[linux-2.6-block.git] / fs / 9p / v9fs.c

/*
 *  linux/fs/9p/v9fs.c
 *
 *  This file contains functions assisting in mapping VFS to 9P2000
 *
 *  Copyright (C) 2004 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 as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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/config.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/parser.h>
#include <linux/idr.h>

#include "debug.h"
#include "v9fs.h"
#include "9p.h"
#include "v9fs_vfs.h"
#include "transport.h"
#include "mux.h"

/* TODO: sysfs or debugfs interface */
int v9fs_debug_level = 0;	/* feature-rific global debug level  */

/*
  * Option Parsing (code inspired by NFS code)
  *
  */

enum {
	/* Options that take integer arguments */
	Opt_port, Opt_msize, Opt_uid, Opt_gid, Opt_afid, Opt_debug,
	Opt_rfdno, Opt_wfdno,
	/* String options */
	Opt_name, Opt_remotename,
	/* Options that take no arguments */
	Opt_legacy, Opt_nodevmap, Opt_unix, Opt_tcp, Opt_fd,
	/* Error token */
	Opt_err
};

static match_table_t tokens = {
	{Opt_port, "port=%u"},
	{Opt_msize, "msize=%u"},
	{Opt_uid, "uid=%u"},
	{Opt_gid, "gid=%u"},
	{Opt_afid, "afid=%u"},
	{Opt_rfdno, "rfdno=%u"},
	{Opt_wfdno, "wfdno=%u"},
	{Opt_debug, "debug=%u"},
	{Opt_name, "name=%s"},
	{Opt_remotename, "aname=%s"},
	{Opt_unix, "proto=unix"},
	{Opt_tcp, "proto=tcp"},
	{Opt_fd, "proto=fd"},
	{Opt_tcp, "tcp"},
	{Opt_unix, "unix"},
	{Opt_fd, "fd"},
	{Opt_legacy, "noextend"},
	{Opt_nodevmap, "nodevmap"},
	{Opt_err, NULL}
};

/*
 *  Parse option string.
 */

/**
 * v9fs_parse_options - parse mount options into session structure
 * @options: options string passed from mount
 * @v9ses: existing v9fs session information
 *
 */

static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
{
	char *p;
	substring_t args[MAX_OPT_ARGS];
	int option;
	int ret;

	/* setup defaults */
	v9ses->port = V9FS_PORT;
	v9ses->maxdata = 9000;
	v9ses->proto = PROTO_TCP;
	v9ses->extended = 1;
	v9ses->afid = ~0;
	v9ses->debug = 0;
	v9ses->rfdno = ~0;
	v9ses->wfdno = ~0;

	if (!options)
		return;

	while ((p = strsep(&options, ",")) != NULL) {
		int token;
		if (!*p)
			continue;
		token = match_token(p, tokens, args);
		if (token < Opt_name) {
			if ((ret = match_int(&args[0], &option)) < 0) {
				dprintk(DEBUG_ERROR,
					"integer field, but no integer?\n");
				continue;
			}

		}
		switch (token) {
		case Opt_port:
			v9ses->port = option;
			break;
		case Opt_msize:
			v9ses->maxdata = option;
			break;
		case Opt_uid:
			v9ses->uid = option;
			break;
		case Opt_gid:
			v9ses->gid = option;
			break;
		case Opt_afid:
			v9ses->afid = option;
			break;
		case Opt_rfdno:
			v9ses->rfdno = option;
			break;
		case Opt_wfdno:
			v9ses->wfdno = option;
			break;
		case Opt_debug:
			v9ses->debug = option;
			break;
		case Opt_tcp:
			v9ses->proto = PROTO_TCP;
			break;
		case Opt_unix:
			v9ses->proto = PROTO_UNIX;
			break;
		case Opt_fd:
			v9ses->proto = PROTO_FD;
			break;
		case Opt_name:
			match_strcpy(v9ses->name, &args[0]);
			break;
		case Opt_remotename:
			match_strcpy(v9ses->remotename, &args[0]);
			break;
		case Opt_legacy:
			v9ses->extended = 0;
			break;
		case Opt_nodevmap:
			v9ses->nodev = 1;
			break;
		default:
			continue;
		}
	}
}

