[deliverable/linux.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/client.h>
#include <net/9p/transport.h>
#include "v9fs.h"
#include "v9fs_vfs.h"
#include "cache.h"

static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
static LIST_HEAD(v9fs_sessionlist);

/*
 * 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, Opt_cache, Opt_cachetag,
	/* Options that take no arguments */
	Opt_nodevmap,
	/* Cache options */
	Opt_cache_loose, Opt_fscache,
	/* Access options */
	Opt_access,
	/* Error token */
	Opt_err
};

static const 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, "cache=%s"},
	{Opt_cache_loose, "loose"},
	{Opt_fscache, "fscache"},
	{Opt_cachetag, "cachetag=%s"},
	{Opt_access, "access=%s"},
	{Opt_err, NULL}
};

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

static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
{
	char *options, *tmp_options;
	substring_t args[MAX_OPT_ARGS];
	char *p;
	int option = 0;
	char *s, *e;
	int ret = 0;

	/* setup defaults */
	v9ses->afid = ~0;
	v9ses->debug = 0;
	v9ses->cache = 0;
#ifdef CONFIG_9P_FSCACHE
	v9ses->cachetag = NULL;
#endif

	if (!opts)
		return 0;

	tmp_options = kstrdup(opts, GFP_KERNEL);
	if (!tmp_options) {
		ret = -ENOMEM;
		goto fail_option_alloc;
	}
	options = tmp_options;

	while ((p = strsep(&options, ",")) != NULL) {
		int token;
		if (!*p)
			continue;
		token = match_token(p, tokens, args);
		if (token < Opt_uname) {
			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_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_strlcpy(v9ses->uname, &args[0], PATH_MAX);
			break;
		case Opt_remotename:
			match_strlcpy(v9ses->aname, &args[0], PATH_MAX);
			break;
		case Opt_nodevmap:
			v9ses->nodev = 1;
			break;
		case Opt_cache_loose:
			v9ses->cache = CACHE_LOOSE;
			break;
		case Opt_fscache:
			v9ses->cache = CACHE_FSCACHE;
			break;
		case Opt_cachetag:
#ifdef CONFIG_9P_FSCACHE
			v9ses->cachetag = match_strdup(&args[0]);
#endif
			break;
		case Opt_cache:
			s = match_strdup(&args[0]);
			if (!s) {
				ret = -ENOMEM;
				P9_DPRINTK(P9_DEBUG_ERROR,
				  "problem allocating copy of cache arg\n");
				goto free_and_return;
			}

			if (strcmp(s, "loose") == 0)
				v9ses->cache = CACHE_LOOSE;
			else if (strcmp(s, "fscache") == 0)
				v9ses->cache = CACHE_FSCACHE;
			else
				v9ses->cache = CACHE_NONE;
			kfree(s);
			break;

		case Opt_access:
			s = match_strdup(&args[0]);
			if (!s) {
				ret = -ENOMEM;
				P9_DPRINTK(P9_DEBUG_ERROR,
				  "problem allocating copy of access arg\n");
				goto free_and_return;
			}

			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_strtoul(s, &e, 10);
				if (*e != '\0')
					v9ses->uid = ~0;
			}
			kfree(s);
			break;

		default:
			continue;
		}
	}

free_and_return:
	kfree(tmp_options);
fail_option_alloc:
	return ret;
}

/**
 * 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;
	int rc;

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

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

	spin_lock(&v9fs_sessionlist_lock);
	list_add(&v9ses->slist, &v9fs_sessionlist);
	spin_unlock(&v9fs_sessionlist_lock);

	v9ses->flags = V9FS_ACCESS_USER;
	strcpy(v9ses->uname, V9FS_DEFUSER);
	strcpy(v9ses->aname, V9FS_DEFANAME);
	v9ses->uid = ~0;
	v9ses->dfltuid = V9FS_DEFUID;
	v9ses->dfltgid = V9FS_DEFGID;

	rc = v9fs_parse_options(v9ses, data);
	if (rc < 0) {
		retval = rc;
		goto error;
	}

	v9ses->clnt = p9_client_create(dev_name, data);
	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 (p9_is_proto_dotl(v9ses->clnt))
		v9ses->flags |= V9FS_PROTO_2000L;
	else if (p9_is_proto_dotu(v9ses->clnt))
		v9ses->flags |= V9FS_PROTO_2000U;

