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

/*
 * super.c
 *
 * Copyright (c) 1999 Al Smith
 *
 * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/exportfs.h>
#include <linux/slab.h>
#include <linux/buffer_head.h>
#include <linux/vfs.h>

#include "efs.h"
#include <linux/efs_vh.h>
#include <linux/efs_fs_sb.h>

static int efs_statfs(struct dentry *dentry, struct kstatfs *buf);
static int efs_fill_super(struct super_block *s, void *d, int silent);

static struct dentry *efs_mount(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data)
{
	return mount_bdev(fs_type, flags, dev_name, data, efs_fill_super);
}

static struct file_system_type efs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "efs",
	.mount		= efs_mount,
	.kill_sb	= kill_block_super,
	.fs_flags	= FS_REQUIRES_DEV,
};

static struct pt_types sgi_pt_types[] = {
	{0x00,		"SGI vh"},
	{0x01,		"SGI trkrepl"},
	{0x02,		"SGI secrepl"},
	{0x03,		"SGI raw"},
	{0x04,		"SGI bsd"},
	{SGI_SYSV,	"SGI sysv"},
	{0x06,		"SGI vol"},
	{SGI_EFS,	"SGI efs"},
	{0x08,		"SGI lv"},
	{0x09,		"SGI rlv"},
	{0x0A,		"SGI xfs"},
	{0x0B,		"SGI xfslog"},
	{0x0C,		"SGI xlv"},
	{0x82,		"Linux swap"},
	{0x83,		"Linux native"},
	{0,		NULL}
};


static struct kmem_cache * efs_inode_cachep;

static struct inode *efs_alloc_inode(struct super_block *sb)
{
	struct efs_inode_info *ei;
	ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	return &ei->vfs_inode;
}

static void efs_destroy_inode(struct inode *inode)
{
	kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
}

static void init_once(void *foo)
{
	struct efs_inode_info *ei = (struct efs_inode_info *) foo;

	inode_init_once(&ei->vfs_inode);
}

static int init_inodecache(void)
{
	efs_inode_cachep = kmem_cache_create("efs_inode_cache",
				sizeof(struct efs_inode_info),
				0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
				init_once);
	if (efs_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	kmem_cache_destroy(efs_inode_cachep);
}

static void efs_put_super(struct super_block *s)
{
	kfree(s->s_fs_info);
	s->s_fs_info = NULL;
}

static int efs_remount(struct super_block *sb, int *flags, char *data)
{
	*flags |= MS_RDONLY;
	return 0;
}

static const struct super_operations efs_superblock_operations = {
	.alloc_inode	= efs_alloc_inode,
	.destroy_inode	= efs_destroy_inode,
	.put_super	= efs_put_super,
	.statfs		= efs_statfs,
	.remount_fs	= efs_remount,
};

static const struct export_operations efs_export_ops = {
	.fh_to_dentry	= efs_fh_to_dentry,
	.fh_to_parent	= efs_fh_to_parent,
	.get_parent	= efs_get_parent,
};

static int __init init_efs_fs(void) {
	int err;
	printk("EFS: "EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
	err = init_inodecache();
	if (err)
		goto out1;
	err = register_filesystem(&efs_fs_type);
	if (err)
		goto out;
	return 0;
out:
	destroy_inodecache();
out1:
	return err;
}

static void __exit exit_efs_fs(void) {
	unregister_filesystem(&efs_fs_type);
	destroy_inodecache();
}

module_init(init_efs_fs)
module_exit(exit_efs_fs)

static efs_block_t efs_validate_vh(struct volume_header *vh) {
	int		i;
	__be32		cs, *ui;
	int		csum;
	efs_block_t	sblock = 0; /* shuts up gcc */
	struct pt_types	*pt_entry;
	int		pt_type, slice = -1;

	if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
		/*
		 * assume that we're dealing with a partition and allow
		 * read_super() to try and detect a valid superblock
		 * on the next block.
		 */
		return 0;
	}

	ui = ((__be32 *) (vh + 1)) - 1;
	for(csum = 0; ui >= ((__be32 *) vh);) {
		cs = *ui--;
		csum += be32_to_cpu(cs);
	}
	if (csum) {
		printk(KERN_INFO "EFS: SGI disklabel: checksum bad, label corrupted\n");
		return 0;
	}

