[linux.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/efs_fs.h>
#include <linux/efs_vh.h>
#include <linux/efs_fs_sb.h>
#include <linux/slab.h>
#include <linux/buffer_head.h>
#include <linux/vfs.h>

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

static struct super_block *efs_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data)
{
	return get_sb_bdev(fs_type, flags, dev_name, data, efs_fill_super);
}

static struct file_system_type efs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "efs",
	.get_sb		= efs_get_sb,
	.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 kmem_cache_t * 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, SLAB_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, kmem_cache_t * cachep, unsigned long flags)
{
	struct efs_inode_info *ei = (struct efs_inode_info *) foo;

	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
	    SLAB_CTOR_CONSTRUCTOR)
		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,
				init_once, NULL);
	if (efs_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	if (kmem_cache_destroy(efs_inode_cachep))
		printk(KERN_INFO "efs_inode_cache: not all structures were freed\n");
}

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

static struct export_operations efs_export_ops = {
	.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;

 	sb = kmalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
	if (!sb)
		return -ENOMEM;
	s->s_fs_info = sb;
	memset(sb, 0, sizeof(struct efs_sb_info));
 
	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 = iget(s, EFS_ROOTINODE);
	s->s_root = d_alloc_root(root);
 
	if (!(s->s_root)) {
		printk(KERN_ERR "EFS: get root inode failed\n");
		iput(root);
		goto out_no_fs;
	}

	return 0;

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

static int efs_statfs(struct super_block *s, struct kstatfs *buf) {
	struct efs_sb_info *sb = SUPER_INFO(s);

