[net-next-2.6.git] / fs / 9p / v9fs.c

/*
 *  linux/fs/9p/v9fs.c
 *
 *  This file contains functions assisting in mapping VFS to 9P2000
 *
 *  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
 *
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/parser.h>
#include <linux/idr.h>
#include <net/9p/9p.h>
#include <net/9p/transport.h>
#include <net/9p/client.h>
#include "v9fs.h"
#include "v9fs_vfs.h"

/*
  * Option Parsing (code inspired by NFS code)
  *  NOTE: each transport will parse its own options
  */

enum {
	/* Options that take integer arguments */
	Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
	/* String options */
	Opt_uname, Opt_remotename, Opt_trans,
	/* Options that take no arguments */
	Opt_nodevmap,
	/* Cache options */
	Opt_cache_loose,
	/* Access options */
	Opt_access,
	/* Error token */
	Opt_err
};

static match_table_t tokens = {
	{Opt_debug, "debug=%x"},
	{Opt_dfltuid, "dfltuid=%u"},
	{Opt_dfltgid, "dfltgid=%u"},
	{Opt_afid, "afid=%u"},
	{Opt_uname, "uname=%s"},
	{Opt_remotename, "aname=%s"},
	{Opt_nodevmap, "nodevmap"},
	{Opt_cache_loose, "cache=loose"},
	{Opt_cache_loose, "loose"},
	{Opt_access, "access=%s"},
	{Opt_err, NULL}
};

/**
 * 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(struct v9fs_session_info *v9ses)
{
	char *options;
	substring_t args[MAX_OPT_ARGS];
	char *p;
	int option = 0;
	char *s, *e;
	int ret;

	/* setup defaults */
	v9ses->afid = ~0;
	v9ses->debug = 0;
	v9ses->cache = 0;

	if (!v9ses->options)
		return;

	options = kstrdup(v9ses->options, GFP_KERNEL);
	while ((p = strsep(&options, ",")) != NULL) {
		int token;
		if (!*p)
			continue;
		token = match_token(p, tokens, args);
		if (token < Opt_uname) {
			ret = match_int(&args[0], &option);
			if (ret < 0) {
				P9_DPRINTK(P9_DEBUG_ERROR,
					"integer field, but no integer?\n");
				continue;
			}
		}
		switch (token) {
		case Opt_debug:
			v9ses->debug = option;
#ifdef CONFIG_NET_9P_DEBUG
			p9_debug_level = option;
#endif
			break;

		case Opt_dfltuid:
			v9ses->dfltuid = option;
			break;
		case Opt_dfltgid:
			v9ses->dfltgid = option;
			break;
		case Opt_afid:
			v9ses->afid = option;
			break;
		case Opt_uname:
			match_strcpy(v9ses->uname, &args[0]);
			break;
		case Opt_remotename:
			match_strcpy(v9ses->aname, &args[0]);
			break;
		case Opt_nodevmap:
			v9ses->nodev = 1;
			break;
		case Opt_cache_loose:
			v9ses->cache = CACHE_LOOSE;
			break;

		case Opt_access:
			s = match_strdup(&args[0]);
			v9ses->flags &= ~V9FS_ACCESS_MASK;
			if (strcmp(s, "user") == 0)
				v9ses->flags |= V9FS_ACCESS_USER;
			else if (strcmp(s, "any") == 0)
				v9ses->flags |= V9FS_ACCESS_ANY;
			else {
				v9ses->flags |= V9FS_ACCESS_SINGLE;
				v9ses->uid = simple_strtol(s, &e, 10);
				if (*e != '\0')
					v9ses->uid = ~0;
			}
			kfree(s);
			break;

		default:
			continue;
		}
	}
	kfree(options);
}

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

struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
		  const char *dev_name, char *data)
{
	int retval = -EINVAL;
	struct p9_fid *fid;

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

	v9ses->aname = __getname();
	if (!v9ses->aname) {
		__putname(v9ses->uname);
		return ERR_PTR(-ENOMEM);
	}

	v9ses->flags = V9FS_EXTENDED | V9FS_ACCESS_USER;
	strcpy(v9ses->uname, V9FS_DEFUSER);
	strcpy(v9ses->aname, V9FS_DEFANAME);
	v9ses->uid = ~0;
	v9ses->dfltuid = V9FS_DEFUID;
	v9ses->dfltgid = V9FS_DEFGID;
	v9ses->options = kstrdup(data, GFP_KERNEL);
	v9fs_parse_options(v9ses);

	v9ses->clnt = p9_client_create(dev_name, v9ses->options);

	if (IS_ERR(v9ses->clnt)) {
		retval = PTR_ERR(v9ses->clnt);
		v9ses->clnt = NULL;
		P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
		goto error;
	}

	if (!v9ses->clnt->dotu)
		v9ses->flags &= ~V9FS_EXTENDED;

	v9ses->maxdata = v9ses->clnt->msize;

