[linux-2.6-block.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 "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	= FS_BINARY_MOUNTDATA,
};

static const struct super_operations afs_super_ops = {
	.statfs		= simple_statfs,
	.alloc_inode	= afs_alloc_inode,
	.drop_inode	= generic_delete_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;

/*
 * 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("");
}

/*
 * check that an argument has a value
 */
static int want_arg(char **_value, const char *option)
{
	if (!_value || !*_value || !**_value) {
		printk(KERN_NOTICE "kAFS: %s: argument missing\n", option);
		return 0;
	}
	return 1;
}

/*
 * check that there's no subsequent value
 */
static int want_no_value(char *const *_value, const char *option)
{
	if (*_value && **_value) {
		printk(KERN_NOTICE "kAFS: %s: Invalid argument: %s\n",
		       option, *_value);
		return 0;
	}
	return 1;
}

/*
 * 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;
	char *key, *value;
	int ret;

	_enter("%s", options);

	options[PAGE_SIZE - 1] = 0;

	ret = 0;
	while ((key = strsep(&options, ","))) {
		value = strchr(key, '=');
		if (value)
			*value++ = 0;

		_debug("kAFS: KEY: %s, VAL:%s", key, value ?: "-");

		if (strcmp(key, "rwpath") == 0) {
			if (!want_no_value(&value, "rwpath"))
				return -EINVAL;
			params->rwpath = 1;
		} else if (strcmp(key, "vol") == 0) {
			if (!want_arg(&value, "vol"))
				return -EINVAL;
			*devname = value;
		} else if (strcmp(key, "cell") == 0) {
			if (!want_arg(&value, "cell"))
				return -EINVAL;
			cell = afs_cell_lookup(value, strlen(value));
			if (IS_ERR(cell))
				return PTR_ERR(cell);
			afs_put_cell(params->cell);
			params->cell = cell;
		} else {
			printk("kAFS: Unknown mount option: '%s'\n",  key);
			ret = -EINVAL;
			goto error;
		}
	}

	ret = 0;
error:
	_leave(" = %d", ret);
	return ret;
}

/*
 * 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);
	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
 * - TODO: don't use get_sb_nodev(), but rather call sget() directly
 */
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_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
	    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);
		spin_lock_init(&vnode->lock);
		INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
		mutex_init(&vnode->cb_broken_lock);
	}
}

