[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 <linux/slab.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 if (strcmp(s, "client") == 0) {
#ifdef CONFIG_9P_FS_POSIX_ACL
				v9ses->flags |= V9FS_ACCESS_CLIENT;
#else
				P9_DPRINTK(P9_DEBUG_ERROR,
					"access=client option not supported\n");
				kfree(s);
				ret = -EINVAL;
				goto free_and_return;
#endif
			} 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);
	}
	init_rwsem(&v9ses->rename_sem);

	rc = bdi_setup_and_register(&v9ses->bdi, "9p", BDI_CAP_MAP_COPY);
	if (rc) {
		__putname(v9ses->aname);
		__putname(v9ses->uname);
		return ERR_PTR(rc);
	}

	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;

	if (!v9fs_proto_dotl(v9ses) &&
	    ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
		/*
		 * We support ACCESS_CLIENT only for dotl.
		 * Fall back to ACCESS_USER
		 */
		v9ses->flags &= ~V9FS_ACCESS_MASK;
		v9ses->flags |= V9FS_ACCESS_USER;
	}
	/*FIXME !! */
	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
	if (!(v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(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:
	bdi_destroy(&v9ses->bdi);
	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);

	bdi_destroy(&v9ses->bdi);

	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);
}

/**
 * v9fs_session_begin_cancel - Begin terminate of a session
 * @v9ses: session to terminate
 *
 * After this call we don't allow any request other than clunk.
 */

void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
{
	P9_DPRINTK(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
	p9_client_begin_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>
5a0e3ad6	32	#include <linux/slab.h>
bd238fb4	33	#include <net/9p/9p.h>
bd238fb4	34	#include <net/9p/client.h>
8b81ef58	35	#include <net/9p/transport.h>
9e82cf6a	36	#include "v9fs.h"
9e82cf6a	37	#include "v9fs_vfs.h"
60e78d2c AK	38	#include "cache.h"
	39
	40	static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
	41	static LIST_HEAD(v9fs_sessionlist);
9e82cf6a EVH	42
9e82cf6a EVH	43	/*
60e78d2c AK	44	* Option Parsing (code inspired by NFS code)
	45	* NOTE: each transport will parse its own options
	46	*/
9e82cf6a EVH	47
	48	enum {
	49	/* Options that take integer arguments */
8a0dc95f	50	Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
9e82cf6a	51	/* String options */
60e78d2c	52	Opt_uname, Opt_remotename, Opt_trans, Opt_cache, Opt_cachetag,
9e82cf6a	53	/* Options that take no arguments */
8a0dc95f	54	Opt_nodevmap,
e03abc0c	55	/* Cache options */
60e78d2c	56	Opt_cache_loose, Opt_fscache,
ba17674f LI	57	/* Access options */
ba17674f LI	58	Opt_access,
9e82cf6a EVH	59	/* Error token */
	60	Opt_err
	61	};
	62
a447c093	63	static const match_table_t tokens = {
9e2f6688	64	{Opt_debug, "debug=%x"},
bd32b82d LI	65	{Opt_dfltuid, "dfltuid=%u"},
bd32b82d LI	66	{Opt_dfltgid, "dfltgid=%u"},
9e82cf6a	67	{Opt_afid, "afid=%u"},
67543e50	68	{Opt_uname, "uname=%s"},
9e82cf6a	69	{Opt_remotename, "aname=%s"},
9e82cf6a	70	{Opt_nodevmap, "nodevmap"},
60e78d2c	71	{Opt_cache, "cache=%s"},
e03abc0c	72	{Opt_cache_loose, "loose"},
60e78d2c AK	73	{Opt_fscache, "fscache"},
60e78d2c AK	74	{Opt_cachetag, "cachetag=%s"},
ba17674f	75	{Opt_access, "access=%s"},
9e82cf6a EVH	76	{Opt_err, NULL}
	77	};
	78
9e82cf6a EVH	79	/**
9e82cf6a EVH	80	* v9fs_parse_options - parse mount options into session structure
9e82cf6a EVH	81	* @v9ses: existing v9fs session information
9e82cf6a EVH	82	*
ab31267d	83	* Return 0 upon success, -ERRNO upon failure.
