[deliverable/linux.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@infradead.org>
 *
 */

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

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

static void afs_i_init_once(void *foo);
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);
static int afs_statfs(struct dentry *dentry, struct kstatfs *buf);

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		= afs_statfs,
	.alloc_inode	= afs_alloc_inode,
	.drop_inode	= afs_drop_inode,
	.destroy_inode	= afs_destroy_inode,
	.evict_inode	= afs_evict_inode,
	.put_super	= afs_put_super,
	.show_options	= generic_show_options,
};

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,
	afs_opt_autocell,
};

static const match_table_t afs_options_list = {
	{ afs_opt_cell,		"cell=%s"	},
	{ afs_opt_rwpath,	"rwpath"	},
	{ afs_opt_vol,		"vol=%s"	},
	{ afs_opt_autocell,	"autocell"	},
	{ 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);
	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,
					       false);
			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;

		case afs_opt_autocell:
			params->autocell = 1;
			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, true);
		if (IS_ERR(cell)) {
			printk(KERN_ERR "kAFS: unable to lookup cell '%*.*s'\n",
			       cellnamesz, cellnamesz, 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;
	sb->s_bdi		= &as->volume->bdi;

	/* 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;

	if (params->autocell)
		set_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(inode)->flags);

	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;
	char *new_opts = kstrdup(options, GFP_KERNEL);
	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) {
			deactivate_locked_super(sb);
			goto error;
		}
		save_mount_options(sb, new_opts);
		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);
	kfree(new_opts);
	_leave(" = 0 [%p]", sb);
	return 0;

error:
	afs_put_volume(params.volume);
	afs_put_cell(params.cell);
	key_put(params.key);
	kfree(new_opts);
	_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("");

	lock_kernel();

	afs_put_volume(as->volume);

	unlock_kernel();

	_leave("");
}

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

	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_LIST_HEAD(&vnode->pending_locks);
	INIT_LIST_HEAD(&vnode->granted_locks);
	INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);
	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;

	_leave(" = %p", &vnode->vfs_inode);
	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("%p{%x:%u}", inode, vnode->fid.vid, vnode->fid.vnode);

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

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

	kmem_cache_free(afs_inode_cachep, vnode);
	atomic_dec(&afs_count_active_inodes);
}

/*
 * return information about an AFS volume
 */
static int afs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct afs_volume_status vs;
	struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
	struct key *key;
	int ret;

	key = afs_request_key(vnode->volume->cell);
	if (IS_ERR(key))
		return PTR_ERR(key);

	ret = afs_vnode_get_volume_status(vnode, key, &vs);
	key_put(key);
	if (ret < 0) {
		_leave(" = %d", ret);
		return ret;
	}

	buf->f_type	= dentry->d_sb->s_magic;
	buf->f_bsize	= AFS_BLOCK_SIZE;
	buf->f_namelen	= AFSNAMEMAX - 1;

