[mirror_ubuntu-bionic-kernel.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)
		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)
				goto fail_option_alloc;

			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)
				goto fail_option_alloc;

			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;
		}
	}

	kfree(tmp_options);
	return ret;

fail_option_alloc:
	P9_DPRINTK(P9_DEBUG_ERROR,
		   "failed to allocate copy of option argument\n");
	return -ENOMEM;
}

/**
 * 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_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;

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

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

	/* 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;

#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 EVH	105	tmp_options = kstrdup(opts, GFP_KERNEL);
d8c8a9e3 EVH	106	if (!tmp_options)
60e78d2c	107	goto fail_option_alloc;
d8c8a9e3	108	options = tmp_options;
ab31267d	109
9e82cf6a EVH	110	while ((p = strsep(&options, ",")) != NULL) {
	111	int token;
	112	if (!*p)
	113	continue;
	114	token = match_token(p, tokens, args);
67543e50	115	if (token < Opt_uname) {
ab31267d JM	116	int r = match_int(&args[0], &option);
ab31267d JM	117	if (r < 0) {
bd238fb4	118	P9_DPRINTK(P9_DEBUG_ERROR,
9e82cf6a	119	"integer field, but no integer?\n");
ab31267d	120	ret = r;
9e82cf6a EVH	121	continue;
9e82cf6a EVH	122	}
9e82cf6a EVH	123	}
9e82cf6a EVH	124	switch (token) {
9e2f6688 EVH	125	case Opt_debug:
9e2f6688 EVH	126	v9ses->debug = option;
10fa16e7	127	#ifdef CONFIG_NET_9P_DEBUG
9e2f6688	128	p9_debug_level = option;
10fa16e7	129	#endif
9e2f6688	130	break;
8a0dc95f	131
bd32b82d LI	132	case Opt_dfltuid:
bd32b82d LI	133	v9ses->dfltuid = option;
9e82cf6a	134	break;
bd32b82d LI	135	case Opt_dfltgid:
bd32b82d LI	136	v9ses->dfltgid = option;
9e82cf6a EVH	137	break;
	138	case Opt_afid:
	139	v9ses->afid = option;
	140	break;
67543e50	141	case Opt_uname:
b32a09db	142	match_strlcpy(v9ses->uname, &args[0], PATH_MAX);
9e82cf6a EVH	143	break;
9e82cf6a EVH	144	case Opt_remotename:
b32a09db	145	match_strlcpy(v9ses->aname, &args[0], PATH_MAX);
9e82cf6a	146	break;
9e82cf6a EVH	147	case Opt_nodevmap:
	148	v9ses->nodev = 1;
	149	break;
e03abc0c EVH	150	case Opt_cache_loose:
	151	v9ses->cache = CACHE_LOOSE;
	152	break;
60e78d2c AK	153	case Opt_fscache:
	154	v9ses->cache = CACHE_FSCACHE;
	155	break;
	156	case Opt_cachetag:
	157	#ifdef CONFIG_9P_FSCACHE
	158	v9ses->cachetag = match_strdup(&args[0]);
	159	#endif
	160	break;
	161	case Opt_cache:
	162	s = match_strdup(&args[0]);
	163	if (!s)
	164	goto fail_option_alloc;
	165
	166	if (strcmp(s, "loose") == 0)
	167	v9ses->cache = CACHE_LOOSE;
	168	else if (strcmp(s, "fscache") == 0)
	169	v9ses->cache = CACHE_FSCACHE;
	170	else
	171	v9ses->cache = CACHE_NONE;
	172	kfree(s);
	173	break;
ba17674f LI	174
	175	case Opt_access:
	176	s = match_strdup(&args[0]);
60e78d2c AK	177	if (!s)
	178	goto fail_option_alloc;
	179
ba17674f LI	180	v9ses->flags &= ~V9FS_ACCESS_MASK;
	181	if (strcmp(s, "user") == 0)
	182	v9ses->flags \|= V9FS_ACCESS_USER;
	183	else if (strcmp(s, "any") == 0)
	184	v9ses->flags \|= V9FS_ACCESS_ANY;
	185	else {
	186	v9ses->flags \|= V9FS_ACCESS_SINGLE;
f1d9e458	187	v9ses->uid = simple_strtoul(s, &e, 10);
ba17674f LI	188	if (*e != '\0')
	189	v9ses->uid = ~0;
	190	}
0a976297	191	kfree(s);
ba17674f LI	192	break;
ba17674f LI	193
9e82cf6a EVH	194	default:
	195	continue;
	196	}
	197	}
d8c8a9e3 EVH	198
d8c8a9e3 EVH	199	kfree(tmp_options);
ab31267d	200	return ret;
60e78d2c AK	201
	202	fail_option_alloc:
	203	P9_DPRINTK(P9_DEBUG_ERROR,
	204	"failed to allocate copy of option argument\n");