9e82cf6a EVH	84	*/
9e82cf6a EVH	85
4b53e4b5	86	static int v9fs_parse_options(struct v9fs_session_info v9ses, char opts)
9e82cf6a	87	{
d8c8a9e3	88	char options, tmp_options;
9e82cf6a	89	substring_t args[MAX_OPT_ARGS];
a80d923e	90	char *p;
8a0dc95f	91	int option = 0;
ba17674f	92	char s, e;
ab31267d	93	int ret = 0;
9e82cf6a EVH	94
9e82cf6a EVH	95	/* setup defaults */
9e82cf6a EVH	96	v9ses->afid = ~0;
9e82cf6a EVH	97	v9ses->debug = 0;
e03abc0c	98	v9ses->cache = 0;
60e78d2c AK	99	#ifdef CONFIG_9P_FSCACHE
	100	v9ses->cachetag = NULL;
	101	#endif
9e82cf6a	102
4b53e4b5	103	if (!opts)
ab31267d	104	return 0;
9e82cf6a	105
d8c8a9e3	106	tmp_options = kstrdup(opts, GFP_KERNEL);
bf2d29c6 EVH	107	if (!tmp_options) {
bf2d29c6 EVH	108	ret = -ENOMEM;
60e78d2c	109	goto fail_option_alloc;
bf2d29c6	110	}
d8c8a9e3	111	options = tmp_options;
ab31267d	112
9e82cf6a EVH	113	while ((p = strsep(&options, ",")) != NULL) {
	114	int token;
	115	if (!*p)
	116	continue;
	117	token = match_token(p, tokens, args);
67543e50	118	if (token < Opt_uname) {
ab31267d JM	119	int r = match_int(&args[0], &option);
ab31267d JM	120	if (r < 0) {
bd238fb4	121	P9_DPRINTK(P9_DEBUG_ERROR,
9e82cf6a	122	"integer field, but no integer?\n");
ab31267d	123	ret = r;
9e82cf6a EVH	124	continue;
9e82cf6a EVH	125	}
9e82cf6a EVH	126	}
9e82cf6a EVH	127	switch (token) {
9e2f6688 EVH	128	case Opt_debug:
9e2f6688 EVH	129	v9ses->debug = option;
10fa16e7	130	#ifdef CONFIG_NET_9P_DEBUG
9e2f6688	131	p9_debug_level = option;
10fa16e7	132	#endif
9e2f6688	133	break;
8a0dc95f	134
bd32b82d LI	135	case Opt_dfltuid:
bd32b82d LI	136	v9ses->dfltuid = option;
9e82cf6a	137	break;
bd32b82d LI	138	case Opt_dfltgid:
bd32b82d LI	139	v9ses->dfltgid = option;
9e82cf6a EVH	140	break;
	141	case Opt_afid:
	142	v9ses->afid = option;
	143	break;
67543e50	144	case Opt_uname:
b32a09db	145	match_strlcpy(v9ses->uname, &args[0], PATH_MAX);
9e82cf6a EVH	146	break;
9e82cf6a EVH	147	case Opt_remotename:
b32a09db	148	match_strlcpy(v9ses->aname, &args[0], PATH_MAX);
9e82cf6a	149	break;
9e82cf6a EVH	150	case Opt_nodevmap:
	151	v9ses->nodev = 1;
	152	break;
e03abc0c EVH	153	case Opt_cache_loose:
	154	v9ses->cache = CACHE_LOOSE;
	155	break;
60e78d2c AK	156	case Opt_fscache:
	157	v9ses->cache = CACHE_FSCACHE;
	158	break;
	159	case Opt_cachetag:
	160	#ifdef CONFIG_9P_FSCACHE
	161	v9ses->cachetag = match_strdup(&args[0]);
	162	#endif
	163	break;
	164	case Opt_cache:
	165	s = match_strdup(&args[0]);
bf2d29c6 EVH	166	if (!s) {
	167	ret = -ENOMEM;
	168	P9_DPRINTK(P9_DEBUG_ERROR,
	169	"problem allocating copy of cache arg\n");
	170	goto free_and_return;
	171	}
60e78d2c AK	172
	173	if (strcmp(s, "loose") == 0)
	174	v9ses->cache = CACHE_LOOSE;
	175	else if (strcmp(s, "fscache") == 0)
	176	v9ses->cache = CACHE_FSCACHE;
	177	else
	178	v9ses->cache = CACHE_NONE;
	179	kfree(s);
	180	break;
ba17674f LI	181
	182	case Opt_access:
	183	s = match_strdup(&args[0]);
bf2d29c6 EVH	184	if (!s) {
	185	ret = -ENOMEM;
	186	P9_DPRINTK(P9_DEBUG_ERROR,
	187	"problem allocating copy of access arg\n");
	188	goto free_and_return;
	189	}
60e78d2c	190
ba17674f LI	191	v9ses->flags &= ~V9FS_ACCESS_MASK;