	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;

	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
	if (!v9fs_proto_dotu(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;

#ifdef CONFIG_9P_FSCACHE
	/* register the session for caching */
	v9fs_cache_session_get_cookie(v9ses);
#endif

	return fid;

error:
	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;
	}

#ifdef CONFIG_9P_FSCACHE
	if (v9ses->fscache) {
		v9fs_cache_session_put_cookie(v9ses);
		kfree(v9ses->cachetag);
	}
#endif
	__putname(v9ses->uname);
	__putname(v9ses->aname);

	spin_lock(&v9fs_sessionlist_lock);
	list_del(&v9ses->slist);
	spin_unlock(&v9fs_sessionlist_lock);
}

/**
 * v9fs_session_cancel - terminate a session
 * @v9ses: session to terminate
 *
 * 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);

static struct kobject *v9fs_kobj;

#ifdef CONFIG_9P_FSCACHE
/**
 * caches_show - list caches associated with a session
 *
 * Returns the size of buffer written.
 */

static ssize_t caches_show(struct kobject *kobj,
			   struct kobj_attribute *attr,
			   char *buf)
{
	ssize_t n = 0, count = 0, limit = PAGE_SIZE;
	struct v9fs_session_info *v9ses;

	spin_lock(&v9fs_sessionlist_lock);
	list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
		if (v9ses->cachetag) {
			n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
			if (n < 0) {
				count = n;
				break;
			}

			count += n;
			limit -= n;
		}
	}

	spin_unlock(&v9fs_sessionlist_lock);
	return count;
}

static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
#endif /* CONFIG_9P_FSCACHE */

static struct attribute *v9fs_attrs[] = {
#ifdef CONFIG_9P_FSCACHE
	&v9fs_attr_cache.attr,
#endif
	NULL,
};

static struct attribute_group v9fs_attr_group = {
	.attrs = v9fs_attrs,
};

/**
 * v9fs_sysfs_init - Initialize the v9fs sysfs interface
 *
 */

static int v9fs_sysfs_init(void)
{
	v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
	if (!v9fs_kobj)
		return -ENOMEM;

	if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
		kobject_put(v9fs_kobj);
		return -ENOMEM;
	}

	return 0;
}

/**
 * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
 *
 */

static void v9fs_sysfs_cleanup(void)
{
	sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
	kobject_put(v9fs_kobj);
}

/**
 * init_v9fs - Initialize module
 *
 */

static int __init init_v9fs(void)
{
	int err;
	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
	/* TODO: Setup list of registered trasnport modules */
	err = register_filesystem(&v9fs_fs_type);
	if (err < 0) {
		printk(KERN_ERR "Failed to register filesystem\n");
		return err;
	}

	err = v9fs_cache_register();
	if (err < 0) {
		printk(KERN_ERR "Failed to register v9fs for caching\n");
		goto out_fs_unreg;
	}

	err = v9fs_sysfs_init();
	if (err < 0) {
		printk(KERN_ERR "Failed to register with sysfs\n");
		goto out_sysfs_cleanup;
	}

	return 0;

out_sysfs_cleanup:
	v9fs_sysfs_cleanup();

out_fs_unreg:
	unregister_filesystem(&v9fs_fs_type);

