[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 <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, Opt_posixacl,
	/* 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_posixacl, "posixacl"},
	{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) {
				v9ses->flags |= V9FS_ACCESS_CLIENT;
			} else {
				v9ses->flags |= V9FS_ACCESS_SINGLE;
				v9ses->uid = simple_strtoul(s, &e, 10);
				if (*e != '\0')
					v9ses->uid = ~0;
			}
			kfree(s);
			break;

		case Opt_posixacl:
#ifdef CONFIG_9P_FS_POSIX_ACL
			v9ses->flags |= V9FS_POSIX_ACL;
#else
			P9_DPRINTK(P9_DEBUG_ERROR,
					"Not defined CONFIG_9P_FS_POSIX_ACL. "
					"Ignoring posixacl option\n");
#endif
			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);

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

	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;
	}

	v9ses->flags = V9FS_ACCESS_USER;

	if (p9_is_proto_dotl(v9ses->clnt)) {
		v9ses->flags = V9FS_ACCESS_CLIENT;
		v9ses->flags |= V9FS_PROTO_2000L;
	} else if (p9_is_proto_dotu(v9ses->clnt)) {
		v9ses->flags |= V9FS_PROTO_2000U;
	}

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

	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;
	}
	if (!v9fs_proto_dotl(v9ses) ||
		!((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
		/*
		 * We support ACL checks on clinet only if the protocol is
		 * 9P2000.L and access is V9FS_ACCESS_CLIENT.
		 */
		v9ses->flags &= ~V9FS_ACL_MASK;
	}

	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	57	/* Access options */
e782ef71	58	Opt_access, Opt_posixacl,
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"},
e782ef71	76	{Opt_posixacl, "posixacl"},
9e82cf6a EVH	77	{Opt_err, NULL}
	78	};
	79
9e82cf6a EVH	80	/**
9e82cf6a EVH	81	* v9fs_parse_options - parse mount options into session structure
9e82cf6a EVH	82	* @v9ses: existing v9fs session information
9e82cf6a EVH	83	*
ab31267d	84	* Return 0 upon success, -ERRNO upon failure.
9e82cf6a EVH	85	*/
9e82cf6a EVH	86
4b53e4b5	87	static int v9fs_parse_options(struct v9fs_session_info v9ses, char opts)
9e82cf6a	88	{
d8c8a9e3	89	char options, tmp_options;
9e82cf6a	90	substring_t args[MAX_OPT_ARGS];
a80d923e	91	char *p;
8a0dc95f	92	int option = 0;
ba17674f	93	char s, e;
ab31267d	94	int ret = 0;
9e82cf6a EVH	95
9e82cf6a EVH	96	/* setup defaults */
9e82cf6a EVH	97	v9ses->afid = ~0;
9e82cf6a EVH	98	v9ses->debug = 0;
e03abc0c	99	v9ses->cache = 0;
60e78d2c AK	100	#ifdef CONFIG_9P_FSCACHE
	101	v9ses->cachetag = NULL;
	102	#endif
9e82cf6a	103
4b53e4b5	104	if (!opts)
ab31267d	105	return 0;
9e82cf6a	106
d8c8a9e3	107	tmp_options = kstrdup(opts, GFP_KERNEL);
bf2d29c6 EVH	108	if (!tmp_options) {
bf2d29c6 EVH	109	ret = -ENOMEM;
60e78d2c	110	goto fail_option_alloc;
bf2d29c6	111	}
d8c8a9e3	112	options = tmp_options;