	192	if (strcmp(s, "user") == 0)
	193	v9ses->flags \|= V9FS_ACCESS_USER;
	194	else if (strcmp(s, "any") == 0)
	195	v9ses->flags \|= V9FS_ACCESS_ANY;
76381a42 AK	196	else if (strcmp(s, "client") == 0) {
	197	#ifdef CONFIG_9P_FS_POSIX_ACL
	198	v9ses->flags \|= V9FS_ACCESS_CLIENT;
	199	#else
	200	P9_DPRINTK(P9_DEBUG_ERROR,
	201	"access=client option not supported\n");
	202	kfree(s);
	203	ret = -EINVAL;
	204	goto free_and_return;
	205	#endif
	206	} else {
ba17674f	207	v9ses->flags \|= V9FS_ACCESS_SINGLE;
f1d9e458	208	v9ses->uid = simple_strtoul(s, &e, 10);
ba17674f LI	209	if (*e != '\0')
	210	v9ses->uid = ~0;
	211	}
0a976297	212	kfree(s);
ba17674f LI	213	break;
ba17674f LI	214
9e82cf6a EVH	215	default:
	216	continue;
	217	}
	218	}
d8c8a9e3	219
bf2d29c6	220	free_and_return:
d8c8a9e3	221	kfree(tmp_options);
60e78d2c	222	fail_option_alloc:
bf2d29c6	223	return ret;
9e82cf6a EVH	224	}
9e82cf6a EVH	225
9e82cf6a EVH	226	/**
	227	* v9fs_session_init - initialize session
	228	* @v9ses: session information structure
	229	* @dev_name: device being mounted
	230	* @data: options
	231	*
	232	*/
	233
bd238fb4	234	struct p9_fid v9fs_session_init(struct v9fs_session_info v9ses,
9e82cf6a EVH	235	const char dev_name, char data)
9e82cf6a EVH	236	{
9e82cf6a	237	int retval = -EINVAL;
bd238fb4	238	struct p9_fid *fid;
ab31267d	239	int rc;
9e82cf6a	240
ba17674f LI	241	v9ses->uname = __getname();
ba17674f LI	242	if (!v9ses->uname)
bd238fb4	243	return ERR_PTR(-ENOMEM);
9e82cf6a	244
ba17674f LI	245	v9ses->aname = __getname();
	246	if (!v9ses->aname) {
	247	__putname(v9ses->uname);
bd238fb4	248	return ERR_PTR(-ENOMEM);
9e82cf6a	249	}
a534c8d1	250	init_rwsem(&v9ses->rename_sem);
9e82cf6a	251
0ed07ddb JA	252	rc = bdi_setup_and_register(&v9ses->bdi, "9p", BDI_CAP_MAP_COPY);
	253	if (rc) {
	254	__putname(v9ses->aname);
	255	__putname(v9ses->uname);
	256	return ERR_PTR(rc);
	257	}
	258
60e78d2c AK	259	spin_lock(&v9fs_sessionlist_lock);
	260	list_add(&v9ses->slist, &v9fs_sessionlist);
	261	spin_unlock(&v9fs_sessionlist_lock);
	262
476ada04	263	v9ses->flags = V9FS_ACCESS_USER;
ba17674f LI	264	strcpy(v9ses->uname, V9FS_DEFUSER);
	265	strcpy(v9ses->aname, V9FS_DEFANAME);
	266	v9ses->uid = ~0;
bd32b82d LI	267	v9ses->dfltuid = V9FS_DEFUID;
bd32b82d LI	268	v9ses->dfltgid = V9FS_DEFGID;
ab31267d	269
4b53e4b5	270	rc = v9fs_parse_options(v9ses, data);
ab31267d JM	271	if (rc < 0) {
	272	retval = rc;
	273	goto error;
	274	}
a80d923e	275
4b53e4b5	276	v9ses->clnt = p9_client_create(dev_name, data);
bd238fb4 LI	277	if (IS_ERR(v9ses->clnt)) {
	278	retval = PTR_ERR(v9ses->clnt);
	279	v9ses->clnt = NULL;
	280	P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
	281	goto error;
9e82cf6a EVH	282	}
9e82cf6a EVH	283
476ada04 SK	284	if (p9_is_proto_dotl(v9ses->clnt))
	285	v9ses->flags \|= V9FS_PROTO_2000L;
	286	else if (p9_is_proto_dotu(v9ses->clnt))
	287	v9ses->flags \|= V9FS_PROTO_2000U;
ba17674f	288
fbedadc1	289	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
8a0dc95f	290
76381a42 AK	291	if (!v9fs_proto_dotl(v9ses) &&
	292	((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
	293	/*
	294	* We support ACCESS_CLIENT only for dotl.
