[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@infradead.org>
 *
 */

#include <linux/kernel.h>
#include <linux/module.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,
	.destroy_inode	= afs_destroy_inode,
	.clear_inode	= afs_clear_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,
};

static const 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);
	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;
	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;

	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>
	19	#include <linux/init.h>
	20	#include <linux/slab.h>
405f5571	21	#include <linux/smp_lock.h>
1da177e4 LT	22	#include <linux/fs.h>
1da177e4 LT	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);
454e2398 DH	32	static int afs_get_sb(struct file_system_type *fs_type,
	33	int flags, const char *dev_name,
	34	void data, struct vfsmount mnt);
1da177e4	35	static struct inode afs_alloc_inode(struct super_block sb);
1da177e4	36	static void afs_put_super(struct super_block *sb);
1da177e4	37	static void afs_destroy_inode(struct inode *inode);
45222b9e	38	static int afs_statfs(struct dentry dentry, struct kstatfs buf);
1da177e4	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,
80c72fe4	45	.fs_flags = 0,
1da177e4 LT	46	};
1da177e4 LT	47
ee9b6d61	48	static const struct super_operations afs_super_ops = {
45222b9e	49	.statfs = afs_statfs,
1da177e4	50	.alloc_inode = afs_alloc_inode,
1da177e4 LT	51	.destroy_inode = afs_destroy_inode,
	52	.clear_inode = afs_clear_inode,
	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,
	65	};
	66
a447c093	67	static const match_table_t afs_options_list = {
80c72fe4 DH	68	{ afs_opt_cell, "cell=%s" },
	69	{ afs_opt_rwpath, "rwpath" },
	70	{ afs_opt_vol, "vol=%s" },
	71	{ afs_no_opt, NULL },
	72	};
	73
1da177e4 LT	74	/*
	75	* initialise the filesystem
	76	*/
	77	int __init afs_fs_init(void)
	78	{
	79	int ret;
	80
	81	_enter("");
	82
1da177e4 LT	83	/* create ourselves an inode cache */
	84	atomic_set(&afs_count_active_inodes, 0);
	85
	86	ret = -ENOMEM;
	87	afs_inode_cachep = kmem_cache_create("afs_inode_cache",
	88	sizeof(struct afs_vnode),
	89	0,
	90	SLAB_HWCACHE_ALIGN,
20c2df83	91	afs_i_init_once);
1da177e4 LT	92	if (!afs_inode_cachep) {
	93	printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n");
	94	return ret;
	95	}
	96
	97	/* now export our filesystem to lesser mortals */
	98	ret = register_filesystem(&afs_fs_type);
	99	if (ret < 0) {
	100	kmem_cache_destroy(afs_inode_cachep);
08e0e7c8	101	_leave(" = %d", ret);
1da177e4 LT	102	return ret;
	103	}
	104
08e0e7c8	105	_leave(" = 0");
1da177e4	106	return 0;
ec26815a	107	}
1da177e4	108
1da177e4 LT	109	/*
	110	* clean up the filesystem
	111	*/
	112	void __exit afs_fs_exit(void)
	113	{
08e0e7c8 DH	114	_enter("");
	115
	116	afs_mntpt_kill_timer();
1da177e4 LT	117	unregister_filesystem(&afs_fs_type);
	118
	119	if (atomic_read(&afs_count_active_inodes) != 0) {
	120	printk("kAFS: %d active inode objects still present\n",
	121	atomic_read(&afs_count_active_inodes));
	122	BUG();
	123	}
	124
	125	kmem_cache_destroy(afs_inode_cachep);
08e0e7c8	126	_leave("");
ec26815a	127	}
1da177e4	128
1da177e4 LT	129	/*
	130	* parse the mount options
	131	* - this function has been shamelessly adapted from the ext3 fs which