	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
	if (!v9fs_extended(v9ses) &&
		((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {

		v9ses->flags &= ~V9FS_ACCESS_MASK;
		v9ses->flags |= V9FS_ACCESS_ANY;
		v9ses->uid = ~0;
	}

	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
							v9ses->aname);
	if (IS_ERR(fid)) {
		retval = PTR_ERR(fid);
		fid = NULL;
		P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
		goto error;
	}

	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
		fid->uid = v9ses->uid;
	else
		fid->uid = ~0;

	return fid;

error:
	v9fs_session_close(v9ses);
	return ERR_PTR(retval);
}

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

void v9fs_session_close(struct v9fs_session_info *v9ses)
{
	if (v9ses->clnt) {
		p9_client_destroy(v9ses->clnt);
		v9ses->clnt = NULL;
	}

	__putname(v9ses->uname);
	__putname(v9ses->aname);
	kfree(v9ses->options);
}

/**
 * v9fs_session_cancel - mark transport as disconnected
 * 	and cancel all pending requests.
 */
void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
	P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
	p9_client_disconnect(v9ses->clnt);
}

extern int v9fs_error_init(void);

/**
 * v9fs_init - Initialize module
 *
 */

static int __init init_v9fs(void)
{
	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
	/* TODO: Setup list of registered trasnport modules */
	return register_filesystem(&v9fs_fs_type);
}

/**
 * v9fs_init - shutdown module
 *
 */

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

module_init(init_v9fs)
module_exit(exit_v9fs)

MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
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	*
8a0dc95f	6	* Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
9e82cf6a EVH	7	* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
	8	*
	9	* This program is free software; you can redistribute it and/or modify
42e8c509 EVH	10	* it under the terms of the GNU General Public License version 2
42e8c509 EVH	11	* as published by the Free Software Foundation.
9e82cf6a EVH	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to:
	20	* Free Software Foundation
	21	* 51 Franklin Street, Fifth Floor
	22	* Boston, MA 02111-1301 USA
	23	*
	24	*/
	25
9e82cf6a EVH	26	#include <linux/module.h>
	27	#include <linux/errno.h>
	28	#include <linux/fs.h>
914e2637	29	#include <linux/sched.h>
9e82cf6a EVH	30	#include <linux/parser.h>
9e82cf6a EVH	31	#include <linux/idr.h>
bd238fb4 LI	32	#include <net/9p/9p.h>
bd238fb4 LI	33	#include <net/9p/transport.h>
bd238fb4	34	#include <net/9p/client.h>
9e82cf6a	35	#include "v9fs.h"
9e82cf6a	36	#include "v9fs_vfs.h"
9e82cf6a EVH	37
	38	/*
	39	* Option Parsing (code inspired by NFS code)
a80d923e	40	* NOTE: each transport will parse its own options
9e82cf6a EVH	41	*/
	42
	43	enum {
	44	/* Options that take integer arguments */
8a0dc95f	45	Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
9e82cf6a	46	/* String options */
a80d923e	47	Opt_uname, Opt_remotename, Opt_trans,
9e82cf6a	48	/* Options that take no arguments */
8a0dc95f	49	Opt_nodevmap,
e03abc0c EVH	50	/* Cache options */
e03abc0c EVH	51	Opt_cache_loose,
ba17674f LI	52	/* Access options */
ba17674f LI	53	Opt_access,
9e82cf6a EVH	54	/* Error token */
	55	Opt_err
	56	};
	57
	58	static match_table_t tokens = {
9e2f6688	59	{Opt_debug, "debug=%x"},
bd32b82d LI	60	{Opt_dfltuid, "dfltuid=%u"},
bd32b82d LI	61	{Opt_dfltgid, "dfltgid=%u"},
9e82cf6a	62	{Opt_afid, "afid=%u"},
67543e50	63	{Opt_uname, "uname=%s"},
9e82cf6a	64	{Opt_remotename, "aname=%s"},
9e82cf6a	65	{Opt_nodevmap, "nodevmap"},
e03abc0c EVH	66	{Opt_cache_loose, "cache=loose"},
e03abc0c EVH	67	{Opt_cache_loose, "loose"},
ba17674f	68	{Opt_access, "access=%s"},
9e82cf6a EVH	69	{Opt_err, NULL}
	70	};
	71
9e82cf6a EVH	72	/**
	73	* v9fs_parse_options - parse mount options into session structure
	74	* @options: options string passed from mount
	75	* @v9ses: existing v9fs session information
	76	*
	77	*/
	78
a80d923e	79	static void v9fs_parse_options(struct v9fs_session_info *v9ses)
9e82cf6a	80	{
8999e04f	81	char *options;
9e82cf6a	82	substring_t args[MAX_OPT_ARGS];
a80d923e	83	char *p;
8a0dc95f	84	int option = 0;
ba17674f	85	char s, e;
8a0dc95f	86	int ret;
9e82cf6a EVH	87
9e82cf6a EVH	88	/* setup defaults */
9e82cf6a EVH	89	v9ses->afid = ~0;
9e82cf6a EVH	90	v9ses->debug = 0;
e03abc0c	91	v9ses->cache = 0;
9e82cf6a	92
8999e04f	93	if (!v9ses->options)
9e82cf6a EVH	94	return;
9e82cf6a EVH	95
8999e04f	96	options = kstrdup(v9ses->options, GFP_KERNEL);
9e82cf6a EVH	97	while ((p = strsep(&options, ",")) != NULL) {
	98	int token;
	99	if (!*p)
	100	continue;
	101	token = match_token(p, tokens, args);
67543e50	102	if (token < Opt_uname) {
8a0dc95f EVH	103	ret = match_int(&args[0], &option);
8a0dc95f EVH	104	if (ret < 0) {
bd238fb4	105	P9_DPRINTK(P9_DEBUG_ERROR,
9e82cf6a EVH	106	"integer field, but no integer?\n");
	107	continue;
	108	}
9e82cf6a EVH	109	}
9e82cf6a EVH	110	switch (token) {
9e2f6688 EVH	111	case Opt_debug:
9e2f6688 EVH	112	v9ses->debug = option;
10fa16e7	113	#ifdef CONFIG_NET_9P_DEBUG
9e2f6688	114	p9_debug_level = option;
10fa16e7	115	#endif
9e2f6688	116	break;
8a0dc95f	117
bd32b82d LI	118	case Opt_dfltuid:
bd32b82d LI	119	v9ses->dfltuid = option;
9e82cf6a	120	break;
bd32b82d LI	121	case Opt_dfltgid:
bd32b82d LI	122	v9ses->dfltgid = option;
9e82cf6a EVH	123	break;
	124	case Opt_afid:
	125	v9ses->afid = option;
	126	break;
67543e50	127	case Opt_uname:
ba17674f	128	match_strcpy(v9ses->uname, &args[0]);
9e82cf6a EVH	129	break;
9e82cf6a EVH	130	case Opt_remotename:
ba17674f	131	match_strcpy(v9ses->aname, &args[0]);
9e82cf6a	132	break;
9e82cf6a EVH	133	case Opt_nodevmap:
	134	v9ses->nodev = 1;
	135	break;
e03abc0c EVH	136	case Opt_cache_loose:
	137	v9ses->cache = CACHE_LOOSE;
	138	break;
ba17674f LI	139
	140	case Opt_access:
	141	s = match_strdup(&args[0]);
	142	v9ses->flags &= ~V9FS_ACCESS_MASK;
	143	if (strcmp(s, "user") == 0)
	144	v9ses->flags \|= V9FS_ACCESS_USER;
	145	else if (strcmp(s, "any") == 0)
