[net-next-2.6.git] / fs / afs / super.c

/* AFS superblock handling
 *
 * Copyright (c) 2002, 2007 Red Hat, Inc. All rights reserved.
 *
 * This software may be freely redistributed under the terms of the
 * GNU General Public License.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Authors: David Howells <dhowells@redhat.com>
 *          David Woodhouse <dwmw2@redhat.com>
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/parser.h>
#include "internal.h"

#define AFS_FS_MAGIC 0x6B414653 /* 'kAFS' */

static void afs_i_init_once(void *foo, struct kmem_cache *cachep,
			    unsigned long flags);

static int afs_get_sb(struct file_system_type *fs_type,
		      int flags, const char *dev_name,
		      void *data, struct vfsmount *mnt);

static struct inode *afs_alloc_inode(struct super_block *sb);

static void afs_put_super(struct super_block *sb);

static void afs_destroy_inode(struct inode *inode);

struct file_system_type afs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "afs",
	.get_sb		= afs_get_sb,
	.kill_sb	= kill_anon_super,
	.fs_flags	= 0,
};

static const struct super_operations afs_super_ops = {
	.statfs		= simple_statfs,
	.alloc_inode	= afs_alloc_inode,
	.drop_inode	= generic_delete_inode,
	.write_inode	= afs_write_inode,
	.destroy_inode	= afs_destroy_inode,
	.clear_inode	= afs_clear_inode,
	.umount_begin	= afs_umount_begin,
	.put_super	= afs_put_super,
};

static struct kmem_cache *afs_inode_cachep;
static atomic_t afs_count_active_inodes;

enum {
	afs_no_opt,
	afs_opt_cell,
	afs_opt_rwpath,
	afs_opt_vol,
};

static match_table_t afs_options_list = {
	{ afs_opt_cell,		"cell=%s"	},
	{ afs_opt_rwpath,	"rwpath"	},
	{ afs_opt_vol,		"vol=%s"	},
	{ afs_no_opt,		NULL		},
};

/*
 * initialise the filesystem
 */
int __init afs_fs_init(void)
{
	int ret;

	_enter("");

	/* create ourselves an inode cache */
	atomic_set(&afs_count_active_inodes, 0);

	ret = -ENOMEM;
	afs_inode_cachep = kmem_cache_create("afs_inode_cache",
					     sizeof(struct afs_vnode),
					     0,
					     SLAB_HWCACHE_ALIGN,
					     afs_i_init_once,
					     NULL);
	if (!afs_inode_cachep) {
		printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n");
		return ret;
	}

	/* now export our filesystem to lesser mortals */
	ret = register_filesystem(&afs_fs_type);
	if (ret < 0) {
		kmem_cache_destroy(afs_inode_cachep);
		_leave(" = %d", ret);
		return ret;
	}

	_leave(" = 0");
	return 0;
}

/*
 * clean up the filesystem
 */
void __exit afs_fs_exit(void)
{
	_enter("");

	afs_mntpt_kill_timer();
	unregister_filesystem(&afs_fs_type);

	if (atomic_read(&afs_count_active_inodes) != 0) {
		printk("kAFS: %d active inode objects still present\n",
		       atomic_read(&afs_count_active_inodes));
		BUG();
	}

	kmem_cache_destroy(afs_inode_cachep);
	_leave("");
}

/*
 * parse the mount options
 * - this function has been shamelessly adapted from the ext3 fs which
 *   shamelessly adapted it from the msdos fs
 */
static int afs_parse_options(struct afs_mount_params *params,
			     char *options, const char **devname)
{
	struct afs_cell *cell;
	substring_t args[MAX_OPT_ARGS];
	char *p;
	int token;

	_enter("%s", options);

	options[PAGE_SIZE - 1] = 0;

	while ((p = strsep(&options, ","))) {
		if (!*p)
			continue;

		token = match_token(p, afs_options_list, args);
		switch (token) {
		case afs_opt_cell:
			cell = afs_cell_lookup(args[0].from,
					       args[0].to - args[0].from);
			if (IS_ERR(cell))
				return PTR_ERR(cell);
			afs_put_cell(params->cell);
			params->cell = cell;
			break;

		case afs_opt_rwpath:
			params->rwpath = 1;
			break;

		case afs_opt_vol:
			*devname = args[0].from;
			break;

		default:
			printk(KERN_ERR "kAFS:"
			       " Unknown or invalid mount option: '%s'\n", p);
			return -EINVAL;
		}
	}