	132	* shamelessly adapted it from the msdos fs
	133	*/
00d3b7a4 DH	134	static int afs_parse_options(struct afs_mount_params *params,
00d3b7a4 DH	135	char options, const char *devname)
1da177e4	136	{
08e0e7c8	137	struct afs_cell *cell;
80c72fe4 DH	138	substring_t args[MAX_OPT_ARGS];
	139	char *p;
	140	int token;
1da177e4 LT	141
	142	_enter("%s", options);
	143
	144	options[PAGE_SIZE - 1] = 0;
	145
80c72fe4 DH	146	while ((p = strsep(&options, ","))) {
	147	if (!*p)
	148	continue;
1da177e4	149
80c72fe4 DH	150	token = match_token(p, afs_options_list, args);
	151	switch (token) {
	152	case afs_opt_cell:
	153	cell = afs_cell_lookup(args[0].from,
	154	args[0].to - args[0].from);
08e0e7c8 DH	155	if (IS_ERR(cell))
08e0e7c8 DH	156	return PTR_ERR(cell);
00d3b7a4 DH	157	afs_put_cell(params->cell);
00d3b7a4 DH	158	params->cell = cell;
80c72fe4 DH	159	break;
	160
	161	case afs_opt_rwpath:
	162	params->rwpath = 1;
	163	break;
	164
	165	case afs_opt_vol:
	166	*devname = args[0].from;
	167	break;
	168
	169	default:
	170	printk(KERN_ERR "kAFS:"
	171	" Unknown or invalid mount option: '%s'\n", p);
	172	return -EINVAL;
1da177e4	173	}
1da177e4 LT	174	}
1da177e4 LT	175
80c72fe4 DH	176	_leave(" = 0");
80c72fe4 DH	177	return 0;
ec26815a	178	}
1da177e4	179
00d3b7a4 DH	180	/*
	181	* parse a device name to get cell name, volume name, volume type and R/W
	182	* selector
	183	* - this can be one of the following:
	184	* "%[cell:]volume[.]" R/W volume
	185	* "#[cell:]volume[.]" R/O or R/W volume (rwpath=0),
	186	* or R/W (rwpath=1) volume
	187	* "%[cell:]volume.readonly" R/O volume
	188	* "#[cell:]volume.readonly" R/O volume
	189	* "%[cell:]volume.backup" Backup volume
	190	* "#[cell:]volume.backup" Backup volume
	191	*/
	192	static int afs_parse_device_name(struct afs_mount_params *params,
	193	const char *name)
	194	{
	195	struct afs_cell *cell;
	196	const char cellname, suffix;
	197	int cellnamesz;
	198
	199	_enter(",%s", name);
	200
	201	if (!name) {
	202	printk(KERN_ERR "kAFS: no volume name specified\n");
	203	return -EINVAL;
	204	}
	205
	206	if ((name[0] != '%' && name[0] != '#') \|\| !name[1]) {
	207	printk(KERN_ERR "kAFS: unparsable volume name\n");
	208	return -EINVAL;
	209	}
	210
	211	/* determine the type of volume we're looking for */
	212	params->type = AFSVL_ROVOL;
	213	params->force = false;
	214	if (params->rwpath \|\| name[0] == '%') {
	215	params->type = AFSVL_RWVOL;
	216	params->force = true;
	217	}
	218	name++;
	219
	220	/* split the cell name out if there is one */
	221	params->volname = strchr(name, ':');
	222	if (params->volname) {
	223	cellname = name;
	224	cellnamesz = params->volname - name;
	225	params->volname++;
	226	} else {
	227	params->volname = name;
	228	cellname = NULL;
	229	cellnamesz = 0;
	230	}
	231
	232	/* the volume type is further affected by a possible suffix */
	233	suffix = strrchr(params->volname, '.');
	234	if (suffix) {
	235	if (strcmp(suffix, ".readonly") == 0) {
	236	params->type = AFSVL_ROVOL;
	237	params->force = true;
	238	} else if (strcmp(suffix, ".backup") == 0) {
	239	params->type = AFSVL_BACKVOL;
	240	params->force = true;
	241	} else if (suffix[1] == 0) {
	242	} else {
	243	suffix = NULL;
244	}
245	}
246
247	params->volnamesz = suffix ?
