[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 <[email protected]>
 *          David Woodhouse <[email protected]>
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mount.h>
#include <linux/init.h>
#include <linux/slab.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 struct dentry *afs_mount(struct file_system_type *fs_type,
		      int flags, const char *dev_name, void *data);
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",
	.mount		= afs_mount,
	.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_d_op = &afs_fs_dentry_operations;
	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 struct dentry *afs_mount(struct file_system_type *fs_type,
		      int flags, const char *dev_name, void *options)
{
	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);
	}

	afs_put_volume(params.volume);
	afs_put_cell(params.cell);
	kfree(new_opts);
	_leave(" = 0 [%p]", sb);
	return dget(sb->s_root);

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

static void afs_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	struct afs_vnode *vnode = AFS_FS_I(inode);
	INIT_LIST_HEAD(&inode->i_dentry);
	kmem_cache_free(afs_inode_cachep, vnode);
}

/*
 * 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);

	call_rcu(&inode->i_rcu, afs_i_callback);
	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 <[email protected]>
44d1b980	13	* David Woodhouse <[email protected]>
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>
	21	#include <linux/slab.h>
	22	#include <linux/fs.h>
	23	#include <linux/pagemap.h>
80c72fe4	24	#include <linux/parser.h>
45222b9e	25	#include <linux/statfs.h>
e8edc6e0	26	#include <linux/sched.h>
1da177e4 LT	27	#include "internal.h"
	28
	29	#define AFS_FS_MAGIC 0x6B414653 /* 'kAFS' */
	30
51cc5068	31	static void afs_i_init_once(void *foo);
f7442b3b AV	32	static struct dentry afs_mount(struct file_system_type fs_type,
f7442b3b AV	33	int flags, const char dev_name, void data);
1da177e4	34	static struct inode afs_alloc_inode(struct super_block sb);
1da177e4	35	static void afs_put_super(struct super_block *sb);
1da177e4	36	static void afs_destroy_inode(struct inode *inode);
45222b9e	37	static int afs_statfs(struct dentry dentry, struct kstatfs buf);
1da177e4	38
1f5ce9e9	39	struct file_system_type afs_fs_type = {
1da177e4 LT	40	.owner = THIS_MODULE,
1da177e4 LT	41	.name = "afs",
f7442b3b	42	.mount = afs_mount,
1da177e4	43	.kill_sb = kill_anon_super,
80c72fe4	44	.fs_flags = 0,
1da177e4 LT	45	};
1da177e4 LT	46
ee9b6d61	47	static const struct super_operations afs_super_ops = {
45222b9e	48	.statfs = afs_statfs,
1da177e4	49	.alloc_inode = afs_alloc_inode,
bec5eb61	50	.drop_inode = afs_drop_inode,
1da177e4	51	.destroy_inode = afs_destroy_inode,
b57922d9	52	.evict_inode = afs_evict_inode,
1da177e4	53	.put_super = afs_put_super,
969729d5	54	.show_options = generic_show_options,
1da177e4 LT	55	};
1da177e4 LT	56
e18b890b	57	static struct kmem_cache *afs_inode_cachep;
1da177e4 LT	58	static atomic_t afs_count_active_inodes;
1da177e4 LT	59
80c72fe4 DH	60	enum {
	61	afs_no_opt,
	62	afs_opt_cell,
	63	afs_opt_rwpath,
	64	afs_opt_vol,
bec5eb61	65	afs_opt_autocell,
80c72fe4 DH	66	};
80c72fe4 DH	67
a447c093	68	static const match_table_t afs_options_list = {
80c72fe4 DH	69	{ afs_opt_cell, "cell=%s" },
	70	{ afs_opt_rwpath, "rwpath" },
	71	{ afs_opt_vol, "vol=%s" },
bec5eb61	72	{ afs_opt_autocell, "autocell" },
80c72fe4 DH	73	{ afs_no_opt, NULL },
	74	};
	75
1da177e4 LT	76	/*
	77	* initialise the filesystem
	78	*/
	79	int __init afs_fs_init(void)
	80	{
	81	int ret;
	82
	83	_enter("");
	84
1da177e4 LT	85	/* create ourselves an inode cache */
	86	atomic_set(&afs_count_active_inodes, 0);
	87
	88	ret = -ENOMEM;
	89	afs_inode_cachep = kmem_cache_create("afs_inode_cache",
	90	sizeof(struct afs_vnode),
	91	0,
	92	SLAB_HWCACHE_ALIGN,
20c2df83	93	afs_i_init_once);
1da177e4 LT	94	if (!afs_inode_cachep) {
	95	printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n");
	96	return ret;
	97	}
	98
	99	/* now export our filesystem to lesser mortals */
	100	ret = register_filesystem(&afs_fs_type);
	101	if (ret < 0) {
	102	kmem_cache_destroy(afs_inode_cachep);