#ifdef DEBUG
	printk(KERN_DEBUG "EFS: bf: \"%16s\"\n", vh->vh_bootfile);

	for(i = 0; i < NVDIR; i++) {
		int	j;
		char	name[VDNAMESIZE+1];

		for(j = 0; j < VDNAMESIZE; j++) {
			name[j] = vh->vh_vd[i].vd_name[j];
		}
		name[j] = (char) 0;

		if (name[0]) {
			printk(KERN_DEBUG "EFS: vh: %8s block: 0x%08x size: 0x%08x\n",
				name,
				(int) be32_to_cpu(vh->vh_vd[i].vd_lbn),
				(int) be32_to_cpu(vh->vh_vd[i].vd_nbytes));
		}
	}
#endif

	for(i = 0; i < NPARTAB; i++) {
		pt_type = (int) be32_to_cpu(vh->vh_pt[i].pt_type);
		for(pt_entry = sgi_pt_types; pt_entry->pt_name; pt_entry++) {
			if (pt_type == pt_entry->pt_type) break;
		}
#ifdef DEBUG
		if (be32_to_cpu(vh->vh_pt[i].pt_nblks)) {
			printk(KERN_DEBUG "EFS: pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
				i,
				(int) be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
				(int) be32_to_cpu(vh->vh_pt[i].pt_nblks),
				pt_type,
				(pt_entry->pt_name) ? pt_entry->pt_name : "unknown");
		}
#endif
		if (IS_EFS(pt_type)) {
			sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
			slice = i;
		}
	}

	if (slice == -1) {
		printk(KERN_NOTICE "EFS: partition table contained no EFS partitions\n");
#ifdef DEBUG
	} else {
		printk(KERN_INFO "EFS: using slice %d (type %s, offset 0x%x)\n",
			slice,
			(pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
			sblock);
#endif
	}
	return sblock;
}

static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {

	if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
		return -1;

	sb->fs_magic     = be32_to_cpu(super->fs_magic);
	sb->total_blocks = be32_to_cpu(super->fs_size);
	sb->first_block  = be32_to_cpu(super->fs_firstcg);
	sb->group_size   = be32_to_cpu(super->fs_cgfsize);
	sb->data_free    = be32_to_cpu(super->fs_tfree);
	sb->inode_free   = be32_to_cpu(super->fs_tinode);
	sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
	sb->total_groups = be16_to_cpu(super->fs_ncg);
    
	return 0;    
}

static int efs_fill_super(struct super_block *s, void *d, int silent)
{
	struct efs_sb_info *sb;
	struct buffer_head *bh;
	struct inode *root;
	int ret = -EINVAL;

 	sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
	if (!sb)
		return -ENOMEM;
	s->s_fs_info = sb;
 
	s->s_magic		= EFS_SUPER_MAGIC;
	if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
		printk(KERN_ERR "EFS: device does not support %d byte blocks\n",
			EFS_BLOCKSIZE);
		goto out_no_fs_ul;
	}
  
	/* read the vh (volume header) block */
	bh = sb_bread(s, 0);

	if (!bh) {
		printk(KERN_ERR "EFS: cannot read volume header\n");
		goto out_no_fs_ul;
	}