	if (vs.max_quota == 0)
		buf->f_blocks = vs.part_max_blocks;
	else
		buf->f_blocks = vs.max_quota;
	buf->f_bavail = buf->f_bfree = buf->f_blocks - vs.blocks_in_use;
	return 0;
}
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>
44d1b980	13	* David Woodhouse <dwmw2@infradead.org>
1da177e4 LT	14	*
	15	*/
	16
	17	#include <linux/kernel.h>
	18	#include <linux/module.h>
bec5eb61	19	#include <linux/mount.h>
1da177e4 LT	20	#include <linux/init.h>
1da177e4 LT	21	#include <linux/slab.h>
405f5571	22	#include <linux/smp_lock.h>
1da177e4 LT	23	#include <linux/fs.h>
1da177e4 LT	24	#include <linux/pagemap.h>
80c72fe4	25	#include <linux/parser.h>
45222b9e	26	#include <linux/statfs.h>
e8edc6e0	27	#include <linux/sched.h>
1da177e4 LT	28	#include "internal.h"
	29
	30	#define AFS_FS_MAGIC 0x6B414653 /* 'kAFS' */
	31
51cc5068	32	static void afs_i_init_once(void *foo);
454e2398 DH	33	static int afs_get_sb(struct file_system_type *fs_type,
	34	int flags, const char *dev_name,
	35	void data, struct vfsmount mnt);
1da177e4	36	static struct inode afs_alloc_inode(struct super_block sb);
1da177e4	37	static void afs_put_super(struct super_block *sb);
1da177e4	38	static void afs_destroy_inode(struct inode *inode);
45222b9e	39	static int afs_statfs(struct dentry dentry, struct kstatfs buf);
1da177e4	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 = {
45222b9e	50	.statfs = afs_statfs,
1da177e4	51	.alloc_inode = afs_alloc_inode,
bec5eb61	52	.drop_inode = afs_drop_inode,
1da177e4	53	.destroy_inode = afs_destroy_inode,
b57922d9	54	.evict_inode = afs_evict_inode,
1da177e4	55	.put_super = afs_put_super,
969729d5	56	.show_options = generic_show_options,
1da177e4 LT	57	};
1da177e4 LT	58
e18b890b	59	static struct kmem_cache *afs_inode_cachep;
1da177e4 LT	60	static atomic_t afs_count_active_inodes;
1da177e4 LT	61
80c72fe4 DH	62	enum {
	63	afs_no_opt,
	64	afs_opt_cell,
	65	afs_opt_rwpath,
	66	afs_opt_vol,
bec5eb61	67	afs_opt_autocell,
80c72fe4 DH	68	};
80c72fe4 DH	69
a447c093	70	static const 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" },
bec5eb61	74	{ afs_opt_autocell, "autocell" },
80c72fe4 DH	75	{ afs_no_opt, NULL },
	76	};
	77
1da177e4 LT	78	/*
	79	* initialise the filesystem
	80	*/
	81	int __init afs_fs_init(void)
	82	{
	83	int ret;
	84
	85	_enter("");
	86
1da177e4 LT	87	/* create ourselves an inode cache */
	88	atomic_set(&afs_count_active_inodes, 0);
	89
	90	ret = -ENOMEM;
	91	afs_inode_cachep = kmem_cache_create("afs_inode_cache",
	92	sizeof(struct afs_vnode),
	93	0,
	94	SLAB_HWCACHE_ALIGN,
20c2df83	95	afs_i_init_once);
1da177e4 LT	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,
bec5eb61	158	args[0].to - args[0].from,
bec5eb61	159	false);
08e0e7c8 DH	160	if (IS_ERR(cell))
08e0e7c8 DH	161	return PTR_ERR(cell);
00d3b7a4 DH	162	afs_put_cell(params->cell);
00d3b7a4 DH	163	params->cell = cell;
80c72fe4 DH	164	break;
	165
	166	case afs_opt_rwpath:
	167	params->rwpath = 1;
	168	break;
	169
	170	case afs_opt_vol:
	171	*devname = args[0].from;
	172	break;
	173
bec5eb61	174	case afs_opt_autocell:
	175	params->autocell = 1;
	176	break;
	177
80c72fe4 DH	178	default:
	179	printk(KERN_ERR "kAFS:"
	180	" Unknown or invalid mount option: '%s'\n", p);
	181	return -EINVAL;
1da177e4	182	}
1da177e4 LT	183	}
1da177e4 LT	184
80c72fe4 DH	185	_leave(" = 0");
80c72fe4 DH	186	return 0;
ec26815a	187	}
1da177e4	188
00d3b7a4 DH	189	/*
	190	* parse a device name to get cell name, volume name, volume type and R/W
	191	* selector
	192	* - this can be one of the following:
	193	* "%[cell:]volume[.]" R/W volume
