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  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>
 11#include <linux/exportfs.h>
 12#include <linux/slab.h>
 13#include <linux/buffer_head.h>
 14#include <linux/vfs.h>
 15
 16#include "efs.h"
 17#include <linux/efs_vh.h>
 18#include <linux/efs_fs_sb.h>
 19
 20static int efs_statfs(struct dentry *dentry, struct kstatfs *buf);
 21static int efs_fill_super(struct super_block *s, void *d, int silent);
 22
 23static struct dentry *efs_mount(struct file_system_type *fs_type,
 24	int flags, const char *dev_name, void *data)
 25{
 26	return mount_bdev(fs_type, flags, dev_name, data, efs_fill_super);
 27}
 28
 
 
 
 
 
 
 
 29static struct file_system_type efs_fs_type = {
 30	.owner		= THIS_MODULE,
 31	.name		= "efs",
 32	.mount		= efs_mount,
 33	.kill_sb	= kill_block_super,
 34	.fs_flags	= FS_REQUIRES_DEV,
 35};
 
 36
 37static 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
 57static struct kmem_cache * efs_inode_cachep;
 58
 59static struct inode *efs_alloc_inode(struct super_block *sb)
 60{
 61	struct efs_inode_info *ei;
 62	ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
 63	if (!ei)
 64		return NULL;
 65	return &ei->vfs_inode;
 66}
 67
 68static void efs_i_callback(struct rcu_head *head)
 69{
 70	struct inode *inode = container_of(head, struct inode, i_rcu);
 71	INIT_LIST_HEAD(&inode->i_dentry);
 72	kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
 73}
 74
 75static void efs_destroy_inode(struct inode *inode)
 76{
 77	call_rcu(&inode->i_rcu, efs_i_callback);
 78}
 79
 80static void init_once(void *foo)
 81{
 82	struct efs_inode_info *ei = (struct efs_inode_info *) foo;
 83
 84	inode_init_once(&ei->vfs_inode);
 85}
 86
 87static int init_inodecache(void)
 88{
 89	efs_inode_cachep = kmem_cache_create("efs_inode_cache",
 90				sizeof(struct efs_inode_info),
 91				0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
 92				init_once);
 93	if (efs_inode_cachep == NULL)
 94		return -ENOMEM;
 95	return 0;
 96}
 97
 98static void destroy_inodecache(void)
 99{
 
 
 
 
 
100	kmem_cache_destroy(efs_inode_cachep);
101}
102
103static void efs_put_super(struct super_block *s)
104{
105	kfree(s->s_fs_info);
106	s->s_fs_info = NULL;
107}
108
109static int efs_remount(struct super_block *sb, int *flags, char *data)
110{
 