	/*
	 * if this returns zero then we didn't find any partition table.
	 * this isn't (yet) an error - just assume for the moment that
	 * the device is valid and go on to search for a superblock.
	 */
	sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
	brelse(bh);

	if (sb->fs_start == -1) {
		goto out_no_fs_ul;
	}

	bh = sb_bread(s, sb->fs_start + EFS_SUPER);
	if (!bh) {
		printk(KERN_ERR "EFS: cannot read superblock\n");
		goto out_no_fs_ul;
	}
		
	if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
#ifdef DEBUG
		printk(KERN_WARNING "EFS: invalid superblock at block %u\n", sb->fs_start + EFS_SUPER);
#endif
		brelse(bh);
		goto out_no_fs_ul;
	}
	brelse(bh);

	if (!(s->s_flags & MS_RDONLY)) {
#ifdef DEBUG
		printk(KERN_INFO "EFS: forcing read-only mode\n");
#endif
		s->s_flags |= MS_RDONLY;
	}
	s->s_op   = &efs_superblock_operations;
	s->s_export_op = &efs_export_ops;
	root = efs_iget(s, EFS_ROOTINODE);
	if (IS_ERR(root)) {
		printk(KERN_ERR "EFS: get root inode failed\n");
		ret = PTR_ERR(root);
		goto out_no_fs;
	}

	s->s_root = d_alloc_root(root);
	if (!(s->s_root)) {
		printk(KERN_ERR "EFS: get root dentry failed\n");
		iput(root);
		ret = -ENOMEM;
		goto out_no_fs;
	}

	return 0;

out_no_fs_ul:
out_no_fs:
	s->s_fs_info = NULL;
	kfree(sb);
	return ret;
}

static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
	struct super_block *sb = dentry->d_sb;
	struct efs_sb_info *sbi = SUPER_INFO(sb);
	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);

	buf->f_type    = EFS_SUPER_MAGIC;	/* efs magic number */
	buf->f_bsize   = EFS_BLOCKSIZE;		/* blocksize */
	buf->f_blocks  = sbi->total_groups *	/* total data blocks */
			(sbi->group_size - sbi->inode_blocks);
	buf->f_bfree   = sbi->data_free;	/* free data blocks */
	buf->f_bavail  = sbi->data_free;	/* free blocks for non-root */
	buf->f_files   = sbi->total_groups *	/* total inodes */
			sbi->inode_blocks *
			(EFS_BLOCKSIZE / sizeof(struct efs_dinode));
	buf->f_ffree   = sbi->inode_free;	/* free inodes */
	buf->f_fsid.val[0] = (u32)id;
	buf->f_fsid.val[1] = (u32)(id >> 32);
	buf->f_namelen = EFS_MAXNAMELEN;	/* max filename length */