08e0e7c8	103	_leave(" = %d", ret);
1da177e4 LT	104	return ret;
	105	}
	106
08e0e7c8	107	_leave(" = 0");
1da177e4	108	return 0;
ec26815a	109	}
1da177e4	110
1da177e4 LT	111	/*
	112	* clean up the filesystem
	113	*/
	114	void __exit afs_fs_exit(void)
	115	{
08e0e7c8 DH	116	_enter("");
	117
	118	afs_mntpt_kill_timer();
1da177e4 LT	119	unregister_filesystem(&afs_fs_type);
	120
	121	if (atomic_read(&afs_count_active_inodes) != 0) {
	122	printk("kAFS: %d active inode objects still present\n",
	123	atomic_read(&afs_count_active_inodes));
	124	BUG();
	125	}
	126
	127	kmem_cache_destroy(afs_inode_cachep);
08e0e7c8	128	_leave("");
ec26815a	129	}
1da177e4	130
1da177e4 LT	131	/*
	132	* parse the mount options
	133	* - this function has been shamelessly adapted from the ext3 fs which
	134	* shamelessly adapted it from the msdos fs
	135	*/
00d3b7a4 DH	136	static int afs_parse_options(struct afs_mount_params *params,
00d3b7a4 DH	137	char options, const char *devname)
1da177e4	138	{
08e0e7c8	139	struct afs_cell *cell;
80c72fe4 DH	140	substring_t args[MAX_OPT_ARGS];
	141	char *p;
	142	int token;
1da177e4 LT	143
	144	_enter("%s", options);
	145
	146	options[PAGE_SIZE - 1] = 0;
	147
80c72fe4 DH	148	while ((p = strsep(&options, ","))) {
	149	if (!*p)
	150	continue;
1da177e4	151
80c72fe4 DH	152	token = match_token(p, afs_options_list, args);
	153	switch (token) {
	154	case afs_opt_cell:
	155	cell = afs_cell_lookup(args[0].from,
bec5eb61	156	args[0].to - args[0].from,
bec5eb61	157	false);
08e0e7c8 DH	158	if (IS_ERR(cell))
08e0e7c8 DH	159	return PTR_ERR(cell);
00d3b7a4 DH	160	afs_put_cell(params->cell);
00d3b7a4 DH	161	params->cell = cell;
80c72fe4 DH	162	break;
	163
	164	case afs_opt_rwpath:
	165	params->rwpath = 1;
	166	break;
	167
	168	case afs_opt_vol:
	169	*devname = args[0].from;
	170	break;
	171
bec5eb61	172	case afs_opt_autocell:
	173	params->autocell = 1;
	174	break;
	175
80c72fe4 DH	176	default:
	177	printk(KERN_ERR "kAFS:"
	178	" Unknown or invalid mount option: '%s'\n", p);
	179	return -EINVAL;
1da177e4	180	}
1da177e4 LT	181	}
1da177e4 LT	182
80c72fe4 DH	183	_leave(" = 0");
80c72fe4 DH	184	return 0;
ec26815a	185	}
1da177e4	186
00d3b7a4 DH	187	/*
	188	* parse a device name to get cell name, volume name, volume type and R/W
	189	* selector
	190	* - this can be one of the following:
	191	* "%[cell:]volume[.]" R/W volume
	192	* "#[cell:]volume[.]" R/O or R/W volume (rwpath=0),
	193	* or R/W (rwpath=1) volume
	194	* "%[cell:]volume.readonly" R/O volume
	195	* "#[cell:]volume.readonly" R/O volume
	196	* "%[cell:]volume.backup" Backup volume
	197	* "#[cell:]volume.backup" Backup volume
	198	*/
	199	static int afs_parse_device_name(struct afs_mount_params *params,
	200	const char *name)
	201	{
	202	struct afs_cell *cell;
	203	const char cellname, suffix;
	204	int cellnamesz;
	205
	206	_enter(",%s", name);
	207
	208	if (!name) {
	209	printk(KERN_ERR "kAFS: no volume name specified\n");
	210	return -EINVAL;
	211	}
	212
	213	if ((name[0] != '%' && name[0] != '#') \|\| !name[1]) {
	214	printk(KERN_ERR "kAFS: unparsable volume name\n");
	215	return -EINVAL;
	216	}
	217
	218	/* determine the type of volume we're looking for */
	219	params->type = AFSVL_ROVOL;
	220	params->force = false;
	221	if (params->rwpath \|\| name[0] == '%') {
	222	params->type = AFSVL_RWVOL;
	223	params->force = true;
	224	}
	225	name++;
	226
	227	/* split the cell name out if there is one */
	228	params->volname = strchr(name, ':');
	229	if (params->volname) {
	230	cellname = name;
	231	cellnamesz = params->volname - name;
	232	params->volname++;
	233	} else {
	234	params->volname = name;
	235	cellname = NULL;
	236	cellnamesz = 0;
	237	}
	238
	239	/* the volume type is further affected by a possible suffix */
	240	suffix = strrchr(params->volname, '.');
	241	if (suffix) {
	242	if (strcmp(suffix, ".readonly") == 0) {
	243	params->type = AFSVL_ROVOL;
	244	params->force = true;
	245	} else if (strcmp(suffix, ".backup") == 0) {
	246	params->type = AFSVL_BACKVOL;
	247	params->force = true;
	248	} else if (suffix[1] == 0) {
	249	} else {
	250	suffix = NULL;
251	}
252	}
253
254	params->volnamesz = suffix ?