ab31267d	113
9e82cf6a EVH	114	while ((p = strsep(&options, ",")) != NULL) {
	115	int token;
	116	if (!*p)
	117	continue;
	118	token = match_token(p, tokens, args);
67543e50	119	if (token < Opt_uname) {
ab31267d JM	120	int r = match_int(&args[0], &option);
ab31267d JM	121	if (r < 0) {
bd238fb4	122	P9_DPRINTK(P9_DEBUG_ERROR,
9e82cf6a	123	"integer field, but no integer?\n");
ab31267d	124	ret = r;
9e82cf6a EVH	125	continue;
9e82cf6a EVH	126	}
9e82cf6a EVH	127	}
9e82cf6a EVH	128	switch (token) {
9e2f6688 EVH	129	case Opt_debug:
9e2f6688 EVH	130	v9ses->debug = option;
10fa16e7	131	#ifdef CONFIG_NET_9P_DEBUG
9e2f6688	132	p9_debug_level = option;
10fa16e7	133	#endif
9e2f6688	134	break;
8a0dc95f	135
bd32b82d LI	136	case Opt_dfltuid:
bd32b82d LI	137	v9ses->dfltuid = option;
9e82cf6a	138	break;
bd32b82d LI	139	case Opt_dfltgid:
bd32b82d LI	140	v9ses->dfltgid = option;
9e82cf6a EVH	141	break;
	142	case Opt_afid:
	143	v9ses->afid = option;
	144	break;
67543e50	145	case Opt_uname:
b32a09db	146	match_strlcpy(v9ses->uname, &args[0], PATH_MAX);
9e82cf6a EVH	147	break;
9e82cf6a EVH	148	case Opt_remotename:
b32a09db	149	match_strlcpy(v9ses->aname, &args[0], PATH_MAX);
9e82cf6a	150	break;
9e82cf6a EVH	151	case Opt_nodevmap:
	152	v9ses->nodev = 1;
	153	break;
e03abc0c EVH	154	case Opt_cache_loose:
	155	v9ses->cache = CACHE_LOOSE;
	156	break;
60e78d2c AK	157	case Opt_fscache:
	158	v9ses->cache = CACHE_FSCACHE;
	159	break;
	160	case Opt_cachetag:
	161	#ifdef CONFIG_9P_FSCACHE
	162	v9ses->cachetag = match_strdup(&args[0]);
	163	#endif
	164	break;
	165	case Opt_cache:
	166	s = match_strdup(&args[0]);
bf2d29c6 EVH	167	if (!s) {
	168	ret = -ENOMEM;
	169	P9_DPRINTK(P9_DEBUG_ERROR,
	170	"problem allocating copy of cache arg\n");
	171	goto free_and_return;
	172	}
60e78d2c AK	173
	174	if (strcmp(s, "loose") == 0)
	175	v9ses->cache = CACHE_LOOSE;
	176	else if (strcmp(s, "fscache") == 0)
	177	v9ses->cache = CACHE_FSCACHE;
	178	else
	179	v9ses->cache = CACHE_NONE;
	180	kfree(s);
	181	break;
ba17674f LI	182
	183	case Opt_access:
	184	s = match_strdup(&args[0]);
bf2d29c6 EVH	185	if (!s) {
	186	ret = -ENOMEM;
	187	P9_DPRINTK(P9_DEBUG_ERROR,
	188	"problem allocating copy of access arg\n");
	189	goto free_and_return;
	190	}
60e78d2c	191
ba17674f LI	192	v9ses->flags &= ~V9FS_ACCESS_MASK;
	193	if (strcmp(s, "user") == 0)
	194	v9ses->flags \|= V9FS_ACCESS_USER;
	195	else if (strcmp(s, "any") == 0)
	196	v9ses->flags \|= V9FS_ACCESS_ANY;
76381a42	197	else if (strcmp(s, "client") == 0) {
76381a42	198	v9ses->flags \|= V9FS_ACCESS_CLIENT;
76381a42	199	} else {
ba17674f	200	v9ses->flags \|= V9FS_ACCESS_SINGLE;
f1d9e458	201	v9ses->uid = simple_strtoul(s, &e, 10);
ba17674f LI	202	if (*e != '\0')
	203	v9ses->uid = ~0;
	204	}
0a976297	205	kfree(s);
ba17674f LI	206	break;
ba17674f LI	207