248	suffix - params->volname : strlen(params->volname);
249
250	_debug("cell %.s [%p]",
251	cellnamesz, cellnamesz, cellname ?: "", params->cell);
252
253	/* lookup the cell record */
254	if (cellname \|\| !params->cell) {
255	cell = afs_cell_lookup(cellname, cellnamesz);
256	if (IS_ERR(cell)) {
257	printk(KERN_ERR "kAFS: unable to lookup cell '%s'\n",
258	cellname ?: "");
259	return PTR_ERR(cell);
260	}
261	afs_put_cell(params->cell);
262	params->cell = cell;
263	}
264
265	_debug("CELL:%s [%p] VOLUME:%.s SUFFIX:%s TYPE:%d%s",
266	params->cell->name, params->cell,
267	params->volnamesz, params->volnamesz, params->volname,
268	suffix ?: "-", params->type, params->force ? " FORCE" : "");
269
270	return 0;
271	}
272
1da177e4 LT	273	/*
	274	* check a superblock to see if it's the one we're looking for
	275	*/
	276	static int afs_test_super(struct super_block sb, void data)
	277	{
	278	struct afs_mount_params *params = data;
	279	struct afs_super_info *as = sb->s_fs_info;
	280
	281	return as->volume == params->volume;
ec26815a	282	}
1da177e4	283
1da177e4 LT	284	/*
	285	* fill in the superblock
	286	*/
436058a4	287	static int afs_fill_super(struct super_block sb, void data)
1da177e4 LT	288	{
	289	struct afs_mount_params *params = data;
	290	struct afs_super_info *as = NULL;
	291	struct afs_fid fid;
	292	struct dentry *root = NULL;
	293	struct inode *inode = NULL;
	294	int ret;
	295
08e0e7c8	296	_enter("");
1da177e4 LT	297
1da177e4 LT	298	/* allocate a superblock info record */
b593e48d	299	as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
1da177e4 LT	300	if (!as) {
	301	_leave(" = -ENOMEM");
	302	return -ENOMEM;
	303	}
	304
1da177e4 LT	305	afs_get_volume(params->volume);
	306	as->volume = params->volume;
	307
	308	/* fill in the superblock */
	309	sb->s_blocksize = PAGE_CACHE_SIZE;
	310	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	311	sb->s_magic = AFS_FS_MAGIC;
	312	sb->s_op = &afs_super_ops;
	313	sb->s_fs_info = as;
e1da0222	314	sb->s_bdi = &as->volume->bdi;
1da177e4 LT	315
	316	/* allocate the root inode and dentry */
	317	fid.vid = as->volume->vid;
	318	fid.vnode = 1;
	319	fid.unique = 1;
260a9803	320	inode = afs_iget(sb, params->key, &fid, NULL, NULL);
08e0e7c8 DH	321	if (IS_ERR(inode))
08e0e7c8 DH	322	goto error_inode;
1da177e4 LT	323
	324	ret = -ENOMEM;
	325	root = d_alloc_root(inode);
	326	if (!root)
	327	goto error;
	328
	329	sb->s_root = root;
	330
08e0e7c8	331	_leave(" = 0");
1da177e4 LT	332	return 0;
1da177e4 LT	333
08e0e7c8 DH	334	error_inode:
	335	ret = PTR_ERR(inode);
	336	inode = NULL;
ec26815a	337	error:
1da177e4 LT	338	iput(inode);
	339	afs_put_volume(as->volume);
	340	kfree(as);
	341
	342	sb->s_fs_info = NULL;
	343
08e0e7c8	344	_leave(" = %d", ret);
1da177e4	345	return ret;
ec26815a	346	}
1da177e4	347
1da177e4 LT	348	/*
1da177e4 LT	349	* get an AFS superblock