111	*flags |= MS_RDONLY;
112	return 0;
113}
114
115static const struct super_operations efs_superblock_operations = {
116	.alloc_inode	= efs_alloc_inode,
117	.destroy_inode	= efs_destroy_inode,
118	.put_super	= efs_put_super,
119	.statfs		= efs_statfs,
120	.remount_fs	= efs_remount,
121};
122
123static const struct export_operations efs_export_ops = {
124	.fh_to_dentry	= efs_fh_to_dentry,
125	.fh_to_parent	= efs_fh_to_parent,
126	.get_parent	= efs_get_parent,
127};
128
129static int __init init_efs_fs(void) {
130	int err;
131	printk("EFS: "EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
132	err = init_inodecache();
133	if (err)
134		goto out1;
135	err = register_filesystem(&efs_fs_type);
136	if (err)
137		goto out;
138	return 0;
139out:
140	destroy_inodecache();
141out1:
142	return err;
143}
144
145static void __exit exit_efs_fs(void) {
146	unregister_filesystem(&efs_fs_type);
147	destroy_inodecache();
148}
149
150module_init(init_efs_fs)
151module_exit(exit_efs_fs)
152
153static efs_block_t efs_validate_vh(struct volume_header *vh) {
154	int		i;
155	__be32		cs, *ui;
156	int		csum;
157	efs_block_t	sblock = 0; /* shuts up gcc */
158	struct pt_types	*pt_entry;
159	int		pt_type, slice = -1;
160
161	if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
162		/*
163		 * assume that we're dealing with a partition and allow
164		 * read_super() to try and detect a valid superblock
165		 * on the next block.
166		 */
167		return 0;
168	}
169
170	ui = ((__be32 *) (vh + 1)) - 1;
171	for(csum = 0; ui >= ((__be32 *) vh);) {
172		cs = *ui--;
173		csum += be32_to_cpu(cs);
174	}
175	if (csum) {
176		printk(KERN_INFO "EFS: SGI disklabel: checksum bad, label corrupted\n");
177		return 0;
178	}
179
180#ifdef DEBUG
181	printk(KERN_DEBUG "EFS: bf: \"%16s\"\n", vh->vh_bootfile);
182
183	for(i = 0; i < NVDIR; i++) {
184		int	j;
185		char	name[VDNAMESIZE+1];
186
187		for(j = 0; j < VDNAMESIZE; j++) {
188			name[j] = vh->vh_vd[i].vd_name[j];
189		}
190		name[j] = (char) 0;
191
192		if (name[0]) {
193			printk(KERN_DEBUG "EFS: vh: %8s block: 0x%08x size: 0x%08x\n",
194				name,
195				(int) be32_to_cpu(vh->vh_vd[i].vd_lbn),
196				(int) be32_to_cpu(vh->vh_vd[i].vd_nbytes));
197		}
198	}
199#endif
200
201	for(i = 0; i < NPARTAB; i++) {
202		pt_type = (int) be32_to_cpu(vh->vh_pt[i].pt_type);
203		for(pt_entry = sgi_pt_types; pt_entry->pt_name; pt_entry++) {
204			if (pt_type == pt_entry->pt_type) break;
205		}
206#ifdef DEBUG
207		if (be32_to_cpu(vh->vh_pt[i].pt_nblks)) {
208			printk(KERN_DEBUG "EFS: pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
209				i,
210				(int) be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
211				(int) be32_to_cpu(vh->vh_pt[i].pt_nblks),
212				pt_type,
213				(pt_entry->pt_name) ? pt_entry->pt_name : "unknown");
214		}
215#endif
216		if (IS_EFS(pt_type)) {
217			sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
218			slice = i;
219		}
220	}
221
222	if (slice == -1) {
223		printk(KERN_NOTICE "EFS: partition table contained no EFS partitions\n");
224#ifdef DEBUG
225	} else {
226		printk(KERN_INFO "EFS: using slice %d (type %s, offset 0x%x)\n",
227			slice,
228			(pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
229			sblock);
230#endif
231	}
232	return sblock;
233}
234
235static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
236
237	if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
238		return -1;
239
240	sb->fs_magic     = be32_to_cpu(super->fs_magic);
241	sb->total_blocks = be32_to_cpu(super->fs_size);
242	sb->first_block  = be32_to_cpu(super->fs_firstcg);
243	sb->group_size   = be32_to_cpu(super->fs_cgfsize);
244	sb->data_free    = be32_to_cpu(super->fs_tfree);
245	sb->inode_free   = be32_to_cpu(super->fs_tinode);
246	sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
247	sb->total_groups = be16_to_cpu(super->fs_ncg);
248    
249	return 0;    
250}
251
252static int efs_fill_super(struct super_block *s, void *d, int silent)
253{
254	struct efs_sb_info *sb;
255	struct buffer_head *bh;
256	struct inode *root;
257	int ret = -EINVAL;
258
259 	sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
260	if (!sb)
261		return -ENOMEM;
262	s->s_fs_info = sb;
263 
264	s->s_magic		= EFS_SUPER_MAGIC;
265	if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
266		printk(KERN_ERR "EFS: device does not support %d byte blocks\n",
267			EFS_BLOCKSIZE);
268		goto out_no_fs_ul;
269	}
270  