e782ef71 VJJ	208	case Opt_posixacl:
	209	#ifdef CONFIG_9P_FS_POSIX_ACL
	210	v9ses->flags \|= V9FS_POSIX_ACL;
	211	#else
	212	P9_DPRINTK(P9_DEBUG_ERROR,
	213	"Not defined CONFIG_9P_FS_POSIX_ACL. "
	214	"Ignoring posixacl option\n");
	215	#endif
	216	break;
	217
9e82cf6a EVH	218	default:
	219	continue;
	220	}
	221	}
d8c8a9e3	222
bf2d29c6	223	free_and_return:
d8c8a9e3	224	kfree(tmp_options);
60e78d2c	225	fail_option_alloc:
bf2d29c6	226	return ret;
9e82cf6a EVH	227	}
9e82cf6a EVH	228
9e82cf6a EVH	229	/**
	230	* v9fs_session_init - initialize session
	231	* @v9ses: session information structure
	232	* @dev_name: device being mounted
	233	* @data: options
	234	*
	235	*/
	236
bd238fb4	237	struct p9_fid v9fs_session_init(struct v9fs_session_info v9ses,
9e82cf6a EVH	238	const char dev_name, char data)
9e82cf6a EVH	239	{
9e82cf6a	240	int retval = -EINVAL;
bd238fb4	241	struct p9_fid *fid;
ab31267d	242	int rc;
9e82cf6a	243
ba17674f LI	244	v9ses->uname = __getname();
ba17674f LI	245	if (!v9ses->uname)
bd238fb4	246	return ERR_PTR(-ENOMEM);
9e82cf6a	247
ba17674f LI	248	v9ses->aname = __getname();
	249	if (!v9ses->aname) {
	250	__putname(v9ses->uname);
bd238fb4	251	return ERR_PTR(-ENOMEM);
9e82cf6a	252	}
a534c8d1	253	init_rwsem(&v9ses->rename_sem);
9e82cf6a	254
0ed07ddb JA	255	rc = bdi_setup_and_register(&v9ses->bdi, "9p", BDI_CAP_MAP_COPY);
	256	if (rc) {
	257	__putname(v9ses->aname);
	258	__putname(v9ses->uname);
	259	return ERR_PTR(rc);
	260	}
	261
60e78d2c AK	262	spin_lock(&v9fs_sessionlist_lock);
	263	list_add(&v9ses->slist, &v9fs_sessionlist);
	264	spin_unlock(&v9fs_sessionlist_lock);
	265
ba17674f LI	266	strcpy(v9ses->uname, V9FS_DEFUSER);
	267	strcpy(v9ses->aname, V9FS_DEFANAME);
	268	v9ses->uid = ~0;
bd32b82d LI	269	v9ses->dfltuid = V9FS_DEFUID;
bd32b82d LI	270	v9ses->dfltgid = V9FS_DEFGID;
ab31267d	271
4b53e4b5	272	v9ses->clnt = p9_client_create(dev_name, data);
bd238fb4 LI	273	if (IS_ERR(v9ses->clnt)) {
	274	retval = PTR_ERR(v9ses->clnt);
	275	v9ses->clnt = NULL;
	276	P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
	277	goto error;
9e82cf6a EVH	278	}
9e82cf6a EVH	279
6752a1eb VJJ	280	v9ses->flags = V9FS_ACCESS_USER;
	281
	282	if (p9_is_proto_dotl(v9ses->clnt)) {
	283	v9ses->flags = V9FS_ACCESS_CLIENT;
476ada04	284	v9ses->flags \|= V9FS_PROTO_2000L;
6752a1eb	285	} else if (p9_is_proto_dotu(v9ses->clnt)) {
476ada04	286	v9ses->flags \|= V9FS_PROTO_2000U;
6752a1eb VJJ	287	}
	288
	289	rc = v9fs_parse_options(v9ses, data);
	290	if (rc < 0) {
	291	retval = rc;
	292	goto error;
	293	}
ba17674f	294
fbedadc1	295	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
8a0dc95f	296
76381a42 AK	297	if (!v9fs_proto_dotl(v9ses) &&
	298	((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
	299	/*
	300	* We support ACCESS_CLIENT only for dotl.