	_leave(" = 0");
	return 0;
}

/*
 * parse a device name to get cell name, volume name, volume type and R/W
 * selector
 * - this can be one of the following:
 *	"%[cell:]volume[.]"		R/W volume
 *	"#[cell:]volume[.]"		R/O or R/W volume (rwpath=0),
 *					 or R/W (rwpath=1) volume
 *	"%[cell:]volume.readonly"	R/O volume
 *	"#[cell:]volume.readonly"	R/O volume
 *	"%[cell:]volume.backup"		Backup volume
 *	"#[cell:]volume.backup"		Backup volume
 */
static int afs_parse_device_name(struct afs_mount_params *params,
				 const char *name)
{
	struct afs_cell *cell;
	const char *cellname, *suffix;
	int cellnamesz;

	_enter(",%s", name);

	if (!name) {
		printk(KERN_ERR "kAFS: no volume name specified\n");
		return -EINVAL;
	}

	if ((name[0] != '%' && name[0] != '#') || !name[1]) {
		printk(KERN_ERR "kAFS: unparsable volume name\n");
		return -EINVAL;
	}

	/* determine the type of volume we're looking for */
	params->type = AFSVL_ROVOL;
	params->force = false;
	if (params->rwpath || name[0] == '%') {
		params->type = AFSVL_RWVOL;
		params->force = true;
	}
	name++;

	/* split the cell name out if there is one */
	params->volname = strchr(name, ':');
	if (params->volname) {
		cellname = name;
		cellnamesz = params->volname - name;
		params->volname++;
	} else {
		params->volname = name;
		cellname = NULL;
		cellnamesz = 0;
	}

	/* the volume type is further affected by a possible suffix */
	suffix = strrchr(params->volname, '.');
	if (suffix) {
		if (strcmp(suffix, ".readonly") == 0) {
			params->type = AFSVL_ROVOL;
			params->force = true;
		} else if (strcmp(suffix, ".backup") == 0) {
			params->type = AFSVL_BACKVOL;
			params->force = true;
		} else if (suffix[1] == 0) {
		} else {
			suffix = NULL;
		}
	}

	params->volnamesz = suffix ?
		suffix - params->volname : strlen(params->volname);

	_debug("cell %*.*s [%p]",
	       cellnamesz, cellnamesz, cellname ?: "", params->cell);

	/* lookup the cell record */
	if (cellname || !params->cell) {
		cell = afs_cell_lookup(cellname, cellnamesz);
		if (IS_ERR(cell)) {
			printk(KERN_ERR "kAFS: unable to lookup cell '%s'\n",
			       cellname ?: "");
			return PTR_ERR(cell);
		}
		afs_put_cell(params->cell);
		params->cell = cell;
	}

	_debug("CELL:%s [%p] VOLUME:%*.*s SUFFIX:%s TYPE:%d%s",
	       params->cell->name, params->cell,
	       params->volnamesz, params->volnamesz, params->volname,
	       suffix ?: "-", params->type, params->force ? " FORCE" : "");

	return 0;
}

/*
 * check a superblock to see if it's the one we're looking for
 */
static int afs_test_super(struct super_block *sb, void *data)
{
	struct afs_mount_params *params = data;
	struct afs_super_info *as = sb->s_fs_info;

	return as->volume == params->volume;
}

/*
 * fill in the superblock
 */
static int afs_fill_super(struct super_block *sb, void *data)
{
	struct afs_mount_params *params = data;
	struct afs_super_info *as = NULL;
	struct afs_fid fid;
	struct dentry *root = NULL;
	struct inode *inode = NULL;
	int ret;

	_enter("");

	/* allocate a superblock info record */
	as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
	if (!as) {
		_leave(" = -ENOMEM");
		return -ENOMEM;
	}

	afs_get_volume(params->volume);
	as->volume = params->volume;