1da177e4	350	*/
454e2398 DH	351	static int afs_get_sb(struct file_system_type *fs_type,
	352	int flags,
	353	const char *dev_name,
	354	void *options,
	355	struct vfsmount *mnt)
1da177e4 LT	356	{
	357	struct afs_mount_params params;
	358	struct super_block *sb;
08e0e7c8	359	struct afs_volume *vol;
00d3b7a4	360	struct key *key;
969729d5	361	char *new_opts = kstrdup(options, GFP_KERNEL);
1da177e4 LT	362	int ret;
	363
	364	_enter(",,%s,%p", dev_name, options);
	365
	366	memset(&params, 0, sizeof(params));
	367
00d3b7a4	368	/* parse the options and device name */
1da177e4	369	if (options) {
00d3b7a4	370	ret = afs_parse_options(&params, options, &dev_name);
1da177e4 LT	371	if (ret < 0)
1da177e4 LT	372	goto error;
1da177e4 LT	373	}
1da177e4 LT	374
00d3b7a4 DH	375	ret = afs_parse_device_name(&params, dev_name);
	376	if (ret < 0)
	377	goto error;
	378
	379	/* try and do the mount securely */
	380	key = afs_request_key(params.cell);
	381	if (IS_ERR(key)) {
	382	_leave(" = %ld [key]", PTR_ERR(key));
	383	ret = PTR_ERR(key);
	384	goto error;
	385	}
	386	params.key = key;
	387
1da177e4	388	/* parse the device name */
00d3b7a4	389	vol = afs_volume_lookup(&params);
08e0e7c8 DH	390	if (IS_ERR(vol)) {
08e0e7c8 DH	391	ret = PTR_ERR(vol);
1da177e4	392	goto error;
08e0e7c8	393	}
08e0e7c8	394	params.volume = vol;
1da177e4 LT	395
	396	/* allocate a deviceless superblock */
	397	sb = sget(fs_type, afs_test_super, set_anon_super, &params);
08e0e7c8 DH	398	if (IS_ERR(sb)) {
08e0e7c8 DH	399	ret = PTR_ERR(sb);
1da177e4	400	goto error;
08e0e7c8	401	}
1da177e4	402
436058a4 DH	403	if (!sb->s_root) {
	404	/* initial superblock/root creation */
	405	_debug("create");
	406	sb->s_flags = flags;
	407	ret = afs_fill_super(sb, &params);
	408	if (ret < 0) {
6f5bbff9	409	deactivate_locked_super(sb);
436058a4 DH	410	goto error;
436058a4 DH	411	}
2a32cebd	412	save_mount_options(sb, new_opts);
436058a4 DH	413	sb->s_flags \|= MS_ACTIVE;
	414	} else {
	415	_debug("reuse");
	416	ASSERTCMP(sb->s_flags, &, MS_ACTIVE);
1da177e4	417	}
1da177e4	418
436058a4	419	simple_set_mnt(mnt, sb);
1da177e4	420	afs_put_volume(params.volume);
00d3b7a4	421	afs_put_cell(params.cell);
2a32cebd	422	kfree(new_opts);
08e0e7c8	423	_leave(" = 0 [%p]", sb);
454e2398	424	return 0;
1da177e4	425
ec26815a	426	error:
1da177e4	427	afs_put_volume(params.volume);
00d3b7a4 DH	428	afs_put_cell(params.cell);
00d3b7a4 DH	429	key_put(params.key);
969729d5	430	kfree(new_opts);
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
6cfd0148 CH	444	lock_kernel();
6cfd0148 CH	445
1da177e4	446	afs_put_volume(as->volume);
1da177e4	447
6cfd0148 CH	448	unlock_kernel();
6cfd0148 CH	449
1da177e4	450	_leave("");
ec26815a	451	}
1da177e4	452
1da177e4 LT	453	/*
	454	* initialise an inode cache slab element prior to any use
	455	*/