	301	* Fall back to ACCESS_USER
	302	*/
	303	v9ses->flags &= ~V9FS_ACCESS_MASK;
	304	v9ses->flags \|= V9FS_ACCESS_USER;
	305	}
	306	/FIXME !! /
ba17674f	307	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
9ffaf63e	308	if (!(v9fs_proto_dotu(v9ses) \|\| v9fs_proto_dotl(v9ses)) &&
ba17674f LI	309	((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
	310
	311	v9ses->flags &= ~V9FS_ACCESS_MASK;
	312	v9ses->flags \|= V9FS_ACCESS_ANY;
	313	v9ses->uid = ~0;
	314	}
e782ef71 VJJ	315	if (!v9fs_proto_dotl(v9ses) \|\|
	316	!((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
	317	/*
	318	* We support ACL checks on clinet only if the protocol is
	319	* 9P2000.L and access is V9FS_ACCESS_CLIENT.
	320	*/
	321	v9ses->flags &= ~V9FS_ACL_MASK;
	322	}
ba17674f LI	323
	324	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
	325	v9ses->aname);
bd238fb4 LI	326	if (IS_ERR(fid)) {
	327	retval = PTR_ERR(fid);
	328	fid = NULL;
	329	P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
	330	goto error;
9e82cf6a EVH	331	}
9e82cf6a EVH	332
ba17674f LI	333	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
	334	fid->uid = v9ses->uid;
	335	else
	336	fid->uid = ~0;
	337
60e78d2c AK	338	#ifdef CONFIG_9P_FSCACHE
	339	/* register the session for caching */
	340	v9fs_cache_session_get_cookie(v9ses);
	341	#endif
	342
bd238fb4	343	return fid;
9e82cf6a	344
bd238fb4	345	error:
0ed07ddb	346	bdi_destroy(&v9ses->bdi);
bd238fb4	347	return ERR_PTR(retval);
9e82cf6a EVH	348	}
	349
	350	/**
	351	* v9fs_session_close - shutdown a session
	352	* @v9ses: session information structure
	353	*
	354	*/
	355
	356	void v9fs_session_close(struct v9fs_session_info *v9ses)
	357	{
bd238fb4 LI	358	if (v9ses->clnt) {
	359	p9_client_destroy(v9ses->clnt);
	360	v9ses->clnt = NULL;
3cf6429a	361	}
9e82cf6a	362
60e78d2c AK	363	#ifdef CONFIG_9P_FSCACHE
	364	if (v9ses->fscache) {
	365	v9fs_cache_session_put_cookie(v9ses);
	366	kfree(v9ses->cachetag);
	367	}
	368	#endif
ba17674f LI	369	__putname(v9ses->uname);
ba17674f LI	370	__putname(v9ses->aname);
60e78d2c	371
0ed07ddb JA	372	bdi_destroy(&v9ses->bdi);
0ed07ddb JA	373
60e78d2c AK	374	spin_lock(&v9fs_sessionlist_lock);
	375	list_del(&v9ses->slist);
	376	spin_unlock(&v9fs_sessionlist_lock);
9e82cf6a EVH	377	}
9e82cf6a EVH	378
322b329a	379	/**
ee443996 EVH	380	* v9fs_session_cancel - terminate a session
	381	* @v9ses: session to terminate
	382	*
	383	* mark transport as disconnected and cancel all pending requests.
322b329a	384	*/
ee443996	385
322b329a	386	void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
bd238fb4 LI	387	P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
bd238fb4 LI	388	p9_client_disconnect(v9ses->clnt);
322b329a EVH	389	}
322b329a EVH	390
6d96d3ab AK	391	/**
	392	* v9fs_session_begin_cancel - Begin terminate of a session
	393	* @v9ses: session to terminate
	394	*
	395	* After this call we don't allow any request other than clunk.