/**
 * v9fs_inode2v9ses - safely extract v9fs session info from super block
 * @inode: inode to extract information from
 *
 * Paranoid function to extract v9ses information from superblock,
 * if anything is missing it will report an error.
 *
 */

struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
{
	return (inode->i_sb->s_fs_info);
}

/**
 * v9fs_get_idpool - allocate numeric id from pool
 * @p - pool to allocate from
 *
 * XXX - This seems to be an awful generic function, should it be in idr.c with
 *            the lock included in struct idr?
 */

int v9fs_get_idpool(struct v9fs_idpool *p)
{
	int i = 0;
	int error;

retry:
	if (idr_pre_get(&p->pool, GFP_KERNEL) == 0)
		return 0;

	if (down_interruptible(&p->lock) == -EINTR) {
		eprintk(KERN_WARNING, "Interrupted while locking\n");
		return -1;
	}

	/* no need to store exactly p, we just need something non-null */
	error = idr_get_new(&p->pool, p, &i);
	up(&p->lock);

	if (error == -EAGAIN)
		goto retry;
	else if (error)
		return -1;

	return i;
}

/**
 * v9fs_put_idpool - release numeric id from pool
 * @p - pool to allocate from
 *
 * XXX - This seems to be an awful generic function, should it be in idr.c with
 *            the lock included in struct idr?
 */

void v9fs_put_idpool(int id, struct v9fs_idpool *p)
{
	if (down_interruptible(&p->lock) == -EINTR) {
		eprintk(KERN_WARNING, "Interrupted while locking\n");
		return;
	}
	idr_remove(&p->pool, id);
	up(&p->lock);
}

/**
 * v9fs_check_idpool - check if the specified id is available
 * @id - id to check
 * @p - pool
 */
int v9fs_check_idpool(int id, struct v9fs_idpool *p)
{
	return idr_find(&p->pool, id) != NULL;
}

/**
 * v9fs_session_init - initialize session
 * @v9ses: session information structure
 * @dev_name: device being mounted
 * @data: options
 *
 */

int
v9fs_session_init(struct v9fs_session_info *v9ses,
		  const char *dev_name, char *data)
{
	struct v9fs_fcall *fcall = NULL;
	struct v9fs_transport *trans_proto;
	int n = 0;
	int newfid = -1;
	int retval = -EINVAL;
	struct v9fs_str *version;

	v9ses->name = __getname();
	if (!v9ses->name)
		return -ENOMEM;

	v9ses->remotename = __getname();
	if (!v9ses->remotename) {
		__putname(v9ses->name);
		return -ENOMEM;
	}

	strcpy(v9ses->name, V9FS_DEFUSER);
	strcpy(v9ses->remotename, V9FS_DEFANAME);

	v9fs_parse_options(data, v9ses);

	/* set global debug level */
	v9fs_debug_level = v9ses->debug;

	/* id pools that are session-dependent: FIDs and TIDs */
	idr_init(&v9ses->fidpool.pool);
	init_MUTEX(&v9ses->fidpool.lock);

	switch (v9ses->proto) {
	case PROTO_TCP:
		trans_proto = &v9fs_trans_tcp;
		break;
	case PROTO_UNIX:
		trans_proto = &v9fs_trans_unix;
		*v9ses->remotename = 0;
		break;
	case PROTO_FD:
		trans_proto = &v9fs_trans_fd;
		*v9ses->remotename = 0;
		break;
	default:
		printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);
		retval = -ENOPROTOOPT;
		goto SessCleanUp;
	};

	v9ses->transport = kmalloc(sizeof(*v9ses->transport), GFP_KERNEL);
	if (!v9ses->transport) {
		retval = -ENOMEM;
		goto SessCleanUp;
	}

	memmove(v9ses->transport, trans_proto, sizeof(*v9ses->transport));

	if ((retval = v9ses->transport->init(v9ses, dev_name, data)) < 0) {
		eprintk(KERN_ERR, "problem initializing transport\n");
		goto SessCleanUp;
	}

	v9ses->inprogress = 0;
	v9ses->shutdown = 0;
	v9ses->session_hung = 0;

	v9ses->mux = v9fs_mux_init(v9ses->transport, v9ses->maxdata + V9FS_IOHDRSZ,
		&v9ses->extended);