	return err;
}

/**
 * exit_v9fs - shutdown module
 *
 */

static void __exit exit_v9fs(void)
{
	v9fs_sysfs_cleanup();
	v9fs_cache_unregister();
	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	32	#include <net/9p/9p.h>
bd238fb4	33	#include <net/9p/client.h>
8b81ef58	34	#include <net/9p/transport.h>
9e82cf6a	35	#include "v9fs.h"
9e82cf6a	36	#include "v9fs_vfs.h"
60e78d2c AK	37	#include "cache.h"
	38
	39	static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
	40	static LIST_HEAD(v9fs_sessionlist);
9e82cf6a EVH	41
9e82cf6a EVH	42	/*
60e78d2c AK	43	* Option Parsing (code inspired by NFS code)
	44	* NOTE: each transport will parse its own options
	45	*/
9e82cf6a EVH	46
	47	enum {
	48	/* Options that take integer arguments */
8a0dc95f	49	Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
9e82cf6a	50	/* String options */
60e78d2c	51	Opt_uname, Opt_remotename, Opt_trans, Opt_cache, Opt_cachetag,
9e82cf6a	52	/* Options that take no arguments */
8a0dc95f	53	Opt_nodevmap,
e03abc0c	54	/* Cache options */
60e78d2c	55	Opt_cache_loose, Opt_fscache,
ba17674f LI	56	/* Access options */
ba17674f LI	57	Opt_access,
9e82cf6a EVH	58	/* Error token */
	59	Opt_err
	60	};
	61
a447c093	62	static const match_table_t tokens = {
9e2f6688	63	{Opt_debug, "debug=%x"},
bd32b82d LI	64	{Opt_dfltuid, "dfltuid=%u"},
bd32b82d LI	65	{Opt_dfltgid, "dfltgid=%u"},
9e82cf6a	66	{Opt_afid, "afid=%u"},
67543e50	67	{Opt_uname, "uname=%s"},
9e82cf6a	68	{Opt_remotename, "aname=%s"},
9e82cf6a	69	{Opt_nodevmap, "nodevmap"},
60e78d2c	70	{Opt_cache, "cache=%s"},
e03abc0c	71	{Opt_cache_loose, "loose"},
60e78d2c AK	72	{Opt_fscache, "fscache"},
60e78d2c AK	73	{Opt_cachetag, "cachetag=%s"},
ba17674f	74	{Opt_access, "access=%s"},
9e82cf6a EVH	75	{Opt_err, NULL}
	76	};
	77
9e82cf6a EVH	78	/**
9e82cf6a EVH	79	* v9fs_parse_options - parse mount options into session structure
9e82cf6a EVH	80	* @v9ses: existing v9fs session information
9e82cf6a EVH	81	*
ab31267d	82	* Return 0 upon success, -ERRNO upon failure.
9e82cf6a EVH	83	*/
9e82cf6a EVH	84
4b53e4b5	85	static int v9fs_parse_options(struct v9fs_session_info v9ses, char opts)
9e82cf6a	86	{
d8c8a9e3	87	char options, tmp_options;
9e82cf6a	88	substring_t args[MAX_OPT_ARGS];
a80d923e	89	char *p;
8a0dc95f	90	int option = 0;
ba17674f	91	char s, e;
ab31267d	92	int ret = 0;
9e82cf6a EVH	93
9e82cf6a EVH	94	/* setup defaults */
9e82cf6a EVH	95	v9ses->afid = ~0;
9e82cf6a EVH	96	v9ses->debug = 0;
e03abc0c	97	v9ses->cache = 0;
60e78d2c AK	98	#ifdef CONFIG_9P_FSCACHE
	99	v9ses->cachetag = NULL;
	100	#endif
9e82cf6a	101
4b53e4b5	102	if (!opts)
ab31267d	103	return 0;
9e82cf6a	104
d8c8a9e3	105	tmp_options = kstrdup(opts, GFP_KERNEL);
bf2d29c6 EVH	106	if (!tmp_options) {
bf2d29c6 EVH	107	ret = -ENOMEM;
60e78d2c	108	goto fail_option_alloc;
bf2d29c6	109	}
d8c8a9e3	110	options = tmp_options;
ab31267d	111
9e82cf6a EVH	112	while ((p = strsep(&options, ",")) != NULL) {
	113	int token;
	114	if (!*p)
	115	continue;
	116	token = match_token(p, tokens, args);
67543e50	117	if (token < Opt_uname) {
ab31267d JM	118	int r = match_int(&args[0], &option);
ab31267d JM	119	if (r < 0) {
bd238fb4	120	P9_DPRINTK(P9_DEBUG_ERROR,
9e82cf6a	121	"integer field, but no integer?\n");
ab31267d	122	ret = r;
9e82cf6a EVH	123	continue;