	194	* "#[cell:]volume[.]" R/O or R/W volume (rwpath=0),
	195	* or R/W (rwpath=1) volume
	196	* "%[cell:]volume.readonly" R/O volume
	197	* "#[cell:]volume.readonly" R/O volume
	198	* "%[cell:]volume.backup" Backup volume
	199	* "#[cell:]volume.backup" Backup volume
	200	*/
	201	static int afs_parse_device_name(struct afs_mount_params *params,
	202	const char *name)
	203	{
	204	struct afs_cell *cell;
	205	const char cellname, suffix;
	206	int cellnamesz;
	207
	208	_enter(",%s", name);
	209
	210	if (!name) {
	211	printk(KERN_ERR "kAFS: no volume name specified\n");
	212	return -EINVAL;
	213	}
	214
	215	if ((name[0] != '%' && name[0] != '#') \|\| !name[1]) {
	216	printk(KERN_ERR "kAFS: unparsable volume name\n");
	217	return -EINVAL;
	218	}
	219
	220	/* determine the type of volume we're looking for */
	221	params->type = AFSVL_ROVOL;
	222	params->force = false;
	223	if (params->rwpath \|\| name[0] == '%') {
	224	params->type = AFSVL_RWVOL;
	225	params->force = true;
	226	}
	227	name++;
	228
	229	/* split the cell name out if there is one */
	230	params->volname = strchr(name, ':');
	231	if (params->volname) {
	232	cellname = name;
	233	cellnamesz = params->volname - name;
	234	params->volname++;
	235	} else {
	236	params->volname = name;
	237	cellname = NULL;
	238	cellnamesz = 0;
	239	}
	240
	241	/* the volume type is further affected by a possible suffix */
	242	suffix = strrchr(params->volname, '.');
	243	if (suffix) {
	244	if (strcmp(suffix, ".readonly") == 0) {
	245	params->type = AFSVL_ROVOL;
	246	params->force = true;
	247	} else if (strcmp(suffix, ".backup") == 0) {
	248	params->type = AFSVL_BACKVOL;
	249	params->force = true;
	250	} else if (suffix[1] == 0) {
	251	} else {
	252	suffix = NULL;
253	}
254	}
255
256	params->volnamesz = suffix ?
257	suffix - params->volname : strlen(params->volname);
258
259	_debug("cell %.s [%p]",
260	cellnamesz, cellnamesz, cellname ?: "", params->cell);
261
262	/* lookup the cell record */
263	if (cellname \|\| !params->cell) {
bec5eb61	264	cell = afs_cell_lookup(cellname, cellnamesz, true);
00d3b7a4	265	if (IS_ERR(cell)) {
bec5eb61	266	printk(KERN_ERR "kAFS: unable to lookup cell '%.s'\n",
bec5eb61	267	cellnamesz, cellnamesz, cellname ?: "");
00d3b7a4 DH	268	return PTR_ERR(cell);
	269	}
	270	afs_put_cell(params->cell);
	271	params->cell = cell;
	272	}
	273
	274	_debug("CELL:%s [%p] VOLUME:%.s SUFFIX:%s TYPE:%d%s",
	275	params->cell->name, params->cell,
	276	params->volnamesz, params->volnamesz, params->volname,
	277	suffix ?: "-", params->type, params->force ? " FORCE" : "");
	278
	279	return 0;
	280	}
	281
1da177e4 LT	282	/*
	283	* check a superblock to see if it's the one we're looking for
	284	*/
	285	static int afs_test_super(struct super_block sb, void data)
	286	{
	287	struct afs_mount_params *params = data;
	288	struct afs_super_info *as = sb->s_fs_info;
	289
	290	return as->volume == params->volume;
ec26815a	291	}
1da177e4	292
1da177e4 LT	293	/*
	294	* fill in the superblock
	295	*/
436058a4	296	static int afs_fill_super(struct super_block sb, void data)
1da177e4 LT	297	{
	298	struct afs_mount_params *params = data;
	299	struct afs_super_info *as = NULL;
	300	struct afs_fid fid;
	301	struct dentry *root = NULL;
	302	struct inode *inode = NULL;
	303	int ret;
	304
08e0e7c8	305	_enter("");
1da177e4 LT	306
1da177e4 LT	307	/* allocate a superblock info record */
b593e48d	308	as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
1da177e4 LT	309	if (!as) {
	310	_leave(" = -ENOMEM");
	311	return -ENOMEM;
	312	}
	313
1da177e4 LT	314	afs_get_volume(params->volume);
	315	as->volume = params->volume;