	/* fill in the superblock */
	sb->s_blocksize		= PAGE_CACHE_SIZE;
	sb->s_blocksize_bits	= PAGE_CACHE_SHIFT;
	sb->s_magic		= AFS_FS_MAGIC;
	sb->s_op		= &afs_super_ops;
	sb->s_fs_info		= as;

	/* allocate the root inode and dentry */
	fid.vid		= as->volume->vid;
	fid.vnode	= 1;
	fid.unique	= 1;
	inode = afs_iget(sb, params->key, &fid, NULL, NULL);
	if (IS_ERR(inode))
		goto error_inode;

	ret = -ENOMEM;
	root = d_alloc_root(inode);
	if (!root)
		goto error;

	sb->s_root = root;

	_leave(" = 0");
	return 0;

error_inode:
	ret = PTR_ERR(inode);
	inode = NULL;
error:
	iput(inode);
	afs_put_volume(as->volume);
	kfree(as);

	sb->s_fs_info = NULL;

	_leave(" = %d", ret);
	return ret;
}

/*
 * get an AFS superblock
 */
static int afs_get_sb(struct file_system_type *fs_type,
		      int flags,
		      const char *dev_name,
		      void *options,
		      struct vfsmount *mnt)
{
	struct afs_mount_params params;
	struct super_block *sb;
	struct afs_volume *vol;
	struct key *key;
	int ret;

	_enter(",,%s,%p", dev_name, options);

	memset(&params, 0, sizeof(params));

	/* parse the options and device name */
	if (options) {
		ret = afs_parse_options(&params, options, &dev_name);
		if (ret < 0)
			goto error;
	}

	ret = afs_parse_device_name(&params, dev_name);
	if (ret < 0)
		goto error;

	/* try and do the mount securely */
	key = afs_request_key(params.cell);
	if (IS_ERR(key)) {
		_leave(" = %ld [key]", PTR_ERR(key));
		ret = PTR_ERR(key);
		goto error;
	}
	params.key = key;

	/* parse the device name */
	vol = afs_volume_lookup(&params);
	if (IS_ERR(vol)) {
		ret = PTR_ERR(vol);
		goto error;
	}
	params.volume = vol;

	/* allocate a deviceless superblock */
	sb = sget(fs_type, afs_test_super, set_anon_super, &params);
	if (IS_ERR(sb)) {
		ret = PTR_ERR(sb);
		goto error;
	}

	if (!sb->s_root) {
		/* initial superblock/root creation */
		_debug("create");
		sb->s_flags = flags;
		ret = afs_fill_super(sb, &params);
		if (ret < 0) {
			up_write(&sb->s_umount);
			deactivate_super(sb);
			goto error;
		}
		sb->s_flags |= MS_ACTIVE;
	} else {
		_debug("reuse");
		ASSERTCMP(sb->s_flags, &, MS_ACTIVE);
	}

	simple_set_mnt(mnt, sb);
	afs_put_volume(params.volume);
	afs_put_cell(params.cell);
	_leave(" = 0 [%p]", sb);
	return 0;

error:
	afs_put_volume(params.volume);
	afs_put_cell(params.cell);
	key_put(params.key);
	_leave(" = %d", ret);
	return ret;
}

/*
 * finish the unmounting process on the superblock
 */
static void afs_put_super(struct super_block *sb)
{
	struct afs_super_info *as = sb->s_fs_info;

	_enter("");

	afs_put_volume(as->volume);

	_leave("");
}

/*
 * initialise an inode cache slab element prior to any use
 */
static void afs_i_init_once(void *_vnode, struct kmem_cache *cachep,
			    unsigned long flags)
{
	struct afs_vnode *vnode = _vnode;

	if (flags & SLAB_CTOR_CONSTRUCTOR) {
		memset(vnode, 0, sizeof(*vnode));
		inode_init_once(&vnode->vfs_inode);
		init_waitqueue_head(&vnode->update_waitq);
		mutex_init(&vnode->permits_lock);
		mutex_init(&vnode->validate_lock);
		spin_lock_init(&vnode->writeback_lock);
		spin_lock_init(&vnode->lock);
		INIT_LIST_HEAD(&vnode->writebacks);
		INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
	}
}