9e82cf6a EVH	124	}
9e82cf6a EVH	125	}
9e82cf6a EVH	126	switch (token) {
9e2f6688 EVH	127	case Opt_debug:
9e2f6688 EVH	128	v9ses->debug = option;
10fa16e7	129	#ifdef CONFIG_NET_9P_DEBUG
9e2f6688	130	p9_debug_level = option;
10fa16e7	131	#endif
9e2f6688	132	break;
8a0dc95f	133
bd32b82d LI	134	case Opt_dfltuid:
bd32b82d LI	135	v9ses->dfltuid = option;
9e82cf6a	136	break;
bd32b82d LI	137	case Opt_dfltgid:
bd32b82d LI	138	v9ses->dfltgid = option;
9e82cf6a EVH	139	break;
	140	case Opt_afid:
	141	v9ses->afid = option;
	142	break;
67543e50	143	case Opt_uname:
b32a09db	144	match_strlcpy(v9ses->uname, &args[0], PATH_MAX);
9e82cf6a EVH	145	break;
9e82cf6a EVH	146	case Opt_remotename:
b32a09db	147	match_strlcpy(v9ses->aname, &args[0], PATH_MAX);
9e82cf6a	148	break;
9e82cf6a EVH	149	case Opt_nodevmap:
	150	v9ses->nodev = 1;
	151	break;
e03abc0c EVH	152	case Opt_cache_loose:
	153	v9ses->cache = CACHE_LOOSE;
	154	break;
60e78d2c AK	155	case Opt_fscache:
	156	v9ses->cache = CACHE_FSCACHE;
	157	break;
	158	case Opt_cachetag:
	159	#ifdef CONFIG_9P_FSCACHE
	160	v9ses->cachetag = match_strdup(&args[0]);
	161	#endif
	162	break;
	163	case Opt_cache:
	164	s = match_strdup(&args[0]);
bf2d29c6 EVH	165	if (!s) {
	166	ret = -ENOMEM;
	167	P9_DPRINTK(P9_DEBUG_ERROR,
	168	"problem allocating copy of cache arg\n");
	169	goto free_and_return;
	170	}
60e78d2c AK	171
	172	if (strcmp(s, "loose") == 0)
	173	v9ses->cache = CACHE_LOOSE;
	174	else if (strcmp(s, "fscache") == 0)
	175	v9ses->cache = CACHE_FSCACHE;
	176	else
	177	v9ses->cache = CACHE_NONE;
	178	kfree(s);
	179	break;
ba17674f LI	180
	181	case Opt_access:
	182	s = match_strdup(&args[0]);
bf2d29c6 EVH	183	if (!s) {
	184	ret = -ENOMEM;
	185	P9_DPRINTK(P9_DEBUG_ERROR,
	186	"problem allocating copy of access arg\n");
	187	goto free_and_return;
	188	}
60e78d2c	189
ba17674f LI	190	v9ses->flags &= ~V9FS_ACCESS_MASK;
	191	if (strcmp(s, "user") == 0)
	192	v9ses->flags \|= V9FS_ACCESS_USER;
	193	else if (strcmp(s, "any") == 0)
	194	v9ses->flags \|= V9FS_ACCESS_ANY;
	195	else {
	196	v9ses->flags \|= V9FS_ACCESS_SINGLE;
f1d9e458	197	v9ses->uid = simple_strtoul(s, &e, 10);
ba17674f LI	198	if (*e != '\0')
	199	v9ses->uid = ~0;
	200	}
0a976297	201	kfree(s);
ba17674f LI	202	break;
ba17674f LI	203
9e82cf6a EVH	204	default:
	205	continue;
	206	}
	207	}
d8c8a9e3	208
bf2d29c6	209	free_and_return:
d8c8a9e3	210	kfree(tmp_options);
60e78d2c	211	fail_option_alloc:
bf2d29c6	212	return ret;
9e82cf6a EVH	213	}
9e82cf6a EVH	214
9e82cf6a EVH	215	/**
	216	* v9fs_session_init - initialize session
	217	* @v9ses: session information structure
	218	* @dev_name: device being mounted
	219	* @data: options
	220	*
	221	*/
	222
bd238fb4	223	struct p9_fid v9fs_session_init(struct v9fs_session_info v9ses,
9e82cf6a EVH	224	const char dev_name, char data)
9e82cf6a EVH	225	{
9e82cf6a	226	int retval = -EINVAL;
bd238fb4	227	struct p9_fid *fid;
ab31267d	228	int rc;
9e82cf6a	229
ba17674f LI	230	v9ses->uname = __getname();
ba17674f LI	231	if (!v9ses->uname)
bd238fb4	232	return ERR_PTR(-ENOMEM);
9e82cf6a	233
ba17674f LI	234	v9ses->aname = __getname();
	235	if (!v9ses->aname) {
	236	__putname(v9ses->uname);
bd238fb4	237	return ERR_PTR(-ENOMEM);
9e82cf6a EVH	238	}
9e82cf6a EVH	239
60e78d2c AK	240	spin_lock(&v9fs_sessionlist_lock);