	295	* Fall back to ACCESS_USER
	296	*/
	297	v9ses->flags &= ~V9FS_ACCESS_MASK;
	298	v9ses->flags \|= V9FS_ACCESS_USER;
	299	}
	300	/FIXME !! /
ba17674f	301	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
9ffaf63e	302	if (!(v9fs_proto_dotu(v9ses) \|\| v9fs_proto_dotl(v9ses)) &&
ba17674f LI	303	((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
	304
	305	v9ses->flags &= ~V9FS_ACCESS_MASK;
	306	v9ses->flags \|= V9FS_ACCESS_ANY;
	307	v9ses->uid = ~0;
	308	}
	309
	310	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
	311	v9ses->aname);
bd238fb4 LI	312	if (IS_ERR(fid)) {
	313	retval = PTR_ERR(fid);
	314	fid = NULL;
	315	P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
	316	goto error;
9e82cf6a EVH	317	}
9e82cf6a EVH	318
ba17674f LI	319	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
	320	fid->uid = v9ses->uid;
	321	else
	322	fid->uid = ~0;
	323
60e78d2c AK	324	#ifdef CONFIG_9P_FSCACHE
	325	/* register the session for caching */
	326	v9fs_cache_session_get_cookie(v9ses);
	327	#endif
	328
bd238fb4	329	return fid;
9e82cf6a	330
bd238fb4	331	error:
0ed07ddb	332	bdi_destroy(&v9ses->bdi);
bd238fb4	333	return ERR_PTR(retval);
9e82cf6a EVH	334	}
	335
	336	/**
	337	* v9fs_session_close - shutdown a session
	338	* @v9ses: session information structure
	339	*
	340	*/
	341
	342	void v9fs_session_close(struct v9fs_session_info *v9ses)
	343	{
bd238fb4 LI	344	if (v9ses->clnt) {
	345	p9_client_destroy(v9ses->clnt);
	346	v9ses->clnt = NULL;
3cf6429a	347	}
9e82cf6a	348
60e78d2c AK	349	#ifdef CONFIG_9P_FSCACHE
	350	if (v9ses->fscache) {
	351	v9fs_cache_session_put_cookie(v9ses);
	352	kfree(v9ses->cachetag);
	353	}
	354	#endif
ba17674f LI	355	__putname(v9ses->uname);
ba17674f LI	356	__putname(v9ses->aname);
60e78d2c	357
0ed07ddb JA	358	bdi_destroy(&v9ses->bdi);
0ed07ddb JA	359
60e78d2c AK	360	spin_lock(&v9fs_sessionlist_lock);
	361	list_del(&v9ses->slist);
	362	spin_unlock(&v9fs_sessionlist_lock);
9e82cf6a EVH	363	}
9e82cf6a EVH	364
322b329a	365	/**
ee443996 EVH	366	* v9fs_session_cancel - terminate a session
	367	* @v9ses: session to terminate
	368	*
	369	* mark transport as disconnected and cancel all pending requests.
322b329a	370	*/
ee443996	371
322b329a	372	void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
bd238fb4 LI	373	P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
bd238fb4 LI	374	p9_client_disconnect(v9ses->clnt);
322b329a EVH	375	}
322b329a EVH	376
6d96d3ab AK	377	/**
	378	* v9fs_session_begin_cancel - Begin terminate of a session
	379	* @v9ses: session to terminate
	380	*
	381	* After this call we don't allow any request other than clunk.