	if (IS_ERR(v9ses->mux)) {
		retval = PTR_ERR(v9ses->mux);
		v9ses->mux = NULL;
		dprintk(DEBUG_ERROR, "problem initializing mux\n");
		goto SessCleanUp;
	}

	if (v9ses->afid == ~0) {
		if (v9ses->extended)
			retval =
			    v9fs_t_version(v9ses, v9ses->maxdata, "9P2000.u",
					   &fcall);
		else
			retval = v9fs_t_version(v9ses, v9ses->maxdata, "9P2000",
						&fcall);

		if (retval < 0) {
			dprintk(DEBUG_ERROR, "v9fs_t_version failed\n");
			goto FreeFcall;
		}

		version = &fcall->params.rversion.version;
		if (version->len==8 && !memcmp(version->str, "9P2000.u", 8)) {
			dprintk(DEBUG_9P, "9P2000 UNIX extensions enabled\n");
			v9ses->extended = 1;
		} else if (version->len==6 && !memcmp(version->str, "9P2000", 6)) {
			dprintk(DEBUG_9P, "9P2000 legacy mode enabled\n");
			v9ses->extended = 0;
		} else {
			retval = -EREMOTEIO;
			goto FreeFcall;
		}

		n = fcall->params.rversion.msize;
		kfree(fcall);

		if (n < v9ses->maxdata)
			v9ses->maxdata = n;
	}

	newfid = v9fs_get_idpool(&v9ses->fidpool);
	if (newfid < 0) {
		eprintk(KERN_WARNING, "couldn't allocate FID\n");
		retval = -ENOMEM;
		goto SessCleanUp;
	}
	/* it is a little bit ugly, but we have to prevent newfid */
	/* being the same as afid, so if it is, get a new fid     */
	if (v9ses->afid != ~0 && newfid == v9ses->afid) {
		newfid = v9fs_get_idpool(&v9ses->fidpool);
		if (newfid < 0) {
			eprintk(KERN_WARNING, "couldn't allocate FID\n");
			retval = -ENOMEM;
			goto SessCleanUp;
		}
	}

	if ((retval =
	     v9fs_t_attach(v9ses, v9ses->name, v9ses->remotename, newfid,
			   v9ses->afid, NULL))
	    < 0) {
		dprintk(DEBUG_ERROR, "cannot attach\n");
		goto SessCleanUp;
	}

	if (v9ses->afid != ~0) {
		if (v9fs_t_clunk(v9ses, v9ses->afid))
			dprintk(DEBUG_ERROR, "clunk failed\n");
	}

	return newfid;

      FreeFcall:
	kfree(fcall);

      SessCleanUp:
	v9fs_session_close(v9ses);
	return retval;
}

/**
 * v9fs_session_close - shutdown a session
 * @v9ses: session information structure
 *
 */

void v9fs_session_close(struct v9fs_session_info *v9ses)
{
	if (v9ses->mux) {
		v9fs_mux_destroy(v9ses->mux);
		v9ses->mux = NULL;
	}

	if (v9ses->transport) {
		v9ses->transport->close(v9ses->transport);
		kfree(v9ses->transport);
		v9ses->transport = NULL;
	}

	__putname(v9ses->name);
	__putname(v9ses->remotename);
}

/**
 * v9fs_session_cancel - mark transport as disconnected
 * 	and cancel all pending requests.
 */
void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
	dprintk(DEBUG_ERROR, "cancel session %p\n", v9ses);
	v9ses->transport->status = Disconnected;
	v9fs_mux_cancel(v9ses->mux, -EIO);
}

extern int v9fs_error_init(void);

/**
 * v9fs_init - Initialize module
 *
 */

static int __init init_v9fs(void)
{
	int ret;

	v9fs_error_init();

	printk(KERN_INFO "Installing v9fs 9P2000 file system support\n");

	ret = v9fs_mux_global_init();
	if (!ret)
		ret = register_filesystem(&v9fs_fs_type);

	return ret;
}

/**
 * v9fs_init - shutdown module
 *
 */

static void __exit exit_v9fs(void)
{
	v9fs_mux_global_exit();
	unregister_filesystem(&v9fs_fs_type);
}

module_init(init_v9fs)
module_exit(exit_v9fs)

MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
MODULE_LICENSE("GPL");
Commit	Line	Data
9e82cf6a EVH	1	/*
	2	* linux/fs/9p/v9fs.c
	3	*
	4	* This file contains functions assisting in mapping VFS to 9P2000
	5	*
	6	* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
	7	* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or
	12	* (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to:
	21	* Free Software Foundation
	22	* 51 Franklin Street, Fifth Floor
	23	* Boston, MA 02111-1301 USA
	24	*
	25	*/
	26
	27	#include <linux/config.h>
	28	#include <linux/module.h>
	29	#include <linux/errno.h>
	30	#include <linux/fs.h>
	31	#include <linux/parser.h>
	32	#include <linux/idr.h>
	33
	34	#include "debug.h"
	35	#include "v9fs.h"
	36	#include "9p.h"
	37	#include "v9fs_vfs.h"
	38	#include "transport.h"
	39	#include "mux.h"
9e82cf6a EVH	40
	41	/* TODO: sysfs or debugfs interface */
	42	int v9fs_debug_level = 0; /* feature-rific global debug level */
	43
	44	/*
	45	* Option Parsing (code inspired by NFS code)
	46	*
	47	*/
	48
	49	enum {
	50	/* Options that take integer arguments */
	51	Opt_port, Opt_msize, Opt_uid, Opt_gid, Opt_afid, Opt_debug,
	52	Opt_rfdno, Opt_wfdno,
	53	/* String options */
	54	Opt_name, Opt_remotename,
	55	/* Options that take no arguments */
	56	Opt_legacy, Opt_nodevmap, Opt_unix, Opt_tcp, Opt_fd,
	57	/* Error token */
	58	Opt_err
	59	};
	60
	61	static match_table_t tokens = {
	62	{Opt_port, "port=%u"},
	63	{Opt_msize, "msize=%u"},
	64	{Opt_uid, "uid=%u"},
	65	{Opt_gid, "gid=%u"},
	66	{Opt_afid, "afid=%u"},
	67	{Opt_rfdno, "rfdno=%u"},
	68	{Opt_wfdno, "wfdno=%u"},
	69	{Opt_debug, "debug=%u"},
	70	{Opt_name, "name=%s"},
	71	{Opt_remotename, "aname=%s"},
	72	{Opt_unix, "proto=unix"},
	73	{Opt_tcp, "proto=tcp"},
	74	{Opt_fd, "proto=fd"},
	75	{Opt_tcp, "tcp"},
	76	{Opt_unix, "unix"},
	77	{Opt_fd, "fd"},
	78	{Opt_legacy, "noextend"},
	79	{Opt_nodevmap, "nodevmap"},
	80	{Opt_err, NULL}
	81	};
	82
	83	/*
	84	* Parse option string.
	85	*/
	86
	87	/**
	88	* v9fs_parse_options - parse mount options into session structure
	89	* @options: options string passed from mount
	90	* @v9ses: existing v9fs session information
	91	*
	92	*/
	93
	94	static void v9fs_parse_options(char options, struct v9fs_session_info v9ses)
	95	{
	96	char *p;
	97	substring_t args[MAX_OPT_ARGS];
	98	int option;
	99	int ret;
	100
	101	/* setup defaults */
	102	v9ses->port = V9FS_PORT;
	103	v9ses->maxdata = 9000;
104	v9ses->proto = PROTO_TCP;
105	v9ses->extended = 1;
106	v9ses->afid = ~0;
107	v9ses->debug = 0;
108	v9ses->rfdno = ~0;
109	v9ses->wfdno = ~0;
110
111	if (!options)
112	return;
113
114	while ((p = strsep(&options, ",")) != NULL) {
115	int token;
116	if (!*p)
117	continue;
118	token = match_token(p, tokens, args);
119	if (token < Opt_name) {
120	if ((ret = match_int(&args[0], &option)) < 0) {
121	dprintk(DEBUG_ERROR,
122	"integer field, but no integer?\n");
123	continue;
124	}
125
126	}
127	switch (token) {
128	case Opt_port:
129	v9ses->port = option;
130	break;
131	case Opt_msize:
132	v9ses->maxdata = option;