	316
	317	/* fill in the superblock */
	318	sb->s_blocksize = PAGE_CACHE_SIZE;
	319	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	320	sb->s_magic = AFS_FS_MAGIC;
	321	sb->s_op = &afs_super_ops;
	322	sb->s_fs_info = as;
e1da0222	323	sb->s_bdi = &as->volume->bdi;
1da177e4 LT	324
	325	/* allocate the root inode and dentry */
	326	fid.vid = as->volume->vid;
	327	fid.vnode = 1;
	328	fid.unique = 1;
260a9803	329	inode = afs_iget(sb, params->key, &fid, NULL, NULL);
08e0e7c8 DH	330	if (IS_ERR(inode))
08e0e7c8 DH	331	goto error_inode;
1da177e4	332
bec5eb61	333	if (params->autocell)
	334	set_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(inode)->flags);
	335
1da177e4 LT	336	ret = -ENOMEM;
	337	root = d_alloc_root(inode);
	338	if (!root)
	339	goto error;
	340
	341	sb->s_root = root;
	342
08e0e7c8	343	_leave(" = 0");
1da177e4 LT	344	return 0;
1da177e4 LT	345
08e0e7c8 DH	346	error_inode:
	347	ret = PTR_ERR(inode);
	348	inode = NULL;
ec26815a	349	error:
1da177e4 LT	350	iput(inode);
	351	afs_put_volume(as->volume);
	352	kfree(as);
	353
	354	sb->s_fs_info = NULL;
	355
08e0e7c8	356	_leave(" = %d", ret);
1da177e4	357	return ret;
ec26815a	358	}
1da177e4	359
1da177e4 LT	360	/*
1da177e4 LT	361	* get an AFS superblock
1da177e4	362	*/
454e2398 DH	363	static int afs_get_sb(struct file_system_type *fs_type,
	364	int flags,
	365	const char *dev_name,
	366	void *options,
	367	struct vfsmount *mnt)
1da177e4 LT	368	{
	369	struct afs_mount_params params;
	370	struct super_block *sb;
08e0e7c8	371	struct afs_volume *vol;
00d3b7a4	372	struct key *key;
969729d5	373	char *new_opts = kstrdup(options, GFP_KERNEL);
1da177e4 LT	374	int ret;
	375
	376	_enter(",,%s,%p", dev_name, options);
	377
	378	memset(&params, 0, sizeof(params));
	379
00d3b7a4	380	/* parse the options and device name */
1da177e4	381	if (options) {
00d3b7a4	382	ret = afs_parse_options(&params, options, &dev_name);
1da177e4 LT	383	if (ret < 0)
1da177e4 LT	384	goto error;
1da177e4 LT	385	}
1da177e4 LT	386
00d3b7a4 DH	387	ret = afs_parse_device_name(&params, dev_name);
	388	if (ret < 0)
	389	goto error;
	390
	391	/* try and do the mount securely */
	392	key = afs_request_key(params.cell);
	393	if (IS_ERR(key)) {
	394	_leave(" = %ld [key]", PTR_ERR(key));
	395	ret = PTR_ERR(key);
	396	goto error;
	397	}
	398	params.key = key;
	399
1da177e4	400	/* parse the device name */
00d3b7a4	401	vol = afs_volume_lookup(&params);
08e0e7c8 DH	402	if (IS_ERR(vol)) {
08e0e7c8 DH	403	ret = PTR_ERR(vol);
1da177e4	404	goto error;
08e0e7c8	405	}
08e0e7c8	406	params.volume = vol;
1da177e4 LT	407
	408	/* allocate a deviceless superblock */
	409	sb = sget(fs_type, afs_test_super, set_anon_super, &params);
08e0e7c8 DH	410	if (IS_ERR(sb)) {
08e0e7c8 DH	411	ret = PTR_ERR(sb);
1da177e4	412	goto error;
08e0e7c8	413	}
1da177e4	414
436058a4 DH	415	if (!sb->s_root) {
	416	/* initial superblock/root creation */
	417	_debug("create");
	418	sb->s_flags = flags;
	419	ret = afs_fill_super(sb, &params);
	420	if (ret < 0) {
6f5bbff9	421	deactivate_locked_super(sb);
436058a4 DH	422	goto error;
436058a4 DH	423	}
2a32cebd	424	save_mount_options(sb, new_opts);
436058a4 DH	425	sb->s_flags \|= MS_ACTIVE;
	426	} else {
	427	_debug("reuse");
	428	ASSERTCMP(sb->s_flags, &, MS_ACTIVE);
1da177e4	429	}
1da177e4	430
436058a4	431	simple_set_mnt(mnt, sb);
1da177e4	432	afs_put_volume(params.volume);
00d3b7a4	433	afs_put_cell(params.cell);
2a32cebd	434	kfree(new_opts);
08e0e7c8	435	_leave(" = 0 [%p]", sb);
454e2398	436	return 0;
1da177e4	437
ec26815a	438	error:
1da177e4	439	afs_put_volume(params.volume);