	buf->f_type    = EFS_SUPER_MAGIC;	/* efs magic number */
	buf->f_bsize   = EFS_BLOCKSIZE;		/* blocksize */
	buf->f_blocks  = sb->total_groups *	/* total data blocks */
			(sb->group_size - sb->inode_blocks);
	buf->f_bfree   = sb->data_free;		/* free data blocks */
	buf->f_bavail  = sb->data_free;		/* free blocks for non-root */
	buf->f_files   = sb->total_groups *	/* total inodes */
			sb->inode_blocks *
			(EFS_BLOCKSIZE / sizeof(struct efs_dinode));
	buf->f_ffree   = sb->inode_free;	/* free inodes */
	buf->f_fsid.val[0] = (sb->fs_magic >> 16) & 0xffff; /* fs ID */
	buf->f_fsid.val[1] =  sb->fs_magic        & 0xffff; /* fs ID */
	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>
	11	#include <linux/efs_fs.h>
	12	#include <linux/efs_vh.h>
	13	#include <linux/efs_fs_sb.h>
	14	#include <linux/slab.h>
	15	#include <linux/buffer_head.h>
	16	#include <linux/vfs.h>
	17
	18	static int efs_statfs(struct super_block s, struct kstatfs buf);
	19	static int efs_fill_super(struct super_block s, void d, int silent);
	20
	21	static struct super_block efs_get_sb(struct file_system_type fs_type,
	22	int flags, const char dev_name, void data)
	23	{
	24	return get_sb_bdev(fs_type, flags, dev_name, data, efs_fill_super);
	25	}
	26
	27	static struct file_system_type efs_fs_type = {
	28	.owner = THIS_MODULE,
	29	.name = "efs",
	30	.get_sb = efs_get_sb,
	31	.kill_sb = kill_block_super,
	32	.fs_flags = FS_REQUIRES_DEV,
	33	};
	34
	35	static struct pt_types sgi_pt_types[] = {
	36	{0x00, "SGI vh"},
	37	{0x01, "SGI trkrepl"},
	38	{0x02, "SGI secrepl"},
	39	{0x03, "SGI raw"},
	40	{0x04, "SGI bsd"},
	41	{SGI_SYSV, "SGI sysv"},
	42	{0x06, "SGI vol"},
	43	{SGI_EFS, "SGI efs"},
	44	{0x08, "SGI lv"},
	45	{0x09, "SGI rlv"},
	46	{0x0A, "SGI xfs"},
	47	{0x0B, "SGI xfslog"},
	48	{0x0C, "SGI xlv"},
	49	{0x82, "Linux swap"},
	50	{0x83, "Linux native"},
	51	{0, NULL}
	52	};
	53
	54
	55	static kmem_cache_t * efs_inode_cachep;
	56
	57	static struct inode efs_alloc_inode(struct super_block sb)
	58	{
	59	struct efs_inode_info *ei;
	60	ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, SLAB_KERNEL);
	61	if (!ei)
	62	return NULL;
	63	return &ei->vfs_inode;
	64	}
65
66	static void efs_destroy_inode(struct inode *inode)
67	{
68	kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
69	}
70
71	static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
72	{
73	struct efs_inode_info ei = (struct efs_inode_info ) foo;
74
75	if ((flags & (SLAB_CTOR_VERIFY\|SLAB_CTOR_CONSTRUCTOR)) ==
76	SLAB_CTOR_CONSTRUCTOR)
77	inode_init_once(&ei->vfs_inode);
78	}
79
80	static int init_inodecache(void)
81	{
82	efs_inode_cachep = kmem_cache_create("efs_inode_cache",
83	sizeof(struct efs_inode_info),
84	0, SLAB_RECLAIM_ACCOUNT,
85	init_once, NULL);
86	if (efs_inode_cachep == NULL)
87	return -ENOMEM;
88	return 0;
89	}
90
91	static void destroy_inodecache(void)
92	{
93	if (kmem_cache_destroy(efs_inode_cachep))
94	printk(KERN_INFO "efs_inode_cache: not all structures were freed\n");
95	}
96
97	static void efs_put_super(struct super_block *s)
98	{
99	kfree(s->s_fs_info);
100	s->s_fs_info = NULL;
101	}
102
103	static int efs_remount(struct super_block sb, int flags, char *data)
104	{
105	*flags \|= MS_RDONLY;
106	return 0;
107	}
108
109	static struct super_operations efs_superblock_operations = {
110	.alloc_inode = efs_alloc_inode,
111	.destroy_inode = efs_destroy_inode,
112	.read_inode = efs_read_inode,
113	.put_super = efs_put_super,
114	.statfs = efs_statfs,
115	.remount_fs = efs_remount,
116	};
117
118	static struct export_operations efs_export_ops = {
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	}
225	return(sblock);
226	}
227
228	static int efs_validate_super(struct efs_sb_info sb, struct efs_super super) {
229
230	if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic))) return -1;
231
232	sb->fs_magic = be32_to_cpu(super->fs_magic);
233	sb->total_blocks = be32_to_cpu(super->fs_size);
234	sb->first_block = be32_to_cpu(super->fs_firstcg);
235	sb->group_size = be32_to_cpu(super->fs_cgfsize);
236	sb->data_free = be32_to_cpu(super->fs_tfree);
237	sb->inode_free = be32_to_cpu(super->fs_tinode);
238	sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
239	sb->total_groups = be16_to_cpu(super->fs_ncg);
240
241	return 0;
242	}
243
244	static int efs_fill_super(struct super_block s, void d, int silent)
245	{
246	struct efs_sb_info *sb;
247	struct buffer_head *bh;
248	struct inode *root;
249
250	sb = kmalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
251	if (!sb)
252	return -ENOMEM;
253	s->s_fs_info = sb;
254	memset(sb, 0, sizeof(struct efs_sb_info));
255
256	s->s_magic = EFS_SUPER_MAGIC;
257	if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
258	printk(KERN_ERR "EFS: device does not support %d byte blocks\n",
259	EFS_BLOCKSIZE);
260	goto out_no_fs_ul;
261	}
262
263	/* read the vh (volume header) block */
264	bh = sb_bread(s, 0);
265
266	if (!bh) {
267	printk(KERN_ERR "EFS: cannot read volume header\n");
268	goto out_no_fs_ul;
269	}
270
271	/*
272	* if this returns zero then we didn't find any partition table.
273	* this isn't (yet) an error - just assume for the moment that
274	* the device is valid and go on to search for a superblock.
275	*/
276	sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
277	brelse(bh);
278
279	if (sb->fs_start == -1) {
280	goto out_no_fs_ul;
281	}
282
283	bh = sb_bread(s, sb->fs_start + EFS_SUPER);
284	if (!bh) {
285	printk(KERN_ERR "EFS: cannot read superblock\n");
286	goto out_no_fs_ul;
287	}
288
289	if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
290	#ifdef DEBUG
291	printk(KERN_WARNING "EFS: invalid superblock at block %u\n", sb->fs_start + EFS_SUPER);
292	#endif
293	brelse(bh);
294	goto out_no_fs_ul;
295	}
296	brelse(bh);
297
298	if (!(s->s_flags & MS_RDONLY)) {
299	#ifdef DEBUG
300	printk(KERN_INFO "EFS: forcing read-only mode\n");
301	#endif
302	s->s_flags \|= MS_RDONLY;
303	}
304	s->s_op = &efs_superblock_operations;
305	s->s_export_op = &efs_export_ops;
306	root = iget(s, EFS_ROOTINODE);
307	s->s_root = d_alloc_root(root);
308
309	if (!(s->s_root)) {
310	printk(KERN_ERR "EFS: get root inode failed\n");
311	iput(root);
312	goto out_no_fs;
313	}
314
315	return 0;
316
317	out_no_fs_ul:
318	out_no_fs:
319	s->s_fs_info = NULL;
320	kfree(sb);
321	return -EINVAL;
322	}
323
324	static int efs_statfs(struct super_block s, struct kstatfs buf) {
325	struct efs_sb_info *sb = SUPER_INFO(s);
326
327	buf->f_type = EFS_SUPER_MAGIC; /* efs magic number */
328	buf->f_bsize = EFS_BLOCKSIZE; /* blocksize */
329	buf->f_blocks = sb->total_groups * /* total data blocks */
330	(sb->group_size - sb->inode_blocks);
331	buf->f_bfree = sb->data_free; /* free data blocks */
332	buf->f_bavail = sb->data_free; /* free blocks for non-root */
333	buf->f_files = sb->total_groups * /* total inodes */
334	sb->inode_blocks *
335	(EFS_BLOCKSIZE / sizeof(struct efs_dinode));
336	buf->f_ffree = sb->inode_free; /* free inodes */
337	buf->f_fsid.val[0] = (sb->fs_magic >> 16) & 0xffff; /* fs ID */
338	buf->f_fsid.val[1] = sb->fs_magic & 0xffff; /* fs ID */
339	buf->f_namelen = EFS_MAXNAMELEN; /* max filename length */
340
341	return 0;
342	}
343