133	break;
134	case Opt_uid:
135	v9ses->uid = option;
136	break;
137	case Opt_gid:
138	v9ses->gid = option;
139	break;
140	case Opt_afid:
141	v9ses->afid = option;
142	break;
143	case Opt_rfdno:
144	v9ses->rfdno = option;
145	break;
146	case Opt_wfdno:
147	v9ses->wfdno = option;
148	break;
149	case Opt_debug:
150	v9ses->debug = option;
151	break;
152	case Opt_tcp:
153	v9ses->proto = PROTO_TCP;
154	break;
155	case Opt_unix:
156	v9ses->proto = PROTO_UNIX;
157	break;
158	case Opt_fd:
159	v9ses->proto = PROTO_FD;
160	break;
161	case Opt_name:
162	match_strcpy(v9ses->name, &args[0]);
163	break;
164	case Opt_remotename:
165	match_strcpy(v9ses->remotename, &args[0]);
166	break;
167	case Opt_legacy:
168	v9ses->extended = 0;
169	break;
170	case Opt_nodevmap:
171	v9ses->nodev = 1;
172	break;
173	default:
174	continue;
175	}
176	}
177	}
178
179	/**
180	* v9fs_inode2v9ses - safely extract v9fs session info from super block
181	* @inode: inode to extract information from
182	*
183	* Paranoid function to extract v9ses information from superblock,
184	* if anything is missing it will report an error.
185	*
186	*/
187
188	struct v9fs_session_info v9fs_inode2v9ses(struct inode inode)
189	{
190	return (inode->i_sb->s_fs_info);
191	}
192
193	/**
194	* v9fs_get_idpool - allocate numeric id from pool
195	* @p - pool to allocate from
196	*
197	* XXX - This seems to be an awful generic function, should it be in idr.c with
198	* the lock included in struct idr?
199	*/
200
201	int v9fs_get_idpool(struct v9fs_idpool *p)
202	{
203	int i = 0;
204	int error;
205
206	retry:
207	if (idr_pre_get(&p->pool, GFP_KERNEL) == 0)
208	return 0;
209
210	if (down_interruptible(&p->lock) == -EINTR) {
211	eprintk(KERN_WARNING, "Interrupted while locking\n");
212	return -1;
213	}
214
3cf6429a LI	215	/* no need to store exactly p, we just need something non-null */
3cf6429a LI	216	error = idr_get_new(&p->pool, p, &i);
9e82cf6a EVH	217	up(&p->lock);
	218
	219	if (error == -EAGAIN)
	220	goto retry;
	221	else if (error)
	222	return -1;
	223
	224	return i;
	225	}
	226
	227	/**
	228	* v9fs_put_idpool - release numeric id from pool
	229	* @p - pool to allocate from
	230	*
	231	* XXX - This seems to be an awful generic function, should it be in idr.c with
	232	* the lock included in struct idr?
	233	*/
	234
	235	void v9fs_put_idpool(int id, struct v9fs_idpool *p)
	236	{
	237	if (down_interruptible(&p->lock) == -EINTR) {
	238	eprintk(KERN_WARNING, "Interrupted while locking\n");
	239	return;
	240	}
	241	idr_remove(&p->pool, id);
	242	up(&p->lock);
	243	}
	244
3cf6429a LI	245	/**
	246	* v9fs_check_idpool - check if the specified id is available
	247	* @id - id to check
	248	* @p - pool
	249	*/
	250	int v9fs_check_idpool(int id, struct v9fs_idpool *p)
	251	{
	252	return idr_find(&p->pool, id) != NULL;
	253	}
	254
9e82cf6a EVH	255	/**
	256	* v9fs_session_init - initialize session
	257	* @v9ses: session information structure
	258	* @dev_name: device being mounted
	259	* @data: options
	260	*
	261	*/
	262
	263	int
	264	v9fs_session_init(struct v9fs_session_info *v9ses,