271	/* read the vh (volume header) block */
272	bh = sb_bread(s, 0);
273
274	if (!bh) {
275		printk(KERN_ERR "EFS: cannot read volume header\n");
276		goto out_no_fs_ul;
277	}
278
279	/*
280	 * if this returns zero then we didn't find any partition table.
281	 * this isn't (yet) an error - just assume for the moment that
282	 * the device is valid and go on to search for a superblock.
283	 */
284	sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
285	brelse(bh);
286
287	if (sb->fs_start == -1) {
288		goto out_no_fs_ul;
289	}
290
291	bh = sb_bread(s, sb->fs_start + EFS_SUPER);
292	if (!bh) {
293		printk(KERN_ERR "EFS: cannot read superblock\n");
294		goto out_no_fs_ul;
295	}
296		
297	if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
298#ifdef DEBUG
299		printk(KERN_WARNING "EFS: invalid superblock at block %u\n", sb->fs_start + EFS_SUPER);
300#endif
301		brelse(bh);
302		goto out_no_fs_ul;
303	}
304	brelse(bh);
305
306	if (!(s->s_flags & MS_RDONLY)) {
307#ifdef DEBUG
308		printk(KERN_INFO "EFS: forcing read-only mode\n");
309#endif
310		s->s_flags |= MS_RDONLY;
311	}
312	s->s_op   = &efs_superblock_operations;
313	s->s_export_op = &efs_export_ops;
314	root = efs_iget(s, EFS_ROOTINODE);
315	if (IS_ERR(root)) {
316		printk(KERN_ERR "EFS: get root inode failed\n");
317		ret = PTR_ERR(root);
318		goto out_no_fs;
319	}
320
321	s->s_root = d_alloc_root(root);
322	if (!(s->s_root)) {
323		printk(KERN_ERR "EFS: get root dentry failed\n");
324		iput(root);
325		ret = -ENOMEM;
326		goto out_no_fs;
327	}
328
329	return 0;
330
331out_no_fs_ul:
332out_no_fs:
333	s->s_fs_info = NULL;
334	kfree(sb);
335	return ret;
336}
337
338static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
339	struct super_block *sb = dentry->d_sb;
340	struct efs_sb_info *sbi = SUPER_INFO(sb);
341	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
342
343	buf->f_type    = EFS_SUPER_MAGIC;	/* efs magic number */
344	buf->f_bsize   = EFS_BLOCKSIZE;		/* blocksize */
345	buf->f_blocks  = sbi->total_groups *	/* total data blocks */
346			(sbi->group_size - sbi->inode_blocks);
347	buf->f_bfree   = sbi->data_free;	/* free data blocks */
348	buf->f_bavail  = sbi->data_free;	/* free blocks for non-root */
349	buf->f_files   = sbi->total_groups *	/* total inodes */
350			sbi->inode_blocks *
351			(EFS_BLOCKSIZE / sizeof(struct efs_dinode));
352	buf->f_ffree   = sbi->inode_free;	/* free inodes */
353	buf->f_fsid.val[0] = (u32)id;
354	buf->f_fsid.val[1] = (u32)(id >> 32);
355	buf->f_namelen = EFS_MAXNAMELEN;	/* max filename length */
356
357	return 0;
358}
359
  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>
 11#include <linux/exportfs.h>
 12#include <linux/slab.h>
 13#include <linux/buffer_head.h>
 14#include <linux/vfs.h>
 15
 16#include "efs.h"
 17#include <linux/efs_vh.h>
 18#include <linux/efs_fs_sb.h>
 19
 20static int efs_statfs(struct dentry *dentry, struct kstatfs *buf);
 21static int efs_fill_super(struct super_block *s, void *d, int silent);
 22
 23static struct dentry *efs_mount(struct file_system_type *fs_type,
 24	int flags, const char *dev_name, void *data)
 25{
 26	return mount_bdev(fs_type, flags, dev_name, data, efs_fill_super);
 27}
 28
 29static void efs_kill_sb(struct super_block *s)
 30{
 31	struct efs_sb_info *sbi = SUPER_INFO(s);
 32	kill_block_super(s);
 33	kfree(sbi);
 34}
 35
 36static struct file_system_type efs_fs_type = {
 37	.owner		= THIS_MODULE,
 38	.name		= "efs",
 39	.mount		= efs_mount,
 40	.kill_sb	= efs_kill_sb,
 41	.fs_flags	= FS_REQUIRES_DEV,
 42};
 43MODULE_ALIAS_FS("efs");
 44
 45static struct pt_types sgi_pt_types[] = {
 46	{0x00,		"SGI vh"},
 47	{0x01,		"SGI trkrepl"},
 48	{0x02,		"SGI secrepl"},
 49	{0x03,		"SGI raw"},
 50	{0x04,		"SGI bsd"},
 51	{SGI_SYSV,	"SGI sysv"},
 52	{0x06,		"SGI vol"},
 53	{SGI_EFS,	"SGI efs"},
 54	{0x08,		"SGI lv"},
 55	{0x09,		"SGI rlv"},
 56	{0x0A,		"SGI xfs"},
 57	{0x0B,		"SGI xfslog"},
 58	{0x0C,		"SGI xlv"},
 59	{0x82,		"Linux swap"},
 60	{0x83,		"Linux native"},
 61	{0,		NULL}
 62};
 63
 64
 65static struct kmem_cache * efs_inode_cachep;
 66
 67static struct inode *efs_alloc_inode(struct super_block *sb)
 68{
 69	struct efs_inode_info *ei;
 70	ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
 71	if (!ei)
 72		return NULL;
 73	return &ei->vfs_inode;
 74}
 75
 76static void efs_i_callback(struct rcu_head *head)
 77{
 78	struct inode *inode = container_of(head, struct inode, i_rcu);
 