/*
 * 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		= 0;
	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>
1da177e4 LT	23	#include "internal.h"
	24
	25	#define AFS_FS_MAGIC 0x6B414653 /* 'kAFS' */
	26
e18b890b	27	static void afs_i_init_once(void foo, struct kmem_cache cachep,
1da177e4 LT	28	unsigned long flags);
1da177e4 LT	29
454e2398 DH	30	static int afs_get_sb(struct file_system_type *fs_type,
	31	int flags, const char *dev_name,
	32	void data, struct vfsmount mnt);
1da177e4 LT	33
	34	static struct inode afs_alloc_inode(struct super_block sb);
	35
	36	static void afs_put_super(struct super_block *sb);
	37
	38	static void afs_destroy_inode(struct inode *inode);
	39
1f5ce9e9	40	struct file_system_type afs_fs_type = {
1da177e4 LT	41	.owner = THIS_MODULE,
	42	.name = "afs",
	43	.get_sb = afs_get_sb,
	44	.kill_sb = kill_anon_super,
	45	.fs_flags = FS_BINARY_MOUNTDATA,
	46	};
	47
ee9b6d61	48	static const struct super_operations afs_super_ops = {
1da177e4 LT	49	.statfs = simple_statfs,
	50	.alloc_inode = afs_alloc_inode,
	51	.drop_inode = generic_delete_inode,
	52	.destroy_inode = afs_destroy_inode,
	53	.clear_inode = afs_clear_inode,
08e0e7c8	54	.umount_begin = afs_umount_begin,
1da177e4 LT	55	.put_super = afs_put_super,
	56	};
	57
e18b890b	58	static struct kmem_cache *afs_inode_cachep;
1da177e4 LT	59	static atomic_t afs_count_active_inodes;
1da177e4 LT	60
1da177e4 LT	61	/*
	62	* initialise the filesystem
	63	*/
	64	int __init afs_fs_init(void)
	65	{
	66	int ret;
	67
	68	_enter("");
	69
1da177e4 LT	70	/* create ourselves an inode cache */
	71	atomic_set(&afs_count_active_inodes, 0);
	72
	73	ret = -ENOMEM;
	74	afs_inode_cachep = kmem_cache_create("afs_inode_cache",
	75	sizeof(struct afs_vnode),
	76	0,
	77	SLAB_HWCACHE_ALIGN,
	78	afs_i_init_once,
	79	NULL);
	80	if (!afs_inode_cachep) {
	81	printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n");
	82	return ret;
	83	}
	84
	85	/* now export our filesystem to lesser mortals */
	86	ret = register_filesystem(&afs_fs_type);
	87	if (ret < 0) {
	88	kmem_cache_destroy(afs_inode_cachep);
08e0e7c8	89	_leave(" = %d", ret);
1da177e4 LT	90	return ret;
	91	}
	92
08e0e7c8	93	_leave(" = 0");
1da177e4	94	return 0;
ec26815a	95	}
1da177e4	96
1da177e4 LT	97	/*
	98	* clean up the filesystem
	99	*/
	100	void __exit afs_fs_exit(void)
	101	{
08e0e7c8 DH	102	_enter("");
	103
	104	afs_mntpt_kill_timer();
1da177e4 LT	105	unregister_filesystem(&afs_fs_type);
	106
	107	if (atomic_read(&afs_count_active_inodes) != 0) {
	108	printk("kAFS: %d active inode objects still present\n",
	109	atomic_read(&afs_count_active_inodes));
	110	BUG();
	111	}
	112
	113	kmem_cache_destroy(afs_inode_cachep);
08e0e7c8	114	_leave("");
ec26815a	115	}
1da177e4	116
1da177e4 LT	117	/*
	118	* check that an argument has a value
	119	*/
	120	static int want_arg(char *_value, const char option)
	121	{
	122	if (!_value \|\| !_value \|\| !*_value) {
	123	printk(KERN_NOTICE "kAFS: %s: argument missing\n", option);
	124	return 0;
	125	}
	126	return 1;
ec26815a	127	}
1da177e4	128
1da177e4 LT	129	/*
	130	* check that there's no subsequent value
	131	*/
	132	static int want_no_value(char const _value, const char *option)
	133	{
	134	if (_value && *_value) {
	135	printk(KERN_NOTICE "kAFS: %s: Invalid argument: %s\n",
	136	option, *_value);
	137	return 0;
	138	}
	139	return 1;
ec26815a	140	}
1da177e4	141
1da177e4 LT	142	/*
	143	* parse the mount options
	144	* - this function has been shamelessly adapted from the ext3 fs which
	145	* shamelessly adapted it from the msdos fs
	146	*/
00d3b7a4 DH	147	static int afs_parse_options(struct afs_mount_params *params,