/*
 * allocate an AFS inode struct from our slab cache
 */
static struct inode *afs_alloc_inode(struct super_block *sb)
{
	struct afs_vnode *vnode;

	vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
	if (!vnode)
		return NULL;

	atomic_inc(&afs_count_active_inodes);

	memset(&vnode->fid, 0, sizeof(vnode->fid));
	memset(&vnode->status, 0, sizeof(vnode->status));

	vnode->volume		= NULL;
	vnode->update_cnt	= 0;
	vnode->flags		= 1 << AFS_VNODE_UNSET;
	vnode->cb_promised	= false;

	return &vnode->vfs_inode;
}

/*
 * destroy an AFS inode struct
 */
static void afs_destroy_inode(struct inode *inode)
{
	struct afs_vnode *vnode = AFS_FS_I(inode);

	_enter("{%lu}", inode->i_ino);

	_debug("DESTROY INODE %p", inode);

	ASSERTCMP(vnode->server, ==, NULL);

	kmem_cache_free(afs_inode_cachep, vnode);
	atomic_dec(&afs_count_active_inodes);
}
Commit	Line	Data
ec26815a DH	1	/* AFS superblock handling
ec26815a DH	2	*
08e0e7c8	3	* Copyright (c) 2002, 2007 Red Hat, Inc. All rights reserved.
1da177e4 LT	4	*
	5	* This software may be freely redistributed under the terms of the
	6	* GNU General Public License.
	7	*
	8	* You should have received a copy of the GNU General Public License
	9	* along with this program; if not, write to the Free Software
	10	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	11	*
	12	* Authors: David Howells <dhowells@redhat.com>
ec26815a	13	* David Woodhouse <dwmw2@redhat.com>
1da177e4 LT	14	*
	15	*/
	16
	17	#include <linux/kernel.h>
	18	#include <linux/module.h>
	19	#include <linux/init.h>
	20	#include <linux/slab.h>
	21	#include <linux/fs.h>
	22	#include <linux/pagemap.h>
80c72fe4	23	#include <linux/parser.h>
1da177e4 LT	24	#include "internal.h"
	25
	26	#define AFS_FS_MAGIC 0x6B414653 /* 'kAFS' */
	27
e18b890b	28	static void afs_i_init_once(void foo, struct kmem_cache cachep,
1da177e4 LT	29	unsigned long flags);
1da177e4 LT	30
454e2398 DH	31	static int afs_get_sb(struct file_system_type *fs_type,
	32	int flags, const char *dev_name,
	33	void data, struct vfsmount mnt);
1da177e4 LT	34
	35	static struct inode afs_alloc_inode(struct super_block sb);
	36
	37	static void afs_put_super(struct super_block *sb);
	38
	39	static void afs_destroy_inode(struct inode *inode);
	40
1f5ce9e9	41	struct file_system_type afs_fs_type = {
1da177e4 LT	42	.owner = THIS_MODULE,
	43	.name = "afs",
	44	.get_sb = afs_get_sb,
	45	.kill_sb = kill_anon_super,
80c72fe4	46	.fs_flags = 0,
1da177e4 LT	47	};
1da177e4 LT	48
ee9b6d61	49	static const struct super_operations afs_super_ops = {
1da177e4 LT	50	.statfs = simple_statfs,
	51	.alloc_inode = afs_alloc_inode,
	52	.drop_inode = generic_delete_inode,
31143d5d	53	.write_inode = afs_write_inode,
1da177e4 LT	54	.destroy_inode = afs_destroy_inode,
1da177e4 LT	55	.clear_inode = afs_clear_inode,
08e0e7c8	56	.umount_begin = afs_umount_begin,
1da177e4 LT	57	.put_super = afs_put_super,
	58	};
	59
e18b890b	60	static struct kmem_cache *afs_inode_cachep;
1da177e4 LT	61	static atomic_t afs_count_active_inodes;
1da177e4 LT	62
80c72fe4 DH	63	enum {
	64	afs_no_opt,
	65	afs_opt_cell,
	66	afs_opt_rwpath,
	67	afs_opt_vol,