	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* super.c
	3	*
	4	* Copyright (c) 1999 Al Smith
	5	*
	6	* Portions derived from work (c) 1995,1996 Christian Vogelgsang.
	7	*/
	8
	9	#include <linux/init.h>
	10	#include <linux/module.h>
a5694255	11	#include <linux/exportfs.h>
1da177e4 LT	12	#include <linux/slab.h>
	13	#include <linux/buffer_head.h>
	14	#include <linux/vfs.h>
	15
45254b4f CH	16	#include "efs.h"
	17	#include <linux/efs_vh.h>
	18	#include <linux/efs_fs_sb.h>
	19
726c3342	20	static int efs_statfs(struct dentry dentry, struct kstatfs buf);
1da177e4 LT	21	static int efs_fill_super(struct super_block s, void d, int silent);
1da177e4 LT	22
152a0836 AV	23	static struct dentry efs_mount(struct file_system_type fs_type,
152a0836 AV	24	int flags, const char dev_name, void data)
1da177e4	25	{
152a0836	26	return mount_bdev(fs_type, flags, dev_name, data, efs_fill_super);
1da177e4 LT	27	}
	28
	29	static struct file_system_type efs_fs_type = {
	30	.owner = THIS_MODULE,
	31	.name = "efs",
152a0836	32	.mount = efs_mount,
1da177e4 LT	33	.kill_sb = kill_block_super,
	34	.fs_flags = FS_REQUIRES_DEV,
	35	};
	36
	37	static struct pt_types sgi_pt_types[] = {
	38	{0x00, "SGI vh"},
	39	{0x01, "SGI trkrepl"},
	40	{0x02, "SGI secrepl"},
	41	{0x03, "SGI raw"},
	42	{0x04, "SGI bsd"},
	43	{SGI_SYSV, "SGI sysv"},
	44	{0x06, "SGI vol"},
	45	{SGI_EFS, "SGI efs"},
	46	{0x08, "SGI lv"},
	47	{0x09, "SGI rlv"},
	48	{0x0A, "SGI xfs"},
	49	{0x0B, "SGI xfslog"},
	50	{0x0C, "SGI xlv"},
	51	{0x82, "Linux swap"},
	52	{0x83, "Linux native"},
	53	{0, NULL}
	54	};
	55
	56
e18b890b	57	static struct kmem_cache * efs_inode_cachep;
1da177e4 LT	58
	59	static struct inode efs_alloc_inode(struct super_block sb)
	60	{
	61	struct efs_inode_info *ei;
e94b1766	62	ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
1da177e4 LT	63	if (!ei)
	64	return NULL;
	65	return &ei->vfs_inode;
	66	}
	67
	68	static void efs_destroy_inode(struct inode *inode)
	69	{
	70	kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
	71	}
	72
51cc5068	73	static void init_once(void *foo)
1da177e4 LT	74	{
	75	struct efs_inode_info ei = (struct efs_inode_info ) foo;
	76
a35afb83	77	inode_init_once(&ei->vfs_inode);
1da177e4	78	}
20c2df83	79
1da177e4 LT	80	static int init_inodecache(void)
	81	{
	82	efs_inode_cachep = kmem_cache_create("efs_inode_cache",
	83	sizeof(struct efs_inode_info),
4b6a9316	84	0, SLAB_RECLAIM_ACCOUNT\|SLAB_MEM_SPREAD,
20c2df83	85	init_once);
1da177e4 LT	86	if (efs_inode_cachep == NULL)
	87	return -ENOMEM;
	88	return 0;
	89	}
	90
	91	static void destroy_inodecache(void)
	92	{
1a1d92c1	93	kmem_cache_destroy(efs_inode_cachep);
1da177e4 LT	94	}
	95
	96	static void efs_put_super(struct super_block *s)
	97	{
	98	kfree(s->s_fs_info);
	99	s->s_fs_info = NULL;
	100	}
	101
	102	static int efs_remount(struct super_block sb, int flags, char *data)
	103	{
	104	*flags \|= MS_RDONLY;
	105	return 0;
	106	}
	107
ee9b6d61	108	static const struct super_operations efs_superblock_operations = {
1da177e4 LT	109	.alloc_inode = efs_alloc_inode,
1da177e4 LT	110	.destroy_inode = efs_destroy_inode,
1da177e4 LT	111	.put_super = efs_put_super,
	112	.statfs = efs_statfs,
	113	.remount_fs = efs_remount,
	114	};
	115
39655164	116	static const struct export_operations efs_export_ops = {
05da0804 CH	117	.fh_to_dentry = efs_fh_to_dentry,
05da0804 CH	118	.fh_to_parent = efs_fh_to_parent,
1da177e4 LT	119	.get_parent = efs_get_parent,
	120	};