 79	kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
 80}
 81
 82static void efs_destroy_inode(struct inode *inode)
 83{
 84	call_rcu(&inode->i_rcu, efs_i_callback);
 85}
 86
 87static void init_once(void *foo)
 88{
 89	struct efs_inode_info *ei = (struct efs_inode_info *) foo;
 90
 91	inode_init_once(&ei->vfs_inode);
 92}
 93
 94static int __init init_inodecache(void)
 95{
 96	efs_inode_cachep = kmem_cache_create("efs_inode_cache",
 97				sizeof(struct efs_inode_info),
 98				0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
 99				init_once);
100	if (efs_inode_cachep == NULL)
101		return -ENOMEM;
102	return 0;
103}
104
105static void destroy_inodecache(void)
106{
107	/*
108	 * Make sure all delayed rcu free inodes are flushed before we
109	 * destroy cache.
110	 */
111	rcu_barrier();
112	kmem_cache_destroy(efs_inode_cachep);
113}
114
 
 
 
 
 
 
115static int efs_remount(struct super_block *sb, int *flags, char *data)
116{
117	sync_filesystem(sb);
118	*flags |= MS_RDONLY;
119	return 0;
120}
121
122static const struct super_operations efs_superblock_operations = {
123	.alloc_inode	= efs_alloc_inode,
124	.destroy_inode	= efs_destroy_inode,
 
125	.statfs		= efs_statfs,
126	.remount_fs	= efs_remount,
127};
128
129static const struct export_operations efs_export_ops = {
130	.fh_to_dentry	= efs_fh_to_dentry,
131	.fh_to_parent	= efs_fh_to_parent,
132	.get_parent	= efs_get_parent,
133};
134
135static int __init init_efs_fs(void) {
136	int err;
137	printk("EFS: "EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
138	err = init_inodecache();
139	if (err)
140		goto out1;
141	err = register_filesystem(&efs_fs_type);
142	if (err)
143		goto out;
144	return 0;
145out:
146	destroy_inodecache();
147out1:
148	return err;
149}
150
151static void __exit exit_efs_fs(void) {
152	unregister_filesystem(&efs_fs_type);
153	destroy_inodecache();
154}
155
156module_init(init_efs_fs)
157module_exit(exit_efs_fs)
158
159static efs_block_t efs_validate_vh(struct volume_header *vh) {
160	int		i;
161	__be32		cs, *ui;
162	int		csum;
163	efs_block_t	sblock = 0; /* shuts up gcc */
164	struct pt_types	*pt_entry;
165	int		pt_type, slice = -1;
166
167	if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
168		/*
169		 * assume that we're dealing with a partition and allow
170		 * read_super() to try and detect a valid superblock
171		 * on the next block.
172		 */
173		return 0;
174	}
175
176	ui = ((__be32 *) (vh + 1)) - 1;
177	for(csum = 0; ui >= ((__be32 *) vh);) {
178		cs = *ui--;
179		csum += be32_to_cpu(cs);
180	}
181	if (csum) {
182		printk(KERN_INFO "EFS: SGI disklabel: checksum bad, label corrupted\n");
183		return 0;
184	}
185
186#ifdef DEBUG
187	printk(KERN_DEBUG "EFS: bf: \"%16s\"\n", vh->vh_bootfile);
188
189	for(i = 0; i < NVDIR; i++) {
190		int	j;
191		char	name[VDNAMESIZE+1];
192
193		for(j = 0; j < VDNAMESIZE; j++) {
194			name[j] = vh->vh_vd[i].vd_name[j];
195		}
196		name[j] = (char) 0;
197
198		if (name[0]) {
199			printk(KERN_DEBUG "EFS: vh: %8s block: 0x%08x size: 0x%08x\n",
200				name,
201				(int) be32_to_cpu(vh->vh_vd[i].vd_lbn),
202				(int) be32_to_cpu(vh->vh_vd[i].vd_nbytes));
203		}
204	}
205#endif
206
207	for(i = 0; i < NPARTAB; i++) {
208		pt_type = (int) be32_to_cpu(vh->vh_pt[i].pt_type);
209		for(pt_entry = sgi_pt_types; pt_entry->pt_name; pt_entry++) {
210			if (pt_type == pt_entry->pt_type) break;
211		}
212#ifdef DEBUG
213		if (be32_to_cpu(vh->vh_pt[i].pt_nblks)) {
214			printk(KERN_DEBUG "EFS: pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
215				i,
216				(int) be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
217				(int) be32_to_cpu(vh->vh_pt[i].pt_nblks),
218				pt_type,
219				(pt_entry->pt_name) ? pt_entry->pt_name : "unknown");
220		}
221#endif
222		if (IS_EFS(pt_type)) {
223			sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
224			slice = i;
225		}
226	}
227
228	if (slice == -1) {
229		printk(KERN_NOTICE "EFS: partition table contained no EFS partitions\n");
230#ifdef DEBUG
231	} else {
232		printk(KERN_INFO "EFS: using slice %d (type %s, offset 0x%x)\n",
233			slice,
234			(pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
235			sblock);
236#endif
237	}
238	return sblock;
239}
240
241static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
242
243	if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
244		return -1;
245
246	sb->fs_magic     = be32_to_cpu(super->fs_magic);
247	sb->total_blocks = be32_to_cpu(super->fs_size);
248	sb->first_block  = be32_to_cpu(super->fs_firstcg);
249	sb->group_size   = be32_to_cpu(super->fs_cgfsize);
250	sb->data_free    = be32_to_cpu(super->fs_tfree);
251	sb->inode_free   = be32_to_cpu(super->fs_tinode);
252	sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
253	sb->total_groups = be16_to_cpu(super->fs_ncg);
254    
255	return 0;    
256}
257
258static int efs_fill_super(struct super_block *s, void *d, int silent)
259{
260	struct efs_sb_info *sb;
261	struct buffer_head *bh;
262	struct inode *root;
 