00d3b7a4 DH	148	char options, const char *devname)
1da177e4	149	{
08e0e7c8	150	struct afs_cell *cell;
1da177e4 LT	151	char key, value;
	152	int ret;
	153
	154	_enter("%s", options);
	155
	156	options[PAGE_SIZE - 1] = 0;
	157
	158	ret = 0;
08e0e7c8	159	while ((key = strsep(&options, ","))) {
1da177e4 LT	160	value = strchr(key, '=');
	161	if (value)
	162	*value++ = 0;
	163
08e0e7c8	164	_debug("kAFS: KEY: %s, VAL:%s", key, value ?: "-");
1da177e4 LT	165
	166	if (strcmp(key, "rwpath") == 0) {
	167	if (!want_no_value(&value, "rwpath"))
	168	return -EINVAL;
	169	params->rwpath = 1;
ec26815a	170	} else if (strcmp(key, "vol") == 0) {
1da177e4 LT	171	if (!want_arg(&value, "vol"))
	172	return -EINVAL;
	173	*devname = value;
ec26815a	174	} else if (strcmp(key, "cell") == 0) {
1da177e4 LT	175	if (!want_arg(&value, "cell"))
1da177e4 LT	176	return -EINVAL;
08e0e7c8 DH	177	cell = afs_cell_lookup(value, strlen(value));
	178	if (IS_ERR(cell))
	179	return PTR_ERR(cell);
00d3b7a4 DH	180	afs_put_cell(params->cell);
00d3b7a4 DH	181	params->cell = cell;
08e0e7c8 DH	182	} else {
	183	printk("kAFS: Unknown mount option: '%s'\n", key);
	184	ret = -EINVAL;
	185	goto error;
1da177e4	186	}
1da177e4 LT	187	}
	188
	189	ret = 0;
ec26815a	190	error:
1da177e4 LT	191	_leave(" = %d", ret);
1da177e4 LT	192	return ret;
ec26815a	193	}
1da177e4	194
00d3b7a4 DH	195	/*
	196	* parse a device name to get cell name, volume name, volume type and R/W
	197	* selector
	198	* - this can be one of the following:
	199	* "%[cell:]volume[.]" R/W volume
	200	* "#[cell:]volume[.]" R/O or R/W volume (rwpath=0),
	201	* or R/W (rwpath=1) volume
	202	* "%[cell:]volume.readonly" R/O volume
	203	* "#[cell:]volume.readonly" R/O volume
	204	* "%[cell:]volume.backup" Backup volume
	205	* "#[cell:]volume.backup" Backup volume
	206	*/
	207	static int afs_parse_device_name(struct afs_mount_params *params,
	208	const char *name)
	209	{
	210	struct afs_cell *cell;
	211	const char cellname, suffix;
	212	int cellnamesz;
	213
	214	_enter(",%s", name);
	215
	216	if (!name) {
	217	printk(KERN_ERR "kAFS: no volume name specified\n");
	218	return -EINVAL;
	219	}
	220
	221	if ((name[0] != '%' && name[0] != '#') \|\| !name[1]) {
	222	printk(KERN_ERR "kAFS: unparsable volume name\n");
	223	return -EINVAL;
	224	}
	225
	226	/* determine the type of volume we're looking for */
	227	params->type = AFSVL_ROVOL;
	228	params->force = false;
	229	if (params->rwpath \|\| name[0] == '%') {
	230	params->type = AFSVL_RWVOL;
	231	params->force = true;
	232	}
	233	name++;
	234
	235	/* split the cell name out if there is one */
	236	params->volname = strchr(name, ':');
	237	if (params->volname) {
	238	cellname = name;
	239	cellnamesz = params->volname - name;
	240	params->volname++;
	241	} else {
	242	params->volname = name;
	243	cellname = NULL;
	244	cellnamesz = 0;
	245	}
	246
	247	/* the volume type is further affected by a possible suffix */
	248	suffix = strrchr(params->volname, '.');
	249	if (suffix) {
	250	if (strcmp(suffix, ".readonly") == 0) {
	251	params->type = AFSVL_ROVOL;
	252	params->force = true;
	253	} else if (strcmp(suffix, ".backup") == 0) {
	254	params->type = AFSVL_BACKVOL;
	255	params->force = true;
	256	} else if (suffix[1] == 0) {
	257	} else {
	258	suffix = NULL;
259	}
260	}
261
262	params->volnamesz = suffix ?
263	suffix - params->volname : strlen(params->volname);
264
265	_debug("cell %.s [%p]",
266	cellnamesz, cellnamesz, cellname ?: "", params->cell);
267
268	/* lookup the cell record */
269	if (cellname \|\| !params->cell) {