	121
	122	static int __init init_efs_fs(void) {
	123	int err;
	124	printk("EFS: "EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
	125	err = init_inodecache();
	126	if (err)
	127	goto out1;
	128	err = register_filesystem(&efs_fs_type);
	129	if (err)
	130	goto out;
	131	return 0;
	132	out:
	133	destroy_inodecache();
	134	out1:
	135	return err;
	136	}
	137
	138	static void __exit exit_efs_fs(void) {
	139	unregister_filesystem(&efs_fs_type);
	140	destroy_inodecache();
	141	}
	142
	143	module_init(init_efs_fs)
	144	module_exit(exit_efs_fs)
	145
	146	static efs_block_t efs_validate_vh(struct volume_header *vh) {
	147	int i;
	148	__be32 cs, *ui;
	149	int csum;
	150	efs_block_t sblock = 0; /* shuts up gcc */
	151	struct pt_types *pt_entry;
	152	int pt_type, slice = -1;
	153
	154	if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
	155	/*
	156	* assume that we're dealing with a partition and allow
	157	* read_super() to try and detect a valid superblock
	158	* on the next block.
	159	*/
	160	return 0;
	161	}
	162
	163	ui = ((__be32 *) (vh + 1)) - 1;
	164	for(csum = 0; ui >= ((__be32 *) vh);) {
	165	cs = *ui--;
	166	csum += be32_to_cpu(cs);
	167	}
	168	if (csum) {
	169	printk(KERN_INFO "EFS: SGI disklabel: checksum bad, label corrupted\n");
	170	return 0;
	171	}
	172
	173	#ifdef DEBUG
	174	printk(KERN_DEBUG "EFS: bf: \"%16s\"\n", vh->vh_bootfile);
	175
	176	for(i = 0; i < NVDIR; i++) {
	177	int j;
	178	char name[VDNAMESIZE+1];
	179
	180	for(j = 0; j < VDNAMESIZE; j++) {
	181	name[j] = vh->vh_vd[i].vd_name[j];
	182	}
183	name[j] = (char) 0;
184
185	if (name[0]) {
186	printk(KERN_DEBUG "EFS: vh: %8s block: 0x%08x size: 0x%08x\n",
187	name,
188	(int) be32_to_cpu(vh->vh_vd[i].vd_lbn),
189	(int) be32_to_cpu(vh->vh_vd[i].vd_nbytes));
190	}
191	}
192	#endif
193
194	for(i = 0; i < NPARTAB; i++) {
195	pt_type = (int) be32_to_cpu(vh->vh_pt[i].pt_type);
196	for(pt_entry = sgi_pt_types; pt_entry->pt_name; pt_entry++) {
197	if (pt_type == pt_entry->pt_type) break;
198	}
199	#ifdef DEBUG
200	if (be32_to_cpu(vh->vh_pt[i].pt_nblks)) {
201	printk(KERN_DEBUG "EFS: pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
202	i,
203	(int) be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
204	(int) be32_to_cpu(vh->vh_pt[i].pt_nblks),
205	pt_type,
206	(pt_entry->pt_name) ? pt_entry->pt_name : "unknown");
207	}
208	#endif
209	if (IS_EFS(pt_type)) {
210	sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
211	slice = i;
212	}
213	}
214
215	if (slice == -1) {
216	printk(KERN_NOTICE "EFS: partition table contained no EFS partitions\n");
217	#ifdef DEBUG
218	} else {
219	printk(KERN_INFO "EFS: using slice %d (type %s, offset 0x%x)\n",
220	slice,
221	(pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
222	sblock);
223	#endif
224	}
014c2544	225	return sblock;
1da177e4 LT	226	}
	227
	228	static int efs_validate_super(struct efs_sb_info sb, struct efs_super super) {
	229
014c2544 JJ	230	if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
014c2544 JJ	231	return -1;
1da177e4 LT	232
	233	sb->fs_magic = be32_to_cpu(super->fs_magic);
	234	sb->total_blocks = be32_to_cpu(super->fs_size);
	235	sb->first_block = be32_to_cpu(super->fs_firstcg);
	236	sb->group_size = be32_to_cpu(super->fs_cgfsize);
	237	sb->data_free = be32_to_cpu(super->fs_tfree);
	238	sb->inode_free = be32_to_cpu(super->fs_tinode);
	239	sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
	240	sb->total_groups = be16_to_cpu(super->fs_ncg);