00d3b7a4 DH	440	afs_put_cell(params.cell);
00d3b7a4 DH	441	key_put(params.key);
969729d5	442	kfree(new_opts);
1da177e4	443	_leave(" = %d", ret);
454e2398	444	return ret;
ec26815a	445	}
1da177e4	446
1da177e4 LT	447	/*
	448	* finish the unmounting process on the superblock
	449	*/
	450	static void afs_put_super(struct super_block *sb)
	451	{
	452	struct afs_super_info *as = sb->s_fs_info;
	453
	454	_enter("");
	455
6cfd0148 CH	456	lock_kernel();
6cfd0148 CH	457
1da177e4	458	afs_put_volume(as->volume);
1da177e4	459
6cfd0148 CH	460	unlock_kernel();
6cfd0148 CH	461
1da177e4	462	_leave("");
ec26815a	463	}
1da177e4	464
1da177e4 LT	465	/*
	466	* initialise an inode cache slab element prior to any use
	467	*/
51cc5068	468	static void afs_i_init_once(void *_vnode)
1da177e4	469	{
ec26815a	470	struct afs_vnode *vnode = _vnode;
1da177e4	471
a35afb83 CL	472	memset(vnode, 0, sizeof(*vnode));
	473	inode_init_once(&vnode->vfs_inode);
	474	init_waitqueue_head(&vnode->update_waitq);
	475	mutex_init(&vnode->permits_lock);
	476	mutex_init(&vnode->validate_lock);
	477	spin_lock_init(&vnode->writeback_lock);
	478	spin_lock_init(&vnode->lock);
	479	INIT_LIST_HEAD(&vnode->writebacks);
e8d6c554 DH	480	INIT_LIST_HEAD(&vnode->pending_locks);
	481	INIT_LIST_HEAD(&vnode->granted_locks);
	482	INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);
a35afb83	483	INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
ec26815a	484	}
1da177e4	485
1da177e4 LT	486	/*
	487	* allocate an AFS inode struct from our slab cache
	488	*/
	489	static struct inode afs_alloc_inode(struct super_block sb)
	490	{
	491	struct afs_vnode *vnode;
	492
ec26815a	493	vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
1da177e4 LT	494	if (!vnode)
	495	return NULL;
	496
	497	atomic_inc(&afs_count_active_inodes);
	498
	499	memset(&vnode->fid, 0, sizeof(vnode->fid));
	500	memset(&vnode->status, 0, sizeof(vnode->status));
	501
	502	vnode->volume = NULL;
	503	vnode->update_cnt = 0;
260a9803	504	vnode->flags = 1 << AFS_VNODE_UNSET;
08e0e7c8	505	vnode->cb_promised = false;
1da177e4	506
0f300ca9	507	_leave(" = %p", &vnode->vfs_inode);
1da177e4	508	return &vnode->vfs_inode;
ec26815a	509	}
1da177e4	510
1da177e4 LT	511	/*
	512	* destroy an AFS inode struct
	513	*/
	514	static void afs_destroy_inode(struct inode *inode)
	515	{
08e0e7c8 DH	516	struct afs_vnode *vnode = AFS_FS_I(inode);
08e0e7c8 DH	517
0f300ca9	518	_enter("%p{%x:%u}", inode, vnode->fid.vid, vnode->fid.vnode);
1da177e4	519
08e0e7c8 DH	520	_debug("DESTROY INODE %p", inode);
	521
	522	ASSERTCMP(vnode->server, ==, NULL);
	523
	524	kmem_cache_free(afs_inode_cachep, vnode);
1da177e4	525	atomic_dec(&afs_count_active_inodes);
ec26815a	526	}
45222b9e DH	527
	528	/*
	529	* return information about an AFS volume
	530	*/
	531	static int afs_statfs(struct dentry dentry, struct kstatfs buf)
	532	{
	533	struct afs_volume_status vs;
	534	struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
	535	struct key *key;
	536	int ret;
	537
	538	key = afs_request_key(vnode->volume->cell);
	539	if (IS_ERR(key))
	540	return PTR_ERR(key);
	541
	542	ret = afs_vnode_get_volume_status(vnode, key, &vs);
	543	key_put(key);
	544	if (ret < 0) {
	545	_leave(" = %d", ret);
	546	return ret;
	547	}
	548
	549	buf->f_type = dentry->d_sb->s_magic;
	550	buf->f_bsize = AFS_BLOCK_SIZE;
	551	buf->f_namelen = AFSNAMEMAX - 1;
	552
	553	if (vs.max_quota == 0)
	554	buf->f_blocks = vs.part_max_blocks;
	555	else
	556	buf->f_blocks = vs.max_quota;
	557	buf->f_bavail = buf->f_bfree = buf->f_blocks - vs.blocks_in_use;
	558	return 0;
	559	}