255	suffix - params->volname : strlen(params->volname);
256
257	_debug("cell %.s [%p]",
258	cellnamesz, cellnamesz, cellname ?: "", params->cell);
259
260	/* lookup the cell record */
261	if (cellname \|\| !params->cell) {
bec5eb61	262	cell = afs_cell_lookup(cellname, cellnamesz, true);
00d3b7a4	263	if (IS_ERR(cell)) {
bec5eb61	264	printk(KERN_ERR "kAFS: unable to lookup cell '%.s'\n",
bec5eb61	265	cellnamesz, cellnamesz, cellname ?: "");
00d3b7a4 DH	266	return PTR_ERR(cell);
	267	}
	268	afs_put_cell(params->cell);
	269	params->cell = cell;
	270	}
	271
	272	_debug("CELL:%s [%p] VOLUME:%.s SUFFIX:%s TYPE:%d%s",
	273	params->cell->name, params->cell,
	274	params->volnamesz, params->volnamesz, params->volname,
	275	suffix ?: "-", params->type, params->force ? " FORCE" : "");
	276
	277	return 0;
	278	}
	279
1da177e4 LT	280	/*
	281	* check a superblock to see if it's the one we're looking for
	282	*/
	283	static int afs_test_super(struct super_block sb, void data)
	284	{
	285	struct afs_mount_params *params = data;
	286	struct afs_super_info *as = sb->s_fs_info;
	287
	288	return as->volume == params->volume;
ec26815a	289	}
1da177e4	290
1da177e4 LT	291	/*
	292	* fill in the superblock
	293	*/
436058a4	294	static int afs_fill_super(struct super_block sb, void data)
1da177e4 LT	295	{
	296	struct afs_mount_params *params = data;
	297	struct afs_super_info *as = NULL;
	298	struct afs_fid fid;
	299	struct dentry *root = NULL;
	300	struct inode *inode = NULL;
	301	int ret;
	302
08e0e7c8	303	_enter("");
1da177e4 LT	304
1da177e4 LT	305	/* allocate a superblock info record */
b593e48d	306	as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
1da177e4 LT	307	if (!as) {
	308	_leave(" = -ENOMEM");
	309	return -ENOMEM;
	310	}
	311
1da177e4 LT	312	afs_get_volume(params->volume);
	313	as->volume = params->volume;
	314
	315	/* fill in the superblock */
	316	sb->s_blocksize = PAGE_CACHE_SIZE;
	317	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	318	sb->s_magic = AFS_FS_MAGIC;
	319	sb->s_op = &afs_super_ops;
	320	sb->s_fs_info = as;
e1da0222	321	sb->s_bdi = &as->volume->bdi;
1da177e4 LT	322
	323	/* allocate the root inode and dentry */
	324	fid.vid = as->volume->vid;
	325	fid.vnode = 1;
	326	fid.unique = 1;
260a9803	327	inode = afs_iget(sb, params->key, &fid, NULL, NULL);
08e0e7c8 DH	328	if (IS_ERR(inode))
08e0e7c8 DH	329	goto error_inode;
1da177e4	330
bec5eb61	331	if (params->autocell)
	332	set_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(inode)->flags);
	333
1da177e4 LT	334	ret = -ENOMEM;
	335	root = d_alloc_root(inode);
	336	if (!root)
	337	goto error;
	338
d61dcce2	339	sb->s_d_op = &afs_fs_dentry_operations;
1da177e4 LT	340	sb->s_root = root;
1da177e4 LT	341
08e0e7c8	342	_leave(" = 0");
1da177e4 LT	343	return 0;
1da177e4 LT	344
08e0e7c8 DH	345	error_inode:
	346	ret = PTR_ERR(inode);
	347	inode = NULL;
ec26815a	348	error:
1da177e4 LT	349	iput(inode);
	350	afs_put_volume(as->volume);
	351	kfree(as);
	352
	353	sb->s_fs_info = NULL;
	354
08e0e7c8	355	_leave(" = %d", ret);
1da177e4	356	return ret;
ec26815a	357	}