	241
	242	return 0;
	243	}
	244
	245	static int efs_fill_super(struct super_block s, void d, int silent)
	246	{
	247	struct efs_sb_info *sb;
	248	struct buffer_head *bh;
	249	struct inode *root;
298384cd	250	int ret = -EINVAL;
1da177e4	251
f8314dc6	252	sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
1da177e4 LT	253	if (!sb)
	254	return -ENOMEM;
	255	s->s_fs_info = sb;
1da177e4 LT	256
	257	s->s_magic = EFS_SUPER_MAGIC;
	258	if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
	259	printk(KERN_ERR "EFS: device does not support %d byte blocks\n",
	260	EFS_BLOCKSIZE);
	261	goto out_no_fs_ul;
	262	}
	263
	264	/* read the vh (volume header) block */
	265	bh = sb_bread(s, 0);
	266
	267	if (!bh) {
	268	printk(KERN_ERR "EFS: cannot read volume header\n");
	269	goto out_no_fs_ul;
	270	}
	271
	272	/*
	273	* if this returns zero then we didn't find any partition table.
	274	* this isn't (yet) an error - just assume for the moment that
	275	* the device is valid and go on to search for a superblock.
	276	*/
	277	sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
	278	brelse(bh);
	279
	280	if (sb->fs_start == -1) {
	281	goto out_no_fs_ul;
	282	}
	283
	284	bh = sb_bread(s, sb->fs_start + EFS_SUPER);
	285	if (!bh) {
	286	printk(KERN_ERR "EFS: cannot read superblock\n");
	287	goto out_no_fs_ul;
	288	}
	289
	290	if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
	291	#ifdef DEBUG
	292	printk(KERN_WARNING "EFS: invalid superblock at block %u\n", sb->fs_start + EFS_SUPER);
	293	#endif
	294	brelse(bh);
	295	goto out_no_fs_ul;
	296	}
	297	brelse(bh);
	298
	299	if (!(s->s_flags & MS_RDONLY)) {
	300	#ifdef DEBUG
	301	printk(KERN_INFO "EFS: forcing read-only mode\n");
	302	#endif
	303	s->s_flags \|= MS_RDONLY;
	304	}
	305	s->s_op = &efs_superblock_operations;
	306	s->s_export_op = &efs_export_ops;
298384cd DH	307	root = efs_iget(s, EFS_ROOTINODE);
	308	if (IS_ERR(root)) {
	309	printk(KERN_ERR "EFS: get root inode failed\n");
	310	ret = PTR_ERR(root);
	311	goto out_no_fs;
	312	}
	313
1da177e4	314	s->s_root = d_alloc_root(root);
1da177e4	315	if (!(s->s_root)) {
298384cd	316	printk(KERN_ERR "EFS: get root dentry failed\n");
1da177e4	317	iput(root);
298384cd	318	ret = -ENOMEM;
1da177e4 LT	319	goto out_no_fs;
	320	}
	321
	322	return 0;
	323
	324	out_no_fs_ul:
	325	out_no_fs:
	326	s->s_fs_info = NULL;
	327	kfree(sb);
298384cd	328	return ret;
1da177e4 LT	329	}
1da177e4 LT	330
726c3342	331	static int efs_statfs(struct dentry dentry, struct kstatfs buf) {
514c91a9 CL	332	struct super_block *sb = dentry->d_sb;
	333	struct efs_sb_info *sbi = SUPER_INFO(sb);
	334	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1da177e4 LT	335
	336	buf->f_type = EFS_SUPER_MAGIC; /* efs magic number */
	337	buf->f_bsize = EFS_BLOCKSIZE; /* blocksize */
514c91a9 CL	338	buf->f_blocks = sbi->total_groups * /* total data blocks */
	339	(sbi->group_size - sbi->inode_blocks);
	340	buf->f_bfree = sbi->data_free; /* free data blocks */
	341	buf->f_bavail = sbi->data_free; /* free blocks for non-root */
	342	buf->f_files = sbi->total_groups * /* total inodes */
	343	sbi->inode_blocks *
1da177e4	344	(EFS_BLOCKSIZE / sizeof(struct efs_dinode));
514c91a9 CL	345	buf->f_ffree = sbi->inode_free; /* free inodes */
	346	buf->f_fsid.val[0] = (u32)id;
	347	buf->f_fsid.val[1] = (u32)(id >> 32);
1da177e4 LT	348	buf->f_namelen = EFS_MAXNAMELEN; /* max filename length */
	349
	350	return 0;
	351	}
	352