	241	list_add(&v9ses->slist, &v9fs_sessionlist);
	242	spin_unlock(&v9fs_sessionlist_lock);
	243
476ada04	244	v9ses->flags = V9FS_ACCESS_USER;
ba17674f LI	245	strcpy(v9ses->uname, V9FS_DEFUSER);
	246	strcpy(v9ses->aname, V9FS_DEFANAME);
	247	v9ses->uid = ~0;
bd32b82d LI	248	v9ses->dfltuid = V9FS_DEFUID;
bd32b82d LI	249	v9ses->dfltgid = V9FS_DEFGID;
ab31267d	250
4b53e4b5	251	rc = v9fs_parse_options(v9ses, data);
ab31267d JM	252	if (rc < 0) {
	253	retval = rc;
	254	goto error;
	255	}
a80d923e	256
4b53e4b5	257	v9ses->clnt = p9_client_create(dev_name, data);
bd238fb4 LI	258	if (IS_ERR(v9ses->clnt)) {
	259	retval = PTR_ERR(v9ses->clnt);
	260	v9ses->clnt = NULL;
	261	P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
	262	goto error;
9e82cf6a EVH	263	}
9e82cf6a EVH	264
476ada04 SK	265	if (p9_is_proto_dotl(v9ses->clnt))
	266	v9ses->flags \|= V9FS_PROTO_2000L;
	267	else if (p9_is_proto_dotu(v9ses->clnt))
	268	v9ses->flags \|= V9FS_PROTO_2000U;
ba17674f	269
fbedadc1	270	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
8a0dc95f	271
ba17674f	272	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
dd6102fb	273	if (!v9fs_proto_dotu(v9ses) &&
ba17674f LI	274	((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
	275
	276	v9ses->flags &= ~V9FS_ACCESS_MASK;
	277	v9ses->flags \|= V9FS_ACCESS_ANY;
	278	v9ses->uid = ~0;
	279	}
	280
	281	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
	282	v9ses->aname);
bd238fb4 LI	283	if (IS_ERR(fid)) {
	284	retval = PTR_ERR(fid);
	285	fid = NULL;
	286	P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
	287	goto error;
9e82cf6a EVH	288	}
9e82cf6a EVH	289
ba17674f LI	290	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
	291	fid->uid = v9ses->uid;
	292	else
	293	fid->uid = ~0;
	294
60e78d2c AK	295	#ifdef CONFIG_9P_FSCACHE
	296	/* register the session for caching */
	297	v9fs_cache_session_get_cookie(v9ses);
	298	#endif
	299
bd238fb4	300	return fid;
9e82cf6a	301
bd238fb4	302	error:
bd238fb4	303	return ERR_PTR(retval);
9e82cf6a EVH	304	}
	305
	306	/**
	307	* v9fs_session_close - shutdown a session
	308	* @v9ses: session information structure
	309	*
	310	*/
	311
	312	void v9fs_session_close(struct v9fs_session_info *v9ses)
	313	{
bd238fb4 LI	314	if (v9ses->clnt) {
	315	p9_client_destroy(v9ses->clnt);
	316	v9ses->clnt = NULL;
3cf6429a	317	}
9e82cf6a	318
60e78d2c AK	319	#ifdef CONFIG_9P_FSCACHE
	320	if (v9ses->fscache) {
	321	v9fs_cache_session_put_cookie(v9ses);
	322	kfree(v9ses->cachetag);
	323	}
	324	#endif
ba17674f LI	325	__putname(v9ses->uname);
ba17674f LI	326	__putname(v9ses->aname);
60e78d2c AK	327
	328	spin_lock(&v9fs_sessionlist_lock);
	329	list_del(&v9ses->slist);
	330	spin_unlock(&v9fs_sessionlist_lock);
9e82cf6a EVH	331	}
9e82cf6a EVH	332
322b329a	333	/**
ee443996 EVH	334	* v9fs_session_cancel - terminate a session
	335	* @v9ses: session to terminate
	336	*
	337	* mark transport as disconnected and cancel all pending requests.
322b329a	338	*/
ee443996	339
322b329a	340	void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
bd238fb4 LI	341	P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
bd238fb4 LI	342	p9_client_disconnect(v9ses->clnt);
322b329a EVH	343	}
322b329a EVH	344
9e82cf6a EVH	345	extern int v9fs_error_init(void);
9e82cf6a EVH	346