	265	const char dev_name, char data)
	266	{
	267	struct v9fs_fcall *fcall = NULL;
	268	struct v9fs_transport *trans_proto;
	269	int n = 0;
	270	int newfid = -1;
	271	int retval = -EINVAL;
1dac06b2	272	struct v9fs_str *version;
9e82cf6a EVH	273
	274	v9ses->name = __getname();
	275	if (!v9ses->name)
	276	return -ENOMEM;
	277
	278	v9ses->remotename = __getname();
	279	if (!v9ses->remotename) {
ce44eeb6	280	__putname(v9ses->name);
9e82cf6a EVH	281	return -ENOMEM;
	282	}
	283
	284	strcpy(v9ses->name, V9FS_DEFUSER);
	285	strcpy(v9ses->remotename, V9FS_DEFANAME);
	286
	287	v9fs_parse_options(data, v9ses);
	288
	289	/* set global debug level */
	290	v9fs_debug_level = v9ses->debug;
	291
	292	/* id pools that are session-dependent: FIDs and TIDs */
	293	idr_init(&v9ses->fidpool.pool);
	294	init_MUTEX(&v9ses->fidpool.lock);
9e82cf6a EVH	295
	296	switch (v9ses->proto) {
	297	case PROTO_TCP:
	298	trans_proto = &v9fs_trans_tcp;
	299	break;
	300	case PROTO_UNIX:
	301	trans_proto = &v9fs_trans_unix;
	302	*v9ses->remotename = 0;
	303	break;
	304	case PROTO_FD:
	305	trans_proto = &v9fs_trans_fd;
	306	*v9ses->remotename = 0;
9e82cf6a EVH	307	break;
	308	default:
	309	printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);
	310	retval = -ENOPROTOOPT;
	311	goto SessCleanUp;
	312	};
	313
a8e63bff LI	314	v9ses->transport = kmalloc(sizeof(*v9ses->transport), GFP_KERNEL);
	315	if (!v9ses->transport) {
	316	retval = -ENOMEM;
	317	goto SessCleanUp;
	318	}
	319
	320	memmove(v9ses->transport, trans_proto, sizeof(*v9ses->transport));
9e82cf6a EVH	321
	322	if ((retval = v9ses->transport->init(v9ses, dev_name, data)) < 0) {
	323	eprintk(KERN_ERR, "problem initializing transport\n");
	324	goto SessCleanUp;
	325	}
	326
	327	v9ses->inprogress = 0;
	328	v9ses->shutdown = 0;
	329	v9ses->session_hung = 0;
	330
3cf6429a LI	331	v9ses->mux = v9fs_mux_init(v9ses->transport, v9ses->maxdata + V9FS_IOHDRSZ,
	332	&v9ses->extended);
	333
	334	if (IS_ERR(v9ses->mux)) {
	335	retval = PTR_ERR(v9ses->mux);
	336	v9ses->mux = NULL;
9e82cf6a EVH	337	dprintk(DEBUG_ERROR, "problem initializing mux\n");
	338	goto SessCleanUp;
	339	}
	340
	341	if (v9ses->afid == ~0) {
	342	if (v9ses->extended)
	343	retval =
	344	v9fs_t_version(v9ses, v9ses->maxdata, "9P2000.u",
	345	&fcall);
	346	else
	347	retval = v9fs_t_version(v9ses, v9ses->maxdata, "9P2000",
	348	&fcall);
	349
	350	if (retval < 0) {
	351	dprintk(DEBUG_ERROR, "v9fs_t_version failed\n");
	352	goto FreeFcall;
	353	}
	354
1dac06b2 LI	355	version = &fcall->params.rversion.version;
1dac06b2 LI	356	if (version->len==8 && !memcmp(version->str, "9P2000.u", 8)) {
9e82cf6a EVH	357	dprintk(DEBUG_9P, "9P2000 UNIX extensions enabled\n");
9e82cf6a EVH	358	v9ses->extended = 1;
1dac06b2	359	} else if (version->len==6 && !memcmp(version->str, "9P2000", 6)) {
9e82cf6a EVH	360	dprintk(DEBUG_9P, "9P2000 legacy mode enabled\n");
9e82cf6a EVH	361	v9ses->extended = 0;
1dac06b2 LI	362	} else {
	363	retval = -EREMOTEIO;
	364	goto FreeFcall;
9e82cf6a EVH	365	}
	366
	367	n = fcall->params.rversion.msize;
	368	kfree(fcall);