	205	return -ENOMEM;
9e82cf6a EVH	206	}
9e82cf6a EVH	207
9e82cf6a EVH	208	/**
	209	* v9fs_session_init - initialize session
	210	* @v9ses: session information structure
	211	* @dev_name: device being mounted
	212	* @data: options
	213	*
	214	*/
	215
bd238fb4	216	struct p9_fid v9fs_session_init(struct v9fs_session_info v9ses,
9e82cf6a EVH	217	const char dev_name, char data)
9e82cf6a EVH	218	{
9e82cf6a	219	int retval = -EINVAL;
bd238fb4	220	struct p9_fid *fid;
ab31267d	221	int rc;
9e82cf6a	222
ba17674f LI	223	v9ses->uname = __getname();
ba17674f LI	224	if (!v9ses->uname)
bd238fb4	225	return ERR_PTR(-ENOMEM);
9e82cf6a	226
ba17674f LI	227	v9ses->aname = __getname();
	228	if (!v9ses->aname) {
	229	__putname(v9ses->uname);
bd238fb4	230	return ERR_PTR(-ENOMEM);
9e82cf6a EVH	231	}
9e82cf6a EVH	232
60e78d2c AK	233	spin_lock(&v9fs_sessionlist_lock);
	234	list_add(&v9ses->slist, &v9fs_sessionlist);
	235	spin_unlock(&v9fs_sessionlist_lock);
	236
ba17674f LI	237	v9ses->flags = V9FS_EXTENDED \| V9FS_ACCESS_USER;
	238	strcpy(v9ses->uname, V9FS_DEFUSER);
	239	strcpy(v9ses->aname, V9FS_DEFANAME);
	240	v9ses->uid = ~0;
bd32b82d LI	241	v9ses->dfltuid = V9FS_DEFUID;
bd32b82d LI	242	v9ses->dfltgid = V9FS_DEFGID;
ab31267d	243
4b53e4b5	244	rc = v9fs_parse_options(v9ses, data);
ab31267d JM	245	if (rc < 0) {
	246	retval = rc;
	247	goto error;
	248	}
a80d923e	249
4b53e4b5	250	v9ses->clnt = p9_client_create(dev_name, data);
bd238fb4 LI	251	if (IS_ERR(v9ses->clnt)) {
	252	retval = PTR_ERR(v9ses->clnt);
	253	v9ses->clnt = NULL;
	254	P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
	255	goto error;
9e82cf6a EVH	256	}
9e82cf6a EVH	257
ba17674f LI	258	if (!v9ses->clnt->dotu)
	259	v9ses->flags &= ~V9FS_EXTENDED;
	260
fbedadc1	261	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
8a0dc95f	262
ba17674f LI	263	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
	264	if (!v9fs_extended(v9ses) &&
	265	((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
	266
	267	v9ses->flags &= ~V9FS_ACCESS_MASK;
	268	v9ses->flags \|= V9FS_ACCESS_ANY;
	269	v9ses->uid = ~0;
	270	}
	271
	272	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
	273	v9ses->aname);
bd238fb4 LI	274	if (IS_ERR(fid)) {
	275	retval = PTR_ERR(fid);
	276	fid = NULL;
	277	P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
	278	goto error;
9e82cf6a EVH	279	}
9e82cf6a EVH	280
ba17674f LI	281	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
	282	fid->uid = v9ses->uid;
	283	else
	284	fid->uid = ~0;
	285
60e78d2c AK	286	#ifdef CONFIG_9P_FSCACHE
	287	/* register the session for caching */
	288	v9fs_cache_session_get_cookie(v9ses);
	289	#endif
	290
bd238fb4	291	return fid;
9e82cf6a	292
bd238fb4	293	error:
bd238fb4	294	return ERR_PTR(retval);
9e82cf6a EVH	295	}
	296
	297	/**
	298	* v9fs_session_close - shutdown a session
	299	* @v9ses: session information structure
	300	*
	301	*/
	302
	303	void v9fs_session_close(struct v9fs_session_info *v9ses)
	304	{
bd238fb4 LI	305	if (v9ses->clnt) {
	306	p9_client_destroy(v9ses->clnt);
	307	v9ses->clnt = NULL;
3cf6429a	308	}
9e82cf6a	309
60e78d2c AK	310	#ifdef CONFIG_9P_FSCACHE
	311	if (v9ses->fscache) {
	312	v9fs_cache_session_put_cookie(v9ses);
	313	kfree(v9ses->cachetag);
	314	}
	315	#endif
ba17674f LI	316	__putname(v9ses->uname);
ba17674f LI	317	__putname(v9ses->aname);
60e78d2c AK	318
	319	spin_lock(&v9fs_sessionlist_lock);
	320	list_del(&v9ses->slist);
	321	spin_unlock(&v9fs_sessionlist_lock);
9e82cf6a EVH	322	}
9e82cf6a EVH	323
322b329a	324	/**
ee443996 EVH	325	* v9fs_session_cancel - terminate a session
	326	* @v9ses: session to terminate
	327	*