	382	*/
	383
	384	void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
	385	{
	386	P9_DPRINTK(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
	387	p9_client_begin_disconnect(v9ses->clnt);
	388	}
	389
9e82cf6a EVH	390	extern int v9fs_error_init(void);
9e82cf6a EVH	391
60e78d2c AK	392	static struct kobject *v9fs_kobj;
	393
	394	#ifdef CONFIG_9P_FSCACHE
9e82cf6a	395	/**
60e78d2c AK	396	* caches_show - list caches associated with a session
	397	*
	398	* Returns the size of buffer written.
	399	*/
	400
	401	static ssize_t caches_show(struct kobject *kobj,
	402	struct kobj_attribute *attr,
	403	char *buf)
	404	{
	405	ssize_t n = 0, count = 0, limit = PAGE_SIZE;
	406	struct v9fs_session_info *v9ses;
	407
	408	spin_lock(&v9fs_sessionlist_lock);
	409	list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
	410	if (v9ses->cachetag) {
	411	n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
	412	if (n < 0) {
	413	count = n;
	414	break;
	415	}
	416
	417	count += n;
	418	limit -= n;
	419	}
	420	}
	421
	422	spin_unlock(&v9fs_sessionlist_lock);
	423	return count;
	424	}
	425
	426	static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
	427	#endif /* CONFIG_9P_FSCACHE */
	428
	429	static struct attribute *v9fs_attrs[] = {
	430	#ifdef CONFIG_9P_FSCACHE
	431	&v9fs_attr_cache.attr,
	432	#endif
	433	NULL,
	434	};
	435
	436	static struct attribute_group v9fs_attr_group = {
	437	.attrs = v9fs_attrs,
	438	};
	439
	440	/**
	441	* v9fs_sysfs_init - Initialize the v9fs sysfs interface
	442	*
	443	*/
	444
	445	static int v9fs_sysfs_init(void)
	446	{
	447	v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
	448	if (!v9fs_kobj)
	449	return -ENOMEM;
	450
	451	if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
	452	kobject_put(v9fs_kobj);
	453	return -ENOMEM;
	454	}
	455
	456	return 0;
	457	}
	458
	459	/**
460	* v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
461	*
462	*/
463
464	static void v9fs_sysfs_cleanup(void)
465	{
466	sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
467	kobject_put(v9fs_kobj);
468	}
469
470	/**
471	* init_v9fs - Initialize module
9e82cf6a EVH	472	*
	473	*/
	474
	475	static int __init init_v9fs(void)
	476	{
60e78d2c	477	int err;
f94b3470	478	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
a80d923e	479	/* TODO: Setup list of registered trasnport modules */
60e78d2c AK	480	err = register_filesystem(&v9fs_fs_type);
	481	if (err < 0) {
	482	printk(KERN_ERR "Failed to register filesystem\n");
	483	return err;
	484	}
	485
	486	err = v9fs_cache_register();
	487	if (err < 0) {
	488	printk(KERN_ERR "Failed to register v9fs for caching\n");
	489	goto out_fs_unreg;
	490	}
	491
	492	err = v9fs_sysfs_init();
	493	if (err < 0) {
	494	printk(KERN_ERR "Failed to register with sysfs\n");
	495	goto out_sysfs_cleanup;
	496	}
	497
	498	return 0;
	499
	500	out_sysfs_cleanup:
	501	v9fs_sysfs_cleanup();
	502
	503	out_fs_unreg:
	504	unregister_filesystem(&v9fs_fs_type);
	505
	506	return err;
9e82cf6a EVH	507	}
	508
	509	/**
60e78d2c	510	* exit_v9fs - shutdown module
9e82cf6a EVH	511	*
	512	*/
	513
	514	static void __exit exit_v9fs(void)
	515	{
60e78d2c AK	516	v9fs_sysfs_cleanup();
60e78d2c AK	517	v9fs_cache_unregister();
9e82cf6a EVH	518	unregister_filesystem(&v9fs_fs_type);
	519	}
	520
	521	module_init(init_v9fs)
	522	module_exit(exit_v9fs)
	523
bd238fb4	524	MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
9e82cf6a EVH	525	MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
	526	MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
	527	MODULE_LICENSE("GPL");