51cc5068	456	static void afs_i_init_once(void *_vnode)
1da177e4	457	{
ec26815a	458	struct afs_vnode *vnode = _vnode;
1da177e4	459
a35afb83 CL	460	memset(vnode, 0, sizeof(*vnode));
	461	inode_init_once(&vnode->vfs_inode);
	462	init_waitqueue_head(&vnode->update_waitq);
	463	mutex_init(&vnode->permits_lock);
	464	mutex_init(&vnode->validate_lock);
	465	spin_lock_init(&vnode->writeback_lock);
	466	spin_lock_init(&vnode->lock);
	467	INIT_LIST_HEAD(&vnode->writebacks);
e8d6c554 DH	468	INIT_LIST_HEAD(&vnode->pending_locks);
	469	INIT_LIST_HEAD(&vnode->granted_locks);
	470	INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);
a35afb83	471	INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
ec26815a	472	}
1da177e4	473
1da177e4 LT	474	/*
	475	* allocate an AFS inode struct from our slab cache
	476	*/
	477	static struct inode afs_alloc_inode(struct super_block sb)
	478	{
	479	struct afs_vnode *vnode;
	480
ec26815a	481	vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
1da177e4 LT	482	if (!vnode)
	483	return NULL;
	484
	485	atomic_inc(&afs_count_active_inodes);
	486
	487	memset(&vnode->fid, 0, sizeof(vnode->fid));
	488	memset(&vnode->status, 0, sizeof(vnode->status));
	489
	490	vnode->volume = NULL;
	491	vnode->update_cnt = 0;
260a9803	492	vnode->flags = 1 << AFS_VNODE_UNSET;
08e0e7c8	493	vnode->cb_promised = false;
1da177e4	494
0f300ca9	495	_leave(" = %p", &vnode->vfs_inode);
1da177e4	496	return &vnode->vfs_inode;
ec26815a	497	}
1da177e4	498
1da177e4 LT	499	/*
	500	* destroy an AFS inode struct
	501	*/
	502	static void afs_destroy_inode(struct inode *inode)
	503	{
08e0e7c8 DH	504	struct afs_vnode *vnode = AFS_FS_I(inode);
08e0e7c8 DH	505
0f300ca9	506	_enter("%p{%x:%u}", inode, vnode->fid.vid, vnode->fid.vnode);
1da177e4	507
08e0e7c8 DH	508	_debug("DESTROY INODE %p", inode);
	509
	510	ASSERTCMP(vnode->server, ==, NULL);
	511
	512	kmem_cache_free(afs_inode_cachep, vnode);
1da177e4	513	atomic_dec(&afs_count_active_inodes);
ec26815a	514	}
45222b9e DH	515
	516	/*
	517	* return information about an AFS volume
	518	*/
	519	static int afs_statfs(struct dentry dentry, struct kstatfs buf)
	520	{
	521	struct afs_volume_status vs;
	522	struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
	523	struct key *key;
	524	int ret;
	525
	526	key = afs_request_key(vnode->volume->cell);
	527	if (IS_ERR(key))
	528	return PTR_ERR(key);
	529
	530	ret = afs_vnode_get_volume_status(vnode, key, &vs);
	531	key_put(key);
	532	if (ret < 0) {
	533	_leave(" = %d", ret);
	534	return ret;
	535	}
	536
	537	buf->f_type = dentry->d_sb->s_magic;
	538	buf->f_bsize = AFS_BLOCK_SIZE;
	539	buf->f_namelen = AFSNAMEMAX - 1;
	540
	541	if (vs.max_quota == 0)
	542	buf->f_blocks = vs.part_max_blocks;
	543	else
	544	buf->f_blocks = vs.max_quota;
	545	buf->f_bavail = buf->f_bfree = buf->f_blocks - vs.blocks_in_use;
	546	return 0;
	547	}