	146	v9ses->flags \|= V9FS_ACCESS_ANY;
	147	else {
	148	v9ses->flags \|= V9FS_ACCESS_SINGLE;
	149	v9ses->uid = simple_strtol(s, &e, 10);
	150	if (*e != '\0')
	151	v9ses->uid = ~0;
	152	}
0a976297	153	kfree(s);
ba17674f LI	154	break;
ba17674f LI	155
9e82cf6a EVH	156	default:
	157	continue;
	158	}
	159	}
8999e04f	160	kfree(options);
9e82cf6a EVH	161	}
9e82cf6a EVH	162
9e82cf6a EVH	163	/**
	164	* v9fs_session_init - initialize session
	165	* @v9ses: session information structure
	166	* @dev_name: device being mounted
	167	* @data: options
	168	*
	169	*/
	170
bd238fb4	171	struct p9_fid v9fs_session_init(struct v9fs_session_info v9ses,
9e82cf6a EVH	172	const char dev_name, char data)
9e82cf6a EVH	173	{
9e82cf6a	174	int retval = -EINVAL;
bd238fb4	175	struct p9_fid *fid;
9e82cf6a	176
ba17674f LI	177	v9ses->uname = __getname();
ba17674f LI	178	if (!v9ses->uname)
bd238fb4	179	return ERR_PTR(-ENOMEM);
9e82cf6a	180
ba17674f LI	181	v9ses->aname = __getname();
	182	if (!v9ses->aname) {
	183	__putname(v9ses->uname);
bd238fb4	184	return ERR_PTR(-ENOMEM);
9e82cf6a EVH	185	}
9e82cf6a EVH	186
ba17674f LI	187	v9ses->flags = V9FS_EXTENDED \| V9FS_ACCESS_USER;
	188	strcpy(v9ses->uname, V9FS_DEFUSER);
	189	strcpy(v9ses->aname, V9FS_DEFANAME);
	190	v9ses->uid = ~0;
bd32b82d LI	191	v9ses->dfltuid = V9FS_DEFUID;
bd32b82d LI	192	v9ses->dfltgid = V9FS_DEFGID;
a80d923e EVH	193	v9ses->options = kstrdup(data, GFP_KERNEL);
	194	v9fs_parse_options(v9ses);
	195
8a0dc95f	196	v9ses->clnt = p9_client_create(dev_name, v9ses->options);
9e82cf6a	197
bd238fb4 LI	198	if (IS_ERR(v9ses->clnt)) {
	199	retval = PTR_ERR(v9ses->clnt);
	200	v9ses->clnt = NULL;
	201	P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
	202	goto error;
9e82cf6a EVH	203	}
9e82cf6a EVH	204
ba17674f LI	205	if (!v9ses->clnt->dotu)
	206	v9ses->flags &= ~V9FS_EXTENDED;
	207
8a0dc95f EVH	208	v9ses->maxdata = v9ses->clnt->msize;
8a0dc95f EVH	209
ba17674f LI	210	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
	211	if (!v9fs_extended(v9ses) &&
	212	((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
	213
	214	v9ses->flags &= ~V9FS_ACCESS_MASK;
	215	v9ses->flags \|= V9FS_ACCESS_ANY;
	216	v9ses->uid = ~0;
	217	}
	218
	219	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
	220	v9ses->aname);
bd238fb4 LI	221	if (IS_ERR(fid)) {
	222	retval = PTR_ERR(fid);
	223	fid = NULL;
	224	P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
	225	goto error;
9e82cf6a EVH	226	}
9e82cf6a EVH	227
ba17674f LI	228	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
	229	fid->uid = v9ses->uid;
	230	else
	231	fid->uid = ~0;
	232
bd238fb4	233	return fid;
9e82cf6a	234
bd238fb4	235	error:
9e82cf6a	236	v9fs_session_close(v9ses);
bd238fb4	237	return ERR_PTR(retval);
9e82cf6a EVH	238	}
	239
	240	/**
	241	* v9fs_session_close - shutdown a session
	242	* @v9ses: session information structure
	243	*
	244	*/
	245
	246	void v9fs_session_close(struct v9fs_session_info *v9ses)
	247	{
bd238fb4 LI	248	if (v9ses->clnt) {
	249	p9_client_destroy(v9ses->clnt);
	250	v9ses->clnt = NULL;
3cf6429a	251	}
9e82cf6a	252
ba17674f LI	253	__putname(v9ses->uname);
ba17674f LI	254	__putname(v9ses->aname);
a80d923e	255	kfree(v9ses->options);
9e82cf6a EVH	256	}
9e82cf6a EVH	257
322b329a EVH	258	/**
	259	* v9fs_session_cancel - mark transport as disconnected
	260	* and cancel all pending requests.
	261	*/
	262	void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
bd238fb4 LI	263	P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
bd238fb4 LI	264	p9_client_disconnect(v9ses->clnt);
322b329a EVH	265	}
322b329a EVH	266
9e82cf6a EVH	267	extern int v9fs_error_init(void);
	268
	269	/**
	270	* v9fs_init - Initialize module
	271	*
	272	*/
	273
	274	static int __init init_v9fs(void)
	275	{
f94b3470	276	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
a80d923e	277	/* TODO: Setup list of registered trasnport modules */
bd238fb4	278	return register_filesystem(&v9fs_fs_type);
9e82cf6a EVH	279	}
	280
	281	/**
	282	* v9fs_init - shutdown module
	283	*
	284	*/
	285
	286	static void __exit exit_v9fs(void)
	287	{
	288	unregister_filesystem(&v9fs_fs_type);
	289	}
	290
	291	module_init(init_v9fs)
	292	module_exit(exit_v9fs)
	293
bd238fb4	294	MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
9e82cf6a EVH	295	MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
	296	MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
	297	MODULE_LICENSE("GPL");