	369
	370	if (n < v9ses->maxdata)
	371	v9ses->maxdata = n;
	372	}
	373
	374	newfid = v9fs_get_idpool(&v9ses->fidpool);
	375	if (newfid < 0) {
	376	eprintk(KERN_WARNING, "couldn't allocate FID\n");
	377	retval = -ENOMEM;
	378	goto SessCleanUp;
	379	}
	380	/* it is a little bit ugly, but we have to prevent newfid */
	381	/* being the same as afid, so if it is, get a new fid */
	382	if (v9ses->afid != ~0 && newfid == v9ses->afid) {
	383	newfid = v9fs_get_idpool(&v9ses->fidpool);
	384	if (newfid < 0) {
	385	eprintk(KERN_WARNING, "couldn't allocate FID\n");
	386	retval = -ENOMEM;
	387	goto SessCleanUp;
	388	}
	389	}
	390
	391	if ((retval =
	392	v9fs_t_attach(v9ses, v9ses->name, v9ses->remotename, newfid,
	393	v9ses->afid, NULL))
	394	< 0) {
	395	dprintk(DEBUG_ERROR, "cannot attach\n");
	396	goto SessCleanUp;
	397	}
	398
	399	if (v9ses->afid != ~0) {
3cf6429a	400	if (v9fs_t_clunk(v9ses, v9ses->afid))
9e82cf6a EVH	401	dprintk(DEBUG_ERROR, "clunk failed\n");
	402	}
	403
	404	return newfid;
	405
	406	FreeFcall:
	407	kfree(fcall);
	408
	409	SessCleanUp:
	410	v9fs_session_close(v9ses);
	411	return retval;
	412	}
	413
	414	/**
	415	* v9fs_session_close - shutdown a session
	416	* @v9ses: session information structure
	417	*
	418	*/
	419
	420	void v9fs_session_close(struct v9fs_session_info *v9ses)
	421	{
3cf6429a LI	422	if (v9ses->mux) {
	423	v9fs_mux_destroy(v9ses->mux);
	424	v9ses->mux = NULL;
9e82cf6a EVH	425	}
9e82cf6a EVH	426
3cf6429a	427	if (v9ses->transport) {
9e82cf6a	428	v9ses->transport->close(v9ses->transport);
3cf6429a LI	429	kfree(v9ses->transport);
	430	v9ses->transport = NULL;
	431	}
9e82cf6a	432
ce44eeb6 DA	433	__putname(v9ses->name);
ce44eeb6 DA	434	__putname(v9ses->remotename);
9e82cf6a EVH	435	}
9e82cf6a EVH	436
322b329a EVH	437	/**
	438	* v9fs_session_cancel - mark transport as disconnected
	439	* and cancel all pending requests.
	440	*/
	441	void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
3cf6429a	442	dprintk(DEBUG_ERROR, "cancel session %p\n", v9ses);
322b329a	443	v9ses->transport->status = Disconnected;
3cf6429a	444	v9fs_mux_cancel(v9ses->mux, -EIO);
322b329a EVH	445	}
322b329a EVH	446
9e82cf6a EVH	447	extern int v9fs_error_init(void);
	448
	449	/**
	450	* v9fs_init - Initialize module
	451	*
	452	*/
	453
	454	static int __init init_v9fs(void)
	455	{
1dac06b2 LI	456	int ret;
1dac06b2 LI	457
9e82cf6a EVH	458	v9fs_error_init();
	459
	460	printk(KERN_INFO "Installing v9fs 9P2000 file system support\n");
	461
1dac06b2 LI	462	ret = v9fs_mux_global_init();
	463	if (!ret)
	464	ret = register_filesystem(&v9fs_fs_type);
	465
	466	return ret;
9e82cf6a EVH	467	}
	468
	469	/**
	470	* v9fs_init - shutdown module
	471	*
	472	*/
	473
	474	static void __exit exit_v9fs(void)
	475	{
3cf6429a	476	v9fs_mux_global_exit();
9e82cf6a EVH	477	unregister_filesystem(&v9fs_fs_type);
	478	}
	479
	480	module_init(init_v9fs)
	481	module_exit(exit_v9fs)
	482
	483	MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
	484	MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
	485	MODULE_LICENSE("GPL");