263
264 	sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
265	if (!sb)
266		return -ENOMEM;
267	s->s_fs_info = sb;
268 
269	s->s_magic		= EFS_SUPER_MAGIC;
270	if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
271		printk(KERN_ERR "EFS: device does not support %d byte blocks\n",
272			EFS_BLOCKSIZE);
273		return -EINVAL;
274	}
275  
276	/* read the vh (volume header) block */
277	bh = sb_bread(s, 0);
278
279	if (!bh) {
280		printk(KERN_ERR "EFS: cannot read volume header\n");
281		return -EINVAL;
282	}
283
284	/*
285	 * if this returns zero then we didn't find any partition table.
286	 * this isn't (yet) an error - just assume for the moment that
287	 * the device is valid and go on to search for a superblock.
288	 */
289	sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
290	brelse(bh);
291
292	if (sb->fs_start == -1) {
293		return -EINVAL;
294	}
295
296	bh = sb_bread(s, sb->fs_start + EFS_SUPER);
297	if (!bh) {
298		printk(KERN_ERR "EFS: cannot read superblock\n");
299		return -EINVAL;
300	}
301		
302	if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
303#ifdef DEBUG
304		printk(KERN_WARNING "EFS: invalid superblock at block %u\n", sb->fs_start + EFS_SUPER);
305#endif
306		brelse(bh);
307		return -EINVAL;
308	}
309	brelse(bh);
310
311	if (!(s->s_flags & MS_RDONLY)) {
312#ifdef DEBUG
313		printk(KERN_INFO "EFS: forcing read-only mode\n");
314#endif
315		s->s_flags |= MS_RDONLY;
316	}
317	s->s_op   = &efs_superblock_operations;
318	s->s_export_op = &efs_export_ops;
319	root = efs_iget(s, EFS_ROOTINODE);
320	if (IS_ERR(root)) {
321		printk(KERN_ERR "EFS: get root inode failed\n");
322		return PTR_ERR(root);
 
323	}
324
325	s->s_root = d_make_root(root);
326	if (!(s->s_root)) {
327		printk(KERN_ERR "EFS: get root dentry failed\n");
328		return -ENOMEM;
 
 
329	}
330
331	return 0;
 
 
 
 
 
 
332}
333
334static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
335	struct super_block *sb = dentry->d_sb;
336	struct efs_sb_info *sbi = SUPER_INFO(sb);
337	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
338
339	buf->f_type    = EFS_SUPER_MAGIC;	/* efs magic number */
340	buf->f_bsize   = EFS_BLOCKSIZE;		/* blocksize */
341	buf->f_blocks  = sbi->total_groups *	/* total data blocks */
342			(sbi->group_size - sbi->inode_blocks);
343	buf->f_bfree   = sbi->data_free;	/* free data blocks */
344	buf->f_bavail  = sbi->data_free;	/* free blocks for non-root */
345	buf->f_files   = sbi->total_groups *	/* total inodes */
346			sbi->inode_blocks *
347			(EFS_BLOCKSIZE / sizeof(struct efs_dinode));
348	buf->f_ffree   = sbi->inode_free;	/* free inodes */
349	buf->f_fsid.val[0] = (u32)id;
350	buf->f_fsid.val[1] = (u32)(id >> 32);
351	buf->f_namelen = EFS_MAXNAMELEN;	/* max filename length */
352
353	return 0;
354}
355