			clnt->dotu = 0;
			break;
		default:
			continue;
		}
	}

	if (!clnt->trans_mod)
		clnt->trans_mod = v9fs_get_default_trans();

	kfree(options);
	return ret;
}


/**
 * p9_client_rpc - sends 9P request and waits until a response is available.
 *      The function can be interrupted.
 * @c: client data
 * @tc: request to be sent
 * @rc: pointer where a pointer to the response is stored
 */
int
p9_client_rpc(struct p9_client *c, struct p9_fcall *tc,
	struct p9_fcall **rc)
{
	return c->trans->rpc(c->trans, tc, rc);
}

struct p9_client *p9_client_create(const char *dev_name, char *options)
{
	int err, n;
	struct p9_client *clnt;
	struct p9_fcall *tc, *rc;
	struct p9_str *version;

	err = 0;
	tc = NULL;
	rc = NULL;
	clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
	if (!clnt)
		return ERR_PTR(-ENOMEM);

	clnt->trans_mod = NULL;
	clnt->trans = NULL;
	spin_lock_init(&