blob: c79bc627f1079adf72ac3779befdda1540272dec [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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>
Christoph Hellwiga5694252007-07-17 04:04:28 -070014#include <linux/exportfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/slab.h>
16#include <linux/buffer_head.h>
17#include <linux/vfs.h>
18
David Howells726c3342006-06-23 02:02:58 -070019static int efs_statfs(struct dentry *dentry, struct kstatfs *buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -070020static int efs_fill_super(struct super_block *s, void *d, int silent);
21
David Howells454e2392006-06-23 02:02:57 -070022static int efs_get_sb(struct file_system_type *fs_type,
23 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
Linus Torvalds1da177e2005-04-16 15:20:36 -070024{
David Howells454e2392006-06-23 02:02:57 -070025 return get_sb_bdev(fs_type, flags, dev_name, data, efs_fill_super, mnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -070026}
27
28static struct file_system_type efs_fs_type = {
29 .owner = THIS_MODULE,
30 .name = "efs",
31 .get_sb = efs_get_sb,
32 .kill_sb = kill_block_super,
33 .fs_flags = FS_REQUIRES_DEV,
34};
35
36static struct pt_types sgi_pt_types[] = {
37 {0x00, "SGI vh"},
38 {0x01, "SGI trkrepl"},
39 {0x02, "SGI secrepl"},
40 {0x03, "SGI raw"},
41 {0x04, "SGI bsd"},
42 {SGI_SYSV, "SGI sysv"},
43 {0x06, "SGI vol"},
44 {SGI_EFS, "SGI efs"},
45 {0x08, "SGI lv"},
46 {0x09, "SGI rlv"},
47 {0x0A, "SGI xfs"},
48 {0x0B, "SGI xfslog"},
49 {0x0C, "SGI xlv"},
50 {0x82, "Linux swap"},
51 {0x83, "Linux native"},
52 {0, NULL}
53};
54
55
Christoph Lametere18b8902006-12-06 20:33:20 -080056static struct kmem_cache * efs_inode_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
58static struct inode *efs_alloc_inode(struct super_block *sb)
59{
60 struct efs_inode_info *ei;
Christoph Lametere94b1762006-12-06 20:33:17 -080061 ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 if (!ei)
63 return NULL;
64 return &ei->vfs_inode;
65}
66
67static void efs_destroy_inode(struct inode *inode)
68{
69 kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
70}
71
Christoph Lameter4ba9b9d2007-10-16 23:25:51 -070072static void init_once(struct kmem_cache *cachep, void *foo)
Linus Torvalds1da177e2005-04-16 15:20:36 -070073{
74 struct efs_inode_info *ei = (struct efs_inode_info *) foo;
75
Christoph Lametera35afb82007-05-16 22:10:57 -070076 inode_init_once(&ei->vfs_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -070077}
Paul Mundt20c2df82007-07-20 10:11:58 +090078
Linus Torvalds1da177e2005-04-16 15:20:36 -070079static int init_inodecache(void)
80{
81 efs_inode_cachep = kmem_cache_create("efs_inode_cache",
82 sizeof(struct efs_inode_info),
Paul Jackson4b6a9312006-03-24 03:16:05 -080083 0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
Paul Mundt20c2df82007-07-20 10:11:58 +090084 init_once);
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 if (efs_inode_cachep == NULL)
86 return -ENOMEM;
87 return 0;
88}
89
90static void destroy_inodecache(void)
91{
Alexey Dobriyan1a1d92c2006-09-27 01:49:40 -070092 kmem_cache_destroy(efs_inode_cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -070093}
94
95static void efs_put_super(struct super_block *s)
96{
97 kfree(s->s_fs_info);
98 s->s_fs_info = NULL;
99}
100
101static int efs_remount(struct super_block *sb, int *flags, char *data)
102{
103 *flags |= MS_RDONLY;
104 return 0;
105}
106
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800107static const struct super_operations efs_superblock_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 .alloc_inode = efs_alloc_inode,
109 .destroy_inode = efs_destroy_inode,
110 .read_inode = efs_read_inode,
111 .put_super = efs_put_super,
112 .statfs = efs_statfs,
113 .remount_fs = efs_remount,
114};
115
Christoph Hellwig39655162007-10-21 16:42:17 -0700116static const struct export_operations efs_export_ops = {
Christoph Hellwig05da0802007-10-21 16:42:09 -0700117 .fh_to_dentry = efs_fh_to_dentry,
118 .fh_to_parent = efs_fh_to_parent,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 .get_parent = efs_get_parent,
120};
121
122static 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;
132out:
133 destroy_inodecache();
134out1:
135 return err;
136}
137
138static void __exit exit_efs_fs(void) {
139 unregister_filesystem(&efs_fs_type);
140 destroy_inodecache();
141}
142
143module_init(init_efs_fs)
144module_exit(exit_efs_fs)
145
146static 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 }
Jesper Juhl014c2542006-01-15 02:37:08 +0100225 return sblock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226}
227
228static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
229
Jesper Juhl014c2542006-01-15 02:37:08 +0100230 if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
231 return -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232
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
245static 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;
250
Panagiotis Issarisf8314dc2006-09-27 01:49:37 -0700251 sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 if (!sb)
253 return -ENOMEM;
254 s->s_fs_info = sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255
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
317out_no_fs_ul:
318out_no_fs:
319 s->s_fs_info = NULL;
320 kfree(sb);
321 return -EINVAL;
322}
323
David Howells726c3342006-06-23 02:02:58 -0700324static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
325 struct efs_sb_info *sb = SUPER_INFO(dentry->d_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
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