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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};
36MODULE_ALIAS_FS("efs");
37
38static struct pt_types sgi_pt_types[] = {
39 {0x00, "SGI vh"},
40 {0x01, "SGI trkrepl"},
41 {0x02, "SGI secrepl"},
42 {0x03, "SGI raw"},
43 {0x04, "SGI bsd"},
44 {SGI_SYSV, "SGI sysv"},
45 {0x06, "SGI vol"},
46 {SGI_EFS, "SGI efs"},
47 {0x08, "SGI lv"},
48 {0x09, "SGI rlv"},
49 {0x0A, "SGI xfs"},
50 {0x0B, "SGI xfslog"},
51 {0x0C, "SGI xlv"},
52 {0x82, "Linux swap"},
53 {0x83, "Linux native"},
54 {0, NULL}
55};
56
57
58static struct kmem_cache * efs_inode_cachep;
59
60static struct inode *efs_alloc_inode(struct super_block *sb)
61{
62 struct efs_inode_info *ei;
63 ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
64 if (!ei)
65 return NULL;
66 return &ei->vfs_inode;
67}
68
69static void efs_i_callback(struct rcu_head *head)
70{
71 struct inode *inode = container_of(head, struct inode, i_rcu);
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
101
102
103
104 rcu_barrier();
105 kmem_cache_destroy(efs_inode_cachep);
106}
107
108static void efs_put_super(struct super_block *s)
109{
110 kfree(s->s_fs_info);
111 s->s_fs_info = NULL;
112}
113
114static int efs_remount(struct super_block *sb, int *flags, char *data)
115{
116 *flags |= MS_RDONLY;
117 return 0;
118}
119
120static const struct super_operations efs_superblock_operations = {
121 .alloc_inode = efs_alloc_inode,
122 .destroy_inode = efs_destroy_inode,
123 .put_super = efs_put_super,
124 .statfs = efs_statfs,
125 .remount_fs = efs_remount,
126};
127
128static const struct export_operations efs_export_ops = {
129 .fh_to_dentry = efs_fh_to_dentry,
130 .fh_to_parent = efs_fh_to_parent,
131 .get_parent = efs_get_parent,
132};
133
134static int __init init_efs_fs(void) {
135 int err;
136 printk("EFS: "EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
137 err = init_inodecache();
138 if (err)
139 goto out1;
140 err = register_filesystem(&efs_fs_type);
141 if (err)
142 goto out;
143 return 0;
144out:
145 destroy_inodecache();
146out1:
147 return err;
148}
149
150static void __exit exit_efs_fs(void) {
151 unregister_filesystem(&efs_fs_type);
152 destroy_inodecache();
153}
154
155module_init(init_efs_fs)
156module_exit(exit_efs_fs)
157
158static efs_block_t efs_validate_vh(struct volume_header *vh) {
159 int i;
160 __be32 cs, *ui;
161 int csum;
162 efs_block_t sblock = 0;
163 struct pt_types *pt_entry;
164 int pt_type, slice = -1;
165
166 if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
167
168
169
170
171
172 return 0;
173 }
174
175 ui = ((__be32 *) (vh + 1)) - 1;
176 for(csum = 0; ui >= ((__be32 *) vh);) {
177 cs = *ui--;
178 csum += be32_to_cpu(cs);
179 }
180 if (csum) {
181 printk(KERN_INFO "EFS: SGI disklabel: checksum bad, label corrupted\n");
182 return 0;
183 }
184
185#ifdef DEBUG
186 printk(KERN_DEBUG "EFS: bf: \"%16s\"\n", vh->vh_bootfile);
187
188 for(i = 0; i < NVDIR; i++) {
189 int j;
190 char name[VDNAMESIZE+1];
191
192 for(j = 0; j < VDNAMESIZE; j++) {
193 name[j] = vh->vh_vd[i].vd_name[j];
194 }
195 name[j] = (char) 0;
196
197 if (name[0]) {
198 printk(KERN_DEBUG "EFS: vh: %8s block: 0x%08x size: 0x%08x\n",
199 name,
200 (int) be32_to_cpu(vh->vh_vd[i].vd_lbn),
201 (int) be32_to_cpu(vh->vh_vd[i].vd_nbytes));
202 }
203 }
204#endif
205