1da177e4	358
1da177e4 LT	359	/*
1da177e4 LT	360	* get an AFS superblock
1da177e4	361	*/
f7442b3b AV	362	static struct dentry afs_mount(struct file_system_type fs_type,
f7442b3b AV	363	int flags, const char dev_name, void options)
1da177e4 LT	364	{
	365	struct afs_mount_params params;
	366	struct super_block *sb;
08e0e7c8	367	struct afs_volume *vol;
00d3b7a4	368	struct key *key;
969729d5	369	char *new_opts = kstrdup(options, GFP_KERNEL);
1da177e4 LT	370	int ret;
	371
	372	_enter(",,%s,%p", dev_name, options);
	373
	374	memset(&params, 0, sizeof(params));
	375
00d3b7a4	376	/* parse the options and device name */
1da177e4	377	if (options) {
00d3b7a4	378	ret = afs_parse_options(&params, options, &dev_name);
1da177e4 LT	379	if (ret < 0)
1da177e4 LT	380	goto error;
1da177e4 LT	381	}
1da177e4 LT	382
00d3b7a4 DH	383	ret = afs_parse_device_name(&params, dev_name);
	384	if (ret < 0)
	385	goto error;
	386
	387	/* try and do the mount securely */
	388	key = afs_request_key(params.cell);
	389	if (IS_ERR(key)) {
	390	_leave(" = %ld [key]", PTR_ERR(key));
	391	ret = PTR_ERR(key);
	392	goto error;
	393	}
	394	params.key = key;
	395
1da177e4	396	/* parse the device name */
00d3b7a4	397	vol = afs_volume_lookup(&params);
08e0e7c8 DH	398	if (IS_ERR(vol)) {
08e0e7c8 DH	399	ret = PTR_ERR(vol);
1da177e4	400	goto error;
08e0e7c8	401	}
08e0e7c8	402	params.volume = vol;
1da177e4 LT	403
	404	/* allocate a deviceless superblock */
	405	sb = sget(fs_type, afs_test_super, set_anon_super, &params);
08e0e7c8 DH	406	if (IS_ERR(sb)) {
08e0e7c8 DH	407	ret = PTR_ERR(sb);
1da177e4	408	goto error;
08e0e7c8	409	}
1da177e4	410
436058a4 DH	411	if (!sb->s_root) {
	412	/* initial superblock/root creation */
	413	_debug("create");
	414	sb->s_flags = flags;
	415	ret = afs_fill_super(sb, &params);
	416	if (ret < 0) {
6f5bbff9	417	deactivate_locked_super(sb);
436058a4 DH	418	goto error;
436058a4 DH	419	}
2a32cebd	420	save_mount_options(sb, new_opts);
436058a4 DH	421	sb->s_flags \|= MS_ACTIVE;
	422	} else {
	423	_debug("reuse");
	424	ASSERTCMP(sb->s_flags, &, MS_ACTIVE);
1da177e4	425	}
1da177e4 LT	426
1da177e4 LT	427	afs_put_volume(params.volume);
00d3b7a4	428	afs_put_cell(params.cell);
2a32cebd	429	kfree(new_opts);
08e0e7c8	430	_leave(" = 0 [%p]", sb);
f7442b3b	431	return dget(sb->s_root);
1da177e4	432
ec26815a	433	error:
1da177e4	434	afs_put_volume(params.volume);
00d3b7a4 DH	435	afs_put_cell(params.cell);
00d3b7a4 DH	436	key_put(params.key);
969729d5	437	kfree(new_opts);
1da177e4	438	_leave(" = %d", ret);
f7442b3b	439	return ERR_PTR(ret);
ec26815a	440	}
1da177e4	441
1da177e4 LT	442	/*
	443	* finish the unmounting process on the superblock
	444	*/
	445	static void afs_put_super(struct super_block *sb)
	446	{
	447	struct afs_super_info *as = sb->s_fs_info;
	448
	449	_enter("");
	450
	451	afs_put_volume(as->volume);
1da177e4 LT	452
1da177e4 LT	453	_leave("");
ec26815a	454	}
1da177e4	455
1da177e4 LT	456	/*
	457	* initialise an inode cache slab element prior to any use
	458	*/
51cc5068	459	static void afs_i_init_once(void *_vnode)
1da177e4	460	{
