Home Home > GIT Browse > SLE15-AZURE
summaryrefslogtreecommitdiff
blob: 368f7dd21c610e602478603fe1fb5122a2b453b2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
/*
 * 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 void efs_kill_sb(struct super_block *s)
{
	struct efs_sb_info *sbi = SUPER_INFO(s);
	kill_block_super(s);
	kfree(sbi);
}

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

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 = kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	return &ei->vfs_inode;
}

static void efs_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
}

static void efs_destroy_inode(struct inode *inode)
{
	call_rcu(&inode->i_rcu, efs_i_callback);
}

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

static void destroy_inodecache(void)
{
	/*
	 * Make sure all delayed rcu free inodes are flushed before we
	 * destroy cache.
	 */
	rcu_barrier();
	kmem_cache_destroy(efs_inode_cachep);
}

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

static const struct super_operations efs_superblock_operations = {
	.alloc_inode	= efs_alloc_inode,
	.destroy_inode	= efs_destroy_inode,
	.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;
	pr_info(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) {
		pr_warn("SGI disklabel: checksum bad, label corrupted\n");
		return 0;
	}

#ifdef DEBUG
	pr_debug("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]) {
			pr_debug("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)) {
			pr_debug("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) {
		pr_notice("partition table contained no EFS partitions\n");
#ifdef DEBUG
	} else {
		pr_info("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;

 	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)) {
		pr_err("device does not support %d byte blocks\n",
			EFS_BLOCKSIZE);
		return -EINVAL;
	}
  
	/* read the vh (volume header) block */
	bh = sb_bread(s, 0);

	if (!bh) {
		pr_err("cannot read volume header\n");
		return -EIO;
	}

	/*
	 * 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) {
		return -EINVAL;
	}

	bh = sb_bread(s, sb->fs_start + EFS_SUPER);
	if (!bh) {
		pr_err("cannot read superblock\n");
		return -EIO;
	}
		
	if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
#ifdef DEBUG
		pr_warn("invalid superblock at block %u\n",
			sb->fs_start + EFS_SUPER);
#endif
		brelse(bh);
		return -EINVAL;
	}
	brelse(bh);

	if (!(s->s_flags & MS_RDONLY)) {
#ifdef DEBUG
		pr_info("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)) {
		pr_err("get root inode failed\n");
		return PTR_ERR(root);
	}

	s->s_root = d_make_root(root);
	if (!(s->s_root)) {
		pr_err("get root dentry failed\n");
		return -ENOMEM;
	}

	return 0;
}

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;
}