206 for(i = 0; i < NPARTAB; i++) {
207 pt_type = (int) be32_to_cpu(vh->vh_pt[i].pt_type);
208 for(pt_entry = sgi_pt_types; pt_entry->pt_name; pt_entry++) {
209 if (pt_type == pt_entry->pt_type) break;
210 }
211#ifdef DEBUG
212 if (be32_to_cpu(vh->vh_pt[i].pt_nblks)) {
213 printk(KERN_DEBUG "EFS: pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
214 i,
215 (int) be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
216 (int) be32_to_cpu(vh->vh_pt[i].pt_nblks),
217 pt_type,
218 (pt_entry->pt_name) ? pt_entry->pt_name : "unknown");
219 }
220#endif
221 if (IS_EFS(pt_type)) {
222 sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
223 slice = i;
224 }
225 }
226
227 if (slice == -1) {
228 printk(KERN_NOTICE "EFS: partition table contained no EFS partitions\n");
229#ifdef DEBUG
230 } else {
231 printk(KERN_INFO "EFS: using slice %d (type %s, offset 0x%x)\n",
232 slice,
233 (pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
234 sblock);
235#endif
236 }
237 return sblock;
238}
239
240static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
241
242 if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
243 return -1;
244
245 sb->fs_magic = be32_to_cpu(super->fs_magic);
246 sb->total_blocks = be32_to_cpu(super->fs_size);
247 sb->first_block = be32_to_cpu(super->fs_firstcg);
248 sb->group_size = be32_to_cpu(super->fs_cgfsize);
249 sb->data_free = be32_to_cpu(super->fs_tfree);
250 sb->inode_free = be32_to_cpu(super->fs_tinode);
251 sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
252 sb->total_groups = be16_to_cpu(super->fs_ncg);
253
254 return 0;
255}
256
257static int efs_fill_super(struct super_block *s, void *d, int silent)
258{
259 struct efs_sb_info *sb;
260 struct buffer_head *bh;
261 struct inode *root;
262 int ret = -EINVAL;
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 goto out_no_fs_ul;
274 }
275
276
277 bh = sb_bread(s, 0);
278
279 if (!bh) {
280 printk(KERN_ERR "EFS: cannot read volume header\n");
281 goto out_no_fs_ul;
282 }
283
284
285
286
287
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 goto out_no_fs_ul;
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 goto out_no_fs_ul;
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 goto out_no_fs_ul;
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 ret = PTR_ERR(root);
323 goto out_no_fs;
324 }
325
326 s->s_root = d_make_root(root);
327 if (!(s->s_root)) {
328 printk(KERN_ERR "EFS: get root dentry failed\n");
329 ret = -ENOMEM;
330 goto out_no_fs;
331 }
332
333 return 0;
334
335out_no_fs_ul:
336out_no_fs:
337 s->s_fs_info = NULL;
338 kfree(sb);
339 return ret;
340}
341
342static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
343 struct super_block *sb = dentry->d_sb;
344 struct efs_sb_info *sbi = SUPER_INFO(sb);
345 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
346
347 buf->f_type = EFS_SUPER_MAGIC;
348 buf->f_bsize = EFS_BLOCKSIZE;
349 buf->f_blocks = sbi->total_groups *
350 (sbi->group_size - sbi->inode_blocks);
351 buf->f_bfree = sbi->data_free;
352 buf->f_bavail = sbi->data_free;
353 buf->f_files = sbi->total_groups *
354 sbi->inode_blocks *
355 (EFS_BLOCKSIZE / sizeof(struct efs_dinode));
356 buf->f_ffree = sbi->inode_free;
357 buf->f_fsid.val[0] = (u32)id;
358 buf->f_fsid.val[1] = (u32)(id >> 32);
359 buf->f_namelen = EFS_MAXNAMELEN;
360
361 return 0;
362}
363
364