ec26815a	461	struct afs_vnode *vnode = _vnode;
1da177e4	462
a35afb83 CL	463	memset(vnode, 0, sizeof(*vnode));
	464	inode_init_once(&vnode->vfs_inode);
	465	init_waitqueue_head(&vnode->update_waitq);
	466	mutex_init(&vnode->permits_lock);
	467	mutex_init(&vnode->validate_lock);
	468	spin_lock_init(&vnode->writeback_lock);
	469	spin_lock_init(&vnode->lock);
	470	INIT_LIST_HEAD(&vnode->writebacks);
e8d6c554 DH	471	INIT_LIST_HEAD(&vnode->pending_locks);
	472	INIT_LIST_HEAD(&vnode->granted_locks);
	473	INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);
a35afb83	474	INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
ec26815a	475	}
1da177e4	476
1da177e4 LT	477	/*
	478	* allocate an AFS inode struct from our slab cache
	479	*/
	480	static struct inode afs_alloc_inode(struct super_block sb)
	481	{
	482	struct afs_vnode *vnode;
	483
ec26815a	484	vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
1da177e4 LT	485	if (!vnode)
	486	return NULL;
	487
	488	atomic_inc(&afs_count_active_inodes);
	489
	490	memset(&vnode->fid, 0, sizeof(vnode->fid));
	491	memset(&vnode->status, 0, sizeof(vnode->status));
	492
	493	vnode->volume = NULL;
	494	vnode->update_cnt = 0;
260a9803	495	vnode->flags = 1 << AFS_VNODE_UNSET;
08e0e7c8	496	vnode->cb_promised = false;
1da177e4	497
0f300ca9	498	_leave(" = %p", &vnode->vfs_inode);
1da177e4	499	return &vnode->vfs_inode;
ec26815a	500	}
1da177e4	501
fa0d7e3d NP	502	static void afs_i_callback(struct rcu_head *head)
	503	{
	504	struct inode *inode = container_of(head, struct inode, i_rcu);
	505	struct afs_vnode *vnode = AFS_FS_I(inode);
	506	INIT_LIST_HEAD(&inode->i_dentry);
	507	kmem_cache_free(afs_inode_cachep, vnode);
	508	}
	509
1da177e4 LT	510	/*
	511	* destroy an AFS inode struct
	512	*/
	513	static void afs_destroy_inode(struct inode *inode)
	514	{
08e0e7c8 DH	515	struct afs_vnode *vnode = AFS_FS_I(inode);
08e0e7c8 DH	516
0f300ca9	517	_enter("%p{%x:%u}", inode, vnode->fid.vid, vnode->fid.vnode);
1da177e4	518
08e0e7c8 DH	519	_debug("DESTROY INODE %p", inode);
	520
	521	ASSERTCMP(vnode->server, ==, NULL);
	522
fa0d7e3d	523	call_rcu(&inode->i_rcu, afs_i_callback);
1da177e4	524	atomic_dec(&afs_count_active_inodes);
ec26815a	525	}
45222b9e DH	526
	527	/*
	528	* return information about an AFS volume
	529	*/
	530	static int afs_statfs(struct dentry dentry, struct kstatfs buf)
	531	{
	532	struct afs_volume_status vs;
	533	struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
	534	struct key *key;
	535	int ret;
	536
	537	key = afs_request_key(vnode->volume->cell);
	538	if (IS_ERR(key))
	539	return PTR_ERR(key);
	540
	541	ret = afs_vnode_get_volume_status(vnode, key, &vs);
	542	key_put(key);
	543	if (ret < 0) {
	544	_leave(" = %d", ret);
	545	return ret;
	546	}
	547
	548	buf->f_type = dentry->d_sb->s_magic;
	549	buf->f_bsize = AFS_BLOCK_SIZE;
	550	buf->f_namelen = AFSNAMEMAX - 1;
	551
	552	if (vs.max_quota == 0)
	553	buf->f_blocks = vs.part_max_blocks;
	554	else
	555	buf->f_blocks = vs.max_quota;
	556	buf->f_bavail = buf->f_bfree = buf->f_blocks - vs.blocks_in_use;
	557	return 0;
	558	}