	328	* mark transport as disconnected and cancel all pending requests.
322b329a	329	*/
ee443996	330
322b329a	331	void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
bd238fb4 LI	332	P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
bd238fb4 LI	333	p9_client_disconnect(v9ses->clnt);
322b329a EVH	334	}
322b329a EVH	335
9e82cf6a EVH	336	extern int v9fs_error_init(void);
9e82cf6a EVH	337
60e78d2c AK	338	static struct kobject *v9fs_kobj;
	339
	340	#ifdef CONFIG_9P_FSCACHE
9e82cf6a	341	/**
60e78d2c AK	342	* caches_show - list caches associated with a session
	343	*
	344	* Returns the size of buffer written.
	345	*/
	346
	347	static ssize_t caches_show(struct kobject *kobj,
	348	struct kobj_attribute *attr,
	349	char *buf)
	350	{
	351	ssize_t n = 0, count = 0, limit = PAGE_SIZE;
	352	struct v9fs_session_info *v9ses;
	353
	354	spin_lock(&v9fs_sessionlist_lock);
	355	list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
	356	if (v9ses->cachetag) {
	357	n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
	358	if (n < 0) {
	359	count = n;
	360	break;
	361	}
	362
	363	count += n;
	364	limit -= n;
	365	}
	366	}
	367
	368	spin_unlock(&v9fs_sessionlist_lock);
	369	return count;
	370	}
	371
	372	static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
	373	#endif /* CONFIG_9P_FSCACHE */
	374
	375	static struct attribute *v9fs_attrs[] = {
	376	#ifdef CONFIG_9P_FSCACHE
	377	&v9fs_attr_cache.attr,
	378	#endif
	379	NULL,
	380	};
	381
	382	static struct attribute_group v9fs_attr_group = {
	383	.attrs = v9fs_attrs,
	384	};
	385
	386	/**
	387	* v9fs_sysfs_init - Initialize the v9fs sysfs interface
	388	*
	389	*/
	390
	391	static int v9fs_sysfs_init(void)
	392	{
	393	v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
	394	if (!v9fs_kobj)
	395	return -ENOMEM;
	396
	397	if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
	398	kobject_put(v9fs_kobj);
	399	return -ENOMEM;
	400	}
	401
	402	return 0;
	403	}
	404
	405	/**
406	* v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
407	*
408	*/
409
410	static void v9fs_sysfs_cleanup(void)
411	{
412	sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
413	kobject_put(v9fs_kobj);
414	}
415
416	/**
417	* init_v9fs - Initialize module
9e82cf6a EVH	418	*
	419	*/
	420
	421	static int __init init_v9fs(void)
	422	{
60e78d2c	423	int err;
f94b3470	424	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
a80d923e	425	/* TODO: Setup list of registered trasnport modules */
60e78d2c AK	426	err = register_filesystem(&v9fs_fs_type);
	427	if (err < 0) {
	428	printk(KERN_ERR "Failed to register filesystem\n");
	429	return err;
	430	}
	431
	432	err = v9fs_cache_register();
	433	if (err < 0) {
	434	printk(KERN_ERR "Failed to register v9fs for caching\n");
	435	goto out_fs_unreg;
	436	}
	437
	438	err = v9fs_sysfs_init();
	439	if (err < 0) {
	440	printk(KERN_ERR "Failed to register with sysfs\n");
	441	goto out_sysfs_cleanup;
	442	}
	443
	444	return 0;
	445
	446	out_sysfs_cleanup:
	447	v9fs_sysfs_cleanup();
	448
	449	out_fs_unreg:
	450	unregister_filesystem(&v9fs_fs_type);
	451
	452	return err;
9e82cf6a EVH	453	}
	454
	455	/**
60e78d2c	456	* exit_v9fs - shutdown module
9e82cf6a EVH	457	*
	458	*/
	459
	460	static void __exit exit_v9fs(void)
	461	{
60e78d2c AK	462	v9fs_sysfs_cleanup();
60e78d2c AK	463	v9fs_cache_unregister();
9e82cf6a EVH	464	unregister_filesystem(&v9fs_fs_type);
	465	}
	466
	467	module_init(init_v9fs)
	468	module_exit(exit_v9fs)
	469
bd238fb4	470	MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
9e82cf6a EVH	471	MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
	472	MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
	473	MODULE_LICENSE("GPL");