	68	};
	69
31143d5d	70	static match_table_t afs_options_list = {
80c72fe4 DH	71	{ afs_opt_cell, "cell=%s" },
	72	{ afs_opt_rwpath, "rwpath" },
	73	{ afs_opt_vol, "vol=%s" },
	74	{ afs_no_opt, NULL },
	75	};
	76
1da177e4 LT	77	/*
	78	* initialise the filesystem
	79	*/
	80	int __init afs_fs_init(void)
	81	{
	82	int ret;
	83
	84	_enter("");
	85
1da177e4 LT	86	/* create ourselves an inode cache */
	87	atomic_set(&afs_count_active_inodes, 0);
	88
	89	ret = -ENOMEM;
	90	afs_inode_cachep = kmem_cache_create("afs_inode_cache",
	91	sizeof(struct afs_vnode),
	92	0,
	93	SLAB_HWCACHE_ALIGN,
	94	afs_i_init_once,
	95	NULL);
	96	if (!afs_inode_cachep) {
	97	printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n");
	98	return ret;
	99	}
	100
	101	/* now export our filesystem to lesser mortals */
	102	ret = register_filesystem(&afs_fs_type);
	103	if (ret < 0) {
	104	kmem_cache_destroy(afs_inode_cachep);
08e0e7c8	105	_leave(" = %d", ret);
1da177e4 LT	106	return ret;
	107	}
	108
08e0e7c8	109	_leave(" = 0");
1da177e4	110	return 0;
ec26815a	111	}
1da177e4	112
1da177e4 LT	113	/*
	114	* clean up the filesystem
	115	*/
	116	void __exit afs_fs_exit(void)
	117	{
08e0e7c8 DH	118	_enter("");
	119
	120	afs_mntpt_kill_timer();
1da177e4 LT	121	unregister_filesystem(&afs_fs_type);
	122
	123	if (atomic_read(&afs_count_active_inodes) != 0) {
	124	printk("kAFS: %d active inode objects still present\n",
	125	atomic_read(&afs_count_active_inodes));
	126	BUG();
	127	}
	128
	129	kmem_cache_destroy(afs_inode_cachep);
08e0e7c8	130	_leave("");
ec26815a	131	}
1da177e4	132
1da177e4 LT	133	/*
	134	* parse the mount options
	135	* - this function has been shamelessly adapted from the ext3 fs which
	136	* shamelessly adapted it from the msdos fs
	137	*/
00d3b7a4 DH	138	static int afs_parse_options(struct afs_mount_params *params,
00d3b7a4 DH	139	char options, const char *devname)
1da177e4	140	{
08e0e7c8	141	struct afs_cell *cell;
80c72fe4 DH	142	substring_t args[MAX_OPT_ARGS];
	143	char *p;
	144	int token;
1da177e4 LT	145
	146	_enter("%s", options);
	147
	148	options[PAGE_SIZE - 1] = 0;
	149
80c72fe4 DH	150	while ((p = strsep(&options, ","))) {
	151	if (!*p)
	152	continue;
1da177e4	153
80c72fe4 DH	154	token = match_token(p, afs_options_list, args);
	155	switch (token) {
	156	case afs_opt_cell:
	157	cell = afs_cell_lookup(args[0].from,
	158	args[0].to - args[0].from);
08e0e7c8 DH	159	if (IS_ERR(cell))
08e0e7c8 DH	160	return PTR_ERR(cell);
00d3b7a4 DH	161	afs_put_cell(params->cell);
00d3b7a4 DH	162	params->cell = cell;
80c72fe4 DH	163	break;
	164
	165	case afs_opt_rwpath:
	166	params->rwpath = 1;
	167	break;
	168
	169	case afs_opt_vol:
	170	*devname = args[0].from;
	171	break;
	172
	173	default:
	174	printk(KERN_ERR "kAFS:"
	175	" Unknown or invalid mount option: '%s'\n", p);
	176	return -EINVAL;
1da177e4	177	}
1da177e4 LT	178	}
1da177e4 LT	179
80c72fe4 DH	180	_leave(" = 0");
80c72fe4 DH	181	return 0;
ec26815a	182	}
1da177e4	183
00d3b7a4 DH	184	/*
	185	* parse a device name to get cell name, volume name, volume type and R/W
	186	* selector
	187	* - this can be one of the following:
	188	* "%[cell:]volume[.]" R/W volume
	189	* "#[cell:]volume[.]" R/O or R/W volume (rwpath=0),
	190	* or R/W (rwpath=1) volume
	191	* "%[cell:]volume.readonly" R/O volume
	192	* "#[cell:]volume.readonly" R/O volume
	193	* "%[cell:]volume.backup" Backup volume
	194	* "#[cell:]volume.backup" Backup volume
	195	*/
	196	static int afs_parse_device_name(struct afs_mount_params *params,
	197	const char *name)
	198	{
	199	struct afs_cell *cell;
	200	const char cellname, suffix;
	201	int cellnamesz;
	202
	203	_enter(",%s", name);
	204
	205	if (!name) {
	206	printk(KERN_ERR "kAFS: no volume name specified\n");
	207	return -EINVAL;
	208	}
	209
	210	if ((name[0] != '%' && name[0] != '#') \|\| !name[1]) {
	211	printk(KERN_ERR "kAFS: unparsable volume name\n");
	212	return -EINVAL;
	213	}
	214
	215	/* determine the type of volume we're looking for */
	216	params->type = AFSVL_ROVOL;
	217	params->force = false;
	218	if (params->rwpath \|\| name[0] == '%') {
	219	params->type = AFSVL_RWVOL;
	220	params->force = true;
	221	}
	222	name++;
	223
	224	/* split the cell name out if there is one */
	225	params->volname = strchr(name, ':');
	226	if (params->volname) {
	227	cellname = name;
	228	cellnamesz = params->volname - name;
	229	params->volname++;
	230	} else {
	231	params->volname = name;
	232	cellname = NULL;
	233	cellnamesz = 0;
	234	}
	235
	236	/* the volume type is further affected by a possible suffix */
	237	suffix = strrchr(params->volname, '.');
	238	if (suffix) {
	239	if (strcmp(suffix, ".readonly") == 0) {
	240	params->type = AFSVL_ROVOL;
	241	params->force = true;
	242	} else if (strcmp(suffix, ".backup") == 0) {
	243	params->type = AFSVL_BACKVOL;
	244	params->force = true;
	245	} else if (suffix[1] == 0) {
	246	} else {
	247	suffix = NULL;
248	}
249	}
250
251	params->volnamesz = suffix ?
252	suffix - params->volname : strlen(params->volname);
253
254	_debug("cell %.s [%p]",
255	cellnamesz, cellnamesz, cellname ?: "", params->cell);
256
257	/* lookup the cell record */
258	if (cellname \|\| !params->cell) {
259	cell = afs_cell_lookup(cellname, cellnamesz);
260	if (IS_ERR(cell)) {
261	printk(KERN_ERR "kAFS: unable to lookup cell '%s'\n",
262	cellname ?: "");
263	return PTR_ERR(cell);
264	}
265	afs_put_cell(params->cell);
266	params->cell = cell;
267	}
268
269	_debug("CELL:%s [%p] VOLUME:%.s SUFFIX:%s TYPE:%d%s",
270	params->cell->name, params->cell,
271	params->volnamesz, params->volnamesz, params->volname,
272	suffix ?: "-", params->type, params->force ? " FORCE" : "");
273
274	return 0;
275	}
276
1da177e4 LT	277	/*
	278	* check a superblock to see if it's the one we're looking for
	279	*/
	280	static int afs_test_super(struct super_block sb, void data)
	281	{
	282	struct afs_mount_params *params = data;
	283	struct afs_super_info *as = sb->s_fs_info;
	284
	285	return as->volume == params->volume;
ec26815a	286	}
1da177e4	287
1da177e4 LT	288	/*
	289	* fill in the superblock
	290	*/
436058a4	291	static int afs_fill_super(struct super_block sb, void data)
1da177e4 LT	292	{
	293	struct afs_mount_params *params = data;