	396	*/
	397
	398	void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
	399	{
	400	P9_DPRINTK(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
	401	p9_client_begin_disconnect(v9ses->clnt);
	402	}
	403
9e82cf6a EVH	404	extern int v9fs_error_init(void);
9e82cf6a EVH	405
60e78d2c AK	406	static struct kobject *v9fs_kobj;
	407
	408	#ifdef CONFIG_9P_FSCACHE
9e82cf6a	409	/**
60e78d2c AK	410	* caches_show - list caches associated with a session
	411	*
	412	* Returns the size of buffer written.
	413	*/
	414
	415	static ssize_t caches_show(struct kobject *kobj,
	416	struct kobj_attribute *attr,
	417	char *buf)
	418	{
	419	ssize_t n = 0, count = 0, limit = PAGE_SIZE;
	420	struct v9fs_session_info *v9ses;
	421
	422	spin_lock(&v9fs_sessionlist_lock);
	423	list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
	424	if (v9ses->cachetag) {
	425	n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
	426	if (n < 0) {
	427	count = n;
	428	break;
	429	}
	430
	431	count += n;
	432	limit -= n;
	433	}
	434	}
	435
	436	spin_unlock(&v9fs_sessionlist_lock);
	437	return count;
	438	}
	439
	440	static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
	441	#endif /* CONFIG_9P_FSCACHE */
	442
	443	static struct attribute *v9fs_attrs[] = {
	444	#ifdef CONFIG_9P_FSCACHE
	445	&v9fs_attr_cache.attr,
	446	#endif
	447	NULL,
	448	};
	449
	450	static struct attribute_group v9fs_attr_group = {
	451	.attrs = v9fs_attrs,
	452	};
	453
	454	/**
	455	* v9fs_sysfs_init - Initialize the v9fs sysfs interface
	456	*
	457	*/
	458
	459	static int v9fs_sysfs_init(void)
	460	{
	461	v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
	462	if (!v9fs_kobj)
	463	return -ENOMEM;
	464
	465	if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
	466	kobject_put(v9fs_kobj);
	467	return -ENOMEM;
	468	}
	469
	470	return 0;
	471	}
	472
	473	/**
474	* v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
475	*
476	*/
477
478	static void v9fs_sysfs_cleanup(void)
479	{
480	sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
481	kobject_put(v9fs_kobj);
482	}
483
484	/**
485	* init_v9fs - Initialize module
9e82cf6a EVH	486	*
	487	*/
	488
	489	static int __init init_v9fs(void)
	490	{
60e78d2c	491	int err;
f94b3470	492	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
a80d923e	493	/* TODO: Setup list of registered trasnport modules */
60e78d2c AK	494	err = register_filesystem(&v9fs_fs_type);
	495	if (err < 0) {
	496	printk(KERN_ERR "Failed to register filesystem\n");
	497	return err;
	498	}
	499
	500	err = v9fs_cache_register();
	501	if (err < 0) {
	502	printk(KERN_ERR "Failed to register v9fs for caching\n");
	503	goto out_fs_unreg;
	504	}
	505
	506	err = v9fs_sysfs_init();
	507	if (err < 0) {
	508	printk(KERN_ERR "Failed to register with sysfs\n");
	509	goto out_sysfs_cleanup;
	510	}
	511
	512	return 0;
	513
	514	out_sysfs_cleanup:
	515	v9fs_sysfs_cleanup();
	516
	517	out_fs_unreg:
	518	unregister_filesystem(&v9fs_fs_type);
	519
	520	return err;
9e82cf6a EVH	521	}
	522
	523	/**
60e78d2c	524	* exit_v9fs - shutdown module
9e82cf6a EVH	525	*
	526	*/
	527
	528	static void __exit exit_v9fs(void)
	529	{
60e78d2c AK	530	v9fs_sysfs_cleanup();
60e78d2c AK	531	v9fs_cache_unregister();
9e82cf6a EVH	532	unregister_filesystem(&v9fs_fs_type);
	533	}
	534
	535	module_init(init_v9fs)
	536	module_exit(exit_v9fs)
	537
bd238fb4	538	MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
9e82cf6a EVH	539	MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
	540	MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
	541	MODULE_LICENSE("GPL");