60e78d2c AK	347	static struct kobject *v9fs_kobj;
	348
	349	#ifdef CONFIG_9P_FSCACHE
9e82cf6a	350	/**
60e78d2c AK	351	* caches_show - list caches associated with a session
	352	*
	353	* Returns the size of buffer written.
	354	*/
	355
	356	static ssize_t caches_show(struct kobject *kobj,
	357	struct kobj_attribute *attr,
	358	char *buf)
	359	{
	360	ssize_t n = 0, count = 0, limit = PAGE_SIZE;
	361	struct v9fs_session_info *v9ses;
	362
	363	spin_lock(&v9fs_sessionlist_lock);
	364	list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
	365	if (v9ses->cachetag) {
	366	n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
	367	if (n < 0) {
	368	count = n;
	369	break;
	370	}
	371
	372	count += n;
	373	limit -= n;
	374	}
	375	}
	376
	377	spin_unlock(&v9fs_sessionlist_lock);
	378	return count;
	379	}
	380
	381	static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
	382	#endif /* CONFIG_9P_FSCACHE */
	383
	384	static struct attribute *v9fs_attrs[] = {
	385	#ifdef CONFIG_9P_FSCACHE
	386	&v9fs_attr_cache.attr,
	387	#endif
	388	NULL,
	389	};
	390
	391	static struct attribute_group v9fs_attr_group = {
	392	.attrs = v9fs_attrs,
	393	};
	394
	395	/**
	396	* v9fs_sysfs_init - Initialize the v9fs sysfs interface
	397	*
	398	*/
	399
	400	static int v9fs_sysfs_init(void)
	401	{
	402	v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
	403	if (!v9fs_kobj)
	404	return -ENOMEM;
	405
	406	if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
	407	kobject_put(v9fs_kobj);
	408	return -ENOMEM;
	409	}
	410
	411	return 0;
	412	}
	413
	414	/**
415	* v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
416	*
417	*/
418
419	static void v9fs_sysfs_cleanup(void)
420	{
421	sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
422	kobject_put(v9fs_kobj);
423	}
424
425	/**
426	* init_v9fs - Initialize module
9e82cf6a EVH	427	*
	428	*/
	429
	430	static int __init init_v9fs(void)
	431	{
60e78d2c	432	int err;
f94b3470	433	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
a80d923e	434	/* TODO: Setup list of registered trasnport modules */
60e78d2c AK	435	err = register_filesystem(&v9fs_fs_type);
	436	if (err < 0) {
	437	printk(KERN_ERR "Failed to register filesystem\n");
	438	return err;
	439	}
	440
	441	err = v9fs_cache_register();
	442	if (err < 0) {
	443	printk(KERN_ERR "Failed to register v9fs for caching\n");
	444	goto out_fs_unreg;
	445	}
	446
	447	err = v9fs_sysfs_init();
	448	if (err < 0) {
	449	printk(KERN_ERR "Failed to register with sysfs\n");
	450	goto out_sysfs_cleanup;
	451	}
	452
	453	return 0;
	454
	455	out_sysfs_cleanup:
	456	v9fs_sysfs_cleanup();
	457
	458	out_fs_unreg:
	459	unregister_filesystem(&v9fs_fs_type);
	460
	461	return err;
9e82cf6a EVH	462	}
	463
	464	/**
60e78d2c	465	* exit_v9fs - shutdown module
9e82cf6a EVH	466	*
	467	*/
	468
	469	static void __exit exit_v9fs(void)
	470	{
60e78d2c AK	471	v9fs_sysfs_cleanup();
60e78d2c AK	472	v9fs_cache_unregister();
9e82cf6a EVH	473	unregister_filesystem(&v9fs_fs_type);
	474	}
	475
	476	module_init(init_v9fs)
	477	module_exit(exit_v9fs)
	478
bd238fb4	479	MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
9e82cf6a EVH	480	MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
	481	MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
	482	MODULE_LICENSE("GPL");