	294	struct afs_super_info *as = NULL;
	295	struct afs_fid fid;
	296	struct dentry *root = NULL;
	297	struct inode *inode = NULL;
	298	int ret;
	299
08e0e7c8	300	_enter("");
1da177e4 LT	301
1da177e4 LT	302	/* allocate a superblock info record */
b593e48d	303	as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
1da177e4 LT	304	if (!as) {
	305	_leave(" = -ENOMEM");
	306	return -ENOMEM;
	307	}
	308
1da177e4 LT	309	afs_get_volume(params->volume);
	310	as->volume = params->volume;
	311
	312	/* fill in the superblock */
	313	sb->s_blocksize = PAGE_CACHE_SIZE;
	314	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	315	sb->s_magic = AFS_FS_MAGIC;
	316	sb->s_op = &afs_super_ops;
	317	sb->s_fs_info = as;
	318
	319	/* allocate the root inode and dentry */
	320	fid.vid = as->volume->vid;
	321	fid.vnode = 1;
	322	fid.unique = 1;
260a9803	323	inode = afs_iget(sb, params->key, &fid, NULL, NULL);
08e0e7c8 DH	324	if (IS_ERR(inode))
08e0e7c8 DH	325	goto error_inode;
1da177e4 LT	326
	327	ret = -ENOMEM;
	328	root = d_alloc_root(inode);
	329	if (!root)
	330	goto error;
	331
	332	sb->s_root = root;
	333
08e0e7c8	334	_leave(" = 0");
1da177e4 LT	335	return 0;
1da177e4 LT	336
08e0e7c8 DH	337	error_inode:
	338	ret = PTR_ERR(inode);
	339	inode = NULL;
ec26815a	340	error:
1da177e4 LT	341	iput(inode);
	342	afs_put_volume(as->volume);
	343	kfree(as);
	344
	345	sb->s_fs_info = NULL;
	346
08e0e7c8	347	_leave(" = %d", ret);
1da177e4	348	return ret;
ec26815a	349	}
1da177e4	350
1da177e4 LT	351	/*
1da177e4 LT	352	* get an AFS superblock
1da177e4	353	*/
454e2398 DH	354	static int afs_get_sb(struct file_system_type *fs_type,
	355	int flags,
	356	const char *dev_name,
	357	void *options,
	358	struct vfsmount *mnt)
1da177e4 LT	359	{
	360	struct afs_mount_params params;
	361	struct super_block *sb;
08e0e7c8	362	struct afs_volume *vol;
00d3b7a4	363	struct key *key;
1da177e4 LT	364	int ret;
	365
	366	_enter(",,%s,%p", dev_name, options);
	367
	368	memset(&params, 0, sizeof(params));
	369
00d3b7a4	370	/* parse the options and device name */
1da177e4	371	if (options) {
00d3b7a4	372	ret = afs_parse_options(&params, options, &dev_name);
1da177e4 LT	373	if (ret < 0)
1da177e4 LT	374	goto error;
1da177e4 LT	375	}
1da177e4 LT	376
00d3b7a4 DH	377	ret = afs_parse_device_name(&params, dev_name);
	378	if (ret < 0)
	379	goto error;
	380
	381	/* try and do the mount securely */
	382	key = afs_request_key(params.cell);
	383	if (IS_ERR(key)) {
	384	_leave(" = %ld [key]", PTR_ERR(key));
	385	ret = PTR_ERR(key);
	386	goto error;
	387	}
	388	params.key = key;
	389
1da177e4	390	/* parse the device name */
00d3b7a4	391	vol = afs_volume_lookup(&params);
08e0e7c8 DH	392	if (IS_ERR(vol)) {
08e0e7c8 DH	393	ret = PTR_ERR(vol);
1da177e4	394	goto error;
08e0e7c8	395	}
08e0e7c8	396	params.volume = vol;
1da177e4 LT	397
	398	/* allocate a deviceless superblock */
	399	sb = sget(fs_type, afs_test_super, set_anon_super, &params);
08e0e7c8 DH	400	if (IS_ERR(sb)) {
08e0e7c8 DH	401	ret = PTR_ERR(sb);
1da177e4	402	goto error;
08e0e7c8	403	}
1da177e4	404
436058a4 DH	405	if (!sb->s_root) {
	406	/* initial superblock/root creation */
