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