270	cell = afs_cell_lookup(cellname, cellnamesz);
271	if (IS_ERR(cell)) {
272	printk(KERN_ERR "kAFS: unable to lookup cell '%s'\n",
273	cellname ?: "");
274	return PTR_ERR(cell);
275	}
276	afs_put_cell(params->cell);
277	params->cell = cell;
278	}
279
280	_debug("CELL:%s [%p] VOLUME:%.s SUFFIX:%s TYPE:%d%s",
281	params->cell->name, params->cell,
282	params->volnamesz, params->volnamesz, params->volname,
283	suffix ?: "-", params->type, params->force ? " FORCE" : "");
284
285	return 0;
286	}
287
1da177e4 LT	288	/*
	289	* check a superblock to see if it's the one we're looking for
	290	*/
	291	static int afs_test_super(struct super_block sb, void data)
	292	{
	293	struct afs_mount_params *params = data;
	294	struct afs_super_info *as = sb->s_fs_info;
	295
	296	return as->volume == params->volume;
ec26815a	297	}
1da177e4	298
1da177e4 LT	299	/*
	300	* fill in the superblock
	301	*/
436058a4	302	static int afs_fill_super(struct super_block sb, void data)
1da177e4 LT	303	{
	304	struct afs_mount_params *params = data;
	305	struct afs_super_info *as = NULL;
	306	struct afs_fid fid;
	307	struct dentry *root = NULL;
	308	struct inode *inode = NULL;
	309	int ret;
	310
08e0e7c8	311	_enter("");
1da177e4 LT	312
1da177e4 LT	313	/* allocate a superblock info record */
b593e48d	314	as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
1da177e4 LT	315	if (!as) {
	316	_leave(" = -ENOMEM");
	317	return -ENOMEM;
	318	}
	319
1da177e4 LT	320	afs_get_volume(params->volume);
	321	as->volume = params->volume;
	322
	323	/* fill in the superblock */
	324	sb->s_blocksize = PAGE_CACHE_SIZE;
	325	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	326	sb->s_magic = AFS_FS_MAGIC;
	327	sb->s_op = &afs_super_ops;
	328	sb->s_fs_info = as;
	329
	330	/* allocate the root inode and dentry */
	331	fid.vid = as->volume->vid;
	332	fid.vnode = 1;
	333	fid.unique = 1;
00d3b7a4	334	inode = afs_iget(sb, params->key, &fid);
08e0e7c8 DH	335	if (IS_ERR(inode))
08e0e7c8 DH	336	goto error_inode;
1da177e4 LT	337
	338	ret = -ENOMEM;
	339	root = d_alloc_root(inode);
	340	if (!root)
	341	goto error;
	342
	343	sb->s_root = root;
	344
08e0e7c8	345	_leave(" = 0");
1da177e4 LT	346	return 0;
1da177e4 LT	347
08e0e7c8 DH	348	error_inode:
	349	ret = PTR_ERR(inode);
	350	inode = NULL;
ec26815a	351	error:
1da177e4 LT	352	iput(inode);
	353	afs_put_volume(as->volume);
	354	kfree(as);
	355
	356	sb->s_fs_info = NULL;
	357
08e0e7c8	358	_leave(" = %d", ret);
1da177e4	359	return ret;
ec26815a	360	}
1da177e4	361
1da177e4 LT	362	/*
	363	* get an AFS superblock
	364	* - TODO: don't use get_sb_nodev(), but rather call sget() directly
	365	*/
454e2398 DH	366	static int afs_get_sb(struct file_system_type *fs_type,
	367	int flags,
	368	const char *dev_name,
	369	void *options,
	370	struct vfsmount *mnt)
1da177e4 LT	371	{
	372	struct afs_mount_params params;
	373	struct super_block *sb;
08e0e7c8	374	struct afs_volume *vol;
00d3b7a4	375	struct key *key;
1da177e4 LT	376	int ret;
	377
	378	_enter(",,%s,%p", dev_name, options);
	379
	380	memset(&params, 0, sizeof(params));
	381
00d3b7a4	382	/* parse the options and device name */
1da177e4	383	if (options) {
00d3b7a4	384	ret = afs_parse_options(&params, options, &dev_name);
1da177e4 LT	385	if (ret < 0)
1da177e4 LT	386	goto error;
1da177e4 LT	387	}
1da177e4 LT	388
00d3b7a4 DH	389
	390	ret = afs_parse_device_name(&params, dev_name);
	391	if (ret < 0)
	392	goto error;
	393
	394	/* try and do the mount securely */
	395	key = afs_request_key(params.cell);
	396	if (IS_ERR(key)) {
	397	_leave(" = %ld [key]", PTR_ERR(key));
	398	ret = PTR_ERR(key);
	399	goto error;
	400	}