	407	_debug("create");
	408	sb->s_flags = flags;
	409	ret = afs_fill_super(sb, &params);
	410	if (ret < 0) {
	411	up_write(&sb->s_umount);
	412	deactivate_super(sb);
	413	goto error;
	414	}
	415	sb->s_flags \|= MS_ACTIVE;
	416	} else {
	417	_debug("reuse");
	418	ASSERTCMP(sb->s_flags, &, MS_ACTIVE);
1da177e4	419	}
1da177e4	420
436058a4	421	simple_set_mnt(mnt, sb);
1da177e4	422	afs_put_volume(params.volume);
00d3b7a4	423	afs_put_cell(params.cell);
08e0e7c8	424	_leave(" = 0 [%p]", sb);
454e2398	425	return 0;
1da177e4	426
ec26815a	427	error:
1da177e4	428	afs_put_volume(params.volume);
00d3b7a4 DH	429	afs_put_cell(params.cell);
00d3b7a4 DH	430	key_put(params.key);
1da177e4	431	_leave(" = %d", ret);
454e2398	432	return ret;
ec26815a	433	}
1da177e4	434
1da177e4 LT	435	/*
	436	* finish the unmounting process on the superblock
	437	*/
	438	static void afs_put_super(struct super_block *sb)
	439	{
	440	struct afs_super_info *as = sb->s_fs_info;
	441
	442	_enter("");
	443
	444	afs_put_volume(as->volume);
1da177e4 LT	445
1da177e4 LT	446	_leave("");
ec26815a	447	}
1da177e4	448
1da177e4 LT	449	/*
	450	* initialise an inode cache slab element prior to any use
	451	*/
e18b890b	452	static void afs_i_init_once(void _vnode, struct kmem_cache cachep,
1da177e4 LT	453	unsigned long flags)
1da177e4 LT	454	{
ec26815a	455	struct afs_vnode *vnode = _vnode;
1da177e4	456
50953fe9	457	if (flags & SLAB_CTOR_CONSTRUCTOR) {
1da177e4 LT	458	memset(vnode, 0, sizeof(*vnode));
	459	inode_init_once(&vnode->vfs_inode);
	460	init_waitqueue_head(&vnode->update_waitq);
00d3b7a4	461	mutex_init(&vnode->permits_lock);
260a9803	462	mutex_init(&vnode->validate_lock);
31143d5d	463	spin_lock_init(&vnode->writeback_lock);
1da177e4	464	spin_lock_init(&vnode->lock);
31143d5d	465	INIT_LIST_HEAD(&vnode->writebacks);
08e0e7c8	466	INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
1da177e4	467	}
ec26815a	468	}
1da177e4	469
1da177e4 LT	470	/*
	471	* allocate an AFS inode struct from our slab cache
	472	*/
	473	static struct inode afs_alloc_inode(struct super_block sb)
	474	{
	475	struct afs_vnode *vnode;
	476
ec26815a	477	vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
1da177e4 LT	478	if (!vnode)
	479	return NULL;
	480
	481	atomic_inc(&afs_count_active_inodes);
	482
	483	memset(&vnode->fid, 0, sizeof(vnode->fid));
	484	memset(&vnode->status, 0, sizeof(vnode->status));
	485
	486	vnode->volume = NULL;
	487	vnode->update_cnt = 0;
260a9803	488	vnode->flags = 1 << AFS_VNODE_UNSET;
08e0e7c8	489	vnode->cb_promised = false;
1da177e4 LT	490
1da177e4 LT	491	return &vnode->vfs_inode;
ec26815a	492	}
1da177e4	493
1da177e4 LT	494	/*
	495	* destroy an AFS inode struct
	496	*/
	497	static void afs_destroy_inode(struct inode *inode)
	498	{
08e0e7c8 DH	499	struct afs_vnode *vnode = AFS_FS_I(inode);
08e0e7c8 DH	500
1da177e4 LT	501	_enter("{%lu}", inode->i_ino);
1da177e4 LT	502
08e0e7c8 DH	503	_debug("DESTROY INODE %p", inode);
	504
	505	ASSERTCMP(vnode->server, ==, NULL);
	506
	507	kmem_cache_free(afs_inode_cachep, vnode);
1da177e4	508	atomic_dec(&afs_count_active_inodes);
ec26815a	509	}