	401	params.key = key;
	402
1da177e4	403	/* parse the device name */
00d3b7a4	404	vol = afs_volume_lookup(&params);
08e0e7c8 DH	405	if (IS_ERR(vol)) {
08e0e7c8 DH	406	ret = PTR_ERR(vol);
1da177e4	407	goto error;
08e0e7c8	408	}
08e0e7c8	409	params.volume = vol;
1da177e4 LT	410
	411	/* allocate a deviceless superblock */
	412	sb = sget(fs_type, afs_test_super, set_anon_super, &params);
08e0e7c8 DH	413	if (IS_ERR(sb)) {
08e0e7c8 DH	414	ret = PTR_ERR(sb);
1da177e4	415	goto error;
08e0e7c8	416	}
1da177e4	417
436058a4 DH	418	if (!sb->s_root) {
	419	/* initial superblock/root creation */
	420	_debug("create");
	421	sb->s_flags = flags;
	422	ret = afs_fill_super(sb, &params);
	423	if (ret < 0) {
	424	up_write(&sb->s_umount);
	425	deactivate_super(sb);
	426	goto error;
	427	}
	428	sb->s_flags \|= MS_ACTIVE;
	429	} else {
	430	_debug("reuse");
	431	ASSERTCMP(sb->s_flags, &, MS_ACTIVE);
1da177e4	432	}
1da177e4	433
436058a4	434	simple_set_mnt(mnt, sb);
1da177e4	435	afs_put_volume(params.volume);
00d3b7a4	436	afs_put_cell(params.cell);
08e0e7c8	437	_leave(" = 0 [%p]", sb);
454e2398	438	return 0;
1da177e4	439
ec26815a	440	error:
1da177e4	441	afs_put_volume(params.volume);
00d3b7a4 DH	442	afs_put_cell(params.cell);
00d3b7a4 DH	443	key_put(params.key);
1da177e4	444	_leave(" = %d", ret);
454e2398	445	return ret;
ec26815a	446	}
1da177e4	447
1da177e4 LT	448	/*
	449	* finish the unmounting process on the superblock
	450	*/
	451	static void afs_put_super(struct super_block *sb)
	452	{
	453	struct afs_super_info *as = sb->s_fs_info;
	454
	455	_enter("");
	456
	457	afs_put_volume(as->volume);
1da177e4 LT	458
1da177e4 LT	459	_leave("");
ec26815a	460	}
1da177e4	461
1da177e4 LT	462	/*
	463	* initialise an inode cache slab element prior to any use
	464	*/
e18b890b	465	static void afs_i_init_once(void _vnode, struct kmem_cache cachep,
1da177e4 LT	466	unsigned long flags)
1da177e4 LT	467	{
ec26815a	468	struct afs_vnode *vnode = _vnode;
1da177e4 LT	469
	470	if ((flags & (SLAB_CTOR_VERIFY\|SLAB_CTOR_CONSTRUCTOR)) ==
	471	SLAB_CTOR_CONSTRUCTOR) {
	472	memset(vnode, 0, sizeof(*vnode));
	473	inode_init_once(&vnode->vfs_inode);
	474	init_waitqueue_head(&vnode->update_waitq);
00d3b7a4	475	mutex_init(&vnode->permits_lock);
1da177e4	476	spin_lock_init(&vnode->lock);
08e0e7c8 DH	477	INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
08e0e7c8 DH	478	mutex_init(&vnode->cb_broken_lock);
1da177e4	479	}
ec26815a	480	}
1da177e4	481
1da177e4 LT	482	/*
	483	* allocate an AFS inode struct from our slab cache
	484	*/
	485	static struct inode afs_alloc_inode(struct super_block sb)
	486	{
	487	struct afs_vnode *vnode;
	488
ec26815a	489	vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
1da177e4 LT	490	if (!vnode)
	491	return NULL;
	492
	493	atomic_inc(&afs_count_active_inodes);
	494
	495	memset(&vnode->fid, 0, sizeof(vnode->fid));
	496	memset(&vnode->status, 0, sizeof(vnode->status));
	497
	498	vnode->volume = NULL;
	499	vnode->update_cnt = 0;
	500	vnode->flags = 0;
08e0e7c8	501	vnode->cb_promised = false;
1da177e4 LT	502
1da177e4 LT	503	return &vnode->vfs_inode;
ec26815a	504	}
1da177e4	505
1da177e4 LT	506	/*
	507	* destroy an AFS inode struct
	508	*/
	509	static void afs_destroy_inode(struct inode *inode)
	510	{
08e0e7c8 DH	511	struct afs_vnode *vnode = AFS_FS_I(inode);
08e0e7c8 DH	512
1da177e4 LT	513	_enter("{%lu}", inode->i_ino);
1da177e4 LT	514
08e0e7c8 DH	515	_debug("DESTROY INODE %p", inode);
	516
	517	ASSERTCMP(vnode->server, ==, NULL);
	518
	519	kmem_cache_free(afs_inode_cachep, vnode);
1da177e4	520	atomic_dec(&afs_count_active_